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Hybrid options for light-duty vehicles.

Description: Hybrid electric vehicles (HEVs) offer great promise in improving fuel economy. In this paper, we analyze why, how, and by how much vehicle hybridization can reduce energy consumption and improve fuel economy. Our analysis focuses on efficiency gains associated solely with vehicle hybridization. We do not consider such other measures as vehicle weight reduction or air- and tire-resistance reduction, because such measures would also benefit conventional technology vehicles. The analysis starts with understanding the energy inefficiencies of light-duty vehicles associated with different operation modes in US and Japanese urban and highway driving cycles, with the corresponding energy-saving potentials. The potential for fuel economy gains due to vehicle hybridization can be estimated almost exclusively on the basis of three elements: the reducibility of engine idling operation, the recoverability of braking energy losses, and the capability of improving engine load profiles to gain efficiency associated with specific HEV configurations and control strategies. Specifically, we evaluate the energy efficiencies and fuel economies of a baseline MY97 Corolla-like conventional vehicle (CV), a hypothetical Corolla-based minimal hybrid vehicle (MHV), and a MY98 Prius-like full hybrid vehicle (FHV). We then estimate energy benefits of both MHVs and FHVs over CVs on a performance-equivalent basis. We conclude that the energy benefits of hybridization vary not only with test cycles, but also with performance requirements. The hybrid benefits are greater for ''Corolla (high) performance-equivalent'' vehicles than for ''Prius (low) performance-equivalent'' vehicles. An increasing acceleration requirement would result in larger fuel economy benefits from vehicle hybridization.
Date: July 19, 1999
Creator: An, F., Stodolsky, F. & Santini, D.
Partner: UNT Libraries Government Documents Department

Development of practical damage-mapping and inspection systems

Description: We have developed and are continuing to refine semi-automated technology for the detection and inspection of surface and bulk defects and damage in large laser optics Different manifestations of the DAMOCLES system (Damage and Artifact Mapping Of Coherent-Laser-Exposed Substrates) provide an effective and economical means of being able to detect, map and characterize surface and bulk defects which may become precursors of massive damage in optics when subjected to high-fluence laser irradiation Subsequent morphology and evolution of damage due to laser irradiation can be tracked efficiently The strength of the Damocles system is that it allows for immediate visual observation of defects in an entire optic, which can range up to l-meter dimensions, while also being able to provide digital map and magnified images of the defects with resolutions better than 5 ┬Ám.
Date: August 19, 1998
Creator: Rainer, F.
Partner: UNT Libraries Government Documents Department

Thermal management concepts for higher efficiency heavy vehicles.

Description: Thermal management is a cross-cutting technology that directly or indirectly affects engine performance, fuel economy, safety and reliability, aerodynamics, driver/passenger comfort, materials selection, emissions, maintenance, and component life. This review paper provides an assessment of thermal management for large trucks, particularly as it impacts these features. Observations arrived at from a review of the state of the art for thermal management for over-the-road trucks are highlighted and commented on. Trends in the large truck industry, pertinent engine truck design and performance objectives, and the implications of these relative to thermal management, are presented. Finally, new thermal management concepts for high efficiency vehicles are described.
Date: May 19, 1999
Creator: Wambsganss, M. W.
Partner: UNT Libraries Government Documents Department

Calibration of an Advanced Photon Source linac beam position monitor used for positron position measurement of a beam containing both positrons and electrons.

Description: The Advanced Photon Source (APS) linac beam position monitors can be used to monitor the position of a positron beam also containing electrons. To accomplish this task, both the signal at the bunching frequency of 2856 MHz and the signal at 2 x 2856 MHz are acquired and processed for each stripline. The positron beam position is obtained by forming a linear combination of both 2856- and 5712-MHz signals for each stripline and then performing the standard difference over sum computation. The required linear combination of the 2856- and 5712-MHz signals depends on the electrical calibration of each stripline/cable combination. In this paper, the calibration constants for both 2856-MHz and 5712-MHz signals for each stripline are determined using a pure beam of electrons. The calibration constants are obtained by measuring the 2856- and 5712-MHz stripline signals at various electron beam currents and positions. Finally, the calibration constants measured using electrons are used to determine positron beam position for the mixed beam case.
Date: May 19, 1998
Creator: Sereno, N. S.
Partner: UNT Libraries Government Documents Department

Sol gel based fiber optic sensor for blook pH measurement

Description: This paper describes a fiber-optic pH sensor based upon sol-gel encapsulation of a self-referencing dye, seminaphthorhodamine-1 carboxylate (SNARF-1C). The simple sol-gel fabrication procedure and low coating leachability are ideal for encapsulation and immobilization of dye molecules onto the end of an optical fiber. A miniature bench-top fluorimeter system was developed for use with the optical fiber to obtain pH measurements. Linear and reproducible responses were obtained in human blood in the pH range 6.8 to 8.0, which encompasses the clinically-relevant range. Therefore, this sensor can be considered for in vivo use.
Date: December 19, 1996
Creator: Grant, S. A. & Glass, R. S.
Partner: UNT Libraries Government Documents Department

The RERTR Program : a status report.

Description: This paper describes the progress achieved by the Reduced Enrichment for Research and Test Reactors (RERTR) Program in collaboration with its many international partners since its inception in 1978. A brief summary of the results that the program had attained by the end of 1997 is followed by a detailed review of the major events, findings, and activities that took place in 1998. The past year was characterized by exceptionally important accomplishments and events for the RERTR program. Four additional shipments of spent fuel from foreign research reactors were accepted by the U.S. Altogether, 2,231 spent fuel assemblies from foreign research reactors have been received by the U.S. under the acceptance policy. Fuel development activities began to yield solid results. Irradiations of the first two batches of microplates were completed. Preliminary postirradiation examinations of these microplates indicate excellent irradiation behavior of some of the fuel materials that were tested. These materials hold the promise of achieving the pro am goal of developing LEU research reactor fuels with uranium density in the 8-9 g /cm{sup 3} range. Progress was made in the Russian RERTR program, which aims to develop and demonstrate the technical means needed to convert Russian-supplied research reactors to LEU fuels. Feasibility studies for converting to LEU fuel four Russian-designed research reactors (IR-8 in Russia, Budapest research reactor in Hungary, MARIA in Poland, and WWR-SM in Uzbekistan) were completed. A new program activity began to study the feasibility of converting three Russian plutonium production reactors to the use of low-enriched U0{sub 2}-Al dispersion fuel, so that they can continue to produce heat and electricity without producing significant amounts of plutonium. The study of an alternative LEU core for the FRM-II design has been extended to address, with favorable results, the transient performance of the core under hypothetical accident conditions. ...
Date: October 19, 1998
Creator: Travelli, A.
Partner: UNT Libraries Government Documents Department

Glass material oxidation and dissolution system: Converting miscellaneous fissile materials to glass

Description: The cold war and the development of nuclear energy have resulted in significant inventories of miscellaneous fissile materials (MFMs). MFMs include (1) plutonium scrap and residue, (2) miscellaneous spent nuclear fuel (SNF), (3) certain hot cell wastes, and (4) many one-of-a-kind materials. Major concerns associated with the long-term management of these materials include: safeguards and nonproliferation issues; health, environment, and safety concerns. waste management requirements; and high storage costs. These issues can be addressed by converting the MFMs to glass for secure, long-term storage or repository disposal; however, conventional glass-making processes require oxide-like feed materials. Converting MFMs to oxide-like materials with subsequent vitrification is a complex and expensive process. A new vitrification process has been invented, the Glass Material Oxidation and Dissolution System (GMODS), which directly converts metals, ceramics, and amorphous solids to glass; oxidizes organics with the residue converted to glass; and converts chlorides to borosilicate glass and a secondary sodium chloride (NaCl) stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium, Zircaloy, stainless steel, multiple oxides, and other materials to glass. However, significant work is required to develop GMODS further for applications at an industrial scale. If implemented, GMODS will provide a new approach to manage these materials.
Date: March 19, 1996
Creator: Forsberg, C.W. & Ferrada, J.J.
Partner: UNT Libraries Government Documents Department

Signals from flavor changing scalar neutral currents at {mu}{sup +}{mu}{sup {minus}} colliders

Description: We illustrate the possibility of observing signals from Flavor Changing Neutral Currents, originating from the scalar sector of a Two Higgs Doublet Model. In particular, we focus on the tree level process {mu}{sup +}{mu}{sup {minus}} {yields} {bar t}c + {bar c}t, via scalar exchange in the s-channel, as a distinctive process for {mu}{sup +}{mu}{sup {minus}} colliders. 12 refs., 1 fig.
Date: January 19, 1996
Creator: Reina, L.
Partner: UNT Libraries Government Documents Department

Impact of detailed radiation transport on volume recombination

Description: Recently both the Alcator C-Mod and DIII-D tokamaks observed significant recombination of major ion species in the divertor region during detachment. For sufficiently low temperatures the mixture of neutral atoms and ions can be optically thick to line radiation. The optical depth of the recombined region to Ly{alpha} radiation can be very large and opacity effects and radiation trapping can dramatically change the heat flux to the divertor walls. This paper presents an analysis of the effect of line radiation on volume recombination using CRETIN, a multi-dimensional, non-local thermodynamic equilibrium simulation code that includes the atomic kinetics and radiative transport processes necessary to model this complex environment.
Date: May 19, 1998
Creator: Scott, H., LLNL
Partner: UNT Libraries Government Documents Department

Confidence Calculation with AMV+

Description: The iterative advanced mean value algorithm (AMV+), introduced nearly ten years ago, is now widely used as a cost-effective probabilistic structural analysis tool when the use of sampling methods is cost prohibitive (Wu et al., 1990). The need to establish confidence bounds on calculated probabilities arises because of the presence of uncertainties in measured means and variances of input random variables. In this paper an algorithm is proposed that makes use of the AMV+ procedure and analytically derived probability sensitivities to determine confidence bounds on calculated probabilities.
Date: February 19, 1999
Creator: Fossum, A.F.
Partner: UNT Libraries Government Documents Department

Application of environmental accounting to pollution prevention

Description: Environmental accounting represents a major paradigm shift in the way most companies account for costs and benefits. However, it is a change that must be made if pollution prevention is to become institutionalized into the corporate and government mainstream. Pollution prevention investments must be justified on an economic basis; without environmental accounting tools, pollution prevention investments cannot show their true profitability. This is because traditional accounting methods only track billable costs, thus ignoring some of the major benefits of pollution prevention investments, which are indirect savings resulting from a lessening of a company`s regulatory compliance burden and present and future liabilities. This paper discusses how to apply environmental accounting principles to pollution prevention assessments to improve the outcome of profitability analyses.
Date: August 19, 1997
Creator: Del Mar, R.A.
Partner: UNT Libraries Government Documents Department

Radcalc for windows benchmark study: A comparison of software results with Rocky Flats hydrogen gas generation data

Description: Radcalc for Windows Version 2.01 is a user-friendly software program developed by Waste Management Federal Services, Inc., Northwest Operations for the U.S. Department of Energy (McFadden et al. 1998). It is used for transportation and packaging applications in the shipment of radioactive waste materials. Among its applications are the classification of waste per the US. Department of Transportation regulations, the calculation of decay heat and daughter products, and the calculation of the radiolytic production of hydrogen gas. The Radcalc program has been extensively tested and validated (Green et al. 1995, McFadden et al. 1998) by comparison of each Radcalc algorithm to hand calculations. An opportunity to benchmark Radcalc hydrogen gas generation calculations to experimental data arose when the Rocky Flats Environmental Technology Site (RFETS) Residue Stabilization Program collected hydrogen gas generation data to determine compliance with requirements for shipment of waste in the TRUPACT-II (Schierloh 1998). The residue/waste drums tested at RFETS contain contaminated, solid, inorganic materials in polyethylene bags. The contamination is predominantly due to plutonium and americium isotopes. The information provided by Schierloh (1 998) of RFETS includes decay heat, hydrogen gas generation rates, calculated G{sub eff} values, and waste material type, making the experimental data ideal for benchmarking Radcalc. The following sections discuss the RFETS data and the Radcalc cases modeled with the data. Results are tabulated and also provided graphically.
Date: July 19, 1999
Creator: MCFADDEN, J.G.
Partner: UNT Libraries Government Documents Department

Modeling of the Savannah River Site High Level Waste Evaporator Systems

Description: Three evaporators are used to reduce the volume of waste in the waste tank farm at the Savannah River Site (SRS). Evaporators are crucial operation in the SRS waste processing and management system. Using the Aspen Custom Modeler(TM) (ACM) software package marketed by Aspen Technology, Inc., the evaporator dynamic flowsheet models have been constructed to simulate the behavior of the evaporator systems. The evaporator models are used to assist operations and planning. The models account for the basic arrangement and flowpath for the evaporators: (1) Feed system, (2) Concentrate system, (3) Overheads system, and (4) Steam system. This paper provides a detailed description of the model development and presents the result of a typical simulation scenario.
Date: February 19, 2003
Creator: Hang, T.
Partner: UNT Libraries Government Documents Department

QCD Results from the CDF Experiment at squareroot s = 1.96 TeV

Description: First QCD results obtained from the CDF experiment using Run II data are reported. The Run II physics program at the Tevatron started in the spring of 2001, with protons and anti-protons colliding at an energy of {radical}s = 1.96 TeV. The size of the data sample already compares to that of Run I. Results presented here include the measurement of the inclusive jet cross section, a search for new particles decaying to dijets, and a study of diffractive dijet events.
Date: May 19, 2003
Creator: Gallinaro, Michele
Partner: UNT Libraries Government Documents Department

Supernovae and neutrinos

Description: A long-standing problem in supernova physics is how to measure the total energy and temperature of {nu}{sub {mu}}, {nu}{sub {tau}}, {bar {nu}}{sub {mu}}, and {bar {nu}}{sub {tau}}. While of the highest importance, this is very difficult because these flavors only have neutral-current detector interactions. We propose that neutrino-proton elastic scattering, {nu} + p {yields} {nu} + p, can be used for the detection of supernova neutrinos in scintillator detectors. It should be emphasized immediately that the dominant signal is on free protons. Though the proton recoil kinetic energy spectrum is soft, with T{sub p} {approx_equal} 2E{sub {nu}}{sup 2}/M{sub p}, and the scintillation light output from slow, heavily ionizing protons is quenched, the yield above a realistic threshold is nearly as large as that from {bar {nu}}{sub e} + p {yields} e{sup +} + n. In addition, the measured proton spectrum is related to the incident neutrino spectrum. The ability to detect this signal would give detectors like KamLAND and Borexino a crucial and unique role in the quest to detect supernova neutrinos.
Date: September 19, 2002
Creator: Beacom, John F.
Partner: UNT Libraries Government Documents Department

Status of Neutrino Factory R&D within the Muon Collaboration

Description: The authors describe the current status of the research within the Muon Collaboration towards realizing a Neutrino Factory. The authors describe briefly the physics motivation behind the neutrino factory approach to studying neutrino oscillations and the longer term goal of building the Muon Collider. The benefits of a step by step staged approach of building a proton driver, collecting and cooling muons followed by the acceleration and storage of cooled muons are emphasized. Several usages of cooled muons open up at each new stage in such an approach and new physics opportunities are realized at the completion of each stage.
Date: February 19, 2004
Creator: Raja, Rajendran
Partner: UNT Libraries Government Documents Department

Report of the subgroup on alternative models and new ideas

Description: We summarize some of the work done by the P3 subgroup on Alternative Models and New Ideas. The working group covered a broad range of topics including a constrained Standard Model from an extra dimension, a discussion of recent ideas addressing the strong CP problem, searches for doubly charged higgs bosons in e{gamma} collisions, and an update on discovery limits for extra neutral gauge bosons at hadron colliders. The breadth of topics rejects the many ideas and approaches to physics beyond the Standard Model.
Date: November 19, 2002
Creator: Chertok, M.; Dienes, K.; Godfrey, S.; Kalyniak, P.; Kaplan, D.; Kribs, G. D. et al.
Partner: UNT Libraries Government Documents Department

Scattering in a magnetic field

Description: The fixed target program at Fermilab has come to an end. New projects are in the planning stage. Among them is a muon storage ring. Up to the present, all storage rings in high-energy physics have carried stable particles, namely the electron and proton and their antiparticles. The muon is unstable and decays with a mean lifetime of 2.0 x 10{sup -6} sec. Two types of cooling have been used in the past. One is stochastic cooling where an electrode is used to detect the positions of the particles and send a signal to another position across the ring. Through successive applications of this technique, the phase space is ultimately greatly reduced and beams can be made to collide with a useful event rate. The second type of cooling is electron cooling. Here protons and electrons are made to travel together for a short distance. Equipartition causes transfer of transverse energy of the protons to that of the electrons. Neither of these methods is fast enough to allow acceleration of a sufficient number of muons up to maximum energy before they decay. A new method known as ionization cooling has been proposed.[1] The muons are cooled by passing them through a container of liquid hydrogen. The energy loss reduces both transverse and longitudinal momentum. The longitudinal momentum is restored with RF cavities. The net result is to maintain the longitudinal momentum while cooling the transverse momentum. To minimize the total travel distance of the muons the liquid hydrogen is placed inside the focusing solenoids. The question arises as to whether the presence of the solenoids influences the phase space occupied by the muons. After the muon scatters it has transverse momentum. In a constant longitudinal magnetic field the trajectory wraps around the field lines and coincides in momentum and position ...
Date: August 19, 2002
Creator: Carey, David C.
Partner: UNT Libraries Government Documents Department

D0 silicon trackers

Description: The present Fermilab D0 silicon microstrip tracker, the silicon microstrip tracker which was designed to replace it, and plans for upgrading the present silicon tracker are described.
Date: December 19, 2003
Creator: Cooper, W. E.
Partner: UNT Libraries Government Documents Department

Target Design Activities for Inetrial Fusion Energy at Lawrence Livermore National Laboratory

Description: The authors studied a variety of targets to be driven by ion beams or lasers in the past year. In order to relax target fabrication requirements, expand the allowed beam phase space volume and meet some radiological safety requirements, they continued to extend the set of the distributed radiator target designs for heavy ion beams. The hydrodynamic stability of a high gain directly driven laser target recently proposed at the Naval Research Laboratory has been studied. Because target chambers are sensitive to the x-ray spectrum as well as the composition and energy of the capsule debris they also present these for this target. A novel implosion scheme for the Fast Ignitor fusion scenario that minimizes the amount of coronal plasma that the igniting laser beam must penetrate is described. They describe recently derived scaling laws that relate the minimum value of the incoming fuel kinetic energy to the peak drive pressure, the fuel adiabat and the implosion velocity for capsules that use the kinetic energy of the implosion to heat the hotspot to ignition temperatures.
Date: September 19, 2000
Creator: Tabal, M; Callahan-Miller, D.; Herrmann, M.; Hatchett, S.; Lindl, J. & Perkins, L.J.
Partner: UNT Libraries Government Documents Department

Rheology Modifiers for Radioactive Waste Slurries

Description: The goals of this study were to determine if trace levels of chemical additives could be used to reduce the rheological characteristics of radioactive waste slurries, identify potential chemical additives for this work and future testing, test a limited set of chemical additive candidates on simulated radioactive wastes, and develop advanced techniques to visualize the internal slurry structure and particle-particle interaction within the slurry.
Date: February 19, 2003
Creator: Calloway, T.B. Jr.
Partner: UNT Libraries Government Documents Department