Reward optimization of a repairable system

This paper analyzes a system subject to repairable and non-repairable failures. Non-repairable failures lead to replacement of the system. Repairable failures, first lead to repair but they lead to replacement after a fixed number of repairs. Operating and repair times follow phase type distributions (PH-distributions) and the pattern of the operating times is modelled by a geometric process. In this context, the problem is to find the optimal number of repairs, which maximizes the long-run average reward per unit time. To this end, the optimal number is determined and it is obtained by efficient numerical procedures.     

QD-Janus: A sequential implementation of Janus in Prolog

Janus is a language designed for distributed constraint programming. This paper describes QD-Janus, a sequential implementation of Janus in Prolog. The compiler uses a number of novel analyses and optimizations to improve the performance of the system. The choice of Prolog as the target language for a compiler, although unusual, is motivated by the following: (i) the semantic gap between Janus and Prolog is much smaller than that between Janus and, say, C or machine language—this simplifies the compilation process significantly, and makes it possible to develop a system with reasonable performance fairly quickly; (ii) recent progress in Prolog implementation techniques, and the development of Prolog systems whose speeds are comparable to those of imperative languages, indicates that the translation to Prolog need not entail a significant performance loss compared to native code compilers; and (iii) compilation to Prolog can benefit immediately from a significant body of work on, and implementations of, parallel Prolog systems. Our experience indicates that translation of logic programming languages to Prolog, accompanied by the development of good program analysis and optimization tools, is an effective way to quickly develop flexible and portable implementations with good performance and low cost.     

Linear periodically time-varying discrete-time systems: Aliasing and LTI approximations

Linear periodically time-varying (LPTV) systems are abundant in control and signal processing; examples include multirate sampled-data control systems and multirate filter-bank systems. In this paper, several ways are proposed to quantify aliasing effect in discrete-time LPTV systems; these are associated with optimal time-invariant approximations of LPTV systems using operator norms.     

WZ—C系列密封阀结构分析与改进

对W Z-C系列无料钟高炉炉顶布料设备上、下密封阀在涟钢3#高炉的使用情况进行了论述,分析了故障产生的机理,对密封阀的结构进行了改造并取得了相当可观的经济效益。     

便携式多功能找星仪

找星仪是卫星地面站安装、调试、维修所必不可少的设备。旧的找星仪笨重、由于必须两人操作,很不方便。针对这些问题开发了便携式多功能找星仪。本文主要介绍了该设备的构成及其电路原理。     

精铸件结构优化设计实践

以6种典型的精密铸件为例，利用“6个千方百计”原则对产品结构进行优化设计，同时辅助有限元分析对优化结果进行再验证。通过减少大平面、避免深长孔、采用加强筋等优化措施，有效地避免了夹砂、鼓包、跑火、缩孔、裂纹等铸造缺陷，实现了少无切削和减轻铸件质量。     

热轧厂35kV右母线滤波装置优化

热轧厂在轧制难度大的产品时，引进的３５ｋＶ右母线滤波装置经常过流跳闸，并影响主变压器跳闸。通过现场测试，对过流跳闸原因进行综合分析，确定了设备优化改造对策。经１年多时间的实践考核证明改造是成功的。     

气凝胶──一种结构可控的新型功能材料

气凝胶是一种结构可控的新型轻质纳米多孔性非晶固态材料，具有许多特殊性质，因而蕴藏着广阔的应用前景。本文综述了气凝胶材料的制备方法、结构控制原理、性质和各种可能的应用。     

多站远程无线控制信号系统通信软件的开发

多站远程无线控制系统是以计算机为中心控制 ,用多个信号源作为下位机通过无线模块进行通信 ,文中介绍了通过无线数传模块实现无线通讯以及ActiveX控件的使用方法 ,提出了使系统应用程序更安全可靠 ,效率更高 ,维护更加方便的几种措施。     

Novel Fiberoptic Sensing Array an Fundamental Experiments

A suitable fiberoptic sensing array embedded in the smart structure to monitor quasi-distrbuted froces on the structrue in presented in this paper.Artificial neural networks are used in processing of fiberoptic sensing array signals.Fundamental experiments have been done and the results are also given.