Time synchronization is indispensable for wide area distributed systems including sensor networks, automation systems, and measurement/control systems. Another application is clock distribution, which is indispensable to support continuous information transfer. Because of the increasing demand for more sophisticated applications, it is essential to establish a time synchronization technique tha...

Wireless sensor networks (WSNs) have a wide variety of military and civil applications. The sensor nodes are powered by batteries with limited energy. Hostile or hazardous environments where the sensor nodes are deployed or the sheer number of the sensors prevents replacement or recharge of the batteries. Therefore in WSNs, scheduling of different types of packets is of vital importance to redu...

Many real-world embedded systems employ a preemptive scheduling policy in order to satisfy their realtime requirements. However, most System-Level Design Languages (SLDLs) which were proposed up to now, such as SpecC, do not explicitly support modeling of preemptions. This paper proposes techniques for modeling xed-priority preemptive multi-task systems in the SpecC SLDL. The modeling technique...

In this paper, we analyze a discrete-time preemptive resume priority queue. We consider two classes of customers which have to be served, where customers of one class have preemptive resume priority over customers of the other. Both classes contain customers with generally distributed service times. We show that the use of probability generating functions is beneficial for analyzing the system ...

A purely functional model of computation, called Priority-based Functional Reactive Programming (P-FRP), has been introduced as a new paradigm for building real-time software. Unlike the classical preemptive model of real-time systems, preempted events in P-FRP are aborted and have to restart when higher priority events have completed, making the response time of events dependent on the executi...

Control of queueing systems to maximize profits or welfare has been the subject of numerous papers. The common methods are by setting adequate price and priority regimes (see [10] for a survey of such models). In other cases, the service provider also sets and advertises waiting time standards [1]. The common priority regime is that of (preemptive or non-preemptive) absolute priorities, where t...

This paper considers general (single facility) queueing systems with exponential service times, dealing with a finite number J of distinct customer classes. Performance of the system, as measured by the vector of steady state expected sojourn times of the customer classes (the performance vector) may be controlled by adopting an appropriate preemptive priority discipline. We show that the perfo...

In this paper we report on a study of a two level preemptive priority queue with balking and reneging for lower priority level. The inter-arrival and the service times for both levels follow exponential distribution. We use a finite difference equation approach for solving the balance equations of the governing queuing model whose states are described by functions of one independent variable. H...

Abstract. We consider a two-priority, preemptive, single-server queueing model. Each customer is classified into either a high priority class or a low priority class. The arrivals of the two priority classes follow independent Poisson processes and service time is assumed to be exponentially distributed. A queue-length-cutoff method is considered. Under this discipline the server responds only ...