冶钢小方坯连铸机结晶器液面控制系统故障分析及对策

本文针对某一钢铁厂的一套小方坯连铸机结晶器液面自动控制系统，对其故障原因进行了深入分析，指出导致系统控制性能达不到设计要求长期无法投入运行的主要原因，并提出了相应的解决方法。     

Linear self-stabilizing algorithms for the independent and dominating set problems using an unfair distributed scheduler

This paper presents distributed self-stabilizing algorithms for the maximal independent and the minimal dominating set problems. Using an unfair distributed scheduler the algorithms stabilizes in at most max{3n−5,2n} resp. 9n moves. All previously known algorithms required O(n²) moves.     

Longest fault-free paths in hypercubes with vertex faults

The hypercube is one of the most versatile and efficient interconnection networks (networks for short) so far discovered for parallel computation. Let f denote the number of faulty vertices in an n-cube. This study demonstrates that when f ? n − 2, the n-cube contains a fault-free path with length at least 2ⁿ − 2f − 1 (or 2ⁿ − 2f − 2) between two arbitrary vertices of odd (or even) distance. Since an n-cube is a bipartite graph with two partite sets of equal size, the path is longest in the worst-case. Furthermore, since the connectivity of an n-cube is n, the n-cube cannot tolerate n − 1 faulty vertices. Hence, our result is optimal.     

快中子零功率反应堆(DF-VI)的临界事故概率分析

本文应用故障树分析方法,对快中子零功率堆(DF-Ⅵ)在启动过程中发生临界事故的可能性做了初步的定量估计。结果表明,该堆每次启动发生临界事故的概率约为10~(-6)量级,得出确保装置启动安全的首要因素是选配合格的操作人员的结论,并对设备的改进提出了一些建议.     

应用浅层测温法寻找油气藏

地温法是非地震物化探手段中的一种常用方法，在油气普查和勘探方面已得到广泛应用，并取得了显著效果。简要介绍了地温法寻找油气藏的仪器设备、基本原理、适用范围及特点，并举例说明了其应用效果。应用高精度测温仪，通过开展浅层地温测量和研究，可以达到寻找油气的目的。     

The column protocol: A high availability and low message cost solution for managing replicated data

This paper presents a quorum-based replica control protocol which is resilient to network partitioning. In the best case, the protocol generates quorums of a constant size. When some replicas are inaccessible, the quorum size increases gradually and may be as large as O(n), where n is the number of replicas. However, the expected quorum size is shown to remain constant as n grows. This is a desirable property since the message cost for accessing replicated data is directly proportional to the quorum size. Moreover, the availability of the protocol is shown to be comparably high. With the two properties—constant expected quorum size and comparably high availability—the protocol is thus practical for managing replicated data.     

完备ARRs集的生成方法及传感器优化配置应用

广泛应用于故障诊断和传感器优化、分析、证实的解析冗余关系(Analytical redundancy relations,ARRs)缺乏系统、有效的方法来产生完备ARRs集,为此,提出了一种逐次消元法。该方法以系统元关系(Primary relations,PRs)为基础,通过若干次循环消元过程,生成了完备ARRs集,同时生成了对应的假定特征矩阵(Hypothetical signature matrix,HSM);基于HSM,把传感器优化配置问题映射为一个特殊的0-1整数规划模型,并用分支定界法求解该模型。应用表明,该方法能在不降低故障检测率、隔离率的前提下减少传感器数目,降低了测试代价,对故障诊断中的传感器配置问题有借鉴意义。     

医院局域网丢包实例解析

医院局域网的日常运维管理,经常会遇到的一种故障现象就是丢包,当网络出现传输延迟、无法连接服务器数据库等异常现象以后,如何能快速找到故障原因并排除故障．这是对网络管理人员的一大挑战,网管人员应当具备处理这种网络丢包故障的能力。列举工作中遇到的几种丢包案例,总结出故障解决的经验与心得,希望能够提高大家的分析能力和解决此类网络故障的能力。     

惯性导航装置虚拟检测仪设计

惯性导航装置是一种很重要且精密的设备,故障检测和诊断是设备维修的前提,综合采用现在的虚拟检测技术,对惯性导航装置的故障检测方法进行了研究,设计了虚拟检测仪的硬件设备,开发了虚拟检测仪的软件,完成了整个虚拟检测仪的设计。     

Soft computing approach to fault diagnosis of centrifugal pump

Fault detection and isolation in rotating machinery is very important from an industrial viewpoint as it can help in maintenance activities and significantly reduce the down-time of the machine, resulting in major cost savings. Traditional methods have been found to be not very accurate. Soft computing based methods are now being increasingly employed for the purpose. The proposed method is based on a genetic programming technique which is known as gene expression programming (GEP). GEP is somewhat a new member of the genetic programming family. The main objective of this paper is to compare the classification accuracy of the proposed evolutionary computing based method with other pattern classification approaches such as support vector machine (SVM), Wavelet-GEP, and proximal support vector machine (PSVM). For this purpose, six states viz., normal, bearing fault, impeller fault, seal fault, impeller and bearing fault together, cavitation are simulated on centrifugal pump. Decision tree algorithm is used to select the features. The results obtained using GEP is compared with the performance of Wavelet-GEP, support vector machine (SVM) and proximal support vector machine (PSVM) based classifiers. It is observed that both GEP and SVM equally outperform the other two classifiers (PSVM and Wavelet-GEP) considered in the present study.