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排序方式: 共有357条查询结果,搜索用时 328 毫秒
141.
The use of detecting arrays (DTAs) is motivated by the need to locate and detect interaction faults arising between the factors in a component-based system in software testing. The optimality and construction of DTAs have been investigated in depth for the case in which all the interaction faults are assumed to have the same strength; however, as a practical concern, the strengths of these faults are not always identical. For real world applications, it would be desirable for a DTA to be able to identify and detect faulty interactions of a strength equal to or less than a specified value under the assumption that the faulty interactions are independent from one another. To the best of our knowledge, the optimality and construction of DTAs for independent interaction faults have not been studied systematically before. In this paper, we establish a general lower bound on the size of DTAs for independent interaction faults and explore the combinatorial feature that enable these DTAs to meet the lower bound. Taking advantage of this combinatorial characterization, several classes of optimum DTAs meeting the lower bound are presented. 相似文献
142.
Robust PCA-Based Abnormal Traffic Flow Pattern Isolation and Loop Detector Fault Detection 总被引:1,自引:0,他引:1
One key function of intelligent transportation systems is to automatically detect abnormal traffic phenomena and to help further investigations of the cause of the abnormality. This paper describes a robust principal components analysis (RPCA)-based abnormal traffic flow pattern isolation and loop detector fault detection method. The results show that RPCA is a useful tool to distinguish regular traffic flow from abnormal traffic flow patterns caused by accidents and loop detector faults. This approach gives an effective traffic flow data pre-processing method to reduce the human effort in finding potential loop detector faults. The method can also be used to further investigate the causes of the abnormality. 相似文献
143.
Emmanuel Agullo Luc Giraud Abdou Guermouche Jean Roman Mawussi Zounon 《Numerical Linear Algebra with Applications》2016,23(5):888-905
As the computational power of high‐performance computing systems continues to increase by using a huge number of cores or specialized processing units, high‐performance computing applications are increasingly prone to faults. In this paper, we present a new class of numerical fault tolerance algorithms to cope with node crashes in parallel distributed environments. This new resilient scheme is designed at application level and does not require extra resources, that is, computational unit or computing time, when no fault occurs. In the framework of iterative methods for the solution of sparse linear systems, we present numerical algorithms to extract relevant information from available data after a fault, assuming a separate mechanism ensures the fault detection. After data extraction, a well‐chosen part of missing data is regenerated through interpolation strategies to constitute meaningful inputs to restart the iterative scheme. We have developed these methods, referred to as interpolation–restart techniques, for Krylov subspace linear solvers. After a fault, lost entries of the current iterate computed by the solver are interpolated to define a new initial guess to restart the Krylov method. A well‐suited initial guess is computed by using the entries of the faulty iterate available on surviving nodes. We present two interpolation policies that preserve key numerical properties of well‐known linear solvers, namely, the monotonic decrease of the A‐norm of the error of the conjugate gradient or the residual norm decrease of generalized minimal residual algorithm for solving. The qualitative numerical behavior of the resulting scheme has been validated with sequential simulations, when the number of faults and the amount of data losses are varied. Finally, the computational costs associated with the recovery mechanism have been evaluated through parallel experiments. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
144.
自然界绝大多数断裂,尤其是控矿断裂均具明显的多期活动特征。擦痕是从事断裂多期活动特征研究中较直观、实用的标志之一。文章对断裂带内擦痕发育的复杂性、多变性特征与原因,以及多期活动控矿断裂的擦痕发育特征判析等问题,进行了初步分析与探讨。 相似文献
145.
对Ps-6型光谱仪作了简介的基础上,从联锁保护电路入手,选择了射频发生器。相检测电路,气路,真空系统,光路准直监视系统,光电倍增管和高压电路等八例有代表性,。已排除的故障实例深入进行了研究,提出了排除故障的思路与办法。 相似文献
146.
147.
浅析几种典型网络故障排查方法 总被引:1,自引:1,他引:0
在实际网络设备管理工作中,遇到网络故障时,要采用“观察现象-分析原因-排查纠错-测试运行-恢复运行”的方法对故障进行处理;并且,对于不同的故障要有不同的处理预案,以提高网络设备管理效能。 相似文献
148.
济阳坳陷中、新生代断裂活动强度研究 总被引:22,自引:0,他引:22
济阳坳陷是非烃气藏的富集区。这些气藏与火山活动有密切的成生关系,同时火山活动与断裂活动也有密切的关系。济阳坳陷内断裂活动极为发育,通过断层生长指数等的分析,推断中生代断裂以北西向为主,新生代则兼有北西向、北东向和近东西向的断裂,上述断裂发育特征反映了该区的大地构造背景,在中生代是左旋的剪切应力场,在新生代则是右旋的剪切应力场。 相似文献
149.
Benfu Hu Quanmao Yu Lin Lu Chengchang Jia Hiroshi Kinoshita Heishichiro Takahashi 《矿物冶金与材料学报》2002,9(4):292-297
Fe-Cr-Mn(W, V) austenite steels used as low radioactive structural materials in fusion reactor have been investigated. The resultsshow that the high temperature strength and the creep fracture life of Fe-Cr-Mn(W, V) steels can be effectively improved through (C+N) complex-strengthening, so can be the high temperature ductility. The strength and ductility of the steels are superior to that of SUS316 steels and JPCAS below 673K. The relationship between strength, ductility andthe formation temperature is related to the evolution of deformation microstructure. The fracture and microstructure observation above 673Kindicates that the main way to further improve ductility at high temperature is the control of carbide coarsening at the grain boundaries. 相似文献
150.
分析了不同空间位置盆地的构造演化差异性,并结合区域构造事件探讨了中非裂谷盆地的构造动力学成因机制。中非裂谷盆地包括两个分支体系:西非裂谷系主要呈左旋走滑双断式结构;中非裂谷系主要表现为单断式右旋走滑结构。研究区内有走滑盆地和伸展盆地两种类型:前者位于走滑断裂带内部,近似平行于走滑断裂带展布,走滑作用强,构造反转明显;后者位于走滑断裂带端部,与走滑断裂带斜交,伸展作用强,构造反转较弱。中非裂谷盆地发育3期裂陷—拗陷构造旋回:早白垩世,中非盆地同时发生强烈的裂陷作用;晚白垩世,不同空间位置盆地的裂谷作用强度差异明显并且经历构造反转;古近纪,只有近NW-SE向盆地发生第三期裂谷作用,而其他盆地处于拗陷期。中非裂谷盆地是非洲陆缘板块构造运动在非洲陆内3个块体差异应力作用的陆内响应,3期裂谷作用的构造动力来源不同:早白垩世中大西洋扩张、晚白垩世南大西洋快速扩张和印度洋扩张双重作用、古近纪非洲板块与欧洲板块主要碰撞及西北印度洋中脊扩张影响。 相似文献