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GLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference

作者： Yao Ma Alex Leith Mohamed-Slim Alouini Xuemin Shen Department of Electrical and Computer Engineering Iowa State University Ames IA USA King Abdullah University for Science and Technology Thuwal Saudi Arabia Department of Electrical and Computer Engineering University of Waterloo Waterloo ONT Canada

In this paper, we study the sum rate maximization algorithms with long-term proportional rate fairness (PRF) for uplink orthogonal frequency division multiple access (OFDMA) systems. In contrast to the rate-maximization schemes which used short-term PRF in the literature, we propose to use a selective multiuser diversity (SMuD) scheme to achieve a long-term PRF and improved sum rate performance. This scheme implements weighted channel signal-to-noise ratio (w-SNR)-based ranking for user selection on each subchannel, and then uses either water-filling (WF) or equal power allocation (EPA) along the assigned channels of each user. Both offline and online methods to find the optimal SNR weight factors are designed to achieve the target proportional rates for different users. The offline optimization technique requires to know the channel distribution information (CDI) at the scheduler. The online method uses the weight adaption combined with individual user rate tracking, which avoids the need to know the CDI. Analytical throughput metrics for the proposed w-SNR scheme with WF and EPA over Rayleigh channels are derived, and verified by simulations. Simulation results show that the proposed w-SNR PRF scheme can achieve significantly higher sum rates than the frequency diversity-based short-term and long-term fairness schemes. Besides the improved performance, the proposed schemes have a low complexity which is linear to numbers of users and subchannels.

关键词： Quality of service Diversity methods Scheduling algorithm Frequency conversion Signal to noise ratio Target tracking Throughput Downlink Convergence Dynamic scheduling

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Enhanced terahertz detection using multiple GaAs HEMTs connected in series

Enhanced terahertz detection using multiple GaAs HEMTs conne...

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Microwave, MTT-S International Symposium

作者： Tamer A. Elkhatib Dmitry B. Veksler Khaled N. Salama Xi-C. Zhang Michael S. Shur Center for Terahertz Research Rensselaer Polytechnic Institute Troy NY USA Electrical Engineering Program King Abdullah University for Science and Technology Saudi Arabia

We report here, for the first time, on enhanced nonresonant detection of terahertz radiation using multiple InGaAs/GaAs high-electron-mobility transistors (HEMTs) connected in series and biased by a direct drain current. A 1.63 THz (184 mum) response is proportional to the number of detecting transistors operating in saturation region at the same gate-source bias voltage. The experimental data are in agreement with the detection mechanism based on the rectification of overdamped plasma waves excited by radiation in channels of devices.

关键词： Gallium arsenide HEMTs MODFETs Plasma waves Testing Submillimeter wave technology Gas lasers Optical imaging Radiation detectors Indium gallium arsenide

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An Implementation of Traffic Light System Using Multi-hop Ad hoc Networks

An Implementation of Traffic Light System Using Multi-hop Ad...

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International Conference on Network-Based Information Systems (NBIS)

作者： Imran Shafique Ansari Computer Engineering Department King Fahd University of Petroleum and Minerals Dhahran Saudi Arabia Computer Engineering Department King Abdullah University for Science and Technology Dhahran Saudi Arabia

In ad hoc networks nodes cooperate with each other to form a temporary network without the aid of any centralized administration. No wired base station or infrastructure is supported, and each host communicates via radio packets. Each host must act as a router, since routes are mostly multi-hop, due to the limited power transmission set by government agencies, (e.g. the Federal Communication Commission) (FCC), which is 1 Watt in Industrial Scientific and Medical (ISM) band. The natures of wireless mobile ad hoc networks depend on batteries or other fatiguing means for their energy. A limited energy capacity may be the most significant performance constraint. Therefore, radio resource and power management is an important issue of any wireless network. In this paper, a design for traffic light system employing ad hoc networks is proposed. The traffic light system runs automatically based on signals sent through a multi-hop ad hoc network of `n' number of nodes utilizing the Token Ring protocol, which is efficient for this application from the energy prospective. The experiment consists of a graphical user interface that simulates the traffic lights and laptops (which have wireless network adapters) are used to run the graphical user interface and are responsible for setting up the ad hoc network between them. The traffic light system has been implemented utilizing A Mesh Driver (which allows for more than one wireless device to be connected simultaneously) and Java-based client-server programs.

关键词： Telecommunication traffic Spread spectrum communication Ad hoc networks Traffic control FCC Graphical user interfaces Base stations Power transmission US Government Communication industry

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A CalderÓn Multiplicative Preconditioner for the Combined Field Integral Equation

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IEEE Transactions on Antennas and Propagation 2009年第10期57卷 3387-3392页

作者： Hakan Bagci Francesco P. Andriulli Kristof Cools Femke Olyslager Eric Michielssen Department of Electrical Engineering and Computer Science University of Michigan Ann Arbor MI USA Division of Physical Sciences and Engineering King Abdullah University of Science and Technology Thuwal Saudi Arabia Electronics Department Politecnico di Torino Torino Italy Electromagnetics Group Ghent University Ghent Belgium

A Calderon multiplicative preconditioner (CMP) for the combined field integral equation (CFIE) is developed. Just like with previously proposed Calderon-preconditioned CFIEs, a localization procedure is employed to ensure that the equation is resonance-free. The iterative solution of the linear system of equations obtained via the CMP-based discretization of the CFIE converges rapidly regardless of the discretization density and the frequency of excitation.

关键词： Integral equations Magnetic fields Information technology Magnetic resonance Linear systems Frequency Electromagnetic analysis Magnetic analysis Electromagnetic scattering Electromagnetic radiation

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A design of a class of temperature stabilization system and implementation

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WSEAS Transactions on Circuits and Systems 2009年第6期8卷 498-507页

作者： Lin, Shieh-Shing Horng, Shih-Cheng Hsu, Hen-Chia Chen, Jia-Hau Hsieh, Tseng-Lin Ho, Chih-Hao Lin, Kuang-Yao Department of Electrical Engineering St. John's University Tam King Road Tamsui Taiwan Department of Computer Science and Information Engineering Chaoyang University of Technology Taichung Taiwan

In this paper, we proposed a design for a class of temperature stabilization system based on the feedback control theory and the corresponding technology of microchip MC89C51 and sensors theory. Besides, the proposed design was implemented on a set of temperature control system to determine whether the current status of fishes tank fitting fishes survival or not. Therefore, we can control the temperature of fishes tank. There are three stages in this design. First, we set the temperatures at the fish tank harming fishes life are not suitable for the safety status. Second, we use the MC89C51microprocessor combined with the A/D converter to process the analog measuring temperatures of the sensor measurements into digital data. Finally, a software program was designed to process the obtained digital data and control the solid-state electric relay to increase or decrease the target temperature of the water tank.

关键词： Stabilization

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The effect of multi active junctions on broadband emission from InAs/InGaAlAs quantum-dash structure

The effect of multi active junctions on broadband emission f...

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IEEE Photonics Conference (IPC)

作者： C. L. Tan H. S. Djie C. K. Tan V. Hongpinyo Y. H. Ding B. S. Ooi Center for Optical Technologies and Department of Electrical and Computer Engineering Lehigh University Bethlehem PA USA JDS Uniphase Corporation San Jose CA USA Department of Electronic and Electrical Engineering University of Sheffield Sheffield UK Division of Physical and Chemical Science and Engineering King Abdullah University for Science and Technology Thuwal Saudi Arabia

We demonstrate the importance of multi active layer stacking in realizing a semiconductor broadband quantum-dash-in-well laser. The photoluminescence measurements show the negligible factor of largely localized inhomo... 详细信息

ISBN: (纸本)9781424436804

关键词： Chemical lasers Semiconductor lasers Quantum computing Chemical technology Fiber lasers Gas lasers Photoluminescence Biomedical measurements Extraterrestrial measurements Optical fiber dispersion

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A noble Heuristic reading device for blind people

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WSEAS Transactions on Systems 2009年第6期8卷 703-712页

作者： Lin, Shieh-Shing Lee, king-Tan Horng, Shih-Cheng Lin, Kuang-Yao Hsieh, Tseng-Lin Chien, Jia-Hau Hsu, Hen-Chia Department of Electrical Engineering St. John's University 499 Sec. 4 Tam King Road Tamsui Taiwan Department of Engineering Lee-Ming Institute of Technology Taipei Taiwan Department of Computer Science and Information Engineering Chaoyang University of Technology Taichung Taiwan

In this paper, the authors present a noble heuristic reading machine for blind people. The goal of this paper is to use intelligent-control method to settle down the reading machine by a touch-pat device for blind people. The proposed "A noble heuristic reading device for blind people" can efficiently help blind people for reading and train the blind people learning the dot-touched words as well. First of all, the feedback control theorem associated with some sensors is used to accomplish the action of automatic fixed position of the reading machine. Second, a heuristic program used to analyze a certain word by converting dot-touched signals into meaningful code will transfer word-code into phonetic signals and speak out for blind people effectively and precisely through personal computer interface. There are three units in the proposed design, which includes the hardware structure, the analysis for certain word-meaning and the phonetic output of the specified words. The test results show that the proposed smart reading machine can effectively prompt learning and reading effects for blind people.

关键词： Feedback control

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ROLE OF SIMULATION IN RAPID PROTOTYPING FOR CONCEPT DEVELOPMENT

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NAVAL ENGINEERS JOURNAL 1991年第3期103卷 204-211页

作者： king, JF BARTON, DE J. Fred King:is the manager of the Advanced Technology Department for Unisys in Reston Virginia. He earned his Ph.D. in mathematics from the University of Houston in 1977. He has been principal investigator of research projects in knowledge engineering pattern recognition and heuristic problem-solving. Efforts include the development of a multi-temporal multispectral classifier for identifying graincrops using LANDSAT satellite imagery data for NASA. Also as a member of the research team for a NCI study with Baylor College of Medicine and NASA he helped develop techniques for detection of carcinoma using multispectral microphotometer scans of lung tissue. He established and became technical director of the AI Laboratory for Ford Aerospace where he developed expert scheduling modeling and knowledge acquisition systems for NASA. Since joining Unisys in 1985 he has led the development of object-oriented programming environments blackboard architectures data fusion techniques using neural networks and intelligent data base systems. Douglas E. Barton:is manager of Logistics Information Systems for Unisys in Reston Virginia. He earned his B.A. degree in computer science from the College of William and Mary in 1978 and did postgraduate work in London as a Drapers Company scholar. Since joining Unisys in 1981 his work has concentrated on program management and software engineering of large scale data base management systems and design and implementation of knowledge-based systems in planning and logistics. As chairman of the Logistics Data Subcommittee of the National Security Industrial Association (NSIA) he led an industry initiative which examined concepts in knowledge-based systems in military logistics. His responsibilities also include evaluation development and tailoring of software engineering standards and procedures for data base and knowledge-based systems. He is currently program manager of the Navigation Information Management System which provides support to the Fleet Ballistic Missile Progr

A valuable technique during concept development is rapid prototyping of software for key design components. This approach is particularly useful when the optimum design approach is not readily apparent or several known alternatives need to be rapidly evaluated. A problem inherent in rapid prototyping is the lack of a "target system" with which to interface. Some alternatives are to develop test driver libraries, integrate the prototype with an existing working simulator, or build one for the specific problem. This paper presents a unique approach to concept development using rapid prototyping for concept development and scenario-based simulation for concept verification. The rapid prototyping environment, derived from artificial intelligence technology, is based on a blackboard architecture. The rapid prototype simulation capability is provided through an object-oriented modeling environment. It is shown how both simulation and blackboard technologies are used collectively to rapidly gain insight into a tenacious problem. A specific example will be discussed where this approach was used to evolve the logic of a mission controller for an autonomous underwater vehicle.

关键词： Military engineering

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Abstracts

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Environmental Management 1977年第1期1卷 67-96页

作者： Frankenfeld, John W. Schulz, Wolfgang McMurty, George J. Petersen, Gary W. May, G. A. Hering, F. S. Schwartz, J. I. Heywood, J. B. Chigier, N. A. Grohse, E. W. Walker, J. D. Colwell, R. R. Petrakis, L. Pergament, H. S. Thorpe, R. D. Schoepf, Richard W. Krzyczkowski, Roman Henneman, Suzanne S. Hudson, Charles L. Putnam, Evelyn S. Thiesen, Donna J. Parks, G. A. McCarty, Perry L. Leckie, J. O. Schrumpf, Barry J. Simonson, G. H. Paine, D. P. Lawrence, R. D. Pyott, W. T. Leh, M. Elders, W. Combs, J. Caplen, T. Harrison, F. L. Wong, K. M. Heft., R. E. Charnell, Robert L. Lehmann, Edward J. Mallon, Lawrence G. Hatfield, Cecile Adams, Gerald H. Johanning, James Talvitie, Antti Noll, Kenneth E. Miller, Terry Smiarowski, Joseph F. Willis, Cleve E. Foster, John H. Schlesinger, Benjamin Daetz, Douglas Lear, Donald U. Smith, Mona F. Hundemann, Audrey S. Crockett, Pernell W. Werner, Kirk G. Carroll, Thomas E. Maase, David L. Genco, Joseph E. Ifeadi, Christopher N. Lowman, F. G. Christensen, S. W. Van Winkle, W. Mattice, J. S. Harrison, Elizabeth A. Barker, James C. Chesness, Jerry L. Smith, Ralph E. Shaheeen, Donald G. Raney, R. Keith Borton, T. Wezernak, C. T. Raney, R. K. Sherwani, Jabbor K. Moreau, David H. Eisenberg, Norman A. Lynch, Cornelius J. Breeding, Roger J. Johnson, J. D. Foster, K. E. Mouat, D. A. Clark, R. Hyden, John William Owen, Wilfred Bayfield, Neil G. Barrow, Graham C. Stolz, Stephanie B. Wienckowski, Louis A. Brown, Betram S. Keyfitz, Nathan Wilson, W. L. Newman, Peter W. G. Bammi, Deepak Bammi, Dalip Goddard, James E. Chisholm, Tony Walsh, Cliff Brennan, Geoffrey Thompson, K. S. Richardson, R. Jensen, Clayton E. Brown, Dail W. Mirabito, John A. Cowing, Thomas G. Binghamton, Suny Siehl, George H. Albrecht, O. W. Alexander, Ariel Barde, Jean -Philippe Darby, William P. McMichael, Francis Clay Dunlap, Robert W. Muckleston, Keith W. Frankenhoff, Charles A. Giulini, Lorenzo T. Wyatt, T. Black, Peter E. Keating, William Thomas Leonard, M. E. Fisher, E. L. Brunelle, M. F. Dickinson, J. E. Pethig, Rudiger Clapham Exxon Research & Engineering Co. Linden Government Research Lab Coast Guard Washington D.C. Department of Transportation Washington D.C. Office For Remote Sensing of Earth Resources. NASA Earth Resources Survey Program Pennsylvania State University Washington D.C. Department of the Navy Washington D.C. Cambridge. Dept. of Mechanical Engineering Massachusetts Inst. of Technology USA Huntsville. School of Graduate Studies and Research Alabama Univ. USA Dept. of Microbiology. Office of Naval Research Maryland Univ. Arlington Research and Development Co. Pittsburgh AeroChem Research Labs. Inc. Princeton Dept. of the Interior Office of Library Services. Bibliographic Series (Final) Washington D.C. Interplan Corp. Santa Barbara Urban Mass Transportation Adm. Washington D.C. Naval Underwater Systems Center Newport Calif. Mercury Project. National Science Found Stanford Univ Washington D.C. Div. of Advanced Environmental Research & Tech. USA Corvallis. NASA Earth Resources Survey Program Oregon State Univ. Washington D.C. Riverside. Inst. of Geophysics and Planetary Physics National Science Foundation California Univ. Washington D.C. Livermore Lawrence Livermore Lab. California Univ. USA Atlantic Oceanographic and Meteorological Labs. National Oceanic and Atmospheric Administration Miami National Technical Information Service Springfield Miami Univ. Coral Gables School of Law National Oceanic and Atmospheric Administration Rockville National Academy of Sciences Office of Sea Grant Washington D. C. School of Law National Oceanic and Atmospheric Administration Office of Sea Grant. Rockville Norman. Dept. of Civil Engineering and Environmental Science. Urban Mass Transportation Administration Oklahoma Univ. Washington D. C. Knoxville.Dept. of Civil Engineering. Federal Highway Administration Tennessee Univ. Washington D. C. Amherst.Water Resources Research Center. Office of Water Research and Technology Massachusetts Univ. Washington D. C. Calif. Dept. of Industria

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Combinatorial Machine Learning 1

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丛书名： Studies in Computational Intelligence

1000年

作者： Mikhail Moshkov Beata Zielosko

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