Collection
Office of Scientific & Technical Information Technical Reports
2,262
Texas Laws and Resolutions Archive
844
Congressional Research Service Reports
800
Defense Base Closure and Realignment Commission
467
Government Accountability Office Reports
457
Texas Attorney General Opinions
39
Texas Register
16
Texas State Publications
14
End of Term Publications
4
Federal Register
3
3 More
Serial/Series Title
80th Legislature of Texas
818
2005 BRAC Commission
467
Senate Bills
391
House Bills
360
House Concurrent Resolutions
72
CRS Issue Briefs
60
78th Legislature of Texas
22
Senate Concurrent Resolutions
21
109th Congress
17
Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report
16
77 More
Country
States
Decade
Month
Day
Language
4,910 Matching Results
Results open in a new window/tab.
Measurements of Branching Fractions for B+ -> rho+ gamma, B0 -> rho0 gamma, and B0 -> omega gamma
The authors present branching fraction measurements for the radiative decays B{sup +} {yields} {rho}{sup +}{gamma}, B{sup 0} {yields} {rho}{sup 0}{gamma}, and B{sup 0} {yields} {omega}{gamma}. The analysis is based on a data sample of 465 million B{bar B} events collected with the BABAR detector at the PEP-II asymmetric-energy B Factory located at the Stanford Linear Accelerator Center (SLAC). They find {Beta}(B{sup +} {yields} {rho}{sup +}{gamma}) = (1.20{sub -0.37}{sup +0.42} {+-} 0.20) x 10{sup -6}, {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.97{sub -0.22}{sup +0.24} {+-} 0.06) x 10{sup -6}, and a 90% C.L. upper limit {Beta}(B{sup 0} {yields} {omega}{gamma}) < 0.9 x 10{sup -6}, where the first error is statistical and the second is systematic. They also measure the isospin-violating quantity {Lambda}(B{sup +} {yields} {rho}{sup +}{gamma})/2{Lambda}(B{sup 0} {yields} {rho}{sup 0}{gamma}) - 1 = -0.43{sub -0.22}{sup +0.25} {+-} 0.10.
Date:
August 15, 2008
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Observation of an Excited Charm Baryon Omega^*_C Decaying to Omega^0_C Gamma
The authors report the first observation of an excited singly-charmed baryon {Omega}*{sub c} (css) in the radiative decay {Omega}{sub c}{sup 0}{gamma}, where the {Omega}{sub c}{sup 0} baryon is reconstructed in the decays to the final states {Omega}{sup -}{pi}{sup +}, {Omega}{sup -} {pi}{sup +}{pi}{sup 0}, {Omega}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}, and {Xi}{sup -} K{sup -} {pi}{sup +}{pi}{sup +}. This analysis is performed using a dataset of 230.7 fb{sup -1} collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The mass difference between the {Omega}*{sub c} and the {Omega}{sub c}{sup 0} baryons is measured to be 70.8 {+-} 1.0(stat) {+-} 1.1(syst) MeV/c{sup 2}. They also measure the ratio of inclusive production cross sections of {Omega}*{sub c} and {Omega}{sub c}{sup 0} in e{sup +}e{sup -} annihilation.
Date:
November 15, 2006
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Search For B --> K* Nu Anti-Nu Decays
We present a search for the decays B {yields} K* {nu}{bar {nu}} using 454 x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the SLAC PEP-II B-Factory. We first select an event sample where one B is reconstructed in a semileptonic or hadronic mode with one charmed meson. The remaining particles in the event are then examined to search for a B {yields} K* {nu}{bar {nu}} decay. The charged K* is reconstructed as K*{sup +} {yields} K{sub S}{sup 0}{pi}{sup +} or K*{sup +} {yields} K{sup +}{pi}{sup 0}; the neutral K* is identified in K*{sup 0} {yields} K{sup +}{pi}{sup -} mode. We establish upper limits at 90% confidence level of {Beta}(B{sup +} {yields} K*{sup +} {nu}{bar {nu}}) < 8 x 10{sup -5}, {Beta}(B{sup 0} {yields} K*{sup 0} {nu}{bar {nu}}) < 12 x 10{sup -5}, and {Beta}(B {yields} K* {nu}{bar {nu}}) < 8 x 10{sup -5}.
Date:
August 15, 2008
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Search for Lepton Flavor Violating Decays $\tau^\pm \to \ell^\pm{\pi^0}, \ell^\pm\eta, \ell^\pm{\eta^\prime}$
A search for lepton flavor violating decays of the {tau} lepton to a lighter mass lepton and a pseudoscalar meson has been performed using 339 fb{sup -1} of e{sup +}e{sup -} annihilation data collected at a center-of-mass energy near 10.58GeV by the BABAR detector at the SLAC PEP-II storage ring. No evidence of signal has been found, and upper limits on the branching fractions are set at 10{sup -7} level.
Date:
November 15, 2006
Creator:
Aubert, B.
Object Type:
Article
System:
The UNT Digital Library
Study of Inclusive $B^-$ and $\bar{B}^0$ Decays toFlavor-Tagged $D$, $D_s$ and $\Lambda_c$
We report on a study of inclusive B{sup -} and {bar B}{sup 0} meson decays to D{sup 0}X, {bar D}{sup 0}X, D{sup +}X, D{sup -}X, D{sub s}{sup +}X, D{sub s}{sup -}X, {Lambda}{sub c}{sup +}X, {bar {Lambda}}{sub c}{sup -}X, based on a sample of 231 million B{bar B} events recorded with the BABAR detector at the {Upsilon}(4S) resonance. Events are selected by completely reconstructing one B and searching for a reconstructed charm particle in the rest of the event. From the measured branching fractions of these decays, we infer the number of charm and anti-charm particles per {bar B} decay, separately for charged and neutral parents. We derive the total charm yield per B{sup -} decay, n{sub c}{sup -} = 1.202 {+-} 0.023 {+-} 0.040{sub -0.029}{sup +0.035}, and per {bar B}{sup 0} decay, n = 1.193 {+-} 0.030 {+-} 0.034{sub -0.035}{sup +0.044} where the first uncertainty is statistical, the second is systematic, and the third reflects the charm branching-fraction uncertainties. We also present the charm momentum distributions measured in the {bar B} rest frame.
Date:
June 15, 2006
Creator:
Aubert, B.
Object Type:
Report
System:
The UNT Digital Library
Study of the pi+pi-J//psi Mass Spectrum Via Initial State Radiation at BaBar
We present an update of the study of the Y(4260) resonance, produced in the process e{sup +}e{sup -} {yields} {gamma}{sub ISR} {pi}{sup +}{pi}{sup -} J/{psi} using initial-state radiation events at the PEP-II e{sup +}e{sup -} storage rings. This study is based on 454 fb{sup -1} of data recorded with the BABAR detector at a center-of-mass energy in the {Upsilon}(4S) resonance region. From a fit with a single non-relativistic Breit-Wigner shape we obtain updated parameters for the Y(4260) resonance which are m{sub Y} = 4252 {+-} 6{sub -3}{sup +2} MeV/c{sup 2} and {Lambda}{sub Y} = 105 {+-} 18{sub -6}{sup +4} MeV/c{sup 2}; we also measure {Beta}({pi}{sup +}{pi}{sup -} J/{psi}){Lambda}{sub e{sup +}e{sup -}} = (7.5 {+-} 0.9 {+-} 0.8) eV. We cannot confirm the recent BELLE observation of a broad structure around 4.05GeV/c{sup 2} in this decay mode.
Date:
August 15, 2008
Creator:
Aubert, Bernard
Object Type:
Article
System:
The UNT Digital Library
Commercial Demonstration of Wood Recovery, Recycling, and Value Adding Technologies
This commercial demonstration project demonstrated the technical feasibility of converting low-value, underutilized and waste stream solid wood fiber material into higher valued products. With a growing need to increase product/production yield and reduce waste in most sawmills, few recovery operations and practically no data existed to support the viability of recovery operations. Prior to our efforts, most all in the forest products industry believed that recovery was difficult, extremely labor intensive, not cost effective, and that recovered products had low value and were difficult to sell. This project provided an opportunity for many within the industry to see through demonstration that converting waste stream material into higher valued products does in fact offer a solution. Our work, supported by the U.S. Department of Energy, throughout the project aimed to demonstrate a reasonable approach to reducing the millions of recoverable solid wood fiber tons that are annually treated as and converted into low value chips, mulch and fuel. Consequently sawmills continue to suffer from reduced availability of forest resources, higher raw material costs, growing waste disposal problems, increased global competition, and more pressure to operate in an Environmentally Friendly manner. It is our belief (based upon the experience of this project) …
Date:
July 15, 2004
Creator:
Auburn Machinery, Inc.
Object Type:
Report
System:
The UNT Digital Library
Science and technology of ultrananocrystalline diamond (UNCD) thin films for multifunctional devices.
MEMS devices are currently fabricated primarily in silicon because of the available surface machining technology. However, Si has poor mechanical and tribological properties, and practical MEMS devices are currently limited primarily to applications involving only bending and flexural motion, such as cantilever accelerometers and vibration sensors, However, because of the poor flexural strength and fracture toughness of Si, and the tendency of Si to adhere to hydrophyllic surfaces, even these simple devices have limited dynamic range. Future MEMS applications that involve significant rolling or sliding contact will require the use of new materials with significantly improved mechanical and tribological properties, and the ability to perform well in harsh environments. Diamond is a superhard material of high mechanical strength, exceptional chemical inertness, and outstanding thermal stability. The brittle fracture strength is 23 times that of Si, and the projected wear life of diamond MEMS moving mechanical assemblies (MEMS-MMAS) is 10,000 times greater than that of Si MMAs. However, as the hardest known material, diamond is notoriously difficult to fabricate. Conventional CVD thin film deposition methods offer an approach to the fabrication of ultra-small diamond structures, but the films have large grain size, high internal stress, poor intergranular adhesion, and very rough …
Date:
November 15, 2000
Creator:
Auciello, O.; Gruen, D. M.; Krauss, A. R.; Jayatissa, A.; Sumant, A.; Tucek, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Analysis of the growth of strike-slip faults using effective medium theory
Increases in the dimensions of strike-slip faults including fault length, thickness of fault rock and the surrounding damage zone collectively provide quantitative definition of fault growth and are commonly measured in terms of the maximum fault slip. The field observations indicate that a common mechanism for fault growth in the brittle upper crust is fault lengthening by linkage and coalescence of neighboring fault segments or strands, and fault rock-zone widening into highly fractured inner damage zone via cataclastic deformation. The most important underlying mechanical reason in both cases is prior weakening of the rocks surrounding a fault's core and between neighboring fault segments by faulting-related fractures. In this paper, using field observations together with effective medium models, we analyze the reduction in the effective elastic properties of rock in terms of density of the fault-related brittle fractures and fracture intersection angles controlled primarily by the splay angles. Fracture densities or equivalent fracture spacing values corresponding to the vanishing Young's, shear, and quasi-pure shear moduli were obtained by extrapolation from the calculated range of these parameters. The fracture densities or the equivalent spacing values obtained using this method compare well with the field data measured along scan lines across the faults …
Date:
October 15, 2009
Creator:
Aydin, A. & Berryman, J.G.
Object Type:
Article
System:
The UNT Digital Library
First Operation of a Free-Electron Laser Generating GW Power Radiation at 32-Nm Wavelength
Many scientific disciplines ranging from physics, chemistry and biology to material sciences, geophysics and medical diagnostics need a powerful X-ray source with pulse lengths in the femtosecond range. This would allow, for example, time-resolved observation of chemical reactions with atomic resolution. Such radiation of extreme intensity, and tunable over a wide range of wavelengths, can be accomplished using high-gain free-electron lasers (FEL). Here we present results of the first successful operation of an FEL at a wavelength of 32 nm, with ultra-short pulses (25 fs FWHM), a peak power at the Gigawatt level, and a high degree of transverse and longitudinal coherence. The experimental data are in full agreement with theory. This is the shortest wavelength achieved with an FEL to date and an important milestone towards a user facility designed for wavelengths down to 6 nm. With a peak brilliance exceeding the state-of-the-art of synchrotron radiation sources by seven orders of magnitude, this device opens a new field of experiments, and it paves the way towards sources with even shorter wavelengths, such as the Linac Coherent Light Source at Stanford, USA, and the European X-ray Free Electron Laser Facility in Hamburg, Germany.
Date:
September 15, 2006
Creator:
Ayvazian, V.; Baboi, N.; Bahr, J.; Balandin, V.; Beutner, B.; Brandt, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Meso-scale machining capabilities and issues
Meso-scale manufacturing processes are bridging the gap between silicon-based MEMS processes and conventional miniature machining. These processes can fabricate two and three-dimensional parts having micron size features in traditional materials such as stainless steels, rare earth magnets, ceramics, and glass. Meso-scale processes that are currently available include, focused ion beam sputtering, micro-milling, micro-turning, excimer laser ablation, femto-second laser ablation, and micro electro discharge machining. These meso-scale processes employ subtractive machining technologies (i.e., material removal), unlike LIGA, which is an additive meso-scale process. Meso-scale processes have different material capabilities and machining performance specifications. Machining performance specifications of interest include minimum feature size, feature tolerance, feature location accuracy, surface finish, and material removal rate. Sandia National Laboratories is developing meso-scale electro-mechanical components, which require meso-scale parts that move relative to one another. The meso-scale parts fabricated by subtractive meso-scale manufacturing processes have unique tribology issues because of the variety of materials and the surface conditions produced by the different meso-scale manufacturing processes.
Date:
May 15, 2000
Creator:
BENAVIDES,GILBERT L.; ADAMS,DAVID P. & YANG,PIN
Object Type:
Article
System:
The UNT Digital Library
CONTROL OF DYNAMIC APERTURE FOR SYNCHROTRON LIGHT SOURCES.
A summary of how modern analytical and numerical techniques enable one to construct a realistic model of state-of-the-art synchrotron light sources is provided. The effects of engineering tolerances and radiation are included in a self-consistent manner. An approach for utilizing these tools to develop an effective strategy for the design and control of the dynamic aperture for such dynamical systems is also outlined.
Date:
May 15, 2005
Creator:
BENGTSSON, J.
Object Type:
Article
System:
The UNT Digital Library
Accurate Time-Linked Data Acqusition System Field Deploymemt and Operational Experience
None
Date:
November 15, 2000
Creator:
BERG,DALE E. & ZAYAS,JOSE R.
Object Type:
Article
System:
The UNT Digital Library
EFFECTS OF HUMIDITY AND OTHER VARIABLES ON THE STRENGTH OF PBX 9501
None
Date:
September 15, 2000
Creator:
BROWNING, R. Y. & MEYER, T.
Object Type:
Article
System:
The UNT Digital Library
H02 WETLAND TREATMENT SYSTEM WATER CHEMISTRY SAMPLING AND RESULTS REPORT
The H-02 Wetland Treatment System (Figure 1) is used to remove heavy metals (e.g., copper and zinc) from the H-Area process and storm water discharge. Routine flow enters an equalization basin by inlets on either the east (Location 1) or west end (Location 2). The west end influent constitutes 75% of the average flow into the basin which has an average residence time of approximately 3 days at low pool (i.e., 120 gal/min. through a volume of 0.5 million gallons). The water then exits via the basin outlet on the east end. Next, the water flows to a splitter box (Location 3) which evenly separates the flow between two wetland cells for a design flow of 60 gal/min. per wetland cell with a residence time in the cell of approximately 2 days. The wetland effluent is then combined (Location 4) and flows through a spillway before reaching the National Pollution Discharge Elimination System (NPDES) measurement point near Road 4. During initial operation, it was observed that the pH of the water leaving the equalization basin was elevated compared to the influent pH. Furthermore, the elevated pH remained through the wetland cells so that there was an average pH of 10 …
Date:
February 15, 2008
Creator:
Bach, M; Michael Serrato, M & Eric Nelson, E
Object Type:
Report
System:
The UNT Digital Library
Defense Contracting in Iraq: Issues and Options for Congress
This report examines logistical support contracts for troop support services in Iraq primarily administered through the U.S. Army's Logistics Civil Augmentation Program (LOGCAP).
Date:
August 15, 2008
Creator:
Bailey Grasso, Valerie
Object Type:
Report
System:
The UNT Digital Library
The NAS Parallel Benchmarks
The NAS Parallel Benchmarks (NPB) are a suite of parallel computer performance benchmarks. They were originally developed at the NASA Ames Research Center in 1991 to assess high-end parallel supercomputers. Although they are no longer used as widely as they once were for comparing high-end system performance, they continue to be studied and analyzed a great deal in the high-performance computing community. The acronym 'NAS' originally stood for the Numerical Aeronautical Simulation Program at NASA Ames. The name of this organization was subsequently changed to the Numerical Aerospace Simulation Program, and more recently to the NASA Advanced Supercomputing Center, although the acronym remains 'NAS.' The developers of the original NPB suite were David H. Bailey, Eric Barszcz, John Barton, David Browning, Russell Carter, LeoDagum, Rod Fatoohi, Samuel Fineberg, Paul Frederickson, Thomas Lasinski, Rob Schreiber, Horst Simon, V. Venkatakrishnan and Sisira Weeratunga. The original NAS Parallel Benchmarks consisted of eight individual benchmark problems, each of which focused on some aspect of scientific computing. The principal focus was in computational aerophysics, although most of these benchmarks have much broader relevance, since in a much larger sense they are typical of many real-world scientific computing applications. The NPB suite grew out of the …
Date:
November 15, 2009
Creator:
Bailey, David H.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of the Final Report: Waste Package Materials Performance Peer Review Panel
None
Date:
August 15, 2002
Creator:
Bailey, J. N.; Cloud, J. D.; Rodgers, T. E. & Summers, S. E.
Object Type:
Report
System:
The UNT Digital Library
A Piecewise Linear Finite Element Discretization of the Diffusion Equation for Arbitrary Polyhedral Grids
We develop a piecewise linear (PWL) Galerkin finite element spatial discretization for the multi-dimensional radiation diffusion equation. It uses piecewise linear weight and basis functions in the finite element approximation, and it can be applied on arbitrary polygonal (2D) or polyhedral (3D) grids. We show that this new PWL method gives solutions comparable to those from Palmer's finite-volume method. However, since the PWL method produces a symmetric positive definite coefficient matrix, it should be substantially more computationally efficient than Palmer's method, which produces an asymmetric matrix. We conclude that the Galerkin PWL method is an attractive option for solving diffusion equations on unstructured grids.
Date:
July 15, 2005
Creator:
Bailey, T S; Adams, M L; Yang, B & Zika, M R
Object Type:
Article
System:
The UNT Digital Library
Bottom production
In the context of the LHC experiments, the physics of bottom flavoured hadrons enters in different contexts. It can be used for QCD tests, it affects the possibilities of B decays studies, and it is an important source of background for several processes of interest. The physics of b production at hadron colliders has a rather long story, dating back to its first observation in the UA1 experiment. Subsequently, b production has been studied at the Tevatron. Besides the transverse momentum spectrum of a single b, it has also become possible, in recent time, to study correlations in the production characteristics of the b and the b. At the LHC new opportunities will be offered by the high statistics and the high energy reach. One expects to be able to study the transverse momentum spectrum at higher transverse momenta, and also to exploit the large statistics to perform more accurate studies of correlations.
Date:
March 15, 2000
Creator:
Baines, J.; Baranov, S. P.; Bartalini, P.; Bay, A.; Bouhova, E.; Cacciari, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Oxidation Resistance and Microstructure of Ru-Capped Extreme Ultraviolet Lithography Multilayers
The oxidation resistance of protective capping layers for extreme ultraviolet lithography (EUVL) multilayers depends on their microstructure. Differently prepared Ru-capping layers, deposited on Mo/Si EUVL multilayers, were investigated to establish their baseline structural, optical, and surface properties in as-deposited state. The same capping layer structures were then tested for their thermal stability and oxidation resistance. The best performing Ru-capping layer structure was analyzed in detail with transmission electron microscopy (TEM). As compared to other Ru capping layers preparations studied here it is the only one that shows grains with preferential orientation. This information is essential for modeling and performance optimization of EUVL multilayers.
Date:
June 15, 2005
Creator:
Bajt, S.; Dai, Z.; Nelson, E. J.; Wall, M. A.; Alameda, J. B.; Nguyen, N. et al.
Object Type:
Article
System:
The UNT Digital Library
Practical superconductor development for electric power applications.
None
Date:
November 15, 2000
Creator:
Balachandran, U.
Object Type:
Report
System:
The UNT Digital Library
Hydrogen Production and Delivery Research
In response to DOE's Solicitation for Grant Applications DE-PS36-03GO93007, 'Hydrogen Production and Delivery Research', SRI International (SRI) proposed to conduct work under Technical Topic Area 5, Advanced Electrolysis Systems; Sub-Topic 5B, High-Temperature Steam Electrolysis. We proposed to develop a prototype of a modular industrial system for low-cost generation of H{sub 2} (<$2/kg) by steam electrolysis with anodic depolarization by CO. Water will be decomposed electrochemically into H{sub 2} and O{sub 2} on the cathode side of a high-temperature electrolyzer. Oxygen ions will migrate through an oxygen-ion-conductive solid oxide electrolyte. Gas mixtures on the cathode side (H{sub 2} + H{sub 2}O) and on the anode side (CO + CO{sub 2}) will be reliably separated by the solid electrolyte. Depolarization of the anodic process will decrease the electrolysis voltage, and thus the electricity required for H{sub 2} generation and the cost of produced H{sub 2}. The process is expected to be at least 10 times more energy-efficient than low-temperature electrolysis and will generate H{sub 2} at a cost of approximately $1-$1.5/kg. The operating economics of the system can be made even more attractive by deploying it at locations where waste heat is available; using waste heat would reduce the electricity required for …
Date:
October 15, 2007
Creator:
Balachov, Iouri
Object Type:
Report
System:
The UNT Digital Library
Risk Reduction With a Fuzzy Expert Exploration Tool
Incomplete or sparse information on types of data such as geologic or formation characteristics introduces a high level of risk for oil exploration and development projects. ''Expert'' systems developed and used in several disciplines and industries have demonstrated beneficial results. A state-of-the-art exploration ''expert'' tool, relying on a computerized database and computer maps generated by neural networks, is being developed through the use of ''fuzzy'' logic, a relatively new mathematical treatment of imprecise or non-explicit parameters and values. Oil prospecting risk can be reduced with the use of a properly developed and validated ''Fuzzy Expert Exploration (FEE) Tool.'' This FEE Tool can be beneficial in many regions of the U.S. by enabling risk reduction in oil and gas prospecting as well as decreased prospecting and development costs. In the 1998-1999 oil industry environment, many smaller exploration companies lacked the resources of a pool of expert exploration personnel. Downsizing, low oil prices, and scarcity of exploration funds have also affected larger companies, and will, with time, affect the end users of oil industry products in the U.S. as reserves are depleted. The pool of experts is much reduced today. The FEE Tool will benefit a diverse group in the U.S., leading …
Date:
April 15, 2003
Creator:
Balch, Robert
Object Type:
Report
System:
The UNT Digital Library