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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 1 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.2 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.3 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 1989.4 Yuefeng Xie is a postdoctoral research associate in the Environmental Engineering Program of the Civil E

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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Expert DB: an assistant database design system 90

Expert DB: an assistant database design system

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Proceedings of the 3rd international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1

作者： A. I. Concepcion R. M. Villafuerte Department of Computer Science Michigan State University Computer Science Graduate Program De La Salle University

ISBN: (纸本)9780897913720

This paper presents an assistant database design system, ExpertDB, which is based on entity-relationship (ER) approach. The approach is to synthesize a normalized ER schema (which consists of entity set and relationship set expressions) from functional dependencies (FD). Using as input the set of attributes and FD's, we derive the minimal cover of FD's, partition and regroup FD's, and finally form the entities and relationship sets. In every aspect of these derivations, ExpertDB provides assistance to the user, which is usually the database administrator (DBA), in the database design. The resulting ER schema is then mapped to relational schema.

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Evaluation of classes of definite integrals involving elementary functions via differentiation of special functions

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Applicable Algebra in Engineering, Communication and Computing 1990年第2期1卷 149-165页

作者： Geddes, K.O. Glasser, M.L. Moore, R.A. Scott, T.C. Department of Computer Science University of Waterloo Waterloo N2L 3G1 Ontario Canada Department of Physics and Department of Mathematics and Computer Science Clarkson University Potsdam 13676 New York United States Guelph-Waterloo Program for Graduate Work in Physics Waterloo Campus United States the Institute for Theoretical Atomic and Molecular Physics at the Harvard-Smithsonian Center for Astrophysics Cambridge 02138 MA 60 Garden Street United States

Herein, it is shown that by exploiting integral definitions of well known special functions, through generalizations and differentiations, broad classes of definite integrals can be solved in closed form or in terms of special functions. This is especially useful when there is no closed form solution to the indefinite form of the integral. In this paper, three such classes of definite integrals are presented. Two of these classes incorporate and supercede all of Kölbig's integration formulae [11], including his formulation for the computation of Cauchy principal values. Also presented are the mathematical derivations that support the implementation of a third class which exploits the incomplete Gamma function. The resulting programs, based on pattern matching, differentiation, and occasionally limits, are very efficient. © 1990 Springer-Verlag.

关键词： Integration MAPLE Special Functions Symbolic Computation

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Real-time robot motion planning using rasterizing computer graphics hardware 90

Real-time robot motion planning using rasterizing computer g...

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Proceedings of the 17th annual conference on computer graphics and interactive techniques

作者： Jed Lengyel Mark Reichert Bruce R. Donald Donald P. Greenberg Graduate Student Program of Computer Graphics Cornell University Ithaca N.Y. Assistant Professor and Director Computer Science Robotics Laboratory Department of Computer Science 4130 Upson HalI Cornell University Ithaca N.Y. Director Program of Computer Graphics Jacob Gould Shurman Professor of Computer Graphics Cornell University Ithaca N.Y.

ISBN: (纸本)9780897913447

We present a real-time robot motion planner that is fast and complete to a resolution. The technique is guaranteed to find a path if one exists at the resolution, and all paths returned are safe. The planner can handle any polyhedral geometry of robot and obstacles, including disjoint and highly concave unions of *** planner uses standard graphics hardware to rasterize configuration space obstacles into a series of bitmap slices, and then uses dynamic programming to create a navigation function (a discrete vector-valued function) and to calculate paths in this rasterized space. The motion paths which the planner produces are minimal with respect to an L1 (Manhattan) distance metric that includes rotation as well as *** examples are shown illustrating the competence of the planner at generating planar rotational and translational plans for complex two and three dimensional robots. Dynamic motion sequences, including complicated and non-obvious backtracking solutions, can be executed in real time.

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PERTURBATIVE SOLUTIONS OF QUANTUM MECHANICAL PROBLEMS BY SYMBOLIC COMPUTATION: A REVIEW

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International Journal of Modern Physics C 1990年第1期1卷 53-76页

作者： T. C. SCOTT R. A. MOORE G. J. FEE M. B. MONAGAN G. LABAHN K. O. GEDDES Guelph-Waterloo Program for Graduate Work in Physics Waterloo Campus Canada Department of Computer Science University of Waterloo Waterloo Ontario N2L-3G1 Canada

It is shown that Symbolic Computation provides excellent tools for solving quantum mechanical problems by perturbation theory. The method presented herein solves for both the eigenfunctions and eigenenergies as power series in the order parameter where each coefficient of the perturbation series is obtained in closed form. The algorithms are expressed in the Maple symbolic computation system but can be implemented on other systems. This approach avoids the use of an infinite basis set and some of the complications of degenerate perturbation theory. It is general and can, in principle, be applied to many separable systems.

关键词： Symbolic computation Maple Quantum mechanics Perturbation theory

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Is American Energy Politics Ideological?

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The Energy Journal 1989年第1期10卷 55 - 76页

作者： Eric M. Uslaner * Department of Government and Politics University of Maryland College Park. Support from the General Research Board of the Graduate School University of Maryland College Park the College of Behavioral and Social Sciences University of Maryland College Park the Computer Science Center of the University of Maryland College Park and the Everett McKinley Dirksen Congressional Leadership Research Center is greatly appreciated as are the comments of John E. Chubb M. Margaret Conway Pietro Nivola Karol Sollan Charles Stewart III Peter Van Doren and the editor and anonymous reviews of this journal. I also appreciate the research assistance of Rodger Payne. Kevin Ogrady provided assistance on the unfolding program while Mike Wagner was (as always) more than invaluable. I am particularly indebted to the representatives of energy interest groups who kindly gave of their time for my interviewing. This paper draws from and expands upon Uslaner (1989 ch. 5).

When we think of energy issues, we generally conjure up ideas of conflicts between producers and consumers. These translate into visions of grand ideological conflicts between the left and the right. Wildavsky and Tennenbaum (1981) speak of battles between "preservationists" and "industrialists." Kalt (1981) argues that "[tihe domestic energy 'crisis' is, far more than anything else, a quarrel over income distribution." Ideological straight fights are marked by a single dimension of conflict. In particular, ideological politics, as opposed to religious or ethnic cleavages, suggests a battle between left and right--or, producers and consumers in the case of energy battles. When there are only two contestants, one is sure to win if the group decision is made by majority rule. Even in the United States Congress, where complex rules often frustrate coherent policy formation, strongly-held positions can prevail over obstructionists if they are determined enough. Yet, during the 1970s many attempts to form a "national energy policy" failed. In the 1980s Congress again stumbled in making natural gas policy as it defeated both decontrol and recontrol proposals.

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Heuristic assignments of redundant software versions and processors in fault-tolerant computer systems for maximum reliability

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Probability in the Engineering and Informational sciences 1987年第4期1卷 457-479页

作者： Kar Leow, Soo Mcallister, David F. Graduate Program in Operations Research North Carolina State University RaleighNC27695 United States Department of Computer Science North Carolina State University RaleighNC27695 United States

We address the problem of assigning multiple copies of n independently developed versions of a program to a set of m(m > n) possibly heterogeneous processors to maximize system reliability. This problem is viewed as a partition and assignment problem. We first partition the set of processors into n clusters or subgroups. A program version is then assigned to be executed on all the processors in the cluster. This means that each processor in the cluster will execute a copy of the assigned version. The cluster's unreliability is the probability of failure of all its processors. Component i of this system is composed of the copies of version i and the assigned cluster of processors. Copyright © Cambridge University Press 1987.

关键词： Combinatorial optimization

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A MATHEMATICAL APPROACH TO THE MANAGEMENT OF SERVICE REQUIREMENTS 11

A MATHEMATICAL APPROACH TO THE MANAGEMENT OF SERVICE REQUIRE...

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11th International computer Measurement Group Conference, CMG 1985

作者： Orchard, Robert A. Department of Computer Science Graduate Program College of Staten Island City University of New York United States

A methodology for the rigorous management of service (performance) requirements on a computer system is introduced utilizing statistical theory. Random sampling techniques coupled with non-parametric probability inequalities are introduced as the major tool for use by the performance manager (analyst) in reporting and controlling the performance of a computer system. From the manager's perspective, the mean response time and the standard deviation of the response time are the only two parameters of processed workload of interest in this approach. Copyright © 1985, Applied computer Research.

关键词： Sampling

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The delivery of education using current technology (panel session) 85

The delivery of education using current technology (panel se...

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Proceedings of the 1985 ACM annual conference on The range of computing : mid-80's perspective: mid-80's perspective

作者： Kenneth L. Krause William E. Ayen David R. Holmes Robert A. Barden Alfred Bork Computer Science Department United States Air Force Academy United States Air Force Academy Graduate Program in Higher Education The University of Vermont Interactive Networks Inc. Information and Computer Science University of California Irvine

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