In large-scale systems where number of components can approach a million a failure is a significant problem. In this paper authors have presented and analyzed failure data from different large systems. More than 100,000 disks with different interfaces which come from at least four different vendors have been investigated. According to information which one can find in datasheets the annual fail...

Disk arrays (RAID) have been proposed as a possible approach to solving the emerging I/O bottleneck problem. The performance of a RAID system when all disks are operational and the MTTF,,, (mean time to system failure) have been well studied. However, the performance of disk arrays in the presence of failed disks has not received much attention. The same techniques that provide the storage effi...

Software reliability is an important aspect in software engineering enviourment. Software reliability is introduced as failure free operation in specified enviourment. Various studies show that the software reliability is defined in three categories that are improvement, modelling and measurement. In this paper, we will study the reliability metrics to improve the software reliability. Reliabil...

E ffective software can mean software that is low cost, reliable, rapidly developed, safe, or has some other relevant attribute. To determine whether a particular technique is effective, we need a way to measure it. Merely saying that a technique is effective conveys no real information. Instead, we need measurements applied to each software attribute so we can say one technique is more or less...

The National Air Traffic Services (NATS) in London require data on the performance likely to be achieved by the navigation system on board aircraft flying in UK airspace. To that end the performance of three different GPS receiver types (all designed for aviation use) has been examined. This paper details the result of that work. The achieved Mean Time Between Failures (referred to here as “Out...

Web Services are built on service-oriented architecture which is based on the notion of building applications by discovering and orchestrating services available on the web. Complex business processes can be realized by discovering and orchestrating already available services on the web. In order to make these orchestrated web services resilient to faults; we proposed a simple and elegant check...

Flexible manufacturing cells (FMCs) often operate with increasing failure rate due to extensive utilization and wear-outs of equipment. While maintenance plans can eliminate wear-out failures, random failures are still unavoidable. This paper discusses a procedure that combines simulation and analytical models to analyze the effects of corrective, preventive, and opportunistic maintenance polic...

Abstract: In this paper, we study the reliability measures of a repairable system with M operating units, W warm standby units, and R repairmen in which switching failures and reboot delay are considered. It is assumed that there is a significant failure probability q in the switching process. Failure times of an operating unit and of a standby unit are assumed to be exponentially distributed w...

How do you calculate the MTTF (Mean Time To Failure) when you have zero failures? If you use the standard equation for MTTF, which is the ratio of total testing time and the number of failures, you get an answer of infinity. In such cases, you define a confidence level between 0 and 100 and then compute the lower bound chi-square value using two degrees of freedom. The equation for calculating ...

The lifetime of power electronic components is often calculated from reliability reports, but this method can be discussed. We compare in this article the results of various reliability reports to an accelerated ageing test of component and introduced the load-strength concept. Large aluminium electrolytic capacitors are taken here in example in the context of the protection system of LHC (Larg...