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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Results from applying the model on a sample of contractors, the majority of whom were international and operating in Egypt, reinforces the credibility of the developed methodology, claim the authors. 相似文献
992.
Dynamic Programming (DP) applies to many signal and image processing applications including boundary following, the Viterbi algorithm, dynamic time warping, etc. This paper presents an array processor implementation of generic dynamic programming. Our architecture is a SIMD array attached to a host computer. The processing element of the architecture is based on an ASIC design opting for maximum speed-up. By adopting a torus interconnection network, a dual buffer structure, and a multilevel pipeline, the performance of the DP chip is expected to reach the order of several GOPS. The paper discusses both the dedicated hardware design and the data flow control of the DP chip and the total array.This work was supported in part by the NATO, Scientific and Environmental Affairs Division, Collaborative Research Grant SA.5-2-05(CRG.960201)424/96/JARC-501. 相似文献
993.
In a survey of the practical wind energy resource present in the Tayside Region of Scotland it was estimated that over 1500 km2 of land is suitable for wind energy development in the Region after consideration of a range of physical, technical and institutional factors. Wind speed data for this survey was obtained from the Energy Technology Support Unit (ETSU) UK Wind Speed Data Package. To verify the wind speeds obtained from the ETSU package a representative sample of sites in and around the identified areas of potential in Tayside were modelled for mean annual wind speed using the Wind Atlas Analysis and Application Program (WAsP). The wind speeds for the sites obtained from the WAsP analysis were compared with those obtained from the ETSU UK Wind Speed Data Package and conclusions drawn as to the reliability of the Tayside wind energy survey and the general applicability of the ETSU package for broad wind energy resource assessment. 相似文献
994.
995.
Scientific-Technical Center “Atomtekhénergo.” Leningrad Nuclear Power Plant. N. V. Sultanov Institute of Nuclear Reactors,
Russian Scientific Center “Kurchatovskii institut.” Translated from Atomnaya énergiya, Vol. 76, No. 6, pp. 470–473, June,
1994. 相似文献
996.
G. P. Ledneva 《Journal of Engineering Physics and Thermophysics》1994,67(3-4):960-964
Heating of spherical alumina particles by high-intensity laser radiation under vacuum conditions to the melting temperature is investigated with account for the nonuniform distribution of energy sources with respect to the particle volume.B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, Minsk. Translated fron Inzhenerno-Fizicheskii Zhurnal, Vol. 67, Nos. 3–4, pp. 307–312, September–October, 1994. 相似文献
997.
Preparation of Metal-Coated Carbon Fiber Reinforced Composites and Their Electromagnetic Properties 总被引:1,自引:0,他引:1
Medium temperature curing by infrared radiation was used to prepare electromagnetic wave absorbing multilayered plastic matrix composite materials containing metal-coated carbon fibers (MCFs). The electromagnetic properties of the materials were investigated by frequency scanning tests with microwave vector network analyzer. It is found that the electromagnetic parameters, mainly permittivity of the composites increase significantly with the addition of MCFs, which gives the composites good designability as thin, light-weight EM wave absorbers. It is also shown that MCFs can improve on the EM wave energy attenuating property of the composites by widening the work frequency band width and raising the absorptive peak 相似文献
998.
Cook R.D. Saulnier G.J. Gisser D.G. Goble J.C. Newell J.C. Isaacson D. 《IEEE transactions on bio-medical engineering》1994,41(8):713-722
Presents the design, implementation, and performance of Rensselaer's third-generation adaptive current tomograph, ACT3. This system uses 32 current sources and 32 phase-sensitive voltmeters to make a 32-electrode system that is capable of applying arbitrary spatial patterns of current. The instrumentation provides 16 b precision on both the current values and the real and reactive voltage readings and can collect the data for a single image in 133 ms. Additionally, the instrument is able to automatically calibrate its voltmeters and current sources and adjust the current source output impedance under computer control. The major system components are discussed in detail and performance results are given. Images obtained using stationary agar targets and a moving pendulum in a phantom as well as in vivo resistivity profiles showing human respiration are shown 相似文献
999.
V. V. Veremey A. A. Kostenko I. K. Kuz'michev A. E. Poyedinchuk G. I. Khlopov 《Journal of Infrared, Millimeter and Terahertz Waves》1994,15(7):1283-1295
Reported here are the results on level and structure of the radiated field of an open resonator at and off resonance. On the basis of the modelling problem rigorous solution and the measurements at 4-millimeter wavelength we find there are no ways to compensate the radiated field from an open electromagnetic structure at resonance. Analysis of open resonator excitation efficiency shows that the mismatch loss of a slot-fed open resonator runs to 34% while at the aperture-feed excitation this is not more than 6% for the same-geometry resonator. 相似文献
1000.
Howden W.E. Wieand B. 《IEEE transactions on pattern analysis and machine intelligence》1994,20(6):445-462
Formal verification of program properties may be infeasible or impractical, and informal analysis may be sufficient. Informal analysis involves the informal acceptance, by inspection, of the validity of program properties or steps in an analysis. Informal analysis may also involve abstraction. Abstraction can be used to eliminate details and concentrate on more general properties. Abstraction will result in informal analysis if it includes the use of undefined properties. A systematic, informal method for analysis called QDA (Quick Defect Analysis) is described. QDA is a comments analysis process based on facts and hypotheses. Facts are used to create an abstract program model, and hypotheses are selected, nonobvious program properties which are identified as needing verification. Hypotheses are proved from the facts that define an abstraction. QDA is hypothesis-driven in the sense that only those parts of an abstraction that are needed to prove hypotheses are created. The QDA approach was applied to a previously well tested operational flight program (OFP). The QDA method and the results of the OFP experiment are presented. The problems of incomplete or unsound informal analysis are analyzed, the relationship of QDA to other analysis methods is discussed, and suggested improvements to the QDA method are described 相似文献