單元貨載自動化搬運車倉儲系統 (AVS/RS) 透過自動化導向搬運車搬運、上載及卸載貨物以完成顧客訂單;能夠輕易的改變系統規模及產出量是此倉儲系統的優勢，像是增加貨梯數量以因應大量的顧客需求;論文中的等候網路模型透過封閉式等候網路估算自動化搬運車等待升降貨梯的平均等候時間，並透過開放式等候網路估算訂單在系統中等待自動化導向搬運車的平均等候時間，除此之外，等候網路模型也能提供系統中升降貨梯及自動化搬運車的利用率，以及訂單在系統中所花費的平均時間。
為了檢視理論模型所產出的數據是否合理，我們透過系統模擬進行驗證，並同時分析系統中不同參數對系統表現造成的影響;依據不同的訂單到達率、系統規格、自動化搬運車輛及升降貨梯的數量，此等候網路模型都能提供有效的評估。

Unit-load autonomous vehicle storage and retrieval systems utilize AGV’s for loading and unloading pallets (or boxes) of customer orders. The advantage of this system is flexible to change the system configuration, and the number of lifts and AGV’s to meet different throughputs. This research develops closed and open queuing network models to estimate an average vehicle’s waiting time for a lift vertical movement and an average transaction’s waiting time for a vehicle service. At the same time, the utilization rates of lifts and AGV’s and average transaction cycle time will be assessed. Simulation studies are also provided to validate the analytical models and investigate the system performance based on different system design factors. The proposed queuing network models can be used to estimate the performance of AGV’s and lifts in accordance with the transaction arrival rates, layout configuration, number of AGV’s and Lifts.

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