In this paper we deal with the initial boundary value problem for two classes of reaction diffusion systems with two source terms in bounded domain. Under some assumptions on the exponents and the initial data, applyi...In this paper we deal with the initial boundary value problem for two classes of reaction diffusion systems with two source terms in bounded domain. Under some assumptions on the exponents and the initial data, applying the comparison principle, the maximum prin- ciple and the supersolution-subsolution method, we prove the global existence and blow up of solutions. We also establish some upper blow up rates.展开更多
We study the Cauchy problem of strongly damped Klein-Gordon equation. Global existence and asymptotic behavior of solutions with initial data in the potential well are derived. Moreover, not only does finite time blow...We study the Cauchy problem of strongly damped Klein-Gordon equation. Global existence and asymptotic behavior of solutions with initial data in the potential well are derived. Moreover, not only does finite time blow up with initial data in the unstable set is proved, but also blow up results with arbitrary positive initial energy are obtained.展开更多
Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are ...Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are derived. The results are valid for initial data with arbitrary high positive energy. The proofs are based on the concave method and new sign preserving functionals.展开更多
Li et al. in [3] obtained blow-up results for a system of Petrovskey equations in some different cases. In this article we obtain lower bounds for the blow up time under some considerations on initial data.
We investigate sharp conditions for boundary and interior gradient estimates of continuous viscosity solutions to fully nonlinear, uniformly elliptic equations under Dirichlet boundary conditions. When these condition...We investigate sharp conditions for boundary and interior gradient estimates of continuous viscosity solutions to fully nonlinear, uniformly elliptic equations under Dirichlet boundary conditions. When these conditions are violated, there can be blow up of the gradient in the interior or on the boundary of the domain. In particular we de- rive sharp results on local and global Lipschitz continuity of continuous viscosity solutions under more general growth conditions than before. Lipschitz regularity near the boundary allows us to predict when the Dirichlet condition is satisfied in a classical and not just in a viscosity sense, where detachment can occur. Another consequence is this： if interior gra- dient blow up occurs, Perron-type solutions can in general become discontinuous, so that the Dirichlet problem can become unsolvable in the class of continuous viscosity solutions.展开更多
For the nonlinear wave equation in R-N x R+ (N greater than or equal to 2): partial derivative(2)u(x,t)/partial derivative(t)(2) - a partial derivative/partial derivative(xi)(a/(x) partial derivative/partial derivativ...For the nonlinear wave equation in R-N x R+ (N greater than or equal to 2): partial derivative(2)u(x,t)/partial derivative(t)(2) - a partial derivative/partial derivative(xi)(a/(x) partial derivative/partial derivative(xi)u) = \u\(p-1 u,) in 1980 Kato proved the solution of Cauchy problem may blow rtp infinite time if 1 < p less than or equal to N + 1/N - 1. In the present work his result allowing 1 < p less than or equal to N + 3/N - 1 is improved by using different estimates.展开更多
基金supported by the National Natural Science Foundation of China(11471087)the China Postdoctoral Science Foundation(2013M540270)+1 种基金the Heilongjiang Postdoctoral Foundation(LBH-Z13056,LBHZ15036)the Fundamental Research Funds for the Central Universities
文摘In this paper we deal with the initial boundary value problem for two classes of reaction diffusion systems with two source terms in bounded domain. Under some assumptions on the exponents and the initial data, applying the comparison principle, the maximum prin- ciple and the supersolution-subsolution method, we prove the global existence and blow up of solutions. We also establish some upper blow up rates.
基金supported by the National Natural Science Foundation of China (11101102)Ph.D. Programs Foundation of Ministry of Education of China (20102304120022)+3 种基金the Support Plan for the Young College Academic Backbone of Heilongjiang Province (1252G020)the Natural Science Foundation of Heilongjiang Province (A201014)Science and Technology Research Project of Department of Education of Heilongjiang Province (12521401)Foundational Science Foundation of Harbin Engineering University and Fundamental Research Funds for the Central Universities (HEUCF20131101)
文摘We study the Cauchy problem of strongly damped Klein-Gordon equation. Global existence and asymptotic behavior of solutions with initial data in the potential well are derived. Moreover, not only does finite time blow up with initial data in the unstable set is proved, but also blow up results with arbitrary positive initial energy are obtained.
基金partially supported by Grant No.DFNI I-02/9 of the Bulgarian Science Fund
文摘Finite time blow up of the solutions to Boussinesq equation with linear restoring force and combined power nonlinearities is studied. Sufficient conditions on the initial data for nonexistence of global solutions are derived. The results are valid for initial data with arbitrary high positive energy. The proofs are based on the concave method and new sign preserving functionals.
文摘Li et al. in [3] obtained blow-up results for a system of Petrovskey equations in some different cases. In this article we obtain lower bounds for the blow up time under some considerations on initial data.
基金financed by the Alexander von Humboldt Foundationcontinued in March 2009 at the Mathematisches Forschungsinstitut Oberwolfach in the "Research in Pairs"program
文摘We investigate sharp conditions for boundary and interior gradient estimates of continuous viscosity solutions to fully nonlinear, uniformly elliptic equations under Dirichlet boundary conditions. When these conditions are violated, there can be blow up of the gradient in the interior or on the boundary of the domain. In particular we de- rive sharp results on local and global Lipschitz continuity of continuous viscosity solutions under more general growth conditions than before. Lipschitz regularity near the boundary allows us to predict when the Dirichlet condition is satisfied in a classical and not just in a viscosity sense, where detachment can occur. Another consequence is this： if interior gra- dient blow up occurs, Perron-type solutions can in general become discontinuous, so that the Dirichlet problem can become unsolvable in the class of continuous viscosity solutions.
基金the National Natural Science Foundation of China
文摘For the nonlinear wave equation in R-N x R+ (N greater than or equal to 2): partial derivative(2)u(x,t)/partial derivative(t)(2) - a partial derivative/partial derivative(xi)(a/(x) partial derivative/partial derivative(xi)u) = \u\(p-1 u,) in 1980 Kato proved the solution of Cauchy problem may blow rtp infinite time if 1 < p less than or equal to N + 1/N - 1. In the present work his result allowing 1 < p less than or equal to N + 3/N - 1 is improved by using different estimates.
