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Double inner and outer latticed shell string structure is a new type of space structure. The new structural system is to reduce the space occupied by roof structure and could be laid by the rigid roofing material conveniently. Based on the local analysis method and the whole system balance, a numerical algorithm was introduced and some suggestions for improvement were put forward. An example was investigated and the results confirmed the feasibility of the proposed method.

There isn`t clear definition of steep inclined coal seam at home or abroad at present. Generally,the inclined coal seam with 35°~55° inclination is called steep inclined coal seam in mining field [. During the mine program in steep inclined coal seam,due to its special formation of roof and floor,not only perpendicular pressure to coal seam is distinct,but also the component of gravity along the direction parallel to coal seam is significantly increased and the parallel pressure which causes slippage of roof and floor is the main factor resulting in the distinct roadway transformation. Uncertainty and asymmetry transformation or destroy of roadways brings great difficulties to the mine of steep inclined coal seam,especially for the asymmetry transformation which is a huge challenge to the support of roadways,so it`s necessary to summary and analyse the factors affecting asymmetry transformation of roadways in steep inclined coal seal. Through classifying these factors by the main and secondary,this paper will provide reference for reasonable arrangement of roadways and effective support scheme in steep inclined coal seam. Many scholars did some research in laws of roadway deformation in steep inclined coal seam,but few of them compared or did sensitivity analyse of these factors. Zhang Bei etc. built the numerical simulation models of roadways with different inclination and found the key position of the deformed surrounding rocks [;Sun Xiaoming etc. aimed at the asymmetric deformation of surrounding rock around deep roadways and investigated its failure mechanism and coupling control countermeasure [;Cao Shugang etc. analysed the stress distribution rules of roadways in steep inclined and medium coal seam by ADINA program and put forward some control measures [. In different inclination conditions, this paper simulates asymmetry deformation of roadways with different section form in steep inclined coal seam through FLAC3D program and analyses the sensitivity of these factors affecting asymmetric deformation.

In the biological aerated filter, the number of microorganisms and activity play a key role on the removal of the organic matter. Studying the microbial mass distribution is a useful method for understanding the organic matter degradation mechanism, and it can provide theoretical basis for the operations. Blood count plate was adopted to determine the number of living bacterium, the test results show that attachment biomass of activated carbon reduce with the increase of the height. The biomass and the viable bacterial number counted in the height of 25cm from BAF water level is 15.0 CFU/g·dwC whereas 3.24mg/g·dwc by VAS, which is the largest along the height. Backwashing restored the microbial activity in BAF, after back washing, biomass at different height from25 to105cm are 0.6 mg VAS/g·dwc or so, which is almost similar to filtering beginning.

This Research was based on domestic and international pressure leak calibration technology, respectively, constant volume method and constant pressure(two model: saw-tooth variation constant pressure measurement mode and digital PID measurement mode) were both used on identical pressure leak calibration, 10-6 Pa•m3/s level, then, measurement uncertainty analysis of each method and the calibration results were compared.

On laboratory conditions，background leakage caused by temperature change was one of the most important factors for affecting calibration of pressure leak, consequently, the constant temperature water bath of the calibration apparatus has been used to reduce background leakage by means of keeping the apparatus temperature constant. The method of active and passiveness were combined to keep constant temperature. through the research on experimentation, it was found that background leakage was decreased to the grade of 1.36×10-9Pam3/s when constant temperature been used, and meanwhile the lower limiting of pressure leak was extended to 2.667×10-8Pam3/s.

This paper based on an equipment which measure the outgassing of vacuum material,adopt some method, constant volume, otiose flux and double channels and so on, testing the deflation of stainless steel(316、304)brass H62, aluminium2A12, and other representative material deflation.We adopt light eradiate to heat up, and the temperature control range is 23°C~300°C, we study the rule of outgassing rate at different temperature, and use QSM to analyze the component of gas.

Ergonomics and interior geometry are important validation contents in vehicle product development. In this paper, a fully adjustable physical mockup with the flexibility to install various interiors was developed, which can be used to validate the ergonomics and interiors for any target population and various passenger cars. By requirements analysis, target vehicle types and contents needed to be validated using this equipment were identified. Based on statistical analysis of the sizes of different passenger cars, the dimensions of basic structure and the adjustments ranges of main components were determined, as well as the main functions and structural requirements. Based on above analysis, reference fiducial marks system, and the positions and travels of adjustment devices were calculated. According to the validated concept design, considering the standards of section bars and machines, the main structure and adjustment devices of every component were designed and analyzed of their strength, stiffness and kinematics. Together with the manufacturer, the sub-systems of the mockup were produced, assembled and tested. The acceptance test showed that this mockup could simulate and present different passenger cars well as the design target, and could evaluate, modify and reevaluate various ergonomic problems and interior designs.

The irregular face mechanized mining is one of the difficult problems in the field of mining engineering. In this thesis, the roadways of 4324 extremely irregular face in DaiZhuang Mine were taken as research object. Through on-site mine pressure observation, the deformation characteristics of the surrounding rock and support force was analyzed. Next the mine pressure appeared rule of the roadways was study. This study benefited that the production of 4324 mining face went on wheels, at the same time, it had important significance to production safety of irregular working face with similar conditions.

It is mining subsidence that causes the damage of ecological environment and the surface buildings. The basic method to relieve the damage is to controll surface subsidence effetely. For this problem, the thesis studied the characteristics of overlying rock failure through theoretical analysis, on the basis of the mechanism of surface subsidence. Then we obtained three main factors to subsidence which are sunken, compression, and lithological characters. According to the main factors influencing mining subsidence under cut and fill mining, then we reduce the impact from these factors successfully by taking appropriate measures to control it.

A measurement apparatus for vacuum material outgassing rates was developed, which was mainly composed of four systems, including pumping system, switching between two pumping paths(SPP) measurement system, constant volume measurement system, bake heating and light irradiation heating system. The ultimate pressure, 10-9Pa, was thus obtained in the UHV chamber by combining the magnetically levitated turbo pump with mechanical pump. The test principles of constant volume method and SPP method were described, and several vacuum material outgassing rates such as copper were tested at room temperature. The lower measurement limiting value of apparatus can be extended to 10-12 Pam3s-1cm-2.

A jaw mechanism based on the biomechanical findings of human mastication system is being developed to simulate jaw motion and investigate its effect on jaw function to provide the basis for jaw model. Following an investigation into the biological process of mastication, a linear cylindrical actuator is used to replace a group of muscles, and it can act bio-directionally with both origin and insertion attached to the skull and the mandible via spherical joints. The trajectory of the incisal point can be reproduced through programming the six actuations. So it builds the functional `relation between incisal point and six actuators. Co-simulations for motion and control have been conducted using the ADMAS and SIMULINK and the results have indicated that the jaw mechanism enables the jaw behaviors to be reproduced perfectly.