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作者：Shanthikumar, JG; Xu, SH
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
摘要：We consider a single stage queueing system with c heterogeneous servers. Customers arrive at this system according to a renewal process with mean 1/lambda and squared coefficient of variation (scv) C-a(2). An incoming customer is routed to server i with probability theta(i), Sigma(i=1)(c) theta(i) = 1. The service times at servier i are i.i.d random variables mean 1/mu(i) and scv C-Si(2). The holding cost rate of queue i is h, per customer. i = 1,2,...,c. The problems of interest are twofold: ...
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作者：Bertsimas, D; Mourtzinou, G
作者单位：Massachusetts Institute of Technology (MIT)
摘要：We propose a new approach to analyze multiclass queueing systems in heavy traffic based on what we consider as fundamental laws in queueing systems, namely distributional and conservation laws. Methodologically, we extend the distributional laws from single class queueing systems to multiple classes and combine them with conservation laws to find the heavy traffic behavior of the following systems: (a) Sigma GI/G/1 queue under FIFO. (b) Sigma GI/G/1 queue with priorities, (c) Polling systems w...
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作者：Fisher, ML; Jornsten, KO; Madsen, OBG
作者单位：Norwegian School of Economics (NHH); Technical University of Denmark
摘要：We describe two optimization methods for vehicle routing problems with time windows. These are a K-Tree relaxation with time windows added as side constraints and a Lagrangian decomposition in which variable splitting is used to divide the problem into two subproblems-a semi-assignment problem and a series of shortest path problems with time windows and capacity constraints. We present optimal solutions to problems with up to 100 customers.
