Issues in RF propagation modeling in an urban environment using the Extended Air Defense Simulation (EADSIM) mission level model. (open access)

Issues in RF propagation modeling in an urban environment using the Extended Air Defense Simulation (EADSIM) mission level model.

As military operations in urban environments become more numerous, the ability of combat units to communicate, jam enemy communications, or employ RF weapons within this environment must be evaluated. To perform this evaluation in a mission level model requires a capability to evaluate the contributions of both terrain and man-made structures (interior and exterior) to RF propagation. The present study is an analysis of the adequacy of a mission level model (EADSIM) to perform these RF propagation calculations in an urban environment. Three basic environments must be assessed. The first environment consists entirely of terrain, with no man-made features impacting propagation values. The second environment includes terrain, but also includes the contribution of solid structures with abrupt edges, which may obstruct/influence LOS paths. The third environment includes not only terrain and structures, but also contains structures with interior features which must be evaluated to determine the propagation levels within and around these structures. EADSIM was used as the model for evaluation in view of its suite of propagation tools which can be used for analysis of RF propagation between transmitters and receivers including terrain. To assess EADSIM's capability to perform in these environments, flat terrain maps with an obstruction were …
Date: February 1, 2006
Creator: Booher, Stephen R. (Teledyne Brown Engineering, Corrales, NM) & Bacon, Larry Donald
System: The UNT Digital Library
BlueGene/L Integration Project (open access)

BlueGene/L Integration Project

None
Date: February 1, 2006
Creator: Cupps, K
System: The UNT Digital Library
2005 Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site (open access)

2005 Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site

This report is a compilation of the calendar year 2005 groundwater sampling results from the Area 5 Radioactive Waste Management Site. In additon to providing groundwater monitoring results, this report also includes information regarding site hydrogeology, well construction, sample collection, and meteorological data measured at the Area 5 Radioactive Waste Management Site at the Nevada Test Site, Ny County, Nevada.
Date: February 1, 2006
Creator: Bechtel Nevada (Firm)
System: The UNT Digital Library
Genomics:GTL Contractor-Grantee Workshop IV and Metabolic Engineering Working Group Inter-Agency Conference on Metabolic Engineering 2006 (open access)

Genomics:GTL Contractor-Grantee Workshop IV and Metabolic Engineering Working Group Inter-Agency Conference on Metabolic Engineering 2006

Welcome to the 2006 joint meeting of the fourth Genomics:GTL Contractor-Grantee Workshop and the six Metabolic Engineering Working Group Inter-Agency Conference. The vision and scope of the Genomics:GTL program continue to expand and encompass research and technology issues from diverse scientific disciplines, attracting broad interest and support from researchers at universities, DOE national laboratories, and industry. Metabolic engineering's vision is the targeted and purposeful alteration of metabolic pathways to improve the understanding and use of cellular pathways for chemical transformation, energy transduction, and supramolecular assembly. These two programs have much complementarity in both vision and technological approaches, as reflected in this joint workshop. GLT's challenge to the scientific community remains the further development and use of a broad array of innovative technologies and computational tools to systematically leverage the knowledge and capabilities brought to us by DNA sequencing projects. The goal is to seek a broad and predictive understanding of the functioning and control of complex systems--individual microbes, microbial communities, and plants. GTL's prominent position at the interface of the physical, computational, and biological sciences is both a strength and challenge. Microbes remain GTL's principal biological focus. In the complex 'simplicity' of microbes, they find capabilities needed by DOE and …
Date: February 1, 2006
Creator: Mansfield, Betty Kay & Martin, Sheryl A
System: The UNT Digital Library
Preliminary Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Materials from the Columbia River (open access)

Preliminary Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Materials from the Columbia River

Dredging of the Columbia River navigation channel has raised concerns about dredging-related impacts on Dungeness crabs (Cancer magister). The overall objectives of this effort are to synthesize what is known about disposal effects on Dungeness crabs (Phase 1) and to offer approaches to quantify the effects, including approaches to gain a population-level perspective on any effects found in subsequent studies (Phase 2). This report documents Phase 1, which included (1) development of a conceptual model to integrate knowledge about crab biology and the physical processes occurring during disposal, (2) application of physics-based numerical modeling of the disposal event to understand the physical forces and processes to which a crab might be exposed during disposal, (3) conduct of a vulnerability analysis to identify the potential mechanisms by which crabs may be injured, and (4) recommendations of topics and approaches for future studies to assess the potential population-level effects of disposal on Dungeness crabs. The conceptual model first recognizes that disposal of dredged materials is a physically dynamic process with three aspects: (1) convective descent and bottom encounter, (2) dynamic collapse and spreading, and (3) mounding. Numerical modeling was used to assess the magnitude of the potentially relevant forces and extent of …
Date: February 1, 2006
Creator: Pearson, Walter H.; Miller, Martin C.; Williams, Greg D.; Kohn, Nancy P. & Skalski, John R.
System: The UNT Digital Library
Purple Integration Project (open access)

Purple Integration Project

None
Date: February 1, 2006
Creator: Hamilton, P
System: The UNT Digital Library
Advanced Gasification By-Product Utilization (open access)

Advanced Gasification By-Product Utilization

With the recent passing of new legislation designed to permanently cap and reduce mercury emissions from coal-fired utilities, it is more important than ever to develop and improve upon methods of controlling mercury emissions. One promising technique is carbon sorbent injection into the flue gas of the coal-fired power plant. Currently, this technology is very expensive as costly commercially activated carbons are used as sorbents. There is also a significant lack of understanding of the interaction between mercury vapor and the carbon sorbent, which adds to the difficulty of predicting the amount of sorbent needed for specific plant configurations. Due to its inherent porosity and adsorption properties as well as on-site availability, carbons derived from gasifiers are potential mercury sorbent candidates. Furthermore, because of the increasing restricted use of landfilling, the coal industry is very interested in finding uses for these materials as an alternative to the current disposal practice. The results of laboratory investigations and supporting technical assessments conducted under DOE Subcontract No. DE-FG26-03NT41795 are reported for the period September 1, 2004 to August 31, 2005. This contract is with the University of Kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Research …
Date: February 1, 2006
Creator: Andrews, Rodney; Rubel, Aurora; Groppo, Jack; Geertsema, Ari; Huggins, Frank; Maroto-Valer, M. Mercedes et al.
System: The UNT Digital Library
A framework and methodology for nuclear fuel cycle transparency. (open access)

A framework and methodology for nuclear fuel cycle transparency.

A key objective to the global deployment of nuclear technology is maintaining transparency among nation-states and international communities. By providing an environment in which to exchange scientific and technological information regarding nuclear technology, the safe and legitimate use of nuclear material and technology can be assured. Many nations are considering closed or multiple-application nuclear fuel cycles and are subsequently developing advanced reactors in an effort to obtain some degree of energy self-sufficiency. Proliferation resistance features that prevent theft or diversion of nuclear material and reduce the likelihood of diversion from the civilian nuclear power fuel cycle are critical for a global nuclear future. IAEA Safeguards have been effective in minimizing opportunities for diversion; however, recent changes in the global political climate suggest implementation of additional technology and methods to ensure the prompt detection of proliferation. For a variety of reasons, nuclear facilities are becoming increasingly automated and will require minimum manual operation. This trend provides an opportunity to utilize the abundance of process information for monitoring proliferation risk, especially in future facilities. A framework that monitors process information continuously can lead to greater transparency of nuclear fuel cycle activities and can demonstrate the ability to resist proliferation associated with these …
Date: February 1, 2006
Creator: McClellan, Yvonne; York, David L.; Inoue, Naoko (Japan Atomic Energy Agency, Ibaraki, Japan); Love, Tracia L. & Rochau, Gary Eugene
System: The UNT Digital Library
Progress toward a MEMS fabricated 100 GHz oscillator. (open access)

Progress toward a MEMS fabricated 100 GHz oscillator.

This report summarizes an LDRD effort which looked at the feasibility of building a MEMS (Micro-Electro-Mechanical Systems) fabricated 100 GHz micro vacuum tube. PIC Simulations proved to be a very useful tool in investigating various device designs. Scaling parameters were identified. This in turn allowed predictions of oscillator growth based on beam parameters, cavity geometry, and cavity loading. The electron beam source was identified as a critical element of the design. FEA's (Field Emission Arrays) were purchased to be built into the micro device. Laboratory testing of the FEA's was also performed which pointed out care and handling issues along with maximum current capabilities. Progress was made toward MEMS fabrication of the device. Techniques were developed and successfully employed to build up several of the subassemblies of the device. However, the lower wall fabrication proved to be difficult and a successful build was not completed. Alternative approaches to building this structure have been identified. Although these alternatives look like good solutions for building the device, it was not possible to complete a redesign and build during the timeframe of this effort.
Date: February 1, 2006
Creator: Loubriel, Guillermo Manuel; Lemp, Thomas; Weyn, Mark L.; Coleman, Phillip Dale & Rowley, James E. (SAIC, Albuquerque, NM)
System: The UNT Digital Library
Development of Cost-Effective Low-Permeability Ceramic and Refractory Components for Aluminum Melting and Casting (open access)

Development of Cost-Effective Low-Permeability Ceramic and Refractory Components for Aluminum Melting and Casting

A recent review by the U.S. Advanced Ceramics Association, the Aluminum Association, and the U.S. Department of Energy's Office of Industrial Technologies (DOE/OIT) described the status of advanced ceramics for aluminum processing, including monolithics, composites, and coatings. The report observed that monolithic ceramics (particularly oxides) have attractive properties such as resistance to heat, corrosion, thermal shock, abrasion, and erosion [1]. However, even after the developments of the past 25 years, there are two key barriers to commercialization: reliability and cost-effectiveness. Industry research is therefore focused on eliminating these barriers. Ceramic coatings have likewise undergone significant development and a variety of processes have been demonstrated for applying coatings to substrates. Some processes, such as thermal barrier coatings for gas turbine engines, exhibit sufficient reliability and service life for routine commercial use. Worldwide, aluminum melting and molten metal handling consumes about 506,000 tons of refractory materials annually. Refractory compositions for handling molten aluminum are generally based on dense fused cast silica or mullite. The microstructural texture is extremely important because an interlocking mass of coarser grains must be bonded together by smaller grains in order to achieve adequate strength. At the same time, well-distributed microscopic pores and cracks are needed to deflect …
Date: February 1, 2006
Creator: Kadolkar, Puja & Ott, Ronald D
System: The UNT Digital Library
Comparison of the present and planned operation of the SIS18 and the AGS Booster with intermediate charge state heavy ions (open access)

Comparison of the present and planned operation of the SIS18 and the AGS Booster with intermediate charge state heavy ions

N/A
Date: February 1, 2006
Creator: A., Smolyakov; Fischer, W.; Omet, C. & Spiller, P.
System: The UNT Digital Library
Evaluation of Salmon Spawning below the Four Lowermost Columbia River Dams, 2004-2005 Annual Report. (open access)

Evaluation of Salmon Spawning below the Four Lowermost Columbia River Dams, 2004-2005 Annual Report.

Since FY 2000, scientists at Pacific Northwest National Laboratory (PNNL) have conducted research to assess the extent of spawning by chum (Oncorhynchus keta) and fall Chinook (O. tshawytscha) salmon in the lower mainstem Columbia River. Their work supports a larger Bonneville Power Administration (BPA) project aimed at characterizing the physical habitat used by mainstem fall Chinook and chum salmon populations. Multiple collaborators in addition to PNNL are involved in the BPA project--counterparts include the Washington Department of Fish and Wildlife (WDFW), U.S. Fish and Wildlife Service (USFWS), Pacific States Marine Fisheries Commission (PSMFC), U.S. Geological Survey (USGS), and Oregon Department of Fish and Wildlife (ODFW). Data resulting from the individual tasks each agency conducts are providing a sound scientific basis for developing strategies to operate the Federal Columbia River Power System (FCRPS) in ways that will effectively protect and enhance the chum and fall Chinook salmon populations--both listed as threatened under the Endangered Species Act. Fall Chinook salmon, thought to originate from Bonneville Hatchery, were first noted to be spawning downstream of Bonneville Dam by biologists from the WDFW in 1993. Known spawning areas include gravel beds on the Washington side of the river near Hamilton Creek and Ives Island. …
Date: February 1, 2006
Creator: Geist, David & Currie, Andrea
System: The UNT Digital Library
Fast Extraction from the Booster to R Line using Two Kicks from the F3 Kicker (open access)

Fast Extraction from the Booster to R Line using Two Kicks from the F3 Kicker

N/A
Date: February 1, 2006
Creator: K., Zeno
System: The UNT Digital Library
Helium bubble linkage and the transition to rapid He release in aging Pd tritide. (open access)

Helium bubble linkage and the transition to rapid He release in aging Pd tritide.

A model is presented for the linking of helium bubbles growing in aging metal tritides. Stresses created by neighboring bubbles are found to produce bubble growth toward coalescence. This process is interrupted by the fracture of ligaments between bubble arrays. The condition for ligament fracture percolates through the material to reach external surfaces, leading to material micro-cracking and the release of helium within the linked-bubble cluster. A comparison of pure coalescence and pure fracture mechanisms shows the critical HeM concentration for bubble linkage is not strongly dependent on details of the linkage process. The combined stress-directed growth and fracture process produces predictions for the onset of rapid He release and the He emission rate. Transition to this rapid release state is determined from the physical size of the linked-bubble clusters, which is calculated from dimensional invariants in classical percolation theory. The result is a transition that depends on material dimensions. The onset of bubble linkage and rapid He release are found to be quite sensitive to the bubble spacing distribution, which is log-normal for bubbles nucleated by self-trapping.
Date: February 1, 2006
Creator: Cowgill, Donald F.
System: The UNT Digital Library
Solving the quasi-static field model of the pulse-line accelerator; relationship to a circuit model (open access)

Solving the quasi-static field model of the pulse-line accelerator; relationship to a circuit model

The Pulse-Line Ion Accelerator (PLIA) is a promising approach to high-gradient acceleration of an ion beam at high line charge density [1, 2, 3, 4, 5, 6]. A recent note by R. J. Briggs [7] suggests that a ''sheath helix'' model of such a system can be solved numerically in the quasi-static limit. Such a model captures the correct macroscopic behavior from ''first principles'' without the need to time-advance the full Maxwell equations on a grid. This note describes numerical methods that may be used to effect such a solution, and their connection to the circuit model that was described in an earlier note by the author [8]. Fine detail of the fields in the vicinity of the helix wires is not obtained by this approach, but for purposes of beam dynamics simulation such detail is not generally needed.
Date: February 1, 2006
Creator: Friedman, A
System: The UNT Digital Library
Characterization of Slag, Fly Ash and Portland Cement for Saltstone (open access)

Characterization of Slag, Fly Ash and Portland Cement for Saltstone

Batch-to-batch variability in the chemical and physical properties of the fly ash, slag and portland cement (binders) will be an ongoing concern over the many years that salt waste from Tank 50 will be processed into grout at the Saltstone Processing Facility. This batch-to-batch variability in the properties of the binder materials translates to variability in the fresh and cured properties of Saltstone. Therefore, it is important to quantify the batch-to-batch variability of the binder materials and the resultant variation in grout properties. This report is the starting point for that process by providing the baseline (reference point) binder properties to which future batches of binder materials can be compared. For this characterization effort, properties of fly ash, slag and portland cement were obtained and documented in this report. These properties included particle size distribution by laser light scattering and dry sieving, particle size and morphology by scanning electron microscopy, true, aerated and tapped densities, chemical composition, rheological properties of the water based slurries made from individual binder material, and volatility through thermogravimetric analysis and differential thermal analysis. The properties presented in this report also provide a baseline data set to assist in problem solving efforts when or if unanticipated …
Date: February 1, 2006
Creator: Harbour, J
System: The UNT Digital Library
Quantum Well Thermoelectrics for Converting Waste Heat to Electricity Quarterly Technical Progress Report: October 2005 - January 2006 (open access)

Quantum Well Thermoelectrics for Converting Waste Heat to Electricity Quarterly Technical Progress Report: October 2005 - January 2006

New thermoelectric materials using Quantum Well (QW) technology are expected to increase the energy conversion efficiency to more than 25% from the present 5%, which will allow for the low cost conversion of waste heat into electricity. Hi-Z Technology, Inc. has been developing QW technology over the past six years. It will use Caterpillar, Inc., a leader in the manufacture of large scale industrial equipment, for verification and life testing of the QW films and modules. Other members of the team are Pacific Northwest National Laboratory, who will sputter large area QW films. The Scope of Work is to develop QW materials from their present proof-of-principle technology status to a pre-production level over a proposed three year period. This work will entail fabricating the QW films through a sputtering process of 50 {micro}m thick multi layered films and depositing them on 12 inch diameter, 5 {micro}m thick Si substrates. The goal in this project is to produce the technology for fabricating a basic 10-20 watt module that can be used to build up any size generator such as: a 5-10 kW Auxiliary Power Unit (APU), a multi kW Waste Heat Recovery Generator (WHRG) for a class 8 truck or as …
Date: February 1, 2006
Creator: Ghamaty, Saeid
System: The UNT Digital Library
Verification and Uncertainty Reduction of Amchitka Underground Nuclear Testing Models (open access)

Verification and Uncertainty Reduction of Amchitka Underground Nuclear Testing Models

The modeling of Amchitka underground nuclear tests conducted in 2002 is verified and uncertainty in model input parameters, as well as predictions, has been reduced using newly collected data obtained by the summer 2004 field expedition of CRESP. Newly collected data that pertain to the groundwater model include magnetotelluric (MT) surveys conducted on the island to determine the subsurface salinity and porosity structure of the subsurface, and bathymetric surveys to determine the bathymetric maps of the areas offshore from the Long Shot and Cannikin Sites. Analysis and interpretation of the MT data yielded information on the location of the transition zone, and porosity profiles showing porosity values decaying with depth. These new data sets are used to verify the original model in terms of model parameters, model structure, and model output verification. In addition, by using the new data along with the existing data (chemistry and head data), the uncertainty in model input and output is decreased by conditioning on all the available data. A Markov Chain Monte Carlo (MCMC) approach is adapted for developing new input parameter distributions conditioned on prior knowledge and new data. The MCMC approach is a form of Bayesian conditioning that is constructed in such …
Date: February 1, 2006
Creator: Hassan, Ahmed & Chapman, Jenny
System: The UNT Digital Library
Initial Demonstration of Mercury Wavefront Correction System (open access)

Initial Demonstration of Mercury Wavefront Correction System

High average power operation of the Mercury Laser induces dynamic aberrations to the laser beam wavefront. Analysis of recent data indicates that up to 4 waves of low order aberration (mainly focus error or power, with spatial resolution < 0.5 cm{sup -1}) could be expected at each pass. Because of the magnitude of the wavefront error, the logical position is to place a deformable mirror (DM) at the M11 position, where the DM will correct the beam between passes 1 & 2 and 3 & 4. Currently, there are only two established commercial vendors offering complete adaptive optic (AO) systems that can accommodate the Mercury beam size (45 x 75 mm) which are compatible with high damage threshold coatings. Xinetics (MA, USA) offers a complete AO system along with a Shack-Hartmann wavefront sensor. The Xinetics DM is based on lead magnesium niobate (PMN) technology. A number of US aerospace firms as well as NIF use Xinetics PMN technology for their DMs. Phasics (Paris, France) offers a complete AO solution with its proprietary SID-4, a four-way shearing interferometric wavefront sensor capable of high resolution (over 100 x 100 sampling points). The Phasics system includes a bimorph deformable mirror from Night-n-Opt (Moscow, …
Date: February 1, 2006
Creator: Liao, Z. M.
System: The UNT Digital Library
A Study of Stranding of Juvenile Salmon by Ship Wakes Along the Lower Columbia River Using a Before-and-After Design: Before-Phase Results (open access)

A Study of Stranding of Juvenile Salmon by Ship Wakes Along the Lower Columbia River Using a Before-and-After Design: Before-Phase Results

Ship wakes produced by deep-draft vessels transiting the lower Columbia River have been observed to cause stranding of juvenile salmon. Proposed deepening of the Columbia River navigation channel has raised concerns about the potential impact of the deepening project on juvenile salmon stranding. The Portland District of the U.S. Army Corps of Engineers requested that the Pacific Northwest National Laboratory design and conduct a study to assess stranding impacts that may be associated with channel deepening. The basic study design was a multivariate analysis of covariance of field observations and measurements under a statistical design for a before and after impact comparison. We have summarized field activities and statistical analyses for the ?before? component of the study here. Stranding occurred at all three sampling sites and during all three sampling seasons (Summer 2004, Winter 2005, and Spring 2005), for a total of 46 stranding events during 126 observed vessel passages. The highest occurrence of stranding occurred at Barlow Point, WA, where 53% of the observed events resulted in stranding. Other sites included Sauvie Island, OR (37%) and County Line Park, WA (15%). To develop an appropriate impact assessment model that accounted for relevant covariates, regression analyses were conducted to determine …
Date: February 1, 2006
Creator: Pearson, Walter H.; Skalski, J R.; Sobocinski, Kathryn L.; Miller, Martin C.; Johnson, Gary E.; Williams, Greg D. et al.
System: The UNT Digital Library
1/6TH SCALE STRIP EFFLUENT FEED TANK-MIXING RESULTS USING MCU SOLVENT (open access)

1/6TH SCALE STRIP EFFLUENT FEED TANK-MIXING RESULTS USING MCU SOLVENT

The purpose of this task was to determine if mixing was an issue for the entrainment and dispersion of the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) solvent in the Defense Waste Processing Facility (DWPF) Strip Effluent Feed Tank (SEFT). The MCU strip effluent stream containing the Cs removed during salt processing will be transferred to the DWPF for immobilization in HLW glass. In lab-scale DWPF chemical process cell testing, mixing of the solvent in the dilute nitric acid solution proved problematic, and the Savannah River National Laboratory (SRNL) was requested to perform scaled SEFT mixing tests to evaluate whether the problem was symptomatic of the lab-scale set-up or of the solvent. The solvent levels tested were 228 and 235 ppm, which represented levels near the estimated DWPF solvent limit of 239 ppm in 0.001M HNO{sub 3} solution. The 239 ppm limit was calculated by Norato in X-CLC-S-00141. The general approach for the mixing investigation was to: (1) Investigate the use of fluorescent dyes to aid in observing the mixing behavior. Evaluate and compare the physical properties of the fluorescent dyed MCU solvents to the baseline Oak Ridge CSSX solvent. Based on the data, use the dyed MCU solvent …
Date: February 1, 2006
Creator: Hansen, E.
System: The UNT Digital Library
Operational characteristics and analysis of the immersed-Bz diode on RITS-3. (open access)

Operational characteristics and analysis of the immersed-Bz diode on RITS-3.

The immersed-B{sub z} diode is being developed as a high-brightness, flash x-ray radiography source. This diode is a foil-less electron-beam diode with a long, thin, needle-like cathode inserted into the bore of a solenoid. The solenoidal magnetic field guides the electron beam emitted from the cathode to the anode while maintaining a small beam radius. The electron beam strikes a thin, high-atomic-number anode and produces bremsstrahlung. We report on an extensive series of experiments where an immersed-B{sub z} diode was fielded on the RITS-3 pulsed power accelerator, a 3-cell inductive voltage generator that produced peak voltages between 4 and 5 MV, {approx}140 kA of total current, and power pulse widths of {approx}50 ns. The diode is a high impedance device that, for these parameters, nominally conducts {approx}30 kA of electron beam current. Diode operating characteristics are presented and two broadly characterized operating regimes are identified: a nominal operating regime where the total diode current is characterized as classically bipolar and an anomalous impedance collapse regime where the total diode current is in excess of the bipolar limit and up to the full accelerator current. The operating regimes are approximately separated by cathode diameters greater than {approx}3 mm for the nominal …
Date: February 1, 2006
Creator: Bruner, Nichelle "Nicki"; Oliver, Bryan Velten; Portillo, Salvador; Puetz, Elizabeth A.; Johnston, Mark D.; Welch, Dale Robert et al.
System: The UNT Digital Library
Hybrid Electric Vehicle End-Of-Life Testing On Honda Insights, Gen I Civics And Toyota Gen I Priuses (open access)

Hybrid Electric Vehicle End-Of-Life Testing On Honda Insights, Gen I Civics And Toyota Gen I Priuses

This technical report details the end-of-life fuel efficiency and battery testing on two model year 2001 Honda Insight hybrid electric vehicles (HEVs), two model year 2003 Honda Civic HEVs, and two model year 2002 Toyota Prius HEVs. The end-of-life testing was conducted after each vehicle has been operated for approximately 160,000 miles. This testing was conducted by the U.S. Department of Energy’s (DOE) Advanced Vehicle Testing Activity (AVTA). The AVTA is part of DOE’s FreedomCAR and Vehicle Technologies Program. SAE J1634 fuel efficiency testing was performed on the six HEVs with the air conditioning (AC) on and off. The AC on and off test results are compared to new vehicle AC on and off fuel efficiencies for each HEV model. The six HEVs were all end-of-life tested using new-vehicle coast down coefficients. In addition, one of each HEV model was also subjected to fuel efficiency testing using coast down coefficients obtained when the vehicles completed 160,000 miles of fleet testing. Traction battery pack capacity and power tests were also performed on all six HEVs during the end-of-life testing in accordance with the FreedomCAR Battery Test Manual For Power-Assist Hybrid Electric Vehicles procedures. When using the new-vehicle coast down coefficients (Phase …
Date: February 1, 2006
Creator: Francfort, James; Karner, Donald; Harkins, Ryan & Tardiolo, Joseph
System: The UNT Digital Library
Quantum coherence in semiconductor nanostructures for improved lasers and detectors. (open access)

Quantum coherence in semiconductor nanostructures for improved lasers and detectors.

The potential for implementing quantum coherence in semiconductor self-assembled quantum dots has been investigated theoretically and experimentally. Theoretical modeling suggests that coherent dynamics should be possible in self-assembled quantum dots. Our experimental efforts have optimized InGaAs and InAs self-assembled quantum dots on GaAs for demonstrating coherent phenomena. Optical investigations have indicated the appropriate geometries for observing quantum coherence and the type of experiments for observing quantum coherence have been outlined. The optical investigation targeted electromagnetically induced transparency (EIT) in order to demonstrate an all optical delay line.
Date: February 1, 2006
Creator: Chow, Weng Wah; Lyo, Sungkwun Kenneth; Cederberg, Jeffrey George; Modine, Normand Arthur & Biefeld, Robert Malcolm
System: The UNT Digital Library