optimization of maintenance resources to maximize the system availability is a major concern in different manufacturing systems. therefore, a lot of effort is put to construct optimization models to reach the maximum availability level and to reduce the costs of lack of availability. however, despite these efforts, data uncertainty in the real world problems was neglected in proposed models whi...

As switched networks providing services to end users become more commonplace, integral components of these networks must have an increasing level of dependability. One area of interest is determining the optimal number of network servers required for a switched network application by taking into consideration the characteristics of the network tra c and failure rate of the servers. A stochastic...

During the last decade, a model based technique known as enterprise architecture has grown into an established approach for management of information systems in organizations. The use of enterprise architecture primarily promotes good decision-making and communication between business and IT stakeholders. This paper visualizes a scenario where enterprise architecture models are utilized to eval...

In this paper, we analyze a technique for building a high-availability (HA) cluster system. We propose what we have termed the ‘Selective Replication Manager (SRM),’ which improves the throughput performance and reduces the latency of disk devices by means of a Distributed Replicated Block Device (DRBD), which is integrated in the recent Linux Kernel (version 2.6.33 or higher) and that still pr...

Dynamic Fault Trees in Reliability Engineering. Reliability and availability measures, such as system failure probability during a given mission time and system meantime-between-failures, are often important measures to assess in embedded systems design. There exist several techniques and formalisms for reliability/availability assessment. One such formalism is dynamic fault trees (DFT) [6]. DF...

For many technical systems, their availability is an important characteristic. Examples for systems, where availability is especially relevant, are railway control systems, telecommunication systems, and systems supporting business processes. Outages of such systems often have immediate economic consequences for their users and operators. Due to the economic impact, manufacturers and service pr...

The operation and maintenance is one of the most important territories of the automotive industry. From the mathematical point of view, maintenance is a discrete state space stochastic process without after-effects, so it can be modeled as a Markov-chain. After determination of probability densities of changes of operational states and setting up the transition probability matrix, a matrix-alge...

An IT risk assessment must deliver the best possible quality of results in a time-effective way. Organisations are used to customise the general-purpose standard risk assessment methods in a way that can satisfy their requirements. In this paper we present the QualTD Model and method, which is meant to be employed together with standard risk assessment methods for the qualitative assessment of ...