Degree Discipline

Degree Level

Month

228 Matching Results

Results open in a new window/tab.

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV using kinematic characteristics of lepton + jets events (open access)

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV using kinematic characteristics of lepton + jets events

We present a measurement of the top quark pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV utilizing 425 pb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron Collider. We consider the final state of the top quark pair containing one high-p{sub T} electron or muon and at least four jets. We exploit specific kinematic features of t{bar t} events to extract the cross section. For a top quark mass of 175 GeV, we measure {sigma}{sub t{bar t}} = 6.4{sub -1.2}{sup +1.3}(stat) {+-} 0.7(syst) {+-} 0.4(lum)pb, in good agreement with the standard model prediction.
Date: May 1, 2007
Creator: Abazov, V.
Object Type: Article
System: The UNT Digital Library
Observation and Properties of L = 1 B(1) and B*(2) Mesons (open access)

Observation and Properties of L = 1 B(1) and B*(2) Mesons

None
Date: May 1, 2007
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
Search for stopped gluinos from p-anti-p collisions at s**(1/2) = 1.96-TeV (open access)

Search for stopped gluinos from p-anti-p collisions at s**(1/2) = 1.96-TeV

Long-lived, heavy particles are predicted in a number of models beyond the standard model of particle physics. We present the first direct search for such particles' decays, occurring up to 100 h after their production and not synchronized with an accelerator bunch crossing. We apply the analysis to the gluino ({tilde g}), predicted in split supersymmetry, which after hadronization can become charged and lose enough momentum through ionization to come to rest in dense particle detectors. Approximately 410 pb{sup -1} of p{bar p} collisions at sqrt(s)=1.96 TeV collected with the D0 detector during Run II of the Fermilab Tevatron collider are analyzed in search of such 'stopped gluinos' decaying into a gluon and a neutralino ({tilde {chi}}{sub 1}{sup 0}). Limits are placed on the (gluino cross section)x(probability to stop)x[BR({tilde g}{yields}g {tilde {chi}}{sub 1}{sup 0<})] as a function of the gluino and {tilde {chi}}{sub 1}{sup 0<} masses, for gluino lifetimes from 30 {micro}s-100 h.
Date: May 1, 2007
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
Z gamma production and limits on anomalous Z Z gamma and Z gamma gamma couplings in panti-p collisions at s**(1/2) = 1.96- TeV (open access)

Z gamma production and limits on anomalous Z Z gamma and Z gamma gamma couplings in panti-p collisions at s**(1/2) = 1.96- TeV

None
Date: May 1, 2007
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
First observation of K(L) ---> pi+- e-+ nu e+ e- (open access)

First observation of K(L) ---> pi+- e-+ nu e+ e-

None
Date: May 1, 2007
Creator: Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Blucher, E.; Bock, G. J. et al.
Object Type: Article
System: The UNT Digital Library
Searches for new phenomena with lepton final states at the Tevatron (open access)

Searches for new phenomena with lepton final states at the Tevatron

Numerous searches for new phenomena have been carried out using data from proton-antiproton collisions at Fermilab's Tevatron. Final states with leptons give signatures which are relatively unique and generally have small backgrounds. We present many of the latest results from the CDF and D0 collaborations from 0.4-1.2 fb{sup -1} of data. Topics include supersymmetry, extra gauge bosons, Randall-Sundrum gravitons, excited electrons and neutral, long-lived particles.
Date: May 1, 2007
Creator: Adams, T.
Object Type: Article
System: The UNT Digital Library
Measurement of the atmospheric muon charge ratio at TeV energies with MINOS (open access)

Measurement of the atmospheric muon charge ratio at TeV energies with MINOS

The 5.4 kton MINOS far detector has been taking charge-separated cosmic ray muon data since the beginning of August, 2003 at a depth of 2070 m.w.e. in the Soudan Underground Laboratory, Minnesota, USA. The data with both forward and reversed magnetic field running configurations were combined to minimize systematic errors in the determination of the underground muon charge ratio. When averaged, two independent analyses find the charge ratio underground to be N{sub {mu}}+/N{sub {mu}}-=1.374{+-}0.004(stat)-0.010{sup +0.012}(sys). Using the map of the Soudan rock overburden, the muon momenta as measured underground were projected to the corresponding values at the surface in the energy range 1-7 TeV. Within this range of energies at the surface, the MINOS data are consistent with the charge ratio being energy independent at the 2 standard deviation level. When the MINOS results are compared with measurements at lower energies, a clear rise in the charge ratio in the energy range 0.3-1.0 TeV is apparent. A qualitative model shows that the rise is consistent with an increasing contribution of kaon decays to the muon charge ratio.
Date: May 1, 2007
Creator: Adamson, P.; Andreopoulos, C.; Arms, K.E.; Armstrong, R.; Auty, D.J.; Avvakumov, S. et al.
Object Type: Article
System: The UNT Digital Library
2006 B100 Quality Survey Results: Milestone Report (open access)

2006 B100 Quality Survey Results: Milestone Report

In 2006, the National Renewable Energy Laboratory conducted a nationwide quality survey of pure biodiesel (B100) intended to be used as a blendstock. The study collected random samples throughout the United States and analyzed them for quality against the current and proposed ASTM D6751 fuel quality specifications.
Date: May 1, 2007
Creator: Alleman, T. L.; McCormick, R. L. & Deutch, S.
Object Type: Report
System: The UNT Digital Library
Current Renewable Energy Technologies and Future Projections (open access)

Current Renewable Energy Technologies and Future Projections

The generally acknowledged sources of renewable energy are wind, geothermal, biomass, solar, hydropower, and hydrogen. Renewable energy technologies are crucial to the production and utilization of energy from these regenerative and virtually inexhaustible sources. Furthermore, renewable energy technologies provide benefits beyond the establishment of sustainable energy resources. For example, these technologies produce negligible amounts of greenhouse gases and other pollutants in providing energy, and they exploit domestically available energy sources, thereby reducing our dependence on both the importation of fossil fuels and the use of nuclear fuels. The market price of renewable energy technologies does not reflect the economic value of these added benefits.
Date: May 1, 2007
Creator: Allison, Stephen W.; Lapsa, Melissa Voss; Ward, Christina D.; Smith, Barton; Grubb, Kimberly R. & Lee, Russell
Object Type: Report
System: The UNT Digital Library
Final Technical Report: Development of the DUSTRAN GIS-Based Complex Terrain Model for Atmospheric Dust Dispersion (open access)

Final Technical Report: Development of the DUSTRAN GIS-Based Complex Terrain Model for Atmospheric Dust Dispersion

Activities at U.S. Department of Defense (DoD) training and testing ranges can be sources of dust in local and regional airsheds governed by air-quality regulations. The U.S. Department of Energy’s Pacific Northwest National Laboratory just completed a multi-year project to develop a fully tested and documented atmospheric dispersion modeling system (DUST TRANsport or DUSTRAN) to assist the DoD in addressing particulate air-quality issues at military training and testing ranges.
Date: May 1, 2007
Creator: Allwine, K Jerry; Rutz, Frederick C.; Shaw, William J.; Rishel, Jeremy P.; Fritz, Brad G.; Chapman, Elaine G. et al.
Object Type: Report
System: The UNT Digital Library
House and Senate Chaplains (open access)

House and Senate Chaplains

None
Date: May 1, 2007
Creator: Amer, Mildred
Object Type: Report
System: The UNT Digital Library
Microsecond delays on non-real time operating systems (open access)

Microsecond delays on non-real time operating systems

We have developed microsecond timing and profiling software that runs on standard Windows and Linux based operating systems. This software is orders of magnitudes better than most of the standard native functions in wide use. Our software libraries calibrate RDTSC in microseconds or seconds to provide two different types of delays: a ''Guaranteed Minimum'' and a precision ''Long Delay'', which releases to the kernel. Both return profiling information of the actual delay.
Date: May 1, 2007
Creator: Angstadt, R.; Estrada, J.; Diehl, H. T.; Flaugher, B. & Johnson, M.
Object Type: Article
System: The UNT Digital Library
FUNDAMENTAL SAFETY TESTING AND ANALYSIS OF HYDROGEN STORAGE MATERIALS AND SYSTEMS (open access)

FUNDAMENTAL SAFETY TESTING AND ANALYSIS OF HYDROGEN STORAGE MATERIALS AND SYSTEMS

Hydrogen is seen as the future automobile energy storage media due to its inherent cleanliness upon oxidation and its ready utilization in fuel cell applications. Its physical storage in light weight, low volume systems is a key technical requirement. In searching for ever higher gravimetric and volumetric density hydrogen storage materials and systems, it is inevitable that higher energy density materials will be studied and used. To make safe and commercially acceptable systems, it is important to understand quantitatively, the risks involved in using and handling these materials and to develop appropriate risk mitigation strategies to handle unforeseen accidental events. To evaluate these materials and systems, an IPHE sanctioned program was initiated in 2006 partnering laboratories from Europe, North America and Japan. The objective of this international program is to understanding the physical risks involved in synthesis, handling and utilization of solid state hydrogen storage materials and to develop methods to mitigate these risks. This understanding will support ultimate acceptance of commercially high density hydrogen storage system designs. An overview of the approaches to be taken to achieve this objective will be given. Initial experimental results will be presented on environmental exposure of NaAlH{sub 4}, a candidate high density hydrogen …
Date: May 1, 2007
Creator: Anton, D
Object Type: Article
System: The UNT Digital Library
Arsenic pilot plant operation and results:Weatherford, Oklahoma. (open access)

Arsenic pilot plant operation and results:Weatherford, Oklahoma.

Narasimhan Consulting Services, Inc. (NCS), under a contract with the Sandia National Laboratories (SNL), designed and operated pilot scale evaluations of the adsorption and coagulation/filtration treatment technologies aimed at meeting the recently revised arsenic maximum contaminant level (MCL) for drinking water. The standard of 10 {micro}g/L (10 ppb) is effective as of January 2006. The pilot demonstration is a project of the Arsenic Water Technology Partnership program, a partnership between the American Water Works Association Research Foundation (AwwaRF), SNL and WERC (A Consortium for Environmental Education and Technology Development). The pilot evaluation was conducted at Well 30 of the City of Weatherford, OK, which supplies drinking water to a population of more than 10,400. Well water contained arsenic in the range of 16 to 29 ppb during the study. Four commercially available adsorption media were evaluated side by side for a period of three months. Both adsorption and coagulation/filtration effectively reduced arsenic from Well No.30. A preliminary economic analysis indicated that adsorption using an iron oxide media was more cost effective than the coagulation/ filtration technology.
Date: May 1, 2007
Creator: Aragon, Malynda Jo; Arora, H. (Narasimhan Consulting Services Inc., Phoenix, Arizona); Karori, Saqib (Narasimhan Consulting Services Inc., Phoenix, Arizona) & Pathan, Sakib (Narasimhan Consulting Services Inc., Phoenix, Arizona)
Object Type: Report
System: The UNT Digital Library
Arsenic pilot plant operation and results - Socorro Springs, New Mexico - phase 1. (open access)

Arsenic pilot plant operation and results - Socorro Springs, New Mexico - phase 1.

Sandia National Laboratories (SNL) is conducting pilot scale evaluations of the performance and cost of innovative water treatment technologies aimed at meeting the recently revised arsenic maximum contaminant level (MCL) for drinking water. The standard of 10 {micro}g/L (10 ppb) is effective as of January 2006. The first pilot tests have been conducted in New Mexico where over 90 sites that exceed the new MCL have been identified by the New Mexico Environment Department. The pilot test described in this report was conducted in Socorro New Mexico between January 2005 and July 2005. The pilot demonstration is a project of the Arsenic Water Technology Partnership program, a partnership between the American Water Works Association Research Foundation (AwwaRF), SNL and WERC (A Consortium for Environmental Education and Technology Development). The Sandia National Laboratories pilot demonstration at the Socorro Springs site obtained arsenic removal performance data for five different adsorptive media under constant ambient flow conditions. Well water at Socorro Springs has approximately 42 ppb arsenic in the oxidized (arsenate-As(V)) redox state with moderate amounts of silica, low concentrations of iron and manganese and a slightly alkaline pH (8). The study provides estimates of the capacity (bed volumes until breakthrough at 10 …
Date: May 1, 2007
Creator: Aragon, Malynda Jo; Everett, Randy L.; Siegel, Malcolm Dean; Kottenstette, Richard Joseph; Holub, William E. Jr; Wright, Jeremy B. et al.
Object Type: Report
System: The UNT Digital Library
Cross-language information retrieval using PARAFAC2. (open access)

Cross-language information retrieval using PARAFAC2.

A standard approach to cross-language information retrieval (CLIR) uses Latent Semantic Analysis (LSA) in conjunction with a multilingual parallel aligned corpus. This approach has been shown to be successful in identifying similar documents across languages - or more precisely, retrieving the most similar document in one language to a query in another language. However, the approach has severe drawbacks when applied to a related task, that of clustering documents 'language-independently', so that documents about similar topics end up closest to one another in the semantic space regardless of their language. The problem is that documents are generally more similar to other documents in the same language than they are to documents in a different language, but on the same topic. As a result, when using multilingual LSA, documents will in practice cluster by language, not by topic. We propose a novel application of PARAFAC2 (which is a variant of PARAFAC, a multi-way generalization of the singular value decomposition [SVD]) to overcome this problem. Instead of forming a single multilingual term-by-document matrix which, under LSA, is subjected to SVD, we form an irregular three-way array, each slice of which is a separate term-by-document matrix for a single language in the parallel …
Date: May 1, 2007
Creator: Bader, Brett William; Chew, Peter; Abdelali, Ahmed (New Mexico State University, Las Cruces, NM) & Kolda, Tamara Gibson
Object Type: Report
System: The UNT Digital Library
Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 24, No. 4, Ed. 1 Tuesday, May 1, 2007 (open access)

Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 24, No. 4, Ed. 1 Tuesday, May 1, 2007

Monthly periodical from Oklahoma City, Oklahoma published by and for members of the Oklahoma State Firefighters Association that includes news and information along with advertising.
Date: May 1, 2007
Creator: Bain, Chris
Object Type: Journal/Magazine/Newsletter
System: The Gateway to Oklahoma History
Integrated Heat Pump HVAC Systems for Near-Zero-Energy Homes - Business Case Assessment (open access)

Integrated Heat Pump HVAC Systems for Near-Zero-Energy Homes - Business Case Assessment

The long range strategic goal of the Department of Energy's Building Technologies (DOE/BT) Program is to create, by 2020, technologies and design approaches that enable the construction of net-zero energy homes at low incremental cost (DOE/BT 2005). A net zero energy home (NZEH) is a residential building with greatly reduced needs for energy through efficiency gains, with the balance of energy needs supplied by renewable technologies. While initially focused on new construction, these technologies and design approaches are intended to have application to buildings constructed before 2020 as well resulting in substantial reduction in energy use for all building types and ages. DOE/BT's Emerging Technologies (ET) team is working to support this strategic goal by identifying and developing advanced heating, ventilating, air-conditioning, and water heating (HVAC/WH) technology options applicable to NZEHs. Although the energy efficiency of heating, ventilating, and air-conditioning (HVAC) equipment has increased substantially in recent years, new approaches are needed to continue this trend. Dramatic efficiency improvements are necessary to enable progress toward the NZEH goals, and will require a radical rethinking of opportunities to improve system performance. The large reductions in HVAC energy consumption necessary to support the NZEH goals require a systems-oriented analysis approach that characterizes …
Date: May 1, 2007
Creator: Baxter, Van D
Object Type: Report
System: The UNT Digital Library
The Forensic Evaluation of Fracture Marks: A Validation and Experimental Study. (open access)

The Forensic Evaluation of Fracture Marks: A Validation and Experimental Study.

Honors thesis written by a student in the UNT Honors College discussing the examination of fracture marks in forensic investigations in order to determine if two parts of an object belonged to a whole.
Date: May 1, 2007
Creator: Bethune, Sherry
Object Type: Thesis or Dissertation
System: The UNT Digital Library

NREL Research as Part of the Hydrogen Sorption Center of Excellence

None
Date: May 1, 2007
Creator: Blackburn, J. L.; Curtis, C. J.; Dillon, A. C.; Engtrakul, C.; Gennett, T.; Heben, M. J. et al.
Object Type: Presentation
System: The UNT Digital Library
Error Estimates Derived from the Data for Least-Squares Spline Fitting (open access)

Error Estimates Derived from the Data for Least-Squares Spline Fitting

None
Date: May 1, 2007
Creator: Blair, Jerome
Object Type: Article
System: The UNT Digital Library
CRISPR Recognition Tool (CRT): a tool for automatic detection of clustered regularly interspaced palindromic repeats (open access)

CRISPR Recognition Tool (CRT): a tool for automatic detection of clustered regularly interspaced palindromic repeats

Clustered Regularly Interspaced Palindromic Repeats (CRISPRs) are a novel type of direct repeat found in a wide range of bacteria and archaea. CRISPRs are beginning to attract attention because of their proposed mechanism; that is, defending their hosts against invading extrachromosomal elements such as viruses. Existing repeat detection tools do a poor job of identifying CRISPRs due to the presence of unique spacer sequences separating the repeats. In this study, a new tool, CRT, is introduced that rapidly and accurately identifies CRISPRs in large DNA strings, such as genomes and metagenomes. CRT was compared to CRISPR detection tools, Patscan and Pilercr. In terms of correctness, CRT was shown to be very reliable, demonstrating significant improvements over Patscan for measures precision, recall and quality. When compared to Pilercr, CRT showed improved performance for recall and quality. In terms of speed, CRT also demonstrated superior performance, especially for genomes containing large numbers of repeats. In this paper a new tool was introduced for the automatic detection of CRISPR elements. This tool, CRT, was shown to be a significant improvement over the current techniques for CRISPR identification. CRT's approach to detecting repetitive sequences is straightforward. It uses a simple sequential scan of a …
Date: May 1, 2007
Creator: Bland, Charles; Ramsey, Teresa L.; Sabree, Fareedah; Lowe, Micheal; Brown, Kyndall; Kyrpides, Nikos C. et al.
Object Type: Article
System: The UNT Digital Library
Field Testing of a Wet FGD Additive for Enhanced Mercury Control - Task 3 Full-scale Test Results (open access)

Field Testing of a Wet FGD Additive for Enhanced Mercury Control - Task 3 Full-scale Test Results

This Topical Report summarizes progress on Cooperative Agreement DE-FC26-04NT42309, 'Field Testing of a Wet FGD Additive'. The objective of the project is to demonstrate the use of a flue gas desulfurization (FGD) additive, Degussa Corporation's TMT-15, to prevent the reemission of elemental mercury (Hg{sup 0}) in flue gas exiting wet FGD systems on coal-fired boilers. Furthermore, the project intends to demonstrate whether the additive can be used to precipitate most of the mercury (Hg) removed in the wet FGD system as a fine TMT salt that can be separated from the FGD liquor and bulk solid byproducts for separate disposal. The project is conducting pilot- and full-scale tests of the TMT-15 additive in wet FGD absorbers. The tests are intended to determine required additive dosages to prevent Hg{sup 0} reemissions and to separate mercury from the normal FGD byproducts for three coal types: Texas lignite/Power River Basin (PRB) coal blend, high-sulfur Eastern bituminous coal, and low-sulfur Eastern bituminous coal. The project team consists of URS Group, Inc., EPRI, TXU Generation Company LP, Southern Company, and Degussa Corporation. TXU Generation has provided the Texas lignite/PRB cofired test site for pilot FGD tests, Monticello Steam Electric Station Unit 3. Southern Company is …
Date: May 1, 2007
Creator: Blythe, Gary
Object Type: Report
System: The UNT Digital Library
Technical Basis Document: A Statistical Basis for Interpreting Urinary Excretion of Plutonium Based on Accelerator Mass Spectrometry (AMS) for Selected Atoll Populations in the Marshall Islands (open access)

Technical Basis Document: A Statistical Basis for Interpreting Urinary Excretion of Plutonium Based on Accelerator Mass Spectrometry (AMS) for Selected Atoll Populations in the Marshall Islands

We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from <1 to 8 {micro}Bq per day and are well below action levels established under the latest Department regulation 10 CFR 835 in the United States for in vitro bioassay monitoring of {sup 239}Pu. However, our statistical analyses show that urinary excretion of plutonium-239 ({sup 239}Pu) from both cohort groups is significantly positively associated with volunteer age, especially for the resident population living on Enewetak Atoll. Urinary excretion of {sup 239}Pu from the Enewetak cohort was also found to be positively associated with estimates of cumulative exposure to worldwide fallout. Consequently, the age-related trends in urinary excretion of plutonium from Marshallese populations can be described by either a long-term component from residual systemic burdens acquired from previous exposures to worldwide fallout or a prompt (and eventual long-term) component acquired from low-level systemic intakes of plutonium associated with resettlement of the northern Marshall Islands, or some combination of both.
Date: May 1, 2007
Creator: Bogen, K; Hamilton, T F; Brown, T A; Martinelli, R E; Marchetti, A A; Kehl, S R et al.
Object Type: Report
System: The UNT Digital Library