In this paper, a composite grid method (CGM) for finite element (FE) analysisof an electromagnetic field with strong local interest is proposed. The method is based on theregular finite element method in conjunction w...In this paper, a composite grid method (CGM) for finite element (FE) analysisof an electromagnetic field with strong local interest is proposed. The method is based on theregular finite element method in conjunction with three basic steps, i.e. global analysis, localanalysis, and modified global analysis. In the first two steps, a coarse finite element mesh is usedto analyze the global model to obtain the nodal potentials which are subsequently used asartificial boundary conditions for local regions of interest. These local regions with theprescribed boundary conditions are then analyzed with refined meshes to obtain more accuratepotential and density distribution In the third step, a modified global analysis is performed toobtain more improved solution for potential and density distribution. And iteratively, successivelyimproved solutions can be obtained until the desired accuracy is achieved. Various numericalexperiments show that CCM yields accurate solutions with significant savings in computing timecompared with the regular finite element method.展开更多
In this paper,a two-scale finite element approach is proposed and analyzed for approximationsof Green's function in three-dimensions.This approach is based on a two-scale finite elementspace defined,respectively,o...In this paper,a two-scale finite element approach is proposed and analyzed for approximationsof Green's function in three-dimensions.This approach is based on a two-scale finite elementspace defined,respectively,on the whole domain with size H and on some subdomain containing singularpoints with size h (h << H).It is shown that this two-scale discretization approach is very efficient.In particular,the two-scale discretization approach is applied to solve Poisson-Boltzmann equationssuccessfully.展开更多
In this paper, potential energy curves for the X1∑＋, a3П, a＇∑＋, da△, A1П and I∑- states of CO have been calculated using complete active space se1f-consistent field and multi-reference configuration interacti...In this paper, potential energy curves for the X1∑＋, a3П, a＇∑＋, da△, A1П and I∑- states of CO have been calculated using complete active space se1f-consistent field and multi-reference configuration interaction methods. The calculations have been performed at 108 nuclear separations from 0.7 to 4.0 A by the aug-cc-PVSZ basis set. Spectroscopic constants for the six low-lying electronic states are found in good agreement with experimental data. The vibrational states of the X1∑＋ and A1П states are also calculated, which are reliable and accurate by comparison with the experimental data and the other theoretical values. The transition dipole moment （TDM） shows that the TDM of the two states （X1∑＋→A1П）are reduced strongly with increase of bond length.展开更多
文摘In this paper, a composite grid method (CGM) for finite element (FE) analysisof an electromagnetic field with strong local interest is proposed. The method is based on theregular finite element method in conjunction with three basic steps, i.e. global analysis, localanalysis, and modified global analysis. In the first two steps, a coarse finite element mesh is usedto analyze the global model to obtain the nodal potentials which are subsequently used asartificial boundary conditions for local regions of interest. These local regions with theprescribed boundary conditions are then analyzed with refined meshes to obtain more accuratepotential and density distribution In the third step, a modified global analysis is performed toobtain more improved solution for potential and density distribution. And iteratively, successivelyimproved solutions can be obtained until the desired accuracy is achieved. Various numericalexperiments show that CCM yields accurate solutions with significant savings in computing timecompared with the regular finite element method.
基金partially supported by the National Science Foundation of China under Grant Nos. 10425105 and 10871198the National Basic Research Program under Grant No. 2005CB321704
文摘In this paper,a two-scale finite element approach is proposed and analyzed for approximationsof Green's function in three-dimensions.This approach is based on a two-scale finite elementspace defined,respectively,on the whole domain with size H and on some subdomain containing singularpoints with size h (h << H).It is shown that this two-scale discretization approach is very efficient.In particular,the two-scale discretization approach is applied to solve Poisson-Boltzmann equationssuccessfully.
基金Project Supported by the Fundamental Research Funds for the Central Universities and the National Natural Science Foundation of China under Grant No. 61102024
文摘In this paper, potential energy curves for the X1∑＋, a3П, a＇∑＋, da△, A1П and I∑- states of CO have been calculated using complete active space se1f-consistent field and multi-reference configuration interaction methods. The calculations have been performed at 108 nuclear separations from 0.7 to 4.0 A by the aug-cc-PVSZ basis set. Spectroscopic constants for the six low-lying electronic states are found in good agreement with experimental data. The vibrational states of the X1∑＋ and A1П states are also calculated, which are reliable and accurate by comparison with the experimental data and the other theoretical values. The transition dipole moment （TDM） shows that the TDM of the two states （X1∑＋→A1П）are reduced strongly with increase of bond length.
