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介绍了一个应用力传感器组成的智能机器人精密装配作业的宏/微操作系统,它能够完成一般凸形销孔零件沿任意方向的精密装配作业。 相似文献
69.
Kensuke Konishi Jun-Ichi Toyooka Kenji Kamiyama Ikken Sato Shigenobu Kubo Shoji Kotake Kazuya Koyama Alexander D. Vurim Valery A. Gaidaichuk Alexander V. Pakhnits Yuri S. Vassiliev 《Nuclear Engineering and Design》2007,237(22):2165-2174
The WF (wall failure) test of the EAGLE program, in which 2 kg of uranium dioxide fuel-pins were melted by nuclear heating, was successfully conducted in the IGR (Impulse Graphite Reactor) of NNC/Kazakhstan. In this test, a 3 mm-thick stainless steel (SS) wall structure was placed between fuel pins and a 10 mm-thick sodium-filled channel (sodium gap). During the transient, fuel pins were heated, which led to the formation of a fuel-steel mixture pool. Under the transient nuclear heating condition, the SS wall was strongly heated by the molten pool, leading to wall failure. The time needed for fuel penetration into the sodium-filled gap was very short (less than 1 s after the pool formation). The result suggests that molten core materials formed in hypothetical LMFBR core disruptive accidents have a certain potential to destroy SS-wall boundaries early in the accident phase, thereby providing fuel escape paths from the core region. The early establishment of such fuel escape paths is regarded as a favorable characteristic in eliminating the possibility of severe re-criticality events. A preliminary interpretation on the WF test results is presented in this paper. 相似文献
70.
Response time variability is a new optimization problem with a broad range of applications and a distinctive number of theoretic
flavour. The problem occurs whenever events, jobs, clients or products need to be sequenced so as to minimize the variability
of time for which they wait for the next turn in obtaining the resources necessary for their advance. The problem has numerous
real-life applications. We study its computational complexity, present efficiency, polynomial time algorithms for some cases,
and the NP-hardness proof for a general problem. We propose a position exchange heuristic and apply it to improve the total
response time variability of an initial sequence. The latter is the optimum bottleneck sequence, Webster or Jefferson sequence
of the apportionment, or a random sequence. We report on computational experiments with the heuristic. 相似文献