It was set up comprehensively as far as Song Dynasty.Dongjing is the most emblematical deputation.

可说，经过隋唐五代逐开放，直到北宋时期，才在城市中有了广泛设置，当时都城东京是最为典型代表。

After the analysis and calculation to an emblematical hypothesis, we made further improvement to the model.The result validated the rationality of the model.

通过典型想定示例计算分析，对模型进行了进改进与探讨，所得结果充分验证了模型合理性。