被捕食者带有第三边值的捕食模型的正稳态解的存在性

该文研究了一类被捕食者带有第三边值的捕食模型. 首先获得了它存在正稳态解的充要条件是a>mb+d₁λ₁; 然后研究了它的正稳态解的局部稳定性和唯一性;最后讨论了充分大的扩散参数对它的正稳态解的存在性的影响.     

一类非线性高阶波动方程的初边值问题

该文研究一类非线性高阶波动方程u_tt－a_1^Uxx+a_₂u_x4+a₃u_x4_tt=φ(u_{x ⁾}x+f(u,u_x,u_xxu_xxx,u_x4)的初边值问题.证明整体古典解的存在唯一性并给出古典解爆破的充分条件.     

u0 - 凹算子的不动点定理及其应用

该文利用锥的性质和单调迭代技巧讨论了u₀ - 凹算子正不动点的存在唯一性,所得结论改进并推广了已有的相关结果. 作为应用, 该文研究了一类Hammerstein积分方程正解的存在唯一性.     

拟线性抛物方程组具有界面外推的并行本性差分方法

构造了拟线性抛物型方程组初边值问题的一类具有界面外推的并行本性差分格式. 为给出子区域间界面上的值或者与界面相邻点处的值,给出了两类时间外推的方式, 得到了二阶精度无条件稳定的并行差分格式. 并且不作启示性假定,证明了所构造的并行差分格式的离散向量解的存在性和 唯一性. 而且在格式的离散向量解对原始问题的已知离散数据连续依赖的意义下, 证明了并行差分格式的解按离散W^(2,1)₂(Q_Δ)范数是无条件稳定的.最后证明了具有界面外推的并行本性差分格式的离散向量解收敛到原始拟线性抛物问题的唯一广义解. 给出了数值例子,数值结果表明所构造的格式是无条件稳定的, 具有二阶精度,且具有高度并行性.     

非局部的退化抛物型方程组的解的爆破和整体存在性

该文采用弱上下解方法以及正则化的技巧,研究了一类非局部的退化的抛物型方程组的解的爆破和整体存在性,给出了方程组的解的爆破指标p_c=(p₁+p₂)(q₁+q₂)-mn,证得当p_c<0时,对任意的初值,方程组的解整体存在;当p_c>0时,对充分大的初值,解在有限时刻爆破,对充分小的初值,解整体存在;当p_c=0时,若区域充分小,则方程组存在非负整体解,若区域包含了一个充分大的球, 则解在有限时刻爆破.     

非线性抛物椭圆方程组的正则解和奇异解

该文用单模方法在Lorentz空间研究了抛物椭圆方程组奇异解和正则解的存在性, 其中初值属于Lorentz空间L^{n/2,∞ ₍}Rⁿ), n≥ 3. 利用时间加权的Lorentz空间, 还得到了其正则解. 此外, 如果初值满足自相似结构, 也得到了自相似解的存在性.     

关于广义Li&#233;nard系统解的唯一性

研究了广义Li&#233;nard系统初值问题解的唯一性问题.利用李普希兹条件和隐函数定理,我们得到了此系统解的存在唯一性定理,推广了相应的结果.     

具有随机扰动的Logistic方程正解的存在唯一性、全局吸引性及其参数的极大似然估计

讨论了随机化Logistic方程 其初值N(0)=N₀且0<N₀ <K是一个随机变量.主要研究了正解的存在性、唯一性及全局吸引性,并给出了方程中参数的极大似然估计.     

一类非线性四阶波动方程的位势井方法

该文讨论非线性波动方程u_{tt}+u_{xxxx}=σ(u_x)_x+f(x,t)的初边值问题.证明了整体弱解的存在性,还证明了整体广义解的存在唯一性和整体古典解的存在唯一性.     

随机广义Ginzburg-Landau方程的吸引子

可以按轨道得到带白噪声的随机广义Ginzburg-Landau方程的唯一解并且能够验证该解可以产生随机系统, 从而证明了该随机系统在H¹₀中存在整体随机吸引子.     

Pseudo almost automorphic solutions for dissipative differential equations in Banach spaces

This work aims to study the existence and uniqueness of pseudo compact almost automorphic solution for some dissipative ordinary and functional differential equations. We prove the existence and uniqueness of pseudo compact almost automorphic solution for dissipative differential equations in Banach spaces and then we apply this result to show the existence of pseudo compact almost automorphic solutions for some functional differential equations.     

The ergodicity of stochastic partial differential equations with Lévy jump

In this article, the authors prove the uniqueness in law of a class of stochastic equations in infinite dimension, then we apply it to establish the existence and uniqueness of invariant measure of the generalized stochastic partial differential equation perturbed by Lévy process.     

On the Unique Solvability of the Nonlinear Systems in MDBM

1.IntroductionConsiderthefollowinginitialva1ueprobleminordinarydifferentialequationsy,(t)=f(t,y(t)),y(to)=Yo,(1'1)whereyoER',f:RxR'toR',iscontinuous.Theapproximatesolutionto(1.1)canbeobtainedbythemultiderivativeblockmethod(MDBM)withsecondorderderivatives:wherei=1,'9k,ynER',fn:=f(t.,y.)ER',andf;'):=df(t.,y.)/dteR'areknownvectors.Itisprovedthatthereexistaijjbij,oliandd2i,i,j=1,2,'1k,suchthat(1.2)convergeswithorderp=2k 2(see[l]),andisA-stablefork55(see[5]).Tocomputetheapproxin1atesolut…     

Optimal control problems constrained by the stochastic Navier–Stokes equations with multiplicative Lévy noise

We consider the controlled stochastic Navier–Stokes equations in a bounded multidimensional domain, where the noise term allows jumps. In order to prove existence and uniqueness of an optimal control w.r.t. a given control problem, we first need to show the existence and uniqueness of a local mild solution of the considered controlled stochastic Navier–Stokes equations. We then discuss the control problem, where the related cost functional includes stopping times dependent on controls. Based on the continuity of the cost functional, we can apply existence and uniqueness results provided in [4], which enables us to show that a unique optimal control exists.     

Problem with shifts in interior characteristics for equations of mixed elliptic-hyperbolic type with a singular coefficient

We consider a problem with local shift conditions on a segment of the degeneration line and with shifts in interior characteristics of the equation. The uniqueness of the solution is proved with the use of the extremum principle. To prove the existence of a solution, we apply the theory of singular integral equations and Fredholm integral equations.     

Initial boundary value problem for modified Zakharov equations

In this paper the authors consider the existence and uniqueness of the solution to the initial boundary value problem for a class of modified Zakharov equations, prove the global existence of the solution to the problem by a priori integral estimates and Galerkin method.     

Global Existence and Uniqueness of Solutions to Evolution p-Laplacian Systems with Nonlinear Sources

This paper presents the global existence and uniqueness of the initial and boundary value problem to a system of evolution p-Laplacian equations coupled with general nonlinear terms. The authors use skills of inequality estimation and themethod of regularization to construct a sequence of approximation solutions, hence obtain the global existence of solutions to a regularized system. Then the global existence of solutions to the system of evolution p-Laplacian equations is obtained with the application of a standard limiting process. The uniqueness of the solution is proven when the nonlinear terms are local Lipschitz continuous.     

Asymptotic distributions of solutions of ordinary differential equations with wide band noise inputs: approximate invariant measures

Systems of Wick stochastic differential equations are studied. Using an estimate on the Wick product we apply Picard iteration to prove a general existence and uniqueness theorem for systems of Wick stochastic differential equations. We also show the solution is stable with respect to perturbations of the noise. This result is used to show that the solution of a linear system of Wick stochastic differential equations driven by smoothed Brownian motion tends to the solution of the corresponding It equation as the smoothed process tends to Brownian motion     

Stochastic Wave Equations with Memory

The authors show the existence and uniqueness of solution for a class of stochastic wave equations with memory. The decay estimate of the energy function of the solution is obtained as well.     

Existence and uniqueness of local solutions to a class of quasilinear degenerate parabolic systems

In this paper, the authors study an initial and boundary value problem to a system of evolution p-Laplacian equations coupled with general nonlinear terms. The authors use the method of regularization to construct a sequence of approximation solutions with the help of monotone iteration technique and hence obtain the existence of solutions to a regularized system of equations. Then the existence of solutions to the system of evolution p-Laplacian equations is obtained with the use of a standard limiting process. The uniqueness of the solution is also proven.