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排序方式: 共有462条查询结果,搜索用时 15 毫秒
31.
V.V. Mkrtchyan 《Discrete Mathematics》2006,306(4):456-459
I prove that in a tree in which the distance between any two endpoints is even, there is a maximum proper partial 0-1 coloring such that the edges colored by 0 form a maximum matching. 相似文献
32.
In our previous work, we have given an algorithm for segmenting a simplex in the n-dimensional space into rt n+ 1 polyhedrons and provided map F which maps the n-dimensional unit cube to these polyhedrons. In this paper, we prove that the map F is a one to one correspondence at least in lower dimensional spaces (n _〈 3). Moreover, we propose the approximating subdivision and the interpolatory subdivision schemes and the estimation of computational complexity for triangular Bézier patches on a 2-dimensional space. Finally, we compare our schemes with Goldman's in computational complexity and speed. 相似文献
33.
We obtain exact lower bounds of the upper limits of ratios of the Nevanlinna characteristics of a delta-subharmonic function in the upper half-plane. 相似文献
34.
Separation theorems for an arbitrary set and a not necessarily convex set in a linear topological space are proved and applied to vector optimization. Scalarization results for weakly efficient points and properly efficient points are deduced. 相似文献
35.
C.Fefferman定理证明了光滑有界强拟凸域之间的双全纯映射可以光滑延拓到边界,这个结果已经被推广到各种情形.其中Bell和Catlin以及Diederich和Fornaess独立地将其推广到拟凸域的逆紧全纯映射.本文较全面地综述了C.Fefferman定理的推广情况以及Bergman投射的边界正则性问题,同时对如何去掉Bell和Catlin以及Diederich和Fornaess定理条件中的拟凸性给出一个新观察,提出一个解决方向并且说明在具体情况下这个新观察确实是可以提供答案的. 相似文献
36.
Kun Li Ting-Zhu Huang Liang Li Stéphane Lanteri 《Numerical Methods for Partial Differential Equations》2023,39(2):932-954
In this artice, we report on a reduced-order model (ROM) based on the proper orthogonal decomposition (POD) technique for the system of 3-D time-domain Maxwell's equations coupled to a Drude dispersion model, which is employed to describe the interaction of light with nanometer scale metallic structures. By using the singular value decomposition (SVD) method, the POD basis vectors are extracted offline from the snapshots produced by a high order discontinuous Galerkin time-domain (DGTD) solver. With a Galerkin projection and a second order leap-frog (LF2) time discretization, a discrete ROM is constructed. The stability condition of the ROM is then analyzed. In particular, when the boundary is a perfect electric conductor condition, the global energy of the ROM is bounded, which is consistent with the characteristics of global energy in the DGTD method. It is shown that the ROM based on Galerkin projection can maintain the stability characteristics of the original high dimensional model. Numerical experiments are presented to verify the accuracy, demonstrate the capabilities of the POD-based ROM and assess its efficiency for 3-D nanophotonic problems. 相似文献
37.
设f:V(G)∪E(G)→{1,2,…,k}是图G的一个正常k-全染色。令■其中N(x)={y∈V(G)|xy∈E(G)}。对任意的边uv∈E(C),若有Φ(u)≠Φ(v)成立,则称f是图G的一个邻点全和可区别k-全染色。图G的邻点全和可区别全染色中最小的颜色数k叫做G的邻点全和可区别全色数,记为f tndi∑(G)。本文确定了路、圈、星、轮、完全二部图、完全图以及树的邻点全和可区别全色数,同时猜想:简单图G(≠K2)的邻点全和可区别全色数不超过△(G)+2。 相似文献
38.
J. M. Soriano 《应用数学和力学(英文版)》2006,27(9):1265-1274
Sufficient conditions were given to assert that between any two Banach spaces over K, Fredholm mappings share at least one value in a specific open ball. The proof of the result is constructive and based upon continuation methods. 相似文献
39.
In Bayesian analysis, the Markov Chain Monte Carlo (MCMC)
algorithm is an efficient and simple method to compute posteriors. However, the
chain may appear to converge while the posterior is improper, which will leads
to incorrect statistical inferences. In this paper, we focus on the necessary and
sufficient conditions for which improper hierarchical priors can yield proper
posteriors in a multivariate linear model. In addition, we carry out a simulation
study to illustrate the theoretical results, in which the Gibbs sampling and
Metropolis-Hasting sampling are employed to generate the posteriors. 相似文献
40.
John Engbers 《Journal of Graph Theory》2017,85(4):780-787
For graphs G and H , an H‐coloring of G is a map from the vertices of G to the vertices of H that preserves edge adjacency. We consider the following extremal enumerative question: for a given H , which connected n‐vertex graph with minimum degree δ maximizes the number of H‐colorings? We show that for nonregular H and sufficiently large n , the complete bipartite graph is the unique maximizer. As a corollary, for nonregular H and sufficiently large n the graph is the unique k‐connected graph that maximizes the number of H‐colorings among all k‐connected graphs. Finally, we show that this conclusion does not hold for all regular H by exhibiting a connected n‐vertex graph with minimum degree δ that has more ‐colorings (for sufficiently large q and n ) than . 相似文献