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ACOUSTIC TRANSMISSION OF THE RESPIRATORY SYSTEM USING SPEECH STIMULATION

IEEE TRANSACTIONS ON BIOMEDICAL engineering 1991年第2期38卷 126-132页

作者： COHEN, A BERSTEIN, AD Department of Electrical and Computer Engineering Biomedical Engineering Program Ben-Gurion University of the Negev Beersheba Israel

Two methods for the analysis of the acoustic transmission of the respiratory system are presented. Continuous speech utterance is used as acoustic stimulation. The transmitted acoustic signal is recorded from various sites over the chest wall. The AR method analyzes the power spectral density function of the transmitted sound, which heavily depends on the microphone assembly and the utterance. The method was applied to a screening problem and was tested on a small database that consisted of 19 normal and five abnormal patients. Using the first five AR coefficients and the prediction error of an AR(10) model, as discriminating features, the system screened all abnormals. An ARMA method is suggested, which eliminates the dependence on microphone and utterance. In this method, the generalized least squares identification algorithm is used to estimate the ARMA transfer function of the respiratory system. The normal transfer function demonstrates a peak at the range of 130-250 Hz and sharp decrease in gain for higher frequencies. A pulmonary fibrotic patient demonstrated a peak at the same frequency range, a much higher gain in the high frequency range with an additional peak at about 700 Hz.

关键词： Microphone Device Component Error of prediction frequency ranges Respiratory System Thoracic Wall power spectral density function TRANSFER FUNCTIONS sound transmission

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CHARACTERISTICS OF JUNCTIONS MADE BETWEEN PB AND BI2SR2CACU2O8+X

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IEEE TRANSACTIONS ON MAGNETICS 1991年第2期27卷 935-938页

作者： YANG, YF NORDMAN, JE Materials Science Program Department of Electrical and Computer Engineering University of Wisconsin Madison Madison WI USA

Investigations on the junctions made between Pb and polycrystalline Bi2Sr2CaCu2O8+x (BSCCO) are reported. The BSCCO surfaces were treated with number of methods including mechanically scraping, plasma sputtering, plasma oxidation, and Br etch before junctions were fabricated. The current-voltage characteristics and dynamic resistance (dV/dI) vs voltage have been measured at both 77K and 4.2K. We observed, among other features, a Pb gap structure similar to that seen in Pb/YBa2Cu3O7-delta junctions, a magnetic dependent supercurrent, an asymmetric I-V curve, and narrow resistance peaks. Properties of junctions prepared in different manners are compared. Both XPS and electrical studies indicated that Br etch is not suitable for the BiSrCaCuO system in spite of its successful application in YBa2Cu3O7-delta.

关键词： Plasma measurements Bismuth compounds Plasma applications Plasma properties Strontium Surface resistance Surface treatment Sputtering Oxidation Sputter etching

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SIMPLE APPROACH TO REFLECTANCE ANALYSIS OF BIREFRINGENT STRATIFIED FILMS

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APPLIED OPTICS 1991年第28期30卷 4017-4018页

作者： KNOESEN, A []The author is with the Department of Electrical Engineering Computer Science Organized Research Program on Polymeric Ultrathin Film Systems University of California Davis Davis California 95616

A simple analysis is presented of reflectance from a stratified uniaxial media with the optic axes parallel or perpendicular to the plane of incidence.

关键词： UNIAXIAL FILMS POLED POLYMERS THIN FILM BIREFRINGENT

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An approach to blind equalization of non-minimum phase systems

An approach to blind equalization of non-minimum phase syste...

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International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： W.A. Sethares R.A. Kennedy Z. Gu Department of Electrical and Computer Engineering University of Wisconsin Madison WI USA Department of System Engineering RSPhysSE and Interdisciplinary Engineering Program Faculty of Science Australian National University Canberra ACT Australia

Blind equalization of systems which contain a nonminimum phase component is a difficult task. Minimizing the energy (l/sub 2/ minimization) of the equalizer output (under a fixed tap constraint) cannot be guaranteed to open the eye (to reliably unscramble the message) because it tends to converge to an equalizer setting that contains a reflection of the unstable zeros inside the unit circle. It is shown that, in at least one simple setup involving a mixture of minimum and nonminimum phase elements, an l/sub infinity / minimization of the equalizer output is the appropriate criterion which should be minimized in order to successfully open the eye. Utilizing a finite impulse response equalizer constrained to have a unity coefficient on the center tap, it is shown that for a large enough dimension (depending on the closeness of the zeros of the channel to the unit circle) the eye will be opened. There is no simple (gradient) scheme to exactly implement the l/sub infinity / minimization. The use of a gradient l/sub p/ scheme for large p is proposed.< >

关键词： Blind equalizers Finite impulse response filter Australia Council Information science Predistortion Distortion Cellular neural networks Quadrature amplitude modulation Stability

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Performance analysis of network and database transactions in a CIM system

Performance analysis of network and database transactions in...

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IEEE International Conference on Robotics and Automation (ICRA)

作者： J.S. Joshi A.A. Desrochers CIM Program Digital Equipment Corporation Troy NY USA Electrical Computer and Systems Engineering Department Rensselaer Polytechnic Institute Troy NY USA

A Petri-net-based integrated model for the performance analysis of network and database transactions, generated by manufacturing clients for the computer resources, which are acting as the servers, is discussed. A Petri-net-based multifaceted integrated modeling (PNBMIM) approach to investigate the relevant system integration issues between the logical and the physical access of the information in the manufacturing system is described. The PNBMIM approach proposes an integrated conceptual framework for modeling and performance (both structural and behavioral) analysis of data flow and communication flow. This framework should provide some answers to the impact of relative time-scales on the coupling and decoupling of the various levels of a computer integrated manufacturing (CIM) system and identify the time-scales where integration becomes important.< >

关键词： Performance analysis Transaction databases Intelligent networks computer integrated manufacturing computer aided manufacturing computer networks Data analysis Network topology Petri nets Virtual manufacturing

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Effects of aging on polyimide: a model for dielectric behavior (of relative humidity sensors)

Effects of aging on polyimide: a model for dielectric behavi...

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International Conference on Solid State Sensors and Actuators (TRANSDUCERS)

作者： A.R.K. Ralston M.C. Buncick D.D. Denton T.E. Boltshauser J.M. Funk H.P. Baltes Department of Electrical and Computer Engineering and Materials Science Program University of Wisconsin Madison Madison WI USA Physical Electronics Laboratory Swiss Federal Institute of Technology Zurich Switzerland

Quantifying the effect of moisture on the electrical properties of thin dielectric films requires the use of a model that takes into account the geometry of the test structure and the dielectric properties of the air layer above the device. Using this approach, it was found that the electrical properties of dry PI (polyimide) do not change substantially after six weeks of aging at 85 degrees C/85% RH (relative humidity). The dielectric permittivity of PI as a function of %RH increased with aging for excitation frequencies between 12 Hz and 100 kHz. This increase is correlated with observed changes in the surface chemistry of the aged PI film. Shifts in ESCA peak intensities indicate oxidation of the PI surface and deimidization with aging. Possible mechanisms for the observed changes in dielectric properties with aging include a change in the morphology of the bulk PI, resulting in a decreased surface to volume ratio, increased water absorption, a change in the interaction of absorbed water with the PI matrix, and dielectric interfacial effects.< >

关键词： Aging Polyimides Surface morphology Water Moisture Dielectric films Solid modeling Geometry Testing Dielectric devices

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FIELD SAMPLING OF RESIDUAL AVIATION GASOLINE IN SANDY SOIL

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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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SMALL SHIPS, ADVANCED TECHNOLOGY AND WARFIGHTING PERFORMANCE

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NAVAL ENGINEERS JOURNAL 1991年第3期103卷 30-45页

作者： SKOLNICK, DH SKOLNICK, A David H. Skolnickhas practiced naval engineering in both government and industry. He has supported the Military Sealift Command and the Naval Sea Systems Command Ship Design Group and Amphibious Ship Acquisition Program Office participating in the design and assessment of ship structure evaluation of intact and damaged stability and arrangements during design and construction phases of acquisition conversion and overhaul. He is currently involved in systems engineering and integration. Recent responsibilities have included requirements analyses and feasibility studies interface analyses and computer aided analyses. He received his B.S. in naval architecture and marine engineering from Webb Institute of Naval Architecture in 1982 (as an ASNE scholar) and is currently an M.S. candidate in systems engineering at the University of Virginia. Alfred Skolnickserved over 30 years as an engineering duty officer and retired from the Navy with the rank of captain in 1983. His early assignments included tactical missile engineering shipboard duty and Polaris submarine inertial navigation. He later served in the Deep Submergence Systems Project was project director surface effect ships (SES) David Taylor Model Basin director of technology Joint Navy-Commerce SES Program director combat systems Naval Sea Systems Command and project manager directed energy weapons. His awards include the Navy League's Parsons Award in 1979 for scientific and technical progress ASNE's Gold Medal in 1981 for high energy laser development the Navy Legion of Merit in 1983 National Capital Engineer of the Year in 1986 and the American Defense Preparedness Association Gold Medal in 1988 for contributions to strategic defense. He was president of ASNE from 1985–1989. He received his B.S. in mathematics from Queens College his M.A. in mathematics from Columbia University his M.S. in electrical engineering from U.S. Naval Postgraduate School and his Ph.D. in electrical engineering/applied mathematics from Polytechnic University. He w

Changing threat requirements and radical budget shifts imply that Navy operational needs will broaden and engineering solutions will face tougher constraints. Existing and emerging technology promise increased combat capability in smaller packages;space-based assets will allow operator orchestration of widely dispersed naval units via connectivity attributes previously unavailable. Tactical data relay by downlink may permit reallocation of responsibilities among several platforms, space, air, or seaborne, so ships can be outfitted for custom-use (sensing, unique data processing, high-firepower) and optimized to meet specific mission needs. These evolving capabilities demand a fresh look at ship concepts and prospective force structures consistent with global and fiscal realities. Warfighting performance formerly unknown in small ship design may offer a very effective solution to the intricate, interacting issues of falling defense budgets, diverse operational requirements and complex national priorities. Multimission ships which take advantage of new or current technology to reduce ship size, manning and cost could be affordable in sufficient numbers to meet our continuing worldwide obligations, complement our larger ships' force structure, and produce a balanced fleet. These same ships could satisfy U.S. maritime needs beyond the Navy and improve export trade through foreign military sales (FMS).

关键词： Naval Warfare

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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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