A mechinery fault diagnosis expert system based on case-based reasoning (CBR) technology was established. The process of the CBR fault diagnosis is analyzed from three main aspects: expression and memory, retrieving a...A mechinery fault diagnosis expert system based on case-based reasoning (CBR) technology was established. The process of the CBR fault diagnosis is analyzed from three main aspects: expression and memory, retrieving and matching, and modification and maintenance of a case. The results indicate that the CBR method is flexible and simple to implement, and it has strong self-studying ability. Using a large enough number of case reasoning sets, it can accumulate the experience of problem solving, avoid the difficulty of knowledge acquisition, shorten the course of solving problems, improve efficiency of reasoning, and save the time of developing.展开更多
The noise level of coal face by full-mechanized coal winning technology was measured in a coal mine. And then it was analyzed and evaluated using environment science, ergonomics and fussy mathematics analysis. Basis o...The noise level of coal face by full-mechanized coal winning technology was measured in a coal mine. And then it was analyzed and evaluated using environment science, ergonomics and fussy mathematics analysis. Basis of the statistics and analysis of the measured noise level some measures, such as applying the new materials and improving the construction of the equipment, were carried out. The resuts show that they can reduce the noise level, improve the working environment and enhance the work efficiency.展开更多
The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS ...The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS micro machining sub system. In a first step, the influence of the process parameters on the kerftaper angle of metallic alloys was systematically investigated without beam inclination. A set of base parameters was derived for the subsequent investigations. In a second step, the kerftaper angle was controlled by static beam inclination. In a third step, the same optics was used in its dynamic precession mode to fabricate micro-mechanical components of complex contours with perpendicular 0~ taper angles. It was found that taper angle adjustments of up to 7.5~ are possible with the used setup for cutting applications. Taper angle control is possible both in the static beam inclination mode and in the dynamic precession mode. The static mode could be interesting for contours with sharp inner radii and for achieving faster cutting times similar to results with fixed optics, but would require excellent synchronization of beam inclination and axis motion. The dynamic precession mode would allow an easier integration of the optics into a laser machine but will result in longer cutting times and limitations with respect to achievable inner radii.展开更多
To control movement,the brain has to integrate proprioceptive information from a variety of mechanoreceptors.The role of proprioception in daily activities,exercise,and sports has been extensively investigated,using d...To control movement,the brain has to integrate proprioceptive information from a variety of mechanoreceptors.The role of proprioception in daily activities,exercise,and sports has been extensively investigated,using different techniques,yet the proprioceptive mechanisms underlying human movement control are still unclear.In the current work we have reviewed understanding of proprioception and the three testing methods:threshold to detection of passive motion,joint position reproduction,and active movement extent discrimination,all of which have been used for assessing proprioception.The origin of the methods,the different testing apparatus,and the procedures and protocols used in each approach are compared and discussed.Recommendations are made for choosing an appropriate technique when assessing proprioceptive mechanisms in different contexts.展开更多
基金Funded by Scientific Research Foundation of PLA General Equipment Department (No.20020214).
文摘A mechinery fault diagnosis expert system based on case-based reasoning (CBR) technology was established. The process of the CBR fault diagnosis is analyzed from three main aspects: expression and memory, retrieving and matching, and modification and maintenance of a case. The results indicate that the CBR method is flexible and simple to implement, and it has strong self-studying ability. Using a large enough number of case reasoning sets, it can accumulate the experience of problem solving, avoid the difficulty of knowledge acquisition, shorten the course of solving problems, improve efficiency of reasoning, and save the time of developing.
文摘The noise level of coal face by full-mechanized coal winning technology was measured in a coal mine. And then it was analyzed and evaluated using environment science, ergonomics and fussy mathematics analysis. Basis of the statistics and analysis of the measured noise level some measures, such as applying the new materials and improving the construction of the equipment, were carried out. The resuts show that they can reduce the noise level, improve the working environment and enhance the work efficiency.
文摘The objective of this work was to investigate the possibility of taper angle correction in cutting of complex micro-mechanical contours using a TruMicro ultra-short pulse laser in combination with the SCANLAB precSYS micro machining sub system. In a first step, the influence of the process parameters on the kerftaper angle of metallic alloys was systematically investigated without beam inclination. A set of base parameters was derived for the subsequent investigations. In a second step, the kerftaper angle was controlled by static beam inclination. In a third step, the same optics was used in its dynamic precession mode to fabricate micro-mechanical components of complex contours with perpendicular 0~ taper angles. It was found that taper angle adjustments of up to 7.5~ are possible with the used setup for cutting applications. Taper angle control is possible both in the static beam inclination mode and in the dynamic precession mode. The static mode could be interesting for contours with sharp inner radii and for achieving faster cutting times similar to results with fixed optics, but would require excellent synchronization of beam inclination and axis motion. The dynamic precession mode would allow an easier integration of the optics into a laser machine but will result in longer cutting times and limitations with respect to achievable inner radii.
基金the University of Canberra,Key Laboratory of Exercise and Health Sciences of Ministry of Education,Shanghai University of Sport and Shanghai Municipal Science and Technology Commission (No.13490503800)supported by Shanghai Pujiang Program (No.15PJ1407600)
文摘To control movement,the brain has to integrate proprioceptive information from a variety of mechanoreceptors.The role of proprioception in daily activities,exercise,and sports has been extensively investigated,using different techniques,yet the proprioceptive mechanisms underlying human movement control are still unclear.In the current work we have reviewed understanding of proprioception and the three testing methods:threshold to detection of passive motion,joint position reproduction,and active movement extent discrimination,all of which have been used for assessing proprioception.The origin of the methods,the different testing apparatus,and the procedures and protocols used in each approach are compared and discussed.Recommendations are made for choosing an appropriate technique when assessing proprioceptive mechanisms in different contexts.