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Frequency Doubling Broadband Light in Multiple Crystals (open access)

Frequency Doubling Broadband Light in Multiple Crystals

The authors compare frequency doubling of broadband light in a single nonlinear crystal with doubling in five crystals with intercrystal temporal walk off compensation, and with doubling in five crystals adjusted for offset phase matching frequencies. Using a plane-wave, dispersive numerical model of frequency doubling they study the bandwidth of the second harmonic and the conversion efficiency as functions of crystal length and fundamental irradiance. For low irradiance the offset phase matching arrangement has lower efficiency than a single crystal of the same total length but gives a broader second harmonic bandwidth. The walk off compensated arrangement gives both higher conversion efficiency and broader bandwidth than a single crystal. At high irradiance, both multicrystal arrangements improve on the single crystal efficiency while maintaining broad bandwidth.
Date: July 26, 2000
Creator: ALFORD,WILLIAM J. & SMITH,ARLEE V.
Object Type: Article
System: The UNT Digital Library
Simulation of the Future LSST Data Pipelines (open access)

Simulation of the Future LSST Data Pipelines

In this paper we describe our approach to build a pipeline simulator for the future Large-scale Synoptic Survey Telescope (LSST). The simulated pipeline will be used to research and evaluate software architectures that are efficient and flexible. It will also be used to define the real-time software and hardware requirements needed to support the anticipated LSST data rates. The LSST data pipeline requirements are still being defined, however, previous surveys can provide a good source for data requirements. Our approach is to use the SuperMacho data pipeline as a prototyping tool to identify a framework for building Modular Data-Centric Pipeline (MDCP) architectures. The prototyping is done in a hierarchical fashion to help capture and define the general data attributes (schema) first. We then model other necessary components based on science and performance requirements. We use identified schemas or data attributes as a way to define a data model for LSST.
Date: July 26, 2004
Creator: Abdulla, Ghaleb M.
Object Type: Article
System: The UNT Digital Library
A New Dynamical Diffraction-Based Technique of the Residual Stress Measurements in Thin Films (open access)

A New Dynamical Diffraction-Based Technique of the Residual Stress Measurements in Thin Films

The recently discovered dynamical diffraction effect ''neutron camel'' was used for the residual stress measurements in a thick Si(111) crystal coated with a 2000 {angstrom} thick Ni film. The observed asymmetry of the back-face rocking curve corresponds to the bending radius of {approx} 19 km and the tension force applied to the Ni film is {approx} 90 N/m. Relative deformation of the Si crystallographic cells in the vicinity of diffractive surfaces is |{partial_derivative}u{sub z}/{partial_derivative}z| {approx} 1.6 x 10{sup -6}.
Date: July 26, 2001
Creator: Agamalian, M.
Object Type: Article
System: The UNT Digital Library
European Trade Retaliation: The FSC-ETI Case (open access)

European Trade Retaliation: The FSC-ETI Case

None
Date: July 26, 2006
Creator: Aheam, Raymond J.
Object Type: Report
System: The UNT Digital Library
Trade Conflict and the U.S.-European Union Economic Relationship (open access)

Trade Conflict and the U.S.-European Union Economic Relationship

The United States and the European Union (EU) share a huge, dynamic, and mutually beneficial economic partnership. Not only is the U.S.-EU trade and investment relationship the largest in the world, but it is also arguably the most important. Agreement between the two partners in the past has been critical to making the world trading system more open and efficient.
Date: July 26, 2006
Creator: Ahearn, Raymond J.
Object Type: Report
System: The UNT Digital Library
Status of the Nif Power Conditioning System (open access)

Status of the Nif Power Conditioning System

The NIF Power Conditioning System provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) storage up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 {micro}s pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of the NIF Power Conditioning continue to progress rapidly, with the goals of completing accelerated production in late 2007 and finishing commissioning by early 2008, all the while maintaining an aggressive operations schedule. To date, more than 80% of the required modules have been assembled, shipped and installed in the facility, representing more that 240 MJ of stored energy available for driving NIF flashlamps. The MESMs have displayed outstanding reliability during daily, multiple-shift operations.
Date: July 26, 2007
Creator: Arnold, P.; Hulsey, S.; Ullery, G.; Petersen, D.; Pendleton, D.; Ollis, C. et al.
Object Type: Article
System: The UNT Digital Library
Environmental Monitoring at the Savannah River Plant, Annual Report - 1973 (open access)

Environmental Monitoring at the Savannah River Plant, Annual Report - 1973

This report summarizes results obtained from the environmental monitoring program at the Savannah River Plant during 1973. A brief discussion of plant releases to the environment and radioactivity detected in the environment is presented in the text and tables. The appendix contains tables of results from environmental sample analyses, sensitivities of laboratory analyses, and maps of sampling locations.
Date: July 26, 2001
Creator: Ashley, C.
Object Type: Report
System: The UNT Digital Library
Environmental Monitoring at the Savannah River Plant, Annual Report - 1981 (open access)

Environmental Monitoring at the Savannah River Plant, Annual Report - 1981

An environmental monitoring program has been in existence at SRP since 1951. The original preoperational surveys have evolved into an extensive environmental monitoring program in which sample types from approximately 500 locations are analyzed for radiological and/or nonradiological parameters. The results of these analyses for 1981 are presented in this report.
Date: July 26, 2001
Creator: Ashley, C.
Object Type: Report
System: The UNT Digital Library
Hough Transform Based Corner Detection for Laser Beam Positioning (open access)

Hough Transform Based Corner Detection for Laser Beam Positioning

In laser beam alignment in addition to detecting position, one must also determine the rotation of the beam. This is essential when a commissioning new laser beam for National Ignition Facility located at the Lawrence Livermore National Laboratory. When the beam is square, the positions of the corners with respect to one another provides an estimate of the rotation of the beam. This work demonstrates corner detection in the presence or absence of a second order non-uniform illumination caused by a spatial mask. The Hough transform coupled with illumination dependent pre-processing is used to determine the corner points. We show examples from simulated and real NIF images.
Date: July 26, 2005
Creator: Awwal, A. S.
Object Type: Article
System: The UNT Digital Library
Automobile and Light Truck Fuel Economy: Is CAFE Up to Standards? (open access)

Automobile and Light Truck Fuel Economy: Is CAFE Up to Standards?

One of the least controversial provisions of the Energy Policy and Conservation Act of 1975 (P.L. 94-163) established corporate average fuel economy (CAFE) standards for new passenger cars. This report presents a brief background and analysis regarding the price of crude oil that brought into sharp focus the fuel inefficiency of U.S. automobiles. The report also discusses the previous issues and the most recent developments regarding CAFE.
Date: July 26, 2002
Creator: Bamberger, Robert L.
Object Type: Report
System: The UNT Digital Library
Report to DHS on Summer Internship 2006 (open access)

Report to DHS on Summer Internship 2006

This summer I worked at Lawrence Livermore National Laboratory in a bioforensics collection and extraction research group under David Camp. The group is involved with researching efficiencies of various methods for collecting bioforensic evidence from crime scenes. The different methods under examination are a wipe, swab, HVAC filter and a vacuum. The vacuum is something that has particularly gone uncharacterized. My time was spent mostly on modeling and calculations work, but at the end of the summer I completed my internship with a few experiments to supplement my calculations. I had two major projects this summer. My first major project this summer involved fluid mechanics modeling of collection and extraction situations. This work examines different fluid dynamic models for the case of a micron spore attached to a fiber. The second project I was involved with was a statistical analysis of the different sampling techniques.
Date: July 26, 2006
Creator: Beckwith, R H
Object Type: Report
System: The UNT Digital Library
Autonomous observing strategies for the ocean carbon cycle (open access)

Autonomous observing strategies for the ocean carbon cycle

Understanding the exchanges of carbon between the atmosphere and ocean and the fate of carbon delivered to the deep sea is fundamental to the evaluation of ocean carbon sequestration options. An additional key requirement is that sequestration must be verifiable and that environmental effects be monitored and minimized. These needs can be addressed by carbon system observations made from low-cost autonomous ocean-profiling floats and gliders. We have developed a prototype ocean carbon system profiler based on the Sounding Oceanographic Lagrangian Observer (SOLO; Davis et al., 1999). The SOLO/ carbon profiler will measure the two biomass components of the carbon system and their relationship to physical variables, such as upper ocean stratification and mixing. The autonomous observations within the upper 1500 m will be made on daily time scales for periods of months to seasons and will be carried out in biologically dynamic locations in the world's oceans that are difficult to access with ships (due to weather) or observe using remote sensing satellites (due to cloud cover). Such an observational capability not only will serve an important role in carbon sequestration research but will provide key observations of the global ocean's natural carbon cycle.
Date: July 26, 2000
Creator: Bishop, James K. & Davis, Russ E.
Object Type: Article
System: The UNT Digital Library
CP VIOLATION IN K DECAY FROM LATTICE QCD, RIKEN BNL RESEARCH CENTER, RBRC AND PARTICLE PHYSICS SEMINAR, BROOKHAVEN NATIONAL LABORATORY, UPTON, N.Y., JULY 26, 2001. (open access)

CP VIOLATION IN K DECAY FROM LATTICE QCD, RIKEN BNL RESEARCH CENTER, RBRC AND PARTICLE PHYSICS SEMINAR, BROOKHAVEN NATIONAL LABORATORY, UPTON, N.Y., JULY 26, 2001.

The entire history of the discoveries of K{sub L}{sup o} and violations of T and CP began at Brookhaven. It is most appropriate for us to hold today's special seminar on CP Violation in K decay in this laboratory. Forty-five years ago, in the same paper on parity nonconservation, it was also pointed out that there is no proof of T symmetry in the weak interaction, nor of C invariance. That paper was submitted to the Physical Review (then, also located at BNL) on June 22, 1956. A month later, Lederman and his collaborators discovered a long-lived neutral V particle (now called K{sub L}{sup o}) at the Cosmotron using the cloud chamber. This discovery was presented as a rigorous proof of C symmetry. In the same summer at Brookhaven, in collaboration with Oehme and Yang, I did the analysis on the neutral kaon system, assuming T, C and CP violations (but based on CPT symmetry). In that work, the two non-orthogonal eigen-states {psi}{sub +} and {psi}{sub -} (now K{sub S}{sup o} and K{sub L}{sup o}) were characterized by a non-orthogonality parameter {alpha} ({approx_equal} 2 Re{epsilon} in today's notation), which was shown to be small, because of unitarity. We then went …
Date: July 26, 2001
Creator: Blum, T. & Mawhinney, R.
Object Type: Report
System: The UNT Digital Library
Microanalytical Methods for Bio-Forensics Investigations (open access)

Microanalytical Methods for Bio-Forensics Investigations

None
Date: July 26, 2006
Creator: Brewer, L N; Weber, P K; Grant, R P; Ghosal, S & Michael, J R
Object Type: Article
System: The UNT Digital Library
The Department of the Treasury’s Authority to Regulate GSE Debt: A Legal Analysis (open access)

The Department of the Treasury’s Authority to Regulate GSE Debt: A Legal Analysis

None
Date: July 26, 2004
Creator: Brooks, Nathan
Object Type: Report
System: The UNT Digital Library
FILTR: Flash Isotope Library and Training Resource (open access)

FILTR: Flash Isotope Library and Training Resource

The subject of radiation detection is replete with complex concepts and challenging nomenclature. Furthermore, a daunting variety of radioactive isotopes may be encountered during the routine operation of a radiation detector. Individuals tasked with searching for illicit sources of radiation must remain vigilant while navigating through more frequently encountered mundane and legitimate radioactive sources. The Flash Isotope Library and Training Resource (FILTR) is being developed as an easily accessible and intuitive reference tool to manage the high volume of complex information required for this task. FILTR is an extended version of the Primary Utility for Nuclear Terminology (PUNT) software developed by the Counter Measures Test Beds group at Lawrence Livermore National Laboratory for the United States Secret Service. Authored in the Flash multimedia development environment, FILTR contains detailed information on potentially encountered isotopes as well as training on radiation and operational procedures. Reference material is organized to present critical information quickly while facilitating more in-depth investigation through an intuitive interface and engaging content. FILTR is being developed for a diverse audience of law enforcement organizations and government agencies and a wide range of skill sets from expert analysts to officers whose primary role is not radiation detection. Additionally, the wide …
Date: July 26, 2007
Creator: Campbell, D & Trombino, D
Object Type: Report
System: The UNT Digital Library
State and Local Preparedness for Terrorism: Policy Issues and Options (open access)

State and Local Preparedness for Terrorism: Policy Issues and Options

None
Date: July 26, 2002
Creator: Canada, Ben
Object Type: Report
System: The UNT Digital Library
Student Loans in Bankruptcy (open access)

Student Loans in Bankruptcy

This report examines the history of student loan nondischargeability in bankruptcy law and the bills introduced to amend treatment of loans in bankruptcy.
Date: July 26, 2007
Creator: Chen, Duke
Object Type: Report
System: The UNT Digital Library
Final Report on California Regional Wind Energy Forecasting Project:Application of NARAC Wind Prediction System (open access)

Final Report on California Regional Wind Energy Forecasting Project:Application of NARAC Wind Prediction System

Wind power is the fastest growing renewable energy technology and electric power source (AWEA, 2004a). This renewable energy has demonstrated its readiness to become a more significant contributor to the electricity supply in the western U.S. and help ease the power shortage (AWEA, 2000). The practical exercise of this alternative energy supply also showed its function in stabilizing electricity prices and reducing the emissions of pollution and greenhouse gases from other natural gas-fired power plants. According to the U.S. Department of Energy (DOE), the world's winds could theoretically supply the equivalent of 5800 quadrillion BTUs of energy each year, which is 15 times current world energy demand (AWEA, 2004b). Archer and Jacobson (2005) also reported an estimation of the global wind energy potential with the magnitude near half of DOE's quote. Wind energy has been widely used in Europe; it currently supplies 20% and 6% of Denmark's and Germany's electric power, respectively, while less than 1% of U.S. electricity is generated from wind (AWEA, 2004a). The production of wind energy in California ({approx}1.2% of total power) is slightly higher than the national average (CEC & EPRI, 2003). With the recently enacted Renewable Portfolio Standards calling for 20% of renewables in …
Date: July 26, 2005
Creator: Chin, H S
Object Type: Report
System: The UNT Digital Library
Electron-Cloud Simulation and Theory for High-Current Heavy-Ion Beams (open access)

Electron-Cloud Simulation and Theory for High-Current Heavy-Ion Beams

Stray electrons can arise in positive-ion accelerators for heavy ion fusion or other applications as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary- electron emission. We summarize the distinguishing features of electron cloud issues in heavy-ion-fusion accelerators and a plan for developing a self-consistent simulation capability for heavy-ion beams and electron clouds. We also present results from several ingredients in this capability: (1) We calculate the electron cloud produced by electron desorption from computed beam-ion loss, which illustrates the importance of retaining ion reflection at the walls. (2) We simulate of the effect of specified electron cloud distributions on ion beam dynamics. We consider here electron distributions with axially varying density, centroid location, or radial shape, and examine both random and sinusoidally varying perturbations. We find that amplitude variations are most effective in spoiling ion beam quality, though for sinusoidal variations which match the natural ion beam centroid oscillation or breathing mode frequencies, the centroid and shape perturbations can also have significant impact. We identify an instability associated with a resonance between the beam-envelope ''breathing'' mode and the electron perturbation. We estimate its growth rate, which …
Date: July 26, 2004
Creator: Cohen, R; Friedman, A; Lund, S; Molvik, A; Lee, E; Azevedo, T et al.
Object Type: Article
System: The UNT Digital Library
Water Quality Issues in the 110th Congress: Oversight and Implementation (open access)

Water Quality Issues in the 110th Congress: Oversight and Implementation

None
Date: July 26, 2007
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Africa: U.S. Foreign Assistance Issues (open access)

Africa: U.S. Foreign Assistance Issues

This report discusses the issue of U.S. economic assistance to sub-Saharan Africa, highlighting the importance of continued assistance in light of U.S. national security and also various U.S.-led efforts to promote reform amongst African citizens themselves. U.S. assistance finds its way to Africa through a variety of channels, including the USAID-administered DA program, food aid programs, and indirect aid provided through international financial institutions and the United Nations.
Date: July 26, 2005
Creator: Copson, Raymond W.
Object Type: Report
System: The UNT Digital Library
HIV/AIDS International Programs: Appropriations, FY2003-FY2006 (open access)

HIV/AIDS International Programs: Appropriations, FY2003-FY2006

House-passed appropriations for Foreign Operations, Labor/Health and Human Services, and Agriculture would provide a total of just over $3.2 billion for international HIV/AIDS, tuberculosis, and malaria programs, compared with an Administration request of just under $3.2 billion.
Date: July 26, 2005
Creator: Copson, Raymond W.
Object Type: Report
System: The UNT Digital Library
Death Valley Lower Carbonate Aquifer Monitoring Program Wells Down gradient of the Proposed Yucca Mountain Nuclear Waste Repository (open access)

Death Valley Lower Carbonate Aquifer Monitoring Program Wells Down gradient of the Proposed Yucca Mountain Nuclear Waste Repository

Inyo County has participated in oversight activities associated with the Yucca Mountain Nuclear Waste Repository since 1987. The overall goal of these studies are the evaluation of far-field issues related to potential transport, by ground water, or radionuclides into Inyo County, including Death Valley, and the evaluation of a connection between the Lower Carbonate Aquifer (LCA) and the biosphere. Our oversight and completed Cooperative Agreement research, and a number of other investigators research indicate that there is groundwater flow between the alluvial and carbonate aquifers both at Yucca Mountain and in Inyo County. In addition to the potential of radionuclide transport through the LCA, Czarnecki (1997), with the US Geological Survey, research indicate potential radionuclide transport through the shallower Tertiary-age aquifer materials with ultimate discharge into the Franklin Lake Playa in Inyo County. The specific purpose of this Cooperative Agreement drilling program was to acquire geological, subsurface geology, and hydrologic data to: (1) establish the existence of inter-basin flow between the Amargosa Basin and Death Valley Basin; (2) characterize groundwater flow paths in the LCA through Southern Funeral Mountain Range, and (3) Evaluation the hydraulic connection between the Yucca Mountain repository and the major springs in Death Valley through the …
Date: July 26, 2006
Creator: County, Inyo
Object Type: Report
System: The UNT Digital Library