This paper presents a comparison of H/sub /spl infin////spl mu/-synthesis sliding-mode that was done for heading and depth control of the Draper Laboratory/MIT Sea Grant Sea Squirt autonomous underwater vehicle (AUV)....
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This paper presents a comparison of H/sub /spl infin////spl mu/-synthesis sliding-mode that was done for heading and depth control of the Draper Laboratory/MIT Sea Grant Sea Squirt autonomous underwater vehicle (AUV). The approximate decoupling of the AUV heading and depth dynamics allowed us to have decoupled heading and depth designs for both the H/sub /spl infin////spl mu/-synthesis and the sliding-mode methodologies. The H/sub /spl infin////spl mu/-synthesis based controllers and the sliding-mode based controllers were implemented and tested by using a simulation of the AUV full order nonlinear model (including thruster and sensor dynamics). We analyzed the performance of the controllers (for a simultaneous depth and maneuver) over the approximate range of axial velocities commanded by the AUV. The performance of the controllers in the face of additive sensor noise was also analyzed.
Raman spectroscopy and x-ray diffraction are used to characterize Gallium Nitride (GaN) films grown on (100) Gallium Arsenide (GaAs) substrates. Reflection X-ray diffraction data from (200) planes of GaAs and cubic Ga...
Raman spectroscopy and x-ray diffraction are used to characterize Gallium Nitride (GaN) films grown on (100) Gallium Arsenide (GaAs) substrates. Reflection X-ray diffraction data from (200) planes of GaAs and cubic GaN are presented. The linewidth of the cubic GaN diffraction peak is shown to be a strong function of the growth temperature. Raman spectra are presented for a series of samples grown at different temperatures. Raman scattering is characterized by strong peaks at 560 cm-1 and at 736 cm-1, corresponding to TO and LO phonon modes of cubic GaN, respectively. An additional, unexplained feature at 768 cm-1 is clearly observed in Raman spectra of c-GaN samples grown at lower temperatures. The polarization dependence of the intensity of the GaN LO phonon mode is presented and compared with the GaAs LO phonon mode to establish the relative orientation of the c-GaN epitaxy on GaAs.
Available metrics of cardiac electrograms are not considered to be adequate for activation time determination. The authors hypothesize that a deconvolution, which fits a modeled electrogram to an observed electrogram,...
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Available metrics of cardiac electrograms are not considered to be adequate for activation time determination. The authors hypothesize that a deconvolution, which fits a modeled electrogram to an observed electrogram, is possible and would provide useful metrics of observed electrograms. They developed an algorithm which fits a uniform wave with constant velocity passing under the electrode. Activation time estimates were robust for fractionated electrograms, indicating potential clinical utility.< >
作者：
IKUNO, HGONDO, MNISHIMOTO, MFaculty of Engineering
Kumamoto University Kumamoto Japan 860 Himyoshi Ikmo received his B.E.
M.E. and Ph.D. from Kyushu University in 1962 1964 and 1979 respectively. From 1967 to 1970 he was a Research Associate in Computer Science and Communication Engineering at Kyushu University. He joined the Department of Electrical Engineering and Computer Science of Kumamoto University in 1970 and is currently a Professor there. During 1983 to 1984 he was a Visiting Professor at the Polytechnic University Brooklyn NY. His research interests are in the areas of scattering diffraction and wave propagation in the theory of electromagnetics. Dr. Ikuno is a member of IEEE and IEE of Japan. Michim Gondo graduated from National Defense Academy
Yokosuka in 1985 and received his M.E. from Kumamoto University in 1990. He is currently in the doctoral program at Kumamoto University. His research interest is in three-dimensional electromagnetic scattering. Masahiko Nkhimoto received his B.S. in Electronic Engineering from Kumamoto University in 1982 and an M.S. and Ph.D. from Kyushu University in 1984 and 1987
respectively. Since 1987 he has been a Research Associate in the Department of Electrical Engineering and Computer Science Kurnamoto University. His research interests are in the areas of scattering and diffraction of electromagnetic waves.
This paper shows that the surface current density can be calculated by using approximate total tangent magnetic vector fields which are expressed by finite number of linear combination of tangent vectors of spherical ...
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This paper shows that the surface current density can be calculated by using approximate total tangent magnetic vector fields which are expressed by finite number of linear combination of tangent vectors of spherical wave functions. Sampling points are determined by considering the property of associated Legendre functions and trigonometrical functions. By setting a number of sampling points to twice the largest mode number, a computer-aided algorithm is obtained. The accuracy of the solutions is checked and the polarization dependence of the surface current densities is clarified.
作者：
BOHM, SELHAKEEM, AKHACHICHA, MDepartment of Electrical and Computer Engineering
Concordia University 1455 De Maisonneuve Blvd. West Montreal H3A 1M8 Canada Was born in Montreal
Canada on 14 September 1966. He received the B. Eng. degree in electrical engineering from Concordia University Montreal Canada in 1989. He is at present completing the M.A.Sc. degree in electrical engineering at Concordia University. (S'75–S'79–M'79–SM'86) received the Ph.D. degree from Southern Methodist University
Dallas TX in 1979. He spent the next two years working as a Visiting Professor in Egypt after which he moved to Ottawa Canada in 1982. He assumed teaching and research positions in Carleton and Manitoba Univerities and later moved to Concordia University Montreal Canada in 1983 where he is now a Professor in the Electrical and Computer Engineering Department. He has published numerous papers in IEEE and international journals in the areas of spread spectrum and networking. He is a well-known expert in these areas and serves as a consultant to many companies. His current research interests include wide-band metropolitan networks switching architectures and performance of on-board multibeam satellites acquisitionless CDMA networks code distribution and orthogonalization of CDMA signals responsive congestion control for ATM-based networks ARQ techniques and investigation of the novel SUGAR CDMA systems in fading channels. Dr. Elhakeem is a Senior Member of the Canadian Electrical Engineering Society and Armed Forces Association. He has chaired numerous technical sessions in IEEE Conferences was the Technical Program Chairman for IEEE Montech 1986 Montreal Canada. Dr. Elhakeem is the key guest editor of theIEEE Journal of Selected Areas in Communicationsfor the May June issues 1993 covering CDMA networks. Advanced Technology & Networks
VISTAR Telecommunications Inc. Ottawa Ontario K1G 3J4 Canada An Associate Director of Advanced Technology & Networks Group
VISTAR Telecommunications Inc. Ottawa Canada. He is also an Adjunct Pr
In this paper, we study the performance of a prioritized on-board baseband switch in conjunction with a multibeam satellite handling integrated services. The services considered for the analysis include voice, video, ...
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In this paper, we study the performance of a prioritized on-board baseband switch in conjunction with a multibeam satellite handling integrated services. The services considered for the analysis include voice, video, file transfer and interactive data. The prioritized switch uses both input and output buffering, switch speed-up as well as a two-phase head-of-line resolution algorithm, in order to reduce the buffer loss while maintaining acceptable user delays. The minimum required buffer capacity and switch speed-up for each service in a prioritized environment are found under uniform traffic conditions. It is shown that under uniform traffic conditions, only minimal buffering and switch speed-up are needed even for the lowest priority users. The performance dependence on the switch size is also substantially reduced with head of line resolution and buffering even in a prioritized environment.
An interlaboratory measurement round-robin was conducted by the University of Colorado and three industrial members of the Electronic Industries Association. A computational definition of mode transition matrices (MTM...
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An interlaboratory measurement round-robin was conducted by the University of Colorado and three industrial members of the Electronic Industries Association. A computational definition of mode transition matrices (MTM's) is presented, and its relationship to the basic theory of power propagation in multimode fibers is detailed. Measured data from the round-robin were used to calculate MTM's for the test components, which included four connectors, two sections of fiber cable, two power splitters, and two short fiber segments. The diagonal elements of the (2 x 2) MTM's determined from the near-field data were found to have a laboratory-to-laboratory standard deviation of approximately 10% of the average value. The off-diagonal elements were found to have a standard deviation approaching their mean value. The inherent launch dependence of MTM's is investigated as a source of the observed variation. Other sources of uncertainty such as errors in determining the core radius are also considered. Finally the implications of these results for the problem of characterizing components' intensive multimode fiber systems are discussed.
This study investigated changes in myoelectric and mechanical variables for movements made "as fast as possible" as a function of practice in the context of the dual-strategy hypothesis of motor control (Got...
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