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The study of historical maps is the basis for understanding the dynamic changes of cities. In this paper, the historical map of Liaocheng ancient city and other data were translated, and GIS technology was used for visual analysis. Meanwhile, combined with the concept of “stratification” in the urban historical landscape, this paper summarizes the historical evolution of the ancient city from multiple dimensions and explores the factors affecting its development in order to realize the sustainable development of Liaocheng ancient city.

Aiming at the current status of BDS release of integrity indicators, this paper studies and proposes modeling and qualitative analysis methods for BDS Signal-In-Space(SIS) integrity indicators, which can be used for the allocation and prediction of integrity indicators during system development and construction; The BDS basic navigation service (RNSS) space signal integrity parameter design has proposed a quantitative evaluation method, which can be used for the integrity index test evaluation of the system operation phase. The test results show that the integrity of the new signal of the BDS is 100%.