This paper presents finite element formulas based on two Surface elastoplastic yielding model. The study also discusses the numerical procedures and develops the corresponding software. These formulas have provided ac...This paper presents finite element formulas based on two Surface elastoplastic yielding model. The study also discusses the numerical procedures and develops the corresponding software. These formulas have provided accurate elastoplastic method for analysing concrete, rock and soil like materials.展开更多
为解决冷轧带钢板形和轧机动作的模型驱动与人机交互问题,以冷轧带钢出口张应力横向分布和板带屈曲判别模型为基础,提出了基于VRML高程格网(Elevation Grid)节点的虚拟带钢建模技术,实现了边浪、中浪等常见板形缺陷的量化解析预测和三...为解决冷轧带钢板形和轧机动作的模型驱动与人机交互问题,以冷轧带钢出口张应力横向分布和板带屈曲判别模型为基础,提出了基于VRML高程格网(Elevation Grid)节点的虚拟带钢建模技术,实现了边浪、中浪等常见板形缺陷的量化解析预测和三维动态可视化呈现,并结合国内某厂2 230 mm冷连轧机组出口板形仪实测数据,将浪形几何参数数值预测结果与现场带钢板形缺陷进行对比,两者吻合良好。在此基础上,以650 mm UCM单机架可逆冷轧机组为对象,利用MATLAB/Simulink 3D Animation工具箱,将轧机、带钢、厂房车间等VRML三维场景与轧制过程Simulink仿真模型进行了通讯集成,为虚拟现实系统开发奠定了基础。展开更多
Objective： To create a 3-dimensional finite element model of knee ligaments and to analyse the stress changes of lateral collateral ligament （LCL） with or without displaced movements at different knee flexion condi...Objective： To create a 3-dimensional finite element model of knee ligaments and to analyse the stress changes of lateral collateral ligament （LCL） with or without displaced movements at different knee flexion conditions. Methods： A four-major-ligament contained knee specimen from an adult died of skull injury was prepared for CT scanning with the detectable ligament insertion footprints, locations and orientations precisely marked in advance. The CT scanning images were converted to a 3-dimensional model of the knee with the 3-dimensional reconstruction technique and transformed into finite element model by the software of ANSYS. The model was validated using experimental and numerical results obtained by other scientists. The natural stress changes of LCL at five different knee flexion angles （0°, 30°60°, 90°, 120°） and under various motions of anterior-posterior tibial translation, tibial varus rotation and internal-external tibial rotation were measured. Results： The maximum stress reached to 87%-113% versus natural stress in varus motion at early 30° of knee flexions. The stress values were smaller than the peak value of natural stress at 0° （knee full extension） when knee bending was over 60° of flexion in anterior-posterior tibial translation and internal-external rotation. Conclusion： LCL is vulnerable to varus motion in almost all knee bending positions and susceptible to ante- rior-posterior tibial translation or internal-external rotation at early 30° of knee flexions.展开更多
文摘This paper presents finite element formulas based on two Surface elastoplastic yielding model. The study also discusses the numerical procedures and develops the corresponding software. These formulas have provided accurate elastoplastic method for analysing concrete, rock and soil like materials.
文摘为解决冷轧带钢板形和轧机动作的模型驱动与人机交互问题,以冷轧带钢出口张应力横向分布和板带屈曲判别模型为基础,提出了基于VRML高程格网(Elevation Grid)节点的虚拟带钢建模技术,实现了边浪、中浪等常见板形缺陷的量化解析预测和三维动态可视化呈现,并结合国内某厂2 230 mm冷连轧机组出口板形仪实测数据,将浪形几何参数数值预测结果与现场带钢板形缺陷进行对比,两者吻合良好。在此基础上,以650 mm UCM单机架可逆冷轧机组为对象,利用MATLAB/Simulink 3D Animation工具箱,将轧机、带钢、厂房车间等VRML三维场景与轧制过程Simulink仿真模型进行了通讯集成,为虚拟现实系统开发奠定了基础。
文摘Objective： To create a 3-dimensional finite element model of knee ligaments and to analyse the stress changes of lateral collateral ligament （LCL） with or without displaced movements at different knee flexion conditions. Methods： A four-major-ligament contained knee specimen from an adult died of skull injury was prepared for CT scanning with the detectable ligament insertion footprints, locations and orientations precisely marked in advance. The CT scanning images were converted to a 3-dimensional model of the knee with the 3-dimensional reconstruction technique and transformed into finite element model by the software of ANSYS. The model was validated using experimental and numerical results obtained by other scientists. The natural stress changes of LCL at five different knee flexion angles （0°, 30°60°, 90°, 120°） and under various motions of anterior-posterior tibial translation, tibial varus rotation and internal-external tibial rotation were measured. Results： The maximum stress reached to 87%-113% versus natural stress in varus motion at early 30° of knee flexions. The stress values were smaller than the peak value of natural stress at 0° （knee full extension） when knee bending was over 60° of flexion in anterior-posterior tibial translation and internal-external rotation. Conclusion： LCL is vulnerable to varus motion in almost all knee bending positions and susceptible to ante- rior-posterior tibial translation or internal-external rotation at early 30° of knee flexions.
