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1.
对鞍钢股份无缝钢管厂连轧机前毛管坯横移装置存在的设计缺陷进行了分析,并提出改进方案,将原横移装置由高架轨道横移机构及上下升降链传动装置,改进为地面轨道横移系统及同步旋转臂实现取管、放管过程。实施后消除了生产故障,缩短了轧制周期,降低生产成本。 相似文献
2.
Due to the law of reflection, a concave reflecting surface/mirror causes the incident light rays to converge and a convex surface/mirror causes the light rays to reflect away so that they all appear to be diverging. These converging and diverging behaviors cause that the curved mirrors show different image types depending on the distance between the object and the mirror. We model such optical phenomena metaphorically into the searching process of numerical optimization by a new algorithm called optics inspired optimization (OIO). OIO treats the surface of the numerical function to be optimized as a reflecting surface in which each peak is assumed to reflect as a convex mirror and each valley to reflect as a concave one. Each individual is assumed to be an artificial object (or light point) that its artificially glittered ray is reflected back by the function surface, given that the surface is convex or concave, and the artificial image is formed (a candidate solution is generated within the search domain) based on the mirror equations adopted from physics of optics. Besides OIO, we introduce different variants of it, called ROIO (Rotation based OIO), and COIO (Convex combination based OIO) algorithms and conduct an extensive computational effort to find out the merit of the new algorithms. Our comparisons on benchmark test functions and a real world engineering design application (i.e., optimization of a centrifuge pump) demonstrate that the new algorithms are efficient and compete better than or similar to most of state of the art optimization algorithms with the advantage of accepting few input parameters. 相似文献
3.
概述了高压放大器的基本组成,以及采用高压稳压电源措施,提高高压放大器的性能,并简述了高压放大器输出级的工作原理,给出了过渡保护方法。 相似文献
4.
分片汇接的网状网结构是江苏省本地电话网的基本框架,而汇接局和连接汇接局的传输系统则是网路规划与通信建设的重点。 相似文献
5.
This paper describes an agent-based framework with a tandem integration architecture for cooperating distributed, heterogeneous, and autonomous concurrent engineering systems. The approach has been experimented with using the prototype AGENTS system. It is demonstrated that design tools can be dynamically connected and configured to construct highly complex systems on an incremental basis, designing and proving one system at a time without bothering the rest. A major advantage of the approach is the balance between the interoperability and the autonomy of individual systems. 相似文献
6.
7.
椭球反射镜膜厚均匀性 总被引:2,自引:1,他引:1
本文分析了椭球反射镜膜层厚度均匀性对反射率的影响,从理论上得到膜厚计算公式。根据计算的膜厚分布设计了遮蔽板,获得较好的反射特性。 相似文献
8.
单螺杆挤出机—熔体泵串联挤出系统的性能与应用 总被引:3,自引:0,他引:3
从原理与应用方面,分析、探讨了单螺杆挤出机-熔体泵串联挤出系统的优异性能以及在塑料挤出成型领域的高效应用。 相似文献
9.
We study tandem queues with finite intermediate buffers and develop a general blocking scheme that unifies and generalizes various blocking schemes previously studied in the literature, such as manufacturing blocking, communication blocking, kanban blocking and its variations. In the general blocking scheme, job movement and service at each stage are controlled by three parameters, which represent, respectively, the upper limits (at that stage) on work-in-process inventory, finished goods inventory, and buffer space. We derive a set of recursive equations that characterize the dynamics of the system, in terms of the job completion and departure processes, and establish comparison results for these processes in the settings of stochastic ordering, variability ordering and stochastic convexity. Free of distributional assumptions, the results provide characterization of system behavior with respect to the control parameters as well as to the arrival and service processes. We also compare system performance under two different modes of operation: make-to-order versus make-to-stock, and demonstrate the trade-off between improving service and reducing inventory. Numerical studies are also presented to illustrate the diversity of performance trade-off, including composition of inventory, offered by the general model.Supported in part by NSF under grant ECS-89-96201. 相似文献
10.
提高大口径金属主镜面形精度的方法 总被引:1,自引:1,他引:0
分析了影响Ritchey-Chreitien光学系统中金属主反射镜面形精度因素,采用有限元法对立交易的加工过程及其安装进行了模拟,指出提高主镜的面形镜度,既要合理主镜材料的热处理工艺,也要对加工参数进行控制。良好的稳定化处理可以有效地消除材料内部的残余应力,保证主镜尺寸的稳定性。提高加工基准的精度,并采用组合加工镜面,可以大大提高主镜的面形精度,最后,给出了主镜的干涉仪检测结果。 相似文献