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Student
Abstracts at ORNL:
A Case Study of Efficient Social Network Simulation through General Processing
on Graphics Processing Units. BRANDON
AABY (Maryville College, Maryville, TN, 37777) KALYAN S. PERUMALLA
PH.D (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Agent based simulation has
been both a large area of study and a widely used tool for scientific research
in past
years. Current implementations run on standard CPUs, and with the requirement
of processing ever growing data sets, higher computational speed is of the utmost
importance. General processing on graphics processing units (GPGPU) is an emerging
platform offering the possibility of increased speed for data sets and models
that can be processed in parallel. Agent based simulation is one such candidate
for performance gains in a GPGPU implementation. My research has focused on thoroughly
investigating GPGPU’s suitability for providing researchers with a more efficient
way of conducting agent based simulation research. Studies were done using two
conventional models: two-dimensional diffusion and Conway’s Game of Life. I first
created an optimized CPU diffusion model and, following a determination of accuracy,
compared computational speed with an Open Graphics Library GPGPU implementation
previously developed at Oak Ridge National Laboratory. Similarly, like studies
were completed with the Game of Life. Following this strict CPU and GPGPU comparison,
further comparisons and analyses were conducted with a widely used agent based
simulation API, Repast. Evaluations involving Repast revolved around the premise
that were GPGPU to be harnessed by researchers for agent based simulation, it
must be competitive with currently used research technologies. Results obtained
with both two-dimensional diffusion and the Game of Life show significant performance
gains through GPGPU. For a plethora of data sizes, it has been found that the
GPU processes the models in parallel at much greater rates than both optimized
CPU code and Repast. Furthermore, as both sample size and the number of iterations
through the model increase, the gap between GPU and CPU performance becomes even
wider. These successful studies are to now be extended by investigating new models
through GPGPU and exploring compatibility with necessary agent based simulation
functions, such as image generation. Nonetheless, this research has certainly
shown that GPGPU has the potential to become an efficient and viable tool for
researchers.
A Case Study of the Performance of Speculative Asynchronous Simulation on Parallel
Computers. PATRICK WILKERSON (Austin Peay State University, Clarksville,
TN, 37044) KALYAN PERUMALLA (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Modern supercomputers use
thousands of processors running in parallel to achieve their high computational
speeds.
However, on such large processor counts, communication and synchronization operations
can waste valuable processor time. Communication involves processors exchanging
intermediate computed data that needs to be shared by processors at runtime.
Synchronization involves processors ensuring the mutual orderings of operations
across processors are correct. In this work, we investigated the runtime efficiency
of two methods that are aimed at reducing communication and synchronization costs,
respectively, namely, asynchronous updates and speculative execution. The experimental
investigation is performed on a parallel finite difference time domain (FDTD)
simulation developed at ORNL, which has wide applicability in simulating various
physical system phenomena. It uses an iterative algorithm to reduce communication
by allowing messages to be asynchronously sent when the change in values on a
given processor is greater than some threshold value. We conducted research to
develop an empirical performance study of the algorithm. The first part of asynchronous
updates is accomplished by exploring the effect of threshold-based communication
on overall runtime of the parallel simulation, with the number of processors
increasing. A significant improvement in performance on up to 64 processors was
observed when using the asynchronous update scheme, due to reduced communication.
We are currently working on the synchronization aspect of the problem, to relieve
the tight coupling among processors, using "speculative
execution" with sophisticated "rollback" techniques being developed
in an ORNL Laboratory Directed Research and Development (LDRD) project. In speculative
execution, processors are allowed to progress without having to wait for other
processors, but any violations in ordering of computations are detected and corrected
using rollback techniques. Further research is being done to implement a rollback
mechanism necessary for optimized parallel execution. Preliminary results on
a special case of the synchronization mechanism show improved speedup over and
above the gains of asynchronous updates on up to 64 processors. We are working
towards implementing the more general rollback method and expect to complete
the performance study on the generalized asynchronous speculative execution.
A Computational Model for Analyzing the Biochemical Pathways of Matrix Metalloproteinase
(MMP) 2&9 in Collagen Type IV Proteolysis. ELIZABETH
O'QUINN O'QUINN (Wofford College, Spartanburg, SC, 29369) KARA KRUSE
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Cardiovascular disease
is the leading cause of death in first world countries. The imbalance of matrix
degrading enzymes and structural proteins within the extracellular matrix of
an arterial wall is a critical factor in cardiovascular disease processes.
Matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) degradation
of collagen type IV results in migration and proliferation of vascular smooth
muscle cells; this can lead to further narrowing of a diseased artery. Kinetic
modeling of proteolysis is an approach which can be used to understand complex
systems by describing the enzyme’s mechanism and behavior quantitatively. In
this research project, a computational model of biochemical pathways involved
in activation and inhibition of MMP-2 and MMP-9 proteolysis of collagen type
IV is being developed. Separate MMP-2 and MMP-9 models have been implemented
within JSim, a software application developed by the University of Washington.
Since MMP-2 and MMP-9 pathways overlap, the individual models will be integrated
in the future. This MMP-2 model was also implemented in JDesigner, a tool of
the Systems Biology Workbench, and DEVS, a discrete event system specification,
for comparison of model environments. Various experimental methods for obtaining
quantitative reaction rate parameters were explored, including high pressure
liquid chromatography (HPLC) and florescence polarization. By pairing HPLC
separation, largely by hydrophobic property, with spectrometry techniques,
protein and peptide identification and quantification is possible. Previous
literature suggests the use of HPLC to measure enzymatic activity, by using
traces of the product/substrate itself as an internal standard. An experimental
protocol for the measurement of the enzymatic activity of MMP-2 and MMP-9 is
being developed. HPLC baseline standards for the individual substrates and
enzymes are currently being measured and optimized. After baseline standards
are determined the MMP enzymatic activity can be determined. The HPLC experimental
results will be analyzed to derive the reaction rate parameters needed by the
computational model. The use of HPLC methods to analyze the enzymatic activity
of MMP-2 with collagen type IV and other correlated substrates provides parameters
which cannot be obtained through literature. This research is in collaboration
with the Vascular Research Laboratory at the University of Tennessee Medical
Center in Knoxville.
A Rational Approach for Crystallization of Proteins in Deuterated Media. ALEXIS RAE DEL CASTILLO (California State University,
Chanel Islands, Camarillo, CA, 93012) HUGH O'NEILL (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
Neutron crystallography is
emerging as a powerful tool for the study of protein structure and dynamics.
In neutron crystallography the neutrons interact weakly with the nucleus of an
atom and therefore are a highly penetrating and non-destructive probe. Unlike
x-rays, which interact with the electron cloud surrounding an atom, neutrons
can detect lighter atoms such as hydrogen in the presence of heavier ones and
differentiate between them. The aim of this study was to determine how deuterium
oxide influences the crystallization behavior of proteins compared to crystallization
in hydrogenated media. This will allow a rational design approach for growing
protein crystals for neutron crystallography. In order to achieve this goal a
range of proteins were selected for crystallization studies. Some proteins, such
as aprotinin, cytochrome c, B-lactoglobulin and papain were obtained commercially.
In addition, two variants of GFP, from Aequorea victoria and A.
coerulescens, were over-expressed in Escherichia
coli in
hydrogenated and deuterated media. The recombinant proteins were then purified
to homogeneity by three-phase partitioning and anion exchange chromatography.
The conditions for crystallization of each protein were determined using a high
throughput platform that can screen 1536 different crystallization solutions
simultaneously. Each protein produced crystals in several different solutions.
The conditions that produced crystals were then subjected to a second screening
procedure called Drop Volume Ratio Temperature (DVR/T) to further optimize and
refine the chemical and physical parameters that produced crystals in the initial
screen. A DVR/T phase diagram has been completed for aprotinin, cytochrome c,
B-lactoglobulin A and papain in hydrogenated buffer. Currently, a DVR/T screen
in deuterated buffer is underway for these proteins.
A Rational Approach for Crystallization of Proteins in Deuterated Media. ALEXIS RAE DEL CASTILLO (California State University,
Chanel Islands, Camarillo, CA, 93012) HUGH O'NEILL (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
Neutron crystallography
is emerging as a powerful tool for the study of protein structure and
dynamics. In neutron crystallography the neutrons interact weakly with
the nucleus of an atom and therefore are a highly penetrating and non-destructive
probe. Unlike x-rays, which interact with the electron cloud surrounding
an atom, neutrons can detect lighter atoms such as hydrogen in the
presence of heavier ones and differentiate between them. The aim of
this study was to determine how deuterium oxide influences the crystallization
behavior of proteins compared to crystallization in hydrogenated media.
This will allow a rational design approach for growing protein crystals
for neutron crystallography. In order to achieve this goal a range
of proteins were selected for crystallization studies. Some proteins,
such as aprotinin, cytochrome c, myoglobin, phospholipase and others
were obtained commercially in their purified form. Green fluorescent
protein (GFP) and rubredoxin, were
over-expressed in Escherichia
coli and purified from cell-free extracts. The optimal conditions
for crystallization were determined using a high throughput platform that can
screen 1536 different crystallization conditions simultaneously. Expression of
recombinant proteins was induced with isopropyl ß-D-1-thiogalactopyranoside (IPTG).
The cells were lysed by sonication followed by centrifugation. The proteins were
purified by ion exchange chromatography and size exclusion chromatography. The
purification process was monitored by UV/visible absorption spectrophotometry,
circular dichroism spectroscopy, fluorescence excitation/emission and sodium
dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE). Currently the
1536 screen in H2O
media has been completed for several of the proteins mentioned above and the
experiments to determine how D2O influences crystallization conditions are underway. In addition,
techniques to produce per-deuterated forms of GFP and rubredoxin are being developed
by adapting E.
coli to grow in D2O based media.
A Review of Empirical Methods for the Derivation of Parameters in a Theoretical
Model of Matrix Metalloproteinase 2 & 9 Proteolysis of Collagen
Type IV. ELIZABETH O'QUINN O'QUINN (Wofford College, Spartanburg,
SC, 29303) KARA KRUSE (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Cardiovascular disease
is the leading cause of death in first world countries. An imbalance of matrix
degrading enzymes and structural proteins within the extracellular matrix
of an arterial wall is a critical factor in cardiovascular disease processes.
An increase in matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9
(MMP-9), as part of the inflammatory process, results in degradation of collagen
type IV influencing the migration and proliferation of vascular smooth muscle
cells; this can lead to further narrowing of a diseased artery. Kinetic modeling
of proteolysis is an approach which can be used to understand complex systems
by describing enzymatic
mechanisms, cellular processes, and the system’s behavior quantitatively. In
this research project, a computational model of the biochemical pathways involved
in activation and inhibition of MMP-2 and MMP-9 proteolysis of collagen type
IV is being developed from empirical data and published data. Separate and integrated
models of MMP-2 and MMP-9 pathways have been implemented within JSim, a software
application developed by the University of Washington. In addition to the enzyme
model a cellular migration model is also being developed for the simulation of
VSMC migration and will be explored further. The utilization of reverse-phase
high pressure liquid chromatography (HPLC) methods for obtaining quantitative
reaction rate parameters are being explored for the estimation of parameters
not previously published in the literature. By pairing HPLC separation with spectrometry
techniques, protein and peptide identification and quantification are possible.
Experimental protocols for the measurement of the enzymatic activity of MMP-2
and MMP-9 proteolysis of collagen type IV are being developed to obtain empirical
data. These experimental results are then analyzed to derive the rate parameters
needed in the computational model. The use of HPLC methods to analyze the enzymatic
activity and cellular activity provides parameters which cannot be obtained through
literature. This research is in collaboration with the Vascular Research Laboratory
at the University of Tennessee Medical Center in Knoxville.
AC Losses in YBCO Superconducting Cables. DANIEL
SIMS (Tennessee Technological University, Cookeville, TN, 38505) ROBERT
DUCKWORTH (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
To better supply power
to dense urban areas, superconducting power cables are one solution that can
accomplish
this
within existing electrical ductwork. While "first
generation" Bi-Sr-Ca-Cu-O (BSCCO) tapes are currently being used in several
demonstration cable projects around the world, its cost may limit the market
penetration of commercial superconducting cables. As a potential low cost alternative, "second
generation" Y-Ba-Cu-O (YBCO) tapes have started to meet and exceed the current-carrying
performance of BSCCO tapes with lengths greater than 100 m and could be used
in superconducting cables in the near future. AC loss, which is the amount of
heat generation of a superconducting cable under ac current, is a critical design
parameter since it directly impacts the size of the cryogenic refrigeration system
and thus impacts the overall cost. The goal of this project is to make a technical
evaluation of current YBCO tape architectures, which are currently being supplied
in the United States by American Superconductor (AMSC) and SuperPower (SP). Prototype
cables with lengths of 1.25 m and former diameters of 3.81 cm were made from
the 4-mm wide YBCO tapes to evaluate the effect of the tape architecture on ac
loss. A well-established electrical measurement method and a thermal measurement
method were employed to accurately characterize each cable. A finite element
model was used to make sure that the heater used in the thermal method was sized
appropriately to match the heat generated by the cable. As a measure of the cable
performance, the critical current was measured under dc conditions and was found
to be 5380 A for the AMSC cable and 4400 A for the SP cable, which agreed well
with the single tape critical current for each type of YBCO. With respect to
the measured electrical ac loss at 3 kArms, the AMSC cable was 3 W/m, while the SP cable was 6 W/m. While
this might indicate some advantage to AMSC YBCO tapes, comparing the ac loss
in each cable as a function of the ratio of the peak current to the cable critical
current showed the functional dependence of each cable to be similar as the current
approached 3 kArms. Comparing the ac loss measurement methods, differences between
the thermal and electrical ac loss measurements suggest refinement of the thermometry
is needed and is currently under further investigation.
Agt1 Promoter Sequence Analysis in the Collaborative Cross Parental Mouse Strains. JEANNA KIDWELL (Christopher Newport University, Newport
News, VA, 23606) BRYNN VOY (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
The Collaborative Cross (CC)
is a unique mouse genetic reference population being generated at the Oak Ridge
National Laboratory. This cross will consist of approximately one thousand recombinant
inbred (RI) strains of mice derived from eight parental strains that were chosen
for their genetic and phenotypic diversity. Each strain will contain a unique
combination of alleles from the eight parental genomes, creating a population
with genetic and phenotypic diversity on par with the human population and a
novel resource for the study of heritable disease in humans. We are using the
CC population to study the association between adipose tissue
production of Angiotensinogen (Agt)
on obesity and type 2 diabetes. Agt is the substrate for Angiotensin II, a bioactive hormone that
regulates insulin sensitivity as well as many other physiological processes.
We sequenced the Agt1 promoter
region (about 1.2 kilobases upstream from Agt1) in the 8 CC parental strains in an attempt to identify regulatory
polymorphisms that cause wide variation, up to 100-fold, of adipose Agt mRNA
expression levels across the CC parental strains. DNA was extracted from mouse
ear clips using a modified "Hot Shot" protocol (alkaline lysis followed
by neutralization). The Agt promoter was amplified using Polymerase Chain Reaction with
a series of six oligonucleotide primers. DNA sequencing was performed at the
UTK Molecular Biology Resource Facility. Sequence analysis indicates several
single nucleotide polymorphisms between the strains as well as a three base pair
deletion present in three strains (A/J, NZO, and CAST) and not present in the
other five strains (C57BL/6J, 129, NOD, PWK, WSB). Future experiments will be
directed towards determining the impact of these polymorphisms on Agt transcription.
Air Transport of Commercial Spent Nuclear Fuel (SNF) Assemblies. GIANCARLO
PENA (Florida International University, Miami, FL, 33174) JONATHAN
M. HAIRE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The world is experiencing
transformations as energy prices increase, and nuclear technology is not an
exception. However, the method of transporting spent nuclear fuel (SNF) has
not changed in decades. Currently, in the U.S., SNF casks are shipped by train,
truck, and ship. This work examined the technical feasibility of transporting
SNF casks by aircraft. Air transport of research reactor SNF has already occurred
between countries because of geographical and political reasons. It is concluded
that air transport of commercial spent nuclear power reactor fuel is feasible
in the U.S. with as many as 21 fuel assemblies shipped at one time. The major
constraint that limits the number of SNF assemblies is the lift weight of the
aircraft. This study uses the maximum aircraft payload as 154 tons - the net
payload of the Boeing 747-8 air freighter. Existing casks from different private
companies were analyzed. Sensitivity analyses were performed for transporting
different numbers of SNF assemblies. The smaller the number of SNF casks transported,
the lower the cask weight. Shielding analyses were conducted using ORNL computer
codes CAPSIZE, SCOPE, and SCALE, the objective when using these codes was to
optimize the amount of radiation shielding, while meeting regulatory radiation
dose requirements. Impact crash analyses were conducted with CTH code to demonstrate
crash compliance regulations. Recently, the U.S department of Energy (DOE)
submitted a license application for a permanent geological repository in Yucca
Mountain, Nevada. The cost of air shipments of SNF assemblies to surface storage
for SNF at Yucca Mountain is less than the costs of building the proposed railway
spur to the Yucca Mountain geologic repository. Nuclear power is essential
if the world intends to reduce the levels of greenhouse gases that warm the
earth and by adopting this method of transporting SNF, time and costs will
be reduced.
Analysis of Interstate Weigh Station Viewer Performance. RAMON
COLON MENDOZA (Florida International University, Miami, FL, 33015)
DAVID E. HILL (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
After the 9-11 attacks,
the United States has increased its focus on developing technologies designed
to warn us in the event of another attack, and to prevent these attacks from
happening. The Sensor Net research group at ORNL is participating in this effort
by developing systems to give critical real-time information to federal, state,
and local emergency
response decision makers. Sensor Net’s Southeastern Transportation Corridor Pilot
(SETCP) Project utilizes interstate weigh stations not only to weigh the passing
trucks but also to check for Gamma and Neutron radiation inside the truck without
the aid of a human in close proximity. My role is to characterize and analyze
the data from the South Carolina weigh station on I-26W and the Tennessee weigh
station on I-40 E. The purpose is to find patterns in the truck traffic as well
as to find patterns of inconsistency that the system makes repeatedly. Also I
analyze the improvement after the repairs. Inconsistence patterns are found by
analyzing the data, looking for missing information, and how often it happens.
Traffic Patterns are found by grouping all the data and making graphs and charts
that show the flow of the traffic, the kind of truck traffic, the number of alarms,
as well as other information. It has been found that Monday, Tuesday, Wednesday,
and Thursday the truck traffic is heaviest. Both the component to determine truck
length and the component to read each truck’s license plate were inaccurate,
but have now been fixed as a result of my data
analysis.
Analysis of Meteorological Observations Over the Former USSR, 1950-2000. GARRETT MARINO (Massachusetts Institute of Technology,
Cambridge, MA, 2139) DALE P. KAISER (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Climate change studies require
the processing and analysis of large compilations of meteorological data. Past
studies investigated trends in meteorological variables over the former Soviet
Union using data from a 223-station network spanning 1936-1990. A newly-acquired
update to the database includes data through 2000. The database has been made
available through cooperation between the two principal climate data centers
of the United States and the former Soviet Union: the National Climatic Data
Center, in Asheville, North Carolina and the All-Russian Research Institute of
Hydrometeorological Information - World Data Centre in Obninsk, Russia. Station
records consist of 6- and 3-hourly observations of 25 meteorological variables
including temperature, precipitation, cloud amount and type, pressure, humidity,
and wind speed and direction. The 6-hourly observations extend from 1936 through
1965; 3-hourly observations extend from 1966 through 2000. To ensure high data
quality, extensive quality assurance (QA) checks examined the data for completeness,
reasonableness, and accuracy. We found significant gaps in some records from
observational gaps or measurement values deemed erroneous. Also, World War II
and the breakup of
the Soviet Union affected some records’ completeness. Therefore, this analysis
examined the period 1950-2000 for 125 stations. Total and low cloud amount, frequencies
of various cloud types, and air temperature were all extracted from the dataset
and plotted by station to assess variability and any long-term trends. The results
showed that trends found by previous researchers using data through 1990 have
continued through 2000. Total cloud cover significantly increased (95% confidence
level) at 0.2%/decade despite a significant decrease in low cloud cover of 1.1%/dec.
Meanwhile, low level stratiform clouds significantly decreased by 1.6%/dec and
cumulus clouds significantly increased at 1.4%/dec. Stratiform clouds are associated
with atmospheric stability and frontal passages. A warmer planet and the resultant
reduction of both the meridional temperature gradient and atmospheric stability
may be causing these cloud trends. Air temperature did exhibit a significant
increase of 0.2°C/dec. The Russian database represents a wealth of meteorological
information for a large and climatologically important
portion of the earth’s land area, and should prove useful for a wide variety
of additional regional climate change studies.
Analysis of the Biological Effects of Aspirated Carbon Nanohorn Particles in
Mice using Scanning Near-Field Ultrasound Holography. KATHERINE
VENMAR (Denison University, Granville, OH, 43023) THOMAS THUNDAT (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
Engineered nanomaterials,
because of their enhanced physicochemical properties compared to their bulk form,
are finding an increasingly important role in many potential commercial applications.
However, the health effects of nanomaterials are not well understood or thoroughly
investigated. Therefore, more studies are needed to examine different types of
nanomaterials and the biological responses they invoke. The purpose of this research
was to examine the effects of aspirating single-walled carbon nanohorns (SWCNHs)
in vivo using mice. Bronchoalveolar lavage (BAL) and blood samples were collected
from two experimental groups, the nanohorn exposed, and the control mice. Three
mice from both groups were sacrificed 24 hours and 7 days after aspiration. Gross
examination of the number of macrophages versus activated macrophages in BAL
samples from the exposed and the control mice suggested a possible pro-inflammatory
response to the carbon nanohorns. Employing a unique detection technique, Scanning
Near-Field Ultrasound Holography, carbon nanohorns were discovered bound to cell
membranes, inside cells, and near cells in both the red blood cells and BAL sample
cells. The positioning of carbon nanohorns inside the cells not bound to a membrane
suggests that they entered the cell through a process other than phagocytosis.
Furthermore, the red blood cells (RBC) in all the exposed blood samples exhibited
a distorted phenotype. Such distortions could possibly lead to various pulmonary
diseases. From their ability to permeate membranes, cause pro-inflammatory responses,
and distort the phenotype of red blood cells, it can be concluded that carbon
nanohorns may
pose a biological threat.
Angiotensinogen Expression in Collaborative Cross Offspring. ADAM LUNDQUIST
(Christopher Newport University, Newport News, Va, 23606) BRYNN H. VOY
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Collaborative Cross (CC)
is an emerging population of recombinant inbred (RI) lines of mice designed to
untangle complex webs of genetic interactions. The CC, now being implemented
at Oak Ridge National Lab (ORNL), is being created from 8 diverse inbred strains
of mice bred to produce 1000 RI strains, with every resulting strain containing
a portion of the genome from each of the 8 parental strains. The genetic and
phenotypic diversity of these 1000 RI strains will model that found in human
populations, making the CC a valuable resource for dissecting the genetic contributors
to complex traits such as obesity and hypertension[1]. This diversity, coupled
with the known genotypes of the animals, will be utilized to map and dissect
the genetics of complex traits, which are phenotypes produced from the interaction
of multiple genes. We are interested in obesity a complex trait involving many
genes interacting within multiple metabolic pathways. One such gene known to
play a role in both obesity and hypertension is angiotensinogen, Agt. Agt is
a vascular constrictor expressed in adipose tissue; its expression varies widely
among the eight CC parental strains. In order to study Agt expression in the
intermediate CC generations, those whose genomes have yet to be fixed by inbreeding
(strict brother-sister mating for 20 generations), we extracted RNA from adipose
tissue, reverse transcribed it into complementary DNA (cDNA), and utilized quantitative
Polymerase Chain Reaction (qPCR) techniques to determine mRNA expression levels.
Agt expression levels ranged widely (~ 15-fold) across the sampling of CC mice,
indicating tha the diversity of this molecular trait in CC mice reflects that
of a human population. Our results provide insight into the effects that mixing
diverse genetic backgrounds have on Agt expression in these RI mice and will
lead to future mapping of genomic
loci involved in complex
metabolic traits.
Application to Determine and Control Twiss Parameters of the SNS Accelerator
Beam. JENS VON DER LINDEN (University of Pennsylvania, Philadelphia,
PA, 19104) SARAH COUSINEAU (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
The accelerator ion beam
at the Spallation Neutron Source (SNS) is repeatedly focused and defocused
by a series of quadruple magnets as it travels to the target to create neutrons
by means of spallation. Physicists are interested in characterizing the accelerator
beam in order to understand and improve the focusing and transport of the beam.
Wire scans are employed to measure the traverse density profile of the beam.
With a minimum of 3 distinct wire scans, the ion beam Twiss parameters, which
characterize the phase space properties of the beam, can be determined. In
this project, a Graphical User Interface (GUI) Application was developed in
JAVA to automate the determination of Twiss parameters from the wire scan data
files and to determine how quadruples should be varied to change the Twiss
parameters at multiple arbitrary locations. The software is coded within the
XAL framework, an existing JAVA library developed at the SNS accelerator which
is used for all GUI-based physics software applications. A major contribution
of the JAVA GUI developed in this project is that it is generally applicable
to any area of the accelerator containing a minimum of 3 wire scanners. Existing
applications were tied to specific parts of the accelerator. Twiss results
can be saved and compared through graphing and averaging. As the SNS is a high
intensity accelerator which requires strict control over the beam losses, it
is very important that the beam in the accelerator be transported according
to the optimum design configuration. Any deviation from the optimum transport
configuration can lead to beam loss that can limit the obtainable beam power
in the accelerator. This application will aid in measuring the beam state at
any point in the accelerator, and will subsequently allow a user to make adjustments
to the beam state in order to restore the optimum configuration and ensure
well
controlled beam transport.
Bending Kirkpatrick-Baez Mirrors for Neutron Focusing. ANTHONY
FIELDS and JAY PATEL (South Carolina State University, Orangeburg, Sc,
29117) DR. GENE E. ICE (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Neutron scattering is useful
for analyzing the atomic structure and defect density of materials. Because neutrons
have spin, an isotope-dependent scattering cross-section and are penetrating,
neutron beams are particularly well suited for the study of magnetic materials,
bulk materials and for the study of low Z or mixed Z structures. Several techniques
for directing a beam of neutrons to a sample are available. While guide tubes
and collimators work well for large sample sizes, focusing becomes increasingly
important as the neutron probe dimension and sample sizes become small. The importance
of high-performance nondispersive focusing optics for neutrons has just recently
been recognized. In micro-focus experiments, we consider the need for convenient
wavelength tuning and/or broad bandpass beams. This favors achromatic methods
based on specular reflection. The Elliptical Kirkpatrick-Baez (KB) scheme offers
the best flexibility and neutron gathering power, and can nondispersively image
neutrons to small spots with high intensity and source-limited brilliance. The
KB geometry uses crossed mirrors in grazing-incidence. With perfect elliptical
KB mirrors, spherical aberration can be eliminated. We have adopted techniques
for producing elliptical neutron mirrors by controlled bending. The need to control
the slope errors in the mirrors is very important. The mirrors, the bending control
mechanism, and supports are integrated as a unit. Both mirrors are attached to,
and bent by a leaf spring mechanism. We have used a laser beam to simulate a
thermal neutron beam for system calibrations; we determine the radius of curvature
of the mirror as a function of bender settings (coupling force). Results show
changes in the focal length (and subsequently in the radius of curvature) with
micrometer setting. From these results we can determine the optimum radius of
curvature of the mirrors for minimum slope errors. The mirror in the vertical
plane sags under gravity and therefore, introduces a mixture of defocus and spherical
aberration. We have designed passive corrections by a series of springs under
the mirror. A computer program has been written to calculate the gravitational
curvatures and slope errors as a function of the number of support springs and
loading conditions. Simulation results show that the effect of one spring alone
reduces the slope errors by a factor of 10 and with three spring supports, slope
errors are reduced by over a factor of 100.
Binding Superhydrophobic Powder to Surfaces for Dielectric Purposes. MARY HADLEY (Vanderbilt University, Nashville, TN,
37235) ENIS TUNCER (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Outdoor insulators used in
high voltage transmission lines and substations are constantly under environmental
stress leading to power interruptions, flashovers, etc. One common occurrence
in polluted areas is excess water collecting on insulators promoting dry band
arcing. It has been shown that hydrophobic materials are the solution to avoiding
this event. These materials do not interact with water molecules forcing them
to bead up instead of collecting into films. This unique surface quality also
makes the hydrophobic materials self-cleaning in wet environments. Traditional
hydrophobic materials for outdoor insulation have been silicone rubber based
materials. Recently other material formulations with fluor based compounds have
been proposed. In this study, a superhydrophobic (SH) material made of a glass-based
powder is investigated. The material alone does not adhere to surfaces, so research
was performed to find a polymer that will bind the particles to a surface while
maintaining SH qualities. Test surfaces were prepared by making six solutions
of SH powder, a binder, and an alcohol solvent and then dispensing the solution
onto plastic and glass slides. Binders tested were polyvinyl butyral resin (PVB),
polymethyl methacrylate (PMMA), Rhoplex Fastrack X-tended Seasonal Range resin
(XSR), and Araldite resin. Hydrophobicity was tested by measuring the radii of
water droplets to calculate contact angles and wettability by recording radii
of droplets over time. The surfaces were also observed for scratch resistance,
adhesion, and cohesion.
Three mixtures showed high angles of approximately 130° to
133°. PVB surfaces had high wettability and poor cohesion, and surfaces made
with a higher ratio of binder had poor adhesion. The resin and XSR surfaces maintained
some scratch resistance. These tests prove the best surface investigated in this
research is made with 0.8g of SH powder and 0.4g of XSR. It repels water for
an extended time and maintains the highest contact angle at 133°. This surface
is not deemed SH because its contact angle is below 150°, but this mixture is
most able to remain hydrophobic. The particle mixture forms a consistent film
and adheres well to surfaces, but only fair scratch resistance makes it imperfect
for potential application. These results are part of ongoing research to determine
polymers that bind to particles and withstand environmental conditions experienced
in polluted areas.
Collaboration and Implementation of Disruptive Technologies in the Emergency
Response Environment (I-ReSCUE). CARTER
DEDRICK (University of Memphis, Memphis, TN, 38105) DONALD E. VINSON
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Emergency response operation
and networks are naturally collaborative in nature; however, due to recent catastrophic
events and legislation, these networks have been encouraged to become more centralized.
There is ongoing research at Oak Ridge National Laboratory involving the adaptation
of existing technologies to National Security solutions. The goals for my part
of the project are to describe ways in which beneficial Disruptive Technologies
act as a decentralizing force within the emergency response environment on a
local level, diagram the overall emergency response environment and propose a
theory for an improved planning and response tool. This is accomplished through
literature review, interviews, and analysis of current response tools available.
Research was conducted to develop theory for an interactive emergency response
program to be constructed on an existing platform and explore how Disruptive
Technologies can best be utilized. Compartmentalization of resources within emergency
response cultures result in slow growth of innovations within the emergency response
environment. Research into the connections of these networks is mapped and the
ideal response network discussed. Requirements include management of interagency
agreements, the ability to expand vertically and horizontally as needed for response
to changing events, and include non-profit representatives. Collaboration in
emergency response networks is currently carried out, and can be mapped on vertical
as well as horizontal axes. The vertical collaboration axis begins with the local
EMA (emergency management agency) and expands upward as the events grow larger
to include the state and Federal EMA. The horizontal collaboration axis shows
the relationship between nonprofit and other NGOs (non-governmental organizations)
to the vertical collaboration within the public sector EMA. Collaboration is
best facilitated by policies that allow responders to create connections as opposed
to those that merely limit abilities. Disruptive Technologies must be embraced
and utilized on a wide and daily basis in order to be of any use in the event
of an emergency.
Computational Development of H- Ion Sources for the Spallation Neutron Source. JUSTIN CARMICHAEL (Worcester Polytechnic Institute,
Worcester, MA, 1609) ROBERT F. WELTON (Oak Ridge National Laboratory,
Oak Ridge, TN, 37831)
The US Spallation Neutron
Source (SNS) requires a high power H- ion source in order to achieve the desired
neutron flux. Over the next several years, the SNS will require substantially
higher average H- beam current than can be produced from conventional H- ion
sources including our baseline source. H- currents of 70-100 mA with an RMS emittance
of 0.20-0.35 mm mrad and a ~7% duty-factor will be needed for the SNS power
upgrade project. Presently, external antenna sources, based on Al2O3 plasma chambers,
have been developed which have been shown to produce beam currents of 25-35 mA
with a duty-factor of 2-3%. Computer simulations employing the Finite Element
Method (FEM) with coupled fluid dynamic, heat transfer, and thermal stress and
deformation capabilities have been performed to investigate the design of the
plasma chambers operating at higher duty-factors. These simulations show that
a plasma chamber made from AlN can be designed to meet the full duty-factor requirement.
In order to meet the beam current requirements, efforts are being made to (i)
increase source plasma density by using magnetic confinement and (ii) improve
the efficiency of ion extraction from the plasma. Towards these ends simulations
are being performed using LORENTZ for magnetic field modeling and COSMOS for
thermal analysis of the electron dumping electrode. An AlN plasma chamber, a
solenoid confinement magnet and an electron dumping electrode have been designed.
It is anticipated that substantially greater beam currents can be achieved with
these improvements
to the ion source.
Control of Carbon Nanofiber Alignment During Growth in Plasma Enhanced Chemical
Vapor Deposition Processes. RYAN PEARCE
(University of Tennessee, Knoxville, TN, 37916) MICHAEL SIMPSON (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
Carbon nanofibers are just
recently coming under scrutiny with a number of potential uses such as gene delivery
arrays
and neuronal interfaces. Nanonofibers have
a stacked “herringbone” structure, giving them a very high aspect ratio, which
is what lends them such a great range of possible applications. Carbon nanofibers
are typically grown using a process called “Plasma Enhanced Chemical Vapor Deposition” (PECVD).
In this process, a silicon wafer with nickel deposited on it in a specific pattern
is placed on a heater in a vacuum chamber. The heat is turned on and ammonia
(NH3) and Acetylene (C2H2) are introduced into the chamber at a specific pressure
and flow rate. A plasma is induced which causes the carbon from the C2H2 to deposit
on the nickel dots, forming the carbon nanofibers. This process forms vertically
aligned carbon nanofibers. Our project aims to find a technique to control the
alignment of the nanofibers during growth. The way we do this is by changing
the method whereby gas is introduced into the system. Classically, the gas flows
into the chamber perpendicular to and far away from the surface of the wafer,
so that only the ratio of gases affects the growth, and not the flow rate. What
we do is place a nozzle directly over the wafer so that the gas flows directly
over it. We devise an optimal regimen for growth where we only vary the total
flow, keeping the ratio of gases constant. After growth, we observe the wafer
under a scanning electron microscope. We have found that nanofibers respond to
the variations in flow by tilting along the flow. There are some aspects of this
study that require further investigation. First, we need to determine the correlation
between angle of tilt and flow rate, which can be done by setting up a series
of experiments keeping the total flow variable in a stepped sequence and measuring
the resulting angle formed by the nanofibers and the substrate. Then, flow ratio
needs to be varied to determine the resulting effects. Another method of creating
tilt in nanofibers is through variance in the electric field during PECVD. Towards
the edge of the field, this causes the nanofibers to “bend.” This technique is
impractical, however, as only the fibers grown on the very edges of the field
are affected. Our study is fundamental in understanding how to control nanofiber
growth, which will lead to an overall better understanding
of nanoscale fabrication.
Cyber Security at Oak Ridge National Laboratory. BOBBY
SWEET (Roane State Community College, Oak Ridge, Tn, 37840) VICTO HAZLEWOOD
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Office of the Chief Information
Officer (OCIO) has the responsibility to ensure that all information technology
(IT) is managed to all statutory, regulatory, and organizational requirements
which can be found in the Certification and Accreditation package which documents
the Oak Ridge National Laboratory (ORNL) Cyber Security Program Plan. In the
case of ORNL, who has over ten thousand computer systems, there are systems that
will not comply with these standards for a variety of operational and other reasons.
The OCIO ensures that computing resources are managed to requirements with some
mitigation in place for systems where the requirements could not be met. In many
cases, a security plan will provide the basis for the mitigation for systems
or collections of systems that cannot meet all the requirements. Security planning
was our main emphasis this summer. There were approximately two-hundred forty
systems at the start of this summer that needed a security plan in place, if
they were going to stay on the ORNL network. A process needed to be developed
and implemented to address the two-hundred forty systems and their required security
plans in the most efficient manner within a limited amount of time. Four security
planning meetings were given to communicate the security planning process. It
is expected that these meetings will be held each month to keep up with new systems
that might not meet requirements and require a security plan. Three questionnaires
were created for the different control categories to help the owners of the devices.
The three different control categories were moderate with enhanced, moderate,
and low. The categories are determined by the sensitivity of information each
of these systems would hold (moderate with enhanced requiring the most controls
of the three). The classes have been completed and the resources have been distributed
to the system owners and administrators to start their security plan process.
The ORNL security planning project has been developed and is being implemented.
The security planning process will continue to be improved in the effort to protect
the devices that are not able to satisfy all cyber security requirements. This
project is designed to protect the devices making them as safe as possible from
intruders or unauthorized access by providing a mitigation strategy when a device
cannot implement one or more required cyber
security requirements.
Design for Increased Functionality of the Hot Cells inside the Radiochemical
Engineering Development Center. BRENT
BEATTY (University of Tennessee, Knoxville, TN, 37916) JEFFREY BINDER
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Radiochemical Engineering
Development
Center (REDC) has been the United States’ main production center for transcurium
elements since operations began in 1966. Together with the neighboring High Flux
Isotope Reactor (HFIR) these facilities produce transuranium elements for commercial
and research purposes. The facilities’ technologies and capabilities gained through
a vast production history allow for an ideal test bed for Global Nuclear Energy
Partnership’s (GNEP) Coupled End to End (CETE) demonstration. The purpose of
the demonstration is to perform mechanical and chemical processes on actual spent
nuclear fuel, which will confirm the projected material flow and performance
data and with extensive experimental data. While the specialized support infrastructure
for hot cell processing has been in place for forty years, there are still design
improvements to the current operational flow necessary to fully accommodate all
aspects of the demonstration and to enhance future capabilities of the facility
to attract new projects. Many of the cubicles have not been updated in several
years and were designed primarily for targets and fuel elements from HFIR. The
CETE demonstration will be performed on many different fuel pins and assemblies
from many reactor designs. In order to accommodate this larger variety of experimental
components, I designed and
coordinated fabrication of a new "disconnect well" and the associated "containment
thimble" for the remote hot cell welder. These modifications will double
the length of components that may be processed in the hot cell. This design adds
functionality and increases the flexibility required to process the diverse fuel
components with minimal impact on the safety specifications and operational requirements
and uses materials that did not require new certification for use in REDC. Due
to the increased load that will be on the "disconnect well" flange,
a calculation was made confirming the ability of the new design to support the
added load. The increased moment of the assembly required an updated seismic
analysis which was performed and documented in the facility handbook. As the
world accepts Nuclear Energy, facilities like REDC have an important and unique
role in demonstrating and validating new advanced chemical processes. There are
many additional updates and improvements that will have to be made similar to
the redesigned "disconnect well" discussed here in order to fully modernize
this key facility.
Designing and Implementing Graphical User Information (GUI) Components for
the Automation of the Analysis of RTBT Wire Scanners' Data. KARLA
WARD (Tennessee State University, Nashville, TN, 37209) TED WILLIAMS
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Spallation Neutron Source
(SNS) located at Oak Ridge National Laboratory (ORNL) is home to the world's
highest-energy-pulsed H-ion particle accelerator. The accelerator sends an
intense proton pulse to a heavy atomic nucleus of mercury to produce neutron-scattering.
Within the accelerator complex are five different sections that work together
to result in this neutron-scattering: the linac, the high energy beam transport
(HEBT), the ring, the ring to target beam transport (RTBT), and the mercury
target. The Linac accelerates the beam to 90% of the speed of light. The HEBT
transports the beam from the linac to the ring. The ring stores the protons
and the RTBT transports the beam to the mercury target, which gets bombarded
by the beam at 60 times per second. The RTBT region of the accelerator is of
particular importance currently because this is where data is taken that relate
to the size and horizontal and vertical position of the beam before it reaches
the target. Wire scanners perform the process of taking the data from the RTBT
and placing it into a file to be analyzed, and with the help of a computer
program the operators of the accelerator analyze this data. To speed up the
analysis of data from the RTBT wire scanners, the analysis program rtbtwizard
was modified to improve and enhance the functionality between the user and
the data processing routines. Specifically these modifications included the
addition of “Cut, Fit and Store All”, “Percent Range”, “Noise Subtraction”,
and “Clear Data Table” buttons into an already existing panel. The activation
of these buttons produce a series of actions which include automatic Gaussian
fitting, storing analyzed data, finding and eliminating the noise floor, and
clearing the data table. These modifications resulted in a more efficient procedure
for the operators of the accelerator to analyze the size and position of the
beam on the target. This in turn improves the probability that there will be
a reduction in activation at the target, damage to the nose cone of the target,
and ensure maximum neutron production.
Determining the Ability to Monitor the Viability of Transplant Rat Glioma Cells
with an Optically Enhanced Catheter. RACHEL
DYER (St. Olaf College, Northfield, Minnesota, 55057) BOYD M. EVANS
III (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Approximately fifty thousand
cases of Parkinson's Disease are diagnosed within the United States each year.
This debilitating disease results from the dissolution of dopamine-dependent
communication between the substantia nigra and the striatum of the brain. Cellular
replacement therapy, in which stem cells are introduced to supplant dead or stressed
cells, has shown promise in animal models. However, the viability of transplanted
cells and their survival rate is poorly accounted for by early tests. A novel
design coupling a surgical catheter with fiber optic technology provides a tissue
delivery platform that can monitor cell viability with sensing techniques widely
accepted in the medical industry. The goal of this work is to monitor the health
of transplant cells in real time at the final point of delivery using the optically
enhanced catheter. Rat glioma cells were separately labeled with CellTracker
Orange (CTO)
(Invitrogen) and JC1 stain from
BioVision’s MitoCapture Mitochondrial Apoptosis Detection Kit and fluorescence
was characterized by confocal microscopy. CTO exhibited a single emission peak
at 570 nm upon excitation with a 488 nm argon laser. JC1 exhibited two emission
peaks corresponding to fluorescence of viable cells and apoptotic cells, 595
and 540 nm respectively. JC1 was used to monitor the viability of cells under
apoptotic conditions induced by incubating JC1-labeled cells with carbonyl cyanide
3-chlorophenylhydrazone or etoposide. Observation of fluorescence using a mercury
fluorescence microscope over a four hour period demonstrated JC1’s ability to
shift in color to reflect cell viability. To detect cell movement through the
catheter, cells were labeled with CTO, excited by an argon ion laser with a 501
nm wavelength and a peak emission at 570 nm was detected by an Ocean Optics spectrometer.
JC1 was also used to detect the movement and the viability of cells through the
catheter. Cells excited by an argon ion laser with a 488 nm wavelength exhibited
emission peaks at 540 and 595 nm, demonstrating the ability to detect both viable
and apoptotic cells at the final point of delivery. From the detection of rat
glioma cells labeled with CTO and JC1 using the diagnostic catheter, and the
characterized response of JC1-labeled cells to apoptotic conditions, it can be
concluded that these fluorescent probes are suitable for tracking and monitoring
the viability of transplant cells through the optically enhanced catheter.
Determining the Optical Properties of Biological Tissue Samples Using an Integrating
Sphere Method. MARCUS ALLEGOOD (North Georgia
College & State University, Dahlonega, GA, 30553) JUSTIN S
BABA (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Wavelength dependent
light interaction with biological tissue can be described using three parameters:
the scattering and absorption coefficients and the cosine of the average
scattering angle (g). To accurately determine these optical properties for
different types of tissue at specific wavelengths would be beneficial for
a variety of different biomedical applications. The goal of this project
was to take a user defined g-value and determine the remaining two parameters
for a specified range of wavelengths. In order to collect the needed data
for all the wavelengths in a timely and accurate manner, a fully automated
computer program and process was developed. Using a single integrating sphere
method, scattered light intensity inside the sphere was recorded via a spectrometer
as either transmitted or reflected light from the tissue sample. LabVIEW
was used to write programs to collect raw intensity data from the spectrometer,
to convert the data into a format for C code execution, and to compute the
optical properties based on the collected data. To make the process fully
automated, the LabVIEW and C code programs were linked together into one
single program to allow data to be passed between the two efficiently. The
automated program was tested using a tissue mimicking phantom and determination
of the absorption and scattering coefficients showed excellent agreement
with theory. Future work and the final phase of testing will entail examining
actual biological tissue with known optical properties to check for accuracy
before proceeding to utilize the system for its intended purpose. Ultimately,
the data collection process and algorithms developed through this effort
will be applied to build models for light interaction with biological tissue
samples.
Developing a Proof-of-Concept CyberInfrastructure for the USA National Phenology
Network. BENJAMIN CROM (University of Tennessee, Knoxville,
TN, 37916) BRUCE E. WILSON (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Phenology is the study
of the timing of naturally recurring events, such as flower blooming, particularly
those influenced by environmental changes. Phenological measurements are extremely
valuable indicators of local, regional, and global climate changes. Further,
phenological variations have a variety of crucial environmental and socio-economic
implications. Despite this value, broadly distributed phenological measurements
are almost non-existent in the USA, in contrast to some European countries.
The objective of this work is to explore and evaluate different data models
and data management methods needed for the development of the cyberinfrastructure
for a new data resource: the USA National Phenology Network (USA-NPN). The
USA-NPN will create a national repository for submitting and retrieving a wide
range of phenological data, including data from existing research networks
and from citizen scientist observers. For this project, we have been focusing
on the data model and information management tools necessary to support the
citizen scientist aspect of USA-NPN, based on existing work from the Plant
Phenology Network (PPN). A key feature at this stage of the program is for
citizen scientists to enter phenological observations on any of the 38 species
currently in the PPN. The USA-NPN will also require basic tools for observers
to retrieve their own data and the publicly available data. We have created
a simple but flexible database schema which we are testing against a range
of ways the system may be used. This schema is an improvement over the current
PPN tools, which use separate text files for each species. We are also working
on improving the registration and authentication processes. The user is now
able to create login credentials and submit personal contact information without
PPN staff intervention. This reduces staff load and the revised data entry
forms greatly improve the tracking of data provenance. Our current work will
improve session management operations and may enable OpenID authentication.
We intend to streamline the maintenance of data submission pages by eliminating
the current 38 separate submission pages in favor of one master submission
page driven by the underlying database. We will also add a data retrieval page
which will give users access to public phenology data. The data offered by
this network will contribute to a better understanding of climate change and
help engage citizen
scientists in climate change science.
Development of 40% Energy Saving Home. JACOB
BONAR (University of Tennessee, Knoxville, TN, 37916) JEFFREY E. CHRISTIAN
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The demand for energy continues
to rise throughout the world. One place that everyone can reduce energy consumption
is in their home. This is especially true of new homes built with energy efficiency
in mind. The goal of my research is to show that a new home can operate with
a total energy savings of 40%. The major areas to look closely at are building
tightness, appliances installed in the home, and the proper sizing of the HVAC
(Heating, Ventilation, and Air Conditioning) system. I will gather the necessary
data to prepare a report for the fifth Zero Energy Home, ZEH5. The report concerning
only the top floor of ZEH5 will cover how to build a house that has an energy
savings totaling 40%. Included in the report detailing ZEH5 will be my write
up describing the HVAC sizing using Manual J 8th Edition analysis, which I will
conduct for ZEH5. I will work with Jeff Christian to measure and document the
airflow rates in ZEH5 distribution system using a flow hood and the whole house
air tightness using a blower door. In addition to these sections, an Energy Gauge
packet will also be included in the documentation. One major part of the Energy
Gauge packet and associated write up will be a comparison between the ZEH5 and
the Building America benchmark home. After looking at the energy consumption
for a physical year, ZEH5 consumed a daily average of $0.66/day. This is lower
than ZEH1-4 homes that consumed between $0.75-$1.01. Two more homes are in development
that will continue the research towards a true Zero Energy
Home.
Development of a Mathematical Model for Intimal Hyperplasia due to Vascular
Injury. NATHAN SUMMERS (University of Tennessee, Knoxville,
TN, 37916) RICHARD WARD (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Intimal hyperplasia (IH)
is the thickening of the arterial wall in response to an injury of the blood
vessel. IH results from the migration of vascular smooth muscle cells (VSMCs)
from the medial to the intimal layer of the blood vessel wall and is believed
to be directed by biochemical concentration gradients, a process known as chemotaxis.
The primary chemotactic biochemical appears to be platelet-derived growth factor
(PDGF) which is produced by platelets adhering to the arterial wall and macrophages
invading the intima. The induced migration can be quantified using individual
cell tracking or through cell population assays. The parameters for individual
cell assays, such as average cell speed and persistence time (the average amount
of time the cell takes before it changes direction), can be related mathematically
to the parameters of the cell population assays, such as the random motility
coefficient (similar to a Brownian diffusion coefficient) and the chemotaxis
coefficient (the directed diffusion coefficient). One of the goals of this research
was to quantify this relationship using data obtained through literature searches
and data obtained from experiments conducted by the Vascular Research Laboratory
(VRL) of the University of Tennessee Graduate School of Medicine, Knoxville.
However, the needed data from the VRL has not yet been made available, making
it impossible to fully quantify the algebraic model for this relationship. It
is also believed that the receptors on the cell surface of VSMCs play a key role
not only in detecting but also in processing the information from the PDGF biochemical
gradient. The second goal of this research was to incorporate VSMC receptor mechanics
into a hybrid model (a combination of a discrete model for cellular migration
and a continuous model for biochemical diffusion) of VSMC migration driven by
chemoattractants. This was accomplished by writing a C++ code modeling the role
cell receptors play in the cellular response due to the effect of PDGF. The ultimate
goal of this research is to augment a hybrid cell migration model with receptor
mechanics to study the possible deleterious affects of balloon angioplasty and
the effects of hormone replacement therapy on the
outcome of this procedure.
Development of a Visualization Program Used in Computational Simulations of
Nanomaterials. JANA BLACK (University of Tennessee, Knoxville, TN,
37916) PETER CUMMINGS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Nanoscience offers many scientific
opportunities; it also poses significant experimental challenges since it deals
with matter in the size range of 1 to 100 nanometers. Theory and simulation are
crucial to nanoscience since experimental measurements and observations made
at the nanoscale are often impossible to interpret without a theoretical model.
Oak Ridge National Laboratory's (ORNL's) Center for Nanophase Materials Sciences
(CNMS), in particular the Nanomaterials Theory Institute (NTI), is involved extensively
in the development of programs and tools for nanoscale simulations at various
time and length scales. NTI maintains a high-performance visualization cluster
and 16-node visualization wall in addition to its multi-teraflop computational
clusters. The goal of this project is to develop a complex tool that can be used
to visualize, at high resolution, the trajectories obtained from various types
of molecular modeling such as ab initio, molecular dynamics, or Monte Carlo.
The specific data used as an example in this study is from molecular dynamics
simulations of pulling apart a gold nanowire. My role in the project is to write
a program to drive two major visualization packages which are already installed
on the NTI visualization clusters, VisIt and Visual Molecular Dynamics (VMD),
so that high-resolution animations can be created from the simulation trajectories.
VisIt is designed to visualize very large parallel data in the terascale range.
VMD is designed to visualize molecular biological systems. Neither program is
ideal for this project, but both encourage users to modify the source code and/or
write scripts so the program will better meet their needs. In this particular
study, it was considered best to run the visualization simultaneously with 16
copies of either VMD or VisIt, one per node, using 16 sets of simulation data
collected at various conditions. I have written scripts to synchronize them.
The scripts label the atoms according to their instantaneous temperatures and
vividly display the evolution of the system. The visualization helps to interpret
the physical process of pulling apart a gold nanowire at the molecular level.
This project serves as a trial step in the molecular visualization of complex
systems using the NTI facilities; it is one step toward the ultimate goal of
developing comprehensive simulation and animation tools of various stages at
CNMS to interpret/guide experimental efforts.
Development of an ASTM Graphite Oxidation Test Method. TYLER
GULDAN (The University of Tennessee, Knoxville, TN, 37996) TIMOTHY
D. BURCHELL (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Graphite, one of the
three allotropes of carbon, is a very useful material because of its unique
chemical structure and properties such as mechanical strength, chemical inertness,
and electrical conductivity. In order to advance our knowledge of various
graphite brands, further research must be conducted to gain a greater insight
into the process and effects of oxidation on graphite properties. Although
the key processes and controlling elements of graphite oxidation have been
identified, the behavior of this material during and after oxidation is not
well established. Knowledge of this behavior is crucial in understanding
what happens to the various graphite components in nuclear reactors. Thermogravimetric
analysis in a vertical furnace of large samples of NBG-18 graphite at the
Oak Ridge National Laboratory (ORNL) has been used to characterize the oxidation
resistance of this material, and to increase the scientific understanding
of the relationship between the rate of oxidation and the flow rates of gases,
temperature, and the intrinsic reactivity of graphite. This helps to identify
the more oxidation resistant forms of graphite. In addition, comparative
analysis of data collected on other graphite materials has been conducted,
in order to identify a more expedient procedure for analysis of graphite
oxidation data. The information gathered from these experiments and calculations
is geared towards the development of an American Society for Testing and
Materials (ASTM) test method for the oxidation of graphite. More research
on all of the types of graphite is needed, but such results suggest that
the current ORNL procedure using the vertical tube furnace may become a reliable
ASTM test method.
Development of Integrated PV Reporting System. MARIANO
PADILLA (Fullerton College, Fullerton, CA, 0) WILLEM BLOKLAND (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
The Spallation Neutron
Source (SNS) at Oak Ridge National Laboratory is a state of the art accelerator-based
neutron source. Neutron-scattering research helps develop new materials for
superconductors, magnets and plastics. SNS uses a hydrogen ion pulse beam to
bombard a mercury isotope target to produce the neutrons. Operators control
the accelerator complex by using console screens that can display and set Process
variables (PV) from the Input/Output Controller (IOC) devices. Reports on the
statistics of the accelerator operation are needed to evaluate the performance
of the accelerator. Providing time sensitive and accurate reports of the overall
health of the accelerator in an automated, efficient and intuitive manner is
an important necessity. The reporting system requirements are to provide an
intuitive multi-platform and web-browser based user interface, integration
with Oracle, e-mail systems and Portable Document Format (PDF) generation.
The reporting system provides the user with a web-based interface to setup
specific PVs to acquire, how to process, and how to publish the results. An
integrated reporting system is developed using PHP, Java, Javascript, Java
Server Pages (JSP) and Business Intelligence and Reporting Tools (BIRT) for
ECLIPSE Integrated Development Environment (IDE). The Oracle database already
in production use at SNS is the primary storage location for the data collected
from the PV’s at a rate up to 1Hz. The integrated reporting system will provide
physicists, operators and engineers with a simple platform to monitor, analyze,
and report on the operation of the SNS accelerator.
Effect of Chemistry Variations on the Microstructure and Mechanical Properties
of Creep Strength Enhanced Ferritic Steels. KEELY
WILSON (Michigan Technological University, Houghton, mi, 48128) JOHN
SHINGLEDECKER (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Grades 91, 92, and 122
steels (9-12% Chromium) are known as Creep Strength Enhanced Ferritic steels.
These grades of steel are finding increased usage in the pressure retention
components of advanced fossil energy systems (Ultrasupercritical Steam Boilers,
Heat Recovery Steam Generators, etc.) because of their superior performance
in high temperature, high stress environments. The chemical specifications
for these grades are very broad, which may affect the mechanical properties
and long-term performance of the alloy in service. Ideally in the normalized
and tempered condition, Gr 91, 92, and 122, will have fully martensitic structures
with no ferrite forming. In an earlier study, two compositions of each grade
were produced by varying the amounts of austenite formers (C, Mn, Ni, N) and
ferrite formers (Si, Cr, Mo, V, Nb) within the current specification range.
These chemistry changes were guided by computational thermodynamics to alter
the intercritical temperatures, the temperatures at which steel changes phase,
and to cause the formation of ferrite under standard processing conditions.
In this study, the mechanical properties of these samples were evaluated, and
are compared to literature results for commercially produced material. High
temperature (650°C) creep tests were run with loads ranging from 100 to 140
MPa for times exceeding 1000 hours. Tensile tests were run at both high temperature
(650°C) and room temperature (25°C). Digital Imaging software was used to analyze
the steel microstructures to determine the amount of martensite and ferrite
present in each alloy. It was found that both the tensile strength and the
creep strength of the alloys decreased substantially with the presence of ferrite
in the material. This critical finding clearly shows that the specification
range for these alloys is too broad which may result in commercially produced
materials with properties far from expectations. A limited evaluation of thermodynamic
predictions and microstructural findings was also conducted. The data collected
in this study, combined with data from other tests, such as long term creep
tests, thermo-mechanical simulation, and thermodynamic modeling will later
be used to
create more specific standards for Gr 91, 92 and 122 alloys.
Effect of Oxygen Annealing on Substrates for Complex Oxide Film Growth. RYAN SMITH (Case Western Reserve University, Cleveland,
OH, 44106) HANS CHRISTEN (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
In this investigation, the
optimum annealing conditions (temperature and atmosphere) yielding atomically
flat surfaces on the crystalline material NdGaO3 were examined. This material
is used as substrate for thin-film pulsed laser deposition (PLD) of various complex
oxide films, including, for example, Yttrium Barium Copper Oxide (YBCO), a high-temperature
superconductor (HTSC) based on the perovskite crystal structure. Since their
discovery over 20 years ago, HTSCs have been thoroughly investigated because
they exhibit superconducting properties (zero resistance) above the boiling point
of liquid nitrogen (77 K). Thin films of these materials have shown improved
superconducting properties, which are highly dependant on the defect structure
of the film. Recently, new complex oxide substrates for YBCO deposition have
been investigated, including LSAT ((La,Sr)(Al,Ta)O3) and NdGaO3, because of their
similar thermal expansion coefficient, good dielectric properties, and small
lattice parameter mismatch with YBCO compared to traditional sapphire substrates.
Such a perovskite substrate with atomically flat terraced surface terminated
in regular unit-cell high steps is essential for high quality epitaxial YBCO
films with low or controllable defect density and optimal superconducting properties,
as well as for other metal-oxide films (ferroelectrics, colossal magnetoresistive
(CMR) materials, etc.). Perovskite-type ABO3 crystals with at least two cation
species, like NdGaO3, can terminate in
either “A-site” (AO)
or “B-site” (BO2) layers on the crystal surface. Unlike most substrates considered
for oxide film growth (e.g. SrTiO3), thermal annealing of NdGaO3 results in an
A-site layer termination. Studies of YBCO film deposition have shown that A-site
layer termination prevents the segregation of deleterious copper precipitates,
and thus such substrates are highly desirable for HTSC growth. Single crystal
(001) NdGaO3 substrates were thus annealed in air and oxygen, and the resulting
surface morphologies were investigated by atomic force microscopy (AFM). The
optimum annealing conditions for annealing were found to be 1100 °C for 1 hour
in an argon (or other inert gas) atmosphere, although annealing in air yields
acceptable results.
Elaboration on the Hexagonal Grid and Spiral Method for Data Collection via
Pole Figures. ANTHONY RIZZIE (Ball State University, Muncie, IN,
47306) THOMAS WATKINS (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
A pole figure provides
a representation of the distribution of a particular set of atomic planes
for data acquired through diffraction and is used for analyzing crystallographic
texture or preferred orientation. Pole figures are constructed from a collection
of data points, each with a prescribed azimuthal angle (phi) and sample tilt
angle (chi) (as specified by the goniometer) and measured intensity (counts
or counts per
second). Traditionally, the Schulz
method (5°x5° grid) is employed to acquire the necessary data, but this leads
to a high concentration of data points for small chi values, low concentration
for large chi values, and consequently an inefficient use of time. Two alternative
data collection methods, the hexagonal grid and spiral, have been previously
proposed but only tersely documented in terms of both construction and implementation.
The goal, therefore, is to provide a practical description of the mathematics
required to implement the hexagonal and spiral data collection schemes. Applying
the concepts of equal area and stereographic projections and geometry, spreadsheets
were created to formulaically develop hexagonal and spiral grids, which are then
related to angular movements of the goniometer. Using the generated data points,
the hexagonal grid and spiral methods were programmed by “brute force” into the
existing x-ray software and employed to collect data for a sample of aluminum
foil. The resulting (111) pole figures compared favorably to typical rolling
textures for aluminum foil collected with the conventional Schulz method. The
hexagonal grid has been shown to reduce the number of data points and time needed
to complete a pole figure, while providing equal area sampling. The spiral method
was shown to use only a quarter as many data points as the 5° x 5° grid. In the
future, LabVIEW software will be utilized to develop programs for collecting
data using both the hexagonal grid and spiral methods and then convert the data
back to the conventional 5° x 5° grid.
Electrolysis of Saline for pH Control and Oxygen Production. ANNA BESMANN
(University of North Carolina at Asheville, Asheville, NC, 28804) ELI
GREENBAUM (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Diabetic retinopathy is
a disease which causes small, fragile blood vessels to form within the retina
to
compensate for
the normal blood vessels’ inability to bring sufficient oxygen to the eye. These
blood vessels are prone to hemorrhaging in the eye, causing temporary or permanent
blindness. To help stop this problem before the small blood vessels can form,
electrodes can be implanted into the eye to stimulate the production of oxygen
in the vitreous humor. However, this also induces the formation of free chlorine,
which causes the vitreous humor to become more alkaline. In order to keep the
pH at a manageable level, an anode and a cathode can be implanted into the vitreous
humor while a second anode connected to both electrodes by a sidearm can be implanted
behind the ear. Protons will pass back and forth along the sidearm, keeping the
vitreous humor from becoming too acidic or too alkaline. Alternating between
both configurations keeps the pH stable, as the internal electrodes cause a rise
in pH while the sidearm electrode causes a drop in pH. In these experiments,
two electrodes were put into the buffered saline itself and a third electrode
into a glass sidearm filled with saline solution. To counter the problem of excessive
baseline pH shift, a 2 mM solution of phosphate buffered saline (PBS) was used
instead of pure saline. The solution was sparged at 25ml/minute and heated with
a water bath to 37°C to simulate the fluid motion in the vitreous humor and temperature
of the human body. A DC charge of 800 µA was applied to the electrodes to stimulate
the production of oxygen and a change in pH. The internal electrodes were used
in three minute increments until the pH had moved one pH unit above the baseline,
then the sidearm electrode was used in 1.5 minute increments to bring the pH
down 2 units. Afterward, the internal electrodes were used to bring the pH back
to the baseline. However, the exact amount of time needed to reach the acceptable
limits of high and low pH was variable, and on occasion use of the internal electrode
after using the sidearm electrode for a long period of time caused the pH to
drop for unknown reasons. The next step of this process would be to repeat the
experiment with a solution that is more like the vitreous humor of the eye, and
eventually move on to implanting
the electrodes within an actual eye.
Elevated atmospheric [CO2] concentrations
do not alter net nitrogen mineralization rates in a [CO2] enriched
sweetgum forest. CAITLIN
GUTHRIE (Pomona College, Claremont, CA, 91711) AIMEE T. CLASSEN (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
Carbon dioxide concentrations
([CO2])
in the atmosphere have increased by 36% in the last 250 years. Previous research
has demonstrated that elevated levels of atmospheric [CO2]
can increase plant production. However, to maintain an increased level of growth,
trees must acquire higher levels of soil nutrients. Thus, nutrient availability
might ultimately constrain
the response of forests to elevated [CO2].
In particular, nitrogen (N) often limits plant production in terrestrial ecosystems,
and understanding
how soil N cycling responds to elevated [CO2]
in forests will enable scientists to make better predictions of how forests will
respond to climatic changes in the future. I took advantage of a long-term experiment
at Oak Ridge
National Laboratory (ORNL) manipulating atmospheric [CO2]
to test the prediction
that elevated [CO2] would decrease net N mineralization. Net N mineralization is
the amount of N that microbes have transformed from an organic form to an inorganic
form that is available to plants (minus the N taken up for use in microbial biosynthesis).
The ORNL, Free-Air [CO2] Enrichment (FACE) facility was constructed on a sweetgum plantation
planted in 1988. There are five 25-m rings (two elevated rings where the target
concentration is 550 ppm CO2, and three ambient rings) and the treatments have been running
since 1998. I inserted N mineralization soil cores into each of the rings in
June and July, 2007, and let them incubate for 30 days each. Results indicate
that there is no difference in net N mineralization rates, net N nitrification
rates, or leaching between elevated and ambient plots. However, there was a significant
decrease in net N mineralization rates for both treatments from June to July.
These results may indicate that increased forest production under elevated [CO2] has not altered the net amount of N available for tree uptake
at ORNL FACE. Alternatively, the lack of response to elevated [CO2],
and concurrent temporal response could reflect the low levels of precipitation
(the third lowest on record since 1895) observed over the course of this study.
More work is needed to illuminate
the effects of elevated [CO2]
on soil N cycling and
its effects on forest production at this site.
Energy, Carbon and Climate: Projections to 2025. ALISON
ERLENBACH (University of Florida, Gainesville, FL, 32601) T.J. BLASING
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Energy demands and associated
carbon emissions in the U.S. are expected to increase in the foreseeable future.
Policies to reduce fossil-fuel consumption and carbon emissions must consider
present and future energy needs, and fuels available to most economically meet
those needs, both of which show appreciable inter-regional differences. The National
Energy Modeling System (NEMS), a product of the Energy Information Administration
of the U.S. Department of Energy, projects this growth based on various economic
factors for the country as a whole, and within each of the nine census divisions
of the country. In this study, we summarized output from the NEMS for each census
division, including projected regional carbon emissions which we calculated based
on NEMS-projected energy statistics. To consider climate-change effects on energy
demand, we used the results of an earlier study in which a Parallel Climate Model-Integrate
BIosphere Simulator (PCM-IBIS) was used to drive the NEMS using different climate
change scenarios. Base-case (no climate change) projections show varying increases
in energy consumption and carbon emissions for each region, as their populations
increase at varying rates. Carbon emissions do not increase proportionately to
energy demands, but instead depend on the fuel types each region uses, and is
projected to use, as well as the proportion of energy supplied by electricity.
Electric generation is inherently an inefficient use of thermal energy; only
about one third of the thermal energy produced can be converted to electricity.
The remainder is identified as "electricity-related
loss" in the NEMS. Approximately 20% of U.S. carbon dioxide emissions result
from this "lost" thermal energy. Effects of simulated climate warming,
compared to the base case, were to decrease national energy demand. However,
projected carbon emissions increased because reduced carbon from heating was
outweighed by the increase in carbon emissions for electricity used for cooling.
Regional carbon emissions increased at varying rates, being heavily dependent
on the fraction of energy that is electricity and on the fuel types used to generate
electricity. Policies to mitigate carbon emissions should consider regional differences
in projected demands and in economically available fuels, as well as differences
in regional potentials of renewable energy sources and of technologies that reduce
wasted thermal energy.
Enhancing Network Security by a Centralized and Standardized Dynamic Event
Log Data Collection Method. MARK SEAL (Walters State
Community College, Morristown, TN, 37813) DON WILLIAMS (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
Event logs are at the core
of network security. Without the tracking and logging ability that event logs
allow, there
would be no accountability of the security of the network. The logs allow the
detection of worms and viruses via monitoring system resources and processes,
detection of port scans by monitoring the dropped port requests by the firewall,
detection of brute force password cracking by the number of failed login events,
and the ability to start a trace on the agent when a security event is recorded.
It is imperative that the logs from each machine are parsed and the relevant
information passed on to a central log server (syslog) where the information
can be analyzed and trend analysis preformed. The problem faced is that Windows
does not have a single log that collects all of the required data; instead the
data must be collected in segments. In addition, both XP and Vista are both being
used as operating systems. Each of these OS’s has different ways of storing the
logs, requiring different data collection methods. XP uses evt format as the
logging method while Vista uses an evtx format. XP logs may be ported to the
syslog server while Vista requires that either an event viewer or a data collection
program (e.g. LogParser) be used. The development of the new Windows event log
data collection protocol centers around three core concepts: scalability, control,
uniformity. The chosen method of collection of data by using Powershell scripts
meets all three core concepts. Powershell may be installed on both XP and Vista
machines, while coming mounted on the upcoming Window Server 2008. Scripting
in Powershell allows for the full control of the event log data. The data can
be parsed by content as well as being stripped of superfluous data for storage
and trending in the syslog server. In addition, the data will be supplied to
the syslog in real-time, allowing for real-time trend analysis and alerting protocols.
Powershell scripting also creates a uniform event log data collection protocol
as that Linux system logs are parsed by scripts. Powershell, which is based on
the Korn Shell model, will be easier for cyber security to modify and maintain
the core scripting code. This project will increase the security of the network
by allowing for data collection of the system logs of Windows machines while
decreasing the response time of the cyber-security team by allowing for real-time
data comparison between Linux and Window machines.
Evaluation of Technologies for Protected Asset Management. BEN PETERS
(Maryville College, Maryville, TN, 37830) CHRIS A. PICKETT (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
Protected asset management
is a valuable concept that incorporates rigorous accountability and various
layers of security. Both of these aspects are necessary to create a robust
protected asset management system (PAMS). Radio frequency identification (RFID)
tags were tested for basic accountability purposes, and seals were tested for
asset security. The RFID tag system tested for accountability was based on
an IEEE standard called RuBee. The RuBee system uses a low frequency RF-tag,
antenna, and reader to aid in locating and tracking assets. Multiple RuBee
antenna designs and sizes were tested to determine the best configuration for
monitoring assets in a room. The best design appeared to be a single-loop antenna
that consisted of three connected coils. To test this configuration tags were
placed in the
antenna’s field to check whether the tag was seen in various positions throughout
the room. Preliminary results indicate that this antenna design adequately detects
tags throughout the entire area and could possibly be used in the future as a
piece of an effective PAMS. The security aspect of a PAMS was tested using Russian
rope seals. This seal consists of a seal body, metal connecting rope, and a plastic
optical insert that possesses a serial number that is read and stored by an automatic
seal identifier. A test group of ten seals was used to determine the ease of
use, time for set-up, and overall performance of the seals. These seals were
first assembled and attached to a metal storage drum. They were then stored in
the automatic seal identifier’s memory and checked three times daily. Some design
issues with the seal body and plastic optical insert need to be resolved before
the seals are actually used in the field. More testing needs to be conducted
in order to develop more specific recommendations for the improvement of both
systems and to determine their possible uses in protected asset management.
Event Based NeXus Files. WESLEY KENDALL (University
of Tennessee, Knoxville, TN, 37849) PETER PETERSON (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
When gathering data from
instruments across different locations, a universal file format for representing
the data
becomes essential. The NeXus format is a standard for representing raw data.
My project involves writing a program to convert neutron event files to the standard
NeXus format. The main resource to write this software is the NeXus Application
Programming Interface (API). The API includes many functions for reading and
writing data in the NeXus format. Currently, raw binary neutron event data is
automatically converted into histogrammed NeXus files. This locks the scientist
into a particular choice of histogramming parameters for the data. If the scientist
wishes to perform a histogram parameter data analysis scan to find the optimal
settings, a new histogram file for each parameter set needs to be generated before
data analysis can proceed. An event NeXus file will allow a single file to become
the source for each set in the parameter data analysis scan. Space will be significantly
reduced since the original raw binary neutron data and its associated metadata
will be duplicated in the event NeXus files. My program converts the raw binary
neutron event data into event based NeXus files enabling the previously described
flexibility. The following details further illustrate how my program operates.
First, it reads in a neutron event file, which consists of pixel identification
(id) numbers and pixel time of flight values. Since some detectors have different
electrical set ups, the pixel id numbers will often have to be mapped to other
numbers to closer match the physical detector layout. After the pixel id numbers
are mapped to the appropriate number, the program then reads in a pulse id file.
The file gives the exact starting times of a pulse. Adding the time of flight
value of a pixel id with the corresponding pulse time gives the exact clock time
of the neutron event in nanoseconds. This allows for analysis of different time
slices of data. After all the steps are completed, the event based NeXus file
is created. The data can then be analyzed by scientific software that is specifically
made to handle the NeXus format,
making analysis much more efficient.
Flocking-based Document Clustering on the Graphics Processing Unit. JESSE ST.CHARLES (University of Tennessee at Chattanooga,
Chattanooga, TN, 37415) XIAOHUI CUI (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Analyzing and grouping documents
by content is a complex problem. One explored method of solving this problem
borrows
from nature, imitating the flocking behavior of birds. Each bird represents a
single document and flies toward other documents that are similar to it. One
limitation of this method of document clustering is its complexity O(n2). As
the number of documents grows, it becomes increasingly difficult to receive results
in a reasonable amount of time. However, flocking behavior, along with most naturally
inspired algorithms such as ant colony optimization and particle swarm optimization,
are highly parallel and have found increased performance on expensive cluster
computers. In the last few years, the graphics processing unit (GPU) has received
attention for its ability to solve highly-parallel and semi-parallel problems
much faster than the traditional sequential processor. Some applications see
a huge increase in performance on this new platform. The cost of these high-performance
devices is also marginal when compared with the price of cluster machines. In
this paper, we have conducted research to exploit this architecture and apply
its strengths to the document flocking problem. Our results highlight the potential
benefit the GPU brings to all naturally inspired algorithms. Using the CUDA platform
from NIVIDA®, we developed a document flocking implementation to be run on the
NIVIDA® GEFORCE 8800. Additionally, we developed a similar but sequential implementation
of the same algorithm to be run on a desktop CPU. We tested the performance of
each on groups of news articles ranging in size from 200 to 3000 documents. The
results of these tests were very significant. Performance gains ranged from three
to nearly five times improvement of the GPU over the CPU implementation. This
dramatic improvement in runtime makes the GPU a potentially revolutionary platform
for document clustering algorithms.
Heat-Reflective Paint for Deck Surfaces of Naval Vessels. EMILY
OTTENWELLER (University of St. Francis, Fort Wayne, IN, 46808) RICK
LOWDEN (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The new V-22 Osprey aircraft
has the capability to vertically take off from and land on the deck of an
aircraft carrier. During take off and landing, the hot exhaust from the Osprey
aircraft engines impinges directly onto the deck of the ship. The deck surfaces
were not designed to handle high temperatures and thus warp from the excess
heat. Insulating paints that use special ceramic additives have been developed
to improve the energy efficiency of buildings and structures. The decks of
naval vessels are coated with paints that include ceramic grit to make them
non-skid. It was hypothesized that the insulating additives could be used
to replace the non-skid grit and create a paint that could protect the deck
from the hot exhaust. Ceramic particles were added to an epoxy-based surface
coating to alter the layer’s thermal properties, i.e. to reflect, absorb
or conduct heat. The ceramic additives include Bionic Bubbles which are hollow
microspheres derived from fly ash, Insuladd particles which are hollow ceramic
mircospheres invented by NASA, and silicon carbide platelets. The test specimens
were ˝ inch thick steel plates to which paints with different additives were
applied. The plates were heated using a heat gun to simulate the exhaust
of the aircraft and temperature distributions on the backside of the painted
specimens were measured. The temperature distributions for the plates coated
using paints with additives were compared to results for bare metal, paint
with no additive, and the standard non-skid deck coating. The plate with
the highest concentration of Bionic Bubbles was the most effective in reducing
the temperature of the plate; however, the layer is likely too fragile for
the application. The deck coating must not only be insulating but also robust
and non-skid. It appears that the ceramic additives will need to be modified
to best suit the needs of this application.
Heavy Truck Duty Cycle Data Collection. FIONA
DUNNE (University of California, Santa Barbara, Santa Barbara, CA,
93106) GARY CAPPS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Real-world data on Class-8
truck operation is necessary for fuel efficiency studies as well as for use
in vehicle powertrain design software. To gather this data, six Class-8 trucks
were instrumented with a data acquisition system (DAS) and a set of sensors
to monitor numerous vehicle performance parameters from engine to tires, as
well as weather conditions, road slope, and load weight over a one year period.
First, the truck's J1939 vehicle network was tested to learn what vehicle performance
information was available on it, and how to retrieve the data of interest.
The other sensors and DAS were then installed on each truck, and all data was
recorded to the DAS as the trucks then continued in regular operation. During
operation, data was checked weekly for errors to determine whether the equipment
was functioning correctly. By checking the data, it was discovered that weather
sensors began failing from water entry due to unexpected pressure washing of
the trucks. Load weight data was found to be inaccurate, as truck drivers had
not correctly calibrated the weighing system. Road slope and vehicle network
data results were as expected. It was concluded that weather sensors should
be covered during pressure washing, and an alternative method for calibrating
the weighing system was devised. It was also concluded that the method used
to obtain road slope, a derivation from GPS vertical and ground velocity data,
was adequate. Finally, it was determined that no changes needed to be made
in the method of communication with the vehicle network. Data will continue
to be checked for errors throughout the remainder of the one year test, and
changes
will be made as necessary.
Hydrodynamics of a Centrifugal Contactor. MEECKRAL
WILLIAMS (Prairie View A&M University, Prairie View, TX, 77446)
DR. COSTAS TSOURIS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Countries producing
nuclear energy have an interest in nuclear fuel reprocessing, a chemical
procedure that extracts fissile materials such as uranium-233, uranium-235,
and plutonium-239 from fission products and other materials in the spent
nuclear reactor fuels. The goal is to recycle materials that are useful
for further nuclear energy production. Centrifugal contactors are used
in many plants for the reprocessing of fissile materials. By the use of
centrifugal force, the contactor has the advantages of intensive mixing,
rapid phase separation, and chemical separation by liquid-liquid extraction
in a single unit operation. Two immiscible fluids of different densities,
usually an aqueous and an organic fluid, are fed into the contactor to
obtain two-phase mixing and extraction. The objective of this work is to
determine flow patterns and dispersion properties, such as drop size distributions,
in a four-inch diameter centrifugal contactor. The two fluids used here
are water and dodecane at flow rate ratios ranging between 1:5 and 5:1.
The total flow rate is on the order of 600 mL/min, and the agitation speed
is up to 3600 rotations per minute. Once the dispersion is formed, a sample
is taken into a light scattering cell where cetyl trimethyl ammonium bromide
(CTAB) solution is initially located. The CTAB is a surfactant that stabilizes
the droplets to prevent coalescence. Results of particle size measurements
obtained by the LS130 light scattering instrument from Coulter have shown
that only small droplets can be measured by this method because large drops
escape fast to the top of the cell due to buoyancy, even though the sample
in the cell is stirred. Video photography using a camera that operates
at fast shutter speed and frame recording was employed to visually observe
the dispersion in the contactor through an optically transparent wall.
Video images reveal details of the drop size, air bubble entrainment, and
flow dynamics of the mixing zone. Video imaging has the advantage of direct
visualization of the droplets; however, the disadvantage is that it is
difficult to distinguish bubbles from droplets. It is hypothesized that,
because the difference in the refractive index is greater for air and water
or dodecane than for water and dodecane, air bubbles appear sharper on
the video images. Drop size measurements are obtained from the images through
a size calibration procedure. The size of
drops ranges between 1µm and 500 µm.
Imaging Diagnostic Systems for the Spallation Neutron Source. KATHLEEN
GOETZ (Middlebury College, Middlebury, VT, 5753) TOM SHEA (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
Since the start of commissioning,
imaging beam diagnostics have been utilized widely at the Spallation Neutron
Source (SNS) as quick intuitive diagnostic measures and for the calibration
of other diagnostic instrumentation. Because other imaging systems such as
the Video Foil Monitor proved indispensable, there was a drive to create
new systems such as the temporary Target Viewscreen (TVS) and the Small Angle
Neutron Scattering (SANS) Neutron Beam Stop Monitor (NBSM). My work on the
TVS was performed over 3 semesters,
with this summer’s focus being on system documentation. Although the temporary
TVS, a system that my mentor and I designed and implemented, has already served
its purpose and has been decommissioned, my work on the project continues in
the form of a paper and presentation at the International Accelerator Applications
conference that was at the end of July 2007. I am also part of a team that is
working on plans for a second generation Target Viewscreen to be implemented
next year. The NBSM is a new project with initial design work to be completed
by the end of August 2007. Earlier this summer, I performed calculations to estimate
the light that will be collected by the second generation TVS and NBSM optics.
Presently, my work on the NBSM includes an as yet to be completed experiment
at HFIR to look into the types of optics required for a successful system. I
am also currently designing the experimental
set up.
Implementing Optimized and Scalable Non-Standard Matrix-Multiply Algorithms. RANDY HASSELL JR. (Old Dominion University, Norfolk,
VA, 23455) RICHARD BARRETT (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Matrix-Multiplication is
the fundamental operation for solving several algorithms including other linear
algebra operations like matrix inversion, systems of linear equations, and
matrix determinants.
It’s also used in computer graphics and digital signal processing. The Computational
Materials Science Group at the Oak Ridge National Laboratory (ORNL) is developing
a large-scale computer application that studies the fundamental properties of
materials. The performance of this materials science code relies heavily upon
the execution of matrix-multiplication. The dimension of the matrices are 32
x N, where N is currently 4K, and continues to expand to 40K. The purpose of
this project is to create an optimal algorithm that performs matrix-multiplication,
and to research the implementation on different computer architectures. Using
the Fortran language, all the matrices are dynamically allocated, so that memory
is created and destroyed without wasting any. Then, double precision random numbers
fill both matrices. There are three multiplication techniques to test, a Fortran
function matmul, a source file dgemm.f, and the subroutine dgemm directly from
lblas during compilation. The timer used is a subroutine called gettimeofday()
in the C language. The algorithm calculates the Floating Point Operations per
second (FLOPS) that measure an algorithm’s performance on a processor. For multiplying
rectangular matrices, I am testing from 5x5 to 40Kx40K using iterations and 10
trials each. For multiplying square matrices, I am testing from 5x5 to 4Kx4K.
I am compiling my algorithm with these computer processors: Intel Celeron, Pentium
4, and the Cray XD1(dmz00 & wc00). For matmul, the performance dropped as
the size grew from an average of 5GFLOPS to 1 MFLOP on all processors. For dgemm.f,
the dmz00 performed the best leveling around 225 MFLOPS as the size increased.
For square matrices, the performance dropped as the size grew on all processors,
and that is due to the increased amount of time it takes to multiply square matrices
because after all, a 1Kx32 takes less time to read than a 1Kx1K. Overall, the
best performance came from the wc00 using dgemm, where the performance leveled
at 600 MFLOPS for the larger matrices. The implementation of the algorithm will
continue on the hardware side by taking into account the layout of the memory
and the transport speed from the main memory to the local cache, and then the
materials code should run optimally.
Improving Power Density of a Microbial Fuel Cell by Optimizing Electrode Area
and Substrate Delivery. SCOTT
CESAR (Western Michigan University, Kalamazoo, Michigan, 49007) ABHIJEET
BOROLE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Microbial Fuel Cells (MFC’s)
are devices which use micro-organisms as catalysts to oxidize compounds such
as lactate whereby electrons are released and are allowed to flow between electrodes
to generate current. The box-type MFC involved used Shewanella oneidensis in
a minimal media with lactate and a carbon felt electrode as the anode. An air
cathode was used involving a platinum/carbon electrode. Improving the power density
output of an air cathode MFC was the primary goal if this work. The MFC performance
can be assessed by analyzing the electrical and chemical/biochemical parameters
of the system. The current can be determined by monitoring the voltage across
a fixed load using a voltmeter. The electrical performance of the MFC can be
determined by first measuring the open circuit voltage (OCV) and current produced
across a variable load resistor. Along with electrical measurements, samples
of the anode solution are taken to determine the changes in biochemical characteristics
of the MFC. Under no-flow conditions, the MFC stabilized at 0.177 volts. With
the introduction of flow to the system, the MFC stabilized at 0.347 volts. The
power density at this time was found to be 128.6 mW/m2 with a current density
of 446.4 mA/m2. Further improvements in power delivery are possible via a more
compact design of the fuel cell and flow of the media across a three-dimensional
electrode.
Improving Roadway Safety by Implementing Wireless Inspection Systems for Tractor
Trailers. RANDALL PLATE (Cedarville University, Cedarville,
OH, 45314) GARY CAPPS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
According to the Federal
Motor Carrier Safety Administration (FMCSA) there were over 144,000 large trucks
involved in fatal and non-fatal crashes in 2005. Their Large Truck Crash Causation
Study revealed that 56 percent of fatal truck crashes are due to truck-driver
error and the majority of vehicle failure-related crashes are due to brake failure.
Safety inspections can help prevent such occurrences by identifying drivers who
have driven too long or trucks that are unsafe. However, with over 8 million
commercial trucks (10,000 lbs. or greater) on U.S. roads today, officials are
limited by the lengthy manual inspection process to performing only about 3 million
safety inspections per year and see a violation rate of approximately 72 percent.
It is estimated that an electronic device that could collect vehicle and driver
information electronically and wirelessly transmit this inspection data to the
roadside could greatly expedite the inspection process, thereby increasing the
number of safety inspections carried out each year to approximately that of weight
inspections: about 82 million. The present project is the first of three phases
of Oak Ridge National Laboratory’s Wireless Roadside Inspection program. It will
begin examination of the technical and legal issues surrounding the implementation
of a Universal Wireless Inspection System (UWIS), assemble prototype technology,
test the functionality of this equipment, and report on the feasibility of implementing
such a device in commercial vehicles. This UWIS will be capable of accepting
driver input for identification purposes and hours of service recording, as well
as information from the vehicle’s onboard data bus (J-1708 and/or J-1939) to
monitor vehicle status. It will then format this information and transmit it
to either the roadside or a patrol car via a pair of wireless transceivers. Software
that will be used at the receiving end to collect the data from the transceiver
and display it for inspection officials
is also currently being developed. FMCSA’s Federal Motor Carrier Safety Regulations
as well as information gathered from the Tennessee Department of Transportation
will guide the development of this technology by providing data set content and
operational requirements. Proof of concept testing is scheduled to begin in June
of 2007, with a full field operational test to follow in 2008.
Improving the Documentation of Findings and Corrections. PHILIP
IRMINGER (Pellissippi State Technical Community College, Knoxville, TN,
37933) JOHN CZACHOWSKI (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Currently at ORNL, there
is a program in place known as the Operational Awareness Program (OAP). This
program is designed to help ensure that regulations are being followed in the
various laboratory spaces, and that proper safety measures are being addressed
to help protect all those involved. The OAP team has members consisting of Subject
Matter Experts
(SME), and also DOE representatives. Using
a variety of SME’s allows for a vast variety of knowledge of the various hazards
which may be present including chemical, electrical, and environmental. During
the OAP inspection, findings are found and documented including violations, possible
hazards, and also noteworthy practices. In the past, documenting these findings
has been documented via confirmation in writing; however I have been tasked with
assisting in documentation of these findings via photographs. I will assemble
pictures of the findings both before and after corrective actions have taken
place. Through assembling these photographs the corrective actions that have
taken place will be relayed to the OAP team to document resolution of the findings.
By following this procedure, there is no doubt about the corrective actions that
have been completed. It also allows for reference photographs for similar issues
in other sections of the laboratory. Through the use of this documentation of
the OAP assessments, there will be a reliable and effective way of documenting
the corrective actions which have taken place to resolve any issues found during
the inspection.
In Situ Measurement of Stresses in Carburized Gears via Neutron Diffraction. JEFFREY BUNN and BRYAN BOGGS (University of Tennessee
at Martin, Martin, TN, 38238) CAMDEN HUBBARD (Oak Ridge National Laboratory,
Oak
Ridge,
TN, 37831)
Carburized gears are characterized
by a very hard outer layer that contains chemistry, phase, and microstructure
gradients. X-rays have been used in the past to attain measurements of residual
stresses, but X-ray diffraction is limited to near surface stress measurements
due to attenuation. X-ray diffraction also has difficulty reaching the critical
stress regions of a gear tooth due to beam interference from the complex geometry.
This research seeks to develop experimental methods for measuring the stresses/strains
in carburized gears at locations unattainable by X-rays and to do this as a function
of applied load on the gear tooth. Experiments are being performed to determine
if neutron diffraction can be used as an alternative to X-ray diffraction to
measure the total stresses. Total stresses consist of both the residual stresses
imparted during the carburization process and the load induced stresses resulting
from power transmission. The experiments are being performed at the Neutron Residual
Stress mapping Facility (NRSF2) at the High Flux Isotope Reactor (HFIR). In neutron
diffraction, a powder sample is normally used to determine the unstressed lattice
spacing or d0.
In carburized components,
d0 can
not be determined from a single powdered sample because of the non-homogeneous
material in the carburized region. As an alternative to using a powder sample,
a method
commonly used in X-ray diffraction known as the sin2
method is being studied to determine if it can be used with neutron diffraction
to accurately quantify
d0 in
the carburized
region. If successful, the sin2 method will be used to determine d0 at a number of points in the carburized region. Neutron diffraction
methods will then be used to measure the d-space at each of the points for which
d0 was determined. The combination of d-space and d0 at
each point will enable the strains and stresses to be determined at the measurement
points. The measurement of the d-space in a loaded gear is being facilitated
with a Static Load Application Device (SLAD). This device was designed to statically
load the gears as well as be compatible with the equipment at NRSF2. Stress analysis
was done on the SLAD to ensure that the device would not exceed strength values
found in engineering
design standards.
Investigate How Different Operating Conditions or Different Reactors Produce
Different Fission Product Nuclides, Using ORIGEN Code. DAVID
ASKINS (Kansas State University, Manhattan, KS, 66506) CHARLES WEBER
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
There are many questions
in today’s age when it comes to the problem of radioactive nuclear waste. With
the several different types of engineered nuclear reactors in existence around
the world, there are many varied output nuclides that are generated as a result
of the broad range of running conditions in certain types of reactors. To determine
the theoretical output nuclides ORIGEN/ARP code was used. It is a sequence
in SCALE that serves as a fast and user-friendly method of performing nuclear
irradiation and decay calculations, using problem-dependent cross sections.
All possible reactor types were ran with different variables, such as burnup,
average power, fuel assembly, enrichment of fuel, percentage of time the reactor
was powered up, and the amount of cycles. Once the variables were plugged in,
the nuclide output products were taken and compared to those of the same type
of reactor under different conditions, and to those of different reactors under
different situations and similar circumstances. They were evaluated by first
finding the average amount of a nuclide for a single reactor, and then measured
up to different reactors by finding either the percent difference between the
two nuclides, or the ratio between them. Each reactor type was compared to
each of the other reactor types. Following this, the main differences were
identified to recognize trends, if any, in the various output products related
to the varying reactors. To accomplish this task, for each reactor, several
different cases were run, keeping the burnup value the same, while varying
the average power and running period. Following the running of each specific
case, an executable file, 71process, was created to output all possible fission-product
nuclides and their respective weights in gram-atoms. These results were then
used to generate Excel spreadsheets with the ratios of how many parts of a
given element are produced by one reactor, as compared to another. These ratios
were then analyzed for certain trends of nuclides between reactors. At this
time no results have been obtained. With nuclear power becoming ever more present
in
today’s power industry, we are inevitably faced with the problem of spent fuel
accumulating. Furthermore, with the ever-present threat of nuclear waste falling
into the wrong hands, it is essential to be able to identify where nuclear waste
came from. To achieve tangible
results, more research should be conducted.
Leak Detection Device. ELISABETH BYRD (Georgia Institute
of Technology, Atlanta, Georgia, 30332) DAVE LOUSTEAU (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
When mercury is sensed between
the mercury vessel and water shroud in the Spallation Neutron Source target,
a leak exists and the target has to be removed from operation. To improve future
targets, the front of the target is examined to determine the cause and location
of the leak. Most likely, a leak will be visible, but if not, a leak detection
device needs to be available. My work was to model and design a leak detection
device that would enable the inside of the target to be pressurized while coated
with a chemical that will bubble when the air seeps through the cracks, revealing
the location of the leak. I was first given an assembly that included a table
with a simulated flange serving as the top, which would hold the target. The
assembly also included a lid that is placed on the top of the target to seal
it. The entire leak detection device will be radioactive after use; therefore,
one goal is to minimize the amount of material when designing the assembly. There
is a boot already in the hot cell, which was made to provide shielding for the
front end of the target when it is being removed. I used this boot instead of
the table so that no waste would be created and nothing new would have to be
designed or manufactured with the exception of a part connecting the flange to
the boot. This new part was designed to accommodate the racetrack shape on the
top of the boot and the circular shape of the flange. The initial adapting part
model used a blend from the racetrack shape to the circular top. Unfortunately,
this direct approach would be both difficult and expensive to manufacture. I
then modeled a more manufacturing friendly part using the racetrack shape as
the dominant feature and then attached wings on the top to accommodate the circular
flange. This way, the manufacturer could use sheet metal to form the racetrack
shape and then weld a piece of sheet metal to the top, which would form the wings.
The stress on the part was calculated using the finite element analysis tool,
Mechanica. Mechanica indicated that it can withstand loads much greater than
the 900 pound force that will be applied from the weight of the target and seal
assembly. In addition to learning a new modeling program, this challenge taught
me to include from the outset design concerns for manufacturing, robot assembly,
and end waste management.
Linking Microbial Diversity and Geochemistry of Uranium-Contaminated Groundwater. DANIELLE HALL (University of Michigan-Dearborn, Dearborn,
MI, 48128) CHRISTOPHER SCHADT (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Microbes control many
of the important geochemical processes that occur in the environment. They
utilize and produce nutrients that are involved in eutrophication and are
even capable of cleansing the environment by degrading a vast variety of
chemical compounds. In this study, microbial communities were assessed based
on clone libraries of 16S rDNA genes from the Department of Energy Field
Research Center. The samples were collected from four different sites (GW-835,
GW-836, FW-113-47, and FW-215-49) containing varying levels of pH (3 to 7),
nitrate (44
to 23,400 mg/l-1) and uranium (0.73 to 60.36 mg/l-1). Community DNA was extracted by grinding the samples with sterile
sand and liquid nitrogen. The resulting DNA was purified then amplified using
polymerase chain reaction (PCR) with 16S ribosomal primers. The 16S ribosomal
genes were cloned using a PCR 2.1 vector and then transformed in E.
coli cells.
The clones were then screened by PCR and sequenced. The sequence data were analyzed
for each clone library using BioEdit, DOTUR, LIBSHUFF, and RDP Classifier. Results
indicated that bacterial diversity correlated with the geochemistry of groundwater.
Bacterial diversity was highest at the site with a neutral pH and containing
the lowest concentrations of nitrate and uranium (GW-836). The diversity decreased
with declining pH values and increasing concentrations of nitrate and uranium.
This difference reflects not only the diversity measurements and indices of nucleotide
sequences but also LIBSHUFF analysis of clone libraries. The clones consisted
primarily of sequences closely
related to the phylum Proteobacteria, with site FW-113-47 almost exclusively containing this phylum. Firmicutes, Bacteroidetes,
and Chloroflexi were
also very prevalent bacterial groups in all samples except FW-113-47. The microbial
community information gained from this study and previous studies at the site
can be used to develop predictive multivariate and Geographical Information System
(GIS) based models for microbial populations at the FRC. This will allow for
better understanding of what organisms are likely to occur where and when based
on geochemistry, and
how these relate to bioremediation processes at the site.
OSCAR Diskless. WILLIAM ADERHOLDT (Tennessee Technological University,
Cookeville, TN, 38505) STEPHEN L. SCOTT (Oak Ridge National Laboratory,
Oak Ridge, TN, 37831)
OSCAR, Open Source Cluster Application
Resources, is software used to create and manage high performance computing clusters.
The current method of installation assumes that each compute node is equipped
with a local hard disk. However, the trend in high performance computing today
is leaning towards diskless clusters where compute nodes do not require local
hard disks. The motivation for diskless clusters include reduced power, lower
hardware costs, and improved reliability (hard disks are notoriously prone to
failure). This work extends OSCAR to support the creation and management of both
diskfull and diskless clusters. In order to enable diskless OSCAR nodes, a boot
method known as NFS-Root is used. This means that during the bootstrap phase
the compute nodes will mount their root partition via a Network File System (NFS)
share, eliminating the local hard disk requirement. The way this is done, specifically,
with OSCAR is to mount a small root partition containing only what is absolutely
needed for the init process as read/write. All other directories are mounted
as read-only from a NFS shared network folder, which is accessed by the diskless
nodes in the cluster. Init is modified in order to obtain a diskless node by
mounting the network shares before any other work is done. So, through creation
of a NFS shared network folder, a small root partition, and modification of the
init process, OSCAR is able to create and maintain both diskfull and diskless
clusters. This ability aligns OSCAR with the current trends in high performance
computing and creates more efficient clusters as it reduces power, lowers hardware
costs, and increases
reliability.
Patterning a PDMS Scaffold Towards Wound Healing. TEJAS
DOSHI (Wofford College, Spartanburg, SC, 29303) BARBARA BECKERMAN,
APRIL MCMILLAN, BOYD EVANS (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
One of the most important
functions of skin is to act as a barrier against pathogens. This function is
compromised when a person suffers a partial-thickness or full-thickness wound.
The wound triggers a healing cascade that consists of three phases: inflammation,
proliferation, and tissue remodeling. The rate of wound healing determines
if scars form and how quickly skin can regain its purpose to serve as a barrier.
Depending on the severity of the wound, the healing process may last from a
few days to several months or longer. During the last thirty years, there has
been much interest and research in applying micro and nano-scaled technologies
to increase the rate of wound healing. These technologies include patterning
and functionalization of implantable materials. Patterning involves changing
the surface topography of a substrate. Functionalization involves attaching
different functional groups or signaling proteins to a substrate. The purpose
of this research is to determine a method to increase the rate of wound healing
using these micro and nano-scaled technologies. Extensive literature searches
were conducted to determine appropriate methods for patterning and functionalizing
a scaffold. Polydimethylsiloxane (PDMS) was chosen as the scaffold for the
experiments because it has been shown to be biocompatible with the human body.
Self-assembled polystyrene-block-polyacrylic acid (PS-b-PAA) diblock copolymer
micelles act as the template for patterning PDMS. The goal was to achieve regular,
evenly spaced patterns. However, the micelles formed bifurcated striations
which did not allow patterning of PDMS. This result is attributed to using
PS-b-PAA with a higher molecular mass than described in previous literature.
A close substitute was used because the vendor no longer sells the PS-b-PAA
described in the referenced experiment. Assuming that the micelles form regular,
evenly spaced patterns in future experiments, dermal fibroblasts will be seeded
onto molded scaffolds to determine if a patterned surface can best be used
to increase proliferation of skin cells so as to also increase the rate of
wound healing. Cell proliferation will be measured via a Coulter Counter device.
The substrate will also be functionalized with different signaling proteins
to induce a greater rate of wound healing. These experiments are the initial
stage of a long-term goal to create a therapeutic material that will increase
the rate of wound healing.
PDF Forensics and Steganography Detection. BRANDON
LANGLEY (University of Tennessee, Knoxville, TN, 37996) MIKE NEERGAARD
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Portable Document Format
(PDF)
is used to display two-dimensional documents in a device-independent manner.
Standard PDF viewer applications, such as Adobe Acrobat, are designed to hide
more information about PDF files than they display. A PDF file consists of a
series of objects that are referenced whenever they are used. There are various
methods of hiding content inside a PDF file so that a viewer will not display
it. This makes PDF an ideal format for hiding information, because most people
will view the file in a standard viewer and will not dig deeper into the structure
of the file. The science of hiding this information so that only certain people
know there is anything hidden is known as steganography. There is no reason for
a person to go out of their way to dig into a stegonagraphic document, because
nothing appears hidden to the normal eye. I am researching the different ways
to hide content inside a PDF file and, in turn, the different methods of extracting
hidden data from a PDF file. I am also writing a standard C++ Linux application
package to aid in the extraction of any hidden data present in the file. Currently,
there is no application designed to help with PDF forensics in this manner. I
am using the Adobe PDF Reference (second edition) to study the complete PDF specifications,
and the Poppler general public license library to help with the PDF parsing.
The application first prints all metadata from the file that may be useful for
a forensics investigation. This includes the author, application used to create
the file, creation date, modification date, etc. In addition, this application
searches for and displays any content that is hidden in the file and not viewable
in a standard PDF viewer. This is a three phase process. First, the application
finds every legal object that is in the file but never referenced by a page.
Second, it searches for any content that is hidden between legal objects. Finally,
the application looks at the instructions for displaying each page. If an object
is referenced by a page, but never used
in the page’s actual display instructions, those objects are also considered
hidden. Any hidden content is then displayed for the user. This application should
aid in investigations involving computer crimes such as child pornography. If
someone has criminal content hidden in a PDF file so that only they know how
to view it, this application should help to expose it.
Penetration Testing of ORNLGOV. TRISTAN
BITHELL (University of North Carolina at Charlotte, Charlotte, NC, 28078)
DON WILLIAMS (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Today, the risk of an internet
based attack is greater than ever. Google.com has become the target of hackers
to be
used as a tool for reconnaissance. Google is capable of revealing vulnerabilities
in web sites if you know the proper search operators. Through the use of a Google
API (Application Programming Interface) key one can even automate the reconnaissance
process. Other tools such as spider crawlers and backend tools can also reveal
vulnerable files or URL’s that should have remained hidden. Also, the listing
of excessive contact data can be used in a social engineering based attack. My
project was to use manual searching and automated tools to attempt to locate
any vulnerabilities or unprotected, sensitive data on onrl.gov or any leaked
information from the lab to a newsgroup. I used Athena 2.0, Wikto, Paros, SiteDigger
2.0, and Aura in my project. During my initial setup, I found that Google no
longer issues API keys so I was able
to use SnakeOil Lab’s Aura program to simulate an API key. I used Athena 2.0,
Wikto, and Site Digger 2.0 to look for common vulnerabilities that were listed
in the Google Hack Data Base at johnny.ihackstuff.com. Wikto is a multipurpose
tool that I used for several tests. First I scanned the website for known vulnerable
directories. Next I scanned those directories for known vulnerable files. Wikto
would use an AI to assess if a URL or file existed but this tended to often return
false positives and lead to URL’s that did not exist. With Paros I set up my
browser to redirect traffic through a local proxy server run by Paros to intercept
and modify data packets. As I browsed ornl.gov, Paros would save the URL’s that
I visited. I then activated a spider scan on a URL to generate a list of every
directory and file in the website. Though ornl.gov itself proved too massive
to scan in its entirety, I was able to complete a scan of neutrons.ornl.gov which
is the website for the SNS facility. Through my penetration testing, I was able
to extract various pieces of possibly sensitive information. From the results
of the tests and measures taken to secure ornl.gov’s data, the website will be
more secure against the threat of an attack.
Performance-Based Brake Testing: A Quantitative Analysis of Break Wear within
the Trucking Industry. AMANDA BLAGG (Pensacola Christian
College, Pensacola, FL, 32523) GARY CAPPS (Oak Ridge National Laboratory,
Oak Ridge, TN, 37831)
Little is known about
the brake performance of commercial motor vehicles within the United States
since the current method of inspection is visual and subjective. However,
brake life and wear are of great interest to the transportation community,
because faulty brakes are both a primary cause of collisions in the trucking
industry and a significant expense to trucking companies. In order to assess
brake performance, aftermarket brake drums and shoes will be supplied to
four industry partners who maintain fleets of class-8 vehicles. Tankers,
dry-box vans, dump trucks, and motor coaches will be tested to provide data
for each category of heavy vehicles. Each vehicle will be tested on a performance-based
brake tester (PBBT) which has been installed at the Greene County Inspection
Station on I-81 in Tennessee. Testing will take place at regular intervals
varying from weekly to monthly and will continue over the brake life, which
may range anywhere from
8 to 18 months. The PBBT’s in-ground roller dynamometers will objectively evaluate
braking force of each wheel end. Since this braking force is proportional to
vehicle weight, artificial axle loading will provide 80% of the gross axle weight
rating through hydraulically-operated hooks. As brake force is also dependent
upon air pressure, transducers will be used to measure air pressure available
in the brake line. To determine wear over brake life, the thickness of brake
pads will also be measured with a caliper and the ovality and eccentricity of
brake drums will be measured with a digital indicator before and after the testing
period. I wrote the test plan for the experiment, researched equipment used to
make initial measurements of eccentricity, and conducted initial tests on the
PBBT. The results from this experiment will provide a previously unavailable
performance curve for brakes across several industries and will lay groundwork
for future studies in which the PBBT may be utilized as a diagnostic tool for
faulty brakes.
Phosphate Enhanced Uranium Reduction. RACHEL
FAIRBANK (Tompkins Cortland Community College, Dryden, NY, 13053) ANTHONY
V. PALUMBO (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
A common contaminant found
at DOE sites is uranium, which characteristically leaches into groundwater
and surrounding soils. Remediation of these sites is therefore a DOE focus.
Current technologies mainly consist of pump and treat technologies which have
the disadvantage of being invasive and ineffective in areas with low flow velocity.
Total cleanup costs using existing technologies are estimated to exceed a total
of $220 billion, making it worthwhile to investigate alternative methods of
uranium remediation. One focus for remediation is the stabilization of uranium
through reduction of mobile U(VI) to its less soluble and immobile form U(IV).
One possibility is by stimulating existing microbial communities to reduce
uranium. Previous experiments
had demonstrated the ability
of electron donors’ ethanol and methanol to stimulate bioreduction of uranium.
This experiment investigated the idea of phosphate being a limiting nutrient
in bioreduction of uranium. Anaerobic microcosms were created using contaminated
soil from the Oak Ridge Field Research Center. Samples were analyzed at specific
time points throughout the experiment using a Kinetic Phosphorescence Analyzer
which measured the amount of soluble uranium. This experiment found that the
addition of phosphates led to immediate removal of uranium from solution. This
effect was observed to be independent of the presence of an electron donor, as
a similar effect was observed in the microcosms with only phosphates added. Therefore,
these results imply that reduction is due to a chemical interaction with the
phosphates rather than due to stimulation of the microbial community.
Photoelectrochemically Splitting Water Using TiO2 Nanotubes. LATOYA
HARRISON (Prairie View A&M University, Prairie View, TX, 77446)
DR. COSTAS TSOURIS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Fossil fuels, burned
for
energy, are
polluting the earth’s ecosystem. Hydrogen is a non-polluting fuel that could
be used, instead of fossil fuels. The question is how one can efficiently produce
hydrogen. The purpose of this project is to photoelectrochemically split water
to produce hydrogen. The concept is to use light to split water molecules into
hydrogen at the cathode and oxygen at the anode. The experimental system used
in this study consists of a power source
attached to a titania (TiO2) nanotubes anode and a platinum cathode. Ultraviolet (UV) light
irradiation of the anode is used to reduce the amount of electrical force required
by the electrolytic process. An aqueous solution containing 1M sulfuric acid
completes the circuit. The specific contribution of this work tests the hypothesis
that a film of TiO2 nanotubes synthesized at Oak Ridge National Laboratory can be
used as a photoactive anode with improved efficiency. This hypothesis is being
tested through a set of experiments using different anodes. We used: amorphous
TiO2,
rutile
crystalline TiO2, and anatase crystalline TiO2 nanotubes. We found that, in all cases, photoillumination of
the anode increases the produced current. The TiO2 anatase crystalline structure produced the highest increased
in photocurrent. Higher produced currents led to higher hydrogen production.
TiO2 anatase
nanostructures showed the highest photo efficiency, about 0.3 percent, of the
total light energy used in the experiments.
Platform for Secure Remote Access to Sensors through an Ethernet Network. NATHAN ROWE (University of Tennessee, Knoxville, TN,
37996) CHRIS PICKETT (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
In Nuclear Material Safeguards,
sensors are frequently used to verify material attributes during processing,
transportation, and storage. The ability to remotely read and configure these
sensors, with confidence in the security and accuracy of the transmission
would significantly reduce the need for on-site inspections. A compact and
secure sensor platform was designed by the student to meet these needs. The
sensor platform measures 56 by 24 by 22mm and provides secure communications,
general purpose I/O ports, a dedicated bus for interfacing with various types
of sensors, and is fully web enabled. The system is powered over Ethernet,
which not only minimizes installation complexity and cost, but also allows
the sensors to be distributed away from customary power sources. Support
for encryption and authentication protocols at the sensor ensure that the
platform is suitable for high security deployments. A compatible Geiger Mueller
radiation detector sensor board was also designed by the student to serve
as a proof of concept demonstration. The design shows promise for use in
many distributed sensor applications. Remaining steps include further testing
of the platform, improved end user software, and further development of compatible
sensor packages, including a potential radio
frequency based design.
Poor litter quality under elevated atmospheric carbon dioxide concentrations
reduces aquatic macroinvertebrate colonization of decomposing leaf
litter in streams. VANESSA GARCIA (California State University, Fresno,
Fresno, CA, 93740) AIMEE T. CLASSEN (Oak Ridge National Laboratory,
Oak Ridge, TN, 37831)
Levels of atmospheric CO2 have
increased since the industrial revolution and are expected to continue to rise.
Previous work has shown that leaf litter produced by trees grown under elevated
levels of atmospheric
CO2 is of lower quality (increased carbon (C) to nitrogen (N) ratios)
relative to leaves grown under ambient CO2 levels. While many studies have focused on how this change in
quality may alter terrestrial decomposition, few have investigated how it may
alter invertebrate decomposition of leaves in streams. Our objective was to determine
whether a decline in leaf litter quality (i.e, an in increase in litter C:N)
due to elevated atmospheric [CO2] would decrease the number of invertebrates that fed on leaf
litter in streams. Leaf litter used in this experiment was collected from the
Oak Ridge National Laboratory (ORNL) Free Air Carbon Enrichment (FACE) site in
early September, 2006 after leaf senescence. Leaf litter from each ring was combined
by treatment (ambient or elevated) and placed into mesh decomposition bags. Bags
were submerged in a first order stream on the Oak Ridge reservation and removed
at five different time periods between January and May 2007. Upon returning to
the laboratory, samples were processed to remove litter invertebrates. Results
indicate that, over time, there are less aquatic invertebrates on leaves grown
under elevated atmospheric [CO2].
These results suggest that stream macroinvertebrates prefer to colonize and feed
on leaf litter of
higher quality (i.e., litter grown under ambient CO2. conditions).
Processing Text Data and Advanced Search Capabilities for the Intelligence
Community. JON DOBSON (East Tennessee State University, Johnson
City, TN, 37614) LINE POUCHARD (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
One of the most valuable
sources of intelligence for military agencies today is open source intelligence
(OSINT). (1) OSINT embodies all publicly available information. It is becoming
increasingly important to intelligence analysts as knowledge becomes globally
available via the Internet. However, the problem with OSINT is that it is so
time consuming and inefficient for an analyst to sort through all the available
information on any given subject. The goal of this project was to use Semantic
Web technologies and Natural Language Processing (NLP) to enhance the search
capabilities of software tools used by intelligence analysts. The challenge
behind this project was trying to avoid inheriting the search limitations that
come with using only structured data or only natural language. In order to
search structured data, the analyst must know exactly how the data is organized.
Information Extraction based on automatic NLP techniques yields results that
amount to 70% of results produced by a human. By combining the two methods
with Semantic Web technologies like the Resource Description Framework (RDF),
we are attempting to demonstrate that documents can be efficiently searched
and cross referenced. OpenSource.gov files are automatically downloaded from
an FTP server. After extracting the Extensible Markup Language (XML) files,
all of the metadata is stored in a Java data structure. The text body is searched
using Baseline Information Extraction (Balie) to find possible city names.
For each possible city name, if it is found within a country listed in the
XML metadata, then it is stored in the data structure. Finally, all of the
data is used to create an RDF document, which is uploaded to a Sesame repository.
Using Sesame’s web interface, it is possible to query, modify, and browse all
of the data in the repository. A text file was also acquired from geonames.org
containing information and coordinates on over 80,000 cities. Balie was chosen
for named-entity recognition because it is easy to implement and highly configurable.
An alternative to Balie, called General Architecture for Text Engineering (GATE)
was also considered. However, since Balie can use GATE configuration files,
Balie seemed like the most flexible choice. This project focuses on combining
existing tools in a way that has not been done before. There is currently no
standard way to convert XML data to RDF format, but this project is a step
in
that direction.
Purification and Characterization of Recombinant Aequeorea coerulescens Green
Fluorescent Protein from Escherichia coli. MATT PEOPLES
(Earlham College, Richmond, IN, 47374) HUGH O'NEILL (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
Green Fluorescent Protein
(GFP) is a single chain polypeptide that forms a fluorescent chromophore by rapid
cyclization
and subsequent oxidation of residues Ser65-Tyr66-Gly67.
It is widely used as
a fluorescent tag for in
vivo investigations. In this study an efficient procedure was developed
for the isolation and characterization of enhanced recombinant Aequeorea coerulescens GFP
(aceGFP)
that was over-expressed in Escherichia
coli JM109. The first step employed three-phase partitioning to precipitate
GFP using ammonium sulfate and tert-butanol. This was followed by dialysis and
anion exchange chromatography. The purification procedure was monitored by UV/Visible
absorption spectrophotometry, circular dichroism spectroscopy, fluorescence excitation/emission,
and sodium dodecyl sulfate (SDS) and native polyacrylamide gel electrophoresis
(PAGE). Interestingly, two variants of GFP separated during anion exchange chromatography.
The first variant (GFP478) absorbed maximally at 478nm with a fluorescence emission maximum
of 505nm. The yield was 3.04mg GFP478/g cell paste. The second variant (GFP493) had a maximum absorbance at 493nm and an emission maximum of
509nm. The yield of this protein was 11.4mg GFP493/g cell paste. Comparison of the UV/Visible and circular dichroism
absorption spectra of the two isoforms indicate that the environments of their
chromophores are different. Denaturing SDS-PAGE demonstrated that the lengths
of their polypeptide chains are identical; however GFP493 migrated
less than GFP478 by native PAGE, indicating a difference in the tertiary/quaternary
structural characteristics of the two isoforms. GFP has been successfully purified
from recombinant E.
coli in
good yield, and the two resulting isoforms of aceGFP have been characterized.
Small angle x-ray scattering will be used to further investigate the structural
properties
of these two proteins in solution.
Quasielectrostatic Carbon Orientation for Lithium-Ion Battery Applications. CLIFF MCCOLD (Vanderbilt University, Nashville, TN,
37235) JANE Y. HOWE (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
In Quasielectrostatic
Carbon Orientation (QCO) processing, carbon precursor materials are thermally
treated while subject to an alternating current (AC) electric field with
the goal of producing carbon materials with oriented graphene sheets. To
provide proof-of-principle, QCO-treated samples are characterized to determine
if conductive graphene sheets composed of bonded carbon atoms can be aligned
in the direction of the electric field. Carbons with oriented graphene sheets
could potentially be used in lithium-ion battery anodes, permitting higher
charge rates, greater maximum current, and higher power density. A tube furnace
was used to raise the temperature of the precursor material in an inert argon
atmosphere. The material was held in a rig between top and bottom capacitor
plates at different voltages, which applied the field during the entire 24-hour
thermal processing. Variables included precursor materials (Mitsubishi AR
mesophase pitch, phenolic resin), highest temperature
(280°C, 650°C), AC field frequency (200Hz, 10kHz, 700kHz), and electric field
strength (no field, 2.4kV/cm, 6.0kV/cm). Created samples underwent x-ray diffraction
and impedance spectrometry to determine if desired graphene sheet orientation
was achieved. Results indicated that AR mesophase pitch does not respond to QCO
processing at softening temperature (280°C). Severe foaming of AR mesophase pitch
under numerous run conditions up to carbonization
temperature (650°C) excluded carbonized samples from both characterization techniques.
Phenolic resin samples showed QCO treatment-dependant results at carbonization
temperature, but data was from too small a sample population to see clearly defined
trends. Future work includes extensive sample creation under various QCO field
frequencies. The ability to apply a stronger field (6.0kV/cm and higher) was
only recently developed by minimizing capacitor plate separation, and many samples
remain to be created using stronger field conditions. Isotropic pitch and cellulose
are potential future precursor materials. Created samples must be analyzed using
the x-ray diffraction and impedance spectrometry, and scanning electron microscopy
will also be used for future analysis. Once a clear trend in data is observed,
the appropriate precursor material and run conditions will be used to create
samples for direct lithium-ion battery anode testing.
Relationship Between Water Flowpaths, Water Content, and Particle Size in Partially-Saturated
Sediment Samples. LUXI FANG
(Furman University, Greenville, SC, 29613) MELANIE MAYES (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
The transport and fate
of nuclear processing wastes in unsaturated sediments at U.S. Department of
Energy's Hanford Site in Richland, WA is of concern due to the proximity of
the Columbia River. Intact cores (0.2 m x 0.2 m) were collected to study the
effect of sedimentary layering on the hydrologic and geochemical processes
controlling contaminant transport. The goal of this project was to study the
relationship between water content, particle size, and flowpaths in the cores
as inferred using a dye tracer (Brilliant Blue FCF). The dyes are predicted
to follow the water flowpaths and to be found in the most conductive flowpaths.
Kinetic studies determined the rate of dye interaction with two types of soil
samples, Hanford Coarse (HC) and Hanford Dike (HD). We used dye concentrations
of up to 5g/L and set them for different equilibration time periods. An isotherm
batch study was performed in order to determine the distribution of dye among
sediment and solution at different concentrations. Solution samples were analyzed
using UV-visible wavelength spectrophotometry in order to quantify dye concentrations.
This data was plugged into the convective-dispersive equation to predict the
transport of dye through the intact cores and to determine when to dissect
the core. We prepared a dye tracer for the dissection of HC and HD cores at
the highest concentration (5g/L). We dissembled the cores before any dye was
visible in the effluent. The cores were dissected into approximately 9 horizontal
layers at 5 different depths, while photographing the appearance of the dye.
We found the mass wetness of each sample. Since HD and HC are horizontally-oriented
cores where the beds are parallel to the direction of flow, we determined particle
size analysis across cores at one depth. The water content and particle size
were related to water flow paths as inferred by the presence of the dye. The
distribution of dye showed significant preferential water flow and solute transport
for both samples, even though HC sample appeared to be homogeneous. For the
HD sample that consisted of distinct sand and clay layers, the transport was
controlled by visible layering. A relationship between moisture content and
preferential flowpaths was found for HC. The finding suggests that the transport
of the contaminants in the unsaturated Hanford sediments may be mainly controlled
by water content
and particle size.
Revising the Building Combined Heat and Power (BCHP) Screening Tool. RODNEY SMITH (University of Tennessee, Knoxville,
TN, 37996) F. ED PIERCE (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
The United States Government
created the Federal Energy Management Program (FEMP) in order to reduce the electricity
consumption of its agencies. One method by which the program meets this goal
is development and application of combined heat and power (CHP), or cogeneration,
technology. In a typical CHP system, the waste heat from an on-site turbine or
engine is recovered and used for heating the surrounding building or area. In
order to assess the economic feasibility of this technology, a screening must
be performed that simulates the layout and energy usage of a candidate site.
ORNL uses a computer program called the BCHP Screening Tool for this purpose.
However, the particular version of this software in use at the lab is lacking
in its capabilities and appearance. Thus it has been my goal to revise the source
code of this program so as to remove as many such deficiencies as possible. The
revisions made can be divided into three categories: debugging, reformatting,
and upgrading. First, debugging efforts primarily focused on avoiding error messages
that were called inappropriately or at inconvenient times, such as when certain
pieces of equipment were omitted. Next were reformatting changes, which included
revising the system font and layout to something more modern and rearranging
objects where space limitations had cut off words or lines. Finally, upgrading
changes made the program more user-friendly, such as by allowing single-case
simulations and adding additional user-defined parameters. Work is still in progress,
as the screening tool is inherently dated by its Visual Basic/FORTRAN architecture.
Future developments may include interaction with Excel-based input forms and
further modification of the program’s appearance.
Rietveld Full Profile Refinement of MnO and MnAs. DALGIS
MESA and RAHUL PATEL (Florida International University, Miami, FL,
33199) JAIME FERNANDEZ-BACA (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
In the present study,
elastic neutron scattering was used to obtain a powder diffraction pattern
for MnO at the Wide Angle Neutron Diffractometer (WAND) located at the High
Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). The
diffraction pattern obtained from the sample was analyzed using the Rietveld
method of full profile refinement in order to refine the relevant crystallographic
parameters of the specimen. The Rietveld method is based on a least squares
fit of the full diffraction pattern to a model that takes into account the
crystallographic as well as the instrumental parameters to calculate the
full profile. The latter includes the Caglioti resolution parameters (U =
2.36, V = -1.18, W = 0.43) and
the wavelength (Λ) of 0.1476 nm. As a resource, the Inorganic Crystal Structure
Database (ICSD) was used to obtain the initial crystallographic parameters for
MnAs [1] and MnO [2]. The following crystallographic parameters were refined
for MnO using the software program FullProf© (Fortran 90 version, Copyright 2006:
The FullProf© Team): lattice constant values (a, b, c) of (4.44, 4.44, 4.44)
and individual isotropic thermal parameters (B - factor) with an initial default
value (D.V.) of 1. The results yielded a percent change of 0.53 for the lattice
constant while a 52.48 and 44.40 for the B - factors of Mn and O respectively.
For MnAs, the refined crystallographic parameters included the lattice constants
(3.72, 3.72, 5.72), the atomic occupancies (D.V.), as well as the B-factors (D.V.).
The percentage change for the refined parameters for MnAs were of (0.26, 0.26,
0.30) for the cell parameters, 54 and 36 for the atomic occupancy of Mn and As
respectively, and the obtained values for the B-factors were 4.38 and 3.25 for
Mn and As correspondingly. The experimental procedure and results will be discussed
in detail along with new ideas for possible improvement of the present study. [1]
Nowotny, H., Funk, R., Pesl, J., Kristallchemische Untersuchungen in den Systemen
Mn-As, V-Sb, Ti-Sb, Monatshefte fuer Chemie 82, Page 513-525, 1951. [2] Jay,
A. H., Andrews, K. W., Note on Oxide Systems pertaining to Steel-making furnace
slags: Fe O - Mn O, Fe O - Mg O, Ca O -Mn O, Mg O - Mn O, Journal of the Iron
and Seet Institute, 152, page 15 -18, 1946.
Safety Barrier Program to Protect Experimenters in the Event of Pressure Cell
Explosion. RACHEL MORRIS (Maryville College, Maryville, TN, 37804)
LAKEISHA WALKER AND LOUIS SANTODONATO (Oak Ridge National Laboratory,
Oak Ridge, TN, 37831)
In neutron scattering research,
high pressure experimentation with pressure cells is becoming more prevalent.
Although this particular type of experimentation can provide a plethora of information
regarding solutions to geophysical issues as well as hydrogen storage designs,
material analysis at high pressure can be very dangerous. For this reason, scientists
need to take precaution for ensuring their safety when using pressure cells under
extreme conditions. Since pressure cell fragments can be projected if the cell
ruptures or explodes, a safety barrier should be constructed to contain the hazard.
Therefore, I have written a program in Visual Basic for Applications using a
Microsoft Excel spreadsheet interface to help determine an appropriate and cost-efficient
safety barrier. The logic of the program is not only based on calculations derived
from the equations of motion in physics for radial distance and velocity, but
it is also based on equations of acceleration involving the thickness and density
of the cell initially and the amount of pressure used in the experiment. These
calculations are the basis for determining how fast an infinitesimal fragment
(in the worst case-the entire cell) will be traveling at any given distance from
the initial starting position of the cell. The primary purpose of the program
is to use a model of velocity versus distance to aid in determining the dimensions
for a safety barrier that will be impenetrable for the largest fragment traveling
at the highest velocity. Although any cell can be modeled with this program (provided
the user supplies certain values for variables), the Titanium Zirconium (TiZr)
alloy cell is exampled
in this paper, which has a pressure equivalent to 200x106 Pa, a density of 5230 kg/m3, a thickness of 0.0039751 m, and an initial radius of 0.003175
m. The TiZr cell was modeled for 35 steps for 0.000036 s, until the radial distance
of the fragment reached 0.123 m and the velocity reached 195 m/s. Thus, the projected
and desired results were achieved using the program, and the construction of
the barrier will occur in fall 2007.
Sampling and Analysis Methods for Microbial Fuel Cells. SCOTT
CESAR (Western Michigan University, Kalamazoo, Michigan, 49006) ABHIJEET
BOROLE (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Microbial Fuel Cells (MFC’s)
are devices which use micro-organisms as catalysts to oxidize compounds such
as glucose whereby electrons are released and are allowed to flow between electrodes
developing
a potential difference from which usable
power may be drawn. MFC’s are quite simple when viewed yet quite complex when
analyzed. Many factors need to be steadily sampled and analyzed to determine
different parameters within the system. Direct monitoring of system electrical
characteristics with a voltmeter gives open circuit voltage (OCV) and current
output at a given load. A variable-load resistor was employed to obtain a power
density curve in which overall power of the system was determined. The most recent
method involves electrode cycling to obtain higher output of the total system.
Along with electrical measurements, samples of anode and cathode solutions are
taken to determine the performance of the MFC’s. Spectroscopy was used to derive
optical density measurements for determining cell concentrations and also for
determining differing iron concentrations in solution. The solution pH was also
monitored for biological stabilization. High Pressure Liquid Chromatography (HPLC)
was used for glucose and organic acids analysis. The results have shown that
a mediator was required for conduction of electrons from the microbes to the
electrode surface under the conditions tested. Iron was used as a mediator, since
it is cheaply available. From iron analysis, it was found that iron (III) is
electro-sorped on the electrode surface after electron donation. Electrode cycling
was used to maximize power output under these conditions. Further work to facilitate
increased rate of iron desorption is needed to enable stable power output.
Second Order Boundary Derivatives in 3D. EMILY
MITCHELL (University of South Carolina, Columbia, SC, 29225) LEONARD
GRAY (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Boundary Element Method (BEM) is
a numerical technique for the solution of the partial differential equations
that describe physical phenomena. The integral equation formulation contains
the Green's function (fundamental solution of the differential equation) and
its first derivative; as these functions are singular, singular integral evaluation
is an important aspect of the BEM. A boundary integral solution provides complete
knowledge of the primary function (e.g., potential for the Laplace equation,
displacement for elasticity) and its normal derivative on the boundary. An algorithm
for the post-processing evaluation of second order derivatives of this primary
function has been developed. The integral equation expression for these derivatives
contains second (hypersingular) and third order (supersingular) derivatives of
the Green's function, and thus the definition and evaluation of these highly
singular integrals is the key task. In this work, the difference of the interior
and exterior boundary limits of the integral equation is exploited to calculate
the integrals. The difference procedure effectively weakens the singularities,
resulting in finite limiting values, and moreover all non-singular terms vanish.
The limit calculation is made possible by partial analytic evaluation of the
four-dimensional parameter space integrals. The second derivative algorithm has
been implemented for the 3D Laplace and Helmholtz equations. This latter case
involves a more complicated Green's function, and it was necessary to use suitable
Taylor expansions to carry out the limits. The ability to handle the Helmholtz
Green's function indicates that the second derivative methods are generally applicable.
The boundary element method is applicable to areas such as mechanics, acoustic
and elastic wave propagation, and electromagnetism. This new second derivative
algorithm should find application in many of these areas.
Seeding Nucleation for the Production of Diamond Stripper Foils. RYAN COLEMAN (The University of Virginia, Charlottesville,
VA, 22903) ROBERT W. SHAW (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Diamond stripper foils
are implemented by the Spallation Neutron Source (SNS) to convert H- to H+
at the entrance of the accumulator ring. These corrugated nanocrystalline diamond
foils can currently withstand about 800 C of injected charge when exposed to
the 20 Hz, 800 MeV Proton Storage Ring at Los Alamos National Laboratory. Currently,
it is necessary for the stripper foils to have lifetimes in excess of 200 hours
for the operational scheduling of the SNS system to be independent of foil
lifetimes. In light of the scheduled power upgrade for the SNS accelerator,
research in producing stripper foils with longer lifetimes is necessary for
the efficient operation of the SNS facility. Essentially, the production of
diamond films involves two major steps: nucleation and growth. My research
has been conducted to develop a nucleation procedure that is similar to one
that recently appeared in the literature. The diamond films are grown on silicon
substrates, and previously, nucleation sites were created by scratching the
substrate surface in a diamond slurry solution. The new nucleation process
involves depositing an amorphous carbon layer on the silicon substrate and
then sonicating a dense layer of nano-powder diamond particles into the amorphous
layer. These diamond particles act as seeds during the growth process, and
the hypothesis was that this nucleation process could produce diamond films
with higher uniformity. The amorphous carbon layers were deposited on the substrate
surfaces with microwave plasma assisted chemical vapor deposition, and over
the course of many experiments, the deposition variables were adjusted to find
the ideal conditions for seeding. The varied experiments showed that the experimental
apparatus could not yield the uniformity and thickness reported in the literature.
However, we have discovered that the amorphous carbon layer may not be necessary;
simply seeding the silicon substrates can promote the growth of uniform diamond
films. The apparatus has no independent heating source, and the substrate temperature
variable is strongly coupled with the power and pressure variables. This coupling
prevented reproduction of the reported growth conditions, and the reported
nucleation process could not be implemented within the confines of the apparatus.
As a result, the next phase of the research project is to incorporate an independent
heating source
into the plasma chamber.
Selective Electrochemical Oxidation of Sodium Chloride Solution. MAX BASTOW (Colorado College, Colorado Springs, CO,
80903) CHARLENE SANDERS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Activated electrodes placed
in saline solution create an electric double layer composed of opposite charges,
repelling ions of like charge. It is hypothesized that, due to this characteristic
of the electric double layer, it is possible to inject a short anionic pulse
into a saline solution that will selectively oxidize water to produce oxygen.
If the pulse is short enough, it will stop before chloride ions are drawn to
the electrode surface, thus avoiding production of chlorine. This would have
applications to the generation of oxygen and hydrogen from sodium chloride solutions.
Phosphate buffered saline (PBS) was placed into an electrolysis cell and a stimulus
generator was used for controlled charge injection of an anionic pulse. This
pulse was applied for 4 hours in a closed cell and chlorine production was observed
by the spectrophotometric determination of hypochlorite based on its reaction
with ascorbate. The same pulses were then applied to an identical cell containing
PBS sparged with N2 at 50 ml/min. A galvanic cell was used for oxygen measurements,
and a Figaro gas sensor was used for hydrogen measurements. Evolution of chlorine
was not observed until pulse widths greater
than 200 µs were applied. At this pulse width the production of oxygen was already
well established at 0.11 ± 0.01 µmol/hr. At the greatest applied pulse width
of 400 µs chlorine production was at 0.053 ± 0.008 µmol/hr while oxygen production
was 0.25 ± 0.01 µmol/hr. These results show that short pulses are indeed capable
of oxidation of water in PBS to produce oxygen while avoiding the oxidation of
chloride to chlorine.
Semi-Automation of Data Analysis of RTBT Wire Scanners. FEDRICK
REYNOLDS (Tennessee State University, Nashville, TN, 37209) TED WILLIAMS
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Spallation Neutron
Source (SNS) is the most powerful pulsed source of neutrons in the world. SNS
consists of a Linear Accelerator (Linac) that accelerates negatively charged
hydrogen ions (H-) throughout the various regions of the Linac to approximately
88% of the speed of light. However, the region that is focused on is the Ring
to Target Beam Transport (RTBT). In this region, the beam is transported to
the mercury target to produce neutrons that are used for research. During the
transport, the size of the beam is increased, and to produce the maximum amount
of neutrons the beam size and orientation is essential. To ensure that the
neutron production is efficient as possible, the analyzation of data from wire
scanners in the RTBT is necessary. When analyzing data, it is common to perform
the tasks of eliminating outliers and noise caused by various things. These
tasks are many times tedious and time consuming. Therefore, the task was to
modify an existing program that would make the analyzation less wearisome,
and include buttons that would subtract noise and store important values that
would be produced from the analyzation. These buttons were created and placed
in the program RTBT Wizard, a program that analyzes wire scanner data from
the RTBT region of the Linac. These buttons, “Clear
Data,” “Percent of Range,” and “Fit and Store” provides the user with an easy
step-by-step process of analyzing data. The “Clear” button clears a table holding
data while allowing the user to import another set of data to be analyzed.
The “Percent Range” button is used to subtract background noise from being analyzed.
This is essential because the background noise can cause the beam size calculations
to be thrown off, therefore causing over-adjustments by the Linac operators.
The “Fit and Store” button, fits the data with a Gaussian profile and stores
the values of amplitude and sigma. These values determine the beam size and within
the program the orientation and shape of the beam can be calculated with these
same figures. These modifications, while minor on a visible level, were much
needed, and will prove to become great assets for the operators.
Similarity of Critical Experiment Using Sensitivity Analysis. ALLISON
MILLER (University of New Mexico, Albuquerque, NM, 87131) BRAD REARDEN
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Validation of nuclear critical
safety calculations is required to establish the relationship between calculated
keff values and reality. From the International Handbook of Evaluated Criticality
Safety Benchmark Experiments (IHECSBE), critical experiments were examined. Benchmark
experiments that were similar in composition to that of the criticality safety
model were modeled with the use of the same version of computer code, nuclear
data and modeling assumptions as in the criticality safety model. The SCALE 5.1
TSUNAMI -3D is a code in which the sensitivity of the nuclear data is calculated.
This sensitivity defines how the keff of a model or system will be affected for
a given change in a specific nuclide. The goal was to obtain data for the sensitivity
analysis for each benchmark experiment and compare these results to those of
criticality safety model. For the purpose of code validation, direct perturbation
calculations were preformed. A new prototypic SCALE module is being beta-tested
to perform the direct perturbation (DP) calculations, named TSUNAMI -DP. The
expectation is that this module will release with SCALE 6 in 2008. TSUNAMI -DP
generates the direct perturbation Critical Safety Analysis Sequences CSAS files.
The CSAS output files are then examined to validate the TSUNAMI -3D sensitivity
results. Once it is seen that the TSUNAMI -3D results and the direct perturbation
results are within 5% of one another, the sensitivity data files are compared
to those of the cask models; using the TSUNAMI -IP module. TSUNAMI -IP generates
a final value that shows how similar the two models are. TSUNAMI-IP generates
a final value, which states the similarity between the criticality safety model
and the benchmark experiment model. The majority of the critical experiments
that were modeled were not similar to those of the criticality safety model,
and therefore will not be applicable. Continual work is being done to obtain
more critical benchmark experiments that are applicable to that of the criticality
safety model.
Simulating Beam Passage Through the Injection Chicane of the Spallation Neutron
Source. MATTHEW PERKETT (Denison University, Granville, OH,
43023) JEFF HOLMES (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The
Spallation Neutron Source (SNS) is an accelerator-based neutron source that
will become the most powerful device of its kind when full power of 1.4 MW
is achieved in 2009. Such a powerful source has a correspondingly small tolerance
for uncontrolled beam loss, which leads to activation of the facility and
longer maintenance times. To meet radiation requirements at such high energies,
only 1/10,000 of the particles can be lost due to collision with the beam
pipe. According to recent measurements, the area with the worst beam loss
is in the injection chicane and beam dump line. Due to a structural flaw,
this region will eventually need to undergo physical modification, so it
is critical to accurately track the particles’ paths. Previous studies have
been conducted using a piece-wise symplectic magnetic field approximation,
but it is now essential to track particles with greater precision using a
3D multipole expansion representation for the magnetic field. To achieve
this, a large portion of time was devoted to coding, testing, and adding
C++ modules to the new Python wrapper of the Objective Ring Beam Injection
and Tracking code (pyORBIT). PyORBIT is an accelerator physics code that
utilizes a Message Passing Interface (MPI) for parallel computing capabilities,
which is being developed at ORNL and used by accelerator facilities worldwide.
Multiple benchmarks completed in the weeks leading to the final measurements
agreed well with results calculated by hand. Tracking a Gaussian distribution
of particles with SNS injection parameters from the primary stripping foil
to the secondary stripping foil at a kinetic energy of 1.0 GeV resulted in
a physically realized position and momentum confirming code integrity. It
was found that the 3D magnetic field produced 66mm separation between H0 and
H- components
while the piece-wise symplectic only found a 61mm separation. This higher
separation could account for a greater difficulty getting the beam to enter
the dump line and the observed high losses in that region. The next logical
project will be to utilize the new modules in pyORBIT for a 3D magnetic field
from the secondary foil down the dump line.
Simulating Land Competition for Biomass Energy, Forestry and Agriculture:G-FALUM,
Global Forestry and Agricultural Land Use Model. ZHENG
MI (Colorado College, Colorado Springs, CO, 80903) ANTHONY KING (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
This research addresses the
competition for land to simultaneously satisfy growing biomass energy, forestry
and agricultural demands as part of sustainable energy and carbon management
strategies within the context of CarMan, a global carbon management analysis
model. A review of existing land use models (FASOM, AgLU and KLUM) identified
insufficiencies for addressing biomass energy land-use in CarMan. In response
we developed a new Global Forestry and Agricultural Land-Use Model, G-FALUM.
G-FALUM is designed to simulate the competition for land from biomass energy,
forestry and agricultural production over a period of 100 years. Numerical optimization
methods in Mathematica
are used to model the virtual land
owners’ decisions to allocate land to different forestry and agricultural products.
It allows plants used as biomass feedstock for renewable energy production to
be included in either/both forestry and agricultural product lists, so that biomass
energy production directly competes for land with other forestry and agricultural
products based on their varied profitability. Three different scenarios were
designed to test the land allocation component of G-FALUM. The first scenario
demonstrates that the model properly simulates decreasing return to land scale
and can avoid the problem of devoting all the land to a single monoculture of
most profitable product. The second and the third scenarios assign a high yield
to pulpwood biomass feedstock (poplar, willow) that competes for land with a
low yield forestry product (natural forest), a medium yield agricultural product
(potato) and the option of idling the land (not planting anything). The model
rationally favors the high yield pulpwood by allocating more land for this use,
and assigning significantly less land to the rest of possible land uses. When
the simulation starts with a skewed land use allocation that devotes all the
land to pulpwood plantation (scenario 2), the model’s virtual land owner develops
this monoculture forest into a land with 69.9% pulpwood, 1.4% potato and 28.7%
of natural forest land in 15 time steps (time step unit is a year). Beginning
at the 8th time step, the land share converges towards the stable share in the
15th time step with an error of 1%. In the third scenario, the model starts with
a monoculture of potato. After 25 time steps, the virtual land owner develops
the land into 70.0% pulpwood, 1.4% potato and 28.6% natural forest land.
Software Development for a New OSCAR GUI that Will Support the Use of Virtual
Machines. NATHANIEL GRAHAM (University of New Mexico, Albuquerque,
NM, 87106) STEPHEN L. SCOTT (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Open Source Cluster Application
Resources (OSCAR) facilitates the installation, administration, and programming
of Beowulf
type high performance computing (HPC) clusters. OSCAR has a variety of pre-packaged
applications and utilities which allow one to install and manage clusters without
specific technical expertise. An expanding interest in virtualization today has
shown that virtual machines are a suitable solution to address issues for application,
execution, and system management. However, the support of virtual environments
in OSCAR is an ongoing effort, particularly regarding the user interface employed
by OSCAR which is not currently optimized for management of virtual machines.
The current OSCAR graphical user interface (GUI) was improved to better facilitate
its use for managing virtual machines. The new OSCAR GUI was based on out of
date OSCAR code. The project was divided into two phases: (i) the refactoring
of existing code and (ii) the adaptation of the code to manage virtual environments.
The base OSCAR code came from earlier GUI work that had fallen out of the main
development path. That specific GUI project was never finished and was not maintained
for a number of years. My first task was to modify the code to make it work with
the current OSCAR architecture. It is now possible to launch the original GUI
with all options available. The second phase was the adaptation of the code to
virtual environments. For instance, compared to a standard execution platform,
virtual environments are significantly more dynamic (virtual machines are created/destroyed
on demand). For that I designed a new set of widgets for “node sets” and “package
sets” management, and the mapping of virtual nodes onto physical nodes. The ultimate
goal of my project was to provide a well-defined GUI for the management of virtual
environments while maintaining the original Beowulf cluster installation abilities.
This GUI will be integrated into OSCAR-V, the virtualized OSCAR infrastructure
package, as the interface by which the user will manipulate OSCAR-V virtual environments.
Soil and Water Assessment Tool for a Population Viability Analysis of the Endangered
Shortnose Sturgeon (Acipenser brevirostrum). KENDALL
ERNST (Stanford University, Stanford, CA, 94305) YETTA JAGER (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
The shortnose sturgeon
is a federally endangered fish species found in the Ogeechee River System (ORS).
Efforts are being made to ensure the persistence and support the expansion
of the species; among these efforts is an increased awareness of the affect
of land use on sturgeon habitat. The land use on and around the watersheds
of a river have a direct impact on the water quality of the river, raising
the question of how altering land uses will improve sturgeon chances of persistence.
To answer this question, a Population Viability Analysis (PVA), in this case
a computer model receiving inputs of water quality and hydrodynamics, will
model individual sturgeon and provide information regarding extinction risk
over an extended period of time. For the purpose of providing input, three
models for the ORS will be implemented using the Water Quality Analysis Simulation
Program (WASP), the Environmental Fluid Dynamics Code (EFDC), and the Soil
and Water Assessment Tool (SWAT), which are respectively a water quality model,
a river hydrodynamics model, and a watershed and water quality model. During
the first year of the PVA project, the SWAT model has been most heavily emphasized
because of its utility in discriminating among watershed influences on water
quality. The EFDC and WASP models will be used later in the project when tidal
variations will be considered within the ORS. SWAT requires several types of
input to produce results. These are: land cover data, soils data, a digital
elevation model (DEM), and stream flow lines. At this point in the project
the model has been run, however, the model has not been calibrated. The process
of calibration is as follows: the model is run with the current data, the results
of the simulation are then compared to real data collected in the field, the
input data is altered or upgraded, and the process is repeated until model
output closely resembles real data. The ORS runs through a Fort Stewart military
base as well as urban development and upstream agriculture. The goal of the
model is to differentiate between the water quality contributions of the military
base and urban land, as well as experimenting with the alteration of current
land uses to see the effects on the water quality of the ORS, and then use
each result in the PVA model. The model is part of a three year project, including
the acquisition of several more datasets from the ORS through field
work.
Solving Ill-conditioned Linear Systems in High-Precision Arithmetic. JASMINE GARNER (Lane College, Jackson, TN, 38301)
ED D'AZEVEDO (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
A linear system of equations
is a set of linear equations in variables that can be represented in matrix form,
where
it is called the matrix coefficient of linear systems. A small change in the
coefficients produces a large change in the solution and the system becomes ill-conditioned.
The most efficient way for solving linear systems is the Gaussian elimination
method, but this method itself is not always valid to the ill-conditioned cases.
The goal of this project is to explore effective methods such as using high-extended,
precision arithmetic library software for solving ill-conditioned block tridiagonal
linear systems. The linear system is not too ill-conditioned but intermediate
results may be ill-conditioned and can lead to instability. The idea is to use
higher precision arithmetic to regain stability and accuracy. A dense direct
solver using Gaussian elimination with partial pivoting from LAPACK (Linear Algebra
Package) is modified to use higher
precision. The solver computes a "LU" factorization where the matrix
equals a lower triangular L multiplied by an upper triangular matrix U. The LAPACK
is one commonly used library for performing numerical linear algebra computations.
Both C++ and Fortran-90 high-level language interfaces are provided to permit
one to convert an existing C++ or Fortran-90 program to use the library with
only minor changes to the source code. LAPACK is written in Fortran since the
language is commonly used for numerical computation. The code with extended precision
was used to explore the range block sizes and number of blocks where the approach
is effective by collecting runtimes and computed errors. A parameter (beta) controls
scaling and conditioning of the system and as beta increases, the maximum error
in solution increases as well. The measured runtimes decreases at the same rate
as the number of block sizes increases in the data of fixed number of blocks.
The results are summarized in plots. Although the runtimes are often lengthy,
using a high-level program language to solve difficult linear equations permits
faster development of large problems.
Spallation Neutron Source (SNS). YAN-JIUN
CHEN (National Taiwan University, Taipei, N/A, 104) ROBERT W.
SHAW (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Spallation Neutron
Source (SNS) uses a Multi-Turn Charge-Exchange Injection to form short
pulses of protons in its accumulator ring. Carbon stripper foils are
used in this process for removing electrons from the incoming H- Linac
beam. Testing at various facilities has shown diamond stripper foils
have an expected lifetime of more than 100 hours, five times that of
evaporated carbon ones. Longer lifetimes can reduce beam downtime for
replacement. This project involves producing diamond foils for the SNS
and other accelerators. Diamond foils are grown via microwave plasma
enhanced Chemical Vapor Deposition (CVD) on patterned silicon substrates.
Substrates are patterned using photolithography, and etched chemically
to produce corrugations 5~7 µm deep around the edges for mechanical stability
of films. To enhance nucleation, the substrate surface is abraded with
diamond
powder slurry in an ultrasonic bath. Subsequently, 1~2 µm thick nano-crystalline
diamond films are grown on the substrates under 1000 W of microwave power and
130 torr with a gas mixture of 2% CH4, 8% H2, and 90% Ar. The substrate is then
partially removed with a 1:1:1 mixture of hydrofluoric acid, acetic acid, and
nitric acid, leaving a silicon edge for support of the foil. The main focus of
the project is to optimize the performance of these diamond foils. Recently,
foil areas have been increased by 57% to minimize beam loss, and foil thickness
has been increased to maximize efficiency. Scanning electron microscopy (SEM)
of the foils has revealed imperfections in the films, including black spots and
pits. Black spots have not been proven to affect performance. Nevertheless, they
can be successfully removed by etching away the surface of the film in a pure
H2 plasma. They are also suppressed with a lower growth pressure. Pits, ranging
from 1 µm~10 µm wide, are suspected to cause loss of stripping efficiency and
may result in holes or weak spots in foils. These pits are mainly caused by dust
particles during the patterning of the substrates. Special attention is now paid
to the preparation of substrates to minimize these occurrences. A cloudy visual
appearance signifies uneven nucleation densities and/or substrate roughness.
As a result, adjustments to the duration of ultrasonic abrasion are being made.
Further testing in the SNS will reveal whether these measures lead to greater
efficiency and longer lifetimes of foils.
Strategic Planning for the Neutron Sciences Directorate: The Suggested Guidelines
for the Content and Layout of the Annual Report. KELLEY
COFFMAN (Vanderbilt University, Nashville, TN, 37235) AL EKKEBUS
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
The Oak Ridge National
Laboratory Neutron Sciences Directorate (NScD) encompasses two world-class
user facilities for studying materials with neutron scattering - the Spallation
Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). As the Neutron
Sciences’ facilities emerge into a competitive worldwide market, a need
exists for outreach to the scientific community. The larger component of
my project involves outreach to a variety of audiences through scientific
writing and creative design. More specifically, I headed the strategic
planning of several neutron sciences publications such as scientific application
fact sheets, a user orientation packet, and the future annual report. An
annual report highlights achievements, developments, and operations of
each facility and will be a requirement of the NScD once both facilities
become operational. In conjunction with my strategic planning project,
I formulated suggestions for the content and layout of the publication
after engaging in research methods such as benchmarking, surveying, and
outlining. The first step in outlining the report involved formulating
a table of contents, which required benchmarking other top neutron facilities’ reports.
Additionally, I interviewed and surveyed NScD staff and scientists as well
as the public and internal websites to integrate the missions and priorities
into my suggestions. This also resulted in an array of perspectives on
which aspects of the design should be emphasized. I then compiled an outline
of my suggestions for content combining both tried and unique approaches
to each section such as the page lengths, the groups to consult for information
in each section, and the topics to address. In addition, I designed sample
layout pages to illustrate my recommendations using advanced design software.
The suggestions formulated for the NScD annual report strive to bridge
the need for public outreach with representing two world-class neutron
facilities.
Successful Integration of Staff and Users into Oak Ridge National Laboratory's
Neutron Sciences Directorate. JENNIFER
STINNETT (University of Tennessee, Knoxville, TN, 37830) CHRISSI SCHNELL
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
For any scientific research
laboratory to become one of the foremost facilities, it is crucial to attract
and retain the best employees. To do this, a laboratory must be attractive to
employees not only within their field of research, but also with the way they
present their community and its resources. Oak Ridge National Laboratory (ORNL)
is no exception. My project involves researching and exploring different methods
to help attract new staff and users and to then help integrate them into ORNL,
and more specifically to my project, the Neutron Sciences Directorate (NScD).
Previously, the NScD was relying on a website that provided inadequate information
to incoming employees and visitors. The scope of information provided was minimal
and the coverage was lacking. As part of my project, I surveyed, gathered and
organized new information, and enhanced the content of the present information.
Based on the needs expressed by new staff, the information ranged from how to
get a social security card to a list of local movie theaters. The information
collected was vast and varied, but was all relevant and informative, and was
information of interest to new and/or international persons. My project also
consisted of building a new web community for NScD employees. For this I used
Publisher, Photoshop and PowerPoint.
The community, tentatively entitled "Friendship
Web" allows employees to connect to one another outside the office. Employees
voluntarily register and create their own page; complete with a picture, contact
information, and any optional personal information they wish to include. They
are then able to select their interests/talents/activities from a database, which
are also listed on their page. This allows NScD employees to log on and find
colleagues with shared interests; helping foster stronger relationships and a
healthier work environment. It is also crucial to helping new employees feel
welcome, and can prove resourceful when needing to locate employees who speak
certain languages for translation purposes. The final part of my project consists
of photographically documenting the NScD. Upon completion of this portion, new
organization charts will be constructed, and locating and identifying people
will be easier than the current method, which is solely on the internet and is
not comprehensive. My project makes the transition into ORNL’s NScD seamless,
and also creates a better work environment for those already employed.
Super-hydrophobic Behavior on Nano-structured Surfaces. DANIEL
SCHAEFFER (Brigham Young University-Idaho, Rexburg, ID, 83460) JOHN T.
SIMPSON (Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Super-hydrophobic behavior
has been observed in various natural occurrences such as the leaves of the lotus
plant and has been thoroughly studied over the past few years. Water repellant
properties of water drops on uniform arrays of vertically aligned nano-cones
were investigated to determine the highest achievable contact angle (a measure
of water drop repellency), which is measured from the reference plane on which
the drop sits to the tangent line of the point at which the water drop makes
contact with the reference plane. At low aspect ratios (height versus width of
the nano-cones), surface tension pulls the water into the nano-cone array, resulting
in a wetted surface. Higher aspect ratios reverse the effect of the surface tension,
resulting in a larger contact angle that causes water drops to roll off the surface.
Fiber drawing, bundling, and redrawing are used to produce the structured array
glass composite surface. Triple-drawn fibers are fused together, annealed, and
sliced into thin wafers. The surface of the composite glass is etched with H2O:NH4F:HF
etching solutions to form nano-cones through a differential etching process and
then coated with a fluorinated self-assembled monolayer. Cone aspect ratios can
be varied through changes in the chemistry and concentration of the etching acid
solution. Super-hydrophobic behavior occurs
at contact angles >150° and it is predicted and measured that optimal behavior
is achieved when the aspect ratio is 4:1, which displays contact angles =175°.
Super-hydrophobic behavior on uniform arrays of vertically aligned nano-cones
demonstrates synthetic fabrication of super-hydrophobic surfaces is genuinely
achievable by this process.
Synthesis and Integration of Carbon Nanofibers for Nanobiological Applications. PATRICIA REYNOLDS (University of Toledo, Toledo, OH,
43606) MICHAEL L. SIMPSON (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
Recent advances in the controlled
synthesis of nanomaterials are enabling new approaches for probing biological
system functionality at the nanoscale. Several CNMS projects incorporate one
such nanomaterial, carbon nanofibers, as functional elements. Applications include
the use of carbon nanofibers as nanoelectrodes, as means for gene delivery, and
as the principle component of biomimetic membranes. Current efforts make use
of vertically aligned carbon nanofibers (VACNF) as suspension supports for lipid
bilayers (LBL). There are two main purposes; one is to develop techniques to
form LBL structures and secondly to use them as a platform to study integral
membrane proteins and their interactions using neutron scattering. Carbon nanofibers
are synthesized in a plasma enhanced chemical vapor deposition process from metal
(nickel) catalyst, and the vertical alignment results from the applied electric
field during synthesis. The growth process allows for controlled synthesis as
the parameters (e.g., length, diameter, shape, position, and chemical composition)
of individual nanofibers can be selected by definition of catalyst properties
and growth conditions. LBLs are composed of phospholipid head groups which are
hydrophilic and hydrocarbon centers which are hydrophobic. To fabricate hybrid
structures composed of VACNF arrays with deposited LBLs, small unilamellar lipid
vesicles were generated through the sonication of LBLs, deposited on VACNF arrays,
and heated to 35 degrees C for 30 minutes to encourage layer development. Atomic
Force Microscopy was used to map the VACNF array surface both before and after
LBL deposition, and encouraging initial results were acquired to show a change
in surface topography that is indicative of the formation of a LBL on the nanofibers.
The next step in this work is to image these hybrid structures with neutron scattering
to validate the presence of a
suspended LBL on the surface of carbon nanofibers.
Synthesis of Novel Anion Receptors for Seperation. TRINA
HAYES, BETHTRICE THOMPSON and KIMBERLY TUCKER (Jackson State University,
Jackson, MS, 39209) BRUCE MOYER (Oak Ridge National Laboratory, Oak
Ridge, TN, 37831)
Synthesis of Novel Anion
Receptors for Separations Bethtrice Thompson, Trina Hayes, Kimberly Tucker,
Alamgir Hossian Jackson State University, Jackson, MS FAST Bruce Moyer, Peter
Bonnesen Chemical Science Division Oak Ridge National Laboratory Many anionic
species have become a major environmental and health concern. For example
nitrate is an agricultural contaminant in soil and is also present in large
quantities of radioactive waste. As for the health concern, nitrate that
is above the US Environmental Protection
Agency’s regulated contamination level in ground water has caused an increase
in bladder cancer in women. These major concerns have led researchers to develop
anions receptors that can detect, bind, separate, and remove anions from the
environment. To address such needs, we have been carrying out the synthesis of
monofunctional, difunctional, and trifunctional thiourea compounds and their
guanidinium derivatives. We followed a multi-step synthesis in which our starting
compounds are isothiocyanate and amine which are converted to the desired thioureas
followed by methylation and aminolysis to afford the guanidinium derivatives.
Making and breaking covalent bonds is applied to construct desired molecules.
The new compounds are analyzed by NMR spectrometry. It is planned to obtain crystals
from the compounds in order to determine their molecular structures by X-ray
Crystallography. These receptors will be used for binding and separation of the
target ionic species in complex mixtures. Binding properties of synthesized molecules
for anions will be tested in different solvents using NMR spectrometry. This
study will provide ground work for future cleanup and vitrification of USDOE
wastes and environment streams.
Systems Genetics: Elucidating Networks that Underlie Heritable Variation in
Adipose Function and Susceptibility to Obesity. IAN-JAMES
MALM (Macalester College, Saint Paul, MN, 55105) BRYNN VOY (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
Obesity and its co-morbidities
are rampant in Western society. Excess adipose tissue not only physically stresses
the organism but also disrupts homeostasis through release of adipokines, bioactive
molecules produced in adipose tissue. The long-term goal is to determine the
mechanisms by which heritable differences in adipose function impact risk for
obesity and its consequences. Systems genetics was employed by anchoring phenotypic
variation to naturally occurring genetic polymorphisms in two mouse genetic
reference populations (GRP): 1) recombinant inbred BXD (C57BL/6J X DBA/2J)
strains, and 2) a panel of eight genetically diverse strains that serve as
progenitors for the collaborative cross (CC), an emerging GRP. Body and fat
pad weights, plasma hormone profiles and adipose expression of adipokine genes
were measured in males of twenty-four BXD strains and in both sexes of the
eight CC parental strains. Current progress demonstrates: 1) adiposity is highly
correlated with expression of some adipokine genes (e.g., leptin, r2= 0.626;
p=5.4E-6) but not others (eg., visfatin, r2=0.012, p=0.937); 2) a subset of
tightly intercorrelated adipokines are regulated independent of adiposity;
and 3) sexually dimorphic relationships exist among adipokines and adipose
weight. Ongoing assay of adiposity in emerging generations of CC mice confirms
that this new GRP will provide physiological diversity reflective of its genetic
diversity and on par with that in a human population, highlighting its power
to dissect the molecular components of complex traits. Collectively the results
suggest that factors in addition to adipose mass need to be considered when
predicting genetic risk for conditions co-morbid
with obesity.
Testing the Multiwavelet Representation of Functions. OWEN WORLEY
(Dartmouth College, Hanover, NH, 3755) GEORGE FANN (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
The multiwavelet transformation
of functions is one of the most promising methods for analyzing and performing
operations on them. The multiwavelet expansion represents functions in
terms of a basis of discontinuous multiwavelet functions, which are nonzero
over a unit domain.
In particular, representations of the Green’s function of operators of partial
differential equations, constructed in multiwavelet bases, can be proven, in
many cases, to be sparse and nearly diagonal. Thus, the computational complexity
of the application of these operators is linear or nearly linear with respect
to the problem size, and so is very attractive as a method of solution. As in
the development of any complex software, testing must be done to assure that
the transformed function behaves correctly with respect to basic algebraic and
calculus operations. This testing is done by creating and inputting a variety
of functions into a program, calculating the multiwavelet representation of these
functions, applying a number of operators to both the original and transformed
functions, and comparing the results, demonstrating that operating on the multiwavelet
representation is numerically stable and achieves the required accuracy. Said
testing demonstrated that the transformed functions do behave correctly with
respect to the algebra and calculus operations tested to a high degree of accuracy.
Also, as the tests were scaled to higher numbers of processors, the completion
times decreased in a smooth log curve. These results were expected, but in obtaining
them, debugging was performed and problems were identified and worked around.
Further testing should be performed on functions represented with a higher wavelet
order, and testing should generally be done as the code is modified and improved.
The Joule program, written by George Fann and Robert Harrison, performs the multiwavelet
transformation which is tested. The paper, Adaptive Solution of Partial Differential
Equations in Multiwavelet Bases, by B. Alpert et al, provides background on multiwavelet
transformations.
The Application of Surface Enhanced Raman Scattering (SERS) to Pollen Identification. BRADLEY LANDGRAF (Allegheny College, Meadville, PA,
16335) MENG-DAWN CHENG (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
The current method of
pollen
identification—collecting pollen grains on filters, examining each grain with
a microscope, and comparing
the grain with a reference—is a timely and tedious process in need of modernization.
Raman spectroscopy can be used to identify pollen species, but this method suffers
from a low signal strength that can make identification difficult. To address
this low signal, a technique known as Surface Enhanced Raman Scattering (SERS)
was developed. SERS involves the adsorption of nanometallic particles or surfaces
(silver, gold, or copper) to analyte molecules. While SERS has been used to identify
a number of biomolecules, little work has implemented SERS in pollen identification.
Accordingly, this study focused on finding a synthesis and adsorption method
that yielded the most effective signal enhancing silver nanoparticles. The syntheses
involved
the reduction of silver nitrate (AgNO3)
with either sodium citrate
(Na3C6H5O7)
or sodium borohydride
(NaBH4)
to yield
elemental silver (Ag0) nanoparticles. Several techniques were used to adsorb the nanoparticles
to the pollen grains, such as air-drying and aerosolization. The pollen grains
of interest were from three species of plants—common ragweed (Ambrosia
artemisiifolia), eastern white pine (Pinus
strobus), and smooth tag alder (Alnus
incana
ssp. rugosa)—indigenous
to the eastern U.S. and known for their allergenicity. Spectra for each pollen
species were obtained and compared to Raman spectra taken without SERS to see
which synthesis and adsorption method provided the best Raman signal enhancement.
The NaBH4-synthesized
silver applied by aerosolization produced the best spectra by eliminating some
of the background noise associated with Raman spectroscopy, however, no significant
enhancement occurred with either synthesis. Aerosolizing the silver colloid was
the most effective application method, as all other means of application caused
too much silver to be adsorbed to the pollen grains. Future research involving
alternative silver nanoparticles syntheses, whether or not gold or copper may
be more effective, and the mechanization of aerosol application to the pollen
should be completed, as SERS is a technique that could play an integral role
in developing an analytical instrument capable of identifying pollen grains in
situ. and in real time.
The Effect of Metal Deposition on the Electro-Optical Properties of Single
Wall Carbon Nanotube Networks. JOHN HUNT
(University of Tennessee, Knoxville, TN, 37916) ILIA IVANOV (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
Single wall carbon nanotube
(SWNT) networks exhibit high flexibility and optical transparency which make
them perfect candidates to replace brittle and expensive indium tin oxide (ITO)
as electrodes in displays. However, SWNT networks do not have the excellent
conductivity of individual carbon nanotubes due to the high resistance of nanotube
bundles and nanotube-to-nanotube junctions. The focus of this research project
was to explore the deposition of metals on SWNT networks as a means to improve
their conductivity, without sacrificing transparency. SWNT networks were deposited
on the surface of glass and varying amounts, ranging from 1 to 10 nm, of Au,
Pt and Pd were deposited via physical vapor deposition. The optical absorbance
and sheet conductivity of SWNT networks were measured for each metal loading.
Small metal loadings (~1nm) were found to increase conductivity by approximately
50% with a 6% average increase in absorbance. Analysis of absorbance and conductivity
measurements both indicated electronic interactions occurring between SWNTs
and deposited metal. Temperature-resistance measurements were used to determine
the nature of this interaction, which was shown to be the reduction of barrier
hopping resistance at nanotube-nanotube
junctions.
The Effects of Vertically Aligned Carbon Nanofibers on Mitosis. LINA HU (Washington University in St Louis, St Louis,
MO, 63105) TIM MCKNIGHT (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
One of the methods used to
deliver DNA into a cell is microinjection, where macromolecules are directly
administered
into a cell, thereby overcoming a cell’s physical and chemical barriers. Recently,
a technique termed 'impalefection’ has been developed, where high aspect ratio
spikes of either carbon nanofiber or black silicon are used to impale and deliver
DNA on a parallel basis to many cells at once. Morphologically, these high aspect
ratio materials are similar to microinjection needles but can also be compared
to asbestos fibers and vitamin B2 crystals, both of which are known to interfere
with mitosis by hindering the formation of the spindle apparatus and chromosome
segregation. As such, experiments were conducted to determine whether vertically
aligned carbon nanofibers (VACNFs) and black silicon can cause similar interference
during mitosis. A variety of tests were conducted such as live cell imaging of
mitotic events following cellular impalement on these spikes and fixed cell assays
following impalement and/or culture of cells upon nanoneedle arrays. Live cell
imaging following nanofiber impalement showed several occurrences of mitotic
arrest (metaphase checkpoint) and mitotic abort, ultimately resulting in multinucleation
in the Chinese Hamster Ovary (CHO) cell line. Based on this, a series of tests
were conducted in which the mitotic index and multinucleation of impaled and
non-impaled CHO cells were evaluated over time. Cells were cultured in conventional
dishes, upon chips of high aspect ratio structures (unimpaled), and impaled upon
spikes of these structures. The mitotic index and multinucleation of the samples
were scored at 16, 40, and 64 hours. Preliminary data indicates that there are
statistically significant differences in multinucleation between conventional
dishes and growth upon substrates of these high aspect ratio nanomaterials, as
determined by the Student T-Test with a p-value of 0.05. Continued testing will
determine if these differences are more pronounced with impalement of the cells.
These tests will help determine whether growth and impalement on high aspect
ratio substrates cause a disturbance in mitosis, and will provide an assay by
which substrate modifications can be evaluated to counter these effects. Future
modification of the VACNFs to minimize mitotic disturbances could possibly be
applied to gene delivery and other intracellular applications of these nanostructured
materials.
Thermodynamic Analysis of ITER’s Cooling Water System. SHAWN
WACHTER (Pittsburg State University, Pittsburg, KS, 66762) DR. JUAN FERRADA
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Shawn Wachter Pittsburg State
University, Pittsburg, Kansas SULI Dr. Juan Ferrada Nuclear Science and Technology
Division Oak Ridge National Laboratory RESEARCH ABSTRACT ITER, the International
Thermonuclear Experimental Reactor, is currently being constructed in Cadarache,
France by an international consortium including the United States. FlowITER is
a simulations package designed at Oak Ridge National Laboratories to study the
operations of ITER's cooling water system. ITER is an experimental magnetic confinement
fusion reactor designed to produce plasmas capable of sustaining controlled fusion
reactions. It is expected to be the first reactor to produce up to 5 times more
thermal energy in steady state operations than is consumed through auxiliary
heating, and is forecast to sustain steady state operations for a 500 second
fusion pulse. Water will be used as the cooling fluid in the reactor and will
transfer heat, or power, away from the reactor. As it is an experimental reactor,
the cooling water system will not actually generate electricity but rather will
transfer power to a heat rejection system. The United States is responsible for
the design and construction of the cooling water system. The focus of our project
is to design a software package capable of accurately simulating the operations
of the cooling water system. The simulation platform is FlowJava, which is written
in Java, and the participating models
are written in Python. The tokamak’s coolant subsystems include the Divertor
/ Limiter system, the Primary First Wall / Blanket system, the Neutral Beam Injector
system, and the Vacuum Vessel system. By accurately modeling the behavior of
the various cooling systems, problems can be predicted in the design stage and
construction delays can be avoided.
Two Case Studies of Reversibility in Computational Methods. JOHN WRIGHT
(Mercer University, Macon, GA, 31207) KALYAN S. PERUMALLA (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
Currently state-saving is employed
in many large simulations to realize rollback. Reverse computation is a recently
proposed method which computes previous states instead of saving them. This approach
can be beneficial on large machines as computing power is abundantly available
and is possibly more efficient than retrieval from memory. This project investigates
the reversibility of the well known Newton-Raphson root finding method and the
possibility of developing a reversible interface for the Level 1 (vector) operations
found in the Basic Linear Algebra Subprograms (BLAS) library. The mechanics of
Newton-Raphson were studied and an algorithm was developed to reverse each iteration
in the forward method. The reverse method involves finding the root of a derived
function and forward Newton-Raphson is used on the derived function. Consequently,
reverse Newton-Raphson gains the strengths and weaknesses found in Newton-Raphson.
The reverse method has produced favorable results on functions that converge
with forward Newton-Raphson. Unfortunately the forward method behaves unpredictably
when multiple roots, periodic behavior, local minima, etc. exist in the target
function and the reverse method will also produce unpredictable behavior in these
cases. Further research is needed to handle unpredictability in certain functions
in the reverse method. Routines in the BLAS Level 1 were analyzed and candidates
were chosen based on the need for reversibility. Only those routines which modify
input values require reversal. Reverse routines were developed for Givens rotation,
vector scale, vector swap, and vector scale and update (saxpy). The reverse routines
have shown identical scaling to their forward counterparts, however some problems
concerning precision need to be resolved. Further work is needed to improve the
interface to realize transparent reversibility for the vector copy operation.
The forward BLAS library
will need to be modified to implement copy reversibility.
Using Kepler Scientific Workflows to Automate Processing of Data from Scientific
Models. MATTHEW DEVRIES (Vanderbilt University, Nashville,
TN, 37235) SCOTT A. KLASKY (Oak Ridge National Laboratory, Oak Ridge,
TN, 37831)
As a Leadership Computing Facility,
Oak Ridge National Laboratory (ORNL) is home to several large-scale scientific
models that take advantage of the advanced supercomputing power available here.
These models generate gigabytes of data, which must be archived, processed, and
transferred to other locations before the output can be analyzed. Currently,
each of these steps requires the use of separate tools, each with its own syntax
and options. The aim of this project is to automate these processes in such a
way that researchers can easily watch the results as a model is running. This
is being done with Kepler scientific workflow software, which provides a flowchart-like
interface for designing a script that can be executed from the command line.
Using such a workflow that had previously been designed for a scientific model,
new workflows are being developed for S3D, a state of the art direct numerical
solver combustion model that runs on the entire Cray XT4 system. When finished,
these will automate various parts of processing the data, as well as feeding
into an AJAX dashboard, being developed separately, for real-time monitoring.
For researchers using these models, this project should mean fewer tools to master
and an easier time managing their data and monitoring their models as they run.
On the development side, this project will provide feedback on the suitability
of the Kepler software for this application, as well as possible improvements
for the software and the process.
Using Math to Determine Optimal Placement for Wireless Access Points. KELLEN O'CONNOR (University of Tennessee, Knoxville,
TN, 37919) DON WILLIAMS (Oak Ridge National Laboratory, Oak Ridge, TN,
37831)
Intranet and Internet networking
have become a huge part of the operating strategies of many large organizations.
Many
organizations use networking to keep in contact with their employees, inform
their employees, and to communicate among one another. It used to be that desktop
computers were the standard, and laptop computers were only for the elite, used
when absolutely necessary. Now, the world of electronics is focusing on smaller,
more portable devices to make it more convenient for people to travel with their
devices. So, the challenge for the organizations is to continue communication
with these portable devices. The main method used is Wi-Fi, or wireless. Once
a novelty, wireless communication has become a necessity in any large organization.
Because wireless communication is a relatively new concept, there are not really
any standards in place for the placement of wireless transmitters/receivers,
wireless access points (AP’s). The goal of this project was to determine a mathematical
equation that could be used to determine signal strength at different distances
from the AP, so the AP’s could be placed in buildings by evaluating signal strength
needs in certain areas. To determine this equation, I used a handheld signal
strength measuring device. I setup the AP in a central location and recorded
the signal strength at distances in intervals of five feet from the AP. I first
measured the signal strength five feet from the AP, then again ten feet, fifteen
feet, and so forth. I recorded that data and plotted the points on a graph. Visually,
it was obvious to tell that the signal strength was linearly related to the distance
from the access point. I used linear regression to determine an appropriate equation
to relate the two variables, distance versus signal strength, and the data fit
nicely. The results of this research are quite helpful in the information technology
world; however, further research could also benefit the IT professionals. There
are other factors to consider when setting up a wireless network that were not
taken into account here. If research is continued, it would also be useful to
obtain a device designed specifically for measuring signal strength. This would
allow researchers to obtain more accurate data and therefore give better, more
accurate results. This research is a step in the right direction and is the beginning
of creating a useful tool for the IT professional
when designing a wireless network.
Vascular Smooth Muscle Cell Migration Modeling. MATTHEW
WOERNER (Tufts University, Medford, MA, 2155) JIM NUTARO (Oak Ridge National
Laboratory, Oak Ridge, TN, 37831)
The migration of vascular
smooth muscle cells is a catalyst for intimal hyperplasia, the thickening of
the arterial walls
in response to an injury in the blood vessel. Cell migration can be quantified
using Boyden Chamber experiments. A model by Jabbarzadeh and Abrams model is
used in designing this model. While this model
is based on Jabbarzadeh and Abram’s model, our model contains several differences.
In this algorithm, eukaryotic cells were modeled, instead of bacterial prokaryotic
cells in their model, which slightly changed the nature of how cells move. A
hybrid model, a model containing both discrete and continuous parts, was developed
to simulate Boyden Chamber experiments in order to better understand cell migration.
The hybrid nature of this model accounts for motion of individual cells, diffusion
of the chemoattractant, and the interaction between the chemoattractant and cells.
This model is being built using a C++ code and a discrete event system specification
(DEVS). In the future this model will provide the foundation to aid in predicting
the appearance of intimal hyperplasia following balloon angioplasty.
Vehicle Immobilization Technology Evaluation Project. JOSEPH
MASSIMINI (Purdue University, West Lafayette, In, 47906) GARY CAPPS (Oak
Ridge National Laboratory, Oak Ridge, TN, 37831)
Since September 11, 2001,
the Federal Motor Carrier Safety Administration (FMCSA) has been actively investigating
methods
to improve safety, security, and efficiency through the Hazardous Materials Safety
and Security Technology Operational Test. The purpose of that Operational Test
was to quantify the security costs and benefits of an operational concept that
applies technology and improved enforcement procedures to hazardous materials
(hazmat) transportation. In 2005, the House of Representatives Conference Report
108-792 stated that further testing of technologies, including vehicle immobilization
is necessary. The present Vehicle Immobilization Technology (VIT) Evaluation
Project has been conducted to support the Congressional directive, and has built
on the experience and lessons learned from previous field operational tests.
A VIT is any technology that prevents a highway vehicle from reaching its destination.
There are two types of VITs. Vehicle Disabling Technologies (VDTs) prevent the
motion of a stopped vehicle, and Vehicle Shutdown Technologies (VSTs) stop a
moving vehicle. These devices typically work through communication between a
dispatch office and the vehicle’s on-board computer system, and use GPS and/or
cellular technology. The VIT evaluation project used information from the FMCSA
Operational Test to compile a list of vendors of VIT technologies. As available,
companies provided ORNL public information that they had about their products
for review. Visits were conducted to selected companies in the United States.
In February 2007, six companies demonstrated their products to ORNL and members
of the federal government at Michelin North America’s Laurens Proving Grounds
near Laurens, South Carolina. A test track was used to allow moving vehicles
to be shutdown safely in a secured area. Test vehicles were outfitted with sensors
to collect kinematics data for evaluation. In March 2007, a workshop was held
at the annual Commercial Vehicle Safety Alliance (CVSA) conference in Atlanta,
Georgia where the use of VITs was discussed, and an open forum elicited input
from attendees. Information collected from these events were used to create a
report that contained best practices for hazmat carrier utilization and a concept
of operation for law enforcement so that the safety and efficiency of VIT usage
can be emphasized. The final report will be sent to Congress for their review
and further consideration.
Wireless Roadside Inspection Proof-of-Concept Test. MARY LASCURAIN
(Pensacola Christian College, Pensacola, FL, 32523) GARY CAPPS (Oak Ridge
National Laboratory, Oak Ridge, TN, 37831)
Safety inspections are performed
on
commercial vehicles to promote safety on the roadways, but these inspections
are limited due to their labor-intensive nature. The use of a wireless inspection
method could dramatically increase the number of safety inspections by allowing
enforcement personnel to check driver licensing, medical card, carrier, and weight
information without requiring the driver to stop. This proof-of-concept test
examines the feasibility, effectiveness, and limitations of the wireless inspection
method. PeopleNet, a producer of current electronic on-board recorder technology,
designed a system to produce a Safety Data Message Set (SDMS) containing the
desired information. This SDMS data was compared to similar data obtained through
an independent monitoring system comprised of an eDAQ-lite, VBOX III, Air-Weigh,
and custom software. The ability to send and receive an SDMS at varying truck
orientations (in 45-degree increments), distances (100 ft to 400 ft), and frequencies
(5.9 GHz and 2.4 GHz) was tested under static conditions. SDMS transmission from
the instrumented truck to a roadside unit and mobile enforcement vehicle (MEV)
was tested at various relative speeds in the dynamic portion of testing. Tests
were performed at 2.4 GHz as well as 5.9 GHz, and two different antenna types
(dome and stick) were used. Most of the test data for the SDMS files was accurate.
However, due to software problems in the PeopleNet system, over an hour was required
for some driver status changes to be reflected in the SDMS. The best reception
under static conditions was found to be to either side, slightly ahead of the
instrumented truck. Reception was best on the right side, where the antenna was
located. The dynamic tests indicated that the dome-type antenna had better reception
at 2.4 GHz, while the stick antenna performed better at 5.9 GHz. The use of a
tripod for the antenna mount increased the reception for both antennas. Files
were successfully transferred at various speeds (up to 55 mph). This proof-of-concept
test demonstrated the feasibility of a wireless inspection method while identifying
areas in which further testing would be beneficial. Further research should include
more extensive testing to determine ideal antenna height, the most appropriate
frequency, and the optimum mounting locations for both trucks and MEVs. Additionally,
the effects of terrain, other vehicle interference, and weather will need to
be well understood.
Zirconium Oxide Nanostructures Prepared by Anodic Oxidation. YING YI
DANG (Columbia University, New York, NY, 10027) M. PARANS PARANTHAMAN
(Oak Ridge National Laboratory, Oak Ridge, TN, 37831)
Zirconium oxide is an advanced
ceramic material highly useful for structural and electrical applications because
of its high strength, fracture toughness, chemical and thermal stability, and
biocompatibility. If highly-ordered porous zirconium oxide membranes can be
successfully formed, this will expand its real-world applications, such as
further enhancing solid-oxide fuel cell technology. Recent studies have achieved
various morphologies of porous zirconium oxide via anodization, but they have
yet to create a porous layer where nanoholes are formed in a highly ordered
array. In this study, electrochemical methods were used for zirconium oxide
synthesis due to its advantages over other kinds of coating techniques, and
because the thickness and morphology of the ceramic films can be easily tuned
by the electrochemical parameters, such as electrolyte solutions and processing
conditions, such as pH, voltage, and duration. The effects of additional steps
such as pre-annealing and post-annealing were also examined. Results demonstrate
the formation of anodic porous zirconium oxide with diverse morphologies, such
as sponge-like layers, porous arrays with nanoholes ranging from 40 to 75 nm,
and nanotube layers. X-ray powder diffraction analysis indicates a cubic crystallographic
structure in the zirconium oxide. It was noted that increased voltage improved
the ability of the membrane to stay adhered to the zirconium substrate, whereas
lower voltages caused a propensity for the oxide film to flake off. Further
studies are needed to control and confine these morphologies to specific parameter
windows, and to investigate other important characteristics
such as ionic conductivity.
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