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FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

GROUND WATER MONITORING AND REMEDIATION 1991年第2期11卷 107-120页

作者： OSTENDORF, DW LEACH, LE HINLEIN, ES XIE, YF David W. Ostendorf is an associate professor in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include unconfined aquifer contamination hazardous waste site remediation and analytical modeling of problems in environmental fluid mechanics. Dr. Ostendorf is a registered professional engineer in Massachusetts and a member of the American Geophysical Union American Society of Civil Engineers Soil Science Society of America Water Pollution Control Federation and Association of Environmental Engineering Professors as well as the National Water Well Association. Lowell E. Leach is an environmental engineer with the Robert S. Kerr Environmental Research Laboratory of the U.S. Environmental Protection Agency (RS Kerr Environmental Research Laboratory U.S. EPA P.O. Box 1198 Ada OK74820). Leach received his B.S. ingeological engineering at the University of Oklahoma in 1959 and has been a registered professional engineer in Oklahoma since 1966. With 29 years of experience in field applications of geological engineering he is responsible for developing methodology for sampling ground water and subsurface materials for the Robert S. Kerr Environmental Research Laboratory. Erich S. Hinlein is a research assistant in the Environmental Engineering Program of the Civil Engineering Department at the University of Massachusetts (Civil Engineering Department University of Massachusetts Amherst MA 01003). His research interests include ground water pollution hazardous waste site investigation and transport processes in unconfined aquifers. Hinlein graduated with a B.S. in electrical and computer engineering from the University of Massachusetts at Amherst in May 1985 and entered the Environmental Engineering Master's Degree Program in January 1989. Yuefeng Xie is a postdoctoral research associate in the Environmental Engineering Program of the Civil Engine

Two complementary field sampling methods for the determination of residual aviation gasoline content in the contaminated capillary fringe of a fine, uniform, sandy soil were investigated. The first method featured field extrusion of core barrels into pint-size Mason jars, while the second consisted of laboratory partitioning of intact stainless steel core sleeves. The barrel extrusion procedure involved jar headspace sampling in a nitrogen-filled glove box, which delineated the 0.7m thick residually contaminated interval for subsequent core sleeve withdrawal from adjacent boreholes. Soil samples removed from the Mason jars (in the field) and sleeve segments (in the laboratory) were subjected to methylene chloride extraction and gas chromatographic analysis to compare their aviation gasoline content. The barrel extrusion sampling method yielded a vertical profile with 0.10m resolution over an essentially continuous 5.0m interval from the ground surface to the water table. The sleeve segment alternative yielded a more resolved 0.03m vertical profile over a shorter 0.8m interval through the capillary fringe. The two methods delivered precise estimates of the vertically integrated mass of aviation gasoline at a given horizontal location, and a consistent view of the vertical profile as well. In the latter regard, a 0.2m thick lens of maximum contamination was found in the center of the capillary fringe, where moisture filled all voids smaller than the mean pore size. The maximum peak was resolved by the core sleeve data, but was partially obscured by the barrel extrusion observations, so that replicate barrels or a half-pint Mason jar size should be considered for data supporting vertical transport analyses in the absence of sleeve partitions.

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FULL-WAVE SOLUTION OF DIELECTRIC LOADED WAVE-GUIDES AND SHIELDED MICROSTRIPS UTILIZING FINITE-DIFFERENCE AND THE CONJUGATE-GRADIENT METHOD

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE computer-AIDED engineering 1991年第4期1卷 346-357页

作者： NARAYANAN, V MANELA, M LADE, RK SARKAR, TK Department of Electrical and Computer Engineering Syracuse University Syracuse New York 13244-1240 Viswanathan Narayanan was born in Bangalore India on December 14 1965. He received the BE degree in Electronics and Communications from B.M.S. College of Engineering Bangalore in 1988. He joined the Department of Electrical Engineering at Syracuse University for his graduate studies in 1989 where he is currently a research assistant. His research interests are in microwave measurements numerical electromagnetics and signal processing. Biographies and photos are not available for M. Manela and R. K. Lade. Tapan K. Sarkar (Sf69-M'76-SM'X1) was born in Calcutta. India on August 2 1948. He received the BTech degree from the Indian Institute of Technology Kharagpur India in 1969 the MScE degree from the University of New Brunswick Fredericton Canada in 1971. and the MS and PhD degrees from Syracuse University. Syracuse NY in 1975. From 1975-1976 he was with the TACO Division of the General Instruments Corporation. He was with the Rochester Institute of Technology (Rochester NY) from 1976-1985. He was a Research Fellow at the Gordon Mckay Laboratory Harvard University Cambridge MA from 1977 to 1978. He is now a Professor in the Department of Electrical and Computer Engineering Syracuse University. His current research interests deal with numerical solutions of operator equations arising in electromagnetics and signal processing with application to system design. He obtained one of the “ best solution” awards in May 1977 at the Rome Air Development Center (RADC) Spectral Estimation Workshop. He has authored or coauthored more than 154 journal articles and conference papers and has written chapters in eight books. Dr. Sarkar is a registered professional engineer in the state of New York. He received the Best Paper Award of the IEEE Transactions on Electromagnetic Compatibility in 1979. He was an Associate Editor for feature articles of the lEEE Antennas arid Propagation Sociefy Newsletter and was

Dynamic analysis of waveguide structures containing dielectric and metal strips is presented. The analysis utilizes a finite difference frequency domain procedure to reduce the problem to a symmetric matrix eigenvalue problem. Since the matrix is also sparse, the eigenvalue problem can be solved quickly and efficiently using the conjugate gradient method resulting in considerable savings in computer storage and time. Comparison is made with the analytical solution for the loaded dielectric waveguide case. For the microstrip case, we get both waveguide modes and quasi-TEM modes. The quasi-TEM modes in the limit of zero frequency are checked with the static analysis which also uses finite difference. Some of the quasi-TEM modes are spurious. This article describes their origin and discusses how to eliminate them. Numerical results are presented to illustrate the principles.

关键词： Waveguides

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FACTORS AFFECTING THE ENCROACHMENT OF TUNGSTEN INTO THE SI/SIO2 INTERFACE DURING THE REDUCTION OF TUNGSTEN HEXAFLUORIDE BY SILICON

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JOURNAL OF THE ELECTROCHEMICAL SOCIETY 1990年第11期137卷 3683-3687页

作者： FEINERMAN, AD Microfabrication Applications Laboratory Department of Electrical Engineering and Computer Science University of Illinois Chicago Illinois 60607

The effect of various plasma and wet chemical surface treatments on the encroachment of tungsten into the interface during the selective reduction of by silicon is discussed. A plasma maximizes tungsten encroachment, ... 详细信息

关键词： Semiconducting Silicon

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On the analysis of three symmetrically coupled microstrip lines on anisotropic substrates

On the analysis of three symmetrically coupled microstrip li...

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Antennas and Propagation Society International Symposium

作者： L. Yu B. Rawat Electrical Engineering/Computer Science Department University of Nevada슠Reno Reno NV USA Microwave Applications Research Center Electrical Engineering/Computer Science Department University of Nevada슠Reno Reno NV USA

A system of three symmetrically coupled microstrip lines on an anisotropic substrate is analyzed. The method used is a straightforward approach involving matrix inversion. Numerical results are computed and plotted using a Green's function method for three mode impedances of a three-line microstrip coupler on an anisotropic substrate ( in /sub zeta /=3.4, in /sub eta /=5.12, theta =30 degrees ).< >

关键词： Microstrip Anisotropic magnetoresistance Impedance Dielectric substrates Boundary conditions Conductors Application software Capacitance Transmission line matrix methods Green's function methods

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ON THE PREDICTION OF EQUILIBRIUM STATES IN HOMOGENEOUS TURBULENCE

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JOURNAL OF FLUID MECHANICS 1989年 209卷 591-615页

作者： SPEZIALE, CG MHUIRIS, NM Institute for Computer Applications in Science and Engineering NASA Langley Research Center Hampton VA 23665 USA Present address: Mathematics Department Case Western Reserve University Cleveland OH 44106 USA.

A comparison of several commonly used turbulence models (including the K–ε model and three second-order closures) is made for the test problem of homogeneous turbulent shear flow in a rotating frame. The time evolution of the turbulent kinetic energy and dissipation rate is calculated for these models and comparisons are made with previously published experiments and numerical simulations. Particular emphasis is placed on examining the ability of each model to predict equilibrium states accurately for a range of the parameter Ω/S (the ratio of the rotation rate to the shear rate). It is found that none of the commonly used second-order closure models yield substantially improved predictions for the time evolution of the turbulent kinetic energy and dissipation rate over the somewhat defective results obtained from the simpler K–ε model for the unstable flow regime. There is also a problem with the equilibrium states predicted by the various models. For example, the K–ε model erroneously yields equilibrium states that are independent of Ω/S while the Launder, Reece & Rodi model and the Shih-Lumley model predict a flow relaminarization when Ω/S > 0.39 - a result that is contrary to numerical simulations and linear spectral analyses, which indicate flow instability for at least the range 0 [les ] Ω/S [les ] 0.5. The physical implications of the results obtained from the various turbulence models considered herein are discussed in detail along with proposals to remedy the deficiencies based on a dynamical systems approach.

关键词： Flow of Fluids

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The approximation of density functions for use in queueing theory

The approximation of density functions for use in queueing t...

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IEEE International Conference on Systems, Man and Cybernetics

作者： H. Yang L. Lipsky Department of Computer Science and Engineering and The Taylor L. Booth Center for Computer Applications and Research University of Connecticut USA

A procedure is developed for testing the accuracy of approximations to probability density functions (PDF) in queueing theory. The approximation can be constructed from the derivatives and moments of a given PDF, if they exist. Four subjects are considered which can be used as criteria to judge the goodness of approximations over the entire range of values of the traffic intensity parameter, rho . A detailed example is presented to discuss the effect which different derivatives/moments matching combinations have on the accuracy of the approximations. The exponential factor is used as an optimizing parameter.< >

关键词： Queueing analysis Polynomials Testing Probability density function Traffic control Steady-state computer science computer applications Application software Fault tolerance

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A NEW ELECTROMAGNETIC PROBE FOR SMALL CONCENTRATION CHANGE MEASUREMENTS IN AQUEOUS DIELECTRIC SOLUTIONS

A NEW ELECTROMAGNETIC PROBE FOR SMALL CONCENTRATION CHANGE M...

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2nd International Symposium on Recent Advances in Microwave Technology(ISRAMT’89)

作者： J.M.McKee P.F.Mastin B.P.Johnson Microwave Applications Research Center Electrical Engineering/Computer Science Department University of Nevada Reno RenoNevada 89557

There is a strong demand in industry for real time monitoring of chemical ***- tronic monitoring techniques have the advantage of a fast response time and good tolerance for high temperature and high pressure *** paper reports on the current status of an ongoing research project involving the design of a planar dielectric resonator based chemical species monitoring probe that can be made very small for localized sensing and will enable real time monitoring of concentration changes in a broad range of chemical reaction processes.

关键词： A NEW ELECTROMAGNETIC PROBE FOR SMALL CONCENTRATION CHANGE MEASUREMENTS IN AQUEOUS DIELECTRIC SOLUTIONS

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Numerical electronic device modeling for circuit simulators

Numerical electronic device modeling for circuit simulators

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Midwest Symposium on Circuits and Systems (MWSCAS)

作者： M. Yanilmaz V.W. Eveleigh Department of Electrical Engineering and Computer Science Technological Institute Northwestern University Evanston IL USA CASE (Computer Applications in Software Engineering) Center Syracuse University Syracuse NY USA

Static and dynamic numerical device modeling based on dot product evaluation of multidimensional Bernstein polynomial interpolants to evaluate device operating characteristics is presented as an alternative to analytical modeling and table look-up modeling schemes that have been proposed. The model formulation satisfies the requirements imposed by the algebraic-differential equation solution algorithms of most simulators, namely continuity of the output variables and preservation of the monotonicity and concavity or convexity of the data. It is to be noted, however, that those are necessary but not sufficient conditions. Simulator convergence is improved by treating the intrinsic node charges as state variables and using their variations over iteration steps as an iteration criterion along with the node voltage variation checks. MOSFET is taken as a benchmark device. Experimental results to illustrate the effect of the basic premises of the numerical model on simulation performance are presented.< >

关键词： Numerical models Circuit simulation Multidimensional systems Polynomials Analytical models Equations Sufficient conditions Voltage MOSFET circuits Numerical simulation

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A frequency-domain characterization of interpolation from nonuniformly spaced data

A frequency-domain characterization of interpolation from no...

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IEEE International Symposium on Circuits and Systems (ISCAS)

作者： G. Kakazu D.C. Munson National Center for Supercomputing Applications Coordinated Science Laboratory University of Illinois Urbana IL USA Department of Electrical and Computer Engineering University of Illinois Urbana IL USA

A linear time-varying (LTV) framework for modeling interpolation from nonuniformly spaced samples is described. This LTV model is used to obtain a frequency-domain description of the interpolation process. The frequency-domain characteristics of a number of commonly used interpolators are presented. In addition, this frequency-domain description permits the design of one-dimensional interpolators through the use of two-dimensional digital filter design techniques. A two-dimensional frequency sampling design approach is explored in an attempt to better approximate the ideal interpolator.< >

关键词： Interpolation Frequency Fourier transforms Signal sampling Time varying systems Application software Digital filters Image reconstruction Signal processing Computed tomography

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CLEER - AN AI-SYSTEM DEVELOPED TO ASSIST EQUIPMENT ARRANGEMENTS ON WARSHIPS

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NAVAL ENGINEERS JOURNAL 1989年第3期101卷 127-137页

作者： ZHOU, HH SILVERMAN, BG SIMKOL, J Dr. H. Harry Zhou:is a research professor at the Institute for Artificial Intelligence of The George Washington University. Dr. Zhou received his master's degree and Ph.D. in computer science from Vanderbilt University in 1984 and 1987 respectively. He did his dissertation in the fields of artificial intelligence analogical reasoning and machine learning. His research interests include: classifier systems genetic algorithms learning by analogy inductive learning adaptive expert systems automated knowledge acquisition and adaption. He is also interested in data base design programming languages mental modeling and software engineering. Dr. Barry G. Silverman:is director of the Institute for Artificial Intelligence and a professor at the Engineering Administration Department of The George Washington University. He is also president of IntelliTek Inc. an AI consulting firm. Dr. Silverman received the B.S.E. M.S.E. and Ph.D. degrees from the University of Pennsylvania. He has been a principal developer of four generic AI products as well as eight AI applications. Since 1979 he has written over 100 papers and reports on these AI efforts. Joel Simkol:is a research scientist currently engaged in designing expert system architectures to support electronic warfare vulnerability analyses threat assessments shipboard topside antenna arrangements and C3countermeasures employment. Mr. Simkol's work in applying expert systems technology to electromagnetic interference and to spectrum management has generated increased interest and participation from all branches of government agencies.

This paper describes a modularized AI system being built to help improve electromagnetic compatibility (EMC) among shipboard topside equipment and their associated systems. CLEER is intended to act as an easy to use integrator of existing expert knowledge and pre-existing data bases and large scale analytical models. Due to these interfaces; to the need for portability of the software; and to artificial intelligence related design requirements (such as the need for spatial reasoning, expert data base management, model base management, track-based reasoning, and analogical (similar ship) reasoning) it was realized that traditional expert system shells would be inappropriate, although relatively off-the-shelf AI technology could be incorporated. In the same vein, the rapid prototyping approach to expert system design and knowledge engineering was not pursued in favor of a rigorous systems engineering methodology. The critical design decisions affecting CLEER's development are summarized in this paper along with lessons learned to date all in terms of “how,” “why,” and “when” specific features are being developed.

关键词： Artificial Intelligence

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