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METHOD OF HYPERBOLIC SYSTEMS WITH STIFF RELAXATION

Description: Three methods are analyzed for solving a linear hyperbolic system that contains stiff relaxation. We show that the semi-discrete discontinuous Galerkin method, with a linear basis, is accurate when the relaxation time is unresolved (asymptotically preserving--AP). A recently developed central method is shown to be non-AP. To discriminate between AP and non-AP methods, we argue that one must study problems that are diffusion dominated.
Date: March 1, 2001
Creator: LOWRIE, R. B. & MOREL, J. E.
Partner: UNT Libraries Government Documents Department
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Integrating Monitoring and Decision Modeling within a Cooperative Framework: Promoting Transboundary Water Management and Avoiding Regional Conflict

Description: Surface and groundwater resources do not recognize political boundaries. Where nature and boundary cross, tension over shared water resources can erupt. Such tension is exacerbated in regions where demand approaches or exceeds sustainable supplies of water. Establishing equitable management strategies can help prevent and resolve conflict over shared water resources. This paper describes a methodology for addressing transboundary water issues predicated on the integration of monitoring and modeling within a framework of cooperation. Cooperative monitoring begins with agreement by international scientists and/or policy makers on transboundary monitoring goals and strategies; it leads to the process of obtaining and sharing agreed-upon information among parties with the purpose of providing verifiable and secure data. Cooperative modeling is the process by which the parties jointly interpret the data, forecast future events and trends, and quantify cause and effect relationships. Together, cooperative monitoring and modeling allow for the development and assessment of alternative management and remediation strategies that could form the basis of regional watershed agreements or treaties. An example of how this multifaceted approach might be used to manage a shared water resource is presented for the Kura River basin in the Caucasus.
Date: March 1, 2001
Creator: Tidwell, Vincent C.; Salerno, Reynolds M.; Passell, Howard D.; Larson, Kelli L.; Kalinina, Elena Arkadievna; Wolf, Aaron T. et al.
Partner: UNT Libraries Government Documents Department
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WHITE PAPER ON PROTON - NUCLEUS COLLISONS.

Description: The role of proton-nucleus (p-A) collisions in the study of strong interactions has a long history. It has been an important testing ground for QCD. At RHIC p-A studies have been recognized since the beginning as important elements of the program. These include so-called baseline measurements in cold nuclear matter, essential (along with p-p studies) to a systematic study of QCD at high temperatures and densities in the search for the quark gluon plasma. Also accessible is a study of QCD in the small x (parton saturation) regime, complementary to physics accessible in high-energy e-p and e-A collisions. The role of p-A physics at RHIC was reviewed and brought into sharp focus at a workshop conducted in October 2000 at BNL; the agenda is shown in Appendix 1. This document summarizes the case for p-A at RHIC during the period covered by the next Nuclear Physics Long Range Plan. In subsequent sections we cover the Physics Issues, Experiment Run Plans and Schedule, Detector Upgrade Issues, and Machine Issues & Upgrades.
Date: March 1, 2001
Creator: ARONSON,S.H. & PENG,J.C.
Partner: UNT Libraries Government Documents Department
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ANALYSIS OF 3-D URBAN DATABASES WITH RESPECT TO POLLUTION DISPERSION FOR A NUMBER OF EUROPEAN AND AMERICAN CITIES

Description: Models to estimate pollution dispersion and wind flow in cities (both at the city-scale and above) require a parametrical description of the urban canopy. For instance, two key parameters are the aerodynamic roughness length z{sub 0} and the zero-plane displacement height z{sub d}, which are related, amongst others, to the surface drag coefficient, the scale and intensity of turbulence, the depth of the roughness sub-layer and the wind speed profile. The calculation of z{sub 0} and z{sub d}, however, is not straightforward. The classical way to estimate them in open terrain is based on the measurement of wind profile data from a tall mast or, less accurately, on the inference from published roughness values for similar terrain elsewhere (Davenport, 1960; Davenport et al., 2000). Both methods, however, are very difficult to apply to cities, due to the considerable height where wind measurements should be taken (well above the urban canopy) and to the irregularities of urban texture. A promising alternative that has become available in recent years, due to increasing computing resources and the availability of high-resolution 3-D databases in urban areas, is based on the calculation of z{sub 0} and z{sub d} from the analysis and measure of the city geometry (urban morphometry). This method is reviewed for instance in Grimmond and Oke (1999), where values are calculated using different formulas and then compared with the results of field measurements. Urban morphometry opens up a new range of parameters that can easily be calculated in urban areas and used as input for meso-scale and urban dispersion models. This paper reviews a number of them and shows how they could be calculated from urban Digital Elevation Models (DEM) using image-processing techniques. It builds up on the recent work by Ratti et al. 2000, extending the number of case studies cities: …
Date: March 1, 2001
Creator: RATTI, C. & AL, ET
Partner: UNT Libraries Government Documents Department
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The Clean Air Act and Renewable Energy: Opportunities, Barriers, and Options

Description: This paper examines the opportunities, obstacles, and potential options to promote renewable energy under the CAA and related programs. It deals, in sequence, with the regulation of SO2, NOx, regional haze/particulate matter, and CO2. For each pollutant, the paper discusses the opportunities, barriers, and options for boosting renewables under the CAA. It concludes by comparing the options discussed. The paper is based on a project on environmental regulation and renewable energy in electricity generation conducted by the National Renewable Energy Laboratory for the Office of Power Technologies, Office of Energy Efficiency and Renewable Energy, US Department of Energy.
Date: March 1, 2001
Creator: Wooley, D.R. (Young, Sommer, Ward, Ritzenberg, Wooley, Baker and Moore, LLC); Morss, E.M. (Young, Sommer, Ward, Ritzenberg, Wooley, Baker and Moore, LLC) & Fang, J.M. (National Renewable Energy Laboratory)
Partner: UNT Libraries Government Documents Department
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Tropospheric Aerosol Program, Program Plan, March 2001

Description: The goal of Tropospheric Aerosol Program (TAP) will be to develop the fundamental scientific understanding required to construct tools for simulating the life cycle of tropospheric aerosols--the processes controlling their mass loading, composition, and microphysical properties, all as a function of time, location, and altitude. The TAP approach to achieving this goal will be by conducting closely linked field, modeling, laboratory, and theoretical studies focused on the processes controlling formation, growth, transport, and deposition of tropospheric aerosols. This understanding will be represented in models suitable for describing these processes on a variety of geographical scales; evaluation of these models will be a key component of TAP field activities. In carrying out these tasks TAP will work closely with other programs in DOE and in other Federal and state agencies, and with the private sector. A forum to directly work with our counterparts in industry to ensure that the results of this research are translated into products that are useful to that community will be provided by NARSTO (formerly the North American Research Strategy on Tropospheric Ozone), a public/private partnership, whose membership spans government, the utilities, industry, and university researchers in Mexico, the US, and Canada.
Date: March 1, 2001
Creator: Schwartz, S. E. & Lunn, P.
Partner: UNT Libraries Government Documents Department
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Active Control of Magnetically Levitated Bearings

Description: This report summarizes experimental and test results from a two year LDRD project entitled Real Time Error Correction Using Electromagnetic Bearing Spindles. This project was designed to explore various control schemes for levitating magnetic bearings with the goal of obtaining high precision location of the spindle and exceptionally high rotational speeds. As part of this work, several adaptive control schemes were devised, analyzed, and implemented on an experimental magnetic bearing system. Measured results, which indicated precision positional control of the spindle was possible, agreed reasonably well with simulations. Testing also indicated that the magnetic bearing systems were capable of very high rotational speeds but were still not immune to traditional structural dynamic limitations caused by spindle flexibility effects.
Date: March 1, 2001
Creator: BARNEY, PATRICK S.; LAUFFER, JAMES P.; REDMOND, JAMES M. & SULLIVAN, WILLIAM N.
Partner: UNT Libraries Government Documents Department
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IN-SITU CHARACTERIZATION OF MATRIX RESPONSE TO FIBER FRACTURES

Description: Successful application of metal matrix composites often requires strength and lifetime predictions that account for the deformation of each constituent. However, the deformation of individual phases in composites usually differs significantly from their respective monolithic behaviors. For instance, generally little is known about the in-situ deformation of the metal matrix and fiber/matrix interface region, other than that it likely differs from the bulk material response. This article describes an approach to quantifying the in-situ deformation parameters using neutron diffraction measurements of matrix failure around a fiber fracture in a model composite consisting of an Al matrix and a single Al{sub 2}O{sub 3} fiber. We also study the shear sliding resistance as it evolves through fiber fracture upon loading and unloading. Matching the stress/strain distributions predicted from micromechanical models to the measured strain distributions determined by neutron diffraction under applied tensile loading results in an estimate of the typically non-linear, stress-strain behavior of the metal matrix.
Date: March 1, 2001
Creator: HANAN, J. & AL, ET
Partner: UNT Libraries Government Documents Department
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THE ORIGIN OF ALL COSMIC RAYS: A SPACE-FILLING MECHANISM

Description: There is a need for one mechanism to accelerate cosmic rays universally over the full energy spectrum, isotropically, and space filling. The current view is a theory based upon a series of mechanisms, patched to fit various spectral regions with a mechanism for the origin of the UHCRs still in doubt. We suggest that the reconnection of force-free magnetic fields produced by the twisting of all imbedded magnetic flux by the vorticity motion of all accretion or condensations both within the Galaxy as well as the metagalaxy is the universal mechanism. This leads to the acceleration of all cosmic rays with both total energy and individual energies up to the highest observed of 3 x 10{sup 20} ev and predicting an upper limit of 10{sup 23} ev. There are three primary, and we believe compelling reasons for adopting this different view of the origin of CRs. (1) The energy source is space filling and isotropic, thereby avoiding any anisotropy's due to single sources, e.g., supernovae remnants and AGN. (2) The galactic and particularly the extragalactic energy source is sufficient to supply the full energy of a universal galactic and extragalactic spectrum of 10{sup 60} to 10{sup 61} ergs sufficient to avoid the GZK cut-off. (3) Efficient E{sub parallel} acceleration from reconnection of force-free fields is well observed in the laboratory whereas collisionless shock acceleration still eludes laboratory confirmation.
Date: March 1, 2001
Creator: COLGATE, S. & LI, H.
Partner: UNT Libraries Government Documents Department
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Shaft Sinking at the Nevada Test Site, U1h Shaft Project

Description: The U1h Shaft Project is a design/build subcontract to construct one 6.1 meter (m) (20 feet (ft)) finished diameter shaft to a depth of 321.6 m (1,055 ft.) at the Nevada Test Site. Atkinson Construction was subcontracted by Bechtel Nevada to construct the U1h Shaft for the U.S. Department of Energy. The project consists of furnishing and installing the sinking plant, construction of the 321.6 m (1,055 ft.) of concrete lined shaft, development of a shaft station at a depth of 297.5 m (976 ft.), and construction of a loading pocket at the station. The outfitting of the shaft and installation of a new hoist may be incorporated into the project at a later date. This paper will describe the design phase, the excavation and lining operation, shaft station construction and the contractual challenges encountered on this project.
Date: March 1, 2001
Creator: Briggs, B. & Musick, R.
Partner: UNT Libraries Government Documents Department
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Scanning Nearfield Infrared Microscopy

Description: Commonly, location specific chemical identification by means of vibrational spectroscopy in the infrared region is largely restricted to samples of macroscopic dimensions, on the order of one to several microns; the scale of the examined area is completely determined by the diffraction limit of the incident radiation. However, chemical identification at length scales less than the diffraction limit is possible using a scanned probe technique, the Scanning Near-Field Infrared Microscope (SNFIM). Using a scanned probe technique in the near-field, resolution of chemical features on the order of h/20 or {approximately} 100 nm can be achieved. An overview of previous experimental results using a free electron laser (FEL) and more conventional infrared sources will be discussed. Recent results from the SNFIM experiment at Jefferson Lab will also be presented.
Date: March 1, 2001
Creator: Gillman, Edward
Partner: UNT Libraries Government Documents Department
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Review of Chemical Sensors for In-Situ Monitoring of Volatile Contaminants

Description: Sandia National Laboratories has sponsored an LDRD (Laboratory Directed Research and Development) project to investigate and develop micro-chemical sensors for in-situ monitoring of subsurface contaminants. As part of this project, a literature search has been conducted to survey available technologies and identify the most promising methods for sensing and monitoring subsurface contaminants of interest. Specific sensor technologies are categorized into several broad groups, and these groups are then evaluated for use in subsurface, long-term applications. This report introduces the background and specific scope of the problem being addressed by this LDRD project, and it provides a summary of the advantages and disadvantages of each sensor technology identified from the literature search.
Date: March 1, 2001
Creator: HO, CLIFFORD K.; ITAMURA, MICHAEL T.; KELLEY, MICHAEL J. & HUGHES, ROBERT C.
Partner: UNT Libraries Government Documents Department
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THE VALUE OF HELIUM-COOLED REACTOR TECHNOLOGIES OF NUCLEAR WASTE

Description: Helium-cooled reactor technologies offer significant advantages in accomplishing the waste transmutation process. They are ideally suited for use with thermal, epithermal, or fast neutron energy spectra. They can provide a relatively hard thermal neutron spectrum for transmutation of fissionable materials such as Pu-239 using ceramic-coated transmutation fuel particles, a graphite moderator, and a non-fertile burnable poison. These features (1) allow deep levels of transmutation with minimal or no intermediate reprocessing, (2) enhance passive decay heat removal via heat conduction and radiation, (3) allow operation at relatively high temperatures for a highly efficient generation of electricity, and (4) discharge the transmuted waste in a form that is highly resistant to corrosion for long times. They also offer the possibility for the use of epithermal neutrons that can interact with transmutable materials more effectively because of the large atomic cross sections in this energy domain. A fast spectrum may be useful for deep burnup of certain minor actinides. For this application, helium is essentially transparent to neutrons, does not degrade neutron energies, and offers the hardest possible neutron energy environment. In this paper, we report results from recent work on materials transmutation balances, safety, value to a geological repository, and economic considerations.
Date: March 1, 2001
Creator: RODRIGUEZ, C. & BAXTER, A.
Partner: UNT Libraries Government Documents Department
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SEPARATION OF CO2 FROM FLUE GASES BY CARBON-MULTIWALL CARBON NANOTUBE MEMBRANES

Description: Multiwalled carbon nanotubes (MWNT) were found to be an effective separation media for removing CO{sub 2} from N{sub 2}. The separation mechanism favors the selective condensation of CO{sub 2} from the flowing gas stream. Significant uptakes of CO{sub 2} were measured at 30 C and 150 C over the pressure range 0.5 to 5 bar. No measurable uptake of nitrogen was found for this range of conditions. The mass uptake of CO{sub 2} by MWNT was found to increase with increasing temperature. A packed bed of MWNT completely removed CO{sub 2} from a flowing stream of CO{sub 2}/N{sub 2}, and exhibited rapid uptake kinetics for CO{sub 2}.
Date: March 1, 2001
Creator: Andrews, Rodney
Partner: UNT Libraries Government Documents Department
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WELD APPLICATION OF A NEW METHOD FOR CROSS-SECTIONAL RESIDUAL STRESS MAPPING

Description: The new ''contour method'' was used to measure a cross-sectional map of residual stresses in a welded plate. Comparisons with neutron diffraction measurements confirm the capability of the contour method to measure complex, 2-D stress maps. Compared to other methods, the contour method is relatively simple and inexpensive to perform, and the equipment required is widely available.
Date: March 1, 2001
Creator: PRIME, M. & AL, ET
Partner: UNT Libraries Government Documents Department
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Adding static printing capabilities to the EUV phase-shifting point diffraction interferometer

Description: While interferometry is routinely used for the characterization and alignment of lithographic optics, the ultimate performance metric for these optics is printing in photoresist. Direct comparison of imaging and wavefront performance is also useful for verifying and improving the predictive power of wavefront metrology under actual printing conditions. To address these issues, static, small-field printing capabilities are being added to the extreme ultraviolet (EUV) phase-shifting point diffraction interferometer (PS/PDI) implemented at the Advanced Light Source at Lawrence Berkeley National Laboratory. This Sub-field Exposure Station (SES) will enable the earliest possible imaging characterization of the upcoming Engineering Test Stand (ETS) Set-2 projection optics. Relevant printing studies with the ETS projection optics require illumination partial coherence with {sigma} of approximately 0.7. This {sigma} value is very different from the coherent illumination requirements of the EUV PS/PDI and the coherence properties naturally provided by synchrotron undulator beamline illumination. Adding printing capabilities to the PS/PDI experimental system thus necessitates the development of an alternative illumination system capable of destroying the inherent coherence of the beamline. The SES is being implemented with two independent illuminators: the first is based on a novel EUV diffuser currently under development and the second is based on a scanning mirror design. Here we describe the design and implementation of the new SES, including a discussion of the illuminators and the fabrication of the EUV diffuser.
Date: March 1, 2001
Creator: Naulleau, Patrick; Goldberg, Kenneth A.; Anderson, Erik H.; Batson, Phillip; Denham, Paul; Jackson, Keith et al.
Partner: UNT Libraries Government Documents Department
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A COMPARISON OF FOUR METHODS FOR DETERMINING PRECIPITABLE WATER VAPOR CONTENT FROM MULTI-SPECTRAL DATA

Description: Determining columnar water vapor is a fundamental problem in remote sensing. This measurement is important both for understanding atmospheric variability and also from removing atmospheric effects from remotely sensed data. Therefore discovering a reliable and if possible automated method for determining water vapor column abundance is important. There are two standard methods for determining precipitable water vapor during the daytime from multi-spectral data. The first method is the Continuum Interpolated Band Ratio (CIBR) (see for example King et al. 1996). This method assumes a baseline and measures the depth of a water vapor feature as compared to this baseline. The second method is the Atmospheric Pre-corrected Differential Absorption technique (APDA) (see Schlaepfer et al. 1998); this method accounts for the path radiance contribution to the top of atmosphere radiance measurement which is increasingly important at lower and lower reflectance values. We have also developed two methods of modifying CIBR. We use a simple curve fitting procedure to account for and remove any systematic errors due to low reflectance while still preserving the random spread of the CIBR values as a function of surface reflectance. We also have developed a two-dimensional look-up table for CIBR; CIBR using this technique is a function of both water vapor (as with all CIBR techniques) and surface reflectance. Here we use data recently acquired with the Multi-spectral Thermal Imager spacecraft (MTI) to compare these four methods of determining columnar water vapor content.
Date: March 1, 2001
Creator: HIRSCH, K. & AL, ET
Partner: UNT Libraries Government Documents Department
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Equilibrium and Nonequilibrium Foundations of Free Energy Computational Methods

Description: Statistical mechanics provides a rigorous framework for the numerical estimation of free energy differences in complex systems such as biomolecules. This paper presents a brief review of the statistical mechanical identities underlying a number of techniques for computing free energy differences. Both equilibrium and nonequilibrium methods are covered.
Date: March 1, 2001
Creator: Jarzynski, C.
Partner: UNT Libraries Government Documents Department
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Indoor Air Nuclear, Biological, and Chemical Health Modeling and Assessment System

Description: Indoor air quality effects on human health are of increasing concern to public health agencies and building owners. The prevention and treatment of 'sick building' syndrome and the spread of air-borne diseases in hospitals, for example, are well known priorities. However, increasing attention is being directed to the vulnerability of our public buildings/places, public security and national defense facilities to terrorist attack or the accidental release of air-borne biological pathogens, harmful chemicals, or radioactive contaminants. The Indoor Air Nuclear, Biological, and Chemical Health Modeling and Assessment System (IA-NBC-HMAS) was developed to serve as a health impact analysis tool for use in addressing these concerns. The overall goal was to develop a user-friendly fully functional prototype Health Modeling and Assessment system, which will operate under the PNNL FRAMES system for ease of use and to maximize its integration with other modeling and assessment capabilities accessible within the FRAMES system (e.g., ambient air fate and transport models, water borne fate and transport models, Physiologically Based Pharmacokinetic models, etc.). The prototype IA-NBC-HMAS is designed to serve as a functional Health Modeling and Assessment system that can be easily tailored to meet specific building analysis needs of a customer. The prototype system was developed and tested using an actual building (i.e., the Churchville Building located at the Aberdeen Proving Ground) and release scenario (i.e., the release and measurement of tracer materials within the building) to ensure realism and practicality in the design and development of the prototype system. A user-friendly ''demo'' accompanies this report to allow the reader the opportunity for a ''hands on'' review of the prototype system's capability.
Date: March 1, 2001
Creator: Stenner, Robert D; Hadley, Donald L; Armstrong, Peter R; Buck, John W & Hoopes, Bonnie L
Partner: UNT Libraries Government Documents Department
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THE COLOR DIPOLE APPROACH TO THE DRELL-YAN PROCESS IN PA COLLISIONS

Description: In the target rest frame and at high energies, Drell-Yan (DY) dilepton production looks like bremsstrahlung of massive photons, rather than parton annihilation. The projectile quark is decomposed into a series of Fock states. Configurations with fixed transverse separations are interaction eigenstates for pp scattering. The DY cross section can then be expressed in terms of the same color dipole cross section as DIS. This approach is especially suitable to describe nuclear effects, since it allows to apply Glauber multiple scattering theory. We go beyond the Glauber eikonal approximation by taking into account transitions between interaction eigenstates. We calculate nuclear shadowing at large Feynman-x{sub f} for DY in proton-nucleus collisions, compare to existing data from E772 and make predictions for RHIC. Nuclear effects on the transverse momentum distribution are also investigated.
Date: March 1, 2001
Creator: KOPELIOVICH, B. & AL, ET
Partner: UNT Libraries Government Documents Department
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