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To meet the need of modernized coal dressing, topology theory was used to build a kind of hybrid mechanism 2PRRR-R which can work as a main excitation mechanism of three freedom degree hybrid vibration screen with two-translation and one-rotation. Next, D′Alembert’s principle was introduced to establish a kinetic model of vibration screen frame and surface, and kinematic equations of directions of vibration screen frame and surface was achieved. Then, ADAMS was used to perform kinetic simulation of vibration screen, and kinetic parameters of the hybrid vibration screen was finally tested on multi-dimensional vibration screening test bench. The research shows that kinetic parameters’ numerical simulation of hybrid vibration screen with two-translation and one-rotation basically agrees with spot test value, which verifies the feasibility of the mechanism design, that the screen frame is of two motion freedom, that screen surface is of three motion freedom degree, that the rotation of the screen surface is relatively independent and controllable. The research provides further study of kinetic properties and development of hybrid vibration screen with two-translation and one-rotation with workable reference.

To analyze liquid metal flow in mold under multidimensional vibration condition, discrete element method (DEM) is taken to approximately stimulate liquid metal flow and to simulate numerically liquid metal flow filling process in casting technique under multidimensional vibration. The orthogonal experiment design is taken to study vibration dimension, frequency as well as amplitude influence on liquid metal filling capacity; Through EDEM platform, numerical simulation research in each test scheme can be carried out to get influence of filling time upon sensitivity degree of each parameter index so as to select the optimal test scheme. Casting experiment results in the self-made solidification test-bed under multidimensional vibration match the numerical simulation, showing that multidimensional vibration could significantly improve filling capacity of castings.

In order to reduce the false alarm rate in coal mine fire warning system, we apply information fusion technology to the system and propose a fire forecast algorithm based on Rough Set Support Vector Machine ( RS-SVM ). Firstly, we map the feature description of coal mine fires to the knowledge representation system described by rough set; Secondly, we discrete the continuous attributes and eliminate the redundant information for attribute reduction to form a rule set of this knowledge representation system; At last, we use the above rule set as the training sample to optimize the parameters for the fire warning support vector machine. The experimental results show that the accuracy of the algorithm is very high. It can make timely and accurate prediction of coal mine fire.

At present, pulley produced in China has been able to meet the demand of domestic and international markets. But there are many problem of the pulley industry in our country, such as too many production enterprises and the low level of export products. And as components of drive system are light weight and raw material price of pulley casting are rising, manufacturing requirements of the pulley are also more and more high. Aiming at the casting defects of pulley that enterprise current product, pulley casting blank model of common material HT250 be made by three-dimension software, numerical simulation of filling and solidification process for pulley sand casting by the casting simulation software Procast, the size and location of the various casting defects were forecasted and analyzed, reflecting the pulley filling and solidification process of the actual situation, due to the thicker pulley rim and less heat dissipation, position of shrinkage is close to the middle of rim [, a method of eliminating defects is proposed to realize sequential solidification, and thus to minimize porosity shrinkage and improve casting performance and reduce casting time and reduce production costs.

Vibration moulding of expendable pattern casting (EPC) was simulated by three dimensional discrete element method, a special EPS tube for test was devised, and the law of vibration form on the motion of sand group was summed up. The results show that vibration form and filling motion of sand group in-tube has consistency in the direction, at the same time gravity and tube direction have a great influence on sand group motion, which leads to particularity of Z tube and Z vibration.

Using three-dimensional discrete element method (DEM) to simulate the vibration of the evaporated pattern casting molding process, accordingly summary the influence law of vibration direction effecting on dry sand filling. The results show that the 3DOF vibration filling effect is best, 2DOF takes second place, 1DOF is the worst. In the 2DOF vibration the YZ direction is best, XY direction worst. Meanwhile Y direction vibration works best in 1DOF vibration, second is X direction, and Z direction gets worst.

The deformation monitoring of surrounding rock and data processing in tunnel is the foundation and safety technical support of underground engineering information control and management. However, due to the special environment in the underground engineering construction, acquiring the deformation information of surrounding rock accurately and fast to assess the stability of surrounding rock is becoming one of the bottleneck problems for underground construction project information to be solved. According to the underground engineering projects, Based on the dynamic monitoring data processing and analysis, a set of underground engineering construction monitoring measurement data processing system is established, which can meet the acquisition of the monitoring measurement data, the arrangement of the measured data, data analysis and feedback, the monitoring data regression analysis.

Joint training model of university-enterprise cooperation is an important platform for realizing the smooth application of a plan for educating and training outstanding engineers (PETOE). This paper analyzes the current situation of PETOE and makes clear principles in the joint training model of university-enterprise cooperation. By discussing construction of simultaneous practice-study theory, training system in practice and perfection of new training mechanism of university-enterprise cooperation, a benign and long-term joint training model of university-enterprise cooperation could be established and quality in training mechanical engineering talents could be improved.

According to the principle of the spring constant support device, a kind of large deformation yielding anchor bolt with three elongation properties has been designed. This paper analyzes the performance of the dynamically-pressured soft rock roadway surrounding rock and support mechanism of yielding anchor, carries out the force analysis of the anchor head, derives equation of the knife-type cam and uses Matlab programming to solve the knife -shaped cam contour curve. In the condition of keeping certain anchoring force, the anchor head can produce large displacement along the anchor body in order to decrease the pressure. And after the pressure of surrounding rock relief, the anchor head can move back to add pressure to form a “Loose - support”cycle of flexible supporting.

In order to reduce casting defects and improve casting quality, the author has developed a three-dimensional parallel vibration casting machine based on parallel mechanism. The paper introduces the three-dimensional parallel vibration casting machine in structure composition and functional properties, the casting machine degree of freedom of excitation mechanism is calculated, its motion performance is analyzed, and the kinematics equations are established. The designed casting machine achieves support and excitation functional separation of moving parts which takes complete decoupling of hybrid mechanism 2PRRR-P (2R ) as excitation mechanism, realizing flask vibration along the X, Y, Z three directions. Test results show that, the casting machine can significantly improve casting quality, raise labor productivity, save casting raw materials, and reduce the production costs.

Basing on the basic principle of the mechanical movement, the movement and dynamic performance analysis of Opposed Reciprocating Ten-Plunger Pump are done. The equations about position, velocity and acceleration of the 10 plungers are deduced. The motion characteristics of each plunger are calculated. Thus, the calculation model of the equivalent resistance torque of the-plunger is simplified. The drag torques on the crankshaft is gotten. So the equivalent torque and equivalent power on the crankshaft are analyzed. At the same time, the efficiency of the selected motor is analyzed in order to achieve good power save control.