This paper considers an M/G/1 retrial G-queue with general retrial times, in which the server is subject to working breakdowns and repairs. If the system is not empty during a normal service period, the arrival of a negative customer can cause the server breakdown, and the failed server still works at a lower service rate rather than stopping the service completely. Applying the embedded Markov...

Motivated by the need to study traffic incident management, we consider a Markovian infinite server queue that is subjected to randomly occurring shocks. These shocks affect the service of all servers to deteriorate, i.e., increase the service time of all servers, and might also cause other shocks, thus causing further service deterioration. There are a finite number of service levels, zero cor...

In this paper, we discuss a batch arrival bulk service queue with rework for the faculty item, possibility of breakdown, repair, and two kinds multiple vacation different threshold policy. The server serves remaining after repair completion. This type queuing model has lot applications in manufacturing/ production industries. Performance measures stability conditions are obtained. Numerical ill...

lanczos-type algorithms are well known for their inherent instability. they typically breakdown occurs when relevant orthogonal polynomials do not exist. current approaches to curing breakdown rely on jumping over the non-existent polynomials to resume computation. this may have to be used many times during the solution process. we suggest an alternative to jumping, which consists of restarting...

Two-phase M/Ek/1 queueing system with N -policy for exhaustive batch service with gating, and server startups and breakdowns is studied in this paper. The customers arrive individually according to a Poisson process and waiting customers receive batch service all at a time in the first phase and are served individually in the second phase. The server is turned off each time the system empties, ...

Product design is an evolving process which is characterized with creativity and uncertainty. The task management in this process is different from traditional ones because it involves more specific factors such as user specifications, product design specifications, reengineering, design process, and design data. In this article, we aim to analyze product design process with the viewpoint of pr...

Stress grading (SG) layer in cable terminations limits the critical electric field and properties of SG materials are important issues which have to be considered during manufacturing and selecting procedure. In this paper, two different types of (SG) materials are analyzed by both theory and test. According to the applied theory, important parameters as: electrical resistivity, breakdown volta...

quality of service (qos) is an important issue in the design and management of web service composition. qos in web services consists of various non-functional factors, such as execution cost, execution time, availability, successful execution rate, and security. in recent years, the number of available web services has proliferated, and then offered the same services increasingly. the same web ...

service oriented enterprises (soes) are subject to constant change and variation. in this paper, the changes are considered from an economic perspective based on service culture notion. once a change is implemented, the costs of some member services may increase, whereas the costs of some other services may reduce. we construct a game theoretic model trying to capture the possible conflicting i...

This paper studies a batch arrival single server Bernoulli feedback queue with Poisson arrivals, two stages of heterogeneous service with different (arbitrary) service time distributions subject to random breakdowns and multiple vacations with exponential distributed with Mean vacation time . After first-stage service the server must provide the second stage service. However after the completio...