This paper proposes a digital image processing-based detection algorithm for cross joint traces of coal roadway heading face.Initially,the acquired images were preprocessed,i.e.,adaptive correction was conducted for n...This paper proposes a digital image processing-based detection algorithm for cross joint traces of coal roadway heading face.Initially,the acquired images were preprocessed,i.e.,adaptive correction was conducted for non-uniform illumination images based on the 2D gamma function.The edge detection algorithm was then applied to extract the edges of the structural plane,followed by the filtration of the non-structural plane noises.Moreover,the Hough transform algorithm was applied to extract the linear edges;finally,the edges were locally connected in accordance with the angle and distance criteria.The experimental results show that this algorithm can be used to reduce the noise caused by non-uniform illumination and avoid the mutual interference of multi-scale edges,so as to effectively extract the traces of the cross joint.Furthermore,Q-system and rock mass rating(RMR),were applied to conduct a quantitative evaluation on the stand-up time of unsupported roof in the four test images.The Q-system quality scores are 26.7,43.3,3.1,and 6.7,and the RMR quality scores are 56.84,58.73,48.42,and 51.42,respectively.The stand-up time of unsupported roofs with a span of 4.6 m are 30,36,7.7 and 14 d,respectively.展开更多
The 3D FEM numerical simulation on multi-action precision cold forging technology of universal joint cross and differential spider is done in this article using DEFORM Software, a commercial computer aided engineering...The 3D FEM numerical simulation on multi-action precision cold forging technology of universal joint cross and differential spider is done in this article using DEFORM Software, a commercial computer aided engineering software specializing in forming and heat treatment simulation technology, and suitable for cold, warm and hot forging process. The material flow properties, the dynamic variation of stress and strain in the process of deformation and the load-stroke curve have also been achieved. A good consistency is exhibited between simulation results and practical data. Based on the DEFORM simulation results, the optimized procedure has been found for forging a universal joint cross. What should be emphasized here is that a better understanding of practical forging characters and the environmental factors can greatly improve the simulation accuracy thus make the simulation results more reliable.展开更多
The paper uses the theory of core competence based on knowledge capital to build up international joint venture’s effective capability system of cross-culture. It involves in forming common mind of business, strategi...The paper uses the theory of core competence based on knowledge capital to build up international joint venture’s effective capability system of cross-culture. It involves in forming common mind of business, strategies of glocalization, complementary skills of cross-culture and cross-cultural training. It also presents the case of Lansheng Daewoo Corp to give a positive analysis.展开更多
The study object is the angular output velocity of the drive shaft which is made up of two series-wound cross universal joints. We have deduced the function relation between the angular output velocity and initiative ...The study object is the angular output velocity of the drive shaft which is made up of two series-wound cross universal joints. We have deduced the function relation between the angular output velocity and initiative input angle of the drive shaft with double cross universal joints that is based on the calculation formula of the angular output velocity of a single cross universal joint, and by analyzing the relation between the two input angles. By using this function relation, the constant velocity condition of the drive shaft with double cross universal joints＂ is verified. The step-by-step searching algorithm is adopted to obtain the optimal phase angle that leads to the minimum fluctuate index of the angular output velocity in the vary velocity condition. At the same time, we worked out the maximal and minimum value of the angular output velocity, and their initiative input angle. The correctness of the function of the angular output velocity and the step-by-step search algorithm are verified by an ADAMS simulation example.展开更多
The cross-gradients joint inversion technique has been applied to multiple geophysical data with a significant improvement on compatibility, but its numerical implementation for practical use is rarely discussed in th...The cross-gradients joint inversion technique has been applied to multiple geophysical data with a significant improvement on compatibility, but its numerical implementation for practical use is rarely discussed in the literature. We present a MATLAB-based three-dimensional cross-gradients joint inversion program with application to gravity and magnetic data. The input and output information was examined with care to create a rational, independent design of a graphical user interface (GUI) and computing kernel. For 3D visualization and data file operations, UBC-GIF tools are invoked using a series of I/O functions. Some key issues regarding the iterative joint inversion algorithm are also discussed: for instance, the forward difference of cross gradients, and matrix pseudo inverse computation. A synthetic example is employed to illustrate the whole process. Joint and separate inversions can be performed flexibly by switching the inversion mode. The resulting density model and susceptibility model demonstrate the correctness of the proposed program.展开更多
瞄准制衡强敌“马赛克战”“决策中心战”等新技术驱动的作战概念及威胁挑战,聚焦未来跨域联合作战指挥控制(command and control,C2)全流程决策需求,遵循平行智能理论框架,提出了基于筹划-准备-执行-评估(planning-readiness-execution...瞄准制衡强敌“马赛克战”“决策中心战”等新技术驱动的作战概念及威胁挑战,聚焦未来跨域联合作战指挥控制(command and control,C2)全流程决策需求,遵循平行智能理论框架,提出了基于筹划-准备-执行-评估(planning-readiness-execution-assessment,PREA)环与观察-判断-决策-行动(observe-orient-decide-act,OODA)环的平行指挥控制与管理(command&control and management,C2M)新范式,以期实现智能机器辅助指挥员作战全流程的分层次、个性化决策支持,减轻指挥员认知负担、降低决策复杂度,实现机器对指挥员“人脑”的智能扩展与增强,为塑造全局决策优势提供牵引和支撑。展开更多
基金supported by the National Natural Scieince Foundation of China(Nos.52004204 and 52034007).
文摘This paper proposes a digital image processing-based detection algorithm for cross joint traces of coal roadway heading face.Initially,the acquired images were preprocessed,i.e.,adaptive correction was conducted for non-uniform illumination images based on the 2D gamma function.The edge detection algorithm was then applied to extract the edges of the structural plane,followed by the filtration of the non-structural plane noises.Moreover,the Hough transform algorithm was applied to extract the linear edges;finally,the edges were locally connected in accordance with the angle and distance criteria.The experimental results show that this algorithm can be used to reduce the noise caused by non-uniform illumination and avoid the mutual interference of multi-scale edges,so as to effectively extract the traces of the cross joint.Furthermore,Q-system and rock mass rating(RMR),were applied to conduct a quantitative evaluation on the stand-up time of unsupported roof in the four test images.The Q-system quality scores are 26.7,43.3,3.1,and 6.7,and the RMR quality scores are 56.84,58.73,48.42,and 51.42,respectively.The stand-up time of unsupported roofs with a span of 4.6 m are 30,36,7.7 and 14 d,respectively.
文摘The 3D FEM numerical simulation on multi-action precision cold forging technology of universal joint cross and differential spider is done in this article using DEFORM Software, a commercial computer aided engineering software specializing in forming and heat treatment simulation technology, and suitable for cold, warm and hot forging process. The material flow properties, the dynamic variation of stress and strain in the process of deformation and the load-stroke curve have also been achieved. A good consistency is exhibited between simulation results and practical data. Based on the DEFORM simulation results, the optimized procedure has been found for forging a universal joint cross. What should be emphasized here is that a better understanding of practical forging characters and the environmental factors can greatly improve the simulation accuracy thus make the simulation results more reliable.
文摘The paper uses the theory of core competence based on knowledge capital to build up international joint venture’s effective capability system of cross-culture. It involves in forming common mind of business, strategies of glocalization, complementary skills of cross-culture and cross-cultural training. It also presents the case of Lansheng Daewoo Corp to give a positive analysis.
文摘The study object is the angular output velocity of the drive shaft which is made up of two series-wound cross universal joints. We have deduced the function relation between the angular output velocity and initiative input angle of the drive shaft with double cross universal joints that is based on the calculation formula of the angular output velocity of a single cross universal joint, and by analyzing the relation between the two input angles. By using this function relation, the constant velocity condition of the drive shaft with double cross universal joints＂ is verified. The step-by-step searching algorithm is adopted to obtain the optimal phase angle that leads to the minimum fluctuate index of the angular output velocity in the vary velocity condition. At the same time, we worked out the maximal and minimum value of the angular output velocity, and their initiative input angle. The correctness of the function of the angular output velocity and the step-by-step search algorithm are verified by an ADAMS simulation example.
文摘The cross-gradients joint inversion technique has been applied to multiple geophysical data with a significant improvement on compatibility, but its numerical implementation for practical use is rarely discussed in the literature. We present a MATLAB-based three-dimensional cross-gradients joint inversion program with application to gravity and magnetic data. The input and output information was examined with care to create a rational, independent design of a graphical user interface (GUI) and computing kernel. For 3D visualization and data file operations, UBC-GIF tools are invoked using a series of I/O functions. Some key issues regarding the iterative joint inversion algorithm are also discussed: for instance, the forward difference of cross gradients, and matrix pseudo inverse computation. A synthetic example is employed to illustrate the whole process. Joint and separate inversions can be performed flexibly by switching the inversion mode. The resulting density model and susceptibility model demonstrate the correctness of the proposed program.
文摘瞄准制衡强敌“马赛克战”“决策中心战”等新技术驱动的作战概念及威胁挑战,聚焦未来跨域联合作战指挥控制(command and control,C2)全流程决策需求,遵循平行智能理论框架,提出了基于筹划-准备-执行-评估(planning-readiness-execution-assessment,PREA)环与观察-判断-决策-行动(observe-orient-decide-act,OODA)环的平行指挥控制与管理(command&control and management,C2M)新范式,以期实现智能机器辅助指挥员作战全流程的分层次、个性化决策支持,减轻指挥员认知负担、降低决策复杂度,实现机器对指挥员“人脑”的智能扩展与增强,为塑造全局决策优势提供牵引和支撑。
