Results 191 to 200 of about 14,076 (241)
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Journal of the Structural Division, 1969
Simply supported multibeam bridges with elements of solid or box section are considered. The structure is idealized as a series of discrete beams, which may include edge beams, joined by longitudinal hinges. The structure is analyzed by a computer-oriented direct flexibility technique, using harmonic analysis to reduce the two-dimensional problem to a ...
Graham H. Powell +2 more
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Simply supported multibeam bridges with elements of solid or box section are considered. The structure is idealized as a series of discrete beams, which may include edge beams, joined by longitudinal hinges. The structure is analyzed by a computer-oriented direct flexibility technique, using harmonic analysis to reduce the two-dimensional problem to a ...
Graham H. Powell +2 more
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1969 International Electron Devices Meeting, 1969
CRT devices, both for photorecording and real time display applications, can be improved in certain of their characteristics by utilizing a number of electron beams simultaneously modulated in the tube. A plurality of beams, when properly generated, focused and deflected, will display information with writing speed, video band-width and brightness ...
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CRT devices, both for photorecording and real time display applications, can be improved in certain of their characteristics by utilizing a number of electron beams simultaneously modulated in the tube. A plurality of beams, when properly generated, focused and deflected, will display information with writing speed, video band-width and brightness ...
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2017
Multibeam echosounders have revolutionized our ability to resolve seabed geomorphology and regionally define its substrate. Using a fan of narrow acoustic beams, the slant ranges, angles and returned backscattered intensity can be employed to define the seabed elevation and infer the substrate.
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Multibeam echosounders have revolutionized our ability to resolve seabed geomorphology and regionally define its substrate. Using a fan of narrow acoustic beams, the slant ranges, angles and returned backscattered intensity can be employed to define the seabed elevation and infer the substrate.
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A Multibeam Cassegrain Antenna
1975 5th European Microwave Conference, 1975This paper deals with generation of a multibeam pattern for three-dimensional radar surveillance by a stacked feed horn system installed in a Cassegrain antenna. Although its effective f/D-ratio is relatively high compared with the corresponding one of the primarily feed paraboloid, lateral displacement of feed horns in the focal plane results in ...
H. Gniss, E. Zocher
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Multiuser decoding for multibeam systems
IEEE Transactions on Vehicular Technology, 2000An iterative multiuser decoding algorithm for co-channel BPSK/QPSK users in a multibeam system is presented. The approach can be applied to the return link of multibeam satellites and to terrestrial systems with sectored base-station antennas. It allows the reuse of the same spectrum in each beam.
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Multibeam and Multibarrel Gyrotrons
2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2019The report analyzes the perspective of multibeam and multibarrel version of gyrotron for possibility of frequency tuning and improved mode selection at gyrotron working on the gyrofrequency harmonics.
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1992
We present here the development of a multibeam echosounder. Its specifications have been defined for fishing applications. The L.M.P. has managed the preliminary studies and the realization of the prototype with the support of IFREMER (Institut Francais pour la Recherche et l’Exploitation de la MER) which has also organized the sea trials on an ...
P. Challande +4 more
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We present here the development of a multibeam echosounder. Its specifications have been defined for fishing applications. The L.M.P. has managed the preliminary studies and the realization of the prototype with the support of IFREMER (Institut Francais pour la Recherche et l’Exploitation de la MER) which has also organized the sea trials on an ...
P. Challande +4 more
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IEEE Transactions on Microwave Theory and Techniques, 1992
The Advanced Communication Technology Satellite (ACTS), to be launched in 1993, is introduced briefly, and then the Ka-band multibeam antenna, consisting of electrically similar 30 GHz receive and 20 GHz transmit offset Cassegrain systems utilizing orthogonal linear polarizations, is described.
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The Advanced Communication Technology Satellite (ACTS), to be launched in 1993, is introduced briefly, and then the Ka-band multibeam antenna, consisting of electrically similar 30 GHz receive and 20 GHz transmit offset Cassegrain systems utilizing orthogonal linear polarizations, is described.
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Proceedings of the IEEE, 1968
The application of general N-port Butler matrices to the generation of multiple beams-from planar arrays is described. It is shown that the array must satisfy a "covering" condition. The interconnection of array and matrix is derived. The method, for determination of beam position is developed and applied to rectangular arrays to improve beam crossover
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The application of general N-port Butler matrices to the generation of multiple beams-from planar arrays is described. It is shown that the array must satisfy a "covering" condition. The interconnection of array and matrix is derived. The method, for determination of beam position is developed and applied to rectangular arrays to improve beam crossover
openaire +1 more source