A generalized Fisher equation （GFE） relates the time derivative of the average of the intrinsic rate of growth to its variance. The exact mathematical result of the GFE has been widely used in population dynamics an...A generalized Fisher equation （GFE） relates the time derivative of the average of the intrinsic rate of growth to its variance. The exact mathematical result of the GFE has been widely used in population dynamics and genetics, where it originated. Many researchers have studied the numerical solutions of the GFE, up to now. In this paper, we introduce an element-free Galerkin （EFG） method based on the moving least-square approximation to approximate positive solutions of the GFE from population dynamics. Compared with other numerical methods, the EFG method for the GFE needs only scattered nodes instead of meshing the domain of the problem. The Galerkin weak form is used to obtain the discrete equations, and the essential boundary conditions are enforced by the penalty method. In comparison with the traditional method, numerical solutions show that the new method has higher accuracy and better convergence. Several numerical examples are presented to demonstrate the effectiveness of the method.展开更多
In this work, we consider a Fisher and generalized Fisher equations with variable coefficients. Using truncated Painleve expansions of these equations, we obtain exact solutions of these equations with a constraint on...In this work, we consider a Fisher and generalized Fisher equations with variable coefficients. Using truncated Painleve expansions of these equations, we obtain exact solutions of these equations with a constraint on the coefficients a（t） and b（t）.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 11072117)the Natural Science Foundation of Ningbo City (Grant Nos. 2012A610038 and 2012A610152)+1 种基金the Scientific Research Fund of Education Department of Zhejiang Province,China (Grant No. Z201119278)K.C. Wong Magna Fund in Ningbo University
文摘A generalized Fisher equation （GFE） relates the time derivative of the average of the intrinsic rate of growth to its variance. The exact mathematical result of the GFE has been widely used in population dynamics and genetics, where it originated. Many researchers have studied the numerical solutions of the GFE, up to now. In this paper, we introduce an element-free Galerkin （EFG） method based on the moving least-square approximation to approximate positive solutions of the GFE from population dynamics. Compared with other numerical methods, the EFG method for the GFE needs only scattered nodes instead of meshing the domain of the problem. The Galerkin weak form is used to obtain the discrete equations, and the essential boundary conditions are enforced by the penalty method. In comparison with the traditional method, numerical solutions show that the new method has higher accuracy and better convergence. Several numerical examples are presented to demonstrate the effectiveness of the method.
文摘In this work, we consider a Fisher and generalized Fisher equations with variable coefficients. Using truncated Painleve expansions of these equations, we obtain exact solutions of these equations with a constraint on the coefficients a（t） and b（t）.
