Abstract: The reliability analysis of load-sharing m-out-of-n systems where the workload is shared by the remaining working units when a unit fails is proposed in the paper. General expressions are provided for the m-out-of-n system reliability by arbitrary probability distributions of time to failure of units. Simplified methods are given for computing the survivor function in cases when the t...

Long-run average properties of probabilistic systems refer to the average behavior of the system, measured over a period of time whose length diverges to innnity. These properties include many relevant performance and reliability indices, such as system throughput, average response time, and mean time between failures. In this paper, we argue that current formal spec-iication methods cannot be ...

The daily volatility is typically unobserved but can be estimated using high frequent tick-by-tick data. In this paper, we study the problem of forecasting the unobserved volatility using past values of measured volatility. Specifically, we use daily estimates of volatility based on high frequency data, called realized variance, and construct the optimal linear forecast of future volatility. Ut...

The effect of supervisory control on a redundant database unit representing a command and control (C2) system that supports air operations is investigated through simulation. Several supervisory control policies are considered. They authorize restoration and/or routing upon the failure of a server in the system. The performance of the modeled system under these policies is evaluated based on th...

The vibration analysis and condition monitoring technology is based on comparison of measurements obtained with benchmarks suggested by manufacturers or standards. In this case, the references provided by current rules are static and independent of parameters such as age or environmental conditions in which the machine is analyzed. New communication technologies allow the integration of eMainte...

Reliability and availability of the equipment or plants used in construction and civil engineering field is significant issue for all stakeholders. Unexpected breakdown and repairs could cause serious consequences such as extra cost and project period extension. Therefore, it is necessary to study the reliability of the construction equipment and predict the failures in time with a reasonable d...

Reliability models based on Markov chain (Except in queuing systems) have extensive applications in electrical and electronic devices. Here, we consider a k-out-of-n:G system with n parallel and identical elements with increasing failure rates (failure rates are Weibull distributed) and non repairable elements. The failure rate of remaining elements increases when some elements fail. The system...

In most practical cases, during a system failure or downtime, all non-failed components are kept idle. This phenomenon is known as suspended animation (SA). In this paper, we provide a simple and efficient method to compute the availability indices of repairable systems subjected to suspended animation. An important aspect of the proposed method is that it is not restricted to exponential failu...

We assume a Boolean parallel system with exponentially distributed component failure times. In order to maximize the lifetime of the system we consider a repairman with Erlang-k distributed repair time. By extending the classical exponential case k = 1 to k ≥ 2 different repair semantics arise in this context. In the case of restart repair semantics we show that a repairman should have few Erla...

Modeling the reliability of distributed systems requires a good understanding of the reliability of the components. Careful modeling allows highly fault-tolerant distributed data applications to be constructed at the least cost. Failure and repair rates of components are often assumed to be exponentially distributed. This hypothesis is testable for failure rates, though the process of gathering...