In this paper we consider a single-server, cyclic polling system with switch-over times and Poisson arrivals. The service disciplines that are discussed, are exhaustive and gated service. The novel contribution of the present paper is that we consider the reneging of customers at polling instants. In more detail, whenever the server starts or ends a visit to a queue, some of the customers waiti...

We consider single-server queues with exponentially distributed service times, in which the arrival process is governed by a semi-Markov process (SMP). Two service disciplines, processor sharing (PS) and random service (RS), are investigated. We note that the sojourn time distribution of a type-l customer who, upon his arrival, meets k customers already present in the SMP/M/1/PS queue is identi...

The MX/G/1 queue with finite waiting room is studied for both the partially rejected model and the totally rejected model. We start by studying the joint distribution of the number of customers at time t and the remaining service time of customer in service. This gives the asymptotic distribution of the number of customers at an arbitrary moment and immediately after a departure. Also the waiti...

We study a first passage time problem for a class of spectrally positive Lévy processes. By considering the special case where the Lévy process is a compound Poisson process with negative drift, we obtain the Laplace-Stieltjes transform of the steady-state waiting time distribution of low-priority customers in a twoclass M/GI/1 queue operating under a dynamic non-preemptive priority discipline....

Customers desire short waiting times whereas service providers want to maximize resources utilization. Long waiting time is not uncommon in many service organizations and it is familiar especially in outpatient departments. To make the study more realistic, some assumptions were removed and uses an animated simulation model for a mixed-patient type environment in an outpatient department. A spe...

AbstrAct: Muti-objective optimization deals with the simultaneous optimization of two or more conflicting objective functions in real-life systems. This paper deals with the multi-objective optimization in service systems. The goal of service systems is to provide cost-efficient service to customers, while at the same time, reducing the customer waiting time for service. In general, a low cost ...

Introduction The Game The observable case Bibliography The motivation The model The problem The model Infinite waiting space (transportation station) Poisson(λ) customers' arrival process 1 server (bus) Renewal server's visiting process {M (t)} When a server with capacity k visits the system: serves k customers instantaneously, the others abandon the system Introduction The Game The observable ...

With the rise of value–added grains and oilseeds, many elevators need to segregate their incoming products into batches of different end–use quality (for example, high oil corn, genetically modified soybeans, high protein wheat), but often they are not designed to handle this task efficiently. The primary challenge is to segregate multiple grain streams during the receiving operation without in...