与性能相关的容错计算系统可靠性指标

对于某些容错计算系统，由于成功与故障之间没有明确的界限，用传统的可靠性指标难以准确地评价其容错性能，为此一些学者提出了若干与性能相关的可靠性指标。本文将这些指标概括成三类（即基于瞬时性能的指标、基于累积收益的指标和率模可靠性指标）加以介绍，并简要介绍了它们的求解方法。     

On GID-Testable Two-Dimensional Iterative Arrays

A new approach is presented for easily testable two-dimensional iterative arrays.It is an improvement of GI-testability (Group Identical testability)and is referred to as GID-testability (Group Identical and Different testability).In a GID-testable two-dimensional array,the primary x and y outputs are organized into groups and every group has more than one output.This is similar to the GI-testable arrays.However,GID-testability not only ensures that identical test responses can be obtained from every output in the same group when an array is fault free,but also ensures that at least one output has different test responses (from the other outputs in a group)when a cell in the array is faulty.Therefore,all faults can be detected under the assumption of a single faulty cell model.It is proved that an arbitrary two-dimensional iterative array is GID-testable if seven x-states and seven y-states are added to the original flow table of the basic cell of the array.GID-testability simplifies the response verification of built-in-self-testing in a way similar to PI-and GI-testability^[6-9].Therefore,it is suitable for BIST design.     

Structural study of degraded ZnMgSSe blue light emitters

Using electroluminescence (EL) topography and transmission electron microscopy (TEM), we investigated the nonluminescent regions which form while current is being injected into ZnMgSSe/ZnSSe/ZnCdSe-based blue light emitters. Small dark spots were observed just after turn-on and spread out forming rough nonluminescent triangles in the <100> directions in the EL image of the active region. TEM studies showed that the small dark spots are pre-existing stacking faults originating at the substrate/epitaxial layer interface. The nonluminescent triangles were found to be a dense region of dislocation dipoles and dislocation loops. Each dipole was aligned along two <110> directions in the {111} planes. The Burgers vectors were of the type a/2<011> inclined at 45° to the (001) junction plane.     

Analyzing the Reliability of Degradable Networks

The reachability of a strongly connected network may be destroyed after link damage,Since many networds have directed links with the potential for reversal,the reachability may be restored by reversing the direction of links.In this paper,the reliability of a network that allows reversal of links in discussed.     

一种适合于同杆4回线的故障测距方法

在对同杆4回线解耦的基础上，提出了一种适合于同杆4回线的故障测距方法。同杆4回线内部发生故障时，可以将故障分量分解为12序分量，且利用该12序分量进行故障测距。考虑到在任何故障类型下，同杆4回线内部都会存在反序分量，所以提出了基于反序环流分量的故障测距方法。当同杆4回线内部发生故障时，从线路两端计算到故障点的反序环流分量电压相等，利用该关系可以求出故障点的精确位置。由于相互独立的12序分量完全能够解决线间耦合问题，文中提出的测距算法能够精确测距，测距精度不受故障类型影响。大量ATP仿真结果表明所提出的测距算法完全适用于同杆4回线的故障测距，测距精度不受过渡电阻、系统运行方式、线路两端功角的影响。     

VXIbus模块仪器在电路印制板故障诊断系统中的应用

本文介绍了一个由VXIbus模块仪器组建的用于电路印制板故障诊断的自动测试系统,具体的讨论了组建中的主控计算机和接口控制器的选择及被测单元与自动测试设备之间通用接口设计等问题。在文章的最后,给出了测试软件设计实例。实际应用表明,VXIbus模块仪器的应用,为电路印制板故障诊断系统提供了优良的测试性能,使系统的实用行、通用性、灵活性及自动化程度得到了明显的提高。     

用瞬态频率波动法诊断齿轮故障

利用瞬态频率波动法实现频率调制信号的解调，提取齿轮的局部裂纹信息，并通过黄河ＴＮ２５２型汽车变速器疲劳试验的信号分析来验证。     

电荷灵敏放大器不用反馈高值电阻的新方法

本文提出了一种电荷灵敏放大器不用反馈高值电阻的新方法。对这种方法作了电路分析以及对实际电路的测量结果作了介绍。     

全断面双护盾掘进机在引黄工程断层破碎带的卡机处理

万家寨引黄工程国际Ⅱ、Ⅲ标已查明的断层有34条，隐伏断层可能还有一些，除了利民堡区域性大断层（F32）外，较大的集中于7#洞北段59＋700—68＋820，主要有F65、F70、F90、F74。全断面双护盾掘进机适应于较复杂的地质条件，因此在通过断层破碎带时一般都较正常。但在通过引黄工程区域性大断层F65时，发生了卡机事故，处理用了3个月时间。该文对处理TBM卡机事故的施工进行了总结。     

电动钻机的工作理论基础(一)--系列专题之七

近年来，电驱动已成为石油钻机的主要驱动形式，是钻机自动化、智能化的坚实平台。文章就电动钻机的部分工作理论作初步剖析，包括钻机工作机组对电驱动的要求，可控硅直流电驱动和交流变频电驱动的工作原理，直流电动机和交流变频电动机等的特性分析，电动机的四象限运行和能耗制动原理等。