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194,006 Matching Results
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Nonproliferation and Knowledge Security Course
N/A
Date:
October 1, 2014
Creator:
D., Verdugo & U., Rohatgi
Object Type:
Article
System:
The UNT Digital Library
Virginia Offshore Wind Cost Reduction Through Innovation Study (VOWCRIS) (Poster)
The VOWCRIS project is an integrated systems approach to the feasibility-level design, performance, and cost-of-energy estimate for a notional 600-megawatt offshore wind project using site characteristics that apply to the Wind Energy Areas of Virginia, Maryland and North Carolina.
Date:
October 1, 2014
Creator:
Maples, B.; Campbell, J. & Arora, D.
Object Type:
Article
System:
The UNT Digital Library
Design Analysis and Manufacturing Studies for ITER In-Vessel Coils
ITER is incorporating two types of In Vessel Coils (IVCs): ELM Coils to mitigate Edge Localized Modes and VS Coils to provide Vertical Stabilization of the plasma. Strong coupling with the plasma is required so that the ELM and VS Coils can meet their performance requirements. Accordingly, the IVCs are in close proximity to the plasma, mounted just behind the Blanket Shield Modules. This location results in a radiation and temperature environment that is severe necessitating new solutions for material selection as well as challenging analysis and design solutions. Fitting the coil systems in between the blanket shield modules and the vacuum vessel leads to difficult integration with diagnostic cabling and cooling water manifolds.
Date:
July 1, 2014
Creator:
Kalish, M.; Heitzenroeder, P.; Neumeyer, C.; Titus, P.; Zhai, Y.; Zatz, I. et al.
Object Type:
Article
System:
The UNT Digital Library
The Low-Frequency Radio Catalog of Flat Spectrum Sources
None
Date:
May 1, 2014
Creator:
Massaro, F.; Giroletti, M.; D'Abrusco, R.; Masetti, N.; Paggi, A.; Cowperthwaite, Philip S. et al.
Object Type:
Article
System:
The UNT Digital Library
Case Study: Mobile Photovoltaic System at Bechler Meadows Ranger Station, Yellowstone National Park (Brochure)
The mobile PV/generator hybrid system deployed at Bechler Meadows provides a number of advantages. It reduces on-site air emissions from the generator. Batteries allow the generator to operate only at its rated power, reducing run-time and fuel consumption. Energy provided by the solar array reduces fuel consumption and run-time of the generator. The generator is off for most hours providing peace and quiet at the site. Maintenance trips from Mammoth Hot Springs to the remote site are reduced. The frequency of intrusive fuel deliveries to the pristine site is reduced. And the system gives rangers a chance to interpret Green Park values to the visiting public. As an added bonus, the system provides all these benefits at a lower cost than the basecase of using only a propane-fueled generator, reducing life cycle cost by about 26%.
Date:
March 1, 2014
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Developing Spent Fuel Assembly for Advanced NDA Instrument Calibration - NGSI Spent Fuel Project
None
Date:
March 1, 2014
Creator:
Hu, Jianwei; Gauld, Ian C; Banfield, James & Skutnik, Steven
Object Type:
Report
System:
The UNT Digital Library
The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers
The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the …
Date:
March 1, 2014
Creator:
Mamum, Md Abdullah A.; Elmustafa, Abdelmageed A,; Stutzman, Marcy L.; Adderley, Philip A. & Poelker, Matthew
Object Type:
Article
System:
The UNT Digital Library
Energy Savings and Peak Demand Reduction of a SEER 21 Heat Pump vs. a SEER 13 Heat Pump with Attic and Indoor Duct Systems
This report describes results of experiments that were conducted in an unoccupied 1600 square foot house--the Manufactured Housing (MH Lab) at the Florida Solar Energy Center (FSEC)--to evaluate the delivered performance as well as the relative performance of a SEER 21 variable capacity heat pump versus a SEER 13 heat pump. The performance was evaluated with two different duct systems: a standard attic duct system and an indoor duct system located in a dropped-ceiling space.
Date:
March 1, 2014
Creator:
Cummings, J. & Withers, C.
Object Type:
Report
System:
The UNT Digital Library
HTR-PROTEUS PEBBLE BED EXPERIMENTAL PROGRAM CORE 4: RANDOM PACKING WITH A 1:1 MODERATOR-TO-FUEL PEBBLE RATIO
In its deployment as a pebble bed reactor (PBR) critical facility from 1992 to 1996, the PROTEUS facility was designated as HTR-PROTEUS. This experimental program was performed as part of an International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) on the Validation of Safety Related Physics Calculations for Low Enriched HTGRs. Within this project, critical experiments were conducted for graphite moderated LEU systems to determine core reactivity, flux and power profiles, reaction-rate ratios, the worth of control rods, both in-core and reflector based, the worth of burnable poisons, kinetic parameters, and the effects of moisture ingress on these parameters. One benchmark experiment was evaluated in this report: Core 4. Core 4 represents the only configuration with random pebble packing in the HTR-PROTEUS series of experiments, and has a moderator-to-fuel pebble ratio of 1:1. Three random configurations were performed. The initial configuration, Core 4.1, was rejected because the method for pebble loading, separate delivery tubes for the moderator and fuel pebbles, may not have been completely random; this core loading was rejected by the experimenters. Cores 4.2 and 4.3 were loaded using a single delivery tube, eliminating the possibility for systematic ordering effects. The second and third cores differed slightly …
Date:
March 1, 2014
Creator:
Bess, John D. & Montierth, Leland M.
Object Type:
Report
System:
The UNT Digital Library
HTR-PROTEUS PEBBLE BED EXPERIMENTAL PROGRAM CORES 9 & 10: COLUMNAR HEXAGONAL POINT-ON-POINT PACKING WITH A 1:1 MODERATOR-TO-FUEL PEBBLE RATIO
PROTEUS is a zero-power research reactor based on a cylindrical graphite annulus with a central cylindrical cavity. The graphite annulus remains basically the same for all experimental programs, but the contents of the central cavity are changed according to the type of reactor being investigated. Through most of its service history, PROTEUS has represented light-water reactors, but from 1992 to 1996 PROTEUS was configured as a pebble-bed reactor (PBR) critical facility and designated as HTR-PROTEUS. The nomenclature was used to indicate that this series consisted of High Temperature Reactor experiments performed in the PROTEUS assembly. During this period, seventeen critical configurations were assembled and various reactor physics experiments were conducted. These experiments included measurements of criticality, differential and integral control rod and safety rod worths, kinetics, reaction rates, water ingress effects, and small sample reactivity effects (Ref. 3). HTR-PROTEUS was constructed, and the experimental program was conducted, for the purpose of providing experimental benchmark data for assessment of reactor physics computer codes. Considerable effort was devoted to benchmark calculations as a part of the HTR-PROTEUS program. References 1 and 2 provide detailed data for use in constructing models for codes to be assessed. Reference 3 is a comprehensive summary of …
Date:
March 1, 2014
Creator:
Bess, John D.
Object Type:
Report
System:
The UNT Digital Library
NEUTRON RADIOGRAPHY (NRAD) REACTOR 64-ELEMENT CORE UPGRADE
The neutron radiography (NRAD) reactor is a 250 kW TRIGA (registered) (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The interim critical configuration developed during the core upgrade, which contains only 62 fuel elements, has been evaluated as an acceptable benchmark experiment. The final 64-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has also been evaluated as an acceptable benchmark experiment. Calculated eigenvalues differ significantly (approximately +/-1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.
Date:
March 1, 2014
Creator:
Bess, John D.
Object Type:
Report
System:
The UNT Digital Library
Understanding Mechanisms of Radiological Contamination
Over the last 50 years, the study of radiological contamination and decontamination has expanded significantly. This paper addresses the mechanisms of radiological contamination that have been reported and then discusses which methods have recently been used during performance testing of several different decontamination technologies. About twenty years ago the Idaho Nuclear Technology Engineering Center (INTEC) at the INL began a search for decontamination processes which could minimize secondary waste. In order to test the effectiveness of these decontamination technologies, a new simulated contamination, termed SIMCON, was developed. SIMCON was designed to replicate the types of contamination found on stainless steel, spent fuel processing equipment. Ten years later, the INL began research into methods for simulating urban contamination resulting from a radiological dispersal device (RDD). This work was sponsored by the Defense Advanced Research Projects Agency (DARPA) and included the initial development an aqueous application of contaminant to substrate. Since 2007, research sponsored by the US Environmental Protection Agency (EPA) has advanced that effort and led to the development of a contamination method that simulates particulate fallout from an Improvised Nuclear Device (IND). The IND method diverges from previous efforts to create tenacious contamination by simulating a reproducible “loose” contamination. Examining …
Date:
March 1, 2014
Creator:
Demmer, Rick; Drake, John & Ryan James, PhD
Object Type:
Article
System:
The UNT Digital Library
US DOE-EM On-Site Disposal Cell Working Group - Fostering Communication On Performance Assessment Challenges
On-site disposal cells are in use and being considered at several U.S. Department of Energy (USDOE) sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These facilities are typically developed with regulatory oversight from States and/or the US Environmental Protection Agency (USEPA) in addition to USDOE. The facilities are developed to meet design standards for disposal of hazardous waste as well as the USDOE performance based standards for disposal of radioactive waste. The involvement of multiple and different regulators for facilities across separate sites has resulted in some differences in expectations for performance assessments and risk assessments (PA/RA) that are developed for the disposal facilities. The USDOE-EM Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to performance and risk assessments in support of a Record of Decision and Disposal Authorization Statement. The working group holds teleconferences, as needed, focusing on specific topics of interest. The topics addressed to date include an assessment of the …
Date:
March 1, 2014
Creator:
Seitz, Roger R.; Suttora, Linda C. & Phifer, Mark
Object Type:
Article
System:
The UNT Digital Library
Advanced Fuels Campaign Light Water Reactor Accident Tolerant Fuel Performance Metrics Executive Summary
Research and development (R&D) activities on advanced, higher performance Light Water Reactor (LWR) fuels have been ongoing for the last few years. Following the unfortunate March 2011 events at the Fukushima Nuclear Power Plant in Japan, the R&D shifted toward enhancing the accident tolerance of LWRs. Qualitative attributes for fuels with enhanced accident tolerance, such as improved reaction kinetics with steam resulting in slower hydrogen generation rate, provide guidance for the design and development of fuels and cladding with enhanced accident tolerance. A common set of technical metrics should be established to aid in the optimization and down selection of candidate designs on a more quantitative basis. “Metrics” describe a set of technical bases by which multiple concepts can be fairly evaluated against a common baseline and against one another. This report describes a proposed technical evaluation methodology that can be applied to evaluate the ability of each concept to meet performance and safety goals relative to the current UO2 – zirconium alloy system and relative to one another. The resultant ranked evaluation can then inform concept down-selection, such that the most promising accident tolerant fuel design option(s) can continue to be developed toward qualification.
Date:
February 1, 2014
Creator:
Bragg-Sitton, Shannon
Object Type:
Report
System:
The UNT Digital Library
Advanced Models and Controls for Prediction and Extension of Battery Lifetime
Predictive models of capacity and power fade must consider a multiplicity of degradation modes experienced by Li-ion batteries in the automotive environment. Lacking accurate models and tests, lifetime uncertainty must presently be absorbed by overdesign and excess warranty costs. To reduce these costs and extend life, degradation models are under development that predict lifetime more accurately and with less test data. The lifetime models provide engineering feedback for cell, pack and system designs and are being incorporated into real-time control strategies.
Date:
February 1, 2014
Creator:
Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G. & Pesaran, A.
Object Type:
Presentation
System:
The UNT Digital Library
Advancing Concentrating Solar Power Research (Fact Sheet)
Researchers at the National Renewable Energy Laboratory (NREL) provide scientific, engineering, and analytical expertise to help advance innovation in concentrating solar power (CSP). This fact sheet summarizes how NREL is advancing CSP research.
Date:
February 1, 2014
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Analysis Of Post-Wet-Chemistry Heat Treatment Effects On Nb SRF Surface Resistance
Most of the current research in superconducting radio frequency (SRF) cavities is focused on ways to reduce the construction and operating cost of SRF-based accelerators as well as on the development of new or improved cavity processing techniques. The increase in quality factors is the result of the reduction of the surface resistance of the materials. A recent test on a 1.5 GHz single cell cavity made from ingot niobium of medium purity and heat treated at 1400 {degrees}C in a ultra-high vacuum induction furnace resulted in a residual resistance of ~ 1n{Ohm} and a quality factor at 2.0 K increasing with field up to ~ 5×10{sup}10 at a peak magnetic field of 90 mT. In this contribution, we present some results on the investigation of the origin of the extended Q{SUB 0}-increase, obtained by multiple HF rinses, oxypolishing and heat treatment of all Nb cavities.
Date:
February 1, 2014
Creator:
Dhakal, Pashupati; Ciovati, Gianluigi; Kneisel, Peter K. & Myneni, Ganapati Rao
Object Type:
Article
System:
The UNT Digital Library
CALiPER Retail Lamps Study 3
The CALiPER program first began investigating LED lamps sold at retail stores in 2010, purchasing 33 products from eight retailers and covering six product categories. The findings revealed a fragmented marketplace, with large disparities in performance of different products, accuracy of manufacturer claims, and offerings from different retail outlets. Although there were some good products, looking back many would not be considered viable competitors to other available options, with too little lumen output, not high enough efficacy, or poor color quality. CALiPER took another look in late 2011purchasing 38 products of five different types from nine retailers and the improvement was marked. Performance was up; retailer claims were more accurate; and the price per lumen and price per unit efficacy were down, although the price per product had not changed much. Nonetheless, there was still plenty of room for improvement, with the performance of LED lamps not yet reaching that of well-established classes of conventional lamps (e.g., 75 W incandescent A19 lamps). Since the second retail lamp study was published in early 2012, there has been substantial progress in all aspects of LED lamps available from retailers. To document this progress, CALiPER again purchased a sample of lamps from retail …
Date:
February 1, 2014
Creator:
Royer, Michael P. & Beeson, Tracy A.
Object Type:
Report
System:
The UNT Digital Library
Cascade Apartments - Deep Energy Multifamily Retrofit , Kent, Washington (Fact Sheet)
In December of 2009-10, King County Housing Authority (KCHA) implemented energy retrofit improvements in the Cascade multifamily community, located in Kent, Washington (marine climate.)This research effort involved significant coordination from stakeholders KCHA, WA State Department of Commerce, utility Puget Sound Energy, and Cascade tenants. This report focuses on the following three primary BA research questions : 1. What are the modeled energy savings using DOE low income weatherization approved TREAT software? 2. How did the modeled energy savings compare with measured energy savings from aggregate utility billing analysis? 3. What is the Savings to Investment Ratio (SIR) of the retrofit package after considering utility window incentives and KCHA capitol improvement funding.
Date:
February 1, 2014
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
CEBAF Upgrade: Cryomodule Performance And Lessons Learned
The Thomas Jefferson National Accelerator Facility is currently engaged in the 12 GeV Upgrade Project. The goal of the 12 GeV Upgrade is a doubling of the available beam energy of the Continuous Electron Beam Accelerator Facility (CEBAF) from 6 GeV to 12 GeV. This increase in beam energy will be due in large part to the addition of ten C100 cryomodules plus associated new RF in the CEBAF linacs. The C100 cryomodules are designed to deliver 100 MeV per installed cryomodule. Each C100 cryomodule is built around a string of eight seven-cell, electro-polished, superconducting RF cavities. While an average performance of 100MV per cryomodule is needed to achieve the overall 12 GeV beam energy goal, the actual performance goal for the cryomodules is an average energy gain of 108 MV to provide operational headroom. Cryomodule production started in December 2010. All ten of the C100 cryomodules are installed in the linac tunnels and are on schedule to complete commissioning by September 2013. Performance during Commissioning has ranged from 104 MV to 118 MV. In May, 2012 a test of an early C100 achieved 108 MV with full beam loading. This paper will discuss the performance of the C100 cryomodules …
Date:
February 1, 2014
Creator:
Drury, Michael A.; Davis, G. Kirk; Hogan, John P.; Hovater, J. Curt; king@jlab.org, Lawrence; Marhauser, Frank et al.
Object Type:
Article
System:
The UNT Digital Library
Characterization and Fabrication of Spoke Cavities for High-Velocity Applications
A 500 MHz, velocity-of-light, two-spoke cavity has been designed and optimized for possible use in a compact light source. Here we present the mechanical analysis and steps taken in fabrication of this cavity at Jefferson Lab.
Date:
February 1, 2014
Creator:
Hopper, Christopher S.; Park, HyeKyoung & Delayen, Jean R.
Object Type:
Article
System:
The UNT Digital Library
Characterization Of Superconducting Samples With SIC System For Thin Film Developments: Status And Recent Results
Within any thin film development program directed towards SRF accelerating structures, there is a need for an RF characterization device that can provide information about RF properties of small samples. The current installation of the RF characterization device at Jefferson Lab is Surface Impedance Characterization (SIC) system. The data acquisition environment for the system has recently been improved to allow for automated measurement, and the system has been routinely used for characterization of bulk Nb, films of Nb on Cu, MgB$_{2}$, NbTiN, Nb$_{3}$Sn films, etc. We present some of the recent results that illustrate present capabilities and limitations of the system.
Date:
February 1, 2014
Creator:
Phillips, H. Lawrence; Reece, Charles E.; Valente-Feliciano, Anne-Marie; Xiao, Binping & Eremeev, Grigory V.
Object Type:
Article
System:
The UNT Digital Library
Clean Energy Application Centers: Annual Metrics Report for Fiscal Year 2012
This report talks about Clean Energy Application Centers: Annual Metrics Report for Fiscal Year 2012
Date:
February 1, 2014
Creator:
Schweitzer, Martin
Object Type:
Report
System:
The UNT Digital Library
Clean Energy Manufacturing: U.S. Competitiveness and State Policy Strategies
The capital intensive nature of clean energy technologies suggests that manufacturing clean energy equipment has the potential to support state and local economic development efforts. However, manufacturing siting decisions tend to be complex and multi-variable decision processes that require in-depth knowledge of specific markets, the logistical requirements of a given technology, and insight into global clean tech trends. This presentation highlights the potential of manufacturing in supporting economic development opportunities while also providing examples of the financial considerations affecting manufacturing facility siting decisions for wind turbine blades and solar PV. The presentation also includes discussion of other more qualitative drivers of facility siting decisions as gleaned from NREL industry interviews and discusses strategies state and local policymakers may employee to bolster their chances of successfully attracting clean energy manufacturers to their localities.
Date:
February 1, 2014
Creator:
Lantz, E.
Object Type:
Presentation
System:
The UNT Digital Library