In order to analyze the content characteristics of international occupational health policies and promote the high-quality development of China's occupational health career，the occupational health policy texts of five countries，namely China，the United States，Japan，Australia，and Sweden，were taken as the research object. Relying on theory of policy tools and PMC index model，a quantitative analysis of the occupational health policies of the five countries was conducted under the international comparative perspective，and suggestions for optimizing China's occupational health policies were then put forward. The study shows that the five countries tend to shape the macro-environment and human and material resources of occupational health governance through environmental and supply-side tools and neglect the pulling role of demand-side tools. Compared with other countries，China has an excellent performance in terms of policy nature，policy recipients，policy focus，and incentives and constraints，and there is still some room for development in terms of policy effectiveness，policy perspectives，and policy subjects. Enhanced comprehension of the issue concerning the imbalanced allocation of occupational health policy tools is imperative. In light of the intricate and dynamic characteristics inherent in managing occupational health for workers，the imperative lies in providing enhanced guidance and support，particularly to those susceptible to mental health hazards.

To explore the enhanced permeability of gas-containing coal seams and improve extraction efficiency，high-pressure gas fracturing tests under different impact directions were performed by a self-developed true triaxial high-pressure gas impact rock fracturing test system. The test variable was the angle between gas impact direction and maximum horizontal principal stress. High-pressure gas impact tests were performed under the actions of three triaxial stress，and rock fracture morphology and acoustic emission response were obtained at angles between the impact direction and the maximum horizontal principal stress of 0，30，45，60，and 90°. The results indicated that the rock fracturing process caused by high-pressure gas presented five significant stages including the impact crack initiation stage，air pressure rising stage，crack propagation stage，air pressure stabilization stage，and pressure attenuation stage; High-pressure gas impact caused vertical and horizontal cracks. Vertical cracks were deflected，and the deflection angle increased with the increment of the jet angle. Moreover，the crack deflection points gradually moved away from the drilling hole，and the horizontal fracture surface took on a shape of low in the middle and high in surrounding areas. The maximum gas pressure increased with the angle between the jet direction and the maximum principal stress，and the peak pressure represented a linear increment from 0 to 90°; The acoustic emission signals analysis indicated that rock impact failure was primarily caused by tensile failure and supplemented by shear failure. However，as the jet angle increased，it gradually became a tensile-shear composite failure dominated by shear failure.

In order to address the inefficiencies in manually classifying and analyzing inspection records about civil aviation supervision，a dual-channel feature extraction short text classification model was proposed. The model combined data augmentation techniques and character-word vector fusion. The model aimed to tackle classification issues related to people，equipment and facilities，institutional procedures and institutional responsibilities in civil aviation supervised matters. In order to tackle the issue of class imbalance，data augmentation algorithms were employed to generate new samples by transforming the original texts，thereby balancing the sample sizes across different categories. The word vectors and character vectors were fused by combining them at the character level，resulting in character vectors that retain word-level features. These fused character vectors were then fed into TextCNN and BiLSTM for feature extraction at different dimensions. By extracting features from both local and global perspectives，this dual-channel approach aimed to capture comprehensive and effective information from the inspection records dataset in civil aviation regulatory matters. Experimental results on the civil aviation regulatory matter inspection record dataset demonstrate that the proposed model achieves an accuracy of 0.983 7 and an F₁ score of 0.983 6. Compared with some existing word embedding models and character embedding models，the accuracy is improved by 0.4%. Furthermore，when compared with commonly used single-channel models，the accuracy is increased by 3%，which validates the effectiveness and comprehensiveness of the features extracted by the dual-channel model.

In order to effectively prevent and control the key safety risks in subway shield tunneling construction and accurately judge which risk coupling scenarios were significant ones leading to accidents，an improved N-K model was proposed to study the coupling effect of safety risks in subway shield tunneling. The key safety risks of subway shield tunneling were identified by comprehensively using literature research，accident case analysis and expert interview. Based on the N-K model，a new coupling analysis model of subway shield tunneling safety risk was proposed，and the applicability of the model was verified by a safety accident case. The results show that the list of key safety risk factors of subway shield tunneling is obtained，including 4 first-level risk factors (i.e.，personnel-type，equipment-type，environment-type and management-type safety risks) and 21 second-level risk factors. The safety risk value of subway shield tunneling construction increases with the increase of coupling factors. Safety risk coupling values with four factors are the highest，followed by the coupling values of three factors，and safety risk coupling values with two factors are the lowest. Coupling scenarios with workers' low safety awareness and machine failure participating are more susceptible to safety accidents.

In order to improve the economic benefits of coal mining enterprises and reasonable arrangement of various safety inputs，a model to solve the correlation between indicators was constructed. Firstly，the influencing factors of economic benefits based on safety investment were analyzed，and a set of scientific and reasonable structural index systems was constructed on this basis. Secondly，the entropy weight method was used to determine the weight of each index. Then，in view of the correlation between indicators，based on the safety input structure，the entropy weight-Choquet fuzzy integral model based on a 2-additive fuzzy measure was introduced to calculate the economic benefit evaluation value. Finally，a coal mine was selected for empirical analysis to verify the feasibility and effectiveness of the constructed model. The results show that the constructed model is more reliable than technique for order preference by similarity to an ideal solution(TOPSIS) method. This model can take into account the mutual influence and correlation between indicators and obtain more accurate and scientific evaluation results.

To improve coalbed methane extraction efficiency in deep mines，a high-flow sealing hole grouting material was developed using superfine cement as the base material to overcome issues of commonly used high polymer sealed materials such as high cost and flammable，low permeability of ordinary cement materials，and insufficient strength of paste materials such as fly ash. The hydration mechanism of the developed high-flow sealing grouting material was explored by an experimental study on the material's mechanical properties，combined with the measurements by scanning electron microscope(SEM)and X-ray diffraction(XRD). The results indicated that a large amount of calcium silicate hydrate (C-S-H) gel and ettringite (AFt) crystals were generated in the high-flow sealing grouting material during the initial phase of hydration. Furthermore，the gel particles of hydration products filled the pores of the material with the hydration reaction. Compared to commonly used cement sealing grouting material，the hydration reaction of the developed material was much faster and more complete，and the overall structure was more denser. Moreover，the compressive strength was increased by 3.68%. Therefore，the developed high-flow sealing hole grouting material can maintain the stability of gas extraction boreholes and improve gas extraction efficiency.

In order to understand the influences of personality traits behind drivers' unsafe driving behavior，relevant studies on the relationship between personality traits and driving behavior at home and abroad since 2000 were reviewed. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) standard，17 688 articles were retrieved from well-known domestic and foreign databases. After removing 3 160 duplicate articles，14 263 irrelevant articles and 198 non-excellent articles，67 excellent articles were finally included in this study. The relationships between different personality traits and unsafe driving behavior in these articles were summarized and sorted out. The results show that the five personality dimensions of the Big Five personality have different relationships with driving behavior. While sensation-seeking and impulsivity are both strong predictors of unsafe driving behavior，the latter has a stronger predictive ability. The direct predictive ability of driving anger on unsafe driving behavior is not strong. Additionally，factors such as normlessness，trait anxiety，altruism and narcissism have influence on unsafe driving behavior，although there is limited research on these. Furthermore，attachment，trait emotional intelligence，collectivism and abnormal personality traits need more tests. Some research results from Chinese samples diverge from the broader body of research，suggesting a need for cross-cultural studies.

In order to explore the mechanism of the influence of work underload on the risk perception ability of coal mine monitoring inspectors，boredom proneness and mind wandering were introduced as mediating variables to construct a chain mediation model of the four. A structured questionnaire was made with four scales: work underload，boredom proneness，mind wandering and risk perception. Quantitative studies were conducted on questionnaire samples from 263 coal mine monitoring inspectors，and the sample data were analyzed using Pearson correlation analysis and mediation effect tests. The results show that work underload has a direct negative effect on the risk perception ability of coal mine monitoring inspectors. Furthermore，work underload also affects risk perception through the independent mediating effects of boredom proneness and mind wandering，and the chain mediating effect of boredom proneness and mind wandering. Therefore，timely detection and intervention of work underload，boredom proneness and mind wandering of inspectors can effectively improve their risk perception ability and prevent accidents.

In order to explore the spatial and temporal evolution characteristics of fire，economy and environment，based on the data of fire，economy and environment in China from 2000 to 2019，a fire-economy-environment coupling coordination model was established to study the coupling development level of fire，economy and environment system. Combined with ESDA method，the spatial and temporal evolution characteristics and aggregation of each subsystem in 31 provinces were studied，and the spatial correlation analysis of fire，economy and environment was carried out based on Moran 'I test. The research shows that the comprehensive development of fire，economy and environment has been well coupled from 2000 to 2019. From the time dimension，the coupling degree and coordination degree showed an upward trend from 2000 to 2019. The coupling degree was affected by the fire comprehensive score，and the coordination degree was affected by the economic subsystem. From the spatial dimension，economic development is the main factor affecting the coupling coordination degree of 31 provinces. From the analysis of the spatial and temporal evolution of the coupling relationship，the provincial coupling degree is aggregated with time，and the coupling coordination degree is random in spatial aggregation. The different effects of fire，economy and environment on coupling coordination lead to different coordination types and spatial aggregation states.

The double prevention mechanism was a widely used risk control system in hazardous chemical fields in China. However，the theoretical framework at underlying and operational levels was missing. Especially，there was a lack of RCA results to guide double prevention. Therefore，VPSB model was proposed by integrating primary-secondary barrier theory and ECF analysis technology. Furthermore，ECF as a typical RCA method represented the causal of a catastrophic event composed of specific primary-secondary barrier failure modes，providing a visualized diagram for the VPSB model. The model was used to identify hazards and RCA for a typical accident scenario in the Texas explosion of British Petroleum(BP) company. Moreover，the failure modes of double prevention related to management measures were investigated. The comparisons of investigation results between the U.S. Chemical Safety Board (CSB) and BP indicated that people's unsafe actions were taken as the direct cause to carry out in-depth cause analysis. Moreover，the focus was human management，and the failure of the safety supervisors and irregular operations of the operators were macroscopically summarized as the root causes. However，the VPSB model focused on near-miss and the process of major accident hazards，and detailed sub-barrier failure modes were used to highlight the fundamental problems of management systems. Specifically，mechanical integrity management had the largest number of problems because management measures were not conducted as required. This study can provide rectification directions and operability recommendations for enterprises to optimize the relevant work content of the double prevention mechanism.