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Ding H.,Taiyuan University of Technology | Ding H.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Chang Q.,Taiyuan University of Technology | Chang Q.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | And 4 more authors.
Meitan Xuebao/Journal of the China Coal Society | Year: 2016

In order to not excessively rely on domain experts and the inherit experimental knowledge of the experts, this paper presents a prediction model of shearer power based on Extreme Learning Machine (ELM), and combined with the mapping relationship between condition attributes and decision attributes for the overall design technical parameters determination in the design process. The model is built and optimized by identifying the optimum number of neurons on hidden layer with genetic algorithm, determining the excitation function with progressive comparison, randomly generating input weights and hidden elements bias and calculating hidden layer nodes output matrix, hidden layer and output layer connection weights. The model could output the predictive values of shearer power according to different original conditions input by users. Real design data were adopted to do algorithm analysis and contrast experiment with the reasoning model based on Support Vector Machine (SVM). The results show that ELM model can be used to complete a single power prediction in 600 ms. The average relative error of predicted values and real value is within 2.5%. The prediction accuracy of the proposed model is better than that of SVM model and it is of an apparent advantage over SVM model in learning speed. The reasoning efficiency has been improved significantly. ©, 2016, China Coal Society. All right reserved.


Long R.-S.,Taiyuan University of Technology | Long R.-S.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Sun S.-N.,Northeastern University China | Lian Z.-S.,Taiyuan University of Technology | Lian Z.-S.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment
Materials Science and Technology (United Kingdom) | Year: 2016

In order to restrict the generation and propagation of cracks in thin wall metal parts fabricated by laser direct deposition shaping method, using 'element birth and death' technique, a three-dimensional multitrack and multilayer thin wall model was developed, and the deposition process was simulated. Different scanning methods, including long edge parallel reciprocating scanning, short edge parallel reciprocating scanning and interlayer orthogonal parallel reciprocating scanning, were introduced. The effects of different substrate preheating temperatures were also researched. The von Mises equivalent stress and its X-, Y-and Z-directional principal stresses were analysed in detail. Under the same conditions used in the simulations, the deposition experiments were conducted, and the crack generation and restriction mechanism of thin wall metal parts were further discussed. © 2016 Institute of Materials, Minerals and Mining.


Liao Y.,Taiyuan University of Technology | Liao Y.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Yuan H.,Taiyuan University of Technology | Yuan H.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | And 5 more authors.
Strojniski Vestnik/Journal of Mechanical Engineering | Year: 2015

The 1000 L/min large flow hydraulic system for the hydraulic support used in a coal mine is currently a topic of great interest. The large flow directional valve is a key component for hydraulic systems, so the design of the 1000 L/min large flow directional valve is essential. The designed single-channel valve shows serious hysteresis characteristics in a 1000 L/min large flow condition, but it does not happen in a 16 L/min small flow condition. Based on this phenomenon, the computational fluid dynamics (CFD) technology was used to simulate the flow in the valve. It was discovered that the single-channel caused unbalanced pressure in the annular region and on the surface of the valve spool, so the valve spool is subjected to great radial unbalanced force. Then a double-channel valve was designed to improve the pressure distribution. The simulated radial unbalanced force on the double-channel valve is 67.2% lower than that of the single-channel valve. The experimental results showed that the hysteresis characteristics also disappeared under the 1000 L/min large flow condition. Therefore, the conclusion can be drawn that the hysteresis characteristics of the single-channel valve is due to the radial unbalanced force caused by the unsymmetrical flow field. The results show that the maximum radial unbalanced force the valve spool can withstand is 170 N. Furthermore, symmetrical flow passages have to be taken into account in large flow conditions. This paper provides valuable references for the design of large flow valves. © 2015 Journal of Mechanical Engineering. All rights reserved.


Ri-Sheng L.,Taiyuan University of Technology | Ri-Sheng L.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Shao-Ni S.,Northeastern University China | Zi-Sheng L.,Taiyuan University of Technology | Zi-Sheng L.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment
Engineering Failure Analysis | Year: 2016

In order to improve the quality of thin-wall metal parts fabricated by laser direct deposition shaping method, using "element birth and death" technique, a three-dimensional multitrack and multilayer thin-wall model was developed. Different scanning methods, including long-edge parallel reciprocating scanning, short-edge parallel reciprocating scanning and inter-layer orthogonal parallel reciprocating scanning, were researched. The Von Mises equivalent stress, and its X-directional, Y-directional and Z-directional principal stresses were analyzed in detail. Under the same conditions used in the simulations, the deposition experiments were conducted, and the influence of different scanning methods on the cracking failure behavior of thin-wall metal parts was discussed. © 2015 Elsevier Inc.


Liao Y.,Taiyuan University of Technology | Liao Y.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Lian Z.,Taiyuan University of Technology | Lian Z.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | And 4 more authors.
International Journal of Applied Electromagnetics and Mechanics | Year: 2015

The large flow electro-hydraulic directional valves are the key operating components for automation of the hydraulic roof supports in the coal mine. Cracking is a common failure mode of the valve. Effects of the buffer damp diameter, the valve type and the static pressure on the stress of the valve were researched. The valve dynamic behavior was investigated by AMESim. The transient collision stresses of the inlet valve sleeve of the main control valve under different buffer damp diameters and different valve types were investigated by ANSYS/LS-DYNA. The static stress analysis was conducted in ANSYS too. Results show that the valve failure is due to the fatigue of the inlet valve sleeve when suffered from the collision stress wave in the valve opening process, rather than the lack of component strength. The buffer damp diameter, the key parameter of the valve, has a significant effect on the collision stress of the inlet valve sleeve. The integrated type valve has a better stress state compared to the separated type valve. This paper provides an effective method to solve the fracture problems of hydraulic directional valves. It is also significant for the design and optimization of hydraulic components. © 2015 - IOS Press and the authors. All rights reserved.


Long R.,Taiyuan University of Technology | Long R.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Long R.,Shenyang Puyue Group | Sun S.,Northeastern University China | And 5 more authors.
International Journal of Mining Science and Technology | Year: 2015

In order to realize the safety, high efficiency and rapidity of hard rock tunneling, we propose the drilling & hydraulic impact hard-rock tunneling (DHIHT) technology and method. Based on the LS-DYNA explicit module and APDL programming, the key parameters of DHIHT, including drilling spacing and drilling radius, were investigated. The simulation results show that: the drilling spacing should not exceed 0.20 m-larger distances weaken the actual breaking effect; the best drilling radius is about 0.035 m, larger or smaller distances would both decrease the effect of drilling-hole free surfaces. The field impact breaking experiments were conducted in Baitaizi township granite quarry, Jinzhou, Liaoning province, China. The experiment results indicate that DHIHT is a feasible method for hard-rock tunneling, but its efficiency still needs to be further optimized and improved. © 2015 Published by Elsevier B.V. on behalf of China University of Mining & Technology.


Xie J.,Taiyuan University of Technology | Xie J.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Yang Z.,Taiyuan University of Technology | Yang Z.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | And 4 more authors.
Xitong Fangzhen Xuebao / Journal of System Simulation | Year: 2015

For there was no connection among coal mine machinery equipment design, manufacture and its actual work environment, virtual assembly and simulation system, consisting of virtual assembly subsystem, scene simulation and roaming subsystem etc., were realized ultimately, which took shearer, scraper conveyor, roadheader and hoister as the study objects and were supported by double channel prop scene system as the hardware and Visual Studio and Open Scene Graph as the software platform, integrating force feedback, data gloves and other human interface devices, virtual assembly and simulation system made equipment operating status visible in the process of the coal production. In this way, a direct work-filed sense and a new design mode could be provided for the product design. Virtual assembly and simulation system has good immersion and interaction performance, improves products assemblability and its development efficiency and reduces the design cost. ©, 2015, Xitong Fangzhen Xuebao/Journal of System Simulation. All right reserved.


Long R.,Taiyuan University of Technology | Long R.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment | Sun S.,Northeastern University China | Lian Z.,Taiyuan University of Technology | Lian Z.,Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment
Mathematical Problems in Engineering | Year: 2015

In order to realize the rapid hard-rock tunneling in a safe, highly effective, and economic manner, the hydraulic drilling impact hard-rock tunneling (HDIHT) technology and method were introduced based on the theories of rock mechanics and hydraulic impact. The key parameters, including drilling radius and impact distance, were researched to reveal the stress behavior during HDIHT process. The Von Mises equivalent stress and its principal stress components were analyzed, and the breaking mechanism of HDIHT was also discussed. The simulation results show that, to ensure the effectiveness of "secondary breaking" caused by drilling hole free surfaces, the impact distance should not exceed 200 mm, and the optimal drilling radius was about 35 mm. Copyright © 2015 Risheng Long et al.

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