The interfacial properties of steel-mushy Al-28Pb bonding plate with different interfacial structures, and the influence of ratio of Fe-Al compound at the interface on interfacial shear strength were investigated. The...The interfacial properties of steel-mushy Al-28Pb bonding plate with different interfacial structures, and the influence of ratio of Fe-Al compound at the interface on interfacial shear strength were investigated. The results show that there is a nonlinear relationship between the ratio of Fe-Al compound at the interface and the interfacial shear strength. When the ratio of Fe-Al compound at the interface is smaller than 71.4%, with the increase of the ratio of Fe-Al compound at the interface, the interfacial shear strength increases gradually; when the ratio of Fe-Al compound at the interface is larger than 71.4%, with the increase of the ratio of Fe-Al compound at the interface, the interfacial shear strength decreases continuously; when the ratio of Fe-Al compound at the interface is 71.4%, the largest interfacial shear strength 70.2MPa is obtained.展开更多
In most studies of tunnel boring machine(TBM)tunnelling, the groundwater pressure was not considered, or was simplified and exerted on the boundary of lining structure. Meanwhile, the leakage, which mainly occurs in t...In most studies of tunnel boring machine(TBM)tunnelling, the groundwater pressure was not considered, or was simplified and exerted on the boundary of lining structure. Meanwhile, the leakage, which mainly occurs in the segment joints, was often ignored in the relevant studies of TBM tunnelling. Additionally, the geological models in these studies were simplified to different extents, and mostly were simplified as homogenous bodies. Considering the deficiencies above, a 3D refined model of the surrounding rock of a tunnel is firstly established using NURBS-TIN-BRe P hybrid data structure in this paper. Then the seepage field of the surrounding rock considering the leakage in the segment joints is simulated. Finally, the stability of TBM water diversion tunnel is studied coupled with the seepage simulation, to analyze the stress-strain conditions, the axial force and the bending moment of tunnel segment considering the leakage in the segment joints. The results illustrate that the maximum radial displacement, the minimum principal stress, the maximum principal stress and the axial force of segment lining considering the seepage effect are all larger than those disregarding the seepage effect.展开更多
In order to meet the polishing requirement of faucets and other products,a novel multi-station rotary polishing robot is designed,which is a PPPR + RR type of degree of freedom( DOF) distribution structure,and is simi...In order to meet the polishing requirement of faucets and other products,a novel multi-station rotary polishing robot is designed,which is a PPPR + RR type of degree of freedom( DOF) distribution structure,and is similar to dual-arm robot. Forward and inverse kinematic analysis is carried out by robot modeling. In order to make this robot structure more compact,first of all,X,Y and Z three moving degrees of freedom( DOF) limit stroke polishing need is calculated by using an artificial fish swarm algorithm,which analyzes dexterous workspace of this robot. Then,on the basis of the above analysis,the three DOF stroke is optimized. Simulation and polishing experimental results verify that this polishing robot with optimized stroke parameters can meet the polishing needs of faucets and other bathroom pieces.展开更多
Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is empl...Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is employed to measure depth. For the special reflection areas,in which the structured light stripe can not be detected directly, the shape of the structured light stripe can be calculated from the corresponding contour. By fusing the information of structured light and the contours, the problem of reflectance influence is solved, and the whole shape of head,including hair area, can be obtained. Some good results are obtained.展开更多
文摘The interfacial properties of steel-mushy Al-28Pb bonding plate with different interfacial structures, and the influence of ratio of Fe-Al compound at the interface on interfacial shear strength were investigated. The results show that there is a nonlinear relationship between the ratio of Fe-Al compound at the interface and the interfacial shear strength. When the ratio of Fe-Al compound at the interface is smaller than 71.4%, with the increase of the ratio of Fe-Al compound at the interface, the interfacial shear strength increases gradually; when the ratio of Fe-Al compound at the interface is larger than 71.4%, with the increase of the ratio of Fe-Al compound at the interface, the interfacial shear strength decreases continuously; when the ratio of Fe-Al compound at the interface is 71.4%, the largest interfacial shear strength 70.2MPa is obtained.
基金Supported by the Foundation for Innovation Research Groups of the National Natural Science Foundation of China(No.51321065)Tianjin Research Program of Application Foundation and Advanced Technology(No.12JCZDJC29200)Tianjin Natural Science Foundation(No.13JCYBJC19500)
文摘In most studies of tunnel boring machine(TBM)tunnelling, the groundwater pressure was not considered, or was simplified and exerted on the boundary of lining structure. Meanwhile, the leakage, which mainly occurs in the segment joints, was often ignored in the relevant studies of TBM tunnelling. Additionally, the geological models in these studies were simplified to different extents, and mostly were simplified as homogenous bodies. Considering the deficiencies above, a 3D refined model of the surrounding rock of a tunnel is firstly established using NURBS-TIN-BRe P hybrid data structure in this paper. Then the seepage field of the surrounding rock considering the leakage in the segment joints is simulated. Finally, the stability of TBM water diversion tunnel is studied coupled with the seepage simulation, to analyze the stress-strain conditions, the axial force and the bending moment of tunnel segment considering the leakage in the segment joints. The results illustrate that the maximum radial displacement, the minimum principal stress, the maximum principal stress and the axial force of segment lining considering the seepage effect are all larger than those disregarding the seepage effect.
基金Supported by the Key Research and Development Project of Yangzhou--Industry Preview and Key Projects(No.YZ2015011)
文摘In order to meet the polishing requirement of faucets and other products,a novel multi-station rotary polishing robot is designed,which is a PPPR + RR type of degree of freedom( DOF) distribution structure,and is similar to dual-arm robot. Forward and inverse kinematic analysis is carried out by robot modeling. In order to make this robot structure more compact,first of all,X,Y and Z three moving degrees of freedom( DOF) limit stroke polishing need is calculated by using an artificial fish swarm algorithm,which analyzes dexterous workspace of this robot. Then,on the basis of the above analysis,the three DOF stroke is optimized. Simulation and polishing experimental results verify that this polishing robot with optimized stroke parameters can meet the polishing needs of faucets and other bathroom pieces.
基金Supported by the National Natural Science Foundation of China(69775022) and 863 Programme of China(863-306-ZT04-06-3)
文摘Three dimensional digitization of human head is desired in many applications. In this paper, an information fusion based scheme is presented to obtain 3-D information of human head. Structured light technology is employed to measure depth. For the special reflection areas,in which the structured light stripe can not be detected directly, the shape of the structured light stripe can be calculated from the corresponding contour. By fusing the information of structured light and the contours, the problem of reflectance influence is solved, and the whole shape of head,including hair area, can be obtained. Some good results are obtained.
