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1.
图G的染色数X(G)是使得G中任何相邻两点均染不同色的最小颜色数。文中证明了,如果ω(G)≥6,△(G)=ω(G)+1,ㄧV(G)ㄧ≤2ω(G)+1,则X(G)=ω(G),给出了两个图G0,G1,使得ㄧV(G0)ㄧ=14,ω(G0)=6,△(G0)=7,X(G0)=7;ㄧV(G1)ㄧ=11,ω(G1)=5,△(G1)=6,X(G1)=6。  相似文献   

2.
图G的全色数XT(G)是使得V(G)U∪E(G)中相邻或相关联的元素均染不同颜色的最少颜色数目.如果XT(G)=△(G)+1,则记如果XT(G)=△(G)+2,则记G∈.两个图G和H的联图G∨H是一个简单图,使得V(G∨H)=V(G)∪V(H),E(G∨H)=E(G)∪E(H)∪{uv(G),v∈(H)}.本文证明了对任意的两个正整数m和n,Pm∨Pn∈当且仅当m=n=2或m=n=1,从而完全确定了两个路的联图的全色数.  相似文献   

3.
图G的全色数XT(G)是使得V(G)∪E(G)中相邻或相关的元素均染不同颜色的最少颜色数目。如果XT(G)=△(G)+1,则记G∈C1/T;如果XT(G)=△(G)+2,则记G∈C2/T。  相似文献   

4.
点泛圈偶图   总被引:1,自引:0,他引:1  
设G是连通偶图,(X1,X2)是其顶点的二分类,|X1|=|X2|=n,δ(G)≥t≥3,且对于Xi中的任意两点u和v,均有|N(u)∪N(v)|≥n-(t-2),i=1,2,文中对t≤6的情况,证明G是点泛圈偶图。  相似文献   

5.
设G是n阶1-坚韧图,X是G的顶点子集合,定义α(X)=max{|S||S是诱导子图G[X]中的顶点独立集},σk(X)=min{ki=1d(xi)|{x1,x2,…,xk}是独立集}和c(X)=max{|V(C)∩X||C是G中的圈}。我们得到如下主要结果:设G是n阶1-坚韧图,并且σ3(X)≥n,则c(X)≥min{|X|,|X|+δ(X)-α(X)+1|,并且这下界是最好的,这里δ(X)是不小于13σ3(X)的最小正整数.  相似文献   

6.
相同维数的非线性不可约特征标很少的有限群   总被引:1,自引:1,他引:0  
证明了当k≥2时,G为Dk群当且仅当G=H|×G′是以素数幂阶群G′为核的,以循环群H为补的Frobenius群,且G有含在G′中的一段主群列1=QsQs-1Q1=G″Q0=G′,使Qi/Qi+1=Z(G′/Qi+1),Qi/Qi+1=qr=G′/G″,对每g∈Qi-Qi+1,|CG′(g)|=|G′/Qi+1|=q(i+1)r,i=0,1,,s-1.且有k|H|+s|H|=s(qr-1).  相似文献   

7.
图的正交因子分解   总被引:1,自引:0,他引:1  
研究了图的正交因子分解问题.设k1,…,km是正整数,G是[0,k1+…+km-m+1]-图,H是G的任一有m条边的子图.若|V(H)|≥|E(H)|=m,则图G有一个[0,ki]m1-因子分解与H正交  相似文献   

8.
设G是连通偶图,(X1,X2)是其顶点的二分类,|X1|=|X2|=n,δ(G)≥t≥3。证明了若任意u,v∈Xi蕴含|N(u)∪N(v)|≥n-(t-2),i=1,2,则当t=7时G是点泛圈偶图。  相似文献   

9.
研究了最大度顶点互不相邻的高度图的全色数.得到:设图G的最大度顶点是互不相邻的,且δ(G)≥34|V(G)|,则xT(G)=Δ(G)+1  相似文献   

10.
图G的全色数XT(G)是使得V(C)UE(C)中相邻或相关联元素均着不同色的最少色数.若G的最大次点不相邻,△(G)=3,则XT(G)=4.  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.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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