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481.
482.
Haim Harari 《Nuclear Physics B》1979,161(1):55-60
Simple assumptions which have little or no connection to quantum chromodynamics, lead to upper and lower bounds for the slope of the graph for log MN′ versus log MN, where MN is the Nth moment of the deep inelastic structure function xF3(x, q2). The published results of the CDHS and BEBC collaborations cover the entire range allowed by our bounds and therefore cannot be considered as evidence for the validity of QCD. 相似文献
483.
The first observation of interference effects between two sharp resonant contributions to the third-order nonlinear susceptibility χ(3) (ω3=ω0+ω1?ω2) is reported. Using two tunable near ir frequencies, ω0=ω1 and ω2, the was seen in crystalline CuCl when 2ω1 and ω1?ω2 were close to the sharp Z3 exciton at 3.21 eV and the 210 cm-1 Raman line, respectively. Three different tunable visible frequencies were used to observe similar interference effects in a benzene-cyclohexane mixture when ω0?ω2 and ω1?ω2 were close to the 992 cm-1 Raman line of benzene and the 801 cm-1 Raman line of cyclohexane, respectively. 相似文献
484.
This article is concerned with the partial regularity of the weak solutions satisfying energy inequality and monotonicity inequality to the initial-boundary value problem of Landau–Lifshitz system of ferromagnetic spin chain with Gilbert damping in higher dimensions. A generalized monotonicity inequality is derived. The singular set and its Hausdorff dimension are discussed. 相似文献
485.
In this article, we give a uniform BV estimates and L 1-stability of solutions to the Lax–Friedrichs' scheme for a model of radiating gas when the strict C–F–L (Courant–Friedrichs–Levy) condition is satisfied. This result implies that the approximate solutions generated by the Lax–Friedrichs' scheme converge to the solution given by the method of vanishing viscosity [C. Lattanzio and P. Marcati (2003). Global well-posedness and relaxation limits of a model for radiating gas. Journal of Differential Equations, 190, 439–465]. 相似文献
486.
The harmonic problem in a cracked domain is studied in R m , m?>?2. The boundary of the domain is assumed to be nonsmooth, while cracks are smooth. The Dirichlet condition is specified on the boundary of the domain. Jumps of the unknown function and its normal derivative are specified on the cracks. Uniqueness and solvability results are obtained. The problem is reduced to the uniquely solvable integral equation, its solution is given explicitely in the form of a series. The estimates of the solution of the problem depending on the boundary data are obtained. 相似文献
487.
A mathematical model for frictionless contact of a deformable body with a rigid moving obstacle is analyzed. The Prandtl–Reuss elastic-perfectly-plastic constitutive law is used to describe the material's behavior, and contact is modeled with a unilateral condition imposed on the surface velocity. The problem is motivated by the process of the plowing of the ground. A variational formulation of the problem is derived in terms of the stresses and the existence of the unique weak solution is proven. The proof is based on arguments for differential inclusions obtained in A. Amassad, M. Shillor and M. Sofonea (2001). A quasistatic contact problem for an elastic perfectly plastic body with Tresca's friction. Nonlin. Anal., 35, 95–109. Finally, a study of the continuous dependence of the solution on the data is presented. 相似文献
488.
O.D. Anderson† 《International Journal of Mathematical Education in Science & Technology》2013,44(4):482-484
A discussion lesson for a sixth‐form statistics group is presented, and this article is intended as a pointer to a more acceptable approach for that level of student. A major objective in school instruction should be to develop numeracy, which includes a critical appraisal of all quantitative claims made to citizens in everyday living. Here we consider the case of a typical (though hypothetical) television commercial; and, apart from questioning its immediate message, indicate the sort of thoughts that it might profitably spark off. 相似文献
489.
This article studies some geometrical aspects of the semidefinite linear complementarity problem (SDLCP), which can be viewed as a generalization of the well-known linear complementarity problem (LCP). SDLCP is a special case of a complementarity problem over a closed convex cone, where the cone considered is the closed convex cone of positive semidefinite matrices. It arises naturally in the unified formulation of a pair of primal-dual semidefinite programming problems. In this article, we introduce the notion of complementary cones in the semidefinite setting using the faces of the cone of positive semidefinite matrices and show that unlike complementary cones induced by an LCP, semidefinite complementary cones need not be closed. However, under R 0-property of the linear transformation, closedness of all the semidefinite complementary cones induced by L is ensured. We also introduce the notion of a principal subtransformation with respect to a face of the cone of positive semidefinite matrices and show that for a self-adjoint linear transformation, strict copositivity is equivalent to strict semimonotonicity of each principal subtransformation. Besides the above, various other solution properties of SDLCP will be interpreted and studied geometrically. 相似文献
490.
The relationship between the finite structure, the infinite structure, and the Wiener–Hopf factorization indices of any rectangular rational matrix is studied. 相似文献