As CORBA (Common Object Request Broker Architecture) gains popularity as a standard for portable, distributed, object-oriented computing, the need for a CORBA messaging solution is being increasingly felt. This led the Object Management Group (OMG) to specify a Notification Service that aims to provide a more flexible and robust messaging solution than the earlier Event Service. The Notificatio...

We consider a queuing model with the workload evolving between consecutive i.i.d. exponential timers {e q }i=1,2,... according to a spectrally positive Lévy process Yi(t) that is reflected at zero, and where the environment i equals 0 or 1. When the exponential clock e (i) q ends, the workload, as well as the Lévy input process, are modified; this modification may depend on the current value of...

In this chapter, the main principles of the theory of fractals and multifractals are stated. A singularity spectrum is introduced for the random telecommunication traffic, concepts of fractal dimensions and scaling functions, and methods used in their determination by means of Wavelet Transform Modulus Maxima (WTMM) are proposed. Algorithm development methods for estimating multifractal spectru...

We analyze the delay performance of small cell networks operating under random scheduling (RS) and round robin (RR) protocols. Based on stochastic geometry and queuing theory, we derive accurate and tractable expressions for the distribution of mean delay, which accounts for the impact of random traffic arrivals, queuing interactions, and failed packet retransmissions. Our analysis asserts that...

Multi-supplier inventory systems with seasonal demand are investigated via queuing theory methods in the framework of cost approach. Optimal distribution of replenishment orders between suppliers is obtained under assumption of make-to-order strategy. To this end asymptotic analysis of systems behavior is performed. We apply various mathematical tools such as weak convergence and use properties...

This paper introduces a software application that simulates the most common types of queues. It also compares the simulations results with the values that the mathematical model predicts for specific types of queues. Thus, the software we have developed has two academic aspects. The first one applies to its ability to simulate most of the queuing processes that take place in computer networks. ...

BACKGROUND Hospital pharmacy is responsible for controlling and monitoring the medication use process and ensures the timely access to safe, effective and economical use of drugs and medicines for patients and hospital staff. OBJECTIVES This study aimed to optimize the management of studied outpatient pharmacy by developing suitable queuing theory and simulation technique. PATIENTS AND METH...

This paper is an overview of more than forty of the leading tools being used in the field of network performance analysis, modeling and simulation. The purpose of this paper is to inform potential users of trends in the industry by providing an overview of some of the capabilities of each tool. With unique knowledge of the tools available and a solid background in mathematical modeling and netw...