对混凝土中活性掺合料几个问题的讨论

伴随混凝土活性掺合料的广泛应用,出现了一系列的问题值得注意与研究,如硅灰混凝土的塑性开裂与早期收缩;高掺粉煤灰的早期活性激发;活性掺合料的最大掺量问题等。笔者对此进行了粗陋分析,以期起到抛砖引玉之效。     

基于局域网多播技术的有效集中控制

文中介绍了多播技术及多播软件的具体实现,该控制软件系统采用VC＋＋6．0并结合Windows多线程技术开发,主要用于一台主机对对等局域网的其他站点主机进行有效控制。最后,针对多播方式采用无连接、无确认的UDP协议在数据实时性和可靠性传输中容易产生数据丢失的缺陷,从精简控制指令、定时重发与定时回馈、多线程技术等三个方面解决了以上的一些缺陷,从而提高了整个系统的可靠性、稳定性、及时性。     

Sequential fault diagnosis strategy with imperfect tests considering life cycle cost

The problem of sequential fault diagnosis is to construct a diagnosis tree that can isolate the failure sources with minimal test cost. Pervious sequential fault diagnosis strategy generating algorithms only consider the execution cost at application stage, which may result in a solution with poor quality from the view of life cycle cost. Furthermore, due to the fact that uncertain information exists extensively in the real-world systems, the tests are always imperfect. In order to reduce the cost of fault diagnosis in the realistic systems, the sequential fault diagnosis problem with imperfect tests considering life cycle cost is presented and formulated in this work, which is an intractable NP-hard AND/OR decision tree construction problem. An algorithm based on AND/OR graph search is proposed to solve this problem. Heuristic search based on information theory is applied to generate the sub-tree in the algorithm. Some practical issues such as the method to improve the computational efficiency and the diagnosis strategy with multi-outcome tests are discussed. The algorithm is tested and compared with previous algorithms on the simulated systems with different scales and uncertainty. Application on a wheel momentum system of a spacecraft is studied in detail. Both the simulation and application results suggest that the cost of the diagnosis strategy can be reduced significantly by using the proposed algorithm, especially when the placement cost of the tests constitutes a large part of the total cost.     

无外圈圆柱滚子轴承外复圆直径的测量

通常无外圈圆柱滚子轴承外复圆直径尺寸通过标准外圈测量游隙的方法计算得出,在此介绍了采用比较测量法直接测量无外圈圆柱滚子轴承外复圆直径尺寸的测量原理。     

圆锥滚子轴承和圆柱滚子轴承油沟宽度样板的改进

分析圆锥滚子轴承和圆柱滚子轴承油沟宽度检测用样板的设计特点和测量方法,从样板的通用性考虑,对油沟宽度样板进行了改进。     

聚葡萄糖在酸奶中的应用优势及高纤酸奶市场趋势

聚葡萄糖是一种优良的水溶性膳食纤维,具有良好的理化特性和健康功效。重点阐释了聚葡萄糖在酸奶中的应用优势与酸奶市场现状,并分析了未来酸奶市场的发展趋势及高纤酸奶的巨大市场潜力。     

浅谈气体公司绿色照明系统改造

介绍和总结气体公司实施绿色照明系统技术改造前后的变化,指出实施绿色照明的方法和意义。     

直接进样—气相色谱法分析低碳脂肪酸

一、前言衍生气相色谱法分析脂肪酸一般是将脂肪酸转化成不同的衍生物——脂肪酸的甲酯、乙酯、丁酯、苄酯,然后再进行色谱测定。这些方法处理样品程序复杂、费     

S波段极低噪声超导滤波放大组件

介绍了S波段极低噪声超导滤波放大组件的设计过程,采用了低温仿真建模和拓扑结构优化设计关键技术.该组件将用于接收系统中的的低温接收前端,能提高雷达的灵敏度和有效作用距离.该组件由超导滤波器和低温放大器组成,具有体积小、重量轻、可靠性高等特点.     

关于中国烟草卷烟品牌培育的思考

分析了目前我国烟草品种培育存在的问题,认为缺乏完善的培育体系、工商业双方利益不对称及品牌所有权归属不清是影响品牌培育的主要原因,并提出培育卷烟品牌必须明确各方职责、规范品牌定位、搭建培育平台。