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Shallow Underground Space Exploration and IoT Security Monitoring

Underground space development intensity is roughly positively related to city scale. At present, underground development depth is about 20 meters in our small cities and 50-70 meters in first-tier cities. Some special projects will have deeper development. The 2014 China Urban Underground Space Development Report White Paper points out: utilization of urban underground space has become a worldwide development trend, and even an important criterion for measuring urban modernization [1]. China has incorporated "deep land" (that is, the development and utilization of underground space) into the national strategy and major scientific and technological plan for the expansion of territorial space in the "13th Five-Year Plan" outline. To explore deep earth, seek space, resources and safety therefrom, and break through the predicament of urban development, pioneering exploration into the potential and development methods of underground space resources is required [2]. At the same time, security and stability issues exist in underground space. Fine exploration of underground space and reasonable monitoring via Internet of Things are of great significance for better and safe use of underground space.