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According to the characteristics of the island workface with hard roof, various mechanical models of hard roof in island workface are established, to analyze energy characteristics of hard roof before and after the first fracture in island workface with all round gobs, derived their simplified formulas of bending strain energy for hard roof before and after the first fracture, and using these formulas to estimate the bending strain energy for the typical case of coal bump, reveals the energy cause of coal bump and verify the validity of these formulas.

Slice mining, when mining lower slice need to consider on the effect of current face from top slice, especially when on top slice mining space irregular, it will make mining more difficult. Hair is drainage of these characteristics the lao keng kou mine by Geophysical means, take advantage of the characteristics of the water content in the mined-out area and media mutation specific master distribution of the residual top delamination, geophysical no damage proved an effective means of underground space structure and highly targeted research stoping methods, based on the conclusions formulated to ensure the safety and production measures in place to provide the necessary reference.

At present, the studies of bubble crystallization focus on the gas velocity, crystallization efficiency and crystallization yield, the effects of other factors were not considered. So it is very important to study factors comprehensively that effect on the gas-liquid two-phase flow of bubble crystallization. In this paper, Fluent was used as a computing platform and RNG k-ε turbulence model and VOF multi-phase model was selected to simulate gas-liquid two-phase flow of bubble crystallization. The results show that as the gas inlet velocity increases, slug bubbles are more and more bigger, more and more dispersed bubbles are below the slug bubbles, crystallization efficiency first increases and then decreases; Under the gas pulse-inlet form condition, the better operating parameters are: gas velocity 1.0m/s, pulse duration 0.4s, interval time 0.8s, crystallization tube diameter 40mm. Simulations agree well with experimental data.

A new algorithm for tracking a maneuvering target in presence of clutter or false measurements is addressed. Due to the availability of feature or attribute information in measurement vector, a joint probability density function description of the target state and target class is given. Using the joint state-class description the predictive measurement pdf can be proven to be a Gaussian mixture distribution. A Gaussian mixture Kalman filter is used for state estimation, where maneuver detection can also be avoided. In simulation the results with three tracking algorithms are compared, which have shown that proposed method here is more effective.

With more and more applications of advanced manufacturing mode in enterprise, computer aided parameter design will become increasingly important. In the paper, automatic liquid packaging machine architecture is analyzed, and then shaping principle of lapel shaper is discussed in detail, and key parameter of collar intersecting curve is determined by lapel shaper plane outspread drawing. More ever, solution steps of collar intersecting curve is put forward in detail, and lapel shaper of parametric design base on Visual Lisp is also illustrated by listing general realization flow chart and key code..

An amphiphilic graft copolymer with poly(acrylamide-methacrylate) as a main chain and octylphenyl polyoxyethylene as side chains (P(AM-MA)-g-C8PhEO10) was successfully synthesized via free radical copolymerization. The structure and the composition of the graft copolymer were characterized by FTIR, 1H-NMR and elemental analysis (EA) in detail. The absolute molecular weight of the copolymer is 1.304×106, as determined by static light scattering (SLS). The molar ratio of acrylamide monomer to the macromonomer is 33:1 in the copolymer and 53 C8PhEO10 branch chains attach to a P(AM-MA) backbone. The micellar behavior of P(AM-MA)-g-C8PhEO10 was preliminarily studied by means of surface tension measurements, transmission electron microscope (TEM) in aqueous solution. It was found that the stable spherical micelles with core-shell structure are formed and polymolecular micelles are larger and more compact than monomolecular micelles. In addition, the graft copolymer has favorable thermal stability.