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Establishing Ergonomics in Industrially Developing Countries (open access)

Establishing Ergonomics in Industrially Developing Countries

The introduction of ergonomics is an ongoing effort in industrially developing countries and will ultimately require an organized, programmatic approach spanning several countries and organizations. Our preliminary efforts with our partner countries of Viet Nam, Thailand, and Nicaragua have demonstrated that a one-time course is just the first step in a series of necessary events to provide skills and create an infrastructure that will have lasting impact for the host country. To facilitate that any sort of training has a lasting impact, it is recommended that host countries establish a 'contract' with class participants and the guest instructors for at least one follow-up visit so instructors can see the progress and support the participants in current and future efforts. With repeated exchanges, the class participants can become the 'in country experts' and the next generation of ergonomic trainers. Additionally, providing participants with an easy to use hazard assessment tool and methods for evaluating the financial impact of the project (cost/benefit analysis) will assist increase the likelihood of success and establish a foundation for future projects. In the future, developing trade and regionally/culturally specific 'ergonomics toolkits' can help promote broader implementation, especially where training resources may be limited.
Date: August 29, 2005
Creator: Stewart, K.; Silverstein, B. & Kiefer, M.
System: The UNT Digital Library
CONFERENCE PROPOSAL: “Time-Resolved Vibrational Spectroscopy XII” (open access)

CONFERENCE PROPOSAL: “Time-Resolved Vibrational Spectroscopy XII”

None
Date: August 29, 2005
Creator: Heilweil, Edwin J. & Gustafson, Terry L.
System: The UNT Digital Library
Quantum-based Atomistic Simulation of Transition Metals (open access)

Quantum-based Atomistic Simulation of Transition Metals

First-principles generalized pseudopotential theory (GPT) provides a fundamental basis for transferable multi-ion interatomic potentials in d-electron transition metals within density-functional quantum mechanics. In mid-period bcc metals, where multi-ion angular forces are important to structural properties, simplified model GPT or MGPT potentials have been developed based on canonical d bands to allow analytic forms and large-scale atomistic simulations. Robust, advanced-generation MGPT potentials have now been obtained for Ta and Mo and successfully applied to a wide range of structural, thermodynamic, defect and mechanical properties at both ambient and extreme conditions of pressure and temperature. Recent algorithm improvements have also led to a more general matrix representation of MGPT beyond canonical bands allowing increased accuracy and extension to f-electron actinide metals, an order of magnitude increase in computational speed, and the current development of temperature-dependent potentials.
Date: August 29, 2005
Creator: Moriarty, J A; Benedict, L X; Glosli, J N; Hood, R Q; Orlikowski, D A; Patel, M V et al.
System: The UNT Digital Library
Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-ray Preheat (open access)

Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-ray Preheat

To drive shocks into solids with a laser we either illuminate the material directly, or to get higher pressures, illuminate a plastic ablator that overlays the material of interest. In both cases the illumination intensity is low, <<10{sup 13} W/cm{sup 2}, compared to that for traditional laser fusion targets. In this regime, the laser beam creates and interacts with a collisional, rather than a collisionless, plasma. We present scaling relationships for shock pressure with intensity derived from simulations for this low-intensity collisional plasma regime. In addition, sometimes the plastic-ablator targets have a thin flashcoating of Al on the plastic surface as a shine-through barrier; this Al layer can be a source of hot x-ray preheat. We discuss how the preheat affects the shock pressure, with application to simulating VISAR measurements from experiments conducted on various lasers on shock compression of Fe.
Date: August 29, 2005
Creator: Colvin, J D & Kalantar, D H
System: The UNT Digital Library
A Hybrid approach to molecular continuum processes combining Gaussian basis functions and the discrete variable representation (open access)

A Hybrid approach to molecular continuum processes combining Gaussian basis functions and the discrete variable representation

Gaussian basis functions, routinely employed in molecular electronic structure calculations, can be combined with numerical grid-based functions in a discrete variable representation to provide an efficient method for computing molecular continuum wave functions. This approach, combined with exterior complex scaling, obviates the need for slowly convergent single-center expansions, and allows one to study a variety of electron-molecule collision problems. The method is illustrated by computation of various bound and continuum properties of H2+.
Date: August 29, 2005
Creator: Rescigno, Thomas N.; Horner, Daniel A.; Yip, Frank L. & McCurdy, C. William
System: The UNT Digital Library
HYDROLASING OF CONTAMINATED UNDERWATER BASIN SURFACES AT THE HANFORD K-AREA (open access)

HYDROLASING OF CONTAMINATED UNDERWATER BASIN SURFACES AT THE HANFORD K-AREA

None
Date: August 29, 2005
Creator: Chronister, G. B. & Umek, A. M.
System: The UNT Digital Library
THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) REFRIGERATOR SYSTEM AT BROOKHAVEN NATIONAL LABORATORY: PHASE III OF THE SYSTEM PERFORMANCE AND OPERATIONS UPGRADES FOR 2003 (open access)

THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) REFRIGERATOR SYSTEM AT BROOKHAVEN NATIONAL LABORATORY: PHASE III OF THE SYSTEM PERFORMANCE AND OPERATIONS UPGRADES FOR 2003

An ongoing program at Brookhaven National Laboratory (BNL) consists of improving the efficiency of the Relativistic Heavy Ion Collider (RHIC) cryogenic system and reducing its power consumption. Phase I and I1 of the program addressed plant operational improvements and modifications that resulted in substantial operational cost reduction and improved system reliability and stability, and a compressor input power reduction of 2 MW has been demonstrated. Phase 111, now under way, consists of plans for further increasing the efficiency of the plant by adding a load ''wet'' turbo-expander and its associated heat exchangers at the low temperature end of the plant. This additional stage of cooling at the coldest level will further reduce the required compressor flow and therefore compressor power input. This paper presents the results of the plant characterization, as it is operating presently, as well as the results of the plant simulations of the various planned upgrades for, the plant. The immediate upgrade includes the changes associated with the load expander. The subsequent upgrade will involve the resizing of expander 5 and 6 to increase their efficiencies. The paper summarizes the expected improvement in the plant efficiency and the overall reduction in the compressor power.
Date: August 29, 2005
Creator: Sidi-Yekhlef, A.; Tuozzolo, J.; Than, R.; Knudsen, P. & Arenius, D.
System: The UNT Digital Library
The NIF: Path to Ignition in the laboratory (open access)

The NIF: Path to Ignition in the laboratory

The National Ignition Facility (NIF) is a 192-beam, 1.8-MJ, 500-TW ultraviolet laser facility presently under construction at LLNL for inertial confinement fusion (ICF) ignition and high energy density (HED) experiments. Four of the NIF beams were commissioned to demonstrate laser performance. On a single-beam basis NIF has shown that it meets its performance goals and demonstrated its precision and flexibility for pulse shaping, pointing, timing and beam conditioning. Four experiments were also performed for ICF and HED science. Presently, the project is installing production hardware to complete the project in 2009 with the goal to begin ignition experiments in 2010. An integrated plan has been developed including the NIF operations, user equipment such as diagnostics and cryogenic target capability, experiments, and calculations to meet this goal.
Date: August 29, 2005
Creator: Moses, Edward
System: The UNT Digital Library
Modified borohydrides for reversible hydrogen storage (open access)

Modified borohydrides for reversible hydrogen storage

In attempt to develop lithium borohydrides as the reversible hydrogen storage materials with the high capacity, the feasibility to reduce dehydrogenation temperature of the lithium borohydride and moderate rehydrogenation condition has been explored. The commercial available lithium borohydride has been modified by ball milling with metal oxides and metal chlorides as the additives. The modified lithium borohydrides release 9 wt% hydrogen starting from 473K. The dehydrided modified lithium borohydrides absorb 7-9 wt% hydrogen at 873K and 7 MPa. The additive modification reduces dehydriding temperature from 673K to 473K and moderates rehydrogenation conditions to 923K and 15 MPa. XRD and SEM analysis discovered the formation of the intermediate compound TiB{sub 2} that may plays the key role in change the reaction path resulting the lower dehydriding temperature and reversibility. The reversible hydrogen storage capacity of the oxide modified lithium borohydrides decreases gradually during hydriding-dehydriding cycling due to the lost of the boron during dehydrogenation. But, it can be prevented by selecting the suitable additive, forming intermediate boron compounds and changing the reaction path. The additives reduce dehydriding temperature and improve the reversibility, it also reduces the hydrogen storage capacity. The best compromise can be reached by optimization of the additive loading …
Date: August 29, 2005
Creator: Au, Ming
System: The UNT Digital Library
Water Under the Extreme Conditions of Planetary Interiors: Symmetric Hydrogen Bonding in the Superionic Phase (open access)

Water Under the Extreme Conditions of Planetary Interiors: Symmetric Hydrogen Bonding in the Superionic Phase

The predicted superionic phase of water is investigated via ab initio molecular dynamics at densities of 2.0-3.0 g/cc (34 -115 GPa) along the 2000K isotherm.We find that extremely rapid (superionic) diffusion of protons occurs in a fluid phase at pressures between 34 and 58 GPa. A transition to a stable body-centered cubic (bcc) O lattice with superionic proton conductivity is observed between 70 and 75 GPa, a much higher pressure than suggested in prior work. We find that all molecular species at pressures greater than 75 GPa are too short lived to be classified as bound states. Above 95 GPa, a transient network phase is found characterized by symmetric O-H hydrogen bonding with nearly 50% covalent character.
Date: August 29, 2005
Creator: Goldman, N & Fried, L E
System: The UNT Digital Library
A Precise Sum Rule among Four B -> K pi CP Asymmetries (open access)

A Precise Sum Rule among Four B -> K pi CP Asymmetries

A sum rule relation is proposed for direct CP asymmetries in B {yields} K{pi} decays. Leading terms are identical in the isospin symmetry limit, while subleading terms are equal in the flavor SU(3) and heavy quark limits. The sum rule predicts A{sub CP}(B{sup 0} {yields} K{sup 0}{pi}{sup 0}) = -0.17 {+-} 0.06 using current asymmetry measurements for the other three B {yields} K{pi} decays. A violation of the sum rule would be evidence for New Physics in b {yields} s{bar q}q transitions.
Date: August 29, 2005
Creator: Gronau, Michael & /Technion, /SLAC
System: The UNT Digital Library
Recent BaBar Results on Hadron Spectroscopy (open access)

Recent BaBar Results on Hadron Spectroscopy

Recent results from on hadronic spectroscopy are presented, based on data collected by the BaBar experiment between 1999 and 2004. The properties of the recently discovered D*{sub sJ}(2317){sup +} and D{sub sJ}(2460){sup +} states are studied: resonance parameters and ratios of decay rates are measured from continuum e{sup +}e{sup -} production, and production rates are measured from B decays. A search for the D*{sub sJ}(2632){sup +} state whose observation has been recently reported by the SELEX Collaboration, and a search for a charged partner of the charmonium-like X(3872) state, are performed, yielding negative results. Finally, extensive searches for several pentaquark candidates, both fully inclusive and in B decays, result in no positive evidence.
Date: August 29, 2005
Creator: Robutti, E. & /INFN, Genoa
System: The UNT Digital Library
Application of Sequence-based Methods in Human MicrobialEcology (open access)

Application of Sequence-based Methods in Human MicrobialEcology

Ecologists studying microbial life in the environment have recognized the enormous complexity of microbial diversity for many years, and the development of a variety of culture-independent methods, many of them coupled with high-throughput DNA sequencing, has allowed this diversity to be explored in ever greater detail. Despite the widespread application of these new techniques to the characterization of uncultivated microbes and microbial communities in the environment, their application to human health and disease has lagged behind. Because DNA based-techniques for defining uncultured microbes allow not only cataloging of microbial diversity, but also insight into microbial functions, investigators are beginning to apply these tools to the microbial communities that abound on and within us, in what has aptly been called the second Human Genome Project. In this review we discuss the sequence-based methods for microbial analysis that are currently available and their application to identify novel human pathogens, improve diagnosis of known infectious diseases, and to advance understanding of our relationship with microbial communities that normally reside in and on the human body.
Date: August 29, 2005
Creator: Weng, Li; Rubin, Edward M. & Bristow, James
System: The UNT Digital Library
Current Status of Deep Geological Repository Development (open access)

Current Status of Deep Geological Repository Development

This talk provided an overview of the current status of deep-geological-repository development worldwide. Its principal observation is that a broad consensus exists internationally that deep-geological disposal is the only long-term solution for disposition of highly radioactive nuclear waste. Also, it is now clear that the institutional and political aspects are as important as the technical aspects in achieving overall progress. Different nations have taken different approaches to overall management of their highly radioactive wastes. Some have begun active programs to develop a deep repository for permanent disposal: the most active such programs are in the United States, Sweden, and Finland. Other countries (including France and Russia) are still deciding on whether to proceed quickly to develop such a repository, while still others (including the UK, China, Japan) have affirmatively decided to delay repository development for a long time, typically for a generation of two. In recent years, a major conclusion has been reached around the world that there is very high confidence that deep repositories can be built, operated, and closed safely and can meet whatever safety requirements are imposed by the regulatory agencies. This confidence, which has emerged in the last few years, is based on extensive work around …
Date: August 29, 2005
Creator: Budnitz, R. J.
System: The UNT Digital Library
Hadron Physics in BaBar (open access)

Hadron Physics in BaBar

Some recent results in hadron physics from the BaBar experiment are discussed. In particular, the observation of two new charmed states, the D*{sub sJ}{sup +}(2317) and the D*{sub sJ}{sup +}(2457), is described, and results are presented on the first measurement of the rare decay mode of the B meson, B{sup 0} {pi}{sup 0}{pi}{sup 0}.
Date: August 29, 2005
Creator: Lafferty, G.D.
System: The UNT Digital Library
K-(alpha) Radiography at 20-100 keV Using Short-Pulse Lasers (open access)

K-(alpha) Radiography at 20-100 keV Using Short-Pulse Lasers

X-ray radiography is an important tool for diagnosing and imaging planar and convergent hydrodynamics phenomena for laser experiments. Until now, hydrodynamics experiments at Omega and NIF utilize E{sub x-ray} < 9 keV backlighter x-rays emitted by thermal plasmas. However, future experiments will need to diagnose larger and denser targets and will require x-ray probes of energies from 20-100 keV and possibly up to 1 MeV. Hard K-{alpha} x-ray photons can be created through high-energy electron interactions in the target material after irradiation by petawatt-class high-intensity-short-pulse lasers with > 10{sup 17} W/cm{sup 2}. We have performed several experiments on the JanUSP, and the Vulcan 100TW, and Vulcan Petawatt lasers to understand K-{alpha} sources and to test radiography concepts. 1-D radiography using an edge-on foil and 2-D radiography using buried wires and cone-fiber targets were tested. We find that 1-D thin edge-on foils can have imaging resolution better than 10 {micro}m. Micro volume targets produce bright sources with measured conversion efficiency from laser energy to x-ray photons of {approx} 1 x 10{sup -5}. This level of conversion may not be enough for 2-D point projection radiography. A comparison of our experimental measurements of small volume sources with the LSP/PIC simulation show similar …
Date: August 29, 2005
Creator: Park, H. S.; Chambers, D.; Clarke, R.; Eagleton, R.; Giraldez, E.; Goldsack, T. et al.
System: The UNT Digital Library
Prediction of coherent optical radiation from shock waves in polarizable crystals (open access)

Prediction of coherent optical radiation from shock waves in polarizable crystals

We predict that coherent electromagnetic radiation in the 1-100 THz frequency range can be generated in crystalline materials when subject to a shock wave or soliton-like propagating excitation. To our knowledge, this phenomenon represents a fundamentally new form of coherent optical radiation source that is distinct from lasers and free-electron lasers. General analytical theory and molecular dynamics simulations demonstrate coherence lengths on the order of mm (around 20 THz) and potentially greater. The emission frequencies are determined by the shock speed and the lattice constants of the crystal and can potentially be used to determine atomic-scale properties of the shocked material.
Date: August 29, 2005
Creator: Reed, E J; Soljacic, M; Gee, R & Joannopoulos, J D
System: The UNT Digital Library
Liquid Hydrogen Target Experience at SLAC (open access)

Liquid Hydrogen Target Experience at SLAC

Liquid hydrogen targets have played a vital role in the physics program at SLAC for the past 40 years. These targets have ranged from small ''beer can'' targets to the 1.5 m long E158 target that was capable of absorbing up to 800 W without any significant density changes. Successful use of these targets has required the development of thin wall designs, liquid hydrogen pumps, remote positioning and alignment systems, safety systems, control and data acquisition systems, cryogenic cooling circuits and heat exchangers. Detailed operating procedures have been created to ensure safety and operational reliability. This paper surveys the evolution of liquid hydrogen targets at SLAC and discusses advances in several of the enabling technologies that made these targets possible.
Date: August 29, 2005
Creator: Weisend, J. G.; Boyce, R.; Candia, A.; Kaminskas, W.; Mark, J.; Racine, M. et al.
System: The UNT Digital Library