Reliability Analysis on the δ-Shock Model of Complex Systems

We investigate the delta-shock model of complex systems consisting of n i.i.d. components. We first obtain a general lifetime distribution for the delta-shock model of a general complex system by reducing the system to a linear combination of parallel systems. We then consider coherent system structures including series, parallel, and k-out-of-n, then derive some useful results including reliability bounds, bounds on the mean lifetime, limiting distributions, and Laplace-Stieltes transforms     

中压变频器在宣钢炼钢厂除尘风机中的应用

本文介绍了SIMOVERT MV中压变频器在宣钢炼钢厂一次除尘风机中的应用情况。变频器现场运行表明，采用中压变频器对转炉除尘风机进行调速节能获得了成功，节能效果明显。     

房屋建筑结构无损检测方法的分析与展望

通过对现有的结构无损检测方法的总结和分析,讨论了各种方法的优缺点.并结合现场测试的要求,展望结构检测技术的发展方向与趋势.     

CSP工艺生产微钛钢中的碳氮化物析出相

在钢中添加一定量的Ti可以提高钢的力学性能。细小的TiN弥散粒子可起到一些有利作用。例如，TiN粒子可以细化钢的铸态组织；减少有害夹杂物的析出；提高奥氏体粗化温度；防止形成过大的奥氏体晶粒等。     

企业经营理念的思考

在经营实践中,企业的灵魂是经营理念,成功的企业必有科学、合理的经营理念做指导,经营理念是企业生存发展的决定因素.     

Impact of temperature cycle profile on fatigue life of solder joints

In this paper the influence of the temperature cycle time history profile on the fatigue life of ball grid array (BGA) solder joints is studied. Temperature time history in a Pentium processor laptop computer was measured for a three-month period by means of thermocouples placed inside the computer. In addition, Pentium BGA packages were subjected to industry standard temperature cycles and also to in-situ measured temperature cycle profiles. Inelastic strain accumulation in each solder joint during thermal cycling was measured by high sensitivity Moire interferometry technique. Results indicate that fatigue life of the solder joint is not independent of the temperature cycle profile used. Industry standard temperature cycle profile leads to conservative fatigue life observations by underestimating the actual number of cycles to failure.     

热重分析对高分子材料中碳酸钙的定量研究

碳酸钙是高分子材料中常用的无机填料，在高温时会同二氧化碳而失重。利用热重分析可准确定出高分子材料中碳酸钙的含量，同时还可测出聚合物，挥发物的含量，热重分析法样品用量小，灵敏度高，所需时间短。     

电冰箱压缩机过载保护器匹配试验研究

过载保护器是避免压缩机电机烧毁的一个关键部件。本文阐述了过载保护器的匹配试验方法 ,并成功运用于 CFCs替代工质新产品的开发之中。