Nonrecursive statistics for integral equation solutions

Recursive schemes are often used to solve complex governing equations in mathematical physics. It is demonstrated that such an approach poses unique difficulties when applied to stochastic integral equations. Each subsequent term in the series requires knowledge of higher order statistics than evaluated for the previous term, and thus no true recursion exists. In effect, even if the equation is linear, it is nonlinear in stochastic quantities. The complexity of each term prevents the evaluation of more than a few terms in the iteration, even when symbolic manipulation codes such as MACSYMA are used.     

Asymptotic stability of solitary wave solutions to the regularized long-wave equation

We study the asymptotic stability of solitary wave solutions to the regularized long-wave equation (RLW) in . RLW is an equation which describes the long waves in water. To prove the result, we make use of the monotonicity of the local H¹-norm and apply the Liouville property of (RLW) as in Merle and Martel (J. Math. Pures Appl. 79 (2000) 339; Arch. Rational Mech. Anal. 157 (2001) 219).     

基于迭代正则化高斯-牛顿法的非线性Urysohn积分方程数值解

非线性Urysohn积分方程在许多领域中都有广泛的应用,但由于该方程具有不适定性的特点,数据的微小扰动可能导致解的巨大变化,给数值求解带来很大困难.为了获得稳定的、准确的数值解,本文利用迭代正则化高斯-牛顿法对此方程进行求解,给出了利用Sigmoid-型函数确定迭代正则化参数的方法.对一类重力测定问题进行了数值模拟,将得到的数值解和相应的精确解作比较.结果表明,本文提出的方法在求解非线性Urysohn积分方程时是可行的也是有效的.     

Analytical formulation of meshless local integral equation method

In this paper, the exact forms of integrals in the meshless local boundary integral equation method are derived and implemented for elastostatic problems. A weak form for a set of governing equations with a unit test function or polynomial test functions is transformed into local integral equations. Each node has its own support domain and is surrounded by a local integral domain with different shapes of boundaries. The meshless approximation based on the radial basis function (RBF) is employed for the implementation of displacements. A completed set of closed forms of the local boundary integrals are obtained. As there are no numerical integrations to be carried out the computational time is significantly reduced. Three examples are presented to demonstrate the application of this approach in solid mechanics.     

On some solutions to the Chapman-Kolmogorov integral equation

By applying integral transformations, we obtain some solutions to the Chapman-Kolmogorov equation. These are illustrated by examples.     

Classification of solutions for an integral equation

Let n be a positive integer and let 0 < α < n. Consider the integral equation We prove that every positive regular solution u(x) is radially symmetric and monotone about some point and therefore assumes the form with some constant c = c(n, α) and for some t > 0 and x₀ ? ?ⁿ. This solves an open problem posed by Lieb 12 . The technique we use is the method of moving planes in an integral form, which is quite different from those for differential equations. From the point of view of general methodology, this is another interesting part of the paper. Moreover, we show that the family of well‐known semilinear partial differential equations is equivalent to our integral equation (0.1), and we thus classify all the solutions of the PDEs. © 2005 Wiley Periodicals, Inc.     

Existence and uniqueness of solutions for singular integral equation

Using the mixed monotone method we establish existence and uniqueness results for a singular integral equation. The theorem obtained is very general and complements previous known results. The work was supported by the National Natural Science Foundation of China (No.10571021 and No.10701020) and Key Laboratory for Applied Statistics of MOE(KLAS) and Subject Foundation of Harbin University (No. HXK200714).     

On the numerical solutions of integral equation of mixed type

Sufficient conditions for oscillation of all solutions of a class of second-order quasilinear delay differential equations with fixed moments of impulse effect are found.     

Some linearly and non-linearly implicit schemes for the numerical solutions of the regularized long-wave equation

In this paper, we present some linearly implicit and non-linearly implicit schemes for investigating the numerical solutions of the regularized long-wave equation. Numerical experiments indicate that all the present schemes can give satisfactory numerical solutions. Meanwhile, numerical results also confirm the excellent conservations of three invariants in long time computations.     

Analytical and numerical solutions of the density dependent Nagumo telegraph equation

In this paper, we obtained analytical and numerical solutions to a class of density dependent diffusion equations with memory–delay effect. This is a generalization of the density dependent diffusion Nagumo equation we studied recently [R.A. Van Gorder, K. Vajravelu, Physics Letters A 372 (2008) 5152]. Furthermore, we obtained series solutions for various strengths of the density dependence along with bounds on the range of the convergence. The numerical solutions are obtained by the Runge–Kutta–Fehlberg 45 method. The dependence of the traveling wave solutions on various parameters, particularly the memory–delay term, is discussed.     

Remarks on non-trivial solutions of a Volterra integral equation

In this paper non-linear integral equations describing shock wave phenomena are presented. Some necessary and sufficient conditions for the existence of non-trivial solutions to equations of this type are given.     

Nondecreasing solutions of a quadratic singular Volterra integral equation

We study the existence of nondecreasing solutions of a quadratic singular Volterra integral equation in the space of continuous functions on bounded interval. The main tool utilized in our considerations is the technique associated with certain measure of noncompactness related to monotonicity. The results obtained in the paper may be applied to a wide class of singular Volterra integral equations.     

Monotonic solutions of a perturbed quadratic fractional integral equation

We present an existence theorem for monotonic solutions of a perturbed quadratic fractional integral equation in C[0,1]. The concept of a measure of noncompactness and a fixed point theorem due to Darbo are the main tools in carrying out our proof. Finally, we give an example for indicating the natural realizations of our abstract result presented in the paper.     

Weighted integral inequalities for solutions of the A-harmonic equation

We prove the parametric versions of -weighted integral inequalities for differential forms satisfying the A-harmonic equation. These results can be considered as extensions of the classical inequalities for Sobolev functions.