A new integral inequality with power nonlinearity is obtained,which generalizes some extensions of L. Ou-Iang's inequality given by B.G. Pachpatte. Discrete analogy of the new integral inequality and some applica...A new integral inequality with power nonlinearity is obtained,which generalizes some extensions of L. Ou-Iang's inequality given by B.G. Pachpatte. Discrete analogy of the new integral inequality and some application examples are also indicated.展开更多
In this paper, we study a kind of boundary value problem for volterra functional differential equation:ε x″(t)=f(t,ε)x′(t)+g(t,x(t),(t),x(t-τ),ε), t∈(0,1) x(t)=(t,ε), t∈, x(1)=ψ(ε) Using the theory of dif...In this paper, we study a kind of boundary value problem for volterra functional differential equation:ε x″(t)=f(t,ε)x′(t)+g(t,x(t),(t),x(t-τ),ε), t∈(0,1) x(t)=(t,ε), t∈, x(1)=ψ(ε) Using the theory of differential inequality, we prove the existence of the solution and give a uniformly valid asympototic expansions of the solution. Meanwhile, an estimation of the derivative solution is given as well.展开更多
We consider the nearest-neighbor model on the finite tree T with generator L. We obtain a twosided estimate of the spectral gap by factor 2. We also identify explicitly the Lipschitzian norm of the operator(-L)^(-1) i...We consider the nearest-neighbor model on the finite tree T with generator L. We obtain a twosided estimate of the spectral gap by factor 2. We also identify explicitly the Lipschitzian norm of the operator(-L)^(-1) in propriate functional space. This leads to the identification of the best constant in the generalized Cheeger isoperimetric inequality on the tree, and to transportation-information inequalities.展开更多
This paper focuses on boundary stabilization of a one-dimensional wave equation with an unstable boundary condition,in which observations are subject to arbitrary fixed time delay.The observability inequality indicate...This paper focuses on boundary stabilization of a one-dimensional wave equation with an unstable boundary condition,in which observations are subject to arbitrary fixed time delay.The observability inequality indicates that the open-loop system is observable,based on which the observer and predictor are designed:The state of system is estimated with available observation and then predicted without observation.After that equivalently the authors transform the original system to the well-posed and exponentially stable system by backstepping method.The equivalent system together with the design of observer and predictor give the estimated output feedback.It is shown that the closed-loop system is exponentially stable.Numerical simulations are presented to illustrate the effect of the stabilizing controller.展开更多
The centroafhine Minkowski problem is studied, which is the critical case of the L_p-Minkowski problem. It admits a variational structure that plays an important role in studying the existence of solutions.In this pap...The centroafhine Minkowski problem is studied, which is the critical case of the L_p-Minkowski problem. It admits a variational structure that plays an important role in studying the existence of solutions.In this paper, we find that there is generally no maximizer of the corresponding functional for the centroaffine Minkowski problem.展开更多
基金the Natural Science Foundation of Guangdong Pronvincial.
文摘A new integral inequality with power nonlinearity is obtained,which generalizes some extensions of L. Ou-Iang's inequality given by B.G. Pachpatte. Discrete analogy of the new integral inequality and some application examples are also indicated.
文摘In this paper, we study a kind of boundary value problem for volterra functional differential equation:ε x″(t)=f(t,ε)x′(t)+g(t,x(t),(t),x(t-τ),ε), t∈(0,1) x(t)=(t,ε), t∈, x(1)=ψ(ε) Using the theory of differential inequality, we prove the existence of the solution and give a uniformly valid asympototic expansions of the solution. Meanwhile, an estimation of the derivative solution is given as well.
基金National Natural Science Foundation of China (Grant Nos. 11271294, 11101040, 11431014 and 11371283)Beijing Youth Excellent Talents Program (Grant No. 0264)+1 种基金National Creative Group under Beijing Normal University 985 Projectsthe Fundamental Research Funds for the Central Universities and le Project ANR EVOL
文摘We consider the nearest-neighbor model on the finite tree T with generator L. We obtain a twosided estimate of the spectral gap by factor 2. We also identify explicitly the Lipschitzian norm of the operator(-L)^(-1) in propriate functional space. This leads to the identification of the best constant in the generalized Cheeger isoperimetric inequality on the tree, and to transportation-information inequalities.
基金supported by the National Natural Science Foundation of China under Grant No.61203058the Training Program for Outstanding Young Teachers of North China University of Technology under Grant No.XN131+1 种基金the Construction Plan for Innovative Research Team of North China University of Technology under Grant No.XN129the Laboratory construction for Mathematics Network Teaching Platform of North China University of Technology under Grant No.XN041
文摘This paper focuses on boundary stabilization of a one-dimensional wave equation with an unstable boundary condition,in which observations are subject to arbitrary fixed time delay.The observability inequality indicates that the open-loop system is observable,based on which the observer and predictor are designed:The state of system is estimated with available observation and then predicted without observation.After that equivalently the authors transform the original system to the well-posed and exponentially stable system by backstepping method.The equivalent system together with the design of observer and predictor give the estimated output feedback.It is shown that the closed-loop system is exponentially stable.Numerical simulations are presented to illustrate the effect of the stabilizing controller.
基金supported by National Natural Science Foundation of China (Grant No 11401527)
文摘The centroafhine Minkowski problem is studied, which is the critical case of the L_p-Minkowski problem. It admits a variational structure that plays an important role in studying the existence of solutions.In this paper, we find that there is generally no maximizer of the corresponding functional for the centroaffine Minkowski problem.