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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Using the sequential regression (SER) algorithm for long-term signal processing. [Intrusion detection]

Description: The use of the sequential regression (SER) algorithm (Electron. Lett., 14, 118(1978); 13, 446(1977)) for long-term processing applications is limited by two problems that can occur when an SER predictor has more weights than required to predict the input signal. First, computational difficulties related to updating the autocorrelation matrix inverse could arise, since no unique least-squares solution exists. Second, the predictor strives to remove very low-level components in the input, and hen… more
Date: January 1, 1980
Creator: Soldan, D. L.; Ahmed, N. & Stearns, S. D.
Item Type: Refine your search to only Article
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.
Item Type: Refine your search to only Report
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
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Planar Channeling Radiation From Relativistic Positrons and Electrons in LiF

Description: Channeling radiation has been measured for planar-channeled 54- and 83-MeV positrons and 17-, 31-, and 54-MeV electrons in the ionic crystal LiF. The results are shown to be in reasonable, but not perfect, agreement with the results of many-beam calculations based upon a model of the crystal as an array of isolated Li/sup +/ and F/sup -/ ions.
Date: July 1, 1983
Creator: Berman, B. L.; Datz, S.; Fearick, R. W.; Swent, R. L.; Pantell, R. H.; Park, H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Estimation and Control in HTGR Fuel Rod Fabrication

Description: A control algorithm has been derived for a HTGR Fuel Rod Fabrication Process utilizing the method of Box and Jenkins. The estimator is a Kalman filter and is compared with a Least Square estimator and a standard control chart. The effects of system delays are presented.
Date: January 1, 1980
Creator: Downing, D. J. & Bailey, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design concepts for a pulse power test facility to simulate EMP surges in overhead power lines. Part I. Fast pulse

Description: Objective of the study was to create conceptual designs of high voltage pulsers capable of simulating two types of electromagnetic pulses (EMPs) caused by a high-altitude nuclear burst; the slow rise time magnetohydrodynamic (MHD-EMP) and the fast rise time high-altitude EMP (HEMP). The pulser design was directed towards facilities capable of performing EMP vulnerability testing of components used in the national electric power system.
Date: February 1, 1986
Creator: Ramrus, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The fiftieth anniversary of the first public announcement of the successful test of fission: Proceedings

Description: This report contains comments and discussions on the history of fission. The following people comments and lectures are discussed in this report: Remarks and introduction of Maxine F. Singer; president's message, Maxine F. Singer; introduction of Stephen Joel Trachtenberg; President's message, Stephen Joel Trachtenberg; introduction of Frederick Seitz; lecture: Nuclear Science: Promises and Perceptions, '' Frederick Seitz; introduction of K. Alex Mueller; lecture: High Temperature Ferroelectric… more
Date: January 1, 1989
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The fiftieth anniversary of the first public announcement of the successful test of fission: Proceedings

Description: This report contains comments and discussions on the history of fission. The following people comments and lectures are discussed in this report: Remarks and introduction of Maxine F. Singer; president`s message, Maxine F. Singer; introduction of Stephen Joel Trachtenberg; President`s message, Stephen Joel Trachtenberg; introduction of Frederick Seitz; lecture: ``Nuclear Science: Promises and Perceptions, `` Frederick Seitz; introduction of K. Alex Mueller; lecture: ``High Temperature Ferroelec… more
Date: December 31, 1989
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Materials studies related to the Cu/sub 2/S/ZnCdS heterojunction. First quarter report, March 15, 1980-June 15, 1980

Description: Work over the first quarter was directed toward compositional measurements of Cu/sub 2/S/ZnCdS junctions by AAS and AES, and modelling of the junction based on these measurements. AAS and AES measurements both indicate an accumulation of Zn under the interface. AES profiles indicate Zn and Cd in the Cu/sub 2/S, although AAS indicates concentrations below 5 x 10/sup 19/ cm/sup -3/. A model based on lateral composition variation at the interface is presented. This model can account for some of th… more
Date: July 1980
Creator: Burton, L. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Annual report, July 1981-June 1982

Description: The report consists of brief progress reports describing thirty-five research projects conducted during FY 1981-1982 in the areas of geothermal energy, ocean thermal energy conversion, biomass, wind energy, solar energy, and hydrogen storage. (ACR)
Date: June 1, 1982
Creator: Brown, N. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Vertical axis wind turbine control strategy

Description: Early expensive in automatic operation of the Sandia 17-m vertical axis research wind turbine (VAWT) has demonstrated the need for a systematic study of control algorithms. To this end, a computer model has been developed that uses actual wind time series and turbine performance data to calculate the power produced by the Sandia 17-m VAWT operating in automatic control. The model has been used to investigate the influence of starting algorithms on annual energy production. The results indicate … more
Date: August 1, 1981
Creator: McNerney, G.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aerodynamic interference between two Darrieus wind turbines

Description: The effect of aerodynamic interference on the performance of two curved bladed Darrieus-type vertical axis wind turbines has been calculated using a vortex/lifting line aerodynamic model. The turbines have a tower-to-tower separation distance of 1.5 turbine diameters, with the line of turbine centers varying with respect to the ambient wind direction. The effects of freestream turbulence were neglected. For the cases examined, the calculations showed that the downwind turbine power decrement (1… more
Date: April 1, 1981
Creator: Schatzle, P. R.; Klimas, P. C. & Spahr, H. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computer subroutine for estimating aerodynamic blade loads on Darrieus vertical axis wind turbines. [FORCE code]

Description: An important aspect of structural design of the Darrieus rotor is the determination of aerodynamic blade loads. This report describes a load generator which has been used at Sandia for quasi-static and dynamic rotor analyses. The generator is based on the single streamtube aerodynamic flow model and is constructed as a FORTRAN IV subroutine to facilitate its use in finite element structural models. Input and output characteristics of the subroutine are described and a complete listing is attach… more
Date: November 1, 1980
Creator: Sullivan, W. N. & Leonard, T. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improving the performance of mass-consistent numerical models using optimization techniques

Description: This report describes a technique of using a mass-consistent model to derive wind speeds over a microscale region of complex terrain. A serious limitation in the use of these numerical models is that the calculated wind field is highly sensitive to some input parameters, such as those specifying atmospheric stability. Because accurate values for these parameters are not usually known, confidence in the calculated winds is low. However, values for these parameters can be found by tuning the mode… more
Date: September 1, 1985
Creator: Barnard, J. C.; Wegley, H. L. & Hiester, T. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On-demand production of uniform DT droplets using pulsed electrohydrodynamic spraying. Charged Particle Research Laboratory report No. 1-82

Description: A technique suitable for on-demand production of uniform DT droplets is investigated using pulsed electrohydrodynamic (EHD) spraying. Liquid hydrogen is employed as the working liquid, into which charge is injected using a sharp tungsten needle raised to high voltage. By controlling this high voltage, the amount of charge injection required for disrupting the liquid surface into a smooth liquid jet of desired size is determined. For on-demand production of the liquid jet (which breaks up into u… more
Date: April 1, 1982
Creator: Kim, K. & Gavrilovic, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A network security monitor

Description: The study of security in computer networks is a rapidly growing area of interest because of the proliferation of networks and the paucity of security measures in most current networks. Since most networks consist of a collection of inter-connected local area networks (LANs), this paper concentrates on the security-related issues in a single broadcast LAN such as Ethernet. Specifically, we formalize various possible network attacks and outline methods of detecting them. Our basic strategy is to … more
Date: November 1, 1989
Creator: Heberlein, L. Todd; Dias, Gihan V.; Levitt, Karl N.; Mukherjee, Biswanath; Wood, Jeff & Wolber, David
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Space and surface charge excitation of a slanted dielectric interface between two electrodes

Description: The two-dimensional, electrostatic problem of a planar dielectric interface between two perfectly conducting plates has been solved numerically. The solution allows for an arbitrary interface angle relative to the plates as well as arbitrary distributions of both charge within the volume and surface charge along the interface. The problem is treated by first converting the governing differential equations to a pair of coupled integral equations using Green's function techniques, then solving th… more
Date: September 1, 1982
Creator: Seidel, D.B. & Levinson, C.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Method of Vibrational Control in the Problem of Stabilization of Chemical Reactors. Progress Report, July 1, 1981-June 30, 1982

Description: The results obtained during the second year of the three years study of vibrational control application to the problem of stabilization of chemical reactors are presented. The main objective was the development of a nonlinear approach to analytical and numerical investigation of the properties of chemical reactors with oscillating parameters. This objective was achieved and the following results were obtained. Nonlinear vibrational control theory was applied to two types of chemical reactors, t… more
Date: March 1, 1982
Creator: Meerkov, S.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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