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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
This paper introduces the research progress of the State Key Laboratory of Information Security (SKLOIS) in China during 2002–2006.
This introduction covers four selected areas with each covering some selected research findings. The four selected areas are:
the fundamentals of cryptography; the design, analysis and testing of block cipher algorithms; the design and analysis of
security protocols based on computational intractability; authentication, authorization and their applications. 相似文献
932.
Vincenzo Augelli Teresa Ligonzo Roberto Murri Luigi Schiavulli 《Thin solid films》1989,170(2):163-170
Hydrogenated and chlorinated silicon films were used to deposit Schottky barrier solar cells. Photovoltaic characterization, together with the results of electronic transport measurements, led to the conclusion that the presence of chlorine is detrimental to the properties of this kind of device. 相似文献
933.
Sidhartha R. Das Basheer M. Khumawala 《International Journal of Flexible Manufacturing Systems》1991,3(2):121-147
Flexible manufacturing systems (FMSs) are a class of automated systems that can be used to improve productivity in batch manufacturing. Four stages of decision making have been defined for an FMS—the design, planning, scheduling, and control stages. This research focuses on the planning stage, and specifically in the area of scheduling batches of parts through the system.The literature to date on the FMS planning stage has mostly focused on the machine grouping, tool loading, and parttype selection problems. Our research carries the literature a step further by addressing the problem of scheduling batches of parts. Due to the use of serial-access material-handling systems in many FMSs, the batch-scheduling problem is modeled for a flexible flow system (FFS). This model explicitly accounts for setup times between batches that are dependent on their processing sequence.A heuristic procedure is developed for this batch-scheduling problem—the Maximum Savings (MS) heuristic. The MS heuristic is based upon the savings in time associated with a particular sequence and selecting the one with the maximum savings. It uses a two-phase method, with the savings being calculated in phase I, while a branch-and-bound procedure is employed to seek the best heuristic solution in phase II. Extensive computational results are provided for a wide variety of problems. The results show that the MS heuristic provides good-quality solutions. 相似文献
934.
Zinc-containing nanoparticles stable in the liquid phase are synthesized by the radiation chemical reduction of zinc ions
in solutions of inverse micelles. The effects of the absorbed radiation dose and the size of the micelle water pool on the
spectral characteristics of samples are studied. The HPLC and electron microscopy results indicate that the composition of
nanoparticles synthesized depends on the salt nature.
Original Russian Text ? A.A. Revina, E.V. Oksentyuk, A.A. Fenin, 2007, published in Zashchita Metallov, 2007, Vol. 43, No.
6, pp. 613–618. 相似文献
935.
BT项目实施模式分析 总被引:1,自引:0,他引:1
根据实践中出现的各种BT项目管理模式,归纳出了具有代表性的“施工二次招标型BT模式,直接施工型BT模式,施工同体型BT模式,带资承包型BT模式”四种BT项目管理模式,并根据现行法律法规对其适用性和实施中应注意的问题进行了论述。 相似文献
936.
Li Yonghua Wang Chunbo Chen Hongwei 《Frontiers of Energy and Power Engineering in China》2007,1(1):96-100
Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons. So it is of great necessity
to investigate the combustion of blended coals. Using a test rig with a capacity of 640 MJ/h with an absolute milling system
and flue gas online analysis system, characteristics such as burnout, slag, and pollution of some blended coals were investigated.
The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced. The results show that
the blending of coal has some effect on NO
x
but there is no obvious rule. SO
x
emission can be reduced by blending low sulfur coal.
Translated from Proceedings of the CSEE, 2005, 25(18): 97–103 [译自: 中国电机工程学报] 相似文献
937.
938.
周同根 《中国制造业信息化》2005,34(7):110-111
利用主控零件并引入过渡装配体,将主控零件合并至产品各零件,实现用主控零件控制产品设计变更,发挥参数化设计的强大功能。 相似文献
939.
940.
A. Koblischka-Veneva M. R. Koblischka K. Ogasawara F. Mücklich M. Murakami 《Journal of Superconductivity》2005,18(4):469-474
Local orientations of superconducting YBa2Cu3O
x
(123) and embedded Y2BaCuO5 (211) particles within bulk, melt-textured 123 samples are studied on a local scale by means of electron backscatter diffraction
(EBSD). The embedded Y2BaCuO5 (211) particles do not show any preferred texture, but their presence within the 123-matrix alters the growth of the 123-phase,
independent of the orientation. EBSD enables to analyse the interactions between the 123- and 211-phases in detail. 相似文献