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1.
《Discrete Mathematics》2020,343(2):111679
A path in an edge-colored graph is called monochromatic if any two edges on the path have the same color. For , an edge-colored graph is said to be monochromatic -edge-connected if every two distinct vertices of are connected by at least edge-disjoint monochromatic paths, and is said to be uniformly monochromatic -edge-connected if every two distinct vertices are connected by at least edge-disjoint monochromatic paths such that all edges of these paths are colored with a same color. We use and to denote the maximum number of colors that ensures to be monochromatic -edge-connected and, respectively, to be uniformly monochromatic -edge-connected. In this paper, we first conjecture that for any -edge-connected graph , , where is a minimum -edge-connected spanning subgraph of . We verify the conjecture for . We also prove the conjecture for and with . When is a minimal -edge-connected graph, we give an upper bound of , i.e., . For the uniformly monochromatic -edge-connectivity, we prove that for all , , where is a minimum -edge-connected spanning subgraph of . 相似文献
2.
Paul S. Wesson 《General Relativity and Gravitation》2003,35(1):111-119
Results from 5D induced-matter and membrane theory with null paths are extended to show that a particle obeys the 4D Klein-Gordon equation but with a variable mass. The Dirac equation also follows, but raises concerns about 4D quantization in the two natural 5D gauges, and reopens the question of a Regge-like trajectory for the spin angular momenta and squared masses of gravitationally-dominated systems. 相似文献
3.
Regis Guyonnet 《Journal of statistical physics》1991,65(1-2):269-289
The NMR properties of nuclei linked to long linear polymer molecules are sensitive to the influence of hard walls. In this context, the residual energy of tensorial spin-spin interactions is calculated using a path integral approach. Several thermodynamic quantities of the polymer system (free energy, equation of state,...) are also expressed, taking chain stiffness effects and the presence of two repulsive walls into consideration. 相似文献
4.
M. Gorkunov M. Lapine E. Shamonina K.H. Ringhofer 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(3):263-269
Effective magnetic properties of a composite meta-material consisting of periodically arranged circular conductive elements
are studied theoretically. A general expression for the effective bulk permeability is obtained with mutual effects and lattice
ordering being taken into account. The resonance frequency of the permeability is found to be strongly dependent on the size
and shape of the unit cell. Frequency dispersion of the permeability is studied with special attention paid to the frequency
range, where negative values of the permeability are possible. Corresponding recommendations for optimisation of the meta-materials
with negative permeability are made. The results are confirmed by numerical simulations of the finite structure behaviour
in an external magnetic field.
Received 19 April 2002 Published online 31 July 2002 相似文献
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Let G=(V(G),E(G)) be a graph. A (n,G, λ)‐GD is a partition of the edges of λKn into subgraphs (G‐blocks), each of which is isomorphic to G. The (n,G,λ)‐GD is named as graph design for G or G‐decomposition. The large set of (n,G,λ)‐GD is denoted by (n,G,λ)‐LGD. In this work, we obtain the existence spectrum of (n,P3,λ)‐LGD. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 151–159, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10008 相似文献
7.
Lance Nielsen 《Acta Appl Math》2002,74(3):265-292
Stability properties of Feynman's operational calculus are addressed in the setting of exponential functions of noncommuting operators. Applications of some of the stability results are presented. In particular, the time-dependent perturbation theory of nonrelativistic quantum mechanics is presented in the setting of the operational calculus and application of the stability results of this paper to the perturbation theory are discussed. 相似文献
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A Dirac picture perturbation theory is developed for the time evolution operator in classical dynamics in the spirit of the Schwinger–Feynman–Dyson perturbation expansion and detailed rules are derived for computations. Complexification formalisms are given for the time evolution operator suitable for phase space analyses, and then extended to a two-dimensional setting for a study of the geometrical Berry phase as an example. Finally a direct integration of Hamilton's equations is shown to lead naturally to a path integral expression, as a resolution of the identity, as applied to arbitrary functions of generalized coordinates and momenta. 相似文献
10.