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181.
图的染色问题在组合优化、计算机科学和Hessians矩阵的网络计算等方面具有非常重要的应用。其中图的染色中有一种重要的染色——线性荫度,它是一种非正常的边染色,即在简单无向图中,它的边可以分割成线性森林的最小数量。研究最大度$\bigtriangleup(G)\geq7$的平面图$G$的线性荫度,证明了对于两个固定的整数$i$,$j\in\{5,6,7\}$,如果图$G$中不存在相邻的含弦$i$,$j$-圈,则图$G$的线性荫度为$\lceil\frac\bigtriangleup2\rceil$。 相似文献
182.
Wang Yongqian Liao Xianbo Diao Hongwei Cheng Wenchao Li Guohua Chen Changyong Zhang Shibin Xu Yanyue Chen Weide Kong Guanglin 《中国科学A辑(英文版)》2002,45(10):1320-1328
A set of a-SiOx:H (0.52 <x< 1.58) films are fabricated by plasma-enhanced-chemical-vapor-deposition (PECVD) method at the substrate temperature
of 250°C. The microstructure and local bonding configurations of the films are investigated in detail using micro-Raman scattering,
X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It is found that the films are
structural inhomogeneous, with five phases of Si, Si2O:H, SiO:H, Si2O3:H and SiO2 that coexist. The phase of Si is composed of nonhydrogenated amorphous silicon (a-Si) clusters that are spatially isolated.
The average size of the clusters decreases with the increasing oxygen concentration x in the films. The results indicate that
the structure of the present films can be described by a multi-shell model, which suggests that a-Si cluster is surrounded
in turn by the subshells of Si2O:H, SiO:H, Si2O3:H, and SiO2. 相似文献
183.
Yuan Lou 《Journal of Nonlinear Modeling and Analysis》2019,1(2):151-166
In this paper, the formats of Julia sets for a class of nonlinear complex dynamic systems with variable coefficients were studied under certain conditions. For the complex dynamic systems in piecewise cases, we proposed some methods to control the forms of their Julia sets and stable domains analytically. What’s more, we illustrated that our methods worked well by computational simulations. Our work provides a better understanding about how to control the Julia sets of certain complex dynamic systems. 相似文献
184.
Hai Q. Dinh Xiaoqiang Wang Hongwei Liu Songsak Sriboonchitta 《Discrete Mathematics》2019,342(5):1456-1470
Let be an odd prime, , be positive integers, be nonzero elements of the finite field such that . In this paper, we show that, for any positive integer , the Hamming distances of all repeated-root -constacyclic codes of length can be determined by those of certain simple-root -constacyclic codes of length . Using this result, Hamming distances of all constacyclic codes of length are obtained. As an application, we identify all MDS -constacyclic codes of length . 相似文献
185.
Amin Esfahani Luiz Gustavo Farah Hongwei Wang 《Nonlinear Analysis: Theory, Methods & Applications》2012
In this paper we prove local well-posedness in L2(R) and H1(R) for the generalized sixth-order Boussinesq equation utt=uxx+βuxxxx+uxxxxxx+(|u|αu)xx. Our proof relies in the oscillatory integrals estimates introduced by Kenig et al. (1991) [14]. We also show that, under suitable conditions, a global solution for the initial value problem exists. In addition, we derive the sufficient conditions for the blow-up of the solution to the problem. 相似文献
186.
187.
Improving Construction for Connected Dominating Set with Steiner Tree in Wireless Sensor Networks 总被引:2,自引:0,他引:2
Manki Min Hongwei Du Xiaohua Jia Christina Xiao Huang Scott C.-H. Huang Weili Wu 《Journal of Global Optimization》2006,35(1):111-119
The connected dominating set plays an important role in ad hoc wireless networking. Many constructions for approximating the minimum connected dominating set have been proposed in the
literature. In this paper, we propose a new one with Steiner tree, which produces approximation solution within a factor of
6.8 from optimal. This approximation algorithm can also be implemented distributedly. 相似文献
188.
用群状结构法研究拟线性热方程的分离变量解,对于允许和型分离变量解的二阶拟线性热方程给出了一个完整的分类.说明了一些带有函数类型反应项的方程具有函数分离变量解,推广了前人的结论. 相似文献
189.
190.
In this paper, we study the consistency of the regularized least-square regression in a general reproducing kernel Hilbert space. We characterize the compactness of the inclusion map from a reproducing kernel Hilbert space to the space of continuous functions and show that the capacity-based analysis by uniform covering numbers may fail in a very general setting. We prove the consistency and compute the learning rate by means of integral operator techniques. To this end, we study the properties of the integral operator. The analysis reveals that the essence of this approach is the isomorphism of the square root operator. 相似文献