A Retrial Inventory System with Non-Preemptive Priority Service

摘要

本文討論有兩類顧客的排隊-庫存系阵。高優先權和低優先權的顧客到達系統的過 程是泊松過程，服務時間服從指數分佈，庫存供貨策略是(s;S)策略。供貨時間服從指 數分佈。只有低優先權的顧客可以重審服務，重審時間服從指數分佈。我們得到平穩狀態 下排隊顧客的聯合概率分佈、重審的顧客數、庫存水平等行爲指標。數值例子分析了系 統的參數及成本對這些指標的影響。%We consider a queueing-inventory system with two types of customers, say, high priority and low priority, arrive according to Poisson processes. The service times are exponentially distributed. The inventory is replenished according to an (s, S) policy and the replenishing times are assumed to be exponentially distributed. Retrial is introduced for low priority customers only. The orbiting customers compete for service by sending out signals that are exponentially distributed. The joint probability distribution of the number of customers in the waiting area, the number of customers in the orbit and the inventory level is obtained for the steady state case. Some important system performance measures in the steady state are derived. Several numerical examples axe presented to illustrate the effect of the system parameters and costs on these measures.