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FreedomCAR :electrical energy storage system abuse test manual for electric and hybrid electric vehicle applications

Doughty, Daniel H.

This manual defines a complete body of abuse tests intended to simulate actual use and abuse conditions that may be beyond the normal safe operating limits experienced by electrical energy storage systems used in electric and hybrid electric vehicles. The tests are designed to provide a common framework for abuse testing various electrical energy storage systems used in both electric and hybrid electric vehicle applications. The manual incorporates improvements and refinements to test descriptions presented in the Society of Automotive Engineers Recommended Practice SAE J2464 ''Electric Vehicle Battery Abuse Testing'' including adaptations to abuse tests to address hybrid electric vehicle applications and other energy storage technologies (i.e., capacitors). These (possibly destructive) tests may be used as needed to determine the response of a given electrical energy storage system design under specifically defined abuse conditions. This manual does not provide acceptance criteria as a result of the testing, but rather provides results that are accurate and fair and, consequently, comparable to results from abuse tests on other similar systems. The tests described are intended for abuse testing any electrical energy storage system designed for use in electric or hybrid electric vehicle applications whether it is composed of batteries, capacitors, or a combination of the two.

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Heavy ion beam induced current/charge (IBIC) through insulating oxides

Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms

Vizkelethy, Gyorgy; Brice, David K.; Doyle, B.L.

Model experiments were performed on MOS (metal-oxide semiconductor) capacitors to study ion beam induced charge generation in silicon-on-insulator (SOI) devices. Surprisingly large induced charge was found and a lateral non-uniformity of the induced charge was discovered across the top electrode of the capacitor. In this paper we will give a simple model for the charge induction in MOS structures and an explanation of the lateral changes in the amount of induced charge. © 2006 Elsevier B.V. All rights reserved.

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PIXE-quantified AXSIA: Elemental mapping by multivariate spectral analysis

Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms

Doyle, B.L.; Provencio, P.N.; Kotula, Paul G.; Antolak, Arlyn J.; Ryan, C.G.; Campbell, J.L.; Barrett, K.

Automated, nonbiased, multivariate statistical analysis techniques are useful for converting very large amounts of data into a smaller, more manageable number of chemical components (spectra and images) that are needed to describe the measurement. We report the first use of the multivariate spectral analysis program AXSIA (Automated eXpert Spectral Image Analysis) developed at Sandia National Laboratories to quantitatively analyze micro-PIXE data maps. AXSIA implements a multivariate curve resolution technique that reduces the spectral image data sets into a limited number of physically realizable and easily interpretable components (including both spectra and images). We show that the principal component spectra can be further analyzed using conventional PIXE programs to convert the weighting images into quantitative concentration maps. A common elemental data set has been analyzed using three different PIXE analysis codes and the results compared to the cases when each of these codes is used to separately analyze the associated AXSIA principal component spectral data. We find that these comparisons are in good quantitative agreement with each other. © 2006 Elsevier B.V. All rights reserved.

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Size exclusion chromatography of microliter volumes for on-line use in low-pressure microfluidic systems

Analytical Chemistry

Chirica, Gabriela; Lachmann, J.; Chan, J.

We have developed a new cartridge format for on-line size exclusion processing in low-pressure, portable microfluidic devices. The described system allows size exclusion chromatography of microliter volumes (termed μL-SEC) to be performed with ready integration in complex protocols for continuous-flow sample processing and analysis. The refillable cartridge format was employed for the preparation of Bacillus subtilus spores lysed in the presence of a strong reducing agent. While the reducing agent is known to interfere with subsequent fluorescent labeling of the solubilized proteins, the described continuous-flow size exclusion processing allowed complete isolation of interferences from a 10-μL sample in 70 s. Following efficient labeling, the protein sample was injected and separated on-chip using gel electrophoresis. To increase the resolution, speed, and sample capacity of buffer exchange under low-pressure operation (40 psi), parameters such as the size exclusion resin, load volumes, flow rates, buffer composition, and cartridge geometry were optimized and are presented here. The μL-SEC analysis is compatible with automated sample preparation for microfluidic systems and has resulted in significantly increased analysis speed and throughput over benchtop methods. The presented technique has the potential to improve capabilities such as buffer exchange, size fractionation, and high-abundance protein removal-steps that are frequently required prior to on-chip, point-of-care, and mass spectrometric analyses. © 2006 American Chemical Society.

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A critical implanted Cl concentration for pit initiation on aluminum thin films

Journal of the Electrochemical Society

Serna, L.M.; Zavadil, Kevin R.; Johnson, C.M.; Wall, Frederick D.; Barbour, J.C.

The pitting potential of pure aluminum thin films in 50 mM K2 S O4 was measured as a function of implanted Cl fluence. Samples were implanted with 35 keV Cl+ at room temperature using fluences from 2.25× 1016 to 3.25× 1016 ions cm-2 in increments of 0.25× 1016. An empirical relationship between pitting potential and fluence was found which suggests a critical Cl concentration in the oxide is necessary for pit initiation. No correlation between pitting potential and the measured Cl concentration or distribution in the metal was found. © 2006 The Electrochemical Society. All rights reserved.

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Critical manifolds in non-linear response of complex materials

Mechanics of Materials

Duxbury, P.M.; McGarrity, E.S.; Holm, Elizabeth A.

We describe two geometric structures, the shortest path and the minimum cut, and show that these structures emerge at special threshold points in the highly non-linear electrical response of complex networks. Algorithms which find the shortest path and the minimum cut directly as well as methods for finding the full non-linear response of complex networks are outlined. Scaling laws for the behavior of the shortest path and minimum cut in random networks are then surveyed. Finally, applications of the shortest path and minimum cut to grain boundary controlled polycrystalline materials are elucidated. © 2005 Elsevier Ltd. All rights reserved.

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Experimental results of single screw mechanical tests: a follow-up to SAND2005-6036

Mcfadden, Sam X.; Lee, Kenneth L.; Korellis, John S.; Lee, Sandwook

The work reported here was conducted to address issues raised regarding mechanical testing of attachment screws described in SAND2005-6036, as well as to increase the understanding of screw behavior through additional testing. Efforts were made to evaluate fixture modifications and address issues of interest, including: fabrication of 45{sup o} test fixtures, measurement of the frictional load from the angled fixture guide, employment of electromechanical displacement transducers, development of a single-shear test, and study the affect of thread start orientation on single-shear behavior. A286 and 302HQ, No.10-32 socket-head cap screws were tested having orientations with respect to the primary loading axis of 0{sup 0}, 45{sup o}, 60{sup o}, 75{sup o} and 90{sup o} at stroke speeds 0,001 and 10 in/sec. The frictional load resulting from the angled screw fixture guide was insignificant. Load-displacement curves of A286 screws did not show a minimum value in displacement to failure (DTF) for 60{sup o} shear tests. Tests of 302HQ screws did not produce a consistent trend in DTF with load angle. The effect of displacement rate on DTF became larger as shear angle increased for both A286 and 302HQ screws.

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An evaluation of the spring finger solder joints on SA1358-10 and SA2052-4 connector assemblies (MC3617,W87)

Vianco, Paul T.; Kilgo, Alice C.; Zender, Gary L.; Hlava, Paul F.

The SA1358-10 and SA2052-4 circular JT Type plug connectors are used on a number of nuclear weapons and Joint Test Assembly (JTA) systems. Prototype units were evaluated for the following specific defects associated with the 95Sn-5Sb (Sn-Sb, wt.%) solder joint used to attach the beryllium-copper (BeCu) spring fingers to the aluminum (Al) connector shell: (1) extended cracking within the fillet; (2) remelting of the solder joint during the follow-on, soldering step that attached the EMR adapter ring to the connector shell (and/or soldering the EMR shell to the adapter ring) that used the lower melting temperature 63Sn-37Pb (Sn-Pb) alloy; and (3) spalling of the Cd (Cr) layer overplating layer from the fillet surface. Several pedigrees of connectors were evaluated, which represented older fielded units as well as those assemblies that were recently constructed at Kansas City Plant. The solder joints were evaluated that were in place on connectors made with the current soldering process as well as an alternative induction soldering process for attaching the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely reflected the different extents to which the connector was mated to its counterpart assembly. In all cases, the spring finger solder joints on the SA1358-10 connectors were remelted as a result of the subsequent EMR adapter ring attachment process. Spalling of the Cd (Cr) overplating layer was also observed for these connectors, which was a consequence of the remelting activity. On the other hand, the SA2052-4 connector did not exhibit evidence of remelting of the spring finger solder joint. The Cd (Cr) layer did not show signs of spalling. These results suggested that, due to the size of the SA1358-10 connector, any of the former or current soldering processes used to attach the EMR adapter ring and/or EMR shell to the connector shell, requires a level of heat energy that will always result in the remelting of the spring finger solder joint attached with either the Sn-Ag or the Sn-Sb alloy. Lastly, it was construed that the induction soldering process, which is used to attach the EMR adapter ring onto the shell, was more likely to have caused the remelting event rather than the more localized heat source of the hand soldering iron used to attach the EMR shell to the adapter ring.

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On the formulation of a crystal plasticity model

Marin, Esteban B.

This report presents the formulation of a crystal elasto-viscoplastic model and the corresponding integration scheme. The model is suitable to represent the isothermal, anisotropic, large deformation of polycrystalline metals. The formulation is an extension of a rigid viscoplastic model to account for elasticity effects, and incorporates a number of changes with respect to a previous formulation [Marin & Dawson, 1998]. This extension is formally derived using the well-known multiplicative decomposition of the deformation gradient into an elastic and plastic components, where the elastic part is additionally decomposed into the elastic stretch V{sup e} and the proper orthogonal R{sup e} tensors. The constitutive equations are written in the intermediate, stress-free configuration obtained by unloading the deformed crystal through the elastic stretch V{sup e-}. The model is framed in a thermodynamic setting, and developed initially for large elastic strains. The crystal equations are then specialized to the case of small elastic strains, an assumption typically valid for metals. The developed integration scheme is implicit and proceeds by separating the spherical and deviatoric crystal responses. An ''approximate'' algorithmic material moduli is also derived for applications in implicit numerical codes. The model equations and their integration procedure have been implemented in both a material point simulator and a commercial finite element code. Both implementations are validated by solving a number of examples involving aggregates of either face centered cubic (FCC) or hexagonal close-packed (HCP) crystals subjected to different loading paths.

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Improved InGaN epitaxy yield by precise temperature measurement :yearly report 1

Creighton, James R.; Koleske, Daniel; Russell, Michael J.; Fischer, Arthur J.

This Report summarizes the first year progress (October 1, 2004 to September 30, 2005) made under a NETL funded project entitled ''Improved InGaN Epitaxy Yield by Precise Temperature Measurement''. This Project addresses the production of efficient green LEDs, which are currently the least efficient of the primary colors. The Project Goals are to advance IR and UV-violet pyrometry to include real time corrections for surface emissivity on multiwafer MOCVD reactors. Increasing wafer yield would dramatically reduce high brightness LED costs and accelerate the commercial manufacture of inexpensive white light LEDs with very high color quality. This work draws upon and extends our previous research (funded by DOE) that developed emissivity correcting pyrometers (ECP) based on the high-temperature GaN opacity near 400 nm (the ultraviolet-violet range, or UVV), and the sapphire opacity in the mid-IR (MIR) near 7.5 microns.

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Solid-state lighting technology perspective

Coltrin, Michael E.; Tsao, Jeffrey Y.

Solid-State Lighting (SSL) uses inorganic light-emitting diodes (LEDs) and organic light-emitting diodes (OLEDs) to convert electricity into light for illumination. SSL has the potential for enormous energy savings and accompanying environmental benefits if its promise of 50% (or greater) energy efficiencies can be achieved. This report provides a broad summary of the technologies that underlie SSL. The applications for SSL and potential impact on U.S. and world-wide energy consumption, and impact on the human visual experience are discussed. The properties of visible light and different technical metrics to characterize its properties are summarized. The many factors contributing to the capital and operating costs for SSL and traditional lighting sources (incandescent, fluorescent, and high-intensity discharge lamps) are discussed, with extrapolations for future SSL goals. The technologies underlying LEDs and OLEDs are also described, including current and possible alternative future technologies and some of the present limitations.

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Characterization of Aluminum Honeycomb and Experimentation for Model Development and Validation, Volume I: Discovery and Characterization Experiments for High-Density Aluminum Honeycomb

Lu, Wei-Yang; Korellis, John S.; Lee, Kenneth L.; Scheffel, Simon; Hinnerichs, Terry D.; Neilsen, Michael K.; Scherzinger, William M.

Honeycomb is a structure that consists of two-dimensional regular arrays of open cells. High-density aluminum honeycomb has been used in weapon assemblies to mitigate shock and protect payload because of its excellent crush properties. In order to use honeycomb efficiently and to certify the payload is protected by the honeycomb under various loading conditions, a validated honeycomb crush model is required and the mechanical properties of the honeycombs need to be fully characterized. Volume I of this report documents an experimental study of the crush behavior of high-density honeycombs. Two sets of honeycombs were included in this investigation: commercial grade for initial exploratory experiments, and weapon grade, which satisfied B61 specifications. This investigation also includes developing proper experimental methods for crush characterization, conducting discovery experiments to explore crush behaviors for model improvement, and identifying experimental and material uncertainties.

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Asynchronous parallel generating set search for linearly-constrained optimization

Griffin, Joshua D.

Generating set search (GSS) is a family of direct search methods that encompasses generalized pattern search and related methods. We describe an algorithm for asynchronous linearly-constrained GSS, which has some complexities that make it different from both the asynchronous bound-constrained case as well as the synchronous linearly-constrained case. The algorithm has been implemented in the APPSPACK software framework and we present results from an extensive numerical study using CUTEr test problems. We discuss the results, both positive and negative, and conclude that GSS is a reliable method for solving small-to-medium sized linearly-constrained optimization problems without derivatives.

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Multiple predictor smoothing methods for sensitivity analysis

Helton, Jon C.; Storlie, Curtis B.

The use of multiple predictor smoothing methods in sampling-based sensitivity analyses of complex models is investigated. Specifically, sensitivity analysis procedures based on smoothing methods employing the stepwise application of the following nonparametric regression techniques are described: (1) locally weighted regression (LOESS), (2) additive models, (3) projection pursuit regression, and (4) recursive partitioning regression. The indicated procedures are illustrated with both simple test problems and results from a performance assessment for a radioactive waste disposal facility (i.e., the Waste Isolation Pilot Plant). As shown by the example illustrations, the use of smoothing procedures based on nonparametric regression techniques can yield more informative sensitivity analysis results than can be obtained with more traditional sensitivity analysis procedures based on linear regression, rank regression or quadratic regression when nonlinear relationships between model inputs and model predictions are present.

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Impact of polymer film thickness and cavity size on polymer flow during embossing : towards process design rules for nanoimprint lithography

Schunk, Peter R.

This paper presents continuum simulations of polymer flow during nanoimprint lithography (NIL). The simulations capture the underlying physics of polymer flow from the nanometer to millimeter length scale and examine geometry and thermophysical process quantities affecting cavity filling. Variations in embossing tool geometry and polymer film thickness during viscous flow distinguish different flow driving mechanisms. Three parameters can predict polymer deformation mode: cavity width to polymer thickness ratio, polymer supply ratio, and Capillary number. The ratio of cavity width to initial polymer film thickness determines vertically or laterally dominant deformation. The ratio of indenter width to residual film thickness measures polymer supply beneath the indenter which determines Stokes or squeeze flow. The local geometry ratios can predict a fill time based on laminar flow between plates, Stokes flow, or squeeze flow. Characteristic NIL capillary number based on geometry-dependent fill time distinguishes between capillary or viscous driven flows. The three parameters predict filling modes observed in published studies of NIL deformation over nanometer to millimeter length scales. The work seeks to establish process design rules for NIL and to provide tools for the rational design of NIL master templates, resist polymers, and process parameters.

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Circulating fluidized bed hydrodynamics experiments for the multiphase fluid dynamics research consortium (MFDRC)

Trujillo, Steven M.; Torczynski, John R.; Tortora, Paul R.; O'Hern, Timothy J.

An experimental program was conducted to study the multiphase gas-solid flow in a pilot-scale circulating fluidized bed (CFB). This report describes the CFB experimental facility assembled for this program, the diagnostics developed and/or applied to make measurements in the riser section of the CFB, and the data acquired for several different flow conditions. Primary data acquired included pressures around the flow loop and solids loadings at selected locations in the riser. Tomographic techniques using gamma radiation and electrical capacitance were used to determine radial profiles of solids volume fraction in the riser, and axial profiles of the integrated solids volume fraction were produced. Computer Aided Radioactive Particle Tracking was used to measure solids velocities, fluxes, and residence time distributions. In addition, a series of computational fluid dynamics simulations was performed using the commercial code Arenaflow{trademark}.

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A novel electron gun with an independently addressable cathode array

Schneider, Larry X.; Pena, Gary; Rudys, Joseph M.

The design of a novel electron gun with an array of independently addressable cathode elements is presented. Issues relating to operation in a 6.5 Tesla axial magnetic field are discussed. Simulations with the TriComp electromagnetic field code that were used to determine the space charge limited tube characteristic and to model focusing of the electron beam in the magnetic field are reviewed. Foil heating and stress calculations are discussed. The results of CYLTRAN simulations yielding the energy spectrum of the electron beam and the current transmitted through the foil window are presented.

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QCS : a system for querying, clustering, and summarizing documents

Dunlavy, Daniel M.

Information retrieval systems consist of many complicated components. Research and development of such systems is often hampered by the difficulty in evaluating how each particular component would behave across multiple systems. We present a novel hybrid information retrieval system--the Query, Cluster, Summarize (QCS) system--which is portable, modular, and permits experimentation with different instantiations of each of the constituent text analysis components. Most importantly, the combination of the three types of components in the QCS design improves retrievals by providing users more focused information organized by topic. We demonstrate the improved performance by a series of experiments using standard test sets from the Document Understanding Conferences (DUC) along with the best known automatic metric for summarization system evaluation, ROUGE. Although the DUC data and evaluations were originally designed to test multidocument summarization, we developed a framework to extend it to the task of evaluation for each of the three components: query, clustering, and summarization. Under this framework, we then demonstrate that the QCS system (end-to-end) achieves performance as good as or better than the best summarization engines. Given a query, QCS retrieves relevant documents, separates the retrieved documents into topic clusters, and creates a single summary for each cluster. In the current implementation, Latent Semantic Indexing is used for retrieval, generalized spherical k-means is used for the document clustering, and a method coupling sentence ''trimming'', and a hidden Markov model, followed by a pivoted QR decomposition, is used to create a single extract summary for each cluster. The user interface is designed to provide access to detailed information in a compact and useful format. Our system demonstrates the feasibility of assembling an effective IR system from existing software libraries, the usefulness of the modularity of the design, and the value of this particular combination of modules.

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Surface-wave and refraction tomography at the FACT Site, Sandia National Laboratories, Albuquerque, New Mexico

Bartel, Lewis C.; Engler, Bruce P.

We present a technique that allows for the simultaneous acquisition and interpretation of both shear-wave and compressive-wave 3-D velocities. The technique requires no special seismic sources or array geometries, and is suited to studies with small source-receiver offsets. The method also effectively deals with unwanted seismic arrivals by using the statistical properties of the data itself to discriminate against spurious picks. We demonstrate the technique with a field experiment at the Facility for Analysis, Calibration, and Testing at Sandia National Laboratories, Albuquerque, New Mexico. The resulting 3-D shear-velocity and compressive-velocity distributions are consistent with surface geologic mapping. The averaged velocities and V{sub p}/V{sub s} ratio in the upper 30 meters are also consistent with examples found in the scientific literature.

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Laboratory measurement verification of laser hazard analysis for miles weapon simulators used in force on force exercises

Augustoni, Arnold L.

Due to the change in the batteries used with the Small Arm Laser Transmitters (SALT) from 3-volts dc to 3.6-volts dc and changes to SNL MILES operating conditions, the associated laser hazards of these units required re-evaluation to ensure that the hazard classification of the laser emitters had not changed as well. The output laser emissions of the SNL MILES, weapon simulators and empire guns, used in Force-On-Force (FOF) training exercises, was measured in accordance to the ANSI Standard Z136.4-2005, ''Recommended Practice for Laser Safety Measurements for Hazard Evaluation''. The laser hazard class was evaluated in accordance with the ANSI Standard Z136.1-2000, ''Safe Use of Lasers'', using ''worst'' case conditions associated with these MILES units. Laser safety assessment was conducted in accordance with the ANSI Standard Z136.6-2005, ''Safe Use of Lasers Outdoors''. The laser hazard evaluation of these MILES laser emitters was compared to and supersedes SAND Report SAND2002-0246, ''Laser Safety Evaluation of the MILES and Mini MILES Laser Emitting Components'', which used ''actual'' operating conditions of the laser emitters at the time of its issuance.

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Results 83801–83900 of 99,299
Results 83801–83900 of 99,299