We consider M/G/1 queues with workload-dependent arrival rate, service speed, and restricted accessibility. The admittance of customers typically depends on the amount of work found upon arrival in addition to its own service requirement. Typical examples are the finite dam, systems with customer impatience and queues regulated by the complete rejection discipline. Our study is motivated by que...

This paper presents a statistical characterization of on-line service traffic. The traffic is parameterized by the call holding times, the aggregate number of bytes and the number of packets transferred during the call. Particular attention is paid to modeling the stochastic rate function describing the call arrivals. The time of day and day of the week seasonal features produce long term corre...

We view queue as a service facility and consider the situation when users offer arrival rate at stationarity that depends on the Quality of Service (QoS) they experience. We study the equilibrium points and the equilibrium sets associated with this interaction and their interpretations in terms of business cycles. The queue implements the optimal admission control (either discounted or ergodic)...

We develop and test an integrated forecasting and stochastic programming approach to workforce management in call centers. We first demonstrate that parametric forecasts can be used to drive stochastic programs whose results are stable with relatively small numbers of scenarios. We then extend our approach to include forecast updates and two-stage stochastic programs with recourse and provide a...

This paper analyzes anM/M/2 queueing systemwith two heterogeneous servers, one of which is always available but the other goes on vacation in the absence of customers waiting for service. The vacationing server, however, returns to serve at a low rate as an arrival finds the other server busy. The system is analyzed in the steady state using matrix geometric method. Busy period of the system is...

Tandem queues with finite buffer capacity commonly exist in practical applications. By viewing a tandem queue as an integrated system, an innovative approach has been developed to analyze its performance through the insight from Friedman's reduction method. Fundamental properties of tandem queues with finite buffer capacity are examined. We show that in general system service rate of a dual tan...

Many computer networks such as wireless networks are stochastic in nature. In order to perform performance guarantee analysis of such networks, a theory, called stochastic network calculus, has evolved. In the stochastic network calculus literature, most results are based on space-domain traffic and service models where the arrival process and the service process are respectively characterized ...

Consider a single server queue in which the service station may breakdown according to a Poisson process with rates γ in busy time and γ’ in idle time respectively. After a breakdown, the service station will be repaired immediately and the repair time is assumed to have an exponential distribution with rate δ. Suppose the arrival time has an exponential distribution with rate λ, and the probab...