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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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MAGNETOHYDRODYNAMIC SUBMARINE PROPULSION SYSTEMS

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NAVAL ENGINEERS JOURNAL 1991年第3期103卷 141-157页

作者： SWALLOM, DW SADOVNIK, I GIBBS, JS GUROL, H NGUYEN, LV VANDENBERGH, HH Daniel W. Swallomis the director of military power systems at Avco Research Laboratory Inc. a subsidiary of Textron Inc. in Everett Mass. Dr. Swallom received his B.S. M.S. and Ph.D. degrees in mechanical engineering from the University of Iowa Iowa City Iowa in 1969 1970 and 1972 respectively. He has authored numerous papers in the areas of power propulsion and plasma physics and currently is a member of the Aerospace Power Systems Technical Committee of the AIAA. Dr. Swallom has directed various programs for the development of advanced power generation systems lightweight power conditioning systems and advanced propulsion systems for marine applications. His previous experience includes work with Odin International Corporation Maxwell Laboratories Inc. Argonne National Laboratory and the Air Force Aero Propulsion Laboratory. Currently Dr. Swallom is directing the technical efforts to apply magnetohydrodynamic principles to a variety of propulsion and power applications for various marine vehicles and power system requirements respectively. Isaac Sadovnikis a principal research engineer in the Energy Technology Office at Avco Research Laboratory Inc. a subsidiary of Textron Inc. He received his B.S. in engineering (1974) B.S. in physics (1975) M.S. in aeronautics and astronautics (1976) and Ph.D. in physics of fluids (1981) at the Massachusetts Institute of Technology. Dr. Sadovnik has been involved in research work funded by DARPA concerning the use of magnetohydrodynamics for underwater propulsion. He has built theoretical models that predict the hydrodynamic behavior of seawater flow through magnetohydrodynamic ducts and their interaction with the rest of the vehicle (thrust and drag produced). In addition Dr. Sadovnik has been involved in research investigations geared toward the NASP program concerning the use of magnetohydrodynamic combustion-driven accelerator channels. Prior to joining Avco Dr. Sadovnik was a research assistant at MIT where he conducted experimental and

Magnetohydrodynamic propulsion systems for submarines offer several significant advantages over conventional propeller propulsion systems. These advantages include the potential for greater stealth characteristics, increased maneuverability, enhanced survivability, elimination of cavitation limits, greater payload capability, and the addition of a significant emergency propulsion system. These advantages can be obtained with a magnetohydrodynamic propulsion system that is neutrally bouyant and can operate with the existing submarine propulsion system power plant. A thorough investigation of magnetohydrodynamic propulsion systems for submarine applications has been completed. During the investigation, a number of geometric configurations were examined. Each of these configurations and mounting concepts was optimized for maximum performance for a generic attack class submarine. The optimization considered each thruster individually by determining the optimum operating characteristics for each one and accepting only those thrusters that result in a neutrally buoyant propulsion system. The results of this detailed optimization study show that the segmented, annular thruster is the concept with the highest performance levels and greatest efficiency and offers the greatest potential for a practical magnetohydrodynamic propulsion system for attack class submarines. The optimization study results were used to develop a specific point design for a segmented, annular magnetohydrodynamic thruster for an attack class submarine. The design point case has shown that this thruster may be able to provide the necessary thrust to propel an attack class submarine at the required velocity with the potential for a substantial acoustic signature reduction within the constraints of the existing submarine power plant and the maintenance of neutral buoyancy. This innovative magnetohydrodynamic propulsion system offers an approach for submarine propulsion that can be an important contributio

关键词： Ship Propulsion

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Rapid design of testable, high-performance/capacity associative memories 2

Rapid design of testable, high-performance/capacity associat...

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2nd IEEE Symposium on Parallel and Distributed Processing, SPDP 1990

作者： Miller, P.M. Hurson, A.R. Computer Engineering Program Department of Electrical and Computer Engineering Pennsylvania State University University ParkPA16802 United States

ISBN: (纸本)0818620870

VLSI technology has created the opportunity for designers to develop special-purpose application-specific architectures based on associative processing techniques. However the diversity of these applications creates a need for a generalized methodology to quickly produce high-capacity associative chips with different functionalities. The paper introduces such a scheme for designing special-purpose content-addressable memories (CAMs). An overall CAM organization suitable for most special-purpose associative chips is presented and the design, layout, and performance of its modular components is discussed. An example CAM is examined to show the performance and area efficiency of CAMs designed using the proposed scheme. The paper also introduces an improved, highly compact theta -search associative cell. Finally, the testing of CAMs using this organization is discussed. © 1990 IEEE.

关键词： Associative storage

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Phase space topography and the Lyapunov exponent of electrocorticograms in partial seizures

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Brain Topography 1990年第3期2卷 187-201页

作者： Iasemidis, Leonidas D. Chris Sackellares, J. Zaveri, Hitten P. Williams, William J. Bioengineering Program Department of Electrical Engineering and Computer Science United States Epilepsy Program Department of Neurology University of Michigan Ann Arbor 48109-0316 MI 1920 Taubman Center/0316 1500 E. Medical Center Drive United States

Electrocorticograms (ECoG's) from 16 of 68 chronically implanted subdural electrodes, placed over the right temporal cortex in a patient with a right medial temporal focus, were analyzed using methods from nonlinear dynamics. A time series provides information about a large number of pertinent variables, which may be used to explore and characterize the system's dynamics. These variables and their evolution in time produce the phase portrait of the system. The phase spaces for each of 16 electrodes were constructed and from these the largest average Lyapunov exponents (L's), measures of chaoticity of the system (the larger the L, the more chaotic the system is), were estimated over time for every electrode before, in and after the epileptic seizure for three seizures of the same patient. The start of the seizure corresponds to a simultaneous drop in L values obtained at the electrodes nearest the focus. L values for the rest of the electrodes follow. The mean values of L for all electrodes in the postictal state are larger than the ones in the preictal state, denoting a more chaotic state postictally. The lowest values of L occur during the seizure but they are still positive denoting the presence of a chaotic attractor. Based on the procedure for the estimation of L we were able to develop a methodology for detecting prominent spikes in the ECoG. These measures (L^*) calculated over a period of time (10 minutes before to 10 minutes after the seizure outburst) revealed a remarkable coherence of the abrupt transient drops of L^* for the electrodes that showed the inital ictal onset. The L^* values for the electrodes away from the focus exhibited less abrupt transient drops. These results indicate that the largest average Lyapunov exponent L can be useful in seizure detection as well as a discriminatory factor for focus localization in multielectrode analysis. © 1990 Human Sciences Press, Inc.

关键词： chaos ECoG epileptogenic focus localization Lyapunov exponents partial epileptic seizures phase space

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Rapid design of testable, high-performance/capacity associative memories

Rapid design of testable, high-performance/capacity associat...

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International Symposium on Parallel and Distributed Processing (IPDPS)

作者： P.M. Miller A.R. Hurson Computer Engineering Program Department of Electrical and Computer Engineering Pennsylvania State University University Park PA USA

关键词： Testing computer aided manufacturing CADCAM Cams Random access memory Very large scale integration Application software Read-write memory Associative memory Logic

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Use of computer simulation in the development of an algorithm for analysis of paced electrocardiograms

Use of computer simulation in the development of an algorith...

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computers in Cardiology (CinC)

作者： S.E. Greenhut J.M. Jenkins Bioengineering Program and Department of Electrical Engineering and Computer Science University of Michigan Ann Arbor MI USA

A computer model of the interaction between heart and artificial pacemaker is developed which simulates a variety of dual-chamber device responses in the context of 25 possible arrhythmia classes. The heart-pacemaker interaction (HPI) model includes specifications of cardiac, pacemaker, and noise distribution parameters which permit random simulation of pacemaker failure. It simulates random pacemaker output, capture, and sensing malfunctions. The model has been used to train an automated, knowledge-based algorithm designed to analyze paced electrocardiograms for pacemaker function and malfunction. By allowing the straightforward simulation of numerous arrhythmia/pacemaker failure scenarios, the model has significantly reduced the amount of clinical testing and therefore the development time otherwise required.< >

关键词： computer simulation Algorithm design and analysis Pacemakers Electrocardiography Rhythm Heart Computational modeling Context modeling Testing Myocardium

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Effects of aging on polyimide: a study of bulk and interface chemistry

Effects of aging on polyimide: a study of bulk and interface...

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IEEE Workshop on Solid-State Sensor and Actuator

作者： M.C. Buncick D.D. Denton Department of Electrical and Computer Engineering and Materials Science Program University of Wisconsin Madison Madison WI USA

An analysis is presented of polyimides (PIs) exposed to heat and humidity stress over long periods. Electron spectroscopy for chemical analysis (ESCA) and Fourier transform infrared (FTIR) spectroscopy were used to investigate the basic physical mechanisms that affect PI when stressed. The results show that changes are confined to a surface layer at the PI-air interface. ESCA data show significant changes at the PI-air interface and that the PI-Si interface remains unchanged. FTIR transmission data indicate that the bulk chemistry is unaffected by such exposure. The surface chemistry is characterized by a significant reduction in the pyromellitic dyanhydride (PMDA) moiety and changes in the bonding of oxygen. There appear to be changes in the imide structure for the PI surface, but the mechanisms of change require further study. This has reliability implications for microelectronic systems using PI as a dielectric.< >

关键词： Aging Polyimides Spectroscopy Infrared spectra Chemistry Humidity Stress Electrons Chemical analysis Fourier transforms

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computer simulation of heart-pacemaker interaction

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Journal of Electrocardiology 1990年第SUPPL.期23卷 156-156页

作者： Greenhut, Saul E. MacDonald, Robert S. Jenkins, Janice M. Department of Electrical Engineering Computer Science The University of Michigan Ann Arbor MI United States the Bioengineering Program The University of Michigan Ann Arbor MI United States

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A Ray Tracing program For Studying Acoustic Telemetry With Auvs

A Ray Tracing Program For Studying Acoustic Telemetry With A...

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OCEANS

作者： J. McCalla K.C. Baldwin J.D. Irish D.R. Blidberg K. Sivaprasad Ocean Systems Engineering Houston TX USA Ocean Engineering Program University of New Hampshire Durham NH USA Ocean process Analysis Laboratory University of New Hampshire Durham NH USA Marine Systems Engineering Laboratory University of New Hampshire Durham NH USA Electrical and Computer Engineering Department University of New Hampshire Durham NH USA

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