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1.
设n≥3阶1—坚韧图,若对于G中任意导出爪K(1.3)或变爪K(1.3)+e上的三点u,v,w,且d(u,v)=d(u,w)=2,均满足|N(u)∩N(v)|≥-α-1或|N(u)∩N(w)|≥α-1,则G是Hamilton图。  相似文献   

2.
文章给出了λ4-最优图的一个充分条件.设G是阶为n≥11的λ4-连通图,若对G中任意一对不相邻顶点u,v,有|N(u)∩N(v)|≥6且G|N(u)∩N(v)|至少包含16条边,则G是λ4-最优的.  相似文献   

3.
文章给出了满足一定条件的图的λ6-最优性的领域交条件.设图G是连通图,若对G中任意一对不相邻顶点u,v,都有|N(u)∩N(v)|≥10且|X5|≤5,则G是λ6-最优的;若对于连通图G中任意一对不相邻顶点u,v,都有|N(u)∩N(v)|≥10且对图中每个三角形T至少存在一个顶点v∈V(T)使得d(v)≥v2+5,则G是λ6-最优的.  相似文献   

4.
设G是一个图,G的部分平方图G^*满足V(G^*)=V(G),E(G^*)=E(G)∪{uv:uv∈E(G),且J(u,v)≠φ},这里J(u,v)={w∈N(u)∩N(v),N(w)(∈)N[u]∪N[v]}.本文利用插点方法,给出了关于k,或(k+1)-连通(k≥2)图G是哈密尔顿的,1-哈密尔顿的或哈密尔顿连通的统一证明.其充分条件是在图G中关于^k∑i=1|N(Yi)|+b|N(y0)|与n(Y)的不等式,这里Y是图G的部分平方图G^*的任一独立集,对于i∈{1,2,…,k},Yi={yi,yi-1,…,yi-(b-1)}(∈ )Y(yj的下标将取模k);b是一个整数,且0<b<k+1;n(Y)=|{v∈V(G),dist(v,Y)≤2}|.  相似文献   

5.
文章给出了二部图是λ4-最优的一个领域交条件.设n为一个不小于8的正整数,令G=(X∪Y,E)为一个n阶二部图且ξ4(G)≤n/2.若G有一个饱和X或Y中所有顶点的匹配且对任意的u,v∈X和u,v∈Y都有|N(u)∩N(v)|≥4,则G是λ4-最优的.  相似文献   

6.
文章给出了图的λ4-最优性的邻域交条件.设图G是阶至少为34的λ4-连通图,若对G中任意一对不相邻顶点u,v,都有|N(u)∩N(v)|≥6且ξ4(G)≤3n(G)/2+3,则G是λ4-最优的;若对于λ4-连通图G中任意一对不相邻顶点u,v,都有|N(u)∩N(v)|≥6且对图中每个三角形T至少存在一个顶点v∈V(T)...  相似文献   

7.
证明了如下结论:设G是p阶连通图,其中p≡n(mod2)且n<p,如果对满足条件d(u,v)=2的任意点集{u,v}包含于V(G),有d(u) d(v)≥p n-1,则G是n-因子-临界图。  相似文献   

8.
在文[1]中给出定理,设G是一个n-阶2-连通图且δ(G)≥t,若对于G的任意两个不相邻的点u和v,均有|N(u)∪N(v)|≥n-t成立,则G是一个泛圈图或G≌Kn/2,n/2.本文的目的在于将此定理的条件减弱,只对图中距离为2的点进行讨论,得出了泛圈图的一个充分条件.文中主要用数学归纳法对定理进行证明,先在引理中给出了几种特殊情况的证明,接着在定理的证明中讨论了一般情形.  相似文献   

9.
Let G be a graph of order n.For graph to be Hamiltonian,beginning with Dirac’s classic result in 1952,Dirac’s theorem was followed by that of Ore in1960.In1984,Fan generalized Dirac’s theorem and Ore’s theorem as if G is a2-connected graph of order n and max{d(u),d(v)}≥n/2for each pair of vertices u and v with d(u,v)=2,then G is hamiltonian.In1991,Faudree et al proved that if G is a2-connected graph and,| N(u)∪N(v)|+δ(G)≥n for each pair of nonadjacent vertices u,v∈V(G),then G is hamiltonian.This paper generalizes the above onditions of Dirac,Ore,Fan and Faudree et al in the case of3-connected graph and proves that if G is a3-connected graph of order n and max{|N(x)∪ N(y)|+d(u),|N(w)∪N(z)|+d(v)}≥n for every choice of6Essential independent vertices,then G is hamiltonian.  相似文献   

10.
证明如下结果:G是简单图满足条件:对G中任一对不相邻顶点u、v有max{d(u),d(v)} |N(u)∪N(v)|≥n-1;且对任意T包含V(G),有ω(G\)≤|T|,则G是Hamilton图。  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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