Some sharp bounds and simple approximations are obtained for the Erlang delay formula and for the Erlang loss formula. One of the results is then used to get a simple analytical solution for the Server Allocation Problem.

In this paper we consider perishable inventory systems with two types of demand. Demand may be for either fresh items or for somewhat older items. We model the system with two inventory stages. The first stage holds fresh items and the second stage holds the older items. We approximate the...

A cyclic queue has one server and n nodes, where each node has its own distinct type of customers that arrive from the outside. The server visits the nodes cyclically, serving the customers first at node 1, then at node 2, and so on through node n, and then repeating from node 1 again. Setup...

Call center managers are facing increasing pressure to reduce costs while maintaining acceptable service quality. Consequently, they often face constrained stochastic optimization problems, minimizing cost subject to service-level constraints. Complicating this problem is the fact that...

Simple inequalities are obtained for some operating characteristics of multiserver queueing models. "Loss system" and "delay system" results are presented.

The problem of simultaneous due-date setting and priority sequencing is analyzed in the setting of a multiclass M/G/1 queueing system. The objective is to minimize the weighted average due-date lead time (due-date minus arrival date) of jobs subject to a constraint on either the fraction of...

We develop a methodology for studying ''large deviations type'' questions. Our approach does not require that the large deviations principle holds, and is thus applicable to a larg class of systems. We study a system of queues with exponential servers, which share an arrival stream. Arrivals are...

We explore the issues of when and how to partition arriving customers into service groups that will be served separately, in a first-come first-served manner, by multiserver service systems having a provision for waiting, and how to assign an appropriate number of servers to each group. We...

We empirically explore the accuracy of the simple stationary peak hour approximation (SPHA) for estimating peak hour performance in multiserver queuing systems with exponential service times and periodic (sinusoidal) Poisson arrival processes. We show that the SPHA is very good for a range of...

We consider the problem of simultaneously allocating servers and demands in a service system with independent multiple facilities. We assume a fixed number of facilities and total servers which must service a given Poisson arrival stream. We also assume that service times are identically...