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Active fault diagnosis based on stochastic tests

Niels K. Poulsen, Henrik Niemann (2008)

International Journal of Applied Mathematics and Computer Science

The focus of this paper is on stochastic change detection applied in connection with active fault diagnosis (AFD). An auxiliary input signal is applied in AFD. This signal injection in the system will in general allow us to obtain a fast change detection/isolation by considering the output or an error output from the system. The classical cumulative sum (CUSUM) test will be modified with respect to the AFD approach applied. The CUSUM method will be altered such that it will be able to detect a change...

Advances in model-based fault diagnosis with evolutionary algorithms and neural networks

Marcin Witczak (2006)

International Journal of Applied Mathematics and Computer Science

Challenging design problems arise regularly in modern fault diagnosis systems. Unfortunately, the classical analytical techniques often cannot provide acceptable solutions to such difficult tasks. This explains why soft computing techniques such as evolutionary algorithms and neural networks become more and more popular in industrial applications of fault diagnosis. The main objective of this paper is to present recent developments regarding the application of evolutionary algorithms and neural...

An application of nonprarametric Cox regression model in reliability analysis: a case study

Petr Volf (2004)

Kybernetika

The contribution deals with an application of the nonparametric version of Cox regression model to the analysis and modeling of the failure rate of technical devices. The objective is to recall the method of statistical analysis of such a model, to adapt it to the real–case study, and in such a way to demonstrate the flexibility of the Cox model. The goodness-of-fit of the model is tested, too, with the aid of the graphical test procedure based on generalized residuals.

An Extended Opportunity-Based Age Replacement Policy

Bermawi P. Iskandar, Hiroaki Sandoh (2010)

RAIRO - Operations Research

The present study proposes an extended opportunity-based age replacement policy where opportunities occur according to a Poisson process. When the age, x of the system satisfies x < S for a prespecified value S, a corrective replacement is conducted if the objective system fails. In case x satisfies S ≤ x < T for another prespecified value T, we take an opportunity to preventively replace the system by a new one with probability p, and do not take the opportunity with probability 1 - p. At...

Analysis of a two-unit standby redundant system with three states of units

Antonín Lešanovský (1982)

Aplikace matematiky

A cold-standby redundant system with two identical units and one repair facility is considered. Units can be in three states> good (I), degraded (II), and failed (III). We suppose that only the following state-transitions of a unit are possible: I I I , I I I I I , I I I , I I I I . The repair of a unit of the type I I I can be interpreted as a preventive maintenance. Its realization depends on the states of both units. Several characteristics of the system (probabilities, distribution functions or their Laplace-Stieltjes transforms...

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