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Nonlinear Image Processing III 1992

作者： Schulze, Mark A. Pearce, John A. Department of Electrical and Computer Engineering and Biomedical Engineering Program University of Texas at Austin AustinTX78712 United States

We introduce a continuous time method to analyze the response of median, pseudomedian, average (mean), and midrange filters to certain periodic signals. The filter definitions are generalized to continuous time, and these definitions are applied to periodic signals such as triangle, square, and sinusoidal waves of varying frequencies. These operations yield "amplitude response" measures which are analytic functions of the frequency of the input signal. In addition, a "correlation" measure is defined to indicate the level of distortion introduced by each filter. Examples of this analysis for the median, pseudomedian, average, and midrange filters show similarities and differences among them. Although these theoretical measures do not perfectly demonstrate the performance of the discrete time filters, continuous time analysis does provide valuable insights into the filter behavior. The response of the continuous time median filter shows its susceptibility to high frequency periodic noise and proves, again, the existence of infinite-length bi-valued fast-fluctuating roots of this filter. The pseudomedian filter, in contrast, completely attenuates amplitude-symmetric periodic signals above a certain frequency, and has no infinite-length fast-fluctuating roots. Continuous time filter analogues are therefore an important theoretical tool for understanding the behavior of both linear and nonlinear filters. © 1992 SPIE. All rights reserved.

关键词： Median filters

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An automated charcoal scanner for paleoecological studies

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Palynology 1992年第1期16卷 7-12页

作者： Horn, Sally P. Horn, Roger D. Byrne, Roger Department of Geography and Graduate Program in Ecology University of Tennessee Knoxville TN 37996-1420 United States Department of Electrical and Computer Engineering University of Tennessee Knoxville TN 37996-2100 United States Department of Geography and Museum of Paleontology University of California Berkeley CA 94720 United States

An automated imaging system is described that determines fragment numbers, areas, and size classes of microscopic charcoal in pollen preparations. Charcoal counts made with the scanner are similar to counts made using...

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ACOUSTIC TRANSMISSION OF THE RESPIRATORY SYSTEM USING SPEECH STIMULATION

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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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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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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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SHIP SERVICE electrical SYSTEMS - DESIGNING FOR SURVIVABILITY

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 32-36页

作者： CERMINARA, J KOTACKA, RO John Cerminara:is a principal engineer with Westinghouse Machinery Technology Division Electrical Systems Department. He holds a B.S. degree in electrical engineering from the University of Pittsburgh. He is a registered professional engineer and a member of IEEE ASNE and the Ship Steering Group of the Combat Survivability Division of ADPA. Mr. Cerminara has had over 30 years of multidiscipline experience ranging from engineering and construction in heavy industry to standards and publications. Past assignments include DOE/ NASA wind turbine project manager for Westinghouse and task leader of MTD electrical systems. Most recent assignments have included hull mechanical and electrical (HM&E) distributive system survivability analyses of the LSD-41 mobility mission area and application and validation of NavSea computer-aided design of Survivable Distributive System (CADSDiS) Program. Rolf O. Kotacka:is presently a ship systems engineer in the Ship Systems Engineering Branch of the Naval Sea Systems Command Engineering Directorate where his primary responsibility is ship system survivability. He is a 1977 graduate of SUNY Maritime College where he received his bachelor of engineering degree in marine electrical engineering as well as a U.S. Coast Guard Third Assistant Engineer License and a commission in the U. S. Naval Reserve. Upon graduation Mr. Kotacka was employed by Charleston Naval Shipyard as a field engineer until 1981 where he gained his background in surface ship HM&E systems and equipment. He then transferred to the Supervisor of Shipbuilding Conversion and Repair Groton where he served as a senior electrical engineer monitoring the design and construction of Trident and 688 class submarines and received the Meritorious Unit Citation. Prior to his present position Mr. Kotacka was the life cycle manager for diesel generator sets in the Naval Sea Systems Command's Generators Branch. He has coauthored several papers dealing with power generation for ASE and SNAME. Mr. Kotacka is also a lieutena

This paper highlights the survivability concerns in the design of ship service power systems. The paper gives a brief description of what constitutes a typical ship service electric power system and concentrates on electric power generation and associated controls. Established survivability design principles and guidelines are highlighted and the application of those guidelines are discussed. General Specifications (Gen Specs) for Ships of the U.S. Navy are cited as the cornerstone for design. Specific design criteria are cited as well as the rationale associated with the survivability design guidelines pertaining to power generation and distribution. The application of these survivability design guidelines plus the use of the deactivation diagram/damage tolerance analysis cited in the Gen Spec section 072e will enhance overall design and help ensure survivable electric power systems for surface combatants.

关键词： Warships

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A Monte Carlo model of light propagation in tissue

A Monte Carlo model of light propagation in tissue

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Dosimetry of Laser Radiation in Medicine and Biology 1988

作者： Prahl, S.A. Keijzer, M. Jacques, S.L. Welch, A.J. Department of Electrical and Computer Engineering Biomedical Engineering Program University of Texas at Austin United States Department of Dermatology Wellman Laboratory Harvard Medical School United States

The Monte Carlo method is rapidly becoming the model of choice for simulating light transport in tissue. This paper provides all the details necessary for implementation of a Monte Carlo program. Variance reduction schemes that improve the effiency of the Monte Carlo method are discussed. Analytic expressions facilitating convolution calculations for flat and Gaussian beams are included. Useful validation benchmarks are presented. © 1989 SPIE.

关键词： Monte Carlo methods

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Analysis of light distribution in tissue

Analysis of light distribution in tissue

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Laser Interaction with Tissue 1988

作者： Van Gemert, M.J.C. Jacques, S.L. Sterenborg, H.J.C.M. Star, W.M. Welch, A.J. Academic Medical Centre Experimental Laser Centre Meibergdreef 9 Amsterdam Z.O.1105 AZ Netherlands Laser Application and Information Centre Amsterdam Department of Physics Free University Amsterdam Netherlands Wellmann Laboratory Department of Dermatology Massachusetts General Hospital Boston United States Department of Clinical Physics Rotterdam Radiotherapeutic Institute Rotterdam Netherlands Biomedical Engineering Program University of Texas at Austin Austin United States Electrical and Computer Engineering and Biomedical Engineering

Q-uantitative dosimetry in clinical laser treatment requires information on propagation of light in tissue related to the optical properties of the tissue. This involves the solution of the integro-differential equation of radiative transfer, as well as experimental methods to determine the optical properties involved. These activities are summarized under the name tissue optics. This paper reviews the current status of tissue optics, distinguishing between the cases of: dominant absorption, dominant scattering, and scattering about equal to absorption. Most tissues or phantom tissues of which the optical properties are available show strongly forward scattering. The absorption and scattering data of skin layers show that in many cases scattering is more important than absorption. Under such circumstances, solutions to the transport equation under laser irradiation conditions are currently lacking. © 1988 SPIE. All rights reserved.

关键词： Tissue

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Tissue optics for a slab geometry in the diffusion approximation

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Lasers in Medical Science 1987年第4期2卷 295-302页

作者： Van Gemert, Martin J.C. Welch, Ashley J. Star, Willem M. Motamedi, Massoud Cheong, Wai-Fung Department of Electrical and Computer Engineering Biomedical Engineering Program The University of Texas at Austin Austin Texas United States

This paper solves the radiative transport equation in a slab using the diffusion approximation in one-dimension. The absorption and scattering coefficients as well as the first moment of the phase function are shown to follow directly from measurement of the diffuse transmission and the collimated transmission, and the diffuse reflection. © 1987 Baillière Tindall.

关键词： Absorption and scattering coefficents Anisotropy factor of scattering Diffusion approximation Slab geometry Tissue optics

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SOME PHYSICAL CONCEPTS IN LASER ANGIOPLASTY

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SEMINARS IN INTERVENTIONAL RADIOLOGY 1986年第1期3卷 27-38页

作者： VANGEMERT, MJC WELCH, AJ BONNIER, JJM VALVANO, JW YOON, G RASTEGAR, S *Biomedical Engineering Program The University of Texas at Austin Austin Texas †Department of Cardiology Catharina Hospital Eindhoven The Netherlands ‡During 1984 - 1985 on leave from St. Joseph Hospital of Eindhoven under the sponsorship of the Hospital The Netherlands America Commission for Educational Exchange and The Dutch Organization for the Advancement of Pure Research (ZWO) §Marion E. Forsman Centennial Professor of Electrical and Computer Engineering and Biomedical Engineering

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