In order to investigate the spatio-temporal evolution of mining-induced fissures and change characteristics of pressure relief gas-enriched area in the overlying rock of the slowly inclined coal bed，physical similarity simulation and field monitoring method were used to analyze the evolution and distribution characteristics of the fissure in the overlying rock. The evolution characteristics of the pressure relief gas-enriched area were studied to determine the parameter arrangement scheme of the high directional drilling holes，and the effect test was carried out. The results show that the test working face has a height of 13 m along the caving zone of the coal bed，and the height of the fissure zone is 68.5 m. The fissure network along the working face is affected by the inclination angle of the coal bed，and the fracture angle of the working face is 54°-59°. The openness of the fissure development is gradually increasing upward from the working face，and the gas transportation channel is asymmetric. The whole life cycle of the gas extraction process by high directional drilling can be divided into the early stage of extraction，the middle stage of extraction，and the end stage of extraction according to the extraction volume fraction. In the early stage of extraction，the volume fraction is low. The middle stage of extraction has high efficiency in the whole life cycle of extraction. In the late stage of extraction，the volume fraction shows a sharp decline. After the implementation of the high directional and long drilling technology，the volume fractions of the gas in the upper corners of the working face and in the return-air tunnel are all less than 0.8%，indicating a good effect of the gas extraction，and the arrangement of the high drilling holes is reasonable.

To study the damage characteristics of the circular chain of the scraper conveyor，a mathematical model was constructed for the sliding and rubbing wear and vibration impact damage of the circular chain for different damage modes. By using finite element analysis software to simulate and analyze the sliding and rubbing damage between chain links and that between the chain link and the middle groove，as well as the vibration impact damage during the circular chain transmission process，the damage characteristics of circular chains were explored. The research results indicate that under the simulation of sliding and rubbing damage between the chain link and the middle groove，the maximum force on the bottom of the chain link is 65.92 MPa，and the maximum wear depth is 0.55 mm. Under the simulation of sliding and rubbing damage between chain links，the maximum force at the chain link socket is 164.8 MPa. Under the simulation of vibration impact damage of chain links，the maximum stress value on the chain link gradually increases from 39.11 MPa to 52.61 MPa.

In order to detect the spontaneous combustion of coal gangue in open-pit mines in time and avoid greater losses caused by the spread of fire，the technology of spontaneous combustion and fire detection in open-pit mines based on infrared thermal imaging and deep learning was studied. As a result，the problem that a single detection method cannot achieve all-round spontaneous combustion and fire detection of coal gangue in large open-pit mines was solved. First，it was proposed to realize spontaneous combustion and fire detection in different areas through infrared thermal imaging and fire image target recognition，and a spontaneous combustion recognition of coal seam and early warning system architecture of open-pit mines was built. Then，thermal imaging equipment fixed on the ground of the open-pit mine was used to capture infrared images of the coal gangue area where no fire has occurred in real time and monitor the temperature changes of the coal gangue. Finally，the drone with an airborne camera was used to take photos of coal seams，waste piles，and surrounding environments，and then a fire detection model was built through the YOLOv8 target detection algorithm based on deep learning，so as to realize the detection of image targets of flames and smoke，thereby completing fire detection and early warning. The results show that the joint detection technology based on thermal infrared images and flame and smoke image recognition has an average detection accuracy of 70.5% for flames and an average recognition accuracy of 74% for smoke，which can meet the detection needs of spontaneous combustion and fire in open-pit mines.

In order to reduce the serious threat of slope sliding and the geologic disasters they cause to property safety，a novel slope sliding monitoring method was proposed by using a matching algorithm based on the improved Harris corner point detection technique. First，an image processing model for predicting slope sliding displacement was constructed by optimizing the Harris corner point detection; then，based on the calibrated template，the changes in the location of the corner points were monitored to accurately estimate the sliding displacement and track its trajectory，so as to effectively monitor the movement of the slope; finally，a modularized test environment was constructed to monitor slope sliding conditions. The results show that the method reduces the generation of pseudo-corner points in slope monitoring and identification，improves the accuracy and efficiency of corner point detection，and effectively records the tiny sliding of the target in the horizontal，vertical，and inclined directions to form trajectory tracking results.

In order to protect the psychological health of heavy-haul locomotive crew and explore the level of psychological health and influencing factors of heavy-haul locomotive crew，a sampling survey was conducted on the health and performance data of locomotive crew. First，the psychological health characteristics corresponding to safety performance were extracted，and psychological standards for the crew were developed. Then，the characteristics of the sampling objects were collected and counted，and influencing factors were analyzed. The results show that the safety attitude and safety thinking of heavy-haul locomotive crew are significantly higher than those of other job groups. At the same time，the psychological state of the heavy-haul locomotive crew is positively correlated with their level of education and negatively correlated with their sleep quality. Meanwhile，conducting psychological state assessments for the heavy-haul locomotive crew is helpful for normalizing psychological health monitoring. By constructing a full-cycle psychological health indicator for key positions，a new method for evaluating the psychological health of heavy-haul locomotive crew is developed，and it can serve as a reference for other industrial and mining enterprises to evaluate the psychological health of key position groups.

To prevent safety accident risks caused by human factors，a comprehensive survey was conducted on the psychological state of frontline operation and maintenance personnel in the new energy wind power industry. Firstly，the evaluation group and method of psychological health state and safety psychology were selected. Then，the current situation and characteristics of psychological health in the industry were summarized. Finally，relevant analyses were conducted from the perspectives of safety climate and team psychological safety. The survey results show that over half of the employees have poor or sub-optimal general psychological health，among which depression is a prominent issue. Employees have a high level of recognition for the company's safety regulations，but their sense of psychological safety within the team still needs to be strengthened. It is recommended to conduct psychological intervention through an employee assistance program to promote psychological health status and team psychological safety.

In order to scientifically assess the firefighting and rescue capability and put forward effective suggestions for the prevention and control of fire risks，a firefighting and rescue capability assessment system applicable to the characteristics of coal chemical enterprises was constructed based on the hierarchical analysis-fuzzy comprehensive model. The scientificity，applicability，and accuracy of the assessment index system and the model were verified through specific cases. The research results show that along with the booming development of China's economy and society，the scope of the firefighting and rescue task gradually presents a trend of diversification and complexity. In this ever-changing environment，whether firefighting and emergency rescue are able to respond decisively，accurately，and efficiently at critical moments is a key issue that needs to be solved in the current research. The assessment index system and the modeling method used can provide a new perspective for the firefighting and rescue capability building of coal chemical industry-related enterprises and provide decision support for firefighting and rescue capability building.

To effectively reduce the occurrence of coal mine accidents，a systematic analysis of key factors contributing to hidden dangers in coal mines was made by integrating grey theory with the decision-making trial and evaluation laboratory (Grey-DEMATEL) approach. By collecting extensive data on coal mine accidents and relevant literature，an indicator system encompassing multiple dimensions of hidden dangers in coal mines was established. Based on actual surveys and expert evaluations，13 hidden danger indicators were constructed. The Grey-DEMATEL approach was then employed for quantitative analysis of these hidden danger factors，enabling the identification of causal and resultant factors associated with hidden dangers. The research findings indicate that the primary causal factors leading to hidden dangers in coal mines include inaccurate information transmission，overdue equipment maintenance，and workers' violations of safety protocols. The resultant factors of hidden dangers comprise equipment failures，environmental issues，and management deficiencies. By introducing grey theory，the improved Grey-DEMATEL model can mitigate the bias in weight calculations commonly found in traditional models，providing more accurate results for the identification and management of hidden dangers in coal mines.

In order to effectively curb accidents，strengthen the guidance and support role of safety theory in power safety production，and overcome the mismatch between foreign theories and existing safety theory models that cannot meet the actual needs of complex power safety production，local characteristic power safety production management theories and models were constructed. Based on various advanced causal chains，causes of accidental energy release accidents，nuclear power protection barriers，and 4M barrier theories in China and abroad，combined with the objective reality of the safety production site of the power generation enterprise of CHN Energy Group and years of risk control experience，the reverse thinking of accidents (accident causes) and the positive thinking of risk pre-control (barrier control) were combined to propose the 4M barrier theory of machine & material，man，medium，and management in safety management of power generation enterprises. Through dynamic modeling，the internal accident evolution roots and prevention and control laws were analyzed，and the internal logical relationships of each element were sorted out. The results show that this theoretical model can provide a relatively systematic and new risk pre-control concept and methodology for power generation enterprises to establish a sound safety production risk management system by clarifying the risk and its barrier control objects and analyzing the accident development process and its causes.

To study the key points of process safety management in chemical infrastructure projects and carry out targeted safety management，the safety inspection of a gasification unit during construction in a chemical project of an energy group was studied. The entire process safety records of the project were collected，classified，organized，statistically analyzed，compared，and inspected. The key and difficult points of project safety management were summarized by comparing the types and quantities of safety hazards in each unit，the number of hazards per contract valuing million yuan，the distribution of various types of safety hazards，the distribution of safety hazards in each unit，and the comparison of safety hazards in similar units. The research shows that safety protection is the type of safety hazards that generate the most hazards during project construction，and reducing the number of such safety protection hazards can effectively improve the level of project safety management. The safety management level of each construction unit varies，and each construction unit has its own management characteristics. The list of qualified contractors should be further improved through contractor evaluation. It is also necessary to establish a qualified contractor database and record the advantages and disadvantages of contractor safety management，so as to facilitate targeted safety management in future projects.