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Multiobjective antenna array design using the method of genetic algorithms

WSEAS Transactions on Communications 2005年第8期4卷 739-743页

作者： Mitilineos, Stelios A. Heretakis, Ioannis I. Chatziathanassiou, Nickolas Thomopoulos, Stelios C.A. Capsalis, Christos N. National Technical University of Athens Department of Electrical and Computer Engineering Division of Information Transmission Systems and Material Technology 9 Iroon Polytechneiou str. Athens 157 73 Greece National Center Science Research Demokritos Institute of Informatics and Telecommunications Patriarxou Ioakeim/Neapoleos str. Agia Paraskevi Athens 153 10 Greece

A multiobjective stochastic optimization technique is presented for the design of antenna arrays with given radiation pattern specifications. The technique utilizes the method of genetic algorithms and the proper objective functions are selected for the optimized array design. The technique has been implemented for the case where the arrays consist of vertical dipoles. The parameters of the GA include the elements positions, the array voltage excitation coefficients (amplitude and phase) and the radius and length of the dipoles. The array elements can either be arbitrarily placed, forming a non-uniform configuration or they can arange a circular, uniform, dual band array. In the latter case, the array and dipole characteristics are optimized by the GA for dual band operation, while different current coefficients have to be evaluated for each frequency. The presented results demonstrate the effectiveness, the versatility and applicability of the proposed technique.

关键词： Antenna arrays

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Tsunami monitoring system by stratospheric LTA platform

Tsunami monitoring system by stratospheric LTA platform

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AIAA 5th Aviation technology, Integration, and Operations Conference, ATIO and the AIAA 16th Lighter-than-Air systems technology Conference and Balloon systems Conference

作者： Koyama, Noboru Onda, Masahiko Sasaki, Yasunori Miura, Ryu Akinaga, Wakoto International Meteorological and Oceanographic Consultant Co. Ltd. Tokyo Japan National Institute of Advanced Industrial Science and Technology Tsukuba Ibaragi Japan National Defense Academy Yokosuka Kanagawa Japan National Institute of Information and Communications Technology Yokosuka Kanagawa Japan NEC Toshiba Space Systems Co. Ltd. Tokyo Japan Engineering Division Intelligent Systems Research Institute AIAA Department of Earth and Ocean Sciences Wireless Innovation System Group Sales and Marketing Division

ISBN: (纸本)1563477408

Tsunamis break out due to an oceanic earthquake or landslide and are propagated to far distant coasts at a very high speed resulting in serious damages to the coastal populations. This paper proposes a full-fledged advanced tsunami monitoring system which detects outbreaks of tsunamis and immediately disseminates alarm signals directly to the coastal populations from stationary LTA (Lighter-Than-Air) platforms positioned in the stratosphere over undersea epicenter areas. These platforms could also be used for other missions such as local weather observation, naval traffic monitoring etc., thus could be operated more economically than conventional tsunami monitoring and warning systems. Copyright © 2005 by the American institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： Tsunamis

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Cellular anisotropy in mechanical properties of polyurethane foam

Cellular anisotropy in mechanical properties of polyurethane...

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Society of Plastics Engineers Annual Technical Conference 2005, ANTEC 2005

作者： Goto, Akihiko Yamaguchl, Kazjjani Ishiaku, Umaru S. Hamada, Hiroyuki Department of Information Systems Engineering Osaka Sangyo University 3-1-1 Nakagaito Daito Osaka 574-8530 Japan Industrial Technology Center of Wakayama Prefecture 60 Ogura Wakayama 649-6261 Japan Division of Advanced Fibro Science Graduate School Kyoto Institute of Technology Sakyo-ku Kyoto 606-8585 Japan

We suggested that the cell shape in the polyurethane foam could be approximated to be the simple oval. We have investigated the relationship between the mechanical properties and the cell structure of the polyurethane foam. Deformation of cell structure was observed under the tensile load. Cellular anisotropy of the polyurethane was examined.

关键词： Foams

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Lunar contour crafting - A novel technique for ISRU-based habitat development

Lunar contour crafting - A novel technique for ISRU-based ha...

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43rd AIAA Aerospace sciences Meeting and Exhibit

作者： Khoshnevis, Behrokh Bodiford, Melanie P. Burks, Kevin H. Ethridge, Ed. Tucker, Dennis Kim, Won Toutanji, Houssam Fiske, Michael R. University of Southern California Information Sciences Institute Marina del Rey CA 90292 United States NASA/Marshall Space Flight Center Huntsville AL 35812 United States NASA/Jet Propulsion Laboratory Pasadena CA 91109 United States University of Alabama in Huntsville Huntsville AL 35899 United States Morgan Research Corporation Huntsville AL 35805 United States Department of Industrial and Systems Engineering United States Habitat Structures Technology Development/SY10 Systems Integration and Test Branch/EI52 Exploration Science and Technology Division Exploration Research Branch/XD42 Advanced Optical Concepts Division/XD31 Telerobotics Research and Applications Group Department of Civil and Environmental Engineering AIAA United States

As the nation prepares to return to the Moon, it is apparent that the viability of long duration visits with appropriate radiation shielding/crew protection, hinges on the development of Lunar structures, preferably in advance of a manned landing, and preferably utilizing in-situ resources. Contour Crafting is a USC-patented technique for automated development of terrestrial concrete-based structures. The process is relatively fast, completely automated, and supports the incorporation of various infrastructure elements such as plumbing and electrical wiring. This paper will present a conceptual design of a Lunar Contour Crafting system, designed to autonomously fabricate integrated structures on the Lunar surface using high-strength concrete based on Lunar regolith, including glass reinforcement rods or fibers fabricated from melted regolith. Design concepts will be presented, as well as results of initial tests aimed at concrete and glass production using Lunar regolith simulant. Key issues and concerns will be presented, along with design concepts for an LCC testbed to be developed at MSFC's Prototype Development Laboratory (PDL).

关键词： Moon

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Performance comparison of 802.16d OFDMA, TD-CDMA, cdma2000 1xEV-D0 and 802.11a WLAN on voice over IP service

Performance comparison of 802.16d OFDMA, TD-CDMA, cdma2000 1...

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IEEE Conference on Vehicular technology (VTC)

作者： Jee-young Song Hyun-ho Choi Hyun-dae Kim Sang-wook Kwon Dong-ho Cho Hong-sung Chang Geunwhi Lim Jun-hyung Kim Dept. EECS KAIST Guseong-dong Communication and Information Systems Lab Yuseong-gu Daejeon Republic of Korea Korea Advanced Institute of Science and Technology Daejeon Daejeon KR Dept. Electr. Eng. & Comput. Sci. KAIST Daejeon South Korea Department EECS Communication and Information Systems Laboratory Daejeon South Korea Telecommunication System Division Telecommunication Network Samsung Electronics Co. Ltd. Telecommunication System Division Telecommunication Network Samsung Electronics Co. Ltd. South Korea

We analyzed four systems designed for high-data rate transmission such as IEEE 802.16d OFDMA5 3GPP TD-CDMA, 3GPP2 cdma2000 1xEV-DO, and IEEE 802.11a WLAN, and compared their efficiency, the number of VoIP user, and the normalized number of VoIP user per 1 MHz. It is shown that the 802.16 system serves the most number of VoIP user, and the normalized number of user per 1 MHz is also the most. Even though 802.11a system is operated over the widest band, it supports the less number of user compared to the 802.16 system with smaller bandwidth, due to the inefficiency of CSMA/CA scheme. TD-CDMA and 1xEV-DO serve the same number of VoIP user per 1 MHz bandwidth, and TD-CDMA performs with the best efficiency among four systems. Comparing with TD-CDMA and 1xEV-DO, we concluded that 802.16d OFDMA system is the most flexible to assign its resource to users due to its finest granularity among three systems.

关键词： Wireless LAN Internet telephony Multiaccess communication Quadrature phase shift keying Bandwidth Wireless communication Time division multiple access Binary phase shift keying information systems Electronic mail

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Journal of information science and Engineering: Editorial notice

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Journal of information science and Engineering 2005年第5期21卷 i-ii页

作者： Lee, Der-Tsai Amato, Nancy M. Chang, Shih-Fu Chen, Homer H. Chen, Tsuhan Hsu, Tsan-Sheng Hwang, Jenq-Neng Kuo, Sy-Yen Kuo, Tei-Wei Li, Chung-Sheng Tokuyama, Takeshi Wing, Jeannette Wu, Tzong-Chen Yen, John Computer Science at Texas A and M University United States Parasol Laboratory United States IEEE Transactions on Parallel and Distributed Systems Computing Research Association's Committee on the Status of Women in Computing Research CRA-W's Distributed Mentor Program United States Department of Electrical Engineering Columbia University United States Lab. United States College of Electrical Engineering and Computer Science National Taiwan University Taiwan IEEE Transactions on Circuits and Systems for Video Technology IEEE Department of Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA United States ACM ACM SIGACT IEEE Computer Society IICM Austria Research and Development of the Department Multimedia Signal Processing Technical Committee IEEE Signal Processing Society United States IEEE Transactions on Circuits and systems for Video Technology College of Electrical Engineering and Computer Science National Taiwan Ocean University Keelung Taiwan Department of Electrical Engineering National Taiwan University Taiwan Department of Computer Science and Information Engineering National Taiwan University Taipei Taiwan IEEE Technical Committee on Real-Time Systems Computer Science Division IBM T.J. Watson Research Center United States IBM Research Division Graduate School of Information Sciences Tohoku University Japan ACM IPSJ Mathematical Society of Japan Japan Department of Computer Science Computer Science Department Carnegie Mellon University United States National Academies of Science's Computer Science and Telecommunications Board United States Microsoft's Trustworthy Academic Advisory Board Intel Research Pittsburgh's Advisory Board United States Dartmouth's Institute for Security Technology Studies Advisory Committee Canada Sloan Research Fellowships Program Committee United States ACM Taiwan China Information Sciences and Technology Pennsylvania State University United States Laboratory for Intelligent Agents Penn State's School of Info

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Constraint satisfaction problems and neurocomputing

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International Congress Series 2004年第C期1269卷 161-164页

作者： Nagamatu, Masahiro Nakano, Takahiro Zhang, Kairong Division of Neural Information Processing Department of Brain Science and Engineering Graduate School of Life Science and Systems Engineering Kyushu Institute of Technology 2-4 Hibikino Wakamatsu Kitakyushu Fukuoka 808-0196 Japan

CSP is an important problem in computer science. However, the CSP is also a well-known NP-complete problem. Local search, which is a representative of incomplete methods, can usually find a solution considerably faster than complete methods. However, the local search has a serious drawback of being trapped by local minima. We proposed a neural network called Lagrange programming neural network with polarized high-order connection (LPPH) for SAT. The LPPH solves a problem called CONSAT, which is a continuous valued variant of the SAT. Experimental results show that the LPPH can find the solution effectively without using any stochastic moves or multiple restarts. In this paper, we propose an extension of the LPPH called LPPH-CSP for solving the CSP. We show the effectiveness of the LPPH-CSP through experiments. The LPPH(-CSP) can update the values of all variables simultaneously. This is an advantage for VLSI implementation. The LPPH(-CSP) is also very flexible and robust to deal with uncertainty or errors included in the problem specifications or requirements for solutions. We think these properties are very useful for brain-like computing and its hardware realization. © 2004, Elsevier Inc. All rights reserved.

关键词： Constraint satisfaction Lagrangian method Local minima Neurocomputing Satisfiability problem VLSI implementation

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Intelligent vehicle airbag controller design

Intelligent vehicle airbag controller design

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IEEE Conference on Cybernetics and Intelligent systems

作者： Yi-Jen Mon Kuang-Tso Luo Department of Computer Science and Information Engineering Chung-Kuo Institute of Technology Hsinchu Taiwan Division of Electronic Systems Chung Shang Institute of Science and Technology Taoyuan Taiwan

ISBN: (纸本)0780386434

An intelligent vehicle airbag controller design methodology is proposed in this paper. Firstly, the vehicle impact severity is analyzed to get four characteristic factors utilized as fuzzy inputs. From these four characteristics factors, the 'two stages fuzzy algorithm' is developed and used as the airbag deployment algorithm to identify the vehicle impact severity. Finally, the fuzzy-Gaussian neural network (FGNN) is used to train the suitable fuzzy membership functions and fuzzy rules based on this proposed 'two stages fuzzy algorithm'. Simulation results for different vehicle crash data demonstrate the validity and effectiveness of the proposed design methodology

关键词： Intelligent vehicles Fuzzy neural networks Vehicle crash testing Neural networks Acceleration Algorithm design and analysis Sensor systems Prediction algorithms Fuzzy systems Design methodology

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Non-monotonic reasoning in prioritized knowledge bases based on granular reasoning

Non-monotonic reasoning in prioritized knowledge bases based...

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IEEE International Conference on Fuzzy systems (FUZZ-IEEE)

作者： Y. Kudo T. Murai Department of Computer Science and Systems Engineering Muroran Institute of Technology Muroran Japan Division of Computer Science Graduate School of Information Science and Technology Hokkaido University Sapporo Japan

We propose a method of semantically nonmonotonic reasoning in prioritized knowledge bases based on incomplete information systems and granular reasoning. Our nonmonotonic reasoning is characterized as "reasoning with disregard of difference of detail." We provide granularized models and priority of each rule, and formulate the method of semantically non-monotonic reasoning based on the idea of ignored sets, rejected sets and possible tuples of atomic sentences that we propose.

关键词： information systems Null value Computer science Set theory Knowledge engineering systems engineering and theory information science Multivalued logic Rough sets

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Classification of atrial tachyarrhythmias in electrocardiograms using time frequency analysis

Classification of atrial tachyarrhythmias in electrocardiogr...

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Computers in Cardiology 2004

作者： Tsipouras, M.G. Oikonomou, V.P. Fotiadis, D.I. Michails, L.K. Sideris, D. Unit of Medical Technology and Intelligent Information Systems Department of Computer Science University of Ioannina GR 45110 Ioannina Greece Biomedical Research Institute FORTH GR 45110 Ioannina Greece Michaelidion Cardiology Center GR 45110 Ioannina Greece Division of Cardiology Medical School GR 45110 Ioannina Greece Unit of Medical Technology and Intelligent Information Systems Dept. of Computer Science University of Ioannina Campus P.O. BOX 1186 GR 45110 Ioannina Greece

In this work a novel automated method, combining time-frequency analysis and expert's knowledge, for the classification of atrial tachyarrhythmias is presented. It is based on the analysis of small ECG segments and their classification into three categories of cardiac rhythm: (a) atrial fibrillation, (b) atrial flutter and (c) normal sinus rhythms. Time-frequency analysis is used to calculate the power spectrum density for each segment. Several spectral characteristics are extracted from the power spectrum density, representing the energy distribution on the time-frequency plane. These characteristics are used as input in an artificial neural network, which classifies each ECG segment into one of the three categories. The method is validated using the MIT-BIH arrhythmia database and the obtained average sensitivity and specificity are 93.4% and 96.5%, respectively. © 2004 IEEE.

关键词： Electrocardiography

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