Nasr, Walid2014-03-142014-03-142008-01-18etd-02012008-115247http://hdl.handle.net/10919/26090Developing equations to compute congestion measures for the general G/G/s/c queueing model and networks of such nodes has always been a challenge. One approach to analyzing such systems is to approximate the model-specified general input processes and distributions by processes and distributions from the more computationally friendly family of phase-type processes and distributions. We develop numerical approximation methods for analysis of general time-dependent queueing nodes by introducing new approximations for the time-dependent first two moments of the number-in-system and departure-count processes.In Copyrightphase type distributiondeparture processqueueing systemstime dependentDissertationhttp://scholar.lib.vt.edu/theses/available/etd-02012008-115247/