Due to the complexity of investigating deformation mechanisms in helical rolling(HR) process with traditional analytical method, it is significant to develop a 3D finite element(FE) model of HR process. The key formin...Due to the complexity of investigating deformation mechanisms in helical rolling(HR) process with traditional analytical method, it is significant to develop a 3D finite element(FE) model of HR process. The key forming conditions of cold HR of bearing steel-balls were detailedly described. Then, by taking steel-ball rolling elements of the B7008 C angular contact ball bearing as an example, a completed 3D elastic-plastic FE model of cold HR forming process was established under SIMUFACT software environment. Furthermore, the deformation characteristics in HR process were discovered, including the forming process, evolution and distribution laws of strain, stress and damage based on Lemaitre relative damage model. The results reveal that the central loosening and cavity defects in HR process may have a combined effect of large negative hydrostatic pressure(positive mean stress)caused by multi-dimensional tensile stresses, high level transverse tensile stress, and circular-alternating shear stress in cross section.展开更多
In this paper, we analyzed the status of human resource management practices in western China state-owned and state holding enterprises azld private enterprises, and found that there are differences in the nature of t...In this paper, we analyzed the status of human resource management practices in western China state-owned and state holding enterprises azld private enterprises, and found that there are differences in the nature of the business combination of different patterns of human resource management practices.展开更多
Performance management has become a competitive advantage of enterprises to cultivate core competitiveness of strategic initiatives, but how to act performance management out scientifically has been difficult. An uncl...Performance management has become a competitive advantage of enterprises to cultivate core competitiveness of strategic initiatives, but how to act performance management out scientifically has been difficult. An unclear understanding of the various issues often results in improper handling counterproductive. Thus, we should analyze human resource performance management problems and their causes, and only on this basis can we establish and implement effective hunlan resource management system dynamic performance during the difficulties and the main factors that should be considered to elaborate.展开更多
基金Project(2011CB706605)supported by the National Basic Research Program of ChinaProject(IRT13087)supported by the Innovative Research Team Development Program of Ministry of Education of ChinaProject(2012-86)supported by the Grant from the High-end Talent Leading Program of Hubei Province,China
文摘Due to the complexity of investigating deformation mechanisms in helical rolling(HR) process with traditional analytical method, it is significant to develop a 3D finite element(FE) model of HR process. The key forming conditions of cold HR of bearing steel-balls were detailedly described. Then, by taking steel-ball rolling elements of the B7008 C angular contact ball bearing as an example, a completed 3D elastic-plastic FE model of cold HR forming process was established under SIMUFACT software environment. Furthermore, the deformation characteristics in HR process were discovered, including the forming process, evolution and distribution laws of strain, stress and damage based on Lemaitre relative damage model. The results reveal that the central loosening and cavity defects in HR process may have a combined effect of large negative hydrostatic pressure(positive mean stress)caused by multi-dimensional tensile stresses, high level transverse tensile stress, and circular-alternating shear stress in cross section.
文摘In this paper, we analyzed the status of human resource management practices in western China state-owned and state holding enterprises azld private enterprises, and found that there are differences in the nature of the business combination of different patterns of human resource management practices.
文摘Performance management has become a competitive advantage of enterprises to cultivate core competitiveness of strategic initiatives, but how to act performance management out scientifically has been difficult. An unclear understanding of the various issues often results in improper handling counterproductive. Thus, we should analyze human resource performance management problems and their causes, and only on this basis can we establish and implement effective hunlan resource management system dynamic performance during the difficulties and the main factors that should be considered to elaborate.
