Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal re...Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way.展开更多
Within today＇s product development process, various FE-simulations （finite element） for the functional validation of the desired characteristics are made to avoid expensive testing with real components. Those simul...Within today＇s product development process, various FE-simulations （finite element） for the functional validation of the desired characteristics are made to avoid expensive testing with real components. Those simulations are performed with great effort for discretization, use of simulations conditions, like taking different non-linearities （i.e., material behavior, etc.） into account, to create meaningful results. Despite knowing the effects of deformations occurring during the production processes, always the non-deformed design model of a CAD-system （computer aided design） is used for the FE-simulations. It seems rather doubtful that further refinement of simulation methods makes sense, if the real manufactured geometry of the component is not considered for in the simulation. For an efficient exploit of the potential of simulation methods, an approach has been developed which offers a geometry model for simulation based on the existing CAD-model but with integrated production deviations as soon as a first prototype is at hand by adapting the FE-mesh to the real, 3D surface detected geometry.展开更多
In this paper, we study the single neutral top-higgs （h0） production processes at the CERN Large Hadron Collider （LHC） and the International Linear Collider （ILC）. At the LHC, the production rates of processes ...In this paper, we study the single neutral top-higgs （h0） production processes at the CERN Large Hadron Collider （LHC） and the International Linear Collider （ILC）. At the LHC, the production rates of processes pp →Z（W）h0 are too small to detect ht0. However, with the reasonable parameter values, the cross sections can reach the level of 102 fb for qq→qqh0process and 103 fb for top quark associated production process pp → th0 ＋ X, respectively. At the ILC, we study the single top-higgs production processes e-y → veW-h0 and yy → W＋W-h0 in e-y and yy collisions. It is found that the production cross sections can reach the level of a few t-b with reasonable parameter values. Furthermore, such processes with the flavor-changing decay mode h0 tO might provide typical signatures to detected the top-higgs. Therefore, it is hopeful to find the signal of top-higgs at the LHC and ILC experiments via theses processes and test the TC2 model directly.展开更多
文摘Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way.
文摘Within today＇s product development process, various FE-simulations （finite element） for the functional validation of the desired characteristics are made to avoid expensive testing with real components. Those simulations are performed with great effort for discretization, use of simulations conditions, like taking different non-linearities （i.e., material behavior, etc.） into account, to create meaningful results. Despite knowing the effects of deformations occurring during the production processes, always the non-deformed design model of a CAD-system （computer aided design） is used for the FE-simulations. It seems rather doubtful that further refinement of simulation methods makes sense, if the real manufactured geometry of the component is not considered for in the simulation. For an efficient exploit of the potential of simulation methods, an approach has been developed which offers a geometry model for simulation based on the existing CAD-model but with integrated production deviations as soon as a first prototype is at hand by adapting the FE-mesh to the real, 3D surface detected geometry.
基金supported by the National Natural Science Foundation of China (Grant No.11147193)
文摘In this paper, we study the single neutral top-higgs （h0） production processes at the CERN Large Hadron Collider （LHC） and the International Linear Collider （ILC）. At the LHC, the production rates of processes pp →Z（W）h0 are too small to detect ht0. However, with the reasonable parameter values, the cross sections can reach the level of 102 fb for qq→qqh0process and 103 fb for top quark associated production process pp → th0 ＋ X, respectively. At the ILC, we study the single top-higgs production processes e-y → veW-h0 and yy → W＋W-h0 in e-y and yy collisions. It is found that the production cross sections can reach the level of a few t-b with reasonable parameter values. Furthermore, such processes with the flavor-changing decay mode h0 tO might provide typical signatures to detected the top-higgs. Therefore, it is hopeful to find the signal of top-higgs at the LHC and ILC experiments via theses processes and test the TC2 model directly.
