A multi-server queueing system with two types of requests and preemptive priority one type is considered as a model cell cognitive radio under practical suggestions about the arrival flows. hysteresis strategy for server reservation suggested to mitigate effect interruption service low requests. Under arbitrarily fixed values sets thresholds defining this strategy, behavior described by level-d...

The current generation of object-relational databases can support complex data types including multimedia types. This paper describes some of the challenges and opportunities facing OR-DBMS technology in the web environment. The PREDAT OR project at Cornell is actively exploring some of these issues. We present initial directions that suggest that several standard system design and implementati...

This paper investigates the network location problem for single-server facilities that are subject to congestion. In each network edge, customers are uniformly distributed along the edge and their requests for service are assumed to be generated according to a Poisson process. A number of facilities are to be selected from a number of candidate sites and a single server is located at each facil...

This investigation deals with single server queueing system wherein the arrival of the units follow Poisson process with varying arrival rates in different states and the service time of the units is arbitrary (general) distributed. The server may take a vacation of a fixed duration or may continue to be available in the system for next service. Using the probability argument, we construct the ...