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1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet (open access)

1.1 Simulations of a Free-Electron Laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet

This report is a descriptive summary of the simulation of a free- electron laser Oscillator at Jefferson Lab Lasing in the Vacuum Ultraviolet
Date: April 1, 2013
Creator: Shinn, Michelle D. & Benson, Stephen V.
System: The UNT Digital Library
Assessing the Battery Cost at Which Plug-In Hybrid Medium-Duty Parcel Delivery Vehicles Become Cost-Effective (open access)

Assessing the Battery Cost at Which Plug-In Hybrid Medium-Duty Parcel Delivery Vehicles Become Cost-Effective

The National Renewable Energy Laboratory (NREL) validated diesel-conventional and diesel-hybrid medium-duty parcel delivery vehicle models to evaluate petroleum reductions and cost implications of hybrid and plug-in hybrid diesel variants. The hybrid and plug-in hybrid variants are run on a field data-derived design matrix to analyze the effect of drive cycle, distance, engine downsizing, battery replacements, and battery energy on fuel consumption and lifetime cost. For an array of diesel fuel costs, the battery cost per kilowatt-hour at which the hybridized configuration becomes cost-effective is calculated. This builds on a previous analysis that found the fuel savings from medium duty plug-in hybrids more than offset the vehicles' incremental price under future battery and fuel cost projections, but that they seldom did so under present day cost assumptions in the absence of purchase incentives. The results also highlight the importance of understanding the application's drive cycle specific daily distance and kinetic intensity.
Date: April 1, 2013
Creator: Ramroth, L. A.; Gonder, J. D. & Brooker, A. D.
System: The UNT Digital Library
Characterization of Detector-Grade CdTeSe Crystals (open access)

Characterization of Detector-Grade CdTeSe Crystals

N/A
Date: April 1, 2013
Creator: Camarda, G.; Yang, G.; Bolotnikov, A. E.; Cui, Y.; Hossain, A.; Kim, K. H. et al.
System: The UNT Digital Library
Cleanable and Hardcoat Coatings for Increased Durability of Silvered Polymeric Mirrors (open access)

Cleanable and Hardcoat Coatings for Increased Durability of Silvered Polymeric Mirrors

We have successfully developed coating formulations which significantly increasethe abrasion resistance of mirror films. We have demonstrated manufacturing scale-up of these films to full width andproduction volumes. Implementation of these films in commercial test sites is planned for Q2 2013(Abengoa, Gossamer Space Frames). This slide show outlines the background and objectives of the project, technical approach and results, and key lessons. It also presents the need and opportunity for reduction of costs for CSP and collectors. It also presents an approach for a large aperture parabolic trough collector with reflective film and a high concentration factor, including demonstration and results.
Date: April 1, 2013
Creator: Padiyath, Raghunath
System: The UNT Digital Library
Collaboratives for Wildlife-Wind Turbine Interaction Research: Fostering Multistakeholder Involvement (Poster) (open access)

Collaboratives for Wildlife-Wind Turbine Interaction Research: Fostering Multistakeholder Involvement (Poster)

This poster highlights the various wildlife-wind collaboratives (specific to wildlife-wind turbine interaction research) that currently exist. Examples of collaboratives are included along with contact information, objectives, benefits, and ways to advance the knowledge base.
Date: April 1, 2013
Creator: Sinclair, K.
System: The UNT Digital Library
Correlation of Photoluminescence measurements with the spatial distribution of dislocations in CdZnTe Crystals (open access)

Correlation of Photoluminescence measurements with the spatial distribution of dislocations in CdZnTe Crystals

N/A
Date: April 1, 2013
Creator: G., Yang; Bolotnikov, A.E.; Cui, Y.; Camarda, G.S.; Hossain, A. & Utpal, R., James, R.B.
System: The UNT Digital Library
Dark Matter in 3D (open access)

Dark Matter in 3D

None
Date: April 1, 2013
Creator: Alves, Daniele S.M.; /Fermilab; Hedri, Sonia El; Wacker, Jay G. & /SLAC /Stanford U., ITP
System: The UNT Digital Library
Development of Offshore Wind Recommended Practice for U.S. Waters: Preprint (open access)

Development of Offshore Wind Recommended Practice for U.S. Waters: Preprint

This paper discusses how the American Petroleum Institute oil and gas standards were interfaced with International Electrotechnical Commission and other wind turbine and offshore industry standards to provide guidance for reliable engineering design practices for offshore wind energy systems.
Date: April 1, 2013
Creator: Musial, W. D.; Sheppard, R. E.; Dolan, D. & Naughton, B.
System: The UNT Digital Library
The Electric Drive Advanced Battery (EDAB) Project (open access)

The Electric Drive Advanced Battery (EDAB) Project

As energy storage system (ESS) technology advances
Date: April 1, 2013
Creator: Wishart, Jeff; Carlson, Barney; Chambon, Paul & Tyler
System: The UNT Digital Library
Etch pits in CdZnTe and other CdTe-based Crystals (open access)

Etch pits in CdZnTe and other CdTe-based Crystals

N/A
Date: April 1, 2013
Creator: Hossain, A.; Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Roy, U. N.; Yang, G. et al.
System: The UNT Digital Library
Extended Range Electric Vehicle Driving and Chargi (open access)

Extended Range Electric Vehicle Driving and Chargi

The EV Project is a large-scale plug-in electric v
Date: April 1, 2013
Creator: Smart, John
System: The UNT Digital Library
Fermi LAT Search for Dark Matter in Gamma-Ray Lines and the Inclusive Photon Spectrum (open access)

Fermi LAT Search for Dark Matter in Gamma-Ray Lines and the Inclusive Photon Spectrum

None
Date: April 1, 2013
Creator: Ackermann, M.; Ajello, M.; Albert, A.; Baldini, L.; Barbiellini, G.; Bechtol, K. et al.
System: The UNT Digital Library
From Used Oxide Nuclear Fuel to Rechargeable Batte (open access)

From Used Oxide Nuclear Fuel to Rechargeable Batte

From Used Oxide Nuclear Fuel to Rechargeable Batte
Date: April 1, 2013
Creator: Yu, Jianguo
System: The UNT Digital Library
Impact of Fuel Metal Impurities on the Durability of a Light-Duty Diesel Aftertreatment System (open access)

Impact of Fuel Metal Impurities on the Durability of a Light-Duty Diesel Aftertreatment System

Alkali and alkaline earth metal impurities found in diesel fuels are potential poisons for diesel exhaust catalysts. A set of diesel engine production exhaust systems was aged to 150,000 miles. These exhaust systems included a diesel oxidation catalyst, selective catalytic reduction (SCR) catalyst, and diesel particulate filter (DPF). Four separate exhaust systems were aged, each with a different fuel: ultralow sulfur diesel containing no measureable metals, B20 (a common biodiesel blend) containing sodium, B20 containing potassium, and B20 containing calcium, which were selected to simulate the maximum allowable levels in B100 according to ASTM D6751. Analysis included Federal Test Procedure emissions testing, bench-flow reactor testing of catalyst cores, electron probe microanalysis (EPMA), and measurement of thermo-mechanical properties of the DPFs. EPMA imaging found that the sodium and potassium penetrated into the washcoat, while calcium remained on the surface. Bench-flow reactor experiments were used to measure the standard nitrogen oxide (NOx) conversion, ammonia storage, and ammonia oxidation for each of the aged SCR catalysts. Vehicle emissions tests were conducted with each of the aged catalyst systems using a chassis dynamometer. The vehicle successfully passed the 0.2 gram/mile NOx emission standard with each of the four aged exhaust systems.
Date: April 1, 2013
Creator: Williams, A.; Burton, J.; McCormick, R. L.; Toops, T.; Wereszczak, A. A.; Fox, E. E. et al.
System: The UNT Digital Library
Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range (open access)

Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range

The objective of the study was to assess the impact of Saflex1 S-series Solar Control PVB (polyvinyl butyral) configurations on conventional vehicle fuel economy and electric vehicle (EV) range. The approach included outdoor vehicle thermal soak testing, RadTherm cool-down analysis, and vehicle simulations. Thermal soak tests were conducted at the National Renewable Energy Laboratory's Vehicle Testing and Integration Facility in Golden, Colorado. The test results quantified interior temperature reductions and were used to generate initial conditions for the RadTherm cool-down analysis. The RadTherm model determined the potential reduction in air-conditioning (A/C) capacity, which was used to calculate the A/C load for the vehicle simulations. The vehicle simulation tool identified the potential reduction in fuel consumption or improvement in EV range between a baseline and modified configurations for the city and highway drive cycles. The thermal analysis determined a potential 4.0% reduction in A/C power for the Saflex Solar PVB solar control configuration. The reduction in A/C power improved the vehicle range of EVs and fuel economy of conventional vehicles and plug-in hybrid electric vehicles.
Date: April 1, 2013
Creator: Rugh, J.; Chaney, L.; Venson, T.; Ramroth, L. & Rose, M.
System: The UNT Digital Library
Long-Term Probability Distribution of Wind Turbine Planetary Bearing Loads (Poster) (open access)

Long-Term Probability Distribution of Wind Turbine Planetary Bearing Loads (Poster)

Among the various causes of bearing damage and failure, metal fatigue of the rolling contact surface is the dominant failure mechanism. The fatigue life is associated with the load conditions under which wind turbines operate in the field. Therefore, it is important to understand the long-term distribution of the bearing loads under various environmental conditions. The National Renewable Energy Laboratory's 750-kW Gearbox Reliability Collaborative wind turbine is studied in this work. A decoupled analysis using several computer codes is carried out. The global aero-elastic simulations are performed using HAWC2. The time series of the drivetrain loads and motions from the global dynamic analysis are fed to a drivetrain model in SIMPACK. The time-varying internal pressure distribution along the raceway is obtained analytically. A series of probability distribution functions are then used to fit the long-term statistical distribution at different locations along raceways. The long-term distribution of the bearing raceway loads are estimated under different environmental conditions. Finally, the bearing fatigue lives are calculated.
Date: April 1, 2013
Creator: Jiang, Z.; Xing, Y.; Guo, Y.; Dong, W.; Moan, T. & Gao, Z.
System: The UNT Digital Library
Long-Term Validation of Rapid Impedance Spectrum M (open access)

Long-Term Validation of Rapid Impedance Spectrum M

The objective of this study was to assess the long
Date: April 1, 2013
Creator: Christophersen, Jon P. & Morrison, John L.
System: The UNT Digital Library
Marie Jeanne Riccoboni's Original "Abeille": Gender in Early Modern Journalism (open access)

Marie Jeanne Riccoboni's Original "Abeille": Gender in Early Modern Journalism

Article on Marie Jeanne Riccoboni's original "Abeille" and gender in early modern journalism.
Date: April 2013
Creator: Kaplan, Marijn S.
System: The UNT Digital Library
The Measured Impact of Vehicle Mass on Road Load F (open access)

The Measured Impact of Vehicle Mass on Road Load F

The U.S. Department of Energy’s Office of Energy E
Date: April 1, 2013
Creator: Carlson, Richard Barney; Lohse-Busch, Henning & Jerem
System: The UNT Digital Library
Method to Branch and Bound Large SBO State Spaces (open access)

Method to Branch and Bound Large SBO State Spaces

Traditional Probabilistic Risk Assessment (PRA) me
Date: April 1, 2013
Creator: Tokuhiro, Akira & Hiromoto, Robert
System: The UNT Digital Library
Model Fidelity Study of Dynamic Transient Loads in a Wind Turbine Gearbox: Preprint (open access)

Model Fidelity Study of Dynamic Transient Loads in a Wind Turbine Gearbox: Preprint

Transient events cause high loads in the drivetrain components so measuring and calculating these loads can improve confidence in drivetrain design. This paper studies the Gearbox Reliability Collaborative 750kW wind turbine gearbox response during transient events using a combined experimental and modeling approach. The transient events include emergency shut-downs and start-ups measured during a field testing period in 2009. The drivetrain model is established in the multibody simulation tool Simpack. A detailed study of modeling fidelity required for accurate load prediction is performed and results are compared against measured loads. A high fidelity model that includes shaft and housing flexibility and accurate bearing stiffnesses is important for the higher-speed stage bearing loads. Each of the transient events has different modeling requirements.
Date: April 1, 2013
Creator: Guo, Y.; Keller, J.; Moan, T. & Xing, Y.
System: The UNT Digital Library
NREL Controllable Grid Interface for Testing MW-Scale Wind Turbine Generators (Poster) (open access)

NREL Controllable Grid Interface for Testing MW-Scale Wind Turbine Generators (Poster)

In order to understand the behavior of wind turbines experiencing grid disturbances, it is necessary to perform a series of tests and accurate transient simulation studies. The latest edition of the IEC 61400-21 standard describes methods for such tests that include low voltage ride-through (LVRT), active power set-point control, ramp rate limitations, and reactive power capability tests. The IEC methods are being widely adopted on both national and international levels by wind turbine manufacturers, certification authorities, and utilities. On-site testing of wind turbines might be expensive and time consuming since it requires both test equipment transportation and personnel presence in sometimes remote locations for significant periods of time because such tests need to be conducted at certain wind speed and grid conditions. Changes in turbine control software or design modifications may require redoing of all tests. Significant cost and test-time reduction can be achieved if these tests are conducted in controlled laboratory environments that replicate grid disturbances and simulation of wind turbine interactions with power systems. Such testing capability does not exist in the United States today. An initiative by NREL to design and construct a 7-MVA grid simulator to operate with the existing 2.5 MW and new upcoming 5-MW …
Date: April 1, 2013
Creator: McDade, M.; Gevorgian, V.; Wallen, R. & Erdman, W.
System: The UNT Digital Library
A Program for Optimizing SRF Linac Costs (open access)

A Program for Optimizing SRF Linac Costs

Every well-designed machine goes through the process of cost optimization several times during its design, production and operation. The initial optimizations are done during the early proposal stage of the project when none of the systems have been engineered. When a superconducting radio frequency (SRF) linac is implemented as part of the design, it is often a difficult decision as to the frequency and gradient that will be used. Frequently, such choices are made based on existing designs, which invariably necessitate moderate to substantial modifications so that they can be used in the new accelerator. Thus the fallacy of using existing designs is that they will frequently provide a higher cost machine or a machine with sub-optimal beam physics parameters. This paper describes preliminary results of a new software tool that allows one to vary parameters and understand the effects on the optimized costs of construction plus 10 year operations of an SRF linac, the associated cryogenic facility, and controls, where operations includes the cost of the electrical utilities but not the labor or other costs. It derives from collaborative work done with staff from Accelerator Science and Technology Centre, Daresbury, UK [1] several years ago while they were in …
Date: April 1, 2013
Creator: Powers, Thomas J.
System: The UNT Digital Library
Relating Pore-Scale Uranium Aquatic Speciation to Intermediate-Scale Aquifer Heterogeneity (open access)

Relating Pore-Scale Uranium Aquatic Speciation to Intermediate-Scale Aquifer Heterogeneity

The speciation and transport of uranium (VI) through porous media is highly dependent on solution conditions, the presence of complexing ligands, and the nature of the porous media. The dependency on many variables makes prediction of U transport in bench-scale experiments and in the field difficult. In particular, the identification of colloidal U phases poses a technical challenge. Transport of U in the presence and absence of natural organic matter (Suwannee River humic acid, SRHA) through silica sand and hematite coated silica sand was tested at pH 4 and 5 using static columns, where flow is controlled by gravity and residence time between advective pore volume exchanges can be strictly controlled. The column effluents were characterized by traditional techniques including ICPMS quantification of total [U] and [Fe], TOC analysis of [DOC], and pH analysis, and also by non-traditional techniques: flow field flow fractionation with online ICPMS detection (FlFFF-ICPMS) and specific UV absorbance (SUVA) characterization of effluent fractions. Key results include that the transport of U through the columns was enhanced by pre-equilibration with SRHA, and previously deposited U was remobilized by the addition of SRHA. The advanced techniques yielded important insights on the mechanisms of transport: FlFFF-ICPMS identified a U?SRHA …
Date: April 1, 2013
Creator: Ranville, James
System: The UNT Digital Library