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Approximating conductive ellipsoid inductive responses using static quadrupole moments (open access)

Approximating conductive ellipsoid inductive responses using static quadrupole moments

Smith and Morrison (2006) developed an approximation for the inductive response of conducting magnetic (permeable) spheroids (e.g., steel spheroids) based on the inductive response of conducting magnetic spheres of related dimensions. Spheroids are axially symmetric objects with elliptical cross-sections along the axis of symmetry and circular cross sections perpendicular to the axis of symmetry. Spheroids are useful as an approximation to the shapes of unexploded ordnance (UXO) for approximating their responses. Ellipsoids are more general objects with three orthogonal principal axes, with elliptical cross sections along planes normal to the axes. Ellipsoids reduce to spheroids in the limiting case of ellipsoids with cross-sections that are in fact circles along planes normal to one axis. Parametrizing the inductive response of unknown objects in terms of the response of an ellipsoid is useful as it allows fitting responses of objects with no axis of symmetry, in addition to fitting the responses of axially symmetric objects. It is thus more appropriate for fitting the responses of metal scrap to be distinguished electromagnetically from unexploded ordnance. Here the method of Smith and Morrison (2006) is generalized to the case of conductive magnetic ellipsoids, and a simplified form used to parametrize the inductive response of …
Date: October 1, 2008
Creator: Smith, J. Torquil
Object Type: Report
System: The UNT Digital Library
Residual phase noise measurements of the input section in a receiver (open access)

Residual phase noise measurements of the input section in a receiver

If not designed properly, the input section of an analog down-converter can introduce phase noise that can prevail over other noise sources in the system. In the paper we present residual phase noise measurements of a simplified input section of a classical receiver that is composed of various commercially available mixers and driven by an LO amplifier.
Date: October 1, 2007
Creator: Mavric, Uros & Chase, Brian
Object Type: Article
System: The UNT Digital Library
Lifetime Difference and CP Asymmetry in the Bs -> J/psi phi decay (open access)

Lifetime Difference and CP Asymmetry in the Bs -> J/psi phi decay

The B{sub s} meson is an interesting particle to study because a sizable mixing induced CP violation in the B{sub s} -- {bar B}{sub s} system would be an indication for physics beyond the Standard Model. In this paper we present a measurement of the lifetime difference {Delta}{Gamma} between the B{sub s} mass eigenstates and the CP violating phase in the decay B{sub s} {yields} J/{psi}{phi}. In 1.7 fb{sup -1} of data collected with the CDF II detector at the Tevatron p{bar p} collider we measure {Delta}{Gamma} = 0.076{sup +0.059}{sub -0.063} (stat.) {+-}0.006 (syst.) ps{sup -1}, well consistent with the Standard Model prediction, and a mean B{sub s} lifetime of c{sub tau}{sub s} = 456 {+-} 13 (stat.) {+-} (syst.) {micro}m. We find no evidence for CP violation.
Date: October 1, 2007
Creator: Kuhr, Thomas
Object Type: Article
System: The UNT Digital Library
Distributed micro-releases of bioterror pathogens : threat characterizations and epidemiology from uncertain patient observables. (open access)

Distributed micro-releases of bioterror pathogens : threat characterizations and epidemiology from uncertain patient observables.

Terrorist attacks using an aerosolized pathogen preparation have gained credibility as a national security concern since the anthrax attacks of 2001. The ability to characterize the parameters of such attacks, i.e., to estimate the number of people infected, the time of infection, the average dose received, and the rate of disease spread in contemporary American society (for contagious diseases), is important when planning a medical response. For non-contagious diseases, we address the characterization problem by formulating a Bayesian inverse problem predicated on a short time-series of diagnosed patients exhibiting symptoms. To keep the approach relevant for response planning, we limit ourselves to 3.5 days of data. In computational tests performed for anthrax, we usually find these observation windows sufficient, especially if the outbreak model employed in the inverse problem is accurate. For contagious diseases, we formulated a Bayesian inversion technique to infer both pathogenic transmissibility and the social network from outbreak observations, ensuring that the two determinants of spreading are identified separately. We tested this technique on data collected from a 1967 smallpox epidemic in Abakaliki, Nigeria. We inferred, probabilistically, different transmissibilities in the structured Abakaliki population, the social network, and the chain of transmission. Finally, we developed an individual-based …
Date: October 1, 2008
Creator: Wolf, Michael M. (University of Illinois, Urbana-Champaign, Urbana, IL); Marzouk, Youssef M.; Adams, Brian M.; Devine, Karen Dragon; Ray, Jaideep & Najm, Habib N.
Object Type: Report
System: The UNT Digital Library
Theoretical Studies in Heterogenous Catalysis: Towards a Rational Design of Novel Catalysts for Hydrodesulfurization and Hydrogen Production (open access)

Theoretical Studies in Heterogenous Catalysis: Towards a Rational Design of Novel Catalysts for Hydrodesulfurization and Hydrogen Production

Traditionally, knowledge in heterogeneous catalysis has come through empirical research. Nowadays, there is a clear interest to change this since millions of dollars in products are generated every year in the chemical and petrochemical industries through catalytic processes. To obtain a fundamental knowledge of the factors that determine the activity of heterogeneous catalysts is a challenge for modern science since many of these systems are very complex in nature. In principle, when a molecule adsorbs on the surface of a heterogeneous catalyst, it can interact with a large number of bonding sites. It is known that the chemical properties of these bonding sites depend strongly on the chemical environment around them. Thus, there can be big variations in chemical reactivity when going from one region to another in the surface of a heterogeneous catalyst. A main objective is to understand how the structural and electronic properties of a surface affect the energetics for adsorption processes and the paths for dissociation and chemical reactions. In recent years, advances in instrumentation and experimental procedures have allowed a large series of detailed works on the surface chemistry of heterogeneous catalysts. In many cases, these experimental studies have shown interesting and unique phenomena. Theory …
Date: October 1, 2008
Creator: Rodriguez,J.A. & Liu, P.
Object Type: Book
System: The UNT Digital Library
The CMS dataset bookkeeping service (open access)

The CMS dataset bookkeeping service

The CMS Dataset Bookkeeping Service (DBS) has been developed to catalog all CMS event data from Monte Carlo and Detector sources. It provides the ability to identify MC or trigger source, track data provenance, construct datasets for analysis, and discover interesting data. CMS requires processing and analysis activities at various service levels and the DBS system provides support for localized processing or private analysis, as well as global access for CMS users at large. Catalog entries can be moved among the various service levels with a simple set of migration tools, thus forming a loose federation of databases. DBS is available to CMS users via a Python API, Command Line, and a Discovery web page interfaces. The system is built as a multi-tier web application with Java servlets running under Tomcat, with connections via JDBC to Oracle or MySQL database backends. Clients connect to the service through HTTP or HTTPS with authentication provided by GRID certificates and authorization through VOMS. DBS is an integral part of the overall CMS Data Management and Workflow Management systems.
Date: October 1, 2007
Creator: Afaq, Anzar,; /Fermilab; Dolgert, Andrew; /Cornell U., Phys. Dept.; Guo, Yuyi; /Fermilab et al.
Object Type: Article
System: The UNT Digital Library
Addendum to the Closure Report for Corrective Action Unit 358: Areas 18, 19, 20 Cellars/Mud Pits Nevada Test Site, Nevada (open access)

Addendum to the Closure Report for Corrective Action Unit 358: Areas 18, 19, 20 Cellars/Mud Pits Nevada Test Site, Nevada

This document constitutes an addendum to the January 2004, Closure Report for Corrective Action Unit 358: Areas 18, 19, 20 Cellars/Mud Pits as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • This cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the cancellation of the URs for: • CAS 20-23-02, Postshot Cellar • CAS 20-23-03, Cellar • CAS 20-23-04, Postshot Cellar • CAS 20-23-05, Postshot Cellar • CAS 20-23-06, Cellar • CAS 20-37-01, Cellar & Mud Pit • CAS 20-37-05, Cellar These URs were established as part of Federal Facility Agreement and Consent Order …
Date: October 1, 2008
Creator: Kidman, Lynn
Object Type: Report
System: The UNT Digital Library

Multi-Scale Multi-Dimensional Li-Ion Battery Model for Better Design and Management

The developed model used is to provide a better understanding and help answer engineering questions about improving the design, operational strategy, management, and safety of cells.
Date: October 1, 2008
Creator: Kim, G.-H. & Smith, K.
Object Type: Presentation
System: The UNT Digital Library
Visualization of Trajectories of Electron Beams Emitted by an IonSource with Closed Electron Drift (open access)

Visualization of Trajectories of Electron Beams Emitted by an IonSource with Closed Electron Drift

Trajectories of electron beams emitted by an ion source with an anode layer and Hall electron closed drift orbits were visualized using light emission from a working gas excited by electrons. Gas discharge of magnetron type, arising in the beam drift region under the influence of an electric field of a target bias potential, was visualized.
Date: October 1, 2007
Creator: Institue of Physics, National Academy of Sciences of Ukraine; Brown, Ian G.; Bordenjuk, Ian V.; Panchenko, Oleg A.; Sologub, Sergei V. & Brown, Ian G.
Object Type: Article
System: The UNT Digital Library
ACCURACY OF CO2 SENSORS (open access)

ACCURACY OF CO2 SENSORS

Are the carbon dioxide (CO2) sensors in your demand controlled ventilation systems sufficiently accurate? The data from these sensors are used to automatically modulate minimum rates of outdoor air ventilation. The goal is to keep ventilation rates at or above design requirements while adjusting the ventilation rate with changes in occupancy in order to save energy. Studies of energy savings from demand controlled ventilation and of the relationship of indoor CO2 concentrations with health and work performance provide a strong rationale for use of indoor CO2 data to control minimum ventilation rates1-7. However, this strategy will only be effective if, in practice, the CO2 sensors have a reasonable accuracy. The objective of this study was; therefore, to determine if CO2 sensor performance, in practice, is generally acceptable or problematic. This article provides a summary of study methods and findings ? additional details are available in a paper in the proceedings of the ASHRAE IAQ?2007 Conference8.
Date: October 1, 2008
Creator: Fisk, William J.; Faulkner, David & Sullivan, Douglas P.
Object Type: Article
System: The UNT Digital Library
Measurement of tritium permeation in flibe (2LiF•BeF2) (open access)

Measurement of tritium permeation in flibe (2LiF•BeF2)

This paper reports on the experimental investigation of tritium permeation in flibe (2LiF-BeF2) at the Safety and Tritium Applied Research facility of the Idaho National Laboratory. A stainless steel cell formed by two independent volumes separated by a 2mm thick nickel membrane is maintained at temperatures between 500 and 700 degrees Celsius. A controlled amount of T2 gas is flown in excess of argon in the source volume in contact with the bottom side of the nickel membrane, while a layer of molten salt is in contact with the top side. The tritium permeating above the liquid surface is carried by an argon flow to a diagnostic system comprised of a quadrupole mass spectrometer, a gas chromatographer and a proportional counter. Tritium permeability in flibe as a function of temperature is determined by the measured permeation flow rates reached in steady-state conditions, while the diffusivity is determined by fitting the transient process with the analytical solution for the diffusion process. As a result, the solubility of tritium in flibe as a function of temperature is also determined.
Date: October 1, 2007
Creator: Calderoni, P.; Sharpe, P.; Hara, M. & Oya, Y.
Object Type: Article
System: The UNT Digital Library
Fabrication of large-volume, low-cost ceramic lanthanum halide scintillators for gamma ray detection : final report for DHS/DNDO/TRDD project TA-01-SL01. (open access)

Fabrication of large-volume, low-cost ceramic lanthanum halide scintillators for gamma ray detection : final report for DHS/DNDO/TRDD project TA-01-SL01.

This project uses advanced ceramic processes to fabricate large, optical-quality, polycrystalline lanthanum halide scintillators to replace small single crystals produced by the conventional Bridgman growth method. The new approach not only removes the size constraint imposed by the growth method, but also offers the potential advantages of both reducing manufacturing cost and increasing production rate. The project goal is to fabricate dense lanthanum halide ceramics with a preferred crystal orientation by applying texture engineering and solid-state conversion to reduce the thermal mechanical stress in the ceramic and minimize scintillation light scattering at grain boundaries. Ultimately, this method could deliver the sought-after high sensitivity and <3% energy resolution at 662 keV of lanthanum halide scintillators and unleash their full potential for advanced gamma ray detection, enabling rapid identification of radioactive materials in a variety of practical applications. This report documents processing details from powder synthesis, seed particle growth, to final densification and texture development of cerium doped lanthanum bromide (LaBr{sub 3}:Ce{sup +3}) ceramics. This investigation demonstrated that: (1) A rapid, flexible, cost efficient synthesis method of anhydrous lanthanum halides and their solid solutions was developed. Several batches of ultrafine LaBr{sub 3}:Ce{sup +3} powder, free of oxyhalide, were produced by a rigorously …
Date: October 1, 2008
Creator: Boyle, Timothy J.; Ottley, Leigh Anna M.; Yang, Pin; Chen, Ching-Fong; Sanchez, Margaret R. & Bell, Nelson Simmons
Object Type: Report
System: The UNT Digital Library
Design and Implementation of an Open, Interoperable AutomatedDemand Response Infrastructure (open access)

Design and Implementation of an Open, Interoperable AutomatedDemand Response Infrastructure

This paper describes the concept for and lessons from the development and field-testing of an open, interoperable communications infrastructure to support automating demand response (DR). Automating DR allows greater levels of participation and improved reliability and repeatability of the demand response and customer facilities. Automated DR systems have been deployed for critical peak pricing and demand bidding and are being designed for real time pricing. The system is designed to generate, manage, and track DR signals between utilities and Independent System Operators (ISOs) to aggregators and end-use customers and their control systems.
Date: October 1, 2007
Creator: Piette, Mary Ann; Kiliccote, Sila & Ghatikar, Girish
Object Type: Article
System: The UNT Digital Library
Use Lower Flammable Limit Monitoring Equipment to Improve Process Oven Efficiency (open access)

Use Lower Flammable Limit Monitoring Equipment to Improve Process Oven Efficiency

This is one in a series of tip sheets to help manufacturers optimize their industrial process heating systems.
Date: October 1, 2007
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Dust mobilization and transport modeling for loss of vacuum accidents (open access)

Dust mobilization and transport modeling for loss of vacuum accidents

We develop a general continuum fluid dynamic model for dust transport in loss of vacuum accidents in fusion energy systems. The relationship between this general approach and established particle transport methods is clarified, in particular the relationship between the seemingly disparate treatments of aerosol dynamics and Lagrangian particle tracking. Constitutive equations for granular flow are found to be inadequate for prediction of mobilization, as these models essentially impose a condition of flow from the outset. Experiments confirm that at low shear, settled dust piles behave more like a continuum solid, and suitable solid models will be required to predict the onset of dust mobilization.
Date: October 1, 2007
Creator: Humrickhouse, P.W. & Sharpe, J.P.
Object Type: Article
System: The UNT Digital Library
Labs21 Laboratory Modeling Guidelines using ASHRAE 90.1-1999 (open access)

Labs21 Laboratory Modeling Guidelines using ASHRAE 90.1-1999

The following is a guideline for energy modeling of laboratory spaces in a building in accordance with the Energy Cost Budget method described in ASHRAE 90.1-1999 Energy Standard for Buildings Except Low-Rise Residential Buildings. For the purposes of this document, a laboratory is defined as any space requiring once through ventilation systems (recirculation of air to other spaces in a building is not allowed). To accomplish this, ventilation systems in laboratories typically provide 100% outside air to the occupied space. The guideline is structured similarly to the ASHRAE 90.1-99 standard. Only those sections being clarified or modified are discussed in the guideline; all other sections should be followed as defined in the standard. Specifically, those sections that are affected include the following: (1) 6.3.3.1 - Fan Power Limitation (modification); (2) 6.3.7.2 - Fume Hoods (modification); (3) 11.3.11 - Schedules (modification); (4) 11.4.3 - HVAC Systems (clarification); (5) 11.4.3 (h) Budget Supply-Air-to-Room Air Temperature Difference (modification); (6) 11.4.3(i) - Fan system efficiency (modification); and (7) Table 11.4.3A - Budget System Descriptions (modification). For energy efficiency measures that are not explicitly addressed by the standard, we recommend application of Section 11.5, Exceptional Calculation Methods. This guideline does not cover the details of …
Date: October 1, 2005
Creator: Reilly, Susan; Walsh, Michael; Graham, Carl; Maor, Itzhak; Mathew, Paul; Porter, Fred et al.
Object Type: Report
System: The UNT Digital Library
Solar Resource Assessment: Databases, Measurements, Models, and Information Sources (Fact Sheet) (open access)

Solar Resource Assessment: Databases, Measurements, Models, and Information Sources (Fact Sheet)

Fact sheet for Solar Resource Assessment Workshop, Denver CO, Oct 29, 2008: ?Solar Resource Assessment Databases, Measurements, Models, and Information Sources
Date: October 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Air, Thermal and Water Management for PEM Fuel Cell Systems (open access)

Air, Thermal and Water Management for PEM Fuel Cell Systems

This report has a detailed study of the fuel cells.
Date: October 1, 2008
Creator: Mirza, Mark K. Gee Zia
Object Type: Article
System: The UNT Digital Library
Economic Benefits, Carbon Dioxide (CO2) Emissions Reductions, and Water Conservation Benefits from 1,000 Megawatts (MW) of New Wind Power in Montana (Fact Sheet) (open access)

Economic Benefits, Carbon Dioxide (CO2) Emissions Reductions, and Water Conservation Benefits from 1,000 Megawatts (MW) of New Wind Power in Montana (Fact Sheet)

The U.S. Department of Energy?s Wind Powering America Program is committed to educating state-level policymakers and other stakeholders about the economic, CO2 emissions, and water conservation impacts of wind power. This analysis highlights the expected impacts of 1000 MW of wind power in Montana. Although construction and operation of 1000 MW of wind power is a significant effort, six states have already reached the 1000-MW mark. We forecast the cumulative economic benefits from 1000 MW of development in Montana to be $1.2 billion, annual CO2 reductions are estimated at 2.9 million tons, and annual water savings are 1,207 million gallons.
Date: October 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Search for Standard Model Higgs Bosons Produced in Association with W Bosons (open access)

Search for Standard Model Higgs Bosons Produced in Association with W Bosons

The authors report on the results of a search for standard model Higgs bosons produced in association with W bosons from p{bar p} collisions at {radical}s = 1.96 TeV. The search uses a data sample corresponding to approximately 1 fb{sup -1} of integrated luminosity. Events consistent with the W {yields} {ell}{nu} and H {yields} b{bar b} signature are selected by triggering on a high-p{sub T} electron or muon candidate and tagging one or two of the jet candidates as having originated from b quarks. A neural network filter rejects a fraction of tagged charm and light flavor jets, increasing the b-jet purity in the sample and thereby reducing the background to Higgs boson production. They observe no excess {ell}{nu}b{bar b} production beyond the background expectation, and they set 95% confidence level upper limits on the production cross section times branching fraction {sigma}(p{bar p} {yields} WH) {center_dot} Br(H {yields} b{bar b}) ranging from 3.9 to 1.3 pb, for specific Higgs boson mass hypotheses in the range 110 to 150 GeV/c{sup 2}, respectively.
Date: October 1, 2007
Creator: Aaltonen, T.
Object Type: Article
System: The UNT Digital Library
Fall Chinook Salmon Spawning Ground Surveys in the Snake River Basin Upriver of Lower Granite Dam, 2004 Annual Report. (open access)

Fall Chinook Salmon Spawning Ground Surveys in the Snake River Basin Upriver of Lower Granite Dam, 2004 Annual Report.

Redd counts were used to document the spawning distribution of fall Chinook salmon (Oncorhynchus tshawytscha) in the Snake River basin upriver of Lower Granite Dam. The first reported redd counts were from aerial searches conducted intermittently between 1959 and 1978 (Irving and Bjornn 1981, Witty 1988; Groves and Chandler 1996)(Appendix 1). In 1986, the Washington Department of Fish and Wildlife began an annual monitoring program that, in addition to the Snake River, included aerial searches of the Grande Ronde River the first year (Seidel and Bugert 1987), and the Imnaha River in subsequent years (Seidel et al. 1988; Bugert et al. 1989-1991; Mendel et al. 1992). The U.S. Fish and Wildlife Service and Idaho Power Company began contributing to this effort in 1991 by increasing the number of aerial searches conducted each year and adding underwater searches in areas of the Snake River that were too deep to be searched from the air (Connor et al. 1993; Garcia et al. 1994a, 1994b, 1996-2004; Groves 1993; Groves and Chandler 1996). The Nez Perce Tribe added aerial searches in the Clearwater River basin beginning in 1988 (Arnsberg et. al 1992), and the Salmon River beginning in 1992. Currently searches are conducted cooperatively …
Date: October 1, 2005
Creator: Garcia, A.P.; Bradbury, S.; Arnsberg, B.D.; Rocklage, S.J. & Groves, P.A.
Object Type: Report
System: The UNT Digital Library
A Concise Method for Storing and Communicating the Data Covariance Matrix (open access)

A Concise Method for Storing and Communicating the Data Covariance Matrix

The covariance matrix associated with experimental cross section or transmission data consists of several components. Statistical uncertainties on the measured quantity (counts) provide a diagonal contribution. Off-diagonal components arise from uncertainties on the parameters (such as normalization or background) that figure into the data reduction process; these are denoted systematic or common uncertainties, since they affect all data points. The full off-diagonal data covariance matrix (DCM) can be extremely large, since the size is the square of the number of data points. Fortunately, it is not necessary to explicitly calculate, store, or invert the DCM. Likewise, it is not necessary to explicitly calculate, store, or use the inverse of the DCM. Instead, it is more efficient to accomplish the same results using only the various component matrices that appear in the definition of the DCM. Those component matrices are either diagonal or small (the number of data points times the number of data-reduction parameters); hence, this implicit data covariance method requires far less array storage and far fewer computations while producing more accurate results.
Date: October 1, 2008
Creator: Larson, Nancy M
Object Type: Report
System: The UNT Digital Library
Vehicle Testing and Analysis Group: Center for Transportation Technologies and Systems (CTTS) (Brochure) (open access)

Vehicle Testing and Analysis Group: Center for Transportation Technologies and Systems (CTTS) (Brochure)

Describes NREL's Vehicle Testing and Analysis Group's work in vehicle and fleet evaluations, testing, data, and analysis for government and industry partners.
Date: October 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Molecular dynamics of membrane proteins. (open access)

Molecular dynamics of membrane proteins.

Understanding the dynamics of the membrane protein rhodopsin will have broad implications for other membrane proteins and cellular signaling processes. Rhodopsin (Rho) is a light activated G-protein coupled receptor (GPCR). When activated by ligands, GPCRs bind and activate G-proteins residing within the cell and begin a signaling cascade that results in the cell's response to external stimuli. More than 50% of all current drugs are targeted toward G-proteins. Rho is the prototypical member of the class A GPCR superfamily. Understanding the activation of Rho and its interaction with its Gprotein can therefore lead to a wider understanding of the mechanisms of GPCR activation and G-protein activation. Understanding the dark to light transition of Rho is fully analogous to the general ligand binding and activation problem for GPCRs. This transition is dependent on the lipid environment. The effect of lipids on membrane protein activity in general has had little attention, but evidence is beginning to show a significant role for lipids in membrane protein activity. Using the LAMMPS program and simulation methods benchmarked under the IBIG program, we perform a variety of allatom molecular dynamics simulations of membrane proteins.
Date: October 1, 2004
Creator: Woolf, Thomas B. (Johns Hopkins University School of Medicine, Baltimore, MD); Crozier, Paul Stewart & Stevens, Mark Jackson
Object Type: Report
System: The UNT Digital Library