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Defense Suppliers: Factors Affecting U.S. Titanium Aircraft Component Manufacturers' Market Share of DOD Business (open access)

Defense Suppliers: Factors Affecting U.S. Titanium Aircraft Component Manufacturers' Market Share of DOD Business

A letter report issued by the Government Accountability Office with an abstract that begins "Census data show that U.S. and foreign produced titanium prices varied from 2003 through 2012 depending on the product. For example, in 2012, the export price (the proxy for the U.S. price) for titanium bar--used to make engine blades--was higher than the import price (the proxy for the foreign price), while the export price for titanium sheet--used to make wing components--was less than the import price. Industry officials noted that these differences may be due to varying operating costs and titanium production capabilities in different countries and to titanium producers' negotiated agreements with prime contractors or aircraft component manufacturers."
Date: July 1, 2013
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Discretionary Spending in the Patient Protection and Affordable Care Act (ACA) (open access)

Discretionary Spending in the Patient Protection and Affordable Care Act (ACA)

None
Date: July 1, 2013
Creator: Redhead, C. Stephen; Lister, Sarah A.; Colello, Kirsten J.; Sarata, Amanda K. & Heisler, Elayne J.
Object Type: Report
System: The UNT Digital Library
Pakistan: U.S. Foreign Assistance (open access)

Pakistan: U.S. Foreign Assistance

None
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library

Performance and Reliability of Interface Materials for Automotive Power Electronics

Thermal management and reliability are important because excessive temperature can degrade the performance, life, and reliability of power electronics and electric motors. Advanced thermal management technologies enable keeping temperature within limits; higher power densities; and lower cost materials, configurations and systems. Thermal interface materials, bonded interface materials and the reliability of bonded interfaces are discussed in this presentation.
Date: July 1, 2013
Creator: Narumanchi, S.; DeVoto, D.; Mihalic, M. & Paret, P.
Object Type: Presentation
System: The UNT Digital Library
Reducing Office Plug Loads through Simple and Inexpensive Advanced Power Strips: Preprint (open access)

Reducing Office Plug Loads through Simple and Inexpensive Advanced Power Strips: Preprint

This paper documents the process (and results) of applying Advanced Power Strips with various control approaches.
Date: July 1, 2013
Creator: Metzger, I.; Sheppy, M. & Cutler, D.
Object Type: Article
System: The UNT Digital Library
Potential Economic Impacts from Offshore Wind in the Southeast Region (Fact Sheet) (open access)

Potential Economic Impacts from Offshore Wind in the Southeast Region (Fact Sheet)

Offshore wind is a clean, renewable source of energy and can be an economic driver in the United States. To better understand the employment opportunities and other potential regional economic impacts from offshore wind development, the U.S. Department of Energy (DOE) funded research that focuses on four regions of the country. The studies use multiple scenarios with various local job and domestic manufacturing content assumptions. Each regional study uses the new offshore wind Jobs and Economic Development Impacts (JEDI) model, developed by the National Renewable Energy Laboratory. This fact sheet summarizes the potential economic impacts identified by the study for the Southeast (defined here as Georgia, South Carolina, North Carolina, and Virginia).
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Constitutive Modeling of High Temperature Uniaxial (open access)

Constitutive Modeling of High Temperature Uniaxial

Inconel Alloy 617 is a high temperature creep and
Date: July 1, 2013
Creator: Pritchard, P.G.; Carroll, L.J. & Hassan, T.
Object Type: Article
System: The UNT Digital Library
Summary of Conclusions and Recommendations Drawn from the DeepCWind Scaled Floating Offshore Wind System Test Campaign: Preprint (open access)

Summary of Conclusions and Recommendations Drawn from the DeepCWind Scaled Floating Offshore Wind System Test Campaign: Preprint

The DeepCwind consortium is a group of universities, national labs, and companies funded under a research initiative by the U.S. Department of Energy (DOE) to support the research and development of floating offshore wind power. The two main objectives of the project are to better understand the complex dynamic behavior of floating offshore wind systems and to create experimental data for use in validating the tools used in modeling these systems. In support of these objectives, the DeepCwind consortium conducted a model test campaign in 2011 of three generic floating wind systems, a tension-leg platform (TLP), a spar-buoy (spar), and a semisubmersible (semi). Each of the three platforms was designed to support a 1/50th-scale model of a 5 MW wind turbine and was tested under a variety of wind/wave conditions. The focus of this paper is to summarize the work done by consortium members in analyzing the data obtained from the test campaign and its use for validating the offshore wind modeling tool, FAST.
Date: July 1, 2013
Creator: Robertson, A. N.; Jonkman, J. M.; Masciola, M. D.; Molta, P.; Goupee, A. J.; Coulling, A. J. et al.
Object Type: Article
System: The UNT Digital Library

Novel Scanning Lens Instrument for Evaluating Fresnel Lens Performance: Equipment Development and Initial Results

A system dedicated to the optical transmittance characterization of Fresnel lenses has been developed at NREL, in collaboration with the UPM. The system quantifies the optical efficiency of the lens by generating a performance map. The shape of the focused spot may also be analyzed to understand change in the lens performance. The primary instrument components (lasers and CCD detector) have been characterized to confirm their capability for performing optical transmittance measurements. Measurements performed on SoG and PMMA lenses subject to a variety of indoor conditions (e.g., UV and damp heat) identified differences in the optical efficiency of the evaluated lenses, demonstrating the ability of the Scanning Lens Instrument (SLI) to distinguish between the aged lenses.
Date: July 1, 2013
Creator: Herrero, R.; Miller, D. C.; Kurtz, S. R.; Anton, I. & Sala, G.
Object Type: Presentation
System: The UNT Digital Library
Intra-membrane molecular interactions of K%2B channel proteins : application to problems in biodefense and bioenergy. (open access)

Intra-membrane molecular interactions of K%2B channel proteins : application to problems in biodefense and bioenergy.

Ion channel proteins regulate complex patterns of cellular electrical activity and ionic signaling. Certain K+ channels play an important role in immunological biodefense mechanisms of adaptive and innate immunity. Most ion channel proteins are oligomeric complexes with the conductive pore located at the central subunit interface. The long-term activity of many K+ channel proteins is dependent on the concentration of extracellular K+; however, the mechanism is unclear. Thus, this project focused on mechanisms underlying structural stability of tetrameric K+ channels. Using KcsA of Streptomyces lividans as a model K+ channel of known structure, the molecular basis of tetramer stability was investigated by: 1. Bioinformatic analysis of the tetramer interface. 2. Effect of two local anesthetics (lidocaine, tetracaine) on tetramer stability. 3. Molecular simulation of drug docking to the ion conduction pore. The results provide new insights regarding the structural stability of K+ channels and its possible role in cell physiology.
Date: July 1, 2013
Creator: Moczydlowski, Edward G.
Object Type: Report
System: The UNT Digital Library
Feasibility Study of Economics and Performance of Solar Photovoltaics at the Santo Domingo Pueblo in Sandoval County, New Mexico (open access)

Feasibility Study of Economics and Performance of Solar Photovoltaics at the Santo Domingo Pueblo in Sandoval County, New Mexico

The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Pueblo of Santo Domingo in Sandoval County, New Mexico, for a renewable energy production feasibility study. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess specific areas on the Pueblo for potential installation of photovoltaic (PV) systems and to estimate the cost, performance, and site impacts of different PV options. The report also recommends financing options that could assist in the implementation of these PV systems.
Date: July 1, 2013
Creator: Geiger, J.; Lisell, L. & Mosey, G.
Object Type: Report
System: The UNT Digital Library
Assessing Fatigue and Ultimate Load Uncertainty in Floating Offshore Wind Turbines Due to Varying Simulation Length (open access)

Assessing Fatigue and Ultimate Load Uncertainty in Floating Offshore Wind Turbines Due to Varying Simulation Length

With the push towards siting wind turbines farther offshore due to higher wind quality and less visibility, floating offshore wind turbines, which can be located in deep water, are becoming an economically attractive option. The International Electrotechnical Commission's (IEC) 61400-3 design standard covers fixed-bottom offshore wind turbines, but there are a number of new research questions that need to be answered to modify these standards so that they are applicable to floating wind turbines. One issue is the appropriate simulation length needed for floating turbines. This paper will discuss the results from a study assessing the impact of simulation length on the ultimate and fatigue loads of the structure, and will address uncertainties associated with changing the simulation length for the analyzed floating platform. Recommendations of required simulation length based on load uncertainty will be made and compared to current simulation length requirements.
Date: July 1, 2013
Creator: Stewart, G.; Lackner, M.; Haid, L.; Matha, D.; Jonkman, J. & Robertson, A.
Object Type: Article
System: The UNT Digital Library
Scale/Analytical Analyses of Freezing and Convective Melting with Internal Heat Generation (open access)

Scale/Analytical Analyses of Freezing and Convective Melting with Internal Heat Generation

Using a scale/analytical analysis approach, we model phase change (melting) for pure materials which generate constant internal heat generation for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. The analysis also consider constant heat flux (in a cylindrical geometry).We show the time scales in which conduction and convection heat transfer dominate.
Date: July 1, 2013
Creator: Siahpush, Ali S.; Crepeau, John & Sabharwall, Piyush
Object Type: Article
System: The UNT Digital Library
INL High Performance Building Strategy (open access)

INL High Performance Building Strategy

High performance buildings, also known as sustaina
Date: July 1, 2013
Creator: Fossum, Ernest & Ischay, Chris
Object Type: Report
System: The UNT Digital Library
Rotation Angle for the Optimum Tracking of One-Axis Trackers (open access)

Rotation Angle for the Optimum Tracking of One-Axis Trackers

An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.
Date: July 1, 2013
Creator: Marion, W. F. & Dobos, A. P.
Object Type: Report
System: The UNT Digital Library
Advanced Energy Retrofit Guide: Practical Ways to Improve Energy Performance; Grocery Stores (Revised) (Book) (open access)

Advanced Energy Retrofit Guide: Practical Ways to Improve Energy Performance; Grocery Stores (Revised) (Book)

The U.S. Department of Energy developed the Advanced Energy Retrofit Guides (AERGs) to provide specific methodologies, information, and guidance to help energy managers and other stakeholders successfully plan and execute energy efficiency improvements. Detailed technical discussion is fairly limited in these guides. Instead, we emphasize actionable information, practical methodologies, diverse case studies, and unbiased evaluations of the most promising retrofit measures for each building type. A series of AERGs is under development, addressing key segments of the commercial building stock. Grocery stores were selected as one of the highest priority sectors, because they represent one of the most energy-intensive market segments.
Date: July 1, 2013
Creator: Hendron, B.
Object Type: Report
System: The UNT Digital Library
Environmental Regulation Impacts on Eastern Interconnection Performance (open access)

Environmental Regulation Impacts on Eastern Interconnection Performance

In the United States, recent environmental regulations will likely result in the removal of nearly 30 GW of oil and coal-fired generation from the power grid, mostly in the Eastern Interconnection (EI). The effects of this transition on voltage stability and transmission line flows have previously not been studied from a system-wide perspective. This report discusses the results of power flow studies designed to simulate the evolution of the EI over the next few years as traditional generation sources are replaced with environmentally friendlier ones such as natural gas and wind.
Date: July 1, 2013
Creator: Markham, Penn N; Liu, Yilu & Young II, Marcus Aaron
Object Type: Report
System: The UNT Digital Library
UNDERSTANDING FLOW OF ENERGY IN BUILDINGS USING MODAL ANALYSIS METHODOLOGY (open access)

UNDERSTANDING FLOW OF ENERGY IN BUILDINGS USING MODAL ANALYSIS METHODOLOGY

It is widely understood that energy storage is the key to integrating variable generators into the grid. It has been proposed that the thermal mass of buildings could be used as a distributed energy storage solution and several researchers are making headway in this problem. However, the inability to easily determine the magnitude of the building’s effective thermal mass, and how the heating ventilation and air conditioning (HVAC) system exchanges thermal energy with it, is a significant challenge to designing systems which utilize this storage mechanism. In this paper we adapt modal analysis methods used in mechanical structures to identify the primary modes of energy transfer among thermal masses in a building. The paper describes the technique using data from an idealized building model. The approach is successfully applied to actual temperature data from a commercial building in downtown Boise, Idaho.
Date: July 1, 2013
Creator: Gardner, John; Heglund, Kevin; Wymelenberg, Kevin Van Den & Rieger, Craig
Object Type: Article
System: The UNT Digital Library

Thermal Performance and Reliability of Bonded Interfaces for Power Electronics Packaging Applications

This presentation discusses the thermal performance and reliability of bonded interfaces for power electronics packaging applications.
Date: July 1, 2013
Creator: Devoto, D.
Object Type: Presentation
System: The UNT Digital Library
Post - Power Energy Densities for LLNL EMB (open access)

Post - Power Energy Densities for LLNL EMB

None
Date: July 1, 2013
Creator: Post, R
Object Type: Report
System: The UNT Digital Library
Improving Heat Recovery In Biomass-Fired Boilers (open access)

Improving Heat Recovery In Biomass-Fired Boilers

None
Date: July 1, 2013
Creator: Keiser, James R.; Sharp, W. B. A.; Singbeil, Douglas; Singh, Preet M.; Frederick, Laurie A. & Meyer, Joseph
Object Type: Report
System: The UNT Digital Library
Enhancing Tribal Energy Security and Clean Energy (Fact Sheet) (open access)

Enhancing Tribal Energy Security and Clean Energy (Fact Sheet)

This fact provides information on the Strategic Technical Assistance Response Team (START) Program, a U.S. Department of Energy Office of Indian Energy Policy and Programs (DOE-IE) initiative to provide technical expertise to support the development of next-generation energy projects in Indian Country.
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Physics with the KLOE-2 experiment at the upgraded DA$PHI$NE (open access)

Physics with the KLOE-2 experiment at the upgraded DA$PHI$NE

None
Date: July 1, 2013
Creator: Amelino-Camelia, G.; Archilli, F.; Babusci, D.; Badoni, D.; Bencivenni, G.; Bernabeu, J. et al.
Object Type: Article
System: The UNT Digital Library
Constitutive Modeling of High Temperature Uniaxial Creep-Fatigue and Creep-Ratcheting Responses of Alloy 617 (open access)

Constitutive Modeling of High Temperature Uniaxial Creep-Fatigue and Creep-Ratcheting Responses of Alloy 617

Inconel Alloy 617 is a high temperature creep and corrosion resistant alloy and is a leading candidate for use in Intermediate Heat Exchangers (IHX) of the Next Generation Nuclear Plants (NGNP). The IHX of the NGNP is expected to experience operating temperatures in the range of 800 degrees - 950 degrees C, which is in the creep regime of Alloy 617. A broad set of uniaxial, low-cycle fatigue, fatigue-creep, ratcheting, and ratcheting-creep experiments are conducted in order to study the fatigue and ratcheting responses, and their interactions with the creep response at high temperatures. A unified constitutive model developed at North Carolina State University is used to simulate these experimental responses. The model is developed based on the Chaboche viscoplastic model framework. It includes cyclic hardening/softening, strain rate dependence, strain range dependence, static and dynamic recovery modeling features. For simulation of the alloy 617 responses, new techniques of model parameter determination are developed for optimized simulations. This paper compares the experimental responses and model simulations for demonstrating the strengths and shortcomings of the model.
Date: July 1, 2013
Creator: Pritchard, P.G.; Carroll, L.J. & Hassan, T.
Object Type: Article
System: The UNT Digital Library