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941.
942.
Meiqiang Feng Xuemei Zhang Weigao Ge 《Journal of Mathematical Analysis and Applications》2008,338(2):784-792
In this paper, exact number of solutions are obtained for the one-dimensional p-Laplacian in a class of two-point boundary value problems. The interesting point is that the nonlinearity f is general form: f(u)=λg(u)+h(u). Meanwhile, some properties of the solutions are given in details. The arguments are based upon a quadrature method. 相似文献
943.
N. R. Sadykov 《Theoretical and Mathematical Physics》2009,158(1):105-111
We show that the optical Magnus effect for dissipative solitons is determined not only by the helicity but also by the topological
index, i.e., by the magnetic quantum number or by the projection of the soliton orbital moment on its trajectory. In the case
of inhomogeneous media, we find a relation between the optical Magnus effect and the nonholonomy of the field of unit vectors
tangent to the trajectory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 158, No. 1, pp. 126–134, January, 2009. 相似文献
944.
For integers m, k≥1, we investigate the maximum size of a directed cut in directed graphs in which there are m edges and each vertex has either indegree at most k or outdegree at most k. © 2009 Wiley Periodicals, Inc. J Graph Theory 相似文献
945.
Kiyoshi Ando 《Journal of Graph Theory》2009,60(2):99-129
An edge of a 5‐connected graph is said to be contractible if the contraction of the edge results in a 5‐connected graph. Let x be a vertex of a 5‐connected graph. We prove that if there are no contractible edges whose distance from x is two or less, then either there are two triangles with x in common each of which has a distinct degree five vertex other than x, or there is a specified structure called a K4?‐configuration with center x. As a corollary, we show that if a 5‐connected graph on n vertices has no contractible edges, then it has 2n/5 vertices of degree 5. © 2008 Wiley Periodicals, Inc. J Graph Theory 60: 99–129, 2009 相似文献
946.
A. A. Abramov V. I. Ul’yanova L. F. Yukhno 《Computational Mathematics and Mathematical Physics》2009,49(3):474-481
The index of the homogeneous self-adjoint boundary value problem for the Hamiltonian systems of ordinary differential equations is introduced. It is assumed that the system has a nontrivial solution. The relationship between the index of an eigenvalue of the nonlinear eigenvalue problem and the index of the corresponding homogeneous problem is established. Properties of the index of the problem and those of the eigenvalue are examined. 相似文献
947.
Bruce Reed 《Discrete Applied Mathematics》2008,156(7):1150-1156
We discuss some new and old results about skew partitions in perfect graphs. 相似文献
948.
L.Yu. Kolotilina 《Linear algebra and its applications》2008,429(10):2521-2539
The paper considers the sharpness problem for certain two-sided bounds for the Perron root of an irreducible nonnegative matrix. The results obtained are applied to prove the sharpness of the related eigenvalue inclusion sets in classes of matrices with fixed diagonal entries, bounded above deleted absolute row sums, and a partly specified irreducible sparsity pattern. 相似文献
949.
In this paper,we show that for a locally LEW-embedded 3-connected graph G in orientable surface,the following results hold:1) Each of such embeddings is minimum genus embedding;2) The facial cycles are precisely the induced nonseparating cycles which implies the uniqueness of such embeddings;3) Every overlap graph O(G,C) is a bipartite graph and G has only one C-bridge H such that CUH is nonplanar provided C is a contractible cycle shorter than every noncontractible cycle containing an edge of C.This ext... 相似文献
950.
Tutte’s 3-Flow Conjecture suggests that every bridgeless graph with no 3-edge-cut can have its edges directed and labelled
by the numbers 1 or 2 in such a way that at each vertex the sum of incoming values equals the sum of outgoing values. In this
paper we show that Tutte’s 3-Flow Conjecture is true for Cayley graphs of groups whose Sylow 2-subgroup is a direct factor
of the group; in particular, it is true for Cayley graphs of nilpotent groups. This improves a recent result of Potočnik et al.
(Discrete Math. 297:119–127, 2005) concerning nowhere-zero 3-flows in abelian Cayley graphs. 相似文献