First-passage time densities and quantiles are important metrics in performance analysis. They are used in the analysis of mobile communication systems, web servers, manufacturing systems as well as for the analysis of the quality of service of hospitals and government organisations. In this report we look at computational techniques for the first-passage time analysis on highlevel models that ...

Operational systems consist of components that deteriorate and eventually fail. Upon failure, components are either repaired or replaced. Cheap and critical components are usually replaced, while expensive and non-critical components are repaired several times before complete replacement. In this research work, repairable systems undergoing imperfect repair are examined. In this type of repair,...

The power law process has proved to be a useful tool in characterizing the failure process of repairable systems. This paper presents a procedure for detecting and estimating a mixture of conforming and nonconforming systems. The test of a mixture, based on a simple likelihood ratio, is illustrated with truncated failure data for copy machines. Bootstrap methods are used to gauge the estimation...

this paper presents the steady state behavior and maintenance planning of the bleaching system in a paper plant. the paper plant comprises of various systems including feeding, chipping, digesting, washing, bleaching, screening, stock preparation and paper making, etc. one of the most important functionaries of a paper plant, on which quality of paper depends, is the bleaching system, where rem...

This paper introduces a simple index that helps to assess the degree of aging or rejuvenation of repairable systems. The index ranges from -1 to 1. It is negative for the point processes with decreasing ROCOF and is positive for the point processes with increasing ROCOF. Index Terms aging, rejuvenation, homogeneity, non-homogeneity. ACRONYMS CDF cumulative distribution function CIF cumulative i...

Denoising of real world images that are degraded by Gaussian noise is a long established problem in statistical signal processing. The existing models in time-frequency domain typically model the wavelet coefficients as either independent or jointly Gaussian. However, in the compression arena, techniques like denoising and detection, states the need for models to be nonGaussian in nature. Proba...

Kijima and Sumita have proposed a stochastic model called the generalized renewal process (GRP) to describe the availability characteristics of repairable systems by introducing the notion of the virtual age of the system. Yanez et al. offer maximum likelihood estimation (MLE) approach for estimating parameters of the GRP models. Due to the complexity of the equations, a close solution is not a...

We study networks of biochemical reactions modelled by continuous-time Markov processes. Such networks typically contain many molecular species and reactions and are hard to study analytically as well as by simulation. Particularly, we are interested in reaction networks with intermediate species such as the substrate-enzyme complex in the Michaelis-Menten mechanism. These species are virtually...

In recent years the EU has been increasingly involved in development and implementation of crisis policy as a component of its development and security policy. This process is seriously complicated by the EU architects, who had never conceived it as a crisis management institute. Therefore they failed to design built-in organisational capacities into the Union to mitigate and respond to crises....