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The assessment of airfield runway destruction effectiveness and functional recovery time is of great importance in the field of operational assessment. In this paper, the criteria and methods of damage assessment of airfield runways are studied in the context of the sub-bomb against airfield runways and the benefits of striking airfield runways as a starting point. Firstly, the main purpose of attacking airport runway is blockade, and the damage assessment criteria of runway should focus on its time benefit. Then, it is concluded that calculating the minimum lifting window can only achieve the purpose of blockade of airport, and the optimal lifting window is needed to calculate the airport function recovery time. A direction search algorithm is proposed to search the optimal lifting window on the airport runway after striking, and an example is given.

To explore the influence of interlocking depth and block number on the compressive performance of interlocking block masonry, seven kinds of interlocking depth and three kinds of block number are selected, and ABAQUS software is used to carry out numerical simulation analysis. The results show that when the interlocking depth is 10 mm, the compressive performance of masonry is better. With the increase in the number of blocks, the compressive strength of masonry decreases gradually. Based on the numerical simulation results, a recommended formula for the average compressive strength of interlocking block masonry is proposed.

Based on ELAN multimodal discourse analysis software, this paper constructs a multimodal Russian translation model based on the machine translation model with visual grammar and multimodal discourse analysis as the theoretical basis. To address the issue of missing semantics caused by insufficient input information at the source of real-time translation, the model uses images as auxiliary modalities. The real-time Russian translation model is constructed using the wait-k strategy and the concept of multimodal self-attention. Experiments and analysis are carried out on the Multi30k training set, and the generalization ability and translation effect of the model are finally evaluated with the test set. The results show that by applying multimodal discourse analysis to Russian translation, the three translation evaluation indexes of BLEU, METEOR, and TER are improved by 1.3, 1.0, and 1.4 percentage points, respectively, and the phenomenon of phantom translation is effectively reduced.

With stringent vehicle emissions regulations, high efficiency and cleanliness have become the development target of engine combustion and fuel technology. The gasoline additives could enhance fuel performance and thus contribute to engine combustion efficiency improvement and emissions control. In this study, the influences of gasoline detergent, friction modifier, and combustion improver on engine combustion and emissions are reviewed. Literature studies have shown that the gasoline detergent reduces carbon monoxide (CO), hydrocarbons (HC), and particulate matter (PM) emissions, and improves fuel economy by removing engine deposits and inhibiting their formation. There is an optimal concentration of gasoline detergent, which means that gasoline detergent with too low or too high concentration cannot effectively remove engine deposits. Combustion improvers contribute to faster and more complete fuel combustion, resulting in reduced pollutant emissions and increased engine power output. With the addition of friction modifiers, a liquid film is formed between the piston and the cylinder, which reduces friction losses between the engine moving parts, resulting in a small improvement in engine fuel economy.

Liquid CO2 fracturing in low-permeability coal seams has dual gas-enhanced drainage effects of fracture reconstruction and displacement. It is a permeability enhancement technology that is easy to be used in combination with other technologies and has the potential for large-scale application. This paper proposes a theoretical system and a complete set of technical framework for fracturing and permeability enhancement of low-permeability coal seam with liquid CO2; according to the principle of stress superposition and the maximum tensile stress criterion, a model for determining the initiation pressure of liquid CO2 fracturing was established considering the change of phase state and low viscosity and strong permeability of liquid CO2 during the injection process; taking type I fracture criterion as the discriminant condition of fracture propagation, the quantitative characterizing relationship between fracturing orifice pressure and fracture propagation distance under constant fluid injection flow was established, and the influence law of fluid injection pressure, fracturing fluid viscosity and fracture occurrence on fracture propagation was clarified. On this basis, the four key parameters and their calculation methods to determine the performance of the complete set of equipment for liquid CO2 fracturing and permeability improvement in coal seam were proposed, the first complete set of equipment for underground fracturing and permeability improvement in China was developed, and the construction technology of fracturing and permeability improvement was developed, which was applied in Huainan Mining Area and Binchang Mining Area respectively.

In order to effectively prevent and control coal spontaneous combustion disasters in Tangjiahui Mine, thermogravimetric experiments were used to analyze the thermal reaction kinetics characteristics of coal samples at different heating rates and different oxygen volume fractions. The results showed that at the same oxygen volume fraction, the apparent activation energies of coal at heating rates of 2 ℃/min, 5 ℃/min, 10 ℃/min were 150.27 kJ/mol, 131.97 kJ/mol, 106.86 kJ/mol, respectively; in addition, at the same heating rate, the apparent activation energies of coals with oxygen volume fraction of 6%, 9%, 12%, 15%, 18%, 21% are 106.86, 120.61, 127.31, 131.58, 135.26 and 136.82 kJ/mol, respectively. The apparent activation energies decrease with the increase of heating rate and oxygen volume fraction, and the change law is basically in line with the increase of logarithmic function. The calculation results of activation energy kinetics reveal that the degree of coal-oxygen composite reaction is different under different heating rates and different oxygen volume fractions.

Cadmium sulfide quantum dots (CdS QDs) are being developed for sensors, fluorescent probes, and other platforms and are attracting increasing attention. Given the growing demand for QDs, it is clear that there is a need to understand their potential toxicity to organisms. However, little is known regarding the genotoxicity of CdS QDs to humans. Therefore, this study used CdS QDs as the research object, cultured human peripheral blood lymphocytes, and randomly divided them into a control group, CdS I group (CdS QDs), and CdS II group (CdS QDs coated with thioglycolic acid). After cultivation, we measured the olive tail distance, tail length, tail DNA%, lymphocyte micronucleus rate, and aneuploid rate. The comet test results indicated that the indices of the QD group were significantly larger than those of the control group (P < 0.05). The results of the micronucleus and chromosome aberration tests showed that the lymphocyte micronucleus rate and chromosome aneuploid rate in the QD group were significantly increased (P < 0.05) compared with those in the control group. In conclusion, CdS QDs have certain genotoxicity to human peripheral blood lymphocytes, and the DNA damage caused by CdS QDs encapsulated with thioglycolic acid is less severe than that caused by nonencapsulated CdS QDs.

Aiming at the problems and technical difficulties in the vertical rescue process of mines, such as single information collection and low degree of visualization, a set of technology methods such as multi-media collection, fusion of multiple information, wired and wireless transmission, and intrinsically safe control of communication circuits have been developed. The life information detection system of the long distance borehole has been successfully applied in the collapse accident of Wanzhuang gypsum mine in Pingyi County, Linyi City, Shandong Province and the explosion accident of Hushan gold mine in Qixia City, Shandong Province. Field rescue application results show that: the life information detector has strong reliability, stable information transmission, with video/audio and underground environmental parameters collection and synchronous transmission functions, real-time feedback of detected multimedia information to the ground rescue command, and the information is automatically saved to the terminal equipment to provide reference materials for formulating scientific rescue plans and subsequent accident summary.

In order to solve the problems of low transmission efficiency, high carbon emissions, environmental pollution, low intelligence, and poor flexibility in traditional fuel-driven and front-wheel steering high ground clearance sprayers, a new type of high ground clearance four-wheel independent drive (4WID) sprayer which was suitable for the unmanned driving was proposed in this research. The sprayer adopted the hybrid power of fuel and battery and was steered by the 4WID driving mode of the front and rear double steering axles. For this reason, the turning radius of the proposed 4WID sprayer was small, and the running track of the front and rear wheels were uniform in height, which reduced the phenomenon of seedling crushing during field plant protection operations. Considering the slippage and sinking of the driving wheel in the extremely complex operating environment of the paddy field, based on the linear time-varying kinematics model (LTV) of the sprayer, a layered path tracking control considering the slippage of the driving wheel was constructed. The upper model predictive controller (MPC) obtained the steering angle and movement speed of the sprayer according to the expected path and the current position of the vehicle to realize path tracking. The lower layer used fuzzy control and integral separation PID control to construct a driving wheel slip controller, so as to achieve effective control of path tracking, speed, and driving wheel slip, which improved the stability and path tracking accuracy of the sprayer in a complex operating environment. The co-simulation results of Adams and Matlab showed that under complex working conditions, the slip rate of the driving wheel of the sprayer was controlled within ±20%, so as to prevent excessive slip of the driving wheel from having adverse effects on the speed and steering angle, which was conducive to the improvement of the stability of the sprayer. The sprayer could be tracked quickly and accurately the desired path, the path tracking in road conditions outside attached coefficients were 0.3 and 0.7 of the lateral deviation could be controlled within ±0.018 m. In stage C roughness 3D road conditions, the sprayer could adjust the steering angle of the front wheels in time to stabilize the body posture and the lateral deviation could be controlled within ±0.054 m. Compared with the controller that didn't consider the slip of the driving wheel, the stability and path tracking accuracy of the sprayer had been significantly improved.

Most of the existing research on the influencing factors of coal electrical parameters are carried out under fixed frequency or low frequency and high temperature conditions. There is a lack of research on the influencing factors of coal electrical parameters under ultra-wideband frequency and normal temperature conditions. Therefore, there are certain limitations in the research on the influencing factors of coal electrical parameters. To address this problem, in order to study the influence of coal electrical parameters on the selection of ultra-wideband radar wave mine detection frequency band under different conditions, the Concept-80 ultra-wideband dielectric spectrum test system is applied. The system is set to detect the relative permittivity, electrical conductivity and loss angle tangent values of coals with different metamorphic degrees (lignite, long-flame coal and lean coal) at 0-80 ℃ and 500-1 000 MHz detection frequency and analyze their variation laws. The analysis results show that the relative permittivity of coal increases with the increase of coal metamorphic degrees, and the electrical conductivity and loss angle tangent values of coals decrease with the increase of coal metamorphic degrees. The relative permittivity of coal samples with different metamorphic degrees decreases, then increases and decreases again with the increase of detection frequency, and the relative permittivity is positively correlated with temperature. The electrical conductivity is positively correlated with both detection frequency and temperature. The loss angle tangent value is positively correlated with temperature. However, the detection frequency does not reflect the variation of loss angle tangent value well. Based on the variation law of three electrical parameters at different temperatures and detection frequencies, and the comprehensive comparison of influence of three electrical parameters on the transmission of ultra-wideband radar waves in coal, it is pointed out that the frequency of 550-650 MHz performs best when using 500-1 000 MHz ultra-wideband radar waves to penetrate the coal body for detection at 0-80 ℃, and the detection frequency should decrease as the temperature increases. The conclusion of this study can provide a reference for the selection of ultra-wideband radar wave mine detection frequency band under different conditions.

The research status of the key technologies of multi-rotor detection unmanned aerial vehicles(UAVs) in mine dangerous areas at home and abroad is reviewed from three aspects: autonomous positioning and navigation technology, autonomous obstacle avoidance technology and multi-sensor information fusion technology. Autonomous positioning and navigation technology enables robots to move autonomously in unknown environments without human intervention. Combined navigation technology, 3D environment map building technology, deeply optimized trajectory planning algorithms and simultaneous positioning and map building technology based on semantic and deep learning are suitable for mine conditions with complex and unstable mine environmental conditions where disaster information evolving over time.The obstacle avoidance method based on multi-sensor information fusion can ensure that the multi-rotor detection UAV can perceive obstacle information to the maximum extent under different environmental conditions. The sensor fusion architecture based on autonomous positioning and obstacle avoidance technology need to adopt a distributed structure to make the mine multi-rotor detection UAV system have high reliability and fault tolerance.The problems of multi-rotor detection UVAs are analyzed from both software and hardware aspects. The problems include that the universality of the fusion model and algorithm cannot be guaranteed,the fusion system's fault tolerance or robustness needs to be improved, the lack of processing hardware to adapt to a variety of complex fusion algorithms, and the low degree of integration, high power consumption and large size of multi-sensor.The development trend of key technologies of multi-rotor detection UAVs in mine dangerous areas is prospected. ① Fusion algorithm optimization: it is crucial to maximize the optimization of fusion algorithm, improve system reliability and stability and ensure stable and efficient data processing. ② Application of artificial intelligence technology: improving the deep learning ability of multi-rotor detection UAVs and expanding the detection range of mine dangerous areas by applying intelligent technologies such as machine learning and adaptive technology. ③ Development of processing hardware that can adapt to multiple complex fusion algorithms: the conditions of mine dangerous area are extremely complex, and it is difficult to achieve simultaneous collection and processing of underground multi-source information without the processing hardware that can adapt to the deep fusion of multiple algorithms. Therefore, the information processing ability of multi-rotor detection UAVs can be improved by developing processing hardware with strong adaptability. ④ Development of convenient hardware fusion system: developing a fusion system based on the deep integration of multiple sensors could further enhance the detection capabilities of multi-rotor detection UAVs.

This paper analyzes the elements and chemical components contained in the gasification ash through elemental analysis and X-ray fluorescence spectroscopy, and proposes that the gasification ash should be poured into underground goaf as grouting fire prevention material. In order to solve the problem that the gasification ash slurry is easy to block the pipeline during the long-distance transportation process, the polymer surfactant carboxymethyl cellulose（ＣＭＣ） is used as the suspending agent. Water separation rate and fluidity of the slurry are tested by suspension and flow experiments under different water-cement ratios and suspending agent additions. The results show that the gasification ash contains a variety of metal elements and non-metal elements. These elements mainly exist in the form of oxides. The oxides with higher content are SiO2, Fe2O3, CaO and Al2O3. When the amount of gasification ash and CMC increased, the water extraction rate and fluidity of grout decreased gradually. Through the suspension test, when the slurry water-cement ratio is 1∶0.2, the CMC addition amount should be greater than 1.25%. When the water-cement ratio is 1∶0.4, 1∶0.6 or 1∶0.8, the CMC addition amount should be greater than 0.5%. If the water-cement ratio is 1∶1, the addition amount of CMC should be greater than 0.25%. If the water-cement ratio exceeds 1∶1, the slurry appears as paste, which does not meet the requirements of grouting.

By analyzing research status of power system, positioning system, environmental monitoring system and communication system of mine detection unmanned aerial vehicle (UAV) at home and abroad, the problems of mine detection UAV were pointed out, such as insufficient cruising power, poor positioning accuracy, weak information perception ability and poor information data transmission performance. For the above problems, the development trends of mine detection UAV were prospected: ① Application of new energy or new power supply technology, the whole power management system is optimized in a more efficient and reasonable way to detect power consumption of electric equipment in real time, improve power efficiency and enhance endurance time of detection UAV, and meet explosion-proof performance. ② Development of UAV cluster system based on collaborative navigation search, the hybrid UAV cluster control structure overcomes the shortcomings of poor communication reliability and low search efficiency in distributed structure and solves the problems of weak robustness and autonomy in centralized structure; the system can improve the positioning accuracy and shorten the rescue time through mathematical optimization algorithm for information derivation and multi-UAV collaborative information fusion. ③ Design of UAV monitoring platform based on multi-sensor fusion technology, the multi-sensor information coordination and mutual fusion based on BP neural network algorithm can improve the UAV's perception ability to underground environment. ④ Application of multi-UAV chain wireless Mesh networking mode, when multi-UAVs search in underground environment, the information collected by each UAV is local area information， all UAVs conduct information fusion and resource complementarity to update the environmental information status in real time through the chain wireless Mesh networking mode, so as to improve reliability of detection and rescue efficiency.

The research status of intelligent monitoring and early warning technology in coal mine in China was summarized from the aspects of Internet of things, big data, cloud computing and artificial intelligence.According to practical application of intelligent monitoring technology in coal mine, the problems of intelligent monitoring and early warning in coal mine was points out, including poor reliability of precursory information collection of underground coal mine monitoring equipment, insufficient depth of cloud platform integrated application and fusion, weak database security, and immature application of artificial intelligence technology in coal mine monitoring.The development trend of intelligent monitoring and early warning technology in coal mine was prospected: the application of graphene/graphene oxide optical fiber sensors in intelligent monitoring system of coal mine can realize multi-source information perception and improve the reliability of precursory information collection; studying multi-technology deep cross fusion to explore deep value of monitoring data; constructing coal mine monitoring database based on block chain technology, ensuring that the database cannot be tampered and has good read and write performance; developing intelligent safety monitoring and warning system with adaptive and deep learning, realizing mine automatic monitoring and intelligent early warning.

An optimization design and application of high temperature–resistant shielding material was carried out according to the nuclear power plant source characteristics and special protection requirements such as loss-of-coolant accident (LOCA). The composition of lead–boron polyethylene shielding composite was optimized based on the genetic algorithm and Monte Carlo methods and then realized by blending modification and graft copolymerization to improve its high temperature–resistant, shielding, and mechanical properties. Then comprehensive properties such as mechanical, neutron shielding, damp heat aging, irradiation resistance, and high temperature resistance were tested. These experiments proved that the high temperature–resistant lead–boron polyethylene shielding composite has excellent performance; especially, as it is able to keep a complete structure in a high-temperature environment of up to 190°C for 48 h. Finally, the shielding composite was applied to the shielding door design of a reactor pit chamber. When the shield thickness is 60 mm, the level of the neutron dose rate was reduced by 10 times, and that of the γ dose rate was reduced by 5 times, which meets all the requirements of radiation protection safety for nuclear power plants.

The paper introduced general situation of explosion-proof technology of coal mine rescue robot, and summarized the research status and application of explosion-proof technology of coal mine rescue robot at home and abroad, and pointed out some progress of explosion-proof technology for coal mine rescue robot, especially in explosion-proof motor, explosion-proof shell and power supply. However, there are still problems in explosion-proof material application technology, energy power technology, intrinsic safety control technology, fault diagnosis and fault-tolerant control technology, it needs to be constantly improved in the aspects of processing materials lightweight, power supply efficiency, intrinsic safety of explosion protection technology, intelligent control system, so as to ensure the explosion-proof technology of each component of coal mine rescue robot is more mature.

The research status and application of power system, explosion-proof design, multi-parameter monitoring and communication system of coal mine rescue robots at home and abroad were introduced, and the existing problems of coal mine rescue robots, such as limited cruising ability, short walking control distance, heavy weight of explosion-proof materials, poor reliability of information processing and transmission were pointed out. The development trend of coal mine rescue robots was prospected, that is, research and development of new energy batteries suitable for coal mine is one of the development trends of power supply of coal mine rescue robot, research and development of intelligent robots with autonomous walking, positioning and path planning is the development trend of coal mine rescue robots in the future, lightweight explosion-proof materials, intelligent integration of multi-source information, wireless and wired communication mode will also be the direction of intelligent development of coal mine rescue robots.

A new rolling shear mechanism which is driven by one horizontally positioned hydraulic cylinder is put forward through analyzing the present shear mechanism at home and abroad. In order to achieve pure rolling and shearing,the simplify model of PR-11RⅢ-level composite rod linkage mechanism is obtained.Besides,by using the method of assur-group decomposition modeling,the dynamics model of every assur-group and corresponding simulation model are established,and the simulation module of the corresponding function is compiled. Finally,depending on the development project on extensive popularization of 2 000 mm rolling shear mechanism driven by one hydraulic cylinder of a machinery company,the dynamics simulation is conducted by using the Matlab/Simulink. The important basis for mechanism design of the rolling shear and control principle analysis and actual use is provided by the dynamics curve and parameter of key hinge joint botained from the simulation result,the correctness of the dynamic analysis is verified.