In quantum theory Hamilton operators with spininteractions have a long history [1 – 5]. Triple spin interaction have been studied by several authors [6 – 19]. Iglói [6] investigated an Ising model with three-spin interaction by finite-size scaling and applying free boundary conditions. Vanderzande and Iglói [7] studied the critical behaviour and logarithmic corrections of a quantum model with t...

in this paper we study the boundary layer problems in which boundary conditions are non-local. here we try to find the necessary conditions by the help of fundamental solution to the given adjoint equation. by getting help from these conditions, at first the boundary condition is changed from non-local to local. the main aim of this paper is to identify the location of the boundary layer. in ot...

We establish an abstract infinite dimensional KAM theorem dealing with unbounded perturbation vector-field, which could be applied to a large class of Hamiltonian PDEs containing the derivative ∂x in the perturbation. Especially, in this range of application lie a class of derivative nonlinear Schrödinger equations with Dirichlet boundary conditions and perturbed Benjamin-Ono equation with peri...

the effect of boundary conditions on the solution of the inverse problem of identifying the geometry and location of a cavity inside an elastic solid body using displacement measurements obtained from a tension test is investigated. the boundary elements method (bem) coupled with the genetic algorithm (ga) and the conjugate gradient method (cgm) are implemented in this identification problem. a...

Several collaborations have employed O(a) improved Wilson fermions, following the nonperturbative determination of the clover coefficient csw for Nf = 2 flavours in the range β ≥ 5.2 [1]. UKQCD, QCDSF and JLQCD perform simulations on physically large volumes (L ∼ 1.5 fm) using periodic boundary conditions [2–4], whereas ALPHA use Schrödinger functional (SF) boundary conditions on small volumes ...

In this paper, we consider second order differential inclusions with periodic boundary conditions. We obtain the existence of positive solutions and of continuous branches of positive solutions.

I derive a general set of boundary conditions for quasiclassical transport theory of metals and superconductors that is valid for equilibrium and nonequilibrium situations and includes multiband systems, weakly and strongly spin-polarized systems, and disordered systems. The formulation is in terms of the normal state scattering matrix. Various special cases for boundary conditions are known in...

We study controllability of 2D defocusing cubic Schroedinger equation under periodic boundary conditions and control applied via source term (additively). The source term is a linear combination of few complex exponentials (modes) with time-variant coefficients controls. We manage to prove that controlling just 4 modes one can achieve controllability of this equation in any finite-dimensional p...

We study two types of asymptotic problems whose common feature and difficultyis to exhibit oscillating Dirichlet boundary conditions : the main contribution of this article is to show how to recover the Dirichlet boundary condition for the limiting equation. These two types of problems are (i) periodic homogenization problems for fully nonlinear, second-order elliptic partial differential equat...

The method of quasilinearization of Bellman and Kalaba [2] has been extended, refined, and generalized when the forcing function is the sum of a convex and concave function using coupled lower and upper solutions. This method is now known as the method of generalized quasilinearization. It has all the advantages of the quasilinearization method such that the iterates are solutions of linear sys...