A free trade zone is an isolated, closed area, usually adjacent to a sea port.

保税区是个孤立、封闭的区域，经常濒临海港。

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For modeling customs checkpost area on free trade port area, a discrete event simulation model was built by the analysis on queuing network, characteristics of customs supervision and traffic flow.

针对保税港区海关卡口区域的建模问题，从海关监管、交通特征及排队网络分析出发建立了其离散事件仿真模型。

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