We propose an algorithm to obtain bounds for the steady-state availability using Markov models in which only a small portion of the state space is generated. The algorithm is applicable to models with group repair and phase type repair distributions and involves the solution of only four linear systems of the size of the generated state space, independently on the number of “return” states. Num...

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...

SHiMmer, an active-sensing platform, combines wireless communication with solar energy harvesting to provide long-lasting structural health monitoring (SHM). While reducing the need for post-deployment physical human interaction, the platform must adapt performance to accommodate the energy availability. For example, on sunny days, SHiMmer can perform highly accurate tasks requiring more extens...

This note projects forward into the distant future number of countries existing under regimes different levels economic liberalism by deriving a transition probability matrix from Economic Freedom World data. Naively extrapolating trends 1970-2020 suggests modest majority 165 will be economically free in long-run steady state, with results driven improvements variables associated freedom to tra...

Software rejuvenation is a preventive maintenance technique that has been extensively studied in recent literature. In this paper, we extend the classical result by Huang et al. (1995), and in addition propose a modified stochastic model to generate the software rejuvenation schedule. More precisely, the software rejuvenation models are formulated via the semi-Markov reward process, and the opt...