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1.
若有向图T满足条件:uv (∈)A(T)且存在一点w使得uw ∈A(T),wv∈A(T)则d-(u)+d+(v)≥n,称图T满足G(n)条件.在本文中,我们讨论了如果T(p,q)二部竞赛图满足G(n)条件且强连通,则T(p,q)包含一条长至少为2min{n+1,p,q}的圈,除非n为偶数且T(p,q)同构于一类图族B(k1,k2,k3,n/2),k1≥n/2,i=1,2,3,及特殊竞赛图的最长圈问题.  相似文献   

2.
若有向图T满足条件:uv■A(T)使得d T(u) dT-(v)≥k,则称图T满足O(k)条件.在该文中,笔者讨论了竞赛图的最长圈,并且给出了某些有向图的Hamilton圈的存在条件.  相似文献   

3.
用图论的方法讨论有向图Δ的几何性质及其路代数k(Δ)的代数性质.论图Δ不是有向环线弧点图,则Δ是双侧连接图■k(Δ)是素代数,给出了无限和有限竞赛图Hamilton圈存在的路代数条件;给出了半素路代数的有向图特征.  相似文献   

4.
利用图的邻接矩阵与一种特殊矩阵置换相似的关系判别图中Hamilton圈(路)的存在情况。首先对于不完全图的无向图和有向图进行分析,给出不完全图和完全图存在Hamilton圈(路)的充分必要条件,然后得出了竞赛图寻找Hamilton圈(路)的简单方法。  相似文献   

5.
有向图中最长路或圈   总被引:1,自引:0,他引:1  
本文讨论了有向图中最长路或圈和二部竞赛图的Hamilton圈,得到关于点的次的几个充分条件,在某种意义上说,这些条件是最好的可能。  相似文献   

6.
针对圆有向图的(1,2)步竞争图的结构,提出了竞争图中是否存在哈密尔顿圈;通过特殊到一般的方法得到如下结论:对于阶数n(n≥5)的强连通圆有向图的(1,2)步竞争图中存在哈密尔顿圈,而其余情形的圆有向图的(1,2)步竞争图中则不存在哈密尔顿圈。  相似文献   

7.
一个双色有向图D是本原的,当且仅当存在非负整数h,k,且h+k0,使得D的每一对顶点(i,j)都存在从i到j的(h,k)-途径,称h+k的最小值为D的本原指数.文章研究了一类特殊的双色有向图,其未着色图含有n个2-圈和2个m-圈,对其着色进行了分类,研究了所给类的本原性,并给出了本原指数的上界.  相似文献   

8.
一个三色有向图D是本原的,当且仅当存在非负整数h、k和l,且h+k+l>0,使得D中的每一对顶点(i,j)都存在从i到j的(h,k,l)-途径,并称h+k+l的最小值为D的本原指数.对一类特殊的三色有向图进行了研究,其未着色图恰含一个n-圈、一个(n-2)-圆和一个3-圈,给出了一种本原条件下的本原指数,并对其所表达的本析指数进行了极图刻划.  相似文献   

9.
一类恰含三个圈的三色有向图的本原指数   总被引:2,自引:0,他引:2  
一个三色有向图D是本原的,当且仅当存在非负整数h、k和v, 且h+k+v>0,使得D中的每一对顶点(i,j)都存在从i到j的(h,k,v)途径, 称h+k+v的最小值为D的本原指数。 本文研究一类特殊的三色有向图,其未着色图恰含一个n-圈、一个(n-1)-圈和一个2-圈, 给出了本原条件和本原指数上界, 并对本原指数上界的极图进行了刻划。  相似文献   

10.
设G是一个n阶图,若对于每一个k (3≤k≤n),图G都含有k-圈,则称图G为泛圈图.泛圈图是圈理论研究中的重要课题.研究得到了Hamilton圈上两个不相邻的点在圈上的距离是3的泛圈性结果.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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