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In the mining process of a coal seam containing a fault structure, due to the influence of mining stress, the rock mass inside the fault zone and between the fault and the coal pillar that is preserved to prevent fault activation is prone to producing damage and activation. This study is focused on this problem. Based on the analysis of the failure, activation and movement of the rock mass in front of the fault body and the coal wall, extended finite element numerical simulation software is adopted to study the stress evolution and deformation failure rules of a coal seam containing a fault floor. In particular, the dynamic response process (including slip velocity, slip distance and friction force) of the fault structure under mining conditions is monitored, and then the turning and failure process of the fault structure is analysed. However, an analogue modelling is reformed. A similar material analysis model is established to monitor the displacement field changes near the fault during the mining process, obtain the movement rules of the fault zone and surrounding rock mass during the mining process, and then verify the reliability of the numerical simulation results. The research results can provide references for exploring the coupling movement rules between the fault and the work area for production in the mining process of coal seam stopes, as well as prevention before water inrush under the influence of the fault and treatment after water inrush.

Based on laboratory experiments, the paper researches the effect of polyvinyl alcohol (PVA) content on the performance of fly ash-based cement grouting materials. The test results show that the addition of PVA has limited effect on the initial and final setting time and brings a certain but minor delay on the appearance of the hydration peak period. It enhances cement hydration during the hydration slow down period. The impermeability of PVA to the grouting material is obviously improved, and it increases with the growing amount of PVA content. PVA improves the flexural strength and compressive strength of the sample block to varying degrees, and the improvement on flexural strength is more obvious than that on the compressive strength. It has a significant effect on the mechanical properties of the grouting material and can effectively improve the rock mass’s hydraulic coupling characteristics. It also has great application value and practical significance for the prevention and control of water hazards in deep coal stopes.

By constructing a coupling analysis numerical model of a Darcy-Forchheimer flow in aquifers, fault zones, and fracture zones after fault water inrush, the variations in porosity, permeability, and volumetric strain under fluid-solid coupling during coal seam mining were studied. The mechanism of fault water inrush was obtained. Grouting was carried out on the aquifer, fault fracture zone, and fracture zone. The mechanisms of flow velocity and pressure evolution in the cross-section during the grouting sealing process were obtained. The simulation results show that the Forchheimer equation can help to effectively simulate and calculate the flow process of current with high water pressure and high flow velocity. There were notable changes in the water pressure partition and porosity after the fault stretch, and the influence of stress-seepage coupling on the non-Darcy flow characteristics in the fault was significant. Through a simulation analysis of grouting at different grouting positions, the change law of flow velocity and pressure in the grouting process was obtained, which is of great significance for selecting appropriate grouting positions and optimizing grouting technology.

This article expounds the working principle and the merits of performance of the library computer room intelligent high heat transfer heat exchanger, analyses the running effects of the heat exchanger in place of the air-conditioner of the library computer room, Analysis showed that the use of the heat exchanger can reduce the working hours of the original air conditioner, extend its life, reduce the cost of operation and maintenance of air-conditioner and the Investment costs of library. The results of energy consumption analysis showed that the energy-saving effect of using the heat exchanger in the library computer room is prominent, and the energy-saving technologies should be promoted.

Vibration fatigue failure is a critical problem of hydraulic pipes under severe working conditions. Strain modal testing of small and light pipes is a good option for dynamic characteristic evaluation, structural health monitoring and damage identification. Unique features such as small size, light weight, and high multiplexing capability enable Fibre Bragg Grating (FBG) sensors to measure structural dynamic responses where sensor size and placement are critical. In this paper, experimental strain modal analysis of pipes using distributed FBG sensors ispresented. Strain modal analysis and parameter identification methods are introduced. Experimental strain modal testing and finite element analysis for a cantilever pipe have been carried out. The analysis results indicate that the natural frequencies and strain mode shapes of the tested pipe acquired by FBG sensors are in good agreement with the results obtained by a reference accelerometer and simulation outputs. The strain modal parameters of a hydraulic pipe were obtained by the proposed strain modal testing method. FBG sensors have been shown to be useful in the experimental strain modal analysis of small and light pipes in mechanical, aeronautic and aerospace applications.

Although MSComm control is widely used on upper machine in the network communication systems, it still has inadequacies, such as inconvenient to operate, not high in safety factor, poor sharing etc. This paper introduced the design and implement of Serial Port Class in a network upper machine system S under Ajax, proposed improvements of applications for MSComm control, constructed a shared example of the Serial Port Class, achieved to share port, and gain, analysis, store the data real time, and effectively solve the inadequacies of MSComm controls.

A new technology that mine goaf is filled with bags of municipal solid waste was proposed according to the method and status of treating municipal solid waste at home and abroad, and more and more severe mining surface subsidence at present. Compared with other treatment technologies of municipal solid waste such as landfill, composting and incineration, this new technology could not only restraint surface subsidence effectively, but also realize harmless and comprehensive treatment of municipal solid waste. So it is very significant to study this technology in science with wide prospect of application.

This article analyzes E-Learning teaching design’s basic instruction, design principle and design core based on the acknowledge of E-Learning teaching design’s concept and connotation, constructing a model of E-Learning teaching system, which takes web curriculum instruction system as an example and guided by Constructivism. And it points out interactive E-Learning web curriculum system usually contains three main functional modules: teacher module, student module and management module. Finally it puts forward specific functional model.

A fiber Bragg grating (FBG) tension sensor for anchor rope has been proposed and implemented in the full-scale impact test of rockfall protection barriers in this paper. According to the measurement principle of the tension sensor, the wavelength shift difference of the two FBGs which, respectively, measure the positive and negative strain in the spring element is utilized as sensing signal. Therefore, the force sensitivity is increased and the temperature cross-sensitivity is compensated. Experimental results indicate that the measurement sensitivity is 14.85 pm/kN in a range from 0 to 150 kN. The dynamic forces on anchor ropes in barriers have been clearly recorded by the designed sensors during the impact test, and the variation of the impact forces could be mainly divided into three stages. This kind of tension sensor is expected to be widely used for force's quasi-distributed measurement or remote monitoring in industrial and mechanical fields.