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71.
The authors have used a 3-D transmission-line matrix (TLM) modeling method to study the junction temperature distribution and power limitation of device geometries with multiple embedded heat sources. Peak values of the junction temperature against the dissipated power density under both pulsed and CW operation are presented for a typical power AlGaAs/GaAs HBT structure. These data should facilitate the rapid determination of junction temperature for a given output power, which is of paramount importance in power device design 相似文献
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The modified direct observation method is employed for the determination of the liquidus lines in the (Hg1_xZnx)1_yTey, ternary system. The liquidus temperatures of the ternary samples of various compositions withx from 0.05 to 0.30 andy from 0.5 to 0.9 are measured. The temperature-composition phase diagrams and some liquidus isotherms are established for
this system. 相似文献
75.
Efficient scheduling algorithms for the slot assignment problem in a satellite-switched time-division multiple-access (SS/TDMA) system are presented. This problem is translated into a modified open-shop scheduling problem, allowing the use of known optimal algorithms. Their complexity is expressed as a function of the following parameters: the number of nonzero entries in the demand matrix, the number of uplinks, and the number of downlinks. According to the values of these parameters, the algorithm with the lowest computational complexity can be adopted. Although the computational complexity of previously published algorithms is drastically reduced, simulation results show that the results are close to previously presented solutions in terms of the assignment duration and the number of switching matrices 相似文献
76.
Weiguo Gao Yishao Zhou 《Automatic Control, IEEE Transactions on》2003,48(11):2051-2055
A computational test for scalar positive real and strictly positive real functions is proposed in this paper. The input for this algorithm is state space representation, not necessarily minimal. It is derived for the discrete time problem, based on numerical stable eigenvalue computations. The test can be used in the continuous counterpart, which is in fact an improvement of an algorithm posed by Bai and Freund. Differences between the discrete and continuous time problems are also pointed out. 相似文献
77.
Fuzzy reasoning Petri nets 总被引:2,自引:0,他引:2
Meimei Gao MengChu Zhou Xiaoguang Huang Zhiming Wu 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2003,33(3):314-324
This paper presents a fuzzy reasoning Petri net (FRPN) model to represent a fuzzy production rule-based system. The issues of how to represent and reason about rules containing negative literals are addressed in the proposed PN model. The execution rules based on the model are defined formally using the operators in max-algebra. Then, a fuzzy reasoning algorithm is proposed to perform fuzzy reasoning automatically. The algorithm is consistent with the matrix equation expression method in the traditional PNs and allows one to exploit the maximum parallel reasoning potential embedded in the model. The legitimacy and feasibility of the proposed approach are proved and validated through a turbine fault diagnosis expert system. 相似文献
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本文简要介绍了磁光隔离器的理论、结构和分类 ,并提出了该器件今后发展的几个问题 ,最后介绍了几种磁光材料 相似文献
80.