In order to improve the safety and intelligence level of forklift truck，a forklift stability warning method based on multi-core parallel digital twin is proposed. First，the open-source high-precision inertial navigation sensor is used to evaluate the driver's operating habits and road smoothness，and then drive the digital twin operation. Secondly，the optimization algorithm is used to calculate the limit operating parameters that meet the stability conditions，such as the highest load and the fastest driving speed. Then，two acceleration strategies are proposed，which use the open source C language compiled solver and multi-core Central Processing Unit (CPU) in parallel，to shorten the optimization iteration time. Finally，taking a forklift truck as the test object，the accuracy of the measurement of the flight control system is verified，and the real-time performance of the digital twin stability early warning method is analyzed. The results show that the flight control system has high monitoring accuracy，the theoretical calculated values are basically consistent with the collected values，and the longitude and latitude deviation of global positioning system (GPS) is about 1 m. The digital twin program has a faster prediction speed. The digital twin compiled by the open source C language is 3 times faster than the Simulation X3.8 platform，and the parallel digital twin method is 20 times more efficient than the simulation platform.

In order to avoid the accident of CO poisoning in coal mines，according to the principle of adsorption catalysis，CuCl-CeO₂，a composite CO scavenger with both adsorption and catalytic properties，was prepared by thermal dispersion method using rare earth oxide CeO₂ as catalyst carrier and CuCl as adsorbent. The CO elimination performance of CuCl，CeO₂ and CuCl-CeO₂ was studied by cone calorimeter. At the same time，the peak pressure of gas explosion and the CO elimination effect of CuCl-CeO₂ were studied by a 20 L explosion ball-gas chromatography system. The results show that the CuCl-CeO₂ composite scavenger can effectively reduce the release rate of CO during the whole heating process，and its elimination performance is better than that of CuCl or CeO₂ alone. When the mass fraction of CuCl is 50 %，the CO elimination rate of CuCl-CeO₂ is the highest，reaching 88.0 %. With the increase of CuCl-CeO₂ mass concentration，the peak pressure of gas explosion gradually decreases，the time to reach the peak pressure of explosion is significantly delayed，and the amount of CO released is also decreasing. When the mass concentration of CuCl-CeO₂ is 1.00 g/L，the effect of explosion suppression and CO elimination is the best. The peak pressure of gas explosion is reduced from 0.508 MPa to 0.387 MPa，the time to reach the peak pressure of explosion is delayed from 237.6 ms to 483.2 ms，and the volume fraction of CO is reduced from 0.879 7% to 0.108 9%，which effectively reduces the peak pressure of gas explosion and CO release.

In order to investigate the effect of EA on the process of coal oxidation spontaneous combustion，EA was uniformly mixed with long-flame coal in Xiashijie at the mass ratios of 2%，4%，6%，8% and 10% to experiment. The contents of active functional groups and the variation characteristics of thermal transport characteristics of each sample were studied using the microscopic infrared spectroscopy test and laser thermal conductivity test. The optimal mass ratio was determined to be 8% through the evaluation of the inhibitory effect of coal oxidation spontaneous combustion. The coal spontaneous combustion temperature-programmed test was used to compare the influence of four inhibitors on the gas release of coal oxidation spontaneous combustion，and the degree of inhibition of EA on coal oxidation spontaneous combustion was further determined. The results showed that the peak areas of -CH₃，-CH₂，-OH and -C=O- in EA-tc are reduced，but the peak area of C-O is increased compared with RC. At the same coal temperature，the thermal diffusivity and thermal conductivity of the RC are higher than those of EA-tc，and its specific heat is lower than those of EA-tc. The average inhibition rates of thermal diffusivity，specific heat capacity and thermal conductivity of 8% EA on low-temperature oxidation process of coal samples are 20.8%，9.8% and 13.1%，respectively. Compared with RC，CO release amount of 8% EA-tc is reduced by 52.3% at 170 ℃，and the resistance rate of EA on coal oxidation spontaneous combustion is maintained at 50.5% to 72.5% at 30 to 170 ℃. The inhibitory effect of EA on coal oxidation spontaneous combustion is better than that of the other three inhibitors.

In order to achieve a quantitative evaluation of individual pilot's exceedance risk，a refined evaluation model for pilot's individual exceedance risk was established based on QAR data and the flight operations quality assurance(FOQA) monitoring items. Firstly，according to accident statistics，International Civil Aviation Organization (ICAO) and the core risks divided by the FOQA station，the FOQA monitoring items associated with the three types of core risks were selected as the evaluation indexes，and the risk value for each core risk of the individual pilots was calculated. In the next step，the weight of each core risk value was calculated by entropy weighted TOPSIS. Then，the refined evaluation model for the pilot's individual exceedance risk was established. Finally，the model was applied to the quantitative evaluation of actual flight risk. By collecting 9 317 pieces of multi-source fusion data from the FOQA station of Civil Aviation Administration of China (CAAC)，the individual exceedance risk of the pilots were quantified，the ranking of individual pilots' exceedance risk was obtained，and the pilot's individual exceedance risk levels were also divided with the use of K-means clustering algorithm. The results show that the model can quantify and rank 1 693 individual pilots' exceedance risk，and divide the pilot's exceedance risk into three types，including high risk，medium risk and low risk.

Debris flow，as a common geological disaster，has a complex formation mechanism with numerous influencing factors and multiple uncertainties. To comprehensively consider the synergistic effects of various influencing factors，based on information fusion and uncertainty analysis theory，this paper proposed a debris flow susceptibility evaluation method based on evidence theory and cloud model. Firstly，the BPA function of key evaluation indicators for debris flow susceptibility was calculated using a connection cloud model. Subsequently，the reliability and uncertainty of the indicators' BPA were modified using Lance distance and DENG entropy，respectively，resulting in a corrected BPA. Finally，evidence fusion was performed on the corrected BPA based on Dempster-Shafer (D-S) evidence theory to achieve debris flow susceptibility assessment，followed by a case validation. The results show that the connection cloud model used in this paper overcomes the limitation that the normal cloud model requires indicators to follow the normal distribution when calculating BPA，and it considers the randomness and uncertainty of indicator distribution. The proposed method's evaluation results are generally consistent with those of four other commonly used evidence fusion methods，proving it to be effective and feasible for debris flow susceptibility evaluation. The conflict evidence fusion method improved based on Lance distance and DENG entropy can enhance the convergence speed and precision of evidence fusion，making the results more accurate and reliable.

To protect the occupational health and safety of ¹³¹I nuclear therapy workers and increase the utilization rate of ¹³¹I nuclear therapy，¹³¹I nuclear therapy workplaces in 10 hospitals in Shenzhen were selected in this study. The iodine box filter membrane sampling method，combined with a low background high-purity germanium γ energy spectrometer and passive efficiency calibration software，was used to measure the ¹³¹I activity concentration in critical areas of nuclear medicine workplaces. The accumulated effective dose of occupational personnel was estimated，and then the radiation safety risk of occupational personnel was evaluated. Furthermore，the effect of the correction factor change of ¹³¹I nuclide treatment operation on the radiation safety risk of occupational personnel was analyzed. The results showed that when the correction factor of ¹³¹I (liquid) nuclide treatment operation mode was set to 10，the radiation safety risk was far below the standard limit for manufacturer delivery and automatic packaging in nuclear medicine workplaces. It was recommended that the correction factor of the operation model of ¹³¹I (liquid) radionuclide therapy be distinguished by the packaging system，with manual packaging set to 1 and manufacturer delivery and automatic packaging set to 10.

To solve the current safety risk issues of UAV operations in low-altitude urban environments，a FBN was used to identify and analyze the key risk factors of low-altitude UAV operations. Firstly，risk factors were analyzed from the perspective of human-machine-environment-management based on operation process of low-altitude UAVs. GeNIe software was used to develop a Bayesian network(BN) for risk assessment of low-altitude UAV operations，and the prior probabilities of the underlying events were analyzed using expert prior knowledge and fuzzy sets. Finally，univariate，bivariate，and sensitivity analyses were performed，and the network feasibility was validated. The results indicated that the key risk factors for low-altitude UAV operation were UAV battery failure，environmental obstacles on the operation route，and UAV operation supervision technology. FBN reverse inference showed that environment-related risk (79%) and UAV equipment risk (60%) were the main risk factors in the UAV operation process.

In order to evaluate the development of muscle fatigue during drilling operations in the hand-over-head posture，a simulated drilling test was conducted to measure the maximum voluntary contraction (MVC) of muscles before the test，the maximum residual muscle strength (MRF) after the test，the degree of strength output attenuation (ΔF)，and ratings of perceived exertion (RPE) of wrists，elbows，and shoulders. MET was recorded. By setting different combinations of three operating surfaces (front，side，and bottom) and three operating heights as experimental variables，the effects of different operating methods on muscle fatigue during drilling operations under hand head posture were compared. Subsequently，the effects of three operating surfaces (front，side，and bottom) and three operating heights on MET，MRF，ΔF，as well as RPE of wrist，elbow，and shoulder were analyzed. Research has shown that using frontal manipulation and reducing arm lift height can effectively alleviate muscle fatigue. Different operating surfaces significantly affect MET，MRF，and ΔF，as well as RPE of the wrist，elbow，and shoulder. Different operating heights significantly affect MET，MRF，and RPE of the elbow. MET prediction model established in this article can reflect the muscle fatigue status of personnel during drilling operations in the hand-head posture.

In order to solve the unreasonable problem of coal mine safety investment structure and decision scheme，the safety investment evaluation system was established to comprehensively evaluate the decision scheme of a coal mine over the years. Firstly，based on the perspective of safety value，considering the relationship between safety function and safety output，eight evaluation indexes were selected to construct the safety investment evaluation system of coal enterprises. Secondly，entropy weight method and analytic hierarchy process (AHP) were used to determine the index weight comprehensively. Finally，the SPA-TOPSIS method was used to analyze and evaluate the 2012-2022 decision scheme of a coal mine，and the evaluation scheme was optimized and the improvement suggestions for practical problems were proposed. The results show that the coal mine enterprises should pay more attention to the investment in safety education and industrial health indicators. Coal mine enterprises should comprehensively consider the safety function needs and safety output benefits when making safety investment decisions and reasonably adjust the focus of future safety investment decision by referring to the optimal investment allocation.

In order to understand the research status and development trends of evacuation lighting in disaster scenarios，based on Citespace and literature visualization tools，408 articles as samples up to July 2023 were selected from the core journal database of China National Knowledge Infrastructure (CNKI) and Web of Science (WOS)，and analyzed from the aspects of publication year，journal source，author organization，topic clustering and keywords. Results show that this topic has appeared a rapid upward trend in English literature in the past 10 years. Most of the researchers are from the United States and China. There has been no significant growth in Chinese literature during the same period. The research in China focuses on building fire evacuation，and some nighttime disaster-appropriate lighting. English focuses on a variety of disaster scenarios，which tends to extend from indoor evacuation lighting to outdoor evacuation lighting. The research method is mainly technical application and problem induction in Chinese，and experimental simulation and behavioral research in English. Its research method from real scene simulation to model calculation combined with virtual reality is worthy learning. It is necessary to strengthen research on evacuation lighting in various disaster types and multiple scenarios，and explore evacuation lighting methods suitable for disaster evacuation in outdoor environments in the future.