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The status of anti-aircraft weapon system firing precision test is introduced firstly, and aiming at the deficiencies of high cost and long cycle and complicated organization process, a virtual and actual complex firing test method based on sampling is proposed and the principle of virtual and actual complex firing test is introduced. Then the structure chart of virtual and actual complex firing test system is put forward, and system’s major functions are mainly discussed in this paper. The data flow, organizing execution flow and validation notion of virtual and actual complex firing test are acquired finally.

Numerical simulation method and on-site dynamic monitoring are used to study a railway laneway disturbed by excavation of neighboring roadways under high in-situ stress in a deep coal mine of Huainan region. The paper presents a series of variation trend about stress state, deformation, plastic zone and tension of cables under disturbance effects based on the simulation results, and the evolution of surface displacement of railway laneway is also discussed according to on-site monitoring data. The analysis shows that disturbance effects have spatiotemporal characteristics and support structure should be installed in a short time which helps to reduce disturbance by construction of adjacent caverns.

Novel BCN nanotubes (BCN NTs) for NOx gas sensor have been synthesized by the CVD method at room temperature. The BCN NTs have been investigated with XPS and TEM. The diameter of the BCN NTs is in the range of 20-50 nm and the tubes exhibit bamboolike structure. By using NOx as a probe molecule, the BCN NTs exhibit excellent sensing performance in terms of high response, fast response and good stability at room temperature. The outstanding performance in gas sensing of BCN NTs owes to their one-dimensional nanostructures, more defects and active sites doping carbon nanotubes with B, N. The possible gas sensing mechanism of the BCN NTs is explained by a model in which the effect of NOx adsorption on BCN nanotubes and the electronic transport properties increase after doping carbon nanotubes with B, N.

To explore the relationship among the erosion ability of high-pressure cavitating water jets, hydraulic parameters and rock nature with a series of experiments relating to the efficiency of rock-breaking with cavitating water jets for different porosity of rock under different confining pressures and pump pressures. The results show that the erosion efficiency (erosion mass and erosion depth) of cavitating water jets is fitted a conic curve with pump pressure and confining pressure. It increases with the pump pressure increases while decreases with the confining pressure increases; the length of the bubble cloud decreases with the confining pressure increase and the length increases with the pump pressure increase, which is accorded with cubic curve. The bubble cloud length influences the rock-breaking efficiency by deciding the valid stand-off distance directly. Under the experimental condition, the cavitation happens once the pump pressure reaches 7MPa, and the cavitating water jets can crushing the sandstones which the uniaxial compressive strength is 96MPa. On the other hand, the porosity of rock is another main factor of rock breakage with high pressure cavitating water jets. The higher the porosity of rock is, the easier the rock can be broken.