Fitting the Pht/Mt/s/c Time-Dependent Departure Process for Use in Tandem Queueing Networks

  • Authors:
  • Walid W. Nasr;Michael R. Taaffe

  • Affiliations:
  • Olayan School of Business, American University of Beirut, Riad El-Solh/Beirut 1107 2020, Lebanon;Department of Industrial and Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061

  • Venue:
  • INFORMS Journal on Computing
  • Year:
  • 2013

Quantified Score

Hi-index 0.00

Visualization

Abstract

This paper considers time-dependent Pht/Mt/s/c queueing nodes and small tandem networks of such nodes. We examine characteristics of the departure processes from a multiserver queueing node; in particular, we focus on solving for the first two time-dependent moments of the departure-count process. A finite set of partial moment differential equations is developed to numerically solve for the departure-count moments over specified intervals of time [ti, ti + τi). We also present a distribution fitting algorithm to match these key characteristics with a $\widetilde{Ph_t}$ process serving as the approximate departure process. A distribution fitting algorithm is presented for time-dependent point processes where a two-level balanced mixture of Erlang distribution is used to serve as the approximating process. We then use the $\widetilde{Ph_t}$ approximating departure process as the approximate composite arrival process to downstream nodes in a network of tandem queues.