The advantages of single electron devices with asymmetrical tunnel barriers (ATBs), proposed by the authors, over conventional single electron devices with symmetrical tunnel barriers (STBs) are discussed by referring...
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The advantages of single electron devices with asymmetrical tunnel barriers (ATBs), proposed by the authors, over conventional single electron devices with symmetrical tunnel barriers (STBs) are discussed by referring to the features of ATBs and the results of computer simulation of the performance of tunnel-junction-load SET logic and turnstile devices. Experimental observation of a Coulomb staircase and asymmetrical tunnel characteristics in ATBs fabricated with GaAs/AlGaAs heterostructures are also reported.
作者:
Ishiba, KKomatsu, TTakahara, MFaculty of Engineering
Yamanashi University Kofu Japan 400 Graduated in 1994 from the Department of Electronic and Information Engineering
where he is currently in the Master's program. He has been engaged in research on optical fiber soliton transmission. Received his B.S. and M.S. degrees in 1993 and 1995
respectively from the Department of Electronic and Information Engineering Yamanashi University. He joined NTT in April 1995. He has been engaged in research on simulation of the optical fiber soliton transmission and on the transmission system with flexibility in transmission speed. Graduated from the Department of Electrical Engineering
Yamanashi University in 1965 and received his M.S. degree in 1967. He received his Ph.D. degree later. In 1967 he became a Research Associate of the Department of Electronic Engineering Yamanashi University. In 1991 he became a Professor of Electronic and Information Engineering. He has been engaged in research on special function theory nonlinear circuits optical communication systems and LAN systems. In 1984 he received a Book Award from I.E.I.C.E. In 1990–91 he was on leave at Southampton University. He is a member of IEEE.
In the development of practical multimedia systems, greater capacity is desired in a long-distance large-capacity transmission system. A number of studies have been undertaken to develop a long-distance large-capacity...
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In the development of practical multimedia systems, greater capacity is desired in a long-distance large-capacity transmission system. A number of studies have been undertaken to develop a long-distance large-capacity system. Several long-distance transmission experiments for high-density transmission by wavelength demultiplexing method (WDM) have been reported recently. However, more of the experimental examples have reported on soliton transmission than on WDM systems. Hence, the former is considered more advanced. It is necessary to prepare a fiber of a length of approximately 10,000 km for ultralong-distance transmission experiment. Since this is difficult to obtain, repetitive experiments are often the case. However, such an experiment does not disclose the effects of dispersion and loss fluctuation in the fiber. In this paper, the effect of fluctuation in dispersion and loss in the fiber is studied by simulation so that the resilience of the soliton to the variations of the fiber characteristics is evaluated.
作者:
Okano, KHigashino, TTaniguchi, KMemberFaculty of Engineering Science
Osaka University Toyonaka Japan 560 Teruo Hipshino received his B.E.
M.E.and Ph.D. degrees in Information and Computer Sciences from Osaka University Osaka Japan in 1R9 1981 and 1984 respectively. He joined the Faculty of Osaka University in 1984. Since 1991 he has been an Associate Professor in the Department of Information and Computer Sciences at Osaka University. In 1990 he was a Visiting Researcher of Dept. I.R.O. at University of Montreal Canada. His current research interests include design and analysis of distributed systems specification and verification of communication protocols and formal approach of program design. He is a member of IEEE-CS ACMIEICE of Japanand IPS of Japan.
In this paper, new methods for providing the correctness of refinement among abstract sequential machine style programs are described. The programs are described in algebraic language ASL using some useful notions, i....
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In this paper, new methods for providing the correctness of refinement among abstract sequential machine style programs are described. The programs are described in algebraic language ASL using some useful notions, i.e., the extended projection and the valid reachability condition for each transition function. These notions allow a designer to refine a given text (program or specification) to a concrete text more freely than the text that does not use such notions. These notions can also enhance the expressive power of the text. On the other hand, these advantages would have lost half their values, if useful methods to prove the correctness of refinement among the texts using them are not found. Thus new methods for proving the correctness of the texts are proposed, and they do not require much proof loads. First, the correctness of refinement among the ASL texts with the extended projection is defined. Second, a method is proposed for proving the correctness of refinement among such texts. Also proposed is a definition of the correctness of refinement among the texts with the valid reachability conditions and a method to prove their correctness. These methods do not require more proof loads than the usual methods for the texts that do not use such notions in the abstract sequential machine style. Therefore, these methods are useful.
作者:
Tsuji, YKoshiba, MTanabe, TFaculty of Engineering
Hokkaido University Sapporo Japan 060 Graduated in 1991 from the Department of Electronic Engineering
Hokkaido University and received his M.S. degree in 1993. He is currently working toward a doctoral degree. He has been engaged in research on the computer-aided design of optical and quantum-wave phenomena and quantum-effect devices. Graduated in 1971 from the Department of Electronic Engineering
Hokkaido University and received his M.S. and Dr. of Eng. degree in 1973 and 1976 respectively. In 1976 he became a Lecturer at Kitami Institute of Technology where he was promoted to an Associate Professor in 1977. In 1979 he became an Associate Professor in the Department of Electronic Engineering Hokkaido University where he was promoted to Professor in 1987. He has been engaged in research on opto- and wave-electronics. In 1987 he received a Best Paper Award. He is the author ofFoundations of Finite Element Method for Opto- and Wave-Electronics(Morikita Publ.)Optical Waveguide Analysis(Asakura Publ.)Optical Waveguide Analysis(McGraw-Hill Book Co.) andOptical Waveguide Theory by the Finite Element Method(KTK Scientific Publishers/Kluwer Academic Publishers). He has co-authored one book and written Graduated in 1995 from the Department of Electronic Engineering
Hokkaido University and is currently in the Master's program. He has been engaged in research on opto- and wave-electronics.
To the best of the knowledge of the authors, the formulation is carried out for the first time on the finite-element beam-propagation method for the analysis of the magnetooptic waveguide in which the structure varies...
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To the best of the knowledge of the authors, the formulation is carried out for the first time on the finite-element beam-propagation method for the analysis of the magnetooptic waveguide in which the structure varies along the propagation direction. The present method is applicable not only to the case in which refractive index difference is small but also to the case for the TE mode and the TM mode propagating in a waveguide with a large refractive index difference. To suppress the spurious reflection from the computational window edges, the transparent boundary condition is applied.
作者:
Aoki, YIijima, TMemberJapan Advanced Institute of Science and Technology
Hokuriku Ishikawa Japan 923 Yasubim Aoki:graduated from the University of Kanazawa Faculty of Engineering
Department of Electrical Engineering and Information Science in 1992 and received his Master's degree in 1994 from the Japan Advanced Institute of Science and Technology Hokuriku Department of Information Science where he is currently in the doctoral program engaged in research on pattern recognition. Honorary MemberTaizo lijima:graduatedwith a B.E. degree from the Tokyo Institute of Technology in 1948 and received his Ph.D. degree later. He joined the Electro-Technical Laboratories in 1948 and
since then has been involved in research on electromagnetic theory and pattern recognition theory image processing voice recognition and research and development of OCR. After serving as the head of Iijima Special Research Laboratories he became Professor at the Tokyo Institute of Technology in 1986. He because Professor Emeritus of that institute in 1986. He became Professor at Tokyo Engineering University and Professor Emeritus there in 1991. In 1991 he became Professor at the Japan Advanced Institute of Science and Technology and was appointed Vice President of the institute in 1992. He served successively as editor examiner secretary of general affairs inspector counsel committee-head of pattern recognition and specialized studies head of Tokyo chapter and vice president of this institute. In 1991 he became Honorary Member. He received the Paper Award from the Institute four times and the Literary Works Award once. He received the Achievement Award and the Distinguished Service Award in 1976 and 1989 respectively. He received the Purple Ribbon Medal from the Emperor in 1989.
Theoretical studies on Iijima's ''Theory of Pattern Recognition,'' which is known as a method of multiple similarity, have shown clearly that there are situations when it is difficult to determine ...
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Theoretical studies on Iijima's ''Theory of Pattern Recognition,'' which is known as a method of multiple similarity, have shown clearly that there are situations when it is difficult to determine the viewpoint and visual field, important parameters to introduce topological aspects into the pattern space, observing a figure itself. To cope with this problem, this paper proposes transforming the observed image from a figure f(r) to a second-order differential image rho(r), called ''figure source.'' The aim is to reconstruct the theory in such a way as to enable the application of similarity evaluation methods as in the conventional case, without compromising the current theory, and all the necessary proofs are given. In this paper, the figure source equation as well as rules representing its properties are developed, and several related physical quantities are redefined.
The subband adaptive system, where the idea of the filter bank is applied to the adaptive filter, has a feature that a higher-order adaptation can be reduced to lower-order adaptations. The reduction of the order of t...
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The subband adaptive system, where the idea of the filter bank is applied to the adaptive filter, has a feature that a higher-order adaptation can be reduced to lower-order adaptations. The reduction of the order of the adaptive filter is related closely to the number of channels and the decimation ratio. The order of adaptive digital filter (ADF) is decreased greatly when the number of subbands is increased, and the decimation ratio is increased up to the maximum value. Then, however, the number of coefficient-updates per unit time is decreased, which results in the deterioration of the convergence Speed. From such a viewpoint, this paper discusses a method to improve the convergence speed, which is deteriorated in the subband adaptive system, due to the decimation. The idea of the proposed method is to utilize effectively the data which have been discarded in the decimation process and to improve the convergence speed. It is called the multirate repeating method. As the first step, the multirate repeating method is applied to the conventional subband adaptive system and the convergence speed is improved. Then a subband adaptive system is introduced in which the multirate repeating method can be utilized more effectively. As a result, a faster convergence is realized while retaining the ADF order-reduction effect, which is an advantage of the subband adaptive system.
作者:
DeHaemer, DJDr. Michael J. DeHaemer:is Director of the World Technology Evaluation Center and the Japanese Technology Evaluation Center at Loyola College in Baltimore. He has directed more than a dozen studies of technologies in foreign countries under the sponsorship of the National Science Foundation
ARPA Departments of Energy and Commerce and other agencies. He has a continuing interest in assessing foreign technologies in comparison to the United States.—-On the faculty of the Sellinger School of Business at Loyola College Dr. DeHaemer is a former department chairman and an associate professor of information systems and decision sciences. He teaches the strategic use of information technology and human-computer interface design. His research includes user performance with automated speech recognition systems for computers and business applications of artificial intelligence. Dr. DeHaemer completed an earlier career as a submarine officer including command of a ballistic missile submarine. He holds a B.S. degree from the University of Notre Dame and a Master's degree in Operations Analysis from the Naval Postgraduate School. He has an M.B.A. an M.S. in Industrial Engineering and a Ph.D. in Management Information Systems from Rensselaer Polytechnic Institute.
A team of experts, assembled by the World Technology Evaluation Center, visited twenty-five locations in Russia and Ukraine to observe the state of undersea technologies. Academic sites, basic research institutes, ind...
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A team of experts, assembled by the World Technology Evaluation Center, visited twenty-five locations in Russia and Ukraine to observe the state of undersea technologies. Academic sites, basic research institutes, industrial development laboratories, and oceanographic operating bases were visited. The report highlights specific technologies that support research submersibles;and critiques the strengths and weaknesses of the ocean technologies establishment. Russia and Ukraine were found to have a number of strengths, especially in test facilities, a large fleet of surface and submersible research vessels, and highly educated and qualified engineers and scientists. Although political and economic conditions need to be over-come, there is motivation for many cooperative commercial or research ventures with both government institutes and new private companies in Russia and Ukraine.
作者:
RYAN, JCJONS, OPJ. Christopher Ryan:earned his bachelor's and master's degrees in Naval Architecture from Webb Institute and MIT
respectively. He spent three years at the Advanced Marine Technology Division of Litton Industries working on the DD-963 class ship design and related computer aided design projects. he subsequently went to the Navy Department concentrating on early stage design of surface combatants for 12 years including work on the FFG-7 Sea Control Ship CSGN and CVV aircraft carrier projects. He then shifted focus and became the technical director for the Computer Supported Design Program in NavSea for five years. Mr. Ryan has served in several supervisory positions within the Ship Design Group in NavSea since that time. He is currently the project manager for the Ship Design Acquisition and Construction Process Improvement Project. Otto P. Jons:received a Diplom Ing. in shipbuilding from the Technical University of Hannover
W. Germany and an M.S. in naval architecture and marine engineering from the Massachusetts Institute of Technology in 1967. He then joined Litton Ship Systems where he was responsible for the preliminary design of the DD-963 hull structure and then for ship systems as manager LHA Ship Systems Engineering Department. From 1972 to 1974 he was principal research scientist at Hydronautics. In 1976 as technical director he helped establish the local office of Designers and Planners. Otto Jons was one of the co-founders of Advanced Marine Enterprises Inc. in 1976 where he is corporate vice president engineering.
In the spring of 1990, the NavSea Chief Engineer initiated a project to improve the design, acquisition and construction (DAC) of U.S. Navy ships. The project's objectives are to reduce the time and cost of acquir...
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In the spring of 1990, the NavSea Chief Engineer initiated a project to improve the design, acquisition and construction (DAC) of U.S. Navy ships. The project's objectives are to reduce the time and cost of acquiring and operating Navy ships while improving their quality, unlike previous studies on the subject, the project utilizes a rigorous process analysis approach and attempts to use quantitative measures as the basis for recommending improvements. The paper is, of necessity, a status report on the progress of this project. Topics covered include: the DAC process;a look at the current state of ship acquisition time, cost, and quality;the methodology for process improvements;and early findings.
作者:
VINROOT, CAORNER, JGUSNCapt. Charles A. Vinroot
USN (Ret.)retired from the U.S. Navy in September 1991 following over 27 years of active duty as an engineering duty officer. He holds a BSEE from North Carolina State University and a MSEE and professional degree from the U.S. Naval Postgraduate School. During his naval career he served on USSIndependence (CVA-62) and USSLuce (DLC-7/DDC-38). He also served at Supship Quincy Mass. and Hunters Point Naval Shipyard. He was stationed in Washington D.C. with assignments at CNO (OP 98) ASN (S&L) and the Naval Sea Systems Command. Captain Vinroot was technical director of the Battleship Reactivation Program (PMS 378) technical director of the Destroyer Acquisition Program (PMS 389) and deputy program manager of the Amphibious Warfare and Strategic Sealift Program (PMS 377). Most recently he served as program manager for Gas Turbine Surface Combatants (PMS 314) and Surface Combatants (PMS 330). Captain Vinroot is now employed by PRC Inc. and serves as technical director for the Advanced Technology Division in Crystal City Va. Jeffery G. Ornergraduated from Wittenberg University in Springfield
Ohio in 1979 with a bachelor of arts degree in political science and earned a master's of science degree in business from The American University in Washington D.C. in 1982. He has ten years of professional experience with the Naval Sea Systems Command in positions with responsibilities for logistic support planning policy and delivery computer-aided acquisition and logistic support and Fleet Modernization Program (FMP) and ship construction issues. He was a key player in establishing the current FMP integrated logistic support (ILS) process and in implementing of the Ships' Configuration and Logistic Support Information System (SCLSIS). His current position as Fleet Logistic Support Branch head for the Surface Combatant Program includes responsibility for logistic support and management of ship configuration and logistic data for all surface combatant ships (except for Aegis ships). In
USS Ingraham (FFG-61) is the prototype ship for NavSea's Advanced Technical information System (ATIS). ATIS is a digital technical library, which holds on optical disks the ship's 2,000 technical manuals and 7...
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USS Ingraham (FFG-61) is the prototype ship for NavSea's Advanced Technical information System (ATIS). ATIS is a digital technical library, which holds on optical disks the ship's 2,000 technical manuals and 73,000 drawing sheets. It contains a detailed ship's configuration index (derived from SCLSIS) to lead the user to the proper drawing or manual, and it replaces the ship's aperture cards and the second (library) copy of the technical manuals. ATIS, and the data standards established and tested through ATIS development, will be the technical library portion of micro-SNAP and SNAP III. It also forms an important part of NavSea's plans to utilize EDMICS data. This paper describes the goals and technical concepts behind the development of ATIS. Problems encountered, solutions developed, and lessons learned are detailed. Special attention was paid to the application of the computer Aided Acquisition and Logistic Support (CALS) standards, problems caused by conflicts and ambiguities in those standards, the standards. Original program goals are compared with actual operational experiences. Plans for future expansion are outlined, including applications of this technology in the availability planning and execution process. A comparison is developed among the various methods of optical imaging and their costs and benefits.
作者:
OSTENDORF, DWLEACH, LEHINLEIN, ESXIE, YF1 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 fie...
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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