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排序方式: 共有9116条查询结果,搜索用时 15 毫秒
991.
WLK-1微机联切装置的定值整定 总被引:1,自引:1,他引:0
WLK-1微机联切装置是福建省“保机保网”的主要措施,经研制、安装、调试单位的共同努力,现已具备投运条件。定值整定的合理性是装置投运后能否获得满意效果的重要环节。本文着重对装置的主要功能和定值整定原则作简要介绍。 相似文献
992.
钢-混凝土组合梁计算程序 总被引:1,自引:0,他引:1
针对当前钢-混凝土组合梁设计主要采用人工计算的弊端,提出CPS计算程序,在计算荷载效应时采用了有限元、离散元等力学方法和优化设计手段。实际应用证明:程序设计合理,是解决复杂多变的设计计算问题的有效方法。 相似文献
993.
A quasi-steady state model, based on two parallel modes of diffusion and a polycondensation reaction at the inside surface of a microcapsule, is formulated to compute the time of this microencapsulation process. The predicted times of encapsulation are in agreement with observed values reported in patents. It is also shown that, for small shell thickness, the process is reaction-controlled. 相似文献
994.
Andrzej onierek 《Pattern recognition letters》1983,1(5-6):299-303
In this paper pattern recognition algorithms for controlled Markov chains for different control actions are presented. It is shown how to use these algorithms in sequential diagnosis when we classify sequences of medical tests of patients under treatment. 相似文献
995.
Electric current controlled liquid phase epitaxy (LPE) of GaAs has been performed on both n+ and semi-insulating substrates. Growth is induced by current flow across the substrate-melt interface. The furnace temperature
is held constant during growth so that direct electrical control of the growth process is achieved. The dependence of the
growth rate on both the electric current density across the substrate-melt interface and the ambient furnace temperature was
determined. Current densities from 5 to 20 A/cm2 were employed and furnace temperatures ranging from 680 to 800°C were used. Sustained steady state growth rates as small
as 0.022μm/min and as large as 1.4μm/min were obtained. For a given furnace temperature and current density, the measured
growth rates on semi-insulating substrates range from 48% to 77% of the rates obtained on n+ n substrates. The surface morphology of the epitaxial layers is observed to depend on the electric current density employed
during growth. Electric current controlled doping modulation was studied in epitaxial layers grown from unintentionally doped
melts. The degree of doping modulation achieved is approximately proportional to the change in applied current density. Approximately
a 40% increase in the net electron concentration is obtained by changing the current density from 10 to 30 A/cm2 during growth. Preliminary experiments with tin doped epitaxial layers indicate that similar changes in the amount of tin
incorporation can be achieved. 相似文献
996.
997.
报废“双迫”药改制射钉弹用球扁药新工艺研究 总被引:1,自引:1,他引:0
为了解决"双迫"型废火药的处理和再利用问题,提出了一种制备射钉弹用球扁型发射药的新工艺.工艺过程包括将经过粉碎的原料药粒分散到含有分散剂的水溶液中,加入适量的乙酸乙酯溶剂使药粒表层溶胀,在搅拌剪切力和界面张力的作用下,药粒的表面发生球形化转变,再经过洗涤、分级和烘干等处理,得到表面光滑的球扁药.研究得到的适宜工艺条件为溶剂比1.0~2.0 ml·g-1,用水量为药粒的6.0倍,分散剂用量为水量的1.0%~2.0%,搅拌速率500~600 r·min-1(线速度4.0~5.0 m·s-1),溶胀温度和时间分别为65~68 ℃和30 min.成品球扁药的堆积密度由0.70 g·cm-3提高到0.95 g·cm-3以上,流出时间由7.5 s下降到4.0 s以下.在射钉枪上进行测试,其主要弹道性能达到PATMI标准的规定指标. 相似文献
998.
This paper describes a case study of a neighborhood pub in British Columbia, Canada. This case study is an examination of three common pub occupations-bartending, waitressing and cooking (n = 17). The aims of this study are to determine the biomechanical loads of job tasks identified as physically demanding for the three occupations analyzed, to assess the potential risk of musculoskeletal injury in these job tasks, and to recommend injury prevention measures. Risk of musculoskeletal injury was assessed with four validated methods (RULA, NIOSH lifting equation, Shoaf pulling model, 3D Static Strength prediction program). Tasks commonly and frequently performed were observed to pose some risk to the working populations and require investigation and changes soon as indicated by the upper extremity and low-back assessment procedures used. Mean combined compression at the lumbrosacral disc in common tasks have been demonstrated to exceed the action limit described by NIOSH. Ligament strain was observed to reach as high as 18% at the lumbosacral joint. 相似文献
999.
Gregory A. Kopp Christian Mans David Surry 《Journal of Wind Engineering & Industrial Aerodynamics》2005,93(11):843-855
The present paper, Part 2 in a four part series, focuses on the effects of solid, perimetric parapets on the wind-induced structural loads on low-rise buildings. Roof and wall pressures were measured at more than 500 locations simultaneously for five parapet heights (h=0, 0.46, 0.9, 1.8 and 2.7 m in equivalent full-scale dimensions) and three building heights (H=4.6, 9.1 and 18.3 m) with plan dimensions 31.1 by 61.6 m and a on 12 gable roof slope. The data were obtained in simulated open country and suburban terrain conditions, at a scale of 1:100, in a boundary layer wind tunnel. It was observed that the distance from the eaves edge to the reattachment point for winds normal to the wall increases from x/H∼0.4 for h/(H+h)=0 to x/H=1.8 for h/(H+h)=0.23. While mean and fluctuating point pressure distributions tend to decrease in magnitude with h, the increased areas of separated flow lead to increased loads for interior frames with the taller parapets. 相似文献
1000.