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Journal of Undergraduate Research
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OIT Best Practices
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MUSC Environmental Biosciences Progress Report
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ARM Facilities Newsletter
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Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report
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System of systems modeling and analysis.
This report documents the results of an LDRD program entitled 'System of Systems Modeling and Analysis' that was conducted during FY 2003 and FY 2004. Systems that themselves consist of multiple systems (referred to here as System of Systems or SoS) introduce a level of complexity to systems performance analysis and optimization that is not readily addressable by existing capabilities. The objective of the 'System of Systems Modeling and Analysis' project was to develop an integrated modeling and simulation environment that addresses the complex SoS modeling and analysis needs. The approach to meeting this objective involved two key efforts. First, a static analysis approach, called state modeling, has been developed that is useful for analyzing the average performance of systems over defined use conditions. The state modeling capability supports analysis and optimization of multiple systems and multiple performance measures or measures of effectiveness. The second effort involves time simulation which represents every system in the simulation using an encapsulated state model (State Model Object or SMO). The time simulation can analyze any number of systems including cross-platform dependencies and a detailed treatment of the logistics required to support the systems in a defined mission.
Date:
January 1, 2005
Creator:
Campbell, James E.; Anderson, Dennis James; Longsine, Dennis E. & Shirah, Donald N.
Object Type:
Report
System:
The UNT Digital Library
Time Reversal Violation
This talk briefly reviews three types of time-asymmetry in physics, which I classify as universal, macroscopic and microscopic. Most of the talk is focused on the latter, namely the violation of T-reversal invariance in particle physics theories. In sum tests of microscopic T-invariance, or observations of its violation, are limited by the fact that, while we can measure many processes, only in very few cases can we construct a matched pair of process and inverse process and observe it with sufficient sensitivity to make a test. In both the cases discussed here we can achieve an observable T violation making use of flavor tagging, and in the second case also using the quantum properties of an antisymmetric coherent state of two B mesons to construct a CP-tag. Both these tagging properties depend only on very general properties of the flavor and/or CP quantum numbers and so provide model independent tests for T-invariance violations. The microscopic laws of physics are very close to T-symmetric. There are small effects that give CP- and T-violating processes in three-generation-probing weak decays. Where a T-violating observable can be constructed we see the relationships between T-violation and CP-violation expected in a CPT conserving theory. These microscopic …
Date:
January 27, 2009
Creator:
Quinn, H.
Object Type:
Article
System:
The UNT Digital Library
Future possibilities with Fermilab neutrino beams
We will start with a brief overview of neutrino oscillation physics with emphasis on the remaining unanswered questions. Next, after mentioning near future reactor and accelerator experiments searching for a non zero {theta}{sub 13}, we will introduce the plans for the next generation of long-baseline accelerator neutrino oscillation experiments. We will focus on experiments utilizing powerful (0.7-2.1 MW) Fermilab neutrino beams, either existing or in the design phase.
Date:
January 1, 2008
Creator:
Saoulidou, Niki
Object Type:
Article
System:
The UNT Digital Library
Status of Offshore Wind Energy Projects, Policies and Programs in the United States
This paper provides the status of the offshore wind energy project proposals in the United States and describes strategic issues faced by the U.S. wind industry.
Date:
January 1, 2008
Creator:
Musial, W. & Ram, B.
Object Type:
Article
System:
The UNT Digital Library
Theory and Fluid Simulations of Boundary Plasma Fluctuations
Theoretical and computational investigations are presented of boundary plasma microturbulence that take into account important effects of the geometry of diverted tokamaks--in particular, the effect of x-point magnetic shear and the termination of field lines on divertor plates. We first generalize our previous 'heuristic boundary condition' which describes, in a lumped model, the closure of currents in the vicinity of the x-point region to encompass three current-closure mechanisms. We then use this boundary condition to derive the dispersion relation for low-beta flute-like modes in the divertor-leg region under the combined drives of curvature, sheath impedance, and divertor tilt effects. The results indicate the possibility of strongly growing instabilities, driven by sheath boundary conditions, and localized in either the private or common flux region of the divertor leg depending on the radial tilt of divertor plates. We re-visit the issue of x-point effects on blobs, examining the transition from blobs terminated by x-point shear to blobs that extend over both the main SOL and divertor legs. We find that, for a main-SOL blob, this transition occurs without a free-acceleration period as previously thought, with x-point termination conditions applying until the blob has expanded to reach the divertor plate. We also derive …
Date:
January 9, 2007
Creator:
Cohen, R. H.; LaBombard, B.; LoDestro, L. L.; Rognlien, T. D.; Ryutov, D. D.; Terry, J. L. et al.
Object Type:
Article
System:
The UNT Digital Library
Coherent neutrino-nucleus scattering and the MINERvA experiment
In this paper we describe the capabilities of the MINERvA experiment for the measurement of neutrino-nucleus coherent scattering.
Date:
January 1, 2007
Creator:
Gallagher, H.; U., /Tufts; Harris, Deborah & /Fermilab
Object Type:
Article
System:
The UNT Digital Library
Primer: The DOE Wind Energy Program's Approach to Calculating Cost of Energy: July 9, 2005 - July 8, 2006
This report details the methodology used by DOE to calculate levelized cost of wind energy and demonstrates the variation in COE estimates due to different financing assumptions independent of wind generation technology.
Date:
January 1, 2008
Creator:
George, K. & Schweizer, T.
Object Type:
Report
System:
The UNT Digital Library
Summary of Workshop: Barriers to Energy Efficient Residential Ventilation
The objectives for this workshop were to bring together those with different viewpoints on the implementation of energy efficient ventilation in homes to share their perspectives. The primary benefit of the workshop is to allow the participants to get a broader understanding of the issues involved and thereby make themselves more able to achieve their own goals in this area. In order to achieve this objective each participant was asked to address four objectives from their point of view: (1) Drivers for energy efficient residential ventilation: Why is this an important issue? Who cares about it? Where is the demand: occupants, utilities, regulation, programs, etc? What does sustainability mean in this context? (2) Markets & Technologies: What products, services and systems are out there? What kinds of things are in the pipeline? What is being installed now? Are there regional or other trends? What are the technology interactions with other equipment and the envelope? (3) Barriers to Implementation: What is stopping decision makers from implementing energy-efficient residential ventilation systems? What kind of barriers are there: technological, cost, informational, structural, etc. What is the critical path? (4) Solutions: What can be done to overcome the barriers and how can/should we do …
Date:
January 10, 2008
Creator:
Sherman, Max & Sherman, Max
Object Type:
Report
System:
The UNT Digital Library
Clean Cities Now, Vol. 12, No. 1 - January 2008
This quarterly Web-based newsletter features articles relating to alternative fuel and advanced technology vehicles, idle reduction technologies, and fuel economy measures.
Date:
January 1, 2008
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Characterization of Turbiditic Oil Reservoirs Based on Geophysical Models of their Formation
Models are developed and solved to describe the flow of and deposition from low and high concentration turbidity currents. The shallow water equations are amended to include particle transport to describe the low concentration turbidity currents. The suspension balance model is used to describe the high concentration turbidity currents. Numerical simulations are developed to solve the highly non-linear, free boundary problems associated with these models. Simpler, algebraic scaling relationships are also developed for these models. The models are successfully validated against field observations of turbidites. With these models, one can take seismic information on the shape of the turbiditic deposit and estimate the particle size, which can be used to determine the porosity and permeability.
Date:
January 15, 2006
Creator:
Bonnecaze, Roger
Object Type:
Report
System:
The UNT Digital Library
Measurement of the t anti-t production cross section and top quark mass extraction using dilepton events in p anti-p collisions
We present a measurement of the top quark pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using approximately 1 fb{sup -1} of data collected with the D0 detector. We consider decay channels containing two high p{sub T} charged leptons where one lepton is identified as an electron or a muon while the other lepton can be an electron, a muon or a hadronically decaying {tau} lepton. For a mass of the top quark of 170 GeV, the measured cross section is 7.5{sub -1.0}{sup +1.0}(stat){sub -0.06}{sup +0.7}(syst){sub -0.5}{sup 0.6}(lumi) pb. Using {ell}{sub {tau}} events only, they measure: {sigma}{sub t{bar t}} x B(t{bar t} {yields} {ell}{sub {tau}}b{bar b}) = 0.13{sub -0.08}{sup +0.09}(stat){sub -0.06}{sup 0.06}(syst)+{sub -0.02}{sup +0.02}(lumi) pb. Comparing the measured cross section as a function of the mass of the top quark with a partial next-to-next-to leading order Quantum Chromodynamics theoretical prediction, we extract a mass of the top quark of 171.5{sub -8.8}{sup +9.9} GeV, in agreement with direct measurements.
Date:
January 1, 2009
Creator:
Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Strategies for the Commercialization and Deployment of Greenhouse Gas Intensity-Reducing Technologies and Practices
New technologies will be a critical component--perhaps the critical component--of our efforts to tackle the related challenges of energy security, climate change, and air pollution, all the while maintaining a strong economy. But just developing new technologies is not enough. Our ability to accelerate the market penetration of clean energy, enabling, and other climate-related technologies will have a determining impact on our ability to slow, stop, and reverse the growth in greenhouse gas (GHG) emissions. Title XVI, Subtitle A, of the Energy Policy Act of 2005 (EPAct 2005) directs the Administration to report on its strategy to promote the commercialization and deployment (C&D) of GHG intensity-reducing technologies and practices. The Act also requests the Administration to prepare an inventory of climate-friendly technologies suitable for deployment and to identify the barriers and commercial risks facing advanced technologies. Because these issues are related, they are integrated here within a single report that we, representing the Committee on Climate Change Science and Technology Integration (CCCSTI), are pleased to provide the President, the Congress, and the public. Over the past eight years, the Administration of President George W. Bush has pursued a series of policies and measures aimed at encouraging the development and deployment …
Date:
January 2009
Creator:
Committee on Climate Change Science and Technology Integration
Object Type:
Report
System:
The UNT Digital Library
High Resolution Simulation of Beam Dynamics in Electron Linacs for Free Electron Lasers
In this paper we report on large scale multi-physics simulation of beam dynamics in electron linacs for next generation free electron lasers (FELs). We describe key features of a parallel macroparticle simulation code including three-dimensional (3D) space-charge effects, short-range structure wake fields, longitudinal coherent synchrotron radiation (CSR) wake fields, and treatment of radiofrequency (RF) accelerating cavities using maps obtained from axial field profiles. A macroparticle up-sampling scheme is described that reduces the shot noise from an initial distribution with a smaller number of macroparticles while maintaining the global properties of the original distribution. We present a study of the microbunching instability which is a critical issue for future FELs due to its impact on beam quality at the end of the linac. Using parameters of a planned FEL linac at Lawrence Berkeley National Laboratory (LBNL), we show that a large number of macroparticles (beyond 100 million) is needed to control numerical shot noise that drives the microbunching instability. We also explore the effect of the longitudinal grid on simulation results. We show that acceptable results are obtained with around 2048 longitudinal grid points, and we discuss this in view of the spectral growth rate predicted from linear theory. As an …
Date:
January 5, 2009
Creator:
Ryne, R.D.; Venturini, M.; Zholents, A.A. & Qiang, J.
Object Type:
Article
System:
The UNT Digital Library
Assessment of Unabated Facility Emission Potentials for Evaluating Airborne Radionuclide Monitoring Requirements at Pacific Northwest National Laboratory - 2007
Assessments were performed to evaluate compliance with the airborne radionuclide emission monitoring requirements in the National Emission Standards for Hazardous Air Pollutants (NESHAP – U.S. Code of Federal Regulations, Title 40, Part 61, Subpart H) and Washington Administrative Code (WAC) 246-247: Radiation Protection – Air Emissions. In these NESHAP assessments, potential unabated offsite doses were evaluated for emission locations at buildings that are part of the consolidated laboratory campus of the Pacific Northwest National Laboratory. This report describes the inventory-based methods and provides the results for the NESHAP assessment performed in 2007.
Date:
January 1, 2008
Creator:
Ballinger, Marcel Y.; Barfuss, Brad C. & Gervais, Todd L.
Object Type:
Report
System:
The UNT Digital Library
CHANGING THE SAFETY CULTURE IN HANFORD TANK FARMS
In 2000 the Hanford Tank Farms had one of the worst safety records in the Department of Energy Complex. By the end of FY08 the safety performance of the workforce had turned completely around, resulting in one of the best safety records in the DOE complex for operations of its kind. This paper describes the variety of programs and changes that were put in place to accomplish such a dramatic turn-around. The U.S. Department of Energy's 586-square-mile Hanford Site in Washington State was established during World War II as part of the Manhattan Project to develop nuclear materials to end the war. For the next several decades it continued to produce plutonium for the nation's defense, leaving behind vast quantities of radioactive and chemical waste. Much of this waste, 53,000,000 gallons, remains stored in 149 aging single-shell tanks and 28 newer double-shell tanks. One of the primary objectives at Hanford is to safely manage this waste until it can be prepared for disposal, but this has not always been easy. These giant underground tanks, many of which date back to the beginning of the Manhattan Project, range in size from 55,000 gallons up to 1.1 million gallons, and are buried …
Date:
January 6, 2009
Creator:
MV, BERRIOCHOA & LJ, ALCALA
Object Type:
Article
System:
The UNT Digital Library
Theoretical Studies of Nucleation Kinetics and Nanodroplet Microstructure
The goals of this project were to (1) explore ways of bridging the gap between fundamental molecular nucleation theories and phenomenological approaches based on thermodynamic reasoning, (2) test and improve binary nucleation theory, and (3) provide the theoretical underpinning for a powerful new experimental technique, small angle neutron scattering (SANS) from nanodroplet aerosols, that can probe the compositional structure of nanodroplets. This report summarizes the accomplishments of this project in realizing these goals. Publications supported by this project fall into three general categories: (1) theoretical work on nucleation theory (2) experiments and modeling of nucleation and condensation in supersonic nozzles, and (3) experimental and theoretical work on nanodroplet structure and neutron scattering. These publications are listed and briefly summarized in this report.
Date:
January 31, 2009
Creator:
Wilemski, Gerald
Object Type:
Report
System:
The UNT Digital Library
External Second Gate-Fourier Transform Ion Mobility Spectrometry.
Ion mobility spectrometry (IMS) is recognized as one of the most sensitive and versatile techniques for the detection of trace levels of organic vapors. IMS is widely used for detecting contraband narcotics, explosives, toxic industrial compounds and chemical warfare agents. Increasing threat of terrorist attacks, the proliferation of narcotics, Chemical Weapons Convention treaty verification as well as humanitarian de-mining efforts has mandated that equal importance be placed on the analysis time as well as the quality of the analytical data. (1) IMS is unrivaled when both speed of response and sensitivity has to be considered. (2) With conventional (signal averaging) IMS systems the number of available ions contributing to the measured signal to less than 1%. Furthermore, the signal averaging process incorporates scan-to-scan variations decreasing resolution. With external second gate Fourier Transform ion mobility spectrometry (FT-IMS), the entrance gate frequency is variable and can be altered in conjunction with other data acquisition parameters to increase the spectral resolution. The FT-IMS entrance gate operates with a 50% duty cycle and so affords a 7 to 10-fold increase in sensitivity. Recent data on high explosives are presented to demonstrate the parametric optimization in sensitivity and resolution of our system.
Date:
January 1, 2005
Creator:
Tarver, Edward E., III
Object Type:
Report
System:
The UNT Digital Library
Optimal flux patterns in cellular metabolic networks
The availability of whole-cell level metabolic networks of high quality has made it possible to develop a predictive understanding of bacterial metabolism. Using the optimization framework of flux balance analysis, I investigate metabolic response and activity patterns to variations in the availability of nutrient and chemical factors such as oxygen and ammonia by simulating 30,000 random cellular environments. The distribution of reaction fluxes is heavy-tailed for the bacteria H. pylori and E. coli, and the eukaryote S. cerevisiae. While the majority of flux balance investigations have relied on implementations of the simplex method, it is necessary to use interior-point optimization algorithms to adequately characterize the full range of activity patterns on metabolic networks. The interior-point activity pattern is bimodal for E. coli and S. cerevisiae, suggesting that most metabolic reaction are either in frequent use or are rarely active. The trimodal activity pattern of H. pylori indicates that a group of its metabolic reactions (20%) are active in approximately half of the simulated environments. Constructing the high-flux backbone of the network for every environment, there is a clear trend that the more frequently a reaction is active, the more likely it is a part of the backbone. Finally, I briefly …
Date:
January 20, 2007
Creator:
Almaas, E
Object Type:
Article
System:
The UNT Digital Library
Own Your Power! A Consumer Guide to Solar Electricity for the Home (Brochure)
A consumer guide about solar electricity for the home. Includes information about types of solar electric systems, how to choose a system, financing, and costs.
Date:
January 1, 2009
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Y-12 Groundwater Protection Program Groundwater and Surface water Sampling and Analysis Plan for Calendar Year 2006
This plan provides a description of the groundwater and surface water quality monitoring activities planned for calendar year (CY) 2006 at the U.S. Department of Energy (DOE) Y-12 National Security Complex (Y-12) that will be managed by the Y-12 Groundwater Protection Program (GWPP). Groundwater and surface water monitoring performed by the GWPP during CY 2006 will be in accordance with DOE Order 540.1 requirements and the following goals: {sm_bullet} to maintain surveillance of existing and potential groundwater contamination sources; {sm_bullet} to provide for the early detection of groundwater contamination and determine the quality of groundwater and surface water where contaminants are most likely to migrate beyond the Oak Ridge Reservation property line; {sm_bullet} to identify and characterize long-term trends in groundwater quality at Y-12; and ! to provide data to support decisions concerning the management and protection of groundwater resources. Groundwater and surface water monitoring during CY 2006 will be performed primarily in three hydrogeologic regimes at Y-12: the Bear Creek Hydrogeologic Regime (Bear Creek Regime), the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime), and the Chestnut Ridge Hydrogeologic Regime (Chestnut Ridge Regime). The Bear Creek and East Fork regimes are located in Bear Creek Valley, and …
Date:
January 1, 2006
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Dose dependent effects of exercise training and detraining ontotal and regional adiposity in 4,663 men and 1,743
Objective: To determine if exercise reduces body weight andto examine the dose-response relationships between changes in exerciseand changes in total and regional adiposity. Methods and Results:Questionnaires on weekly running distance and adiposity from a largeprospective study of 3,973 men and 1,444 women who quit running(detraining), 270 men and 146 women who started running (training) and420 men and 153 women who remained sedentary during 7.4 years offollow-up. There were significant inverse relationships between change inthe amount of vigorous exercise (km/wk run) and changes in weight and BMIin men (slope+-SE:-0.039+-0.005 kg and -0.012+-0.002 kg/m2 per km/wk,respectively) and older women (-0.060+-0.018 kg and -0.022+-0.007 kg/m2per km/wk) who quit running, and in initially sedentary men(-0.098+-0.017 kg and -0.032+-0.005 kg/m2 per km/wk) and women(-0.062+-0.023 kg and -0.021+-0.008 kg/m2 per km/wk) who started running.Changes in waist circumference were also inversely related to changes inrunning distance in men who quit (-0.026+-0.005 cm per km/wk) or startedrunning (-0.078+-0.017 cm per km/wk). Conclusions. The initiation andcessation of vigorous exercise decrease and increase body weight andintra-abdominal fat, respectively, and these changes are proportional tothe change in exercise dose.
Date:
January 6, 2006
Creator:
Williams, Paul T. & Thompson, Paul D.
Object Type:
Article
System:
The UNT Digital Library
Characterization and Analysis of CIGS and CdTE Solar Cells: December 2004 - July 2008
The work reported here embodies a device-physics approach based on careful measurement and interpretation of data from CIGS and CdTe solar cells.
Date:
January 1, 2009
Creator:
Sites, J. R.
Object Type:
Report
System:
The UNT Digital Library
Metastable Solid Solution Phases in the LiFePO4/FePO4 System
None
Date:
January 2, 2006
Creator:
Chen, Guoying Chen; Song, Xiangyun & Richardson, Thomas J.
Object Type:
Article
System:
The UNT Digital Library
Revised plan : recommended investigation at Navarre, Kansas.
None
Date:
January 31, 2006
Creator:
LaFreniere, L. M.
Object Type:
Report
System:
The UNT Digital Library