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Considering the influence of the fixing method of the component in the system on its results in ultrasonic infrared thermography testing, the detection experiments of the cracked plat structure with fixing at one end and fixing at two ends are carried out through different fixing methods of the equivalent structure. The results show that for the same structure to be detected, the more the bounds are fixed, the more the degrees of freedom are restricted, the less ultrasonic energy is dissipated during the inspection process, and the better the inspection effect. The work has positive significance for the selection of detection parameters in ultrasonic infrared thermography testing, helpful to provide some references for it.

The ordovician limestone water inrush accident occurred during the excavation of 8228 working face in Tashan Coal Mine, Tongmei Group. On the basis of comprehensive geophysical exploration above and below the well, in order to find out the development boundary of the water flowing subsided column and the distribution characteristics of the broken body filled in it, and to control the subsided column by Grouting, the development boundary, the influence zone, the cementation of the fractured body and the distribution characteristics of the water flowing subsided column are found out by means of multi-layer and multi-branch surface directional horizontal drilling speed logging, drilling fluid leakage, cuttings logging and logging while drilling, and combined with data statistical analysis. The length and short axis of the collapse column is 410m - 200m, and the broken area is mainly distributed in the right front of the driving head of the belt roadway near the water inrush roadway. The 3d geological modeling of the spatial structure and development characteristics of the collapse column is carried out by using SURPAC software, and the main passageway area, fracture area and secondary fracture area are divided according to the crushing degree of the collapse column filling material. In view of the different zones of the collapse column broken body, the directional horizontal drilling control technology and the three-dimensional block grouting technology are used to construct the separate zones of the grouting technology. The safe mining of the working face is finally realized by the comprehensive treatment of cutting the source and reinforcing the water-flowing collapse column. The comprehensive exploration and treatment technology of directional horizontal drilling multi-branch collapse column provides a good reference for other similar projects.

Due to the short duration, high intensity and sudden intensity of torrential rain, mountain torrents are easily formed in the northern hilly area.The distributed hydrological model is used as the main means of rain-flood forecasting. Rainfall as an important input,its spatial interpolation accuracy and time scale directly affect the forecast results.Therefore, in this paper, the spatial interpolation calculation and analysis of rainstorm process with hourly scale is carried out in the northern hilly area. Taking Licheng district in Jinan as the research area, the spatial interpolation methods, such as IDW,OK and OCK, are used to calculate the spatial interpolation of 16 time-by-time rainstorm processes for 11 typical rainfall with different duration, and the interpolation results are cross-validated and error analysis is carried out.The results show that the accuracy of the collaborative Kriging interpolation considering the elevation is higher in the short duration rainstorm process of the hilly area.

In order to study on mechanism of in-situ stress control on the coal floor damage during deep coal seam mining, the internal relationship among ground stress, mine pressure and floor water inrush was analyzed base on the increasing distribution rule of ground stress with the increasing depth of stratum. It is shown that the stress on the deep coal seam has obvious control effect on the depth of the floor damage and failure through the experimental study and the statistical analysis of the measured data of the mining damage depth of the coal seam floor. And the calculation formula for the depth of the floor failure in the deep seam mining was put forward.

In order to comprehensively improve the digital level of soil and water conservation in Anji County, it is necessary to realize the "one map management" of soil and water conservation by the information sharing and interaction among multiple government departments. With the new generation of information technologies such as big data, digital twin, artificial intelligence and virtual reality, use "11143" as the construction framework, improve the data warehouse of soil and water conservation to achieve "one map management" of the whole life cycle of production and construction projects; monitor soil erosion in real time through satellite remote sensing data and provide early warning and forecasting; and dock with the national "double carbon" strategy to build a carbon sink management system for soil and water conservation. It is expected to be built into a water and soil conservation wisdom management platform that meets multiple business application scenarios such as supervision of production and construction projects, dynamic monitoring and comprehensive management of soil erosion, wisdom decision making and application, and industry promotion services.

In this paper, 18 towns of Jinyun were analyzed. Natural conditions (average elevation, relative height difference, and gully density), socio-economic status(population density, and per capita disposable income), characteristics of soil erosion (area ratio of soil erosion, area ratio of soil erosion above moderate), and the present state of soil and water conservation, (vegetation coverage) were calculated. Self-organizing Feature Maps (SOFM) was used for soil and water conservation regionalization. Through the analysis of the 18 towns in Jinyun, two first-order classes and five second-order types were identified. The results showed that the classification results were consistent with the actual characteristics, and the feasibility of using SOFM for classification of soil and water conservation regionalization has been demonstrated through this study.