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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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Modular scintillation cameras: A progress report

Modular scintillation cameras: A progress report

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Medical Imaging II 1988

作者： Aarsvold, J.N. Barrett, H.H. Chen, J. Landesman, A.L. Milster, T.D. Patton, D.D. Roney, T.J. Rowe, R.K. Seacat, R.H. Strimbu, L.M. University of Arizona Program in Applied Mathematics TucsonAZ85721 United States University of Arizona Optical Sciences Center TucsonAZ85721 United States University of Arizona Department of Radiology University Medical Center TucsonAZ85724 United States University of Arizona Department of Physics TucsonAZ85721 United States IBM Corporation General Products Division Department 78G/21-2 TucsonAZ85744 United States University of Arizona Department of Electrical and Computer Engineering TucsonAZ85721 United States

Modular scintillation cameras are gamma cameras with relatively small crystal faces, a small number of photomultiplier tubes (PMTs), and independent processing electronics. Our prototypical module has a 10 cm square crystal face, four PMTs, and digital processing electronics. Scintillation event information is transferred to images by mapping digitized PMT response combinations to optimal position estimates of event locations. In our prototype, a look-up table is used to perform this mapping. To encode scintillation event information more effectively, we use nonlinear compression of each of the PMT signals. Also introduced are logarithmic matched filtering and likelihood windowing, two processing techniques that result from exploitations of the Poisson model of the distribution of photopeak events. Logarithmic matched filtering is a method of obtaining estimates of mean detector response functions having greater accuracy than that indicated by the digitization of the PMT responses. Likelihood windowing is the utilization of a likelihood threshold, rather than the familiar energy window, as a discriminant of photopeak and scatter events. We have implemented each of the above on our prototypical module. Performance characteristics of this module include energy resolution of 10% full width at half maximum (FWHM) at 140 keV and spatial resolution of better than 4mm FWHM over 90% of the crystal. © 1988 SPIE. All rights reserved.

关键词： Photomultipliers

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DATA MULTIPLEX SYSTEM (DMS) - ASPECTS OF FLEET INTRODUCTION

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NAVAL ENGINEERS JOURNAL 1988年第6期100卷 41-47页

作者： BLACKWELL, LM Luther M. Blackwell:is presently the Data Multiplex System (DMS) program manager in the Bridge Control Monitoring and Information Transfer Branch of the Naval Sea Systems Command (NavSea). He graduated from the University of Maryland in 1964 receiving his BS degree in electrical engineering. After graduating he was employed in the Bureau of Ships where he held project engineering assignments on various ships entertainment magnetic tape recording fiber optics computer mass memory and information transfer systems. He has also pursued graduate studies in engineering management at The George Washington University.

The Data Multiplex System (DMS) is a general-purpose information transfer system directed toward fulfilling the internal data intercommunication requirements of a variety of naval combatant ships and submarines in the 1990–2000 time frame. The need for a modern data transfer system of the size and capability of DMS has increased as various digital control systems throughout naval ships have adopted distributed processing architectures and reconfigurable control consoles, and as the quantity of remotely sensed and controlled equipment throughout the ship has increased manyfold over what it was in past designs. Instead of miles of unique cabling that must be specifically designed for each ship, DMS will meet information transfer needs with general-purpose multiplex cable that will be installed according to a standard plan that does not vary with changes to the ship's electronics suite. Perhaps the greatest impact of DMS will be the decoupling of ship subsystems from each other and from the ship. Standard multiplex interfaces will avoid the cost and delay of modifying subsystems to make them compatible. The ability to wire a new ship according to a standard multiplex cable plan, long before the ship subsystems are fully defined, will free both the ship and the subsystems to develop at their own pace, will allow compression of the development schedules, and will provide ships with more advanced subsystems. This paper describes the DMS system as it is currently being introduced into the fleet by the U.S. Navy. The results of its design and implementation in the DDG-51 and LHD-1 class ships are also presented.

关键词： Multiplexing Equipment

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NTDS - A PAGE IN NAVAL HISTORY

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NAVAL ENGINEERS JOURNAL 1988年第3期100卷 53-61页

作者： SWENSON, EN MAHINSKE, EB STOUTENBURGH, JS Capt. Erick N. Swenson USNR (Ret.):is a project manager for special projects in the Surface Ship Systems Division Hughes Aircraft Company Fullerton Calif where he has been employed since his retirement from the U.S. Navy in 1975. Originally trained as an electronics technician during WWII in the Captain Eddy program he later received a BS degree in electrical engineering from the University of Rochester Rochester N. Y. in 1950. Subsequent engineering education was received at the University of Pittsburgh Pittsburgh Penn. and the Naval Postgraduate School Monterey Calif. After commissioning he was ordered to duty as the electronics division officer on the USSMissouri(BB-63) and electronics ships superintendent at Hunters Point Naval Shipyard San Francisco Calif. When the design of the Naval Tactical Data System began in the mid-1950s Lt. (j.g.) Swenson was ordered to the Bureau of Ships Navy Department Washington D.C. as the junior engineering duty only officer assigned to the project. From 1962 to 1965 LCdr. Swenson was assigned as the BuShips technical representative on the program at Remington Rand Univac St. Paul Minn. For the next ten years he returned to BuShips/NavSea/NAVSEC as the NTDS project officer. During this time the project expanded considerably foreign military sales were heavily involved and interoperability with other services and countries were established. His final effort on active duty was to instigate the redesign of the previousSpruanceclass destroyers into the newerAdmiral Kiddclass improvement program. He is a registered professional electrical engineer in the State of California listed inWho's Who in the Worldis a life member of ASNE and chairman of the Long Beach/Greater LA Section. Capt. Edmund B. Mahinske USN (Ret.):is an alumnus of the U.S. Naval Academy the Massachusetts Institute of Technology and the Harvard Business School. His technical background is in electronics and he specialized in the management of programs involving the application of comp

A little over thirty years ago, a group of naval engineers were assembled by the Bureau of Ships to develop a new system approach to the combat information center (CIC). The CIC of World War II, with its “grease pencil” plots and voice telling of tactical information from sensors and other ships, could no longer provide the timely, coordinated reaction to postwar threats. This project group led the Navy into the new world of large-scale, high-speed digital electronics and into a new mode of conducting naval warfare as well. There were no off-the-shelf computers of the requisite capability, size and reliability; what were available were monstrous vacuum tube computers. There were no display equipments that were “conversant” in both the digital language of the computer and the analog language of the sensors and the weapon systems. Who ever heard, at that time, of a computer running a tactical communication net automatically? It was hard enough to find sufficient numbers of engineers who knew what a digital computer was. This paper, by three naval engineers in the implementing engineering office, depicts the evolvement of the Naval Tactical Data Systems (NTDS) as they saw it. It discusses the problems that stemmed from the transition from the old world of analog into the new digital world, the system concepts that steered the development; the key decisions that were made; new electronic equipment and processes that became necessary; and the need of the mangagement to face the real world of deadlines, ship schedules and operational requirements.

关键词： NAVAL WARFARE

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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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When will we have true heterogeneous databases? 87

When will we have true heterogeneous databases?

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Proceedings of the 1987 Fall Joint computer Conference on Exploring technology: today and tomorrow

作者： A. K. Elmagarmid Computer Engineering Program 121 Electrical Engineering East Building The Pennsylvania State University University Park PA

ISBN: (纸本)9780818608117

A heterogeneous distributed database is a system of interconnected DBMSs that use different strategies for data and transaction management. Though issues such as universal query languages, and global view and schema integration have been investigated, transaction management issues introduced by the integration of separate database management systems into one global database have not been widely addressed in the *** most disturbing to me is the general misunderstanding in the database community as to what a heterogeneous database really is. Many people seem to refer to distributed databases as heterogeneous *** interest to me are questions relating to transaction support in the heterogeneous database environment. Two basic approaches are possible in order to integrate differing DBMS's. The first approach integrates transaction management policies into one global transaction manager that handles subtransactions accessing the heterogeneous database. The second is based on hierarchical composition of transaction management policies. In the latter approach, software is added on top of existing systems whenever needed (Gligor and Luckenbaugh, Interconnecting Heterogeneous Database Management Systems, IEEE computer January 1984).The heterogeneous database research group at Penn State consists of three students along with myself. We are looking at concurrency control (Y. Leu), recovery (D. Mannai), and deadlock issues (I. Mahgoub). In this panel I would like to discuss the following set of related questions:Which of the problems are due to DBMS integration and not due to heterogeneity?How is the consistency of heterogeneous databases defined?How does serializability apply to heterogeneous databases?How strict must the definition of database autonomy be? How does it complicate transaction management issues?How important are atomic updates in this environment? How often are they expected?Are we likely to have generalized solutions to the problem of co

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An automated medical record system for a skilled nursing facility

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Journal of Medical Systems 1987年第5期11卷 367-380页

作者： Weiler, Philip G. Thorpe, Linda Walters, Richard Chiriboga, David From the Department of Community Health Center for Aging and Health United States the Department of Electrical and Computer Engineering Division of Computer Science University of California Davis United States D-M Information Systems Inc. United States the Clinical Gerontology Program School of Allied Health Sciences University of Texas United States

This paper reports on the development of an on-line automated medical record system suitable for nursing homes. The software was written in standard MUMPS (Massachusetts General Hospital Utilities Multi-programming System) and is easy for the first-time user to operate. The data managed by the system may be divided into four major components, including text tables, the hierarchical problem dictionary, the patient admission data, and the care plan data. The system met all of the project's objectives and has been enthusiastically received by the nursing home staff. © 1987 Plenum Publishing Corporation.

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Some results in optimal hierarchical estimation

Some results in optimal hierarchical estimation

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IEEE Conference on Decision and Control

作者： S. Roy P. Bhimasankaram R. A. Iltis Department of Electrical and Computer Engineering University of California Santa Barbara CA USA Statistics and Applied probability program University of California Santa Barbara CA USA

The primary objective of this paper is to review several results available in the statistical literature pertaining to the problem of hierarchical estimation. Some relevant extensions are derived for the problem of reconstructing the globally optimal estimate based on local estimates transmitted by feeder nodes. Their utilisty is next demonstrated with characterizations and examples pertaining to common scenarios in decentralized estimation problems.

关键词： Sensor systems Noise measurement Optimal control Sensor phenomena and characterization Signal processing Costs Fault tolerant systems Sensor fusion Particle measurements Statistics

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Infornation Modeling and Analysis of Event Related Potentials

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IEEE Transactions on Biomedical engineering 1987年第12期BME-34卷 928-937页

作者： William J. Williams Howard Shevrin Robert E. Marshall Electrical Engineering and Computer Science Department and the Bioengineering Program University of Michigan Ann Arbor MI USA Department of Psychiatry and Psychology University of Michigan Ann Arbor MI USA Department of Neurology University of Michigan Ann Arbor MI USA

An approach to the analysis of event related potentials (ERP) based on information theory is described. The amount of information in cortical potentials evoked by words briefly presented by tachistoscope is measured by a transinformation method. The inputs to the communication channel are four word categories. One category is composed of pleasant words, another of unpleasant words, both drawn from the Osgood semantic differential research, and two categories are composed of word stimuli related to a psychiatric patient's complaints. The patients chosen for study exhibit either phobias or pathological grief reactions. The method allows ERP's to be mapped into transinformation profiles that reveal time intervals during the poststimulus ERP favorable to the transmission of information concerning the word category presented. The transinformation model results for actual and synthetic data are discussed.

关键词： Enterprise resource planning Mutual information Psychology Voltage Information analysis Information theory Communication channels Pathology Biomedical engineering Psychiatry

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Interface structure and optical properties of quantum wells and quantum boxes

Journal of Vacuum Science & Technology B: Microelectronics P...

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Journal of Vacuum Science & Technology B: Microelectronics Processing and Phenomena 1987年第4期5卷 1204-1208页

作者： P. M. Petroff J. Cibert A. C. Gossard G. J. Dolan C. W. Tu Materials Program and Department of Electrical and Computer Engineering University of California Santa Barbara California 93106 Laboratoire de Spectrometrie Physique BP 87 38402 St. Martin d′Heres Cedex France AT&T Bell Laboratories Murray Hill New Jersey 07974

We investigate two types of GaAs–GaAlAs interfaces in single quantum wells: (a) The abrupt interface produced by growth interruption during molecular‐beam epitaxy; (b) the interdiffused interface produced by Ga+ ion implantation and annealing. The abrupt interfaces are shown to contain islands with sizes ≲1.5 μm. The ion implanted and interdiffused interfaces are characterized by an error function Al concentration profile. The Ga and Al interdiffusion is found to be markedly enhanced (up to ≊100 times at 900 °C) following the ion implantation and annealing. Quantum well boxes (QWB) are produced using the implantation enhanced interdiffusion (IEI) process. The new cathodoluminescence spectral lines observed in the analysis of QWB’s are attributed to three‐dimensional carrier confinement in the potential wells induced by locally enhanced interdiffusion.

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