作者：
Li, K.Tassoudji, M.A.Shin, R.T.Kong, J.A.Department of Electrical Engineering and Computer Science and Research Laboratory of Electronics
Massachusetts Institute of Technology Cambridge Massachusetts 02139 Kevin Li:received his BS and SM degrees (1990) in Electrical Engineering and EE (Electrical Engineer's) degree (1991) from the Massachusetts Institute of Technology
where he is currently pursuing his PhD in Electrical Engineering. Since 1990 he has been the recipient of a United States Air Force Laboratory Graduate Fellowship. His main research interests include electromagnetic scattering radar cross section prediction and numerical techniques. Mr. Li is a member of Tau Beta Pi and a student member of IEEE. M. Ali Tassoudji:received his BS (1987) and MS (1989) degrees in Electrical Engineering from the University of Michigan
Ann Arbor. Since 1989 he has been a research assistant at the Massachusetts Institute of Technology where he is currently working towards his PhD in Electrical Engineering. His research interests include electromagnetic scattering and propagation modeling of microwave circuits and numerical techniques. Mr. Tassoudji is a member of IEEE and Eta Kappa Nu. Robert T. Shin:received his SB (1977)
SM (1980) and PhD (1984) in Electrical Engineering from the Massachusetts Institute of Technology. Since 1984 he has been a member of the Air Defense Techniques Group at MIT Lincoln Laboratory as a Research Staff member and as a Senior Staff member from 1989. His research interests are in the areas of electromagnetic wave scattering and propagation theoretical model development and data interpretation for microwave remote sensing. He is the coauthor ofTheory of Microwave Remote Sensing(Wiley 1985). Dr. Shin is a member of The Electromagnetics Academy IEEE American Geophysical Union Tau Beta Pi Eta Kappa Nu and Commission F of the International Union of Radio Science. Since 1987 he has served on the Editorial Board of theJournal of Electromagnetic Waves and Applications(JEWA). Jin Au Kong:is Professor of Electrical Enginee
The finite difference-time domain (FD-TD) technique is applied to the solution of Maxwell's equations. A computer program, which can be used to simulate and study numerous electromagnetic phenomena, is developed a...
The finite difference-time domain (FD-TD) technique is applied to the solution of Maxwell's equations. A computer program, which can be used to simulate and study numerous electromagnetic phenomena, is developed and implemented on an IBM 386 compatible personal computer. The FD-TD technique is a useful tool for students in electromagnetics. The technique is flexible and can be applied to many basic EM scattering and radiation problems. Because field solutions are found as a function of time, visualization of the propagation of the EM fields is possible. The FD-TD technique is implemented for a two-dimensional rectangular grid in conjunction with a second-order absorbing boundary condition. Both E- and H-field polarizations are analyzed. Finite objects consisting of dielectric, magnetic and conducting materials, and perfectly conducting infinite ground planes are modeled. Plane wave and line current sources are implemented. In addition to the capability of animating the propagation of the EM fields, radiation and scattering patterns can be generated.
This article describes further efforts to employ the Systems Entity Structure/Model Base framework as a workable foundation for model base management in advanced simulation environments and workbenches. Such managemen...
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This paper documents an experiment performed by The Johns Hopkins University Applied Physics Laboratory to measure the effect of inserting a data bus into a combat system. The experiment was conducted at the Aegis Com...
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This paper documents an experiment performed by The Johns Hopkins University Applied Physics Laboratory to measure the effect of inserting a data bus into a combat system. The experiment was conducted at the Aegis computer Center located at the Naval Surface Weapons Center in Dahlgren, Virginia (NSWC/DL). The purpose of the experiment was to determine whether or not the Aegis Weapon System (the core of the Aegis Combat System) could be operated with a portion of its point-to-point interelement cables replaced by a data bus. The data bus chosen for the experiment employs message broadcasting with receiver selection. A primary goal of the experiment was to minimize the amount of Aegis computer program changes required to accommodate the data bus. The results presented in this paper will show that the experiment was a success. Key certification tests were passed with no computer program changes to the tactical elements and minimal changes in the Aegis tactical executive (ATES) program (less than 110 words changed).
A methodology for the structural life assessment of a ship's structure is suggested. The methodology is based on probabilistic analysis using reliability concepts and the statistics of extremes. In this approach, ...
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A methodology for the structural life assessment of a ship's structure is suggested. The methodology is based on probabilistic analysis using reliability concepts and the statistics of extremes. In this approach, the estimation of structural life expectancy is based on selected failure modes. All possible failure modes of the ship must be investigated and the most likely paths to structural failure identified. For the purpose of illustration two failure modes are considered in this study. They are plate plastic deformation and fatigue cracking. Structural life based on these two failure modes is determined for an example vessel. The methodology determines the probability of failure of the ship's structural components according to the identified failure modes as a function of time. The results can be interpreted as the cumulative probability distribution function (CDF) of structural life. Due to the unknown level of statistical correlation between failure modes, limits or bounds on the CDF of the structural life are established. The limits correspond to the extreme cases of fully correlated and independent failure modes. The CDFs of structural life are determined for two inspection strategies; namely, inspection every year and inspection every two years with a warranty inspection at the end of the first year. The meaning of the results for the case investigated in this study is that, for example, given an inspection strategy of two years and a desired life of 15 years, there is a 72% chance that the vessel will not experience enough partial damage‘ in the failure modes identified to constitute reaching the “end of structural life” as defined.
作者：
TODD, PPaul Todd
Ph.D. Director of the Bioprocessing and Pharmaceutical Research Center University City Science Center 3401 Market Street Suite 220 Philadelphia PA 19104.REFERENCES Universities Space Research Association Microgravity Biotechnology Working Group "Goals in Microgravity Biotechnology". 1985. Unpublished.Allen R.E. Rhodes P.H. Snyder R.S. Barlow G.H. Bier M. Bigazzi P.E. van Oss C.J. Knox R.J. Seaman G.V.F. Micale F.J. and Vanderhoff J.W. 1977. Column electrophoresis on the Apollo-Soyuz Test Project. Sep. Purif. Meth. 6: 1-59.|ISI|Snyder R.S. Rhodes P.H. Herren B.J. Miller R.Y. Seaman G.V.F. Todd P. Kunze M.E. and Sarnoff B.E. 1985. Analysis of free zone electrophoresis of fixed erythrocytes performed in microgravity. Electrophoresis 6: 3-9.|ISI|Tulp A. 1984. Density gradient electrophoresis of mammalian cells. In Methods of Biochemical Analysis 30: 148-198.Strickler A. and Sacks T. 1973. Continuous free-film electrophoresis: The crescent phenomenon. Prep. Biochem. 3: 269-277.|PubMed|ISI|ChemPort|Morrison D.R. Barlow G.H. Cleveland C. Grindeland R. Hymer W.C. Kunze M.E. Lanham J.W. Lewis M.L. Sarnoff B.E. Todd P. and Wilfinger W. 1984. Electrophoretic separation of kidney and pituitary cells on STS-8. Adv. Space Res. 4: 67-76.|Article|PubMed|ChemPort|Bier M. Palusinski O.A. Mosher R.A. and Saville D.A. 1983. Electrophoresis: Mathematical modeling and computer simulation. Science 219: 1281-1287.|PubMed|ISI|ChemPort|Albertsson P.A. 1971. Partition of Cell Particles and Macromolecules. Wiley- Interscience New York.Brooks D.E. and Bamberger S. 1982. Studies on aqueous two phase polymer systems useful for partitioning of biological material p. 233-240. In Materials Processing in the Reduced Gravity Environment of Space. G. E. Rindone (ed.) Elsevier Science Publ. Co. Inc. New York.Juarez-Salinas H. Engelhorn S.C. Bigbee W.L. Lowry M.A. and Stanker L.H. 1984. Ultrapurification of monoclonal antibodies by high-performanc
Since its inception in 1997, RoboCup has developed into a truly unique and long-standing research community advancing robotics and artificial intelligence through various challenges, benchmarks, and test fields. The m...
Since its inception in 1997, RoboCup has developed into a truly unique and long-standing research community advancing robotics and artificial intelligence through various challenges, benchmarks, and test fields. The main purposes of this article are to evaluate the research and development achievements so far and to identify new challenges and related new research issues. Unlike other robot competitions and research conferences, RoboCup eliminates the boundaries between pure research activities and the development of full system designs with hardware and software implementations at a site open to the public. It also creates specific scientific and technological research and development challenges to be addressed. In this article, we provide an overview of RoboCup, including its league structure and related research issues. We also review recent studies across several research categories to show how participants (called RoboCuppers) address the research and development challenges before, during, and after the annual competitions. Among the diversity of research issues, we highlight two unique aspects of the challenges: the platform design of the robots and the game evaluations. Both of these aspects contribute to solving the research and development challenges of RoboCup and verifying the results from a common perspective (i.e., a more objective view). Finally, we provide concluding remarks and discuss future research directions.
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