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Advanced Processing of CdTe- and CuInxGa1-xSe2-Based Solar Cells: Final Report: 18 April 1995 - 31 May 1998

Description: This report summarizes work performed by the University of South Florida Department of Electrical Engineering under this subcontract. The Cadmium telluride(CdTe) portion of this project deals with the development of high-efficiency thin-filmed CdTe solar cells using fabrication techniques that are suitable for manufacturing environments.
Date: January 13, 1999
Creator: Morel, D. L.; Ferekides, C. S.; Bhatt, R.; Jayapalan, A.; Komin, V.; Lin, H. et al.
Partner: UNT Libraries Government Documents Department
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Input Impedance of a Probe Antenna Exciting a TEM Cell

Description: Abstract: The input impedance of a probe antenna exciting a transverse electromagnetic (TEM) transmission line cell is formulated by a variational approach. The formulation also utilizes the results from a previous work on the field distribution inside a TEM cell excited by a vertical electrical Hertzian dipole. The final result of imoedance is shown to consist of two distinct terms, which are respectively contributed by the ordinary rectangular waveguide and the gap perturbation. Numerical res… more
Date: April 1982
Creator: Wilson, Perry F.; Chang, David C. & Ma, Mark T.
Partner: UNT Libraries Government Documents Department
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Framework for Design Validation of Security Architectures

Description: This technical report discusses a framework for design validation of security architectures.
Date: November 17, 2008
Creator: Dwoskin, Jeffrey Scott, 1980-; Gomathisankaran, Mahadevan & Lee, Ruby Bei-Loh
Partner: UNT College of Engineering
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Precise Admittance of a Monopole.

Description: The purpose of this paper is to obtain the admittance of a monopole antenna to a higher degree of accuracy than has heretofore been reported in the literature. The model selected for analysis consists of a base-driven monopole of arbitrary dimensions (length and radius) protruding perpendicularly from an infinite ground plane. The transmission line providing the excitation is a coaxial cable with outer sheath truncated at ground level. The problem is solved by obtaining the admittance of the mo… more
Date: August 30, 1968
Creator: Chang, D. C. & Harrison, C. W., Jr.
Partner: UNT Libraries Government Documents Department
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PICASSO: A GENERAL INTERACTIVE GRAPHICS MODELING PROGRAM.

Description: This report is intended to serve as a user's manual for PICASSO. The detailed description of the concepts involved and the methods used in implementing those concepts will be treated in a subsequent paper and are incorporated in the Ph.D. thesis of one of the authors. The program evolved from earlier work on a graphics program for printed circuit board design which had a fixed library of elements. The need for a dynamic graphics program (i.e., one which allows the creation of new elements as re… more
Date: January 1, 1972
Creator: Austin, D.M. & Holmes, H.H.
Partner: UNT Libraries Government Documents Department
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Very high efficiency photovoltaic cells based on fully organic multiple quantum wells. Quarterly technical progress report, 15 February 1995--15 May 1995

Description: The principal project objective is to demonstrate relatively high solar conversion efficiency using extremely low-cost, thin-film technology based on crystalline organic multiple quantum well (MQW) photovoltaic cells. The authors base their work on recent observations both in the laboratory and elsewhere that have indicated the quantum efficiency of organic photoconductors based on vacuum-deposited thin films can be increased by at least two orders of magnitude (to at least 10%) if the organic … more
Date: March 1, 1997
Creator: Forrest, S.R.
Partner: UNT Libraries Government Documents Department
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Visually guided control systems: A new generation of system analysis and design

Description: The main emphasis of the proposal had been to study control systems for which the observation function is perspective. Since a CCD camera observes points upto a perspective projection, it is hoped that these dynamical systems would be useful in the study of visually guided control systems: systems for which the feedback control is to be generated with the aid of a CCD camera. We basically divided our task into three distinct subproblems. (1) To define a perspective dynamical system and study pr… more
Date: April 4, 1994
Creator: Ghosh, B. K.
Partner: UNT Libraries Government Documents Department
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New insights into input relegation control for inverse kinematics of a redundant manipulator. Part 2, The optimization of a secondary criteria involving self motion of the joints

Description: The input relegation control (IRC) technique for redundancy resolution is extended to solve the problem of optimizing a scalar performance criteria representing a secondary objective to be accomplished via self motion of the joints. The criteria is defined to be the error between the vector of joint velocities and a new vector of ``corrective` joint velocities, which is minimized in a Eudidean norm sense. The corrective velocities represent a `corrective` action to be applied to the system and … more
Date: July 1, 1995
Creator: Unseren, M.A.
Partner: UNT Libraries Government Documents Department
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New insights into input relegation control for inverse kinematics of a redundant manipulator. Part 1, On the orthogonality of matrices B and J and comparison to the extended Jacobian method

Description: A method for kinematically modeling a constrained rigid body mechanical system and a method for controlling such a system termed input relegation control (IRC) were applied to resolve the kinematic redundancy of a serial link manipulator moving in an open chain configuration in. A set of equations was introduced to define a new vector variable parameterizing the redundant degrees of freedom (DOF) as a linear function of the joint velocities. The new set was combined with the classical kinematic… more
Date: July 1, 1995
Creator: Unseren, M.A. & Reister, D.B.
Partner: UNT Libraries Government Documents Department
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Stability and heat transfer in time-modulated flows

Description: In May 1991, DOE awarded grant DE-FG02-91ER14179 for the investigation of stability and heat transfer in time-modulated flows. The general objectives of the research being: (1) to demonstrate and quantify theoretically and experimentally the physics of modulational instability; (2) to exhibit experimentally and describe theoretically the sensitivity of modulational instability to harmonic content of the basic state; (3) to model the influence of mean-flow on modulational instability: (4) to exa… more
Date: January 1, 1991
Creator: Thompson, C.
Partner: UNT Libraries Government Documents Department
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Stability and heat transfer in time-modulated flows. Technical progress report, May--October 1991

Description: In May 1991, DOE awarded grant DE-FG02-91ER14179 for the investigation of stability and heat transfer in time-modulated flows. The general objectives of the research being: (1) to demonstrate and quantify theoretically and experimentally the physics of modulational instability; (2) to exhibit experimentally and describe theoretically the sensitivity of modulational instability to harmonic content of the basic state; (3) to model the influence of mean-flow on modulational instability: (4) to exa… more
Date: December 31, 1991
Creator: Thompson, C.
Partner: UNT Libraries Government Documents Department
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The Composite OLAP-Object Data Model

Description: In this paper, we define an OLAP-Object model that combines the main characteristics of OLAP and Object data models in order to achieve their functionalities in a common framework. We classify three different object classes: primitive, regular and composite. Then, we define a query language which uses the path concept in order to facilitate data navigation and data manipulation. The main feature of the proposed language is an anchor. It allows us to fix dynamically an object class (primitive, r… more
Date: December 7, 2005
Creator: Pourabbas, Elaheh & Shoshani, Arie
Partner: UNT Libraries Government Documents Department
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Design concepts for a pulse power test facility to simulate EMP surges. Part II. Slow pulses

Description: The work described in this report was sponsored by the Division of Electric Energy Systems (EES) of the US Department of Energy (DOE) through a subcontract with the Power Systems Technology Program at the Oak Ridge National Laboratory (ORNL). The work deals with the effect of high altitude nuclear bursts on electric power systems. In addition to fast voltage transients, slow, quasi-dc currents are also induced into extended power systems with grounded neutral connections. Similar phenomena at l… more
Date: October 1, 1985
Creator: Dethlefsen, R.
Partner: UNT Libraries Government Documents Department
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Electron cyclotron heating in tokamaks

Description: Tokamaks may be efficiently heated at electron cyclotron resonance by launching of the extraordinary wave from the inside of the torus with a simple waveguide aperture. For typical tokamak parameters, 90% of the incident energy is absorbed in one traversal of the resonant surface. There is an effective maximum density for linear heating at the point where the plasma frequency is equal to the cyclotron frequency. The bulk of the plasma electrons is heated, increasing the perpendicular energy wit… more
Date: November 1, 1977
Creator: Eldridge, O.; Namkung, W. & England, A. C.
Partner: UNT Libraries Government Documents Department
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Workshop on Artificial Superlattices. October 30-31, 1980 at University of Illinois, Urbana-Champaign, Illinois, USA

Description: The program and 24 abstracts are given. The abstracts are divided into the following categories: structure and elastic properties, transport and electronic properties, magnetism and superconductivity, and phonons. The engineering of novel materials using sophisticated preparation techniques has received considerable attention in recent years. This interest has been mainly stimulated by recent developments in preparation techniques such as Molecular Beam Epitaxy, Thermal Vapor Deposition and Spu… more
Date: October 1980
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department
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SIMS three year study on statistics and environmental factors in health. Technical progress report No. 1. [Hazards of air pollution]

Description: Progress is reported for the activities of the Siam Institute for mathematics and society (SIMS), Columbia University, and Stanford University. The SIMS report is concerned with the use of animal experiments in establishing tolerance limits for human exposure to environmental toxicants; valid assessment of the health consequences of occupational and other specialized toxic exposures; mathematical theories for the kinetics of carcinogenesis; data coding, storage, access, and analysis, relationsh… more
Date: December 1, 1976
Partner: UNT Libraries Government Documents Department
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Preliminary evaluation of the University of South Florida Mobile Data Acquisition System, the Idaho National Engineering Laboratory Versatile Data Acquisition System, and the Autologger Vehicle User Survey System produced by Instrumental Solutions of Ottawa, Canada for the Site Operator Program Field Data Collection

Description: The Electric Vehicle (EV) Site Operator Program, is currently composed of thirteen Site Operators. In addition to operating electric vehicles for demonstration of the technology, the Site Operators also perform operational field testing. Data collected by the programs are input to the Site Operator Database at each site and transmitted, periodically, to the database at the INEL. As the program has expanded, some Site Operators have begun operating vehicles at sites remote from their offices. Wi… more
Date: September 1, 1993
Creator: Kiser, D. M. & Richardson, R. A.
Partner: UNT Libraries Government Documents Department
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The potential for microtechnology applications in energy systems: Results of an experts workshop

Description: Microscale technologies, or microelectromechanical systems (MEMS), are currently under development in the United States and abroad. Examples include microsensors, microactuators (including micromotors), and microscale heat exchangers. Typically, microscale devices have features ranging in size from a few microns to several millimeters, with fabrication methods adapted from those developed for the semiconductor industry. Microtechnologies are already being commercialized; initial markets include… more
Date: February 1, 1995
Partner: UNT Libraries Government Documents Department
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Solid hydrogen pellet injection into the ORMAK Tokamak

Description: Solid hydrogen spheres were injected into the ORMAK tokamak as a test of pellet refueling for tokamak fusion reactors. Pellets 70 ..mu..m and 210 ..mu..m in diameter were injected with speeds of 91 m/sec and 100 m/sec, respectively. Each of the 210-..mu..m pellets added about 1% to the number of particles contained in the plasma. Excited neutrals, ablated from these hydrogen spheres, emitted light which was monitored either by a photomultiplier or by a high speed framing camera. From these ligh… more
Date: June 1, 1977
Creator: Foster, C. A.; Colchin, R. J.; Milora, S. L.; Kim, K. & Turnbull, R. J.
Partner: UNT Libraries Government Documents Department
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Miniature Nuclear Magnetic Resonance Spectrometer For In-Situ And In-Process Analysis And Monitoring

Description: The main purpose of this research is to develop a nuclear magnetic resonance (NMR) spectrometer that is small enough to be held in the palm of a hand. Such an instrument could be used in many applications of importance to DOE as well as to industry. These applications would include in-field characterization of contaminants, monitoring and analysis of chemical processes in chemical plants and other environmental monitoring applications. In addition to having drastically reduced size and cost, a … more
Date: June 1, 1999
Creator: Friemand, Gennady & Feinerman, Alan
Partner: UNT Libraries Government Documents Department
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CIBS Solar Cell Development

Description: This research focused on efforts to prepare and characterize the first copper-indium-boron-diselenide (CIBS) photovoltaic materials. Attempts to fabricate CIBS in thin-film form followed a three-step process: 1) RF sputtering of copper, indium, and boron to form a copper-indium-boron (CIB) alloy; 2) ex-situ selenization of CIB via physical vapor deposition; 3) annealing the final product. No CIBS materials were produced with this method due to the formation of an unstable boron diselenide speci… more
Date: October 6, 2008
Creator: Exstrom, Christopher L.
Partner: UNT Libraries Government Documents Department
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