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Evidence for Distinct Components of the Galactic Stellar Halo from 838 RR Lyrae Stars Discovered in the LONEOS-I Survey

Description: We present 838 ab-type RR Lyrae stars from the Lowell Observatory Near Earth Objects Survey Phase I (LONEOS-I). These objects cover 1430 deg{sup 2} and span distances ranging from 3-30kpc from the Galactic Center. Object selection is based on phased, photometric data with 28-50 epochs. We use this large sample to explore the bulk properties of the stellar halo, including the spatial distribution. The period-amplitude distribution of this sample shows that the majority of these RR Lyrae stars resemble Oosterhoff type I, but there is a significant fraction (26%) which have longer periods and appear to be Oosterhoff type II. We find that the radial distributions of these two populations have significantly different profiles ({rho}{sub OoI} {approx} R{sup -2.26{+-}0.07} and {rho}{sub OoII} {approx} R{sup -2.88{+-}0.11}). This suggests that the stellar halo was formed by at least two distinct accretion processes and supports dual-halo models.
Date: February 23, 2007
Creator: Miceli, A; Rest, A; Stubbs, C W; Hawley, S L; Cook, K H; Magnier, E A et al.
Partner: UNT Libraries Government Documents Department

Turbulent Jet Expansion

Description: This report was made to study the velocity distribution in an open, in a partially open, and in a partially expanding jet. The open-jet observations reveal minor systematic discrepancies from Tollmien's theoretical velocity distribution. The shearing-stress distribution for the partially open jet was determined. The value derived for the ratio of mixing distance to jet width was found to be in close agreement with the corresponding value for the open-jet boundary.
Date: March 1936
Creator: Förthmann, E.
Partner: UNT Libraries Government Documents Department

Determining the Velocity Distribution in the Boundary Layer of an Airfoil Fitted With a Rotary Cylinder

Description: In the closer investigation of the results obtained from a wing model with a rotary cylinder mounted in its leading edge (NACA TM's 307 and 354), the velocity distribution in the vicinity of the surface of the model was determined by a hot-wire anemometer. The results confirmed the belief that the rotary cylinder had considerable effect on the air flow, but demonstrated the fact that the direct influence of the cylinder is confined to a very thin layer in immediate proximity to the surface.
Date: May 1927
Creator: Van der Hegge Zijnen, B. G.
Partner: UNT Libraries Government Documents Department

Flow and Drag Formulas for Simple Quadrics

Description: The pressure distribution and resistance found by theory and experiment for simple quadrics fixed in an infinite uniform stream of practically incompressible fluid are calculated. The experimental values pertain to air and some liquids, especially water; the theoretical refer sometimes to perfect, again to viscid fluids. Formulas for the velocity at all points of the flow field are given. Pressure and pressure drag are discussed for a sphere, a round cylinder, the elliptic cylinder, the prolate and oblate spheroid, and the circular disk. The velocity and pressure in an oblique flow are examined.
Date: December 1979
Creator: Zahm, A. F.
Partner: UNT Libraries Government Documents Department

The load distribution due to sideslip on triangular, trapezoidal, and related plan forms in supersonic flow

Description: "Expressions are presented for the load distribution on a representative group of plan forms in sideslip at supersonic speeds. These expressions were obtained by the application of lifting-surface theories based on the linearized equation for compressible flow. Sketches of the load distributions are included" (p. 1).
Date: January 1950
Creator: Jones, Arthur L. & Alksne, Alberta
Partner: UNT Libraries Government Documents Department

Angular distribution of neutrons from a plane surface

Description: From introduction: "This report determines lattice losses by considering the angular distribution of the neutrons emitted from the interior faces of the lattice and the exterior faces of the target. The purpose of this report is to investigate this problem by considering the dimensions of the faces to be large compared to the total mean free path."
Date: 1951
Creator: Harker, Wesley H.
Partner: UNT Libraries Government Documents Department

Contribution to the ideal efficiency of screw propellers

Description: From Summary: "The stipulation of best thrust distribution is applied to the annular elements of the screw propeller with infinitely many blades in frictionless, incompressible flow and an ideal jet propulsion system derived possessing hyperbolic angular velocity distribution along the blade radius and combining the advantage of uniform thrust distribution over the section with minimum slipstream and rotation losses. This system is then compared with a propeller possessing the same angular velocity at all blade elements and the best possible thrust distribution secured by means of an induced efficiency varying uniformly over the radius. Lastly, the case of the lightly loaded propeller also is discussed."
Date: January 1942
Creator: Hoff, Wilhelm
Partner: UNT Libraries Government Documents Department

Effect of air distribution on radial temperature distribution in one-sixth sector of annular turbojet combustor

Description: Report presenting an experimental investigation in a one-sixth sector of an annular turbojet combustor to determine a method of controlling radial exhaust-gas-temperature distribution in a gas-turbine combustion chamber. The adjustment in controlling air was made by ducting the dilution air into the combustion zone in a predetermined manner through hollow radial struts or by modifying the basket-wall open-hole area. Results regarding the temperature distribution, temperature-rise efficiency, total-pressure loss, and altitude operating limits are provided.
Date: April 5, 1950
Creator: Mark, Herman & Zettle, Eugene V.
Partner: UNT Libraries Government Documents Department

Flux Distribution - Converter Reactor

Description: From introduction: "A simplified calculation has been carried out in order to gain some insight into the flux distribution, peak to average power density, efficiency of a catching blanket and the effect of a reflector in the proposed converter reactor."
Date: January 2, 1952
Creator: Cohen, E. Richard, 1922-
Partner: UNT Libraries Government Documents Department

FINAL REPORT - CENTER FOR GRID MODERNIZATION

Description: The objective of the CGM was to develop high-priority grid modernization technologies in advanced sensors, communications, controls and smart systems to enable use of real-time or near real-time information for monitoring, analyzing and managing distribution and transmission grid conditions. The key strategic approach to carry out individual CGM research and development (R&D) projects was through partnerships, primarily with the GridApp™ Consortium utility members.
Date: June 30, 2008
Creator: Markiewicz, Daniel R
Partner: UNT Libraries Government Documents Department

Relationships between walking and percentiles of adiposity inolder and younger men

Description: To assess the relationship of weekly walking distance to percentiles of adiposity in elders (age {ge} 75 years), seniors (55 {le} age <75 years), middle-age men (35 {le} age <55 years), and younger men (18 {le} age <35 years old). Cross-sectional analyses of baseline questionnaires from 7,082 male participants of the National Walkers Health Study. The walkers BMIs were inversely and significantly associated with walking distance (kg/m{sup 2} per km/wk) in elders (slope {+-} SE: -0.032 {+-} 0.008), seniors (-0.045 {+-} 0.005), and middle-aged men (-0.037 {+-} 0.007), as were their waist circumferences (-0.091 {+-} 0.025, -0.045 {+-} 0.005, and -0.091 {+-} 0.015 cm per km/wk, respectively), and these slopes remained significant when adjusted statistically for reported weekly servings of meat, fish, fruit, and alcohol. The declines in BMI associated with walking distance were greater at the higher than lower percentiles of the BMI distribution. Specifically, compared to the decline at the 10th BMI percentile, the decline in BMI at the 90th percentile was 5.1-fold greater in elders, 5.9-fold greater in seniors, and 6.7-fold greater in middle-age men. The declines in waist circumference associated with walking distance were also greater among men with broader waistlines. Exercise-induced weight loss (or self-selection) causes an inverse relationship between adiposity and walking distance in men 35 and older that is substantially greater among fatter men.
Date: June 1, 2005
Creator: Williams, Paul T.
Partner: UNT Libraries Government Documents Department

Evaluation of Instrumentation and Dynamic Thermal Ratings for Overhead Lines

Description: In 2010, a project was initiated through a partnership between the Department of Energy (DOE) and the New York Power Authority (NYPA) to evaluate EPRI's rating technology and instrumentation that can be used to monitor the thermal states of transmission lines and provide the required real-time data for real-time rating calculations. The project included the installation and maintenance of various instruments at three 230 kV line sites in northern New York. The instruments were monitored, and data collection and rating calculations were performed for about a three year period.
Date: January 31, 2013
Creator: Phillips, A.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of NACA RM 10 missile in 8 by 6 foot supersonic wind tunnel at Mach numbers from 1.49 to 1.98. 3: analysis of force distribution at angle of attack (stabilizing fins removed)

Description: Report presenting an analysis of the force distribution on a slender pointed body of revolution at angle of attack utilizing pressure-distribution data and balance measurements. The data were obtained in the supersonic tunnel at a variety of Mach numbers and angles of attack. Results regarding normal forces and axial force are provided.
Date: December 12, 1950
Creator: Luidens, Roger W. & Simon, Paul C.
Partner: UNT Libraries Government Documents Department

Theoretical distribution of lift on thin wings at supersonic speeds (An extension)

Description: Report presenting a derivation of a point-source method based on the linearized theory for obtaining the pressure coefficient on thin wings at supersonic speeds. The analysis is continued to formulate the velocity potential for regions influenced by so-called subsonic trailing edges.
Date: May 1948
Creator: Evvard, John C.
Partner: UNT Libraries Government Documents Department

Use of source distributions for evaluating theoretical aerodynamics of thin finite wings at supersonic speeds

Description: From Summary: "A series of publications on the source-distribution methods for evaluating the aerodynamics of thin wings at supersonic speeds is summarized, extended, and unified. Included in the first part are the deviations of: (a) the linearized partial-differential equation for unsteady flow at a substantially constant Mach number. b) The source-distribution solution for the perturbation-velocity potential that satisfies the boundary conditions of tangential flow at the surface and in the plane of the wing; and (c) the integral equation for determining the strength and the location of sources to describe the interaction effects (as represented by upwash) of the bottom and top wing surfaces through the region between the finite wing boundary and the foremost Mach wave. The second part deals with steady-state thin-wing problems. The third part of the report approximates the integral equation for unsteady upwash and includes a solution of approximate equation. Expressions are then derived to evaluate the load distributions for time-dependent finite-wing motions."
Date: June 17, 1949
Creator: Evvard, John C.
Partner: UNT Libraries Government Documents Department

Dynamic Line Rating Oncor Electric Delivery Smart Grid Program

Description: Electric transmission lines are the lifeline of the electric utility industry, delivering its product from source to consumer. This critical infrastructure is often constrained such that there is inadequate capacity on existing transmission lines to efficiently deliver the power to meet demand in certain areas or to transport energy from high-generation areas to high-consumption regions. When this happens, the cost of the energy rises; more costly sources of power are used to meet the demand or the system operates less reliably. These economic impacts are known as congestion, and they can amount to substantial dollars for any time frame of reference: hour, day or year. There are several solutions to the transmission constraint problem, including: construction of new generation, construction of new transmission facilities, rebuilding and reconductoring of existing transmission assets, and Dynamic Line Rating (DLR). All of these options except DLR are capital intensive, have long lead times and often experience strong public and regulatory opposition. The Smart Grid Demonstration Program (SGDP) project co-funded by the Department of Energy (DOE) and Oncor Electric Delivery Company developed and deployed the most extensive and advanced DLR installation to demonstrate that DLR technology is capable of resolving many transmission capacity constraint problems with a system that is reliable, safe and very cost competitive. The SGDP DLR deployment is the first application of DLR technology to feed transmission line real-time dynamic ratings directly into the system operation’s State Estimator and load dispatch program, which optimizes the matching of generation with load demand on a security, reliability and economic basis. The integrated Dynamic Line Rating (iDLR)1 collects transmission line parameters at remote locations on the lines, calculates the real-time line rating based on the equivalent conductor temperature, ambient temperature and influence of wind and solar radiation on the stringing section, transmits the data to ...
Date: May 4, 2013
Creator: Johnson, Justin; Smith, Cale; Young, Mike; Donohoo, Ken; Owen, Ross; Clark, Eddit et al.
Partner: UNT Libraries Government Documents Department

ElGENANALYSlS OF LARGE ELECTRIC POWER SYSTEMS

Description: Modern electric power systems are large and complicated, and, in many regions, the generation and transmission systems are operating near their limits. Eigenanalysis is one of the tools used to analyze the behavior of these systems. Standard eigenvalue methods require that simplified models be used for these analyses; however, these simplified models do not adequately model all of the characteristics of large power systems. Thus, new eigenanalysis methods that can analyze detailed power system models are required. The primary objectives of the work described in this report were I) to determine the availability of eigenanalysis algorithms that are better than methods currently being applied and that could be used an large power systems and 2) to determine if vector supercomputers could be used to significantly increase the size of power systems that can be analyzed by a standard power system eigenanalysis code. At the request of the Bonneville Power Administration, the Pacific Northwest Laboratory (PNL) conducted a literature review of methods currently used for the eigenanalysis of large electric power systems, as well as of general eigenanalysis algorithms that are applicable to large power systems. PNL found that a number of methods are currently being used for the this purpose, and all seem to work fairly well. Furthermore, most of the general eigenanalysis techniques that are applicable to power systems have been tried on these systems, and most seem to work fairly well. One of these techniques, a variation of the Arnoldi method, has been incorporated into a standard power system eigenanalysis package. Overall, it appears that the general purpose eigenanalysis methods are more versatile than most of the other methods that have been used for power systems eigenanalysis. In addition, they are generally easier to use. For some problems, however, it appears that some of the other eigenanalysis methods ...
Date: February 1, 1991
Creator: Elwood, D. M.
Partner: UNT Libraries Government Documents Department

Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters

Description: Zenergy Power has successfully designed, built, tested, and installed in the US electrical grid a saturable reactor Fault Current Limiter. Beginning in 2007, first as SC Power Systems and from 2008 as Zenergy Power, Inc., ZP used DOE matching grant and ARRA funds to help refine the design of the saturated reactor fault current limiter. ZP ultimately perfected the design of the saturated reactor FCL to the point that ZP could reliably design a suitable FCL for most utility applications. Beginning with a very basic FCL design using 1G HTS for a coil housed in a LN2 cryostat for the DC bias magnet, the technology progressed to a commercial system that was offered for sale internationally. Substantial progress was made in two areas. First, the cryogenics cooling system progressed from a sub-cooled liquid nitrogen container housing the HTS coils to cryostats utilizing dry conduction cooling and reaching temperatures down to less than 20 degrees K. Large, round cryostats with “warm bore” diameters of 1.7 meters enabled the design of large tanks to hold the AC components. Second, the design of the AC part of the FCL was refined from a six legged “spider” design to a more compact and lighter design with better fault current limiting capability. Further refinement of the flux path and core shape led to an efficient saturated reactor design requiring less Ampere-turns to saturate the core. In conclusion, the development of the saturable reactor FCL led to a more efficient design not requiring HTS magnets and their associated peripheral equipment, which yielded a more economical product in line with the electric utility industry expectations. The original goal for the DOE funding of the ZP project “Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters” was to stimulate the HTS wire industry with, first ...
Date: October 31, 2011
Creator: Darmann, Frank; Lombaerde, Robert; Moriconi, Franco & Nelson, Albert
Partner: UNT Libraries Government Documents Department

Pecan Street Smart Grid Extension Service at the University of Texas

Description: Through funding from the Department of Energy’s Electricity Delivery and Reliability Office, Pecan Street Inc., in partnership with Austin Energy and Oncor, developed and tested third- party data access platforms and services for Green Button offerings and for other home energy use data providers. As more utilities seek to offer Green Button-compliant data to their customers, the question continually arises of how this data can be used to help customers better manage their energy use.
Date: November 19, 2013
Creator: McCracken, Brewster
Partner: UNT Libraries Government Documents Department

Smart Grid Integration Laboratory

Description: The initial federal funding for the Colorado State University Smart Grid Integration Laboratory is through a Congressionally Directed Project (CDP), DE-OE0000070 Smart Grid Integration Laboratory. The original program requested in three one-year increments for staff acquisition, curriculum development, and instrumentation – all which will benefit the Laboratory. This report focuses on the initial phase of staff acquisition which was directed and administered by DOE NETL/ West Virginia under Project Officer Tom George. Using this CDP funding, we have developed the leadership and intellectual capacity for the SGIC. This was accomplished by investing (hiring) a core team of Smart Grid Systems engineering faculty focused on education, research, and innovation of a secure and smart grid infrastructure. The Smart Grid Integration Laboratory will be housed with the separately funded Integrid Laboratory as part of CSU’s overall Smart Grid Integration Center (SGIC). The period of performance of this grant was 10/1/2009 to 9/30/2011 which included one no cost extension due to time delays in faculty hiring. The Smart Grid Integration Laboratory’s focus is to build foundations to help graduate and undergraduates acquire systems engineering knowledge; conduct innovative research; and team externally with grid smart organizations. Using the results of the separately funded Smart Grid Workforce Education Workshop (May 2009) sponsored by the City of Fort Collins, Northern Colorado Clean Energy Cluster, Colorado State University Continuing Education, Spirae, and Siemens has been used to guide the hiring of faculty, program curriculum and education plan. This project develops faculty leaders with the intellectual capacity to inspire its students to become leaders that substantially contribute to the development and maintenance of Smart Grid infrastructure through topics such as: (1) Distributed energy systems modeling and control; (2) Energy and power conversion; (3) Simulation of electrical power distribution system that integrates significant quantities of renewable and distributed energy ...
Date: September 30, 2011
Creator: Troxell, Wade
Partner: UNT Libraries Government Documents Department

A new method for multinomial inference using Dempster-Shafer theory

Description: A new method for multinomial inference is proposed by representing the cell probabilities as unordered segments on the unit interval and following Dempster-Shafer (DS) theory. The resulting DS posterior is then strengthened to improve symmetry and learning properties with the final posterior model being characterized by a Dirichlet distribution. In addition to computational simplicity, the new model has desirable invariance properties related to category permutations, refinements, and coarsenings. Furthemore, posterior inference on relative probabilities amongst certain cells depends only on data for the cells in question. Finally, the model is quite flexible with regard to parameterization and the range of testable assertions. Comparisons are made to existing methods and illustrated with two examples.
Date: January 1, 2009
Creator: Lawrence, Earl Christopher; Vander Wiel, Scott; Liu, Chuanhai & Zhang, Jianchun
Partner: UNT Libraries Government Documents Department