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With the rapid construction of cities, the traditional development mode of “incremental expansion” has become unsustainable, and refined and advanced spatial “stock tapping” has gradually become a research focus. This paper is based on crawling the study area points of interest (POI) on the Gaode map in July 2019, and using the representative platform of VGI data (spontaneous geographic information data) OpenStreetMap. The analysis is based on the basic points of the division of the urban road. The area method is used to calculate the functional area, the functional area is quantitatively divided, the spatial pattern is qualitatively analyzed, and the accuracy of the division is evaluated. The results show that the overall classification accuracy of functional land in Xi’an’s main urban area is 79.26%, and the Kappa coefficient is 0.748. In general, the functions of each area are clear, and the layout of functional land is more reasonable, which realizes the fine division of functions in the study area and facilitates dynamic updating.

Human embryogenesis includes an integrated set of complex yet coordinated development of different organs and tissues, which is regulated by the spatiotemporal expression of many genes. Deciphering the gene regulation profile is essential for understanding the molecular basis of human embryo development. While molecular and genetic studies in mouse have served as a valuable tool to understand mammalian development, significant differences exists in human and mouse development at morphological and genomic levels. Thus it is important to carry out research directly on human embryonic development. Here we will review some recent studies on gene regulation during human embryogenesis with particular focus on the period of organogenesis, which had not been well studied previously. We will highlight a gene expression database of human embryos from the 4th to the 9th week. The analysis of gene regulation during this period reveals that genes functioning in a given developmental process tend to be coordinately regulated during human embryogenesis. This feature allows us to use this database to identify new genes important for a particular developmental process/pathway and deduce the potential function of a novel gene during organogenesis. Such a gene expression atlas should serve as an important resource for molecular study of human development and pathogenesis.