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Border Security: Improvements in the Department of State's Development Process Could Increase the Security of Passport Cards and Border Crossing Cards (open access)

Border Security: Improvements in the Department of State's Development Process Could Increase the Security of Passport Cards and Border Crossing Cards

A letter report issued by the Government Accountability Office with an abstract that begins "In July 2008, the Department of State (State) began issuing passport cards as a lower-cost alternative to passports for U.S. citizens to meet Western Hemisphere Travel Initiative requirements. In October 2008, State began issuing the second generation border crossing card (BCC) based on the architecture of the passport card. GAO was asked to examine the effectiveness of the physical and electronic security features of the passport card and second generation BCC. This report addresses: (1) How effectively State's development process--including testing and evaluation--for the passport card and second generation BCC mitigates the risk of fraudulent use? (2) How are U.S. Customs and Border Protection (CBP) officers using the cards' security features to prevent fraudulent use at land ports of entry? To conduct this work, GAO evaluated the security features of passport cards and second generation BCCs against international standards and guidance and results from testing and evaluation and observed the inspection of these cards at five land ports of entry (POE)."
Date: June 1, 2010
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 41, No. 205, Ed. 1 Tuesday, June 1, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 205, Ed. 1 Tuesday, June 1, 2010

Free weekly newspaper that includes business and classified advertising.
Date: June 1, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Houston, Tex.), Vol. 41, No. 206, Ed. 1 Tuesday, June 1, 2010 (open access)

The Greensheet (Houston, Tex.), Vol. 41, No. 206, Ed. 1 Tuesday, June 1, 2010

Free weekly newspaper that includes business and classified advertising.
Date: June 1, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History

[Kay Littler with students in College of Education]

Photograph of Kay Littler, a professor, standing at the head of a classroom full of Teach North Texas Students. Lauren Thomas is at the front and is wearing a blue t-shirt. They are part of UNT's College of Education. Behind them is cabinet space and storage boxes.
Date: June 1, 2010
Creator: unknown
Object Type: Photograph
System: The UNT Digital Library

[Counter-space in classroom]

Photograph of the counter-space in one of the UNT College of Education classrooms. There are two boxes with the label "Step-1" on them with binders, folders, and papers inside. Other empty, clear boxes are stacked further down the way and cabinets are above the counter.
Date: June 1, 2010
Creator: unknown
Object Type: Photograph
System: The UNT Digital Library

[TNT students at tables in classroom]

Photograph of Teach North Texas students at tables with name-cards on them. Some of the cards read "Sarah", "Franklin E.", and "Chelsea". The students are a part of the UNT College of Education.
Date: June 1, 2010
Creator: unknown
Object Type: Photograph
System: The UNT Digital Library

[Kay Littler at head of classroom]

Photograph of Kay Littler, a professor, speaking to students sitting at tables in a classroom. They are part of the Teach North Texas group in UNT's College of Education. There is a dry-erase board behind Littler and cabinet space along the other wall with storage above and below.
Date: June 1, 2010
Creator: unknown
Object Type: Photograph
System: The UNT Digital Library

[Storage space in classroom]

Photograph of clear empty storage boxes, cabinets, a sink , and a flammable containment cabinet in a classroom. It is part of the UNT College of Education and used by the Teach North Texas group.
Date: June 1, 2010
Creator: unknown
Object Type: Photograph
System: The UNT Digital Library

[Student sitting at table in classroom]

Photograph of a student sitting at a table in a classroom. They are part of the Teach North Texas group in UNT's College of Education. Behind them are shelves with books and binders and several empty boxes for storage.
Date: June 1, 2010
Creator: unknown
Object Type: Photograph
System: The UNT Digital Library
The BErkeley Lab Laser Accelerator (BELLA): A 10 GeV Laser Plasma Accelerator (open access)

The BErkeley Lab Laser Accelerator (BELLA): A 10 GeV Laser Plasma Accelerator

An overview is presented of the design of a 10 GeV laser plasma accelerator (LPA) that will be driven by a PW-class laser system and of the BELLA Project, which has as its primary goal to build and install the required Ti:sapphire laser system for the acceleration experiments. The basic design of the 10 GeV stage aims at operation in the quasi-linear regime, where the laser excited wakes are largely sinusoidal and offer the possibility of accelerating both electrons and positrons. Simulations show that a 10 GeV electron beam can be generated in a meter scale plasma channel guided LPA operating at a density of about 1017 cm-3 and powered by laser pulses containing 30-40 J of energy in a 50- 200 fs duration pulse, focused to a spotsize of 50-100 micron. The lay-out of the facility and laser system will be presented as well as the progress on building the facility.
Date: June 1, 2010
Creator: Leemans, W. P.; Duarte, R.; Esarey, E.; Fournier, S.; Geddes, C. G. R.; Lockhart, D. et al.
Object Type: Article
System: The UNT Digital Library
Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators (open access)

Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators

We present an overview of diagnostic techniques for measuring key parameters of electron bunches from Laser Plasma Accelerators (LPAs). The diagnostics presented here were chosen because they highlight the unique advantages (e.g., diverse forms of electromagnetic emission) and difficulties (e.g., shot-to-shot variability) associated with LPAs. Non destructiveness and high resolution (in space and time and energy) are key attributes that enable the formation of a comprehensive suite of simultaneous diagnostics which are necessary for the full characterization of the ultrashort, but highly-variable electron bunches from LPAs.
Date: June 1, 2010
Creator: Matlis, N. H.; Bakeman, M.; Geddes, C. G. R.; Gonsalves, T.; Lin, C.; Nakamura, K. et al.
Object Type: Article
System: The UNT Digital Library
Summary Report of Working Group 1: Laser-Plasma Acceleration (open access)

Summary Report of Working Group 1: Laser-Plasma Acceleration

Advances in and physics of the acceleration of particles using underdense plasma structures driven by lasers were the topics of presentations and discussions in Working Group 1 of the 2010 Advanced Accelerator Concepts Workshop. Such accelerators have demonstrated gradients several orders beyond conventional machines, with quasi-monoenergetic beams at MeV-GeV energies, making them attractive candidates for next generation accelerators. Workshop discussions included advances in control over injection and laser propagation to further improve beam quality and stability, detailed diagnostics and physics models of the acceleration process, radiation generation as a source and diagnostic, and technological tools and upcoming facilities to extend the reach of laser-plasma accelerators.
Date: June 1, 2010
Creator: Geddes, C.G.R.; Clayton, C.; Lu, W. & Thomas, A.G.R.
Object Type: Article
System: The UNT Digital Library
Remote-Handled Low-Level Waste Disposal Project Alternatives Analysis (open access)

Remote-Handled Low-Level Waste Disposal Project Alternatives Analysis

This report identifies, evaluates, and compares alternatives for meeting the U.S. Department of Energy’s mission need for management of remote-handled low-level waste generated by the Idaho National Laboratory and its tenants. Each alternative identified in the Mission Need Statement for the Remote-Handled Low-Level Waste Treatment Project is described and evaluated for capability to fulfill the mission need. Alternatives that could meet the mission need are further evaluated and compared using criteria of cost, risk, complexity, stakeholder values, and regulatory compliance. The alternative for disposal of remote-handled low-level waste that has the highest confidence of meeting the mission need and represents best value to the government is to build a new disposal facility at the Idaho National Laboratory Site.
Date: June 1, 2010
Creator: Duncan, David
Object Type: Report
System: The UNT Digital Library
Mechanics of layered anisotropic poroelastic media with applications to effective stress for fluid permeability (open access)

Mechanics of layered anisotropic poroelastic media with applications to effective stress for fluid permeability

The mechanics of vertically layered porous media has some similarities to and some differences from the more typical layered analysis for purely elastic media. Assuming welded solid contact at the solid-solid interfaces implies the usual continuity conditions, which are continuity of the vertical (layering direction) stress components and the horizontal strain components. These conditions are valid for both elastic and poroelastic media. Differences arise through the conditions for the pore pressure and the increment of fluid content in the context of fluid-saturated porous media. The two distinct conditions most often considered between any pair of contiguous layers are: (1) an undrained fluid condition at the interface, meaning that the increment of fluid content is zero (i.e., {delta}{zeta} = 0), or (2) fluid pressure continuity at the interface, implying that the change in fluid pressure is zero across the interface (i.e., {delta}p{sub f} = 0). Depending on the types of measurements being made on the system and the pertinent boundary conditions for these measurements, either (or neither) of these two conditions might be directly pertinent. But these conditions are sufficient nevertheless to be used as thought experiments to determine the expected values of all the poroelastic coefficients. For quasi-static mechanical changes …
Date: June 1, 2010
Creator: Berryman, J. G.
Object Type: Article
System: The UNT Digital Library
Optical Sideband Generation: a Longitudinal Electron Beam Diagnostic Beyond the Laser Bandwidth Resolution Limit (open access)

Optical Sideband Generation: a Longitudinal Electron Beam Diagnostic Beyond the Laser Bandwidth Resolution Limit

Electro-optic sampling (EOS) is widely used as a technique to measure THz-domain electric field pulses such asthe self-fields of femtosecond electron beams. We present an EOS-based approach for single-shot spectral measurement that excels in simplicity (compatible with fiber integration) and bandwidth coverage (overcomes the laser bandwidth limitation), allowing few-fs electron beams or single-cycle THz pulses to be characterized with conventional picosecond probes. It is shown that the EOS-induced optical sidebands on the narrow-bandwidth optical probe are spectrally-shifted replicas of the THz pulse. An experimental demonstration on a 0-3 THz source is presented.
Date: June 1, 2010
Creator: Laboratory, Lawrence Berkeley National; Tilborg, J. van; Matlis, N. H.; Plateau, G. R. & Leemans, W. P.
Object Type: Article
System: The UNT Digital Library
Nucleon Magnetic Moments and Electric Polarizabilities (open access)

Nucleon Magnetic Moments and Electric Polarizabilities

Electromagnetic properties of the nucleon are explored with lattice QCD using a novel technique. Focusing on background electric fields, we show how the electric polarizability can be extracted from nucleon correlation functions. A crucial step concerns addressing contributions from the magnetic moment, which affects the relativistic propagation of nucleons in electric fields. By properly handing these contributions, we can determine both magnetic moments and electric po larizabilities. Lattice results from anisotropic clover lattices are presented. Our method is not limited to the neutron; we show results for the proton as well.
Date: June 1, 2010
Creator: Detmold, W. & Walker-Loud, A.
Object Type: Article
System: The UNT Digital Library
Leading order hadronic contribution to g-2 from twisted mass QCD (open access)

Leading order hadronic contribution to g-2 from twisted mass QCD

We calculate the leading order hadronic contribution to the muon anomalous magnetic moment using twisted mass lattice QCD. The pion masses range from 330 MeV to 650 MeV. We use two lattice spacings, a=0.079 fm and 0.063 fm, to study lattice artifacts. Finite-size effects are studied for two values of the pion mass, and we calculate the disconnected contributions for four ensembles. Particular attention is paid to the dominant contributions of the vector mesons, both phenomenologically and from our lattice calculation.
Date: June 1, 2010
Creator: Dru B Renner, Xu Feng, Karl Jansen, Marcus Petschlies
Object Type: Article
System: The UNT Digital Library
Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes (open access)

Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes

Laser-plasma collider designs point to staging of multiple accelerator stages at the 10 GeV level, which are to be developed on the upcoming BELLA laser, while Thomson Gamma source designs use GeV stages, both requiring efficiency and low emittance. Design and scaling of stages operating in the quasi-linear regime to address these needs are presented using simulations in the VORPAL framework. In addition to allowing symmetric acceleration of electrons and positrons, which is important for colliders, this regime has the property that the plasma wakefield is proportional to the transverse gradient of the laser intensity profile. We demonstrate use of higher order laser modes to tailor the laser pulse and hence the transverse focusing forces in the plasma. In particular, we show that by using higher order laser modes, we can reduce the focusing fields and hence increase the matched electron beam radius, which is important to increased charge and efficiency, while keeping the low bunch emittance required for applications.
Date: June 1, 2010
Creator: Geddes, C. G. R.; Cormier-Michel, E.; Esarey, E.; Schroeder, C. B.; Mullowney, P.; Paul, K. et al.
Object Type: Article
System: The UNT Digital Library
Optics, mask and resist implications on contact CDU (open access)

Optics, mask and resist implications on contact CDU

Mask and condenser roughness plays important in contact CDU. Resist blur drives both dose requirements and mask specs. Correlation methods can be used to measure mask contributions to CDU.
Date: June 1, 2010
Creator: Naulleau, Patrick
Object Type: Article
System: The UNT Digital Library
How Many Performance Shaping Factors are Necessary for Human Reliability Analysis? (open access)

How Many Performance Shaping Factors are Necessary for Human Reliability Analysis?

It has been argued that human reliability analysis (HRA) has expended considerable energy on creating detailed representations of human performance through an increasingly long list of performance shaping factors (PSFs). It is not clear, however, to what extent this refinement and expansion of PSFs has enhanced the quality of HRA. Indeed, there is considerable range in the number of PSFs provided by individual HRA methods, ranging from single factor models such as time-reliability curves, up to 50 or more PSFs in some current HRA models. The US Nuclear Regulatory Commission advocates 15 PSFs in its HRA Good Practices (NUREG-1792), while its SPAR-H method (NUREG/CR-6883) espouses the use of eight PSFs and its ATHEANA method (NUREG-1624) features an open-ended number of PSFs. The apparent differences in the optimal number of PSFs can be explained in terms of the diverse functions of PSFs in HRA. The purpose of this paper is to explore the role of PSFs across different stages of HRA, including identification of potential human errors, modeling of these errors into an overall probabilistic risk assessment, quantifying errors, and preventing errors.
Date: June 1, 2010
Creator: Boring, Ronald L.
Object Type: Article
System: The UNT Digital Library
Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams (open access)

Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams

Plasma accelerators may be driven by the ponderomotive force of an intense laser or the space-charge force of a charged particle beam. The implications for accelerator design and the different physical mechanisms of laser-driven and beam-driven plasma acceleration are discussed. Driver propagation is examined, as well as the effects of the excited plasma wave phase velocity. The driver coupling to subsequent plasma accelerator stages for high-energy physics applications is addressed.
Date: June 1, 2010
Creator: Schroeder, C. B.; Esarey, E.; Benedetti, C.; Toth, Cs.; Geddes, C. G. R. & Leemans, W.P.
Object Type: Article
System: The UNT Digital Library
Conceptual Model of Offshore Wind Environmental Risk Evaluation System (open access)

Conceptual Model of Offshore Wind Environmental Risk Evaluation System

In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of offshore wind energy generation projects. The development of ERES for offshore wind is closely allied to a concurrent process undertaken to examine environmental effects of marine and hydrokinetic (MHK) energy generation, although specific risk-relevant attributes will differ between the MHK and offshore wind domains. During FY10, a conceptual design of ERES for offshore wind will be developed. The offshore wind ERES mockup described in this report will provide a preview of the functionality of a fully developed risk evaluation system that will use risk assessment techniques to determine priority stressors on aquatic organisms and environments from specific technology aspects, identify key uncertainties underlying high-risk issues, compile a wide-range of data types in an innovative and flexible data organizing scheme, and inform planning and decision processes with a transparent and technically robust decision-support tool. A fully functional version of ERES for offshore wind will be developed in a subsequent phase of the project.
Date: June 1, 2010
Creator: Anderson, Richard M.; Copping, Andrea E.; Van Cleve, Frances B.; Unwin, Stephen D. & Hamilton, Erin L.
Object Type: Report
System: The UNT Digital Library
Evaluation of the Potential Environmental Impacts from Large-Scale Use and Production of Hydrogen in Energy and Transportation Applications (open access)

Evaluation of the Potential Environmental Impacts from Large-Scale Use and Production of Hydrogen in Energy and Transportation Applications

The purpose of this project is to systematically identify and examine possible near and long-term ecological and environmental effects from the production of hydrogen from various energy sources based on the DOE hydrogen production strategy and the use of that hydrogen in transportation applications. This project uses state-of-the-art numerical modeling tools of the environment and energy system emissions in combination with relevant new and prior measurements and other analyses to assess the understanding of the potential ecological and environmental impacts from hydrogen market penetration. H2 technology options and market penetration scenarios will be evaluated using energy-technology-economics models as well as atmospheric trace gas projections based on the IPCC SRES scenarios including the decline in halocarbons due to the Montreal Protocol. Specifically we investigate the impact of hydrogen releases on the oxidative capacity of the atmosphere, the long-term stability of the ozone layer due to changes in hydrogen emissions, the impact of hydrogen emissions and resulting concentrations on climate, the impact on microbial ecosystems involved in hydrogen uptake, and criteria pollutants emitted from distributed and centralized hydrogen production pathways and their impacts on human health, air quality, ecosystems, and structures under different penetration scenarios
Date: June 1, 2010
Creator: Wuebbles, D.J.; Dubey, M.K., Edmonds, J.; Layzell, D.; Olsen, S.; Rahn, T.; Rocket, A. et al.
Object Type: Report
System: The UNT Digital Library
Re-Assessing Green Building Performance: A Post Occupancy Evaluation of 22 GSA Buildings (open access)

Re-Assessing Green Building Performance: A Post Occupancy Evaluation of 22 GSA Buildings

2nd report on the performance of GSA's sustainably designed buildings. The purpose of this study was to provide an overview of measured whole building performance as it compares to GSA and industry baselines. The PNNL research team found the data analysis illuminated strengths and weaknesses of individual buildings as well as the portfolio of buildings. This section includes summary data, observations that cross multiple performance metrics, discussion of lessons learned from this research, and opportunities for future research. The summary of annual data for each of the performance metrics is provided in Table 25. The data represent 1 year of measurements and are not associated with any specific design features or strategies. Where available, multiple years of data were examined and there were minimal significant differences between the years. Individually focused post occupancy evaluation (POEs) would allow for more detailed analysis of the buildings. Examining building performance over multiple years could potentially offer a useful diagnostic tool for identifying building operations that are in need of operational changes. Investigating what the connection is between the building performance and the design intent would offer potential design guidance and possible insight into building operation strategies. The 'aggregate operating cost' metric used in …
Date: June 1, 2010
Creator: Fowler, Kimberly M.; Rauch, Emily M.; Henderson, Jordan W. & Kora, Angela R.
Object Type: Report
System: The UNT Digital Library