The relative permeability of concrete using nitrogen gas

A modified version of a test, originally proposed by BRE (UK), was used to assess relative permeability to nitrogen gas of concretes cured in various ways. Three simple parameters from test plots clearly showed the effects of duration of water curing, followed by drying to constant mass at 50°C; test specimen moisture content was dominant and drying at 105°C reduced differences between concretes of very different quality. Convincing evidence was not found of differences between upper and lower ‘halves’ of cylinders nor between cast and cored ones.     

衍射法细丝直径的精密测量

分析了激光衍射法测量细丝直径技术中影响精度的几个主要因素，研究了一种微弱衍射条纹的精密处理及识别技术，有效地提高了测量精度，实测结果表明，文中讨论的技术能在１０￣５０μｍ的范围内实现正负０．１μｍ的重复精度，分辨力优于０．０１μｍ。     

Test Case Generation as an AI Planning Problem

While Artificial Intelligence techniques have been applied to a variety of software engineering applications, the area of automated software testing remains largely unexplored. Yet, test cases for certain types of systems (e.g., those with command language interfaces and transaction based systems) are similar to plans. We have exploited this similarity by constructing an automated test case generator with an AI planning system at its core. We compared the functionality and output of two systems, one based on Software Engineering techniques and the other on planning, for a real application: the StorageTek robot tape library command language. From this, we showed that AI planning is a viable technique for test case generation and that the two approaches are complementary in their capabilities.     

埋地管道涂层检测技术现状

文章对各种埋地管道涂层检测技术进行了综述,并指出了各种技术的优缺点及应用前景.     

超声波车辆车轴探头的研制与应用

提出了一种用于检测在役车辆车轴产生疲劳裂纹的超声波方法,设计了中心孔探头与斜角探头一起,完成了对车辆车轴的关键区域探伤。     

采用区内C／I平衡的多区峰窝CDMA系统下行链路的性能

本文对采用区内Ｃ／Ｉ平衡的多区蜂窝ＣＤＭＡ系统下行链路的性能进行分析，给出两种区内Ｃ／Ｉ平衡算法并比较它们的性能，考虑呈对数正态分布的阴影和Ｒ＾－４规律的路径损失的综合影响，采用与传统不同的小区平均中断概率来评价系统的性能。     

地地战术导弹飞行可靠性指标评定方法

在小子样情况下 ,利用系统和分系统试验数据对导弹的飞行可靠性指标进行评定 ,从数学上说是系统可靠性综合问题 .运用MML SR方法对新型号地地战术导弹的飞行可靠性指标进行评定 ,避免了MML方法在遇到无失败单元时不适用的缺陷 ,在利用地面试验信息方面有其明显优势 ;运用Bayes方法对改进型导弹的飞行可靠性指标进行评定 ,将不同试验阶段的多源试验信息作为验前信息 ,扩大了信息量 .最后 ,对两种方法在工程应用上遇到的问题进行了讨论 ,并给出了解决方法 .     

A Built-in Self-Test Scheme with Diagnostics Support for Embedded SRAM

In this paper we propose a novel built-in self-test (BIST) design for embedded SRAM cores. Our contribution includes a compact and efficient BIST circuit with diagnosis support and an automatic diagnostic system. The diagnosis module of our BIST circuit can capture the error syndromes as well as fault locations for the purposes of repair and fault/failure analysis. In addition, our design provides programmability for custom March algorithms with lower hardware cost. The combination of the on-line programming mode and diagnostic system dramatically reduces the effort in design debugging and yield enhancement. We have designed and implemented test chips with our BIST design. Experimental results show that the area overhead of the proposed BIST design is only 2.4% for a 128 KB SRAM, and 0.65% for a 2 MB one.     

可靠性试验样本量和截尾时间的计算

可靠性寿命试验中，一般都因受到费用和时间的限制，因此要用截尾试验获得信息，再据此对其可靠性进行统计推断，用非参数估计的方法探讨了进行可靠性试验的样本量或截尾时间的估计方法。     

步进式加热炉钢坯跑偏测试

钢坯在炉内的横向跑偏和纵向跑偏位移量,是步进式加热炉设备的重要性能之一.重点介绍了鞍钢1780热连轧生产线步进式加热炉钢坯跑偏测试的应用技术.