Asymptotics for the Korteweg-de Vries-Burgers Equation

We study large time asymptotics of solutions to the Korteweg-de Vries-Burgers equation ut＋uux-uxx＋uxxx=0,x∈R,t〉0. We are interested in the large time asymptotics for the case when the initial data have an arbitrary size. We prove that if the initial data u0 ∈H^s （R）∩L^1 （R）, where s 〉 -1/2, then there exists a unique solution u （t, x） ∈C^∞ （（0,∞）;H^∞ （R）） to the Cauchy problem for the Korteweg-de Vries-Burgers equation, which has asymptotics u（t）=t^-1/2fM（（·）t^-1/2）＋0（t^-1/2） as t →∞, where fM is the self-similar solution for the Burgers equation. Moreover if xu0 （x） ∈ L^1 （R）, then the asymptotics are true u（t）=t^-1/2fM（（·）t^-1/2）＋O（t^-1/2-γ） where γ ∈ （0, 1/2）.     

On the Solution of the Feigenbaum's Functional Equation

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Exact Vacuum Solutions to the Einstein Equation

In this paper,the author presents a framework for getting a series of exact vacuum solutions to the Einstein equation.This procedure of resolution is based on a canonical form of the metric.According to this procedure,the Einstein equation can be reduced to some 2-dimensional Laplace-like equations or rotation and divergence equations, which are much convenient for the resolution.     

On the Linearized Balescu–Lenard Equation

The Balescu–Lenard equation from plasma physics is widely considered to include a highly accurate correction to Landau's fundamental collision operator. Yet so far it has seen very little mathematical study. We perform an extensive linearized analysis of this equation, which includes determining the asymptotic behavior of the new components of the linearized operator and establishing time decay rates for the linearized equation.     

MSPRK Methods for the Korteweg-de Vries Equation

We consider the Korteweg-de Vries (KdV) equation in the form ut+uux+uxxx=0(1) which is a nonlinear hyperbolic equation and has smooth solutions for all the time. There are a vast of results can be found in the literature for this equation, both theoretical and numerical. However, several good reasons account for needs of another numerical study of this equation are listed in[1]. Among them, the most convincing one might be that the wave equations have the multi-symplectic structure (cf. [2]), and the KdV equation is therefore a     

On the Existence of Solutions of Poisson Equation and Poincaré–Lelong Equation

One of the main goals of this paper is to solve the Poincaré–Lelong equation on a class of Kähler manifolds with nonnegative holomorphic bisectional curvature, $\mathrm{Ric}(x)\geq \left(a\ln\ln\left(10+r(x)\right)\right)\Big/\big.\left(\left(1+r^2(x)\right)\ln(10+r(x))\right)One of the main goals of this paper is to solve the Poincaré–Lelong equation on a class of K?hler manifolds with nonnegative holomorphic bisectional curvature, for some a > 67(n + 4)². We will also study the Poisson equation on complete noncompact manifolds which satisfy volume doubling and Poincaré inequality.     

A Note on the Viscous Cahn-Hilliard Equation

In this note, we study the global existence of classical solutions for the viscous Cahn-Hilliard equation with spatial dimension n ≤ 5. Based on the Schauder type estimates and energy estimates, we establish the global existence of classical solutions.     

On the Solution of the Operator Equation AT-TB=S

Let H, K be two Hilbert spaces over complex field A. Let B(HI, K) denote the set of all bounded linear operators from H to K. If H=K, we write B(H) instead of B(H, K). Consider the operator defined by the equation     

On the Periodic Solution to the Newtonian Equation of Motion

Consider the system of ordinary differential equation u”(t)+grad G(u(t))=p(t),(1)where p:R→R”is continuous and 2π periodic and G:R~π→R has continuous secondorder partial derivatives.The system can be interpreted physically as the Newto-nian equation of motion of a mechanical system subject to conservative internalforces and the periodic external forces.     

On the Generalized Upwind Scheme for the Neutron Transport Equation

Let Ω be a convex domain in the (x, y) plane with boundary . Denote by n=(n_x, n_y) the outward unit normal to. Consider the following problem (1) (2) where μ, v are real parameters and σ=σ(x, y) satisfies σ≥σ_0>0. Equation (1) arises in neutron transport theory. In this paper, we study theoretically the stability and convergence properties of a discontinuous Galerkin approximation to prob-     

On the Approximate Functional Equation of Riemann zeta-Function

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Continual Distribution for the Bryan–Pidduck Equation

Ukrainian Mathematical Journal - For a nonlinear kinetic Boltzmann equation that describes the model of rough spheres, we construct its approximate solution in the form of a continual distribution...     

On the Equation and the Number of Solution of Znam's Problem

§1. In 1972,St.Znam posed the problem whether for every s>1 thereexist integers x_i>1,i=1,…,s such that x_i is a proper divisor of the numberx_1…x_(i-1)x_(i 1)…x_s 1 for i=1,…, s.Without loss of generality, we may assume1相似文献   

Extremum Problem for the Wiener–Hopf Equation

The extremum problem for the Wiener–Hopf equation obtained by replacing the condition u(x) = 0, x < 0, by the condition of the minimum of the quadratic functional of the function u(x)exp(–x), – < x < , is solved in closed form.     

Nonlocal Reductions of the Ablowitz–Ladik Equation

Our purpose is to develop the inverse scattering transform for the nonlocal semidiscrete nonlinear Schrödinger equation (called the Ablowitz–Ladik equation) with \(\mathcal{PT}\) symmetry. This includes the eigenfunctions (Jost solutions) of the associated Lax pair, the scattering data, and the fundamental analytic solutions. In addition, we study the spectral properties of the associated discrete Lax operator. Based on the formulated (additive) Riemann–Hilbert problem, we derive the one- and two-soliton solutions for the nonlocal Ablowitz–Ladik equation. Finally, we prove the completeness relation for the associated Jost solutions. Based on this, we derive the expansion formula over the complete set of Jost solutions. This allows interpreting the inverse scattering transform as a generalized Fourier transform.     

Wave Breaking of the Camassa–Holm Equation

This paper gives a new and direct proof for McKean’s theorem (McKean in Asian J. Math. 2:867–874, 1998) on wave breaking of the Camassa–Holm equation. The blow-up profile is also analyzed.     

On the Existence of Harmonic Solutions of the Forced Lienard Equation

In this paper, we present a method to study the existence of the harmonicsolutions of the forcde Lienard equation′s equivalent system     

On the Matrix Equation A~2=J

An unsolved problem is to enumerate all solutions for the matrix equation A~2=Jwhere A is an n×n (0.1)-matrix and J is the n×n matr trix with every entry being 1. Here we present a family of n×n generalized circulant (0.1)-matrices each of whose square is J. Moreover. the existence of this family is unique up to permutational similarity.     

On the Stability of the Functional Equation in Matrix β-Normed Spaces

In this paper we introduce the matrix β-normed space and study the stability of the additive-quadratic type functional equation and the Pexider type functional equation in this type of spaces.