For non-asymmetrical bending problems of elastic annular plates, the exact solutions are not fond. To bending problems of infinite annular plate with two different boundary conditions, based on the boundary integral f...For non-asymmetrical bending problems of elastic annular plates, the exact solutions are not fond. To bending problems of infinite annular plate with two different boundary conditions, based on the boundary integral formula,the natural boundary integral equation for the boundary value problems of the biharmonic equation and the condition of bending moment in infinity,bending solutions under non-symmetrical loads are gained by the Fourier series and convolution formulae. The formula for the solutions has nicer convergence velocity and high computational accuracy, and the calculating process is simpler. Solutions of the given examples are compared with the finite element method. The textual solutions of moments near the loads are better than the finite element method to the fact that near the concentrative loads the inners forces trend to infinite.展开更多
Based on the Kirchhoff transformation and the natural boundary element method, we investigate a coupled natural boundary element method and finite element method for quasi-linear problems in a bounded or unbounded dom...Based on the Kirchhoff transformation and the natural boundary element method, we investigate a coupled natural boundary element method and finite element method for quasi-linear problems in a bounded or unbounded domain with a concave angle. By the principle of the natural boundary reduction, we obtain natural integral equation on circular arc artificial boundaries, and get the coupled variational problem and its numerical method. Moreover, the convergence of approximate solutions and error estimates are obtained. Finally, some numerical examples are presented to show the feasibility of our method. Our work can be viewed as an extension of the existing work of H.D. Han et al..展开更多
Subthreshold conduction is governed by the potential distribution. We focus on full two-dimensional（2D） analytical modeling in order to evaluate the 2D potential profile within the active area of Fin FET structure.S...Subthreshold conduction is governed by the potential distribution. We focus on full two-dimensional（2D） analytical modeling in order to evaluate the 2D potential profile within the active area of Fin FET structure.Surfaces and interfaces, which are key nanowire elements, are carefully studied. Different structures have different boundary conditions, and therefore different effects on the potential distributions. A range of models in Fin FET are reviewed in this paper. Parabolic approximation and evanescent mode are two different basic math methods to simplify the Poisson＇s equation. Both superposition method and parabolic approximation are widely used in heavily doped devices. It is helpful to learn performances of MOSFETs with different structures. These two methods achieved improvement to face different structures from heavily doped devices or lightly doped devices to junctionless transistors.展开更多
基金Project supported by the National Basic Research Program of China (No. 2007CB209400)the National Nature Fond (No. 50774077 and 50774081)the National Fond of Author of Doctor Thesis (100760)
文摘For non-asymmetrical bending problems of elastic annular plates, the exact solutions are not fond. To bending problems of infinite annular plate with two different boundary conditions, based on the boundary integral formula,the natural boundary integral equation for the boundary value problems of the biharmonic equation and the condition of bending moment in infinity,bending solutions under non-symmetrical loads are gained by the Fourier series and convolution formulae. The formula for the solutions has nicer convergence velocity and high computational accuracy, and the calculating process is simpler. Solutions of the given examples are compared with the finite element method. The textual solutions of moments near the loads are better than the finite element method to the fact that near the concentrative loads the inners forces trend to infinite.
基金Acknowledgments. We would like to thank the reviewers for their valuable comments which improve the paper. This research is partly supported by the National Natural Science Foundation of China contact/grant number： 11071109 Foundation for Innovative Program of Jiangsu Province, contact/grant number： CXZZ12_0383 and CXZZ11_0870.
文摘Based on the Kirchhoff transformation and the natural boundary element method, we investigate a coupled natural boundary element method and finite element method for quasi-linear problems in a bounded or unbounded domain with a concave angle. By the principle of the natural boundary reduction, we obtain natural integral equation on circular arc artificial boundaries, and get the coupled variational problem and its numerical method. Moreover, the convergence of approximate solutions and error estimates are obtained. Finally, some numerical examples are presented to show the feasibility of our method. Our work can be viewed as an extension of the existing work of H.D. Han et al..
文摘Subthreshold conduction is governed by the potential distribution. We focus on full two-dimensional（2D） analytical modeling in order to evaluate the 2D potential profile within the active area of Fin FET structure.Surfaces and interfaces, which are key nanowire elements, are carefully studied. Different structures have different boundary conditions, and therefore different effects on the potential distributions. A range of models in Fin FET are reviewed in this paper. Parabolic approximation and evanescent mode are two different basic math methods to simplify the Poisson＇s equation. Both superposition method and parabolic approximation are widely used in heavily doped devices. It is helpful to learn performances of MOSFETs with different structures. These two methods achieved improvement to face different structures from heavily doped devices or lightly doped devices to junctionless transistors.
