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A dISTRIBUTEd MEdIA ACCESS PROTOCOL FOR PACKET RAdIO NETWORKS ANd PERFORMANCE ANALYSIS .2. NETWORK SET-UP TIME ANd dATA RATE

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INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS 1995年第1期8卷 49-63页

作者： PONd, LC LI, VOK Communication Sciences Electrical Engineering Systems University of Southern California Los Angeles CA 90089-2565 U.S.A. Lawrence C. Pond received the M.Sc. and Ph.D. degrees in electrical engineering from the University of Southern California in 1983 and 1990 respectively. Dr. Pond is currently a scientist at Hughes Space and Communications Company having joined in 1980. He has worked in the fields of communication system design mobile communication network and spacecraft payload design. He is currently working on the development of satellite-based ATM transport and switching architectures for BISDN and Defense Information System Network amlications. Dr. Pond is a member of IEEE. Victor O. K. Li was born in Hong Kong in 1954. He received his SB SM and Sc.D. degrees in Electrical Engineering and Computer Science from the Massachusetts Institute of Technology Cambridge Massachusetts in 1977 1979 and 1981 respectively. Since February 1981 he has been with the University of Southern California (USC) LOS Angeles California where he is Professor of Electrical Engineering and Director of the USC Communication Sciences Institute. He has published 150 technical papers and has lectured and consulted extensively around the world. His research interests include high-speed communication networks personal communication networks intelligent networks distributed databases queueing theory graph theory and applied probability. Dr. Li is very active in the Institute of Electrical and Electronic Engineers (IEEE) having been a member of the Computer Communications Technical Committee since 1983 and having served as Chairman from 1987–1989. He served as Chairman of the Los Angeles Chapter of the IEEE Information Theory Group from 1983–1985. He is the Steering Committee Chair of the International Conference on Computer Communications and Networks (IC3 N) General Chair of the 1st Annual IC3N held in San Diego California in June 1992 General Chair and Technical Program Chair of the 4th IEEE Workshop on Comp

In this, the second part of a two-part paper, the required time for establishing a mobile packet radio network using the virtual circuit and time division multiple access protocol developed in Part 1 is analysed. Tools are developed to determine the virtual circuit and network set-up times in terms of the channel bandwidth allocated to establish and maintain the network. The tools are then extended to include the effects of user mobility. Then these results are combined with the network capacity results of Part 1 to analyse the trade-off between the data rate and set-up time of the network. Next a hierarchical architecture is proposed and the network data rate versus set-up time trade-off of this architecture is analysed using these tools. This architecture is shown to both provide a higher data rate and establish faster than flat networks of the same number of nodes.

关键词： PACKET RAdIO NETWORK EPLRS dISTRIBUTEd NETWORK TdMA VIRTUAL CIRCUITS MULTIHOP NETWORK BOUNdEd dELAY MOBILITY NETWORK SET-UP TIME HIERARCHICAL NETWORK NETWORK dATA RATE

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Steady‐state security evaluation of electrical power systems by means of artificial neural network

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European Transactions on Electrical Power 1995年第2期5卷 91-97页

作者： Chiodo, E. Menniti, d. Testa, A. Picardi, C. Elio Chiodo (1959) received the degree in Electronics Engineering in 1985 and the Ph.D. degree in Computational Statistics both from the University of Naplefltaly. He is a Researcher at the Department of Electrical Engineering of the University of Naples and a member of the Italian Statistical Society. His areas of interest include probabilistic methods applied to electric power systems analysis. (University of Naples Fedrrico 11. Electrical Engineering Dept.via Claudio 21 1-80125 Naplefltaly T +3981/7683226 Fax+3981/2396897) Daniele Menniti (1958) received the degree in Electrical Engineering from the University of Calabria. Cosenzataly and the Ph.D. degree in Electrical Engineering from the University of NapleslItaly in 1984 and 1989 respectively. He is a researcher at the Electronic. Computer and Systems Science Department of the University of Calabria. Italy. Hiscurrent research interests concern electric power system analysis real-time control and automation. (University of Calabria Electronic Computer and Systems Science Dep. Arcavacataji Rende (CS). 1-87036 CosenzdItaly T +39984/494707. Fax +39984/4947 13) Alfredo Testa (1950) received the degree in Electrical Engineering from the University of Naples/Italy in 1975. He is an Associate Professor in Electrical Power Systems at the Department of Electrical Engineering of the University of Naples. He is engaged in researches on electrical power systems reliability and harmonic analysis. (University of Naples Federico 11. Electrical Engineering Dep. via Claudio '2 1 1-80 I25 NapleslItaly T + 39 8 I/7 68 3'2 11. Fax+3981/2396897) Ciro Picardi (1949) received the degree in Electronics Engineering from the University of Naples/Italy in 1975. He is currently Associate Professor in Process Control at the Department of Electronic Computer and System Science of the University of Calabria. Italy. His current research interests are in the area of electrical drives robotics neural networks and fuzzy control. (University of Calabria Electronic. Compu

An artificial‐neural‐network (ANN) application for steady‐state security evaluation of electrical power systems is presented. Such application is based upon a combined use of a multilayer back‐propagation neural network and of an opportune electrical system model, previously proposed by some of the authors. In the paper, the definition of steady‐state security and the problems arising from its on‐line evaluation are briefly recalled. Then, the ANN utilized is described with particular reference to the solutions adopted by the authors. Afterwards, some remarks on the system model utilized are reported. Finally, numerical applications on the AEP‐14 bus system are presented and the results obtained with different ANN configurations are analyzed. Copyright © 1995 John Wiley & Sons, Ltd.

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GROUNd-WATER MONITORING statistics UPdATE .1. PROGRESS SINCE 1988

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GROUNd WATER MONITORING ANd REMEdIATION 1994年第4期14卷 148-158页

作者： dAVIS, CB MCNICHOLS, RJ Charles B. Davis is principal statistician with Environmet- rics & Statistics Ltd. (EnviroStat 1853 Wellington Court Henderson NV 89014). After receiving his M.S. in mathematics and statistics and Ph.D. in statistics from the University of New Mexico he joined the Mathematics Department of the University of Toledo to establish its graduate program in statistics with emphasis on consulting and applications. He and McNichols became involved in consulting and research related to statistical issues arising in RCRA ground water monitoring regulation in 1985 and formed EnviroStat in 1990. Davis left academia in 1992 to concentrate on environmental statistics. Roger J. McNichols is professor and chairman of the Industrial Engineering Department at The University of Toledo (Toledo OH 43606). After receiving his Ph.D. in industrial engineering from The Ohio State University he joined the faculty of Texas A and M University where he directed the Maintainability Engineering Graduate Program at Red River Army Depot. At University of Toledo he is also chairman of the Systems Doctoral Program and has served as associate dean of engineering. His research and consulting interests include reliability quality control manufacturing environmental monitoring mathematical modeling and applied statistics.

Current federal ground water monitoring statistical regulation dates from the revised RCRA Subtitle C Final Rule of 1988. That rule was a considerable advance over previous RCRA statistical rules. However, two major problem areas remained: facility-wide false positive rate (FWFPR) control and spatial variability. Progress has been made in the 1991 Subtitle d Final Rule and in guidance;the 1992 Addendum to Interim Final Guidance in particular includes a substantial conceptual advance toward resolving the FWFPR problem. Other areas of improvement include normality testing and distribution assumptions, dropping the four independent samples per monitoring period requirement, allowing a preliminary evaluation short of a 40 CFR Part 258 Appendix II assessment upon finding a statistically significant increase, and suggesting superior alternatives to analyses of variance (ANOVAs) and tests of proportions. The problem of dealing with natural spatial variability remains. Although certain techniques listed in the regulations can control for inherent spatial variability and the performance standards require doing so ''when necessary,'' little attention has been paid to the ubiquity of such spatial variation. Moreover, regulatory traditions favoring upgradient-downgradient comparisons often make control of natural spatial variation difficult and ineffective. With new, lined facilities easily implemented statistical solutions are available;however, dealing with the several existing solid waste facilities which will now be regulated under Subtitle d will present major challenges. In short, the 1988 revision of the Subtitle C rules made it more possible to provide statistically sound monitoring programs, and there has been steady progress since then. Challenges remain, however. These vary from state to state, particularly with regard to controlling false positives and false negatives in the presence of natural spatial variability.

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ROBUST dESIGN OF A POLYSILICON dEPOSITION PROCESS USING SPLIT-PLOT ANALYSIS

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QUALITY ANd RELIABILITY ENGINEERING INTERNATIONAL 1994年第2期10卷 123-132页

作者： CANTELL, BS RAMIREZ, JG Digital Equipment Corporation 77 Reed Road Hudson MA 01749-9987 U.S.A Brenda Cantell received a M.S. in Industrial Engineering from Rensselaer Polytechnic Institute (1988) and a B.A. in Mathematics from Western New England College (1987). She will receive an M.S. in Applied Statistics from Worcester Polytechnic Institute in December 1993. She is a Senior Quality Engineer within the Semiconductor Operations (S.C.O.) business in Digital Equipment Corporation. Her job responsibilities include the application of applied statistics to semiconductor manufacturing processes and the development and deployment of quality tools and techniques. She is also a Certified Quality Engineer through the American Society for Quality Control and a member of the American Statistical Association. José Ramirez received a Ph.D. in Statistics (1989) and an M.S. in Applied Statistics (1985) from the University of Wisconsin-Madison and a Degree in Mathematics (1982) from the University Simón Boliívar in Caracas Venezuela. He is currently a member of the Quality and Reliability Group within the Semiconductor Operations at Digital Equipment Corporation where he consults and teaches statistics. He also facilitates small group improvement activities using total quality management tools and creative problem solving techniques. Before joining Digital he was at the Center for Quality and Productivity Improvement University of Wisconsin-Madison where he conducted research on quality improvement methodologies assisted in the preparation and administration of class notes for short courses for engineers and statisticians and supervised a weekly seminar on topics in industrial quality and productivity improvement. Prior to that he served as a statistical consultant at the Statistical Laboratory. University of Wisconsin-Madison. José is a member of the American Society for Quality Control the American Statistical Association and a Certified Quality Engineer.

The technique used for the analysis of experimental data must be appropriate for the design and treatment structures of the experiment;failure to take this into account can produce misleading results. This paper illustrates how split-plot designs can be used for the analysis of robust design experiments. In particular, the polysilicon deposition process data presented by ph.d.e(1) is analysed, and comparisons are made between the split-plot analysis of the raw data and the analysis conducted using signal-to-noise ratios. In addition, we demonstrate how the split-plot analysis provides information about interactions between control and noise factors, and how interaction plots can be used to assess the performance of the control factors across the levels of the noise factors. This information is particularly important to select the settings of the control factors that minimize the variation in the response induced by the noise factors.

关键词： dESIGN OF EXPERIMENTS INTERACTION PLOT ROBUST dESIGN SPLIT-PLOT dESIGN POLYSILICON dEPOSITION PROCESS

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ACQUISITION REFORM ANd BEST PROdUCT PROCUREMENT - AN ENGINEERING VIEW

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NAVAL ENGINEERS JOURNAL 1994年第6期106卷 41-57页

作者： FISHER, dA SKOLNICK, A He has been involved with several weapon system developments. Among these were the Trident II fire control and navigation systems the BSY-I Anti-Submarine Warfare System and the Navy standard computers (UYK44 and EMSP). He served as manager of the Digital Circuits Engineering Branch and was then appointed as manager of the Automatic Test Equipment (ATE) Technology Division. As manager of the ATE Technology Division he was responsible for the SP-23 Fire Control System Support Project the SP-24 Navigation Project and the Fleet Progressive Maintenance Program (2M/ATE). This Division was responsible for selection and application of electronic product technology and for developing fleet test and repair techniques. He holds a B.S. in Electrical Engineering from the University of Evansville and is currently pursuing a Masters of Public Administration at Indiana University-Purdue University Indianapolis. Dr. Alfred Skolnick:retired from the Navy in 1983 with the rank of captain. He is president of System Science Consultants (SSC) specializing in strategic planning technical program definition technology assessment and engineering analyses on selected matters of national interest. Dr. Skolnick taught mathematics and management sciences at University of Virginia and Marymount University. He is adjunct faculty at Northern Virginia Community College. From 1985 to 1989 he was president of the American Society of Naval Engineers. In the Navy he served at Applied Physics Laboratory/The Johns Hopkins University then aboard USSBoston(CAG-1) and played leading roles in several weapon system developments inertial navigation (Polaris) deep submergence (DSRV) and advanced ship designs (SES). He later was director Combat System Integration Naval Sea Systems Command and head Combat Projects Naval Ship Engineering Center. In 1975 he became a major project manager and led the Navy's High Energy Lasers Program in 1981 he was assigned all Navy Directed Energy Weapons development efforts. He was vice president advanced tech

The military services are being moved in the direction of performance-based specifications and standards. They are being steered against dictating ''how to'' produce an item since such action forecloses on the ability to gain access to components or technology that may have a commercial equivalent. Why should the engineering community embrace the new approach? Aside from the obvious weight of it being approved policy, therefore currently mandated, it warrants examination because it is the correct approach at this time when applied to appropriate products. Military specifications and standards are to be displaced then, by acceptable alternative contractor design solutions. Industry bidders will be allowed to propose the particular design details, permitting procurement flexibility by contractually citing only system level or interface requirements, both physical and functional. Hopefully, this can broaden the industrial base and increase competition with reduced costs to follow. Conceptually, the approach appears both performance-sensible and cost-attractive (there are, of course, consequent risks) but how does implementation proceed? Is it possible to pursue the goals envisioned along paths that are not in themselves experimental? Can the American postulate, minimal loss of life and limb to U.S. military people, continue to be honored? Experience and track record elsewhere imply encouraging possibilities in select situations-useful prospects are identified and discussed in practical terms.

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MOdAL TEST OF JONES,JOHN,PAUL (ddG-53) MAST ANd MAST-MOUNTEd ANTENNAS

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NAVAL ENGINEERS JOURNAL 1994年第2期106卷 110-117页

作者： MCLEAN, M HILL, J COBB, R RANdALL, F Mark McLean:has been with the Naval Sea Systems Command for eight years and is currently with Code 03K. He is responsible for survivability assessment of combat systems equipment. He has participated in all U.S. Navy ship shock tests conducted since 1985 and is responsible for failure assessment and redesign efforts for numerous combat systems equipment. He was selected by the NavSea Program Offices to be a member of the damage assessment teams providing early inspection in the Samuel B. Roberts (FFG-58) and Princeton (CG-59) incidents. Mr. McLean graduated from the University of Virginia in 1983 with an MS degree in chemical engineering. Jerry Hill:has been with NKF Engineering Inc. for twelve years. Currently managing the structural dynamics department Mr. Hill is responsible for numerous survivability related analysis and design efforts. This includes dynamic mathematical simulation and prediction field testing and qualification and full-scale ship shock testing. Mr. Hill graduated from the University of Maryland with a BS degree in mechanical engineering. He is a registered Professional Engineer. Dr. Richard Cobb:has been with NKF Engineering Inc. as a senior engineer since 1990. He is involved with research and development projects including dynamics modal testing vibration design instrumentation and underwater explosion. Prior to joining NKF he was an instructor of mechanical engineering at Virginia Tech. Dr. Cobb holds a Ph.D. in mechanical engineering from Virginia Tech with dissertation research in the areas of experimental modal analysis and frequency response function estimation using Fast Fourier transform methods. Fred Randall:has been manager of the noise shock and vibration department at Bath Iron Works since 1987. As such he is responsible for all dynamic measurements conducted by the shipyard. From 1982 to 1987 he was with TRW in the survivability department conducting investigations of shock propagation structural media interaction and soils modeling and analysis. Mr. Randall gr

A modal test of the John Paul Jones (ddG-53) mainmast structure and mast-mounted antennas was conducted. The test was part of a larger effort to accurately determine dynamic characteristics of the ''as-built'' mast/antenna system and survivability in the vibration and underwater explosion (UNdEX) shock environment. Previous mathematical analysis of the ddG-51 class mast and antennas predicted response acceleration levels during a shock trials scenario to be excessive in some areas. The modal test results now provide, however, confirmed dynamic response characteristics including mode shapes, frequencies, and damping for the structure. The test data accounts for the flexibility of ship's structure including the deckhouse supporting the mast. In addition, the natural frequencies of the antennas were determined for the response range of the mast structure with the flexibility of the supporting foundations taken into account. Using the test results, a finite element model of the mast structure and antennas was built accurately representing the dynamic characteristics of the system. dynamic transient shock analysis was conducted to provide response predictions of the mast and antennas using the validated model. Any potential response amplification conditions that might result in failure during shock trials were identified.

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THE CALLING(SM) NETWORK - A GLOBAL WIRELESS COMMUNICATION-SYSTEM

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第1期12卷 45-61页

作者： TUCK, EF PATTERSON, dP STUART, JR LAWRENCE, MH Calling Communications Corporation. 1900 West Garvey Ave South. Suite 200 West Covina CA 91790 USA. Chairman of Calling Communications Corporation. He is also the Managing Director of Kinship Venture Management Inc. the general partner of Kinship Partners 11 and a General Partner of Boundary the general partner of The Boundary Fund. As a venture capitalist he has founded or participated in founding several telecommunications companies including Calling Communications Corporation Magellan Systems Corporation manufactures of Global Positioning System receivers Applied Digital Access manufacturer of DS-3 test access and network performance monitoring equipment Endgate Technology Corporation specialists in satellite phased array antennas and Poynting Systems Corporation. now a division of Reliance Corporation manufacturers of fibre optic transport equipment. He was a founder of Kebby Microwave Corporation where he invented the first solid-state. frequency-modulated commercial microwave link system. The company was acquired by ITT Corporation where he rose to the position of V.P. and Technical Director of ITT North America Telecommunications Inc. Subsequently he was V.P. of Marketing and Engineering at American Telecommunications Inc. (ATC). He was founding Director of American Telecom Inc. a joint venture between ATC and Fujitsu and has served on more than 20 boards of directors including those of three public companies. He has authored articles on microwave engineering and telephone signalling and was a contributor to Reference Data For Radio Engineers. He is a graduate of the University of Missouri at Rolla where he was later awarded an honorary Professional degree and serves on its Academy of Electrical Engineering. Mr Tuck is a Senior Member of the IEEE a Fellow of the Institution of Engineers (Australia) a Professional Member of the AIAA and a registered professional engineer in three states. More than 25 years of experience in the telecommunications industry where he has been responsibl

There is a very large demand for basic telephone service in developing nations, and remote parts of industrialized nations, which cannot be met by conventional wireline and cellular systems. This is the world's largest unserved market. We describe a system which uses recent advances in active phased arrays, fast-packet switching technology, adaptive routeing, and light spacecraft technology, in part based on the work of the Jet Propulsion Laboratory and on recently-declassified work done on the Strategic defense Initiative, to make it possible to address this market with a global telephone network based on a large low-Earth-orbit constellation of identical satellites. A telephone utility can use such a network to provide the same modern basic and enhanced telephone services offered by telephone utilities in the urban centres of fully-industrialized nations. Economies of scale permit capital and operating costs per subscriber low enough to provide a service to all subscribers, regardless of location, at prices comparable to the same services in urban areas of industrialized nations, while generating operating profits great enough to attract the capital needed for its construction. The bandwidth needed to support the capacity needed to gain these economies of scale requires that the system use K(alpha)-band frequencies. This choice of frequencies places unusual constraints on the network design, and in particular forces the use of a large number of satellites. Global demand for basic and enhanced telephone service is great enough to support at least three networks of the size described herein. The volume of advanced components, and services such as launch services, required to construct and replace these networks is sufficient to propel certain industries to market leadership positions in the early 21st Century.

关键词： LOW EARTH ORBIT SATELLITE COMMUNICATIONS FAST PACKET SWITCHING EARTH FIXEd CELLS AdAPTIVE ROUTEING LIGHT SPACECRAFT K(A) BANd phASEd-ARRAY ANTENNAS

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COMPARISON OF 2 INTEGRATEd METHOdS FOR THE COLLECTION ANd ANALYSIS OF VOLATILE ORGANIC-COMPOUNdS IN-GROUNd WATER

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GROUNd WATER MONITORING ANd REMEdIATION 1993年第3期13卷 118-123页

作者： PATTERSON, BM POWER, TR BARBER, C Bradley M. Patterson (Private Bag P.O. Wembley Western Australia 6014) earned his B.S. (with honors) in organic chemistry in 1982 at the University of Western Australia and is an experimental scientist at CSIRO Division of Water Resources. Terry R. Power (Private Bag P.O. Wembley Western Australia 6014) has a diploma in applied chemistry and is a senior technical officer at CSIRO Division of Water Resources. Chris Barber (Private Bag P.O. Wembley Western Australia 6014) has a B.S. in geology and a Ph.D. in geochemistry and is currently program manager Contaminant Hydrology in CSIRO Division of Water Resources.

The principal difficulties with determinations of volatile organic compounds (VOCs) in ground water are the reliability of sampling procedures and analytical methods. Two integrated methods have been developed for routine sampling, processing, and analysis of VOCs in ground water. These methods involve in situ collection of ground water using a modified syringe sampler from PVC piezometers or using dedicated glass syringes from stainless steel multilevel bores. The samples are processed in the syringe using purge and trap or microsolvent extraction and analyzed by GC/MSd. The modified purge-and-trap method is time-consuming and limited to volatile organic compounds. However, it is extremely sensitive and flexible: the volume of sample used can be varied by the use of different-size glass syringes (sample volumes from 1 to 100 mL). In cases where extremely low sensitivity (<10 mg 1-1) is not critical, the microextraction technique is a more cost-effective method, allowing twice as many samples to be analyzed in the same time as the purge-and-trap method. It enables less volatile compounds such as polynuclear aromatic hydrocarbons, phenol, and cresols to be analyzed in the same GC run. Also, the microextraction method can be used in the field to avoid delays associated with transportation of ground water samples to the laboratory.

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APPLICATION OF ELECTROMAGNETIC LOGGING TO CONTAMINATION INVESTIGATIONS IN GLACIAL SANd-ANd-GRAVEL AQUIFERS

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GROUNd WATER MONITORING ANd REMEdIATION 1993年第3期13卷 129-138页

作者： WILLIAMS, JH LAphAM, WW BARRINGER, TH John H. Williams received an M.S. in geology from Penn State University in 1980 and has worked for the U.S. Geological Survey since that time. He currently is the ground water specialist for the New York District (P.O. Box 1669 Albany NY 12201) and the borehole geophysics specialist for the Northeastern Region. He is also an instructor for the National Ground Water Association course on aquifer test methods. His primary interest is the application of borehole geophysics to ground water studies. Wayne W. Lapham has been employed as a hydrologist with the U.S. Geological Survey since 1976. He currently works for USGS as a ground water specialist for the National Water-Quality Assessment Program (MS 413 Reston VA 22092). He received a B.S. degree in mechanical engineering from Northeastern University in 1969 an M.S. in geology from the University of Massachusetts in 1975 and a Ph.D. in hydrology from the University of Arizona in 1988. He has been involved with various aspects of ground water hydrology including resource appraisal and ground water modeling. Thomas H. Barringer is the statistical methods specialist for the New Jersey District of the U.S. Geological Survey (810 Bear Tavern Rd West Trenton NJ 08628). His interests include spatial statistics and the application of statistical methods to hydrological problems. He has a joint M.S. in regional planning and regional science and a PhD. in regional science from the University of Pennsylvania.

Electromagnetic (EM) logging provides an efficient method for high-resolution, vertical delineation of electrically conductive contamination in glacial sand-and-gravel aquifers. EM, gamma, and lithologic logs and specific conductance data from sand-and-gravel aquifers at five sites in the northeastern United States were analyzed to define the relation of EM conductivity to aquifer lithology and water quality. Municipal waste disposal, septic waste discharge, or highway deicing salt application at these sites has caused contaminant plumes in which the dissolved solids concentration and specific conductance of ground water exceed background levels by as much as 10 to 20 times. The major hydrogeologic factors that affected EM log response at the five sites were the dissolved solids concentration of the ground water and the silt and clay content in the aquifer. EM conductivity of sand and gravel with uncontaminated water ranged from less than 5 to about 10 millisiemens per meter (mS/m);that of silt and clay zones ranged from about 15 to 45 mS/m;and that of the more highly contaminated zones in sand and gravel ranged from about 10 to more than 80 mS/m. Specific conductance of water samples from screened intervals in sand and gravel at selected monitoring well installations was significantly correlated with EM conductivity. EM logging can be used in glacial sand-and-gravel aquifer investigations to (1) determine optimum depths for the placement of monitoring well screens;(2) provide a nearly continuous vertical profile of specific conductance to complement depth-specific water quality samples;and (3) identify temporal changes in water quality through sequential logging. detailed lithologic or gamma logs, preferably both, need to be collected along with the EM logs to define zones in which elevated EM conductivity is caused by the presence of silt and clay beds rather than contamination.

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CIRCULAR OVERMOdEd WAVE-GUIdE FOR SHIPBOARd USE

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NAVAL ENGINEERS JOURNAL 1993年第2期105卷 39-52页

作者： HUTING, WA WARREN, JW GARNER, PN KRILL, JA William A. Huting:received the B.S.E. degree in electrical engineering from Duke University in 1981 the M.S.E.E. degree from the Georgia Institute of Technology in 1982 and the Ph.D. degree in electrical engineering (electrophysics) from the University of Maryland in 1989. From September 1981 to December 1983 he was a graduate teaching assistant with Georgia Tech. Since January 1984 he has been with The Johns Hopkins University Applied Physics Laboratory where he has principally been involved with the development of circular overmoded waveguides and tapered waveguide transitions for use in naval radar systems. Dr. Huting is a member of the Institute of Electrical and Electronics Engineers. Jeffery W. Warren:received a B.S. degree in 1982 and an M.S. degree in 1984 both in electrical engineering from the University of South Carolina. His thesis research evaluated electro-optical measurements of surface charging of insulators in low-frequency fields. He joined The Johns Hopkins University Applied Physics Laboratory in 1984. Mr. Warren's activities include development and testing of electro-optical systems and the development of high-power low-loss overmoded waveguides. Mr. Warren is a member of the Institute of Electrical and Electronics Engineers. Paul N. Garner: Jr. received the B.S. degree in mathematics and the B.S. degree in mechanical engineering from the University of Maryland in 1973 and 1980 respectively and the M.B.A. degree from the Florida Institute of Technology in 1984. Since 1987 he has been involved with the Cooperative Engagement Capability Program as the lead mechanical engineer and since 1990 he has been with The Johns Hopkins University Applied Physics Laboratory where he is now a member of the Senior Professional Staff. Jerry A. Krill:received the B.S.E.E. and M.S.E.E. degrees from Michigan State University in 1973 and 1974 respectively and a Ph.D. in electrical engineering (electrophysics) from the University of Maryland in 1978. From 1973 to the present he has been with The Johns

Several future Navy combat systems under development require efficient delivery of high power microwave energy from remote transmitters to array antennas. To achieve this requirement, a family of microwave components has been developed and tested. Progress is described in the design and testing of an overmoded circular TE01 mode waveguide applicable to special shipboard needs. Because such a waveguide had originally been developed for low power millimeter band trunkline communications between cities, new theoretical, design, and fabrication techniques had to be developed to meet our specific performance requirements. Moreover, in order to fulfill the combat system requirements, the waveguide would have to withstand harsh military requirements. Over several years the obstacles to the application of overmoded technology to Navy combat systems have been systematically eliminated. The effort has resulted in the invention of several new components, the development and validation of a new computer aided design package, and the implementation of new microwave measurement techniques. The first application of an overmoded waveguide to a combat system element was recently achieved in the successful demonstration of the prototype Cooperative Engagement Capability, and steps toward a production military version of the waveguide have been initiated.

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