In the planning of modern cellular mobile communication systems customer behavior has to be carefully taken into account In this paper two models dealing with the call retrial phenomenon are presented The rst model considers a base station with a nite customer population and repeated attempts A Markov chain modeling is proposed and a recursive solution of the state probabilities is presented Th...

In this paper, we investigate the fuzzy logic based system characteristics of M/G/1 retrial queuing system with Bernoulli vacation schedule. The service time and vacation time are assumed to be generally distributed. It is found in many practical situations that the queuing models with fuzzy parameters are much more realistic than the classical crisp parameters based queuing models. We have cho...

Abstract. A batch arrival retrial queue with general retrial times, state dependent admission, modified vacation policy and feed back is analysed in this paper. Arrivals are controlled according to the state of the server. If the orbit is empty, the server takes at most J vacations until at least one customer is received in the orbit when the server returns from the vacation. At the service com...

Two independent Poisson streams of jobs flow into a single-server service system having a limited common buffer that can hold at most one job. If a type-i job (i = 1, 2) finds the server busy, it is blocked and routed to a separate type-i retrial (orbit) queue that attempts to re-dispatch its jobs at its specific Poisson rate. This creates a system with three dependent queues. Such a queueing s...

Retrial systems have been used extensively to model many practical problems in call center, data cloud service computing center and computer network system. This paper deals with a multi-server retrial system the features of imperfect coverage delay reboot. In investigated system, arrivals may not be detected because some fault issues. When this situation happened, is cleared by reboot operatio...