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1.
整数距离图G(D)以全体整数为顶点集,顶点u,v相邻当且仅当|u-v|∈D,其中D是一个正整数集。对于m≥4k,k≥3,设Dm,k,3={1,2,…,m}\{k,2k,3k},得到了G(Dm,k,3)的点荫度的上界和下界并决定了它在某些m上的确切值。  相似文献   

2.
整数距离图G(D)以全体整数为顶点集,顶点u,v相邻当且仅当|u—v|∈D,其中D是一个正整数集.对于m〉3,设Dm,3={1,2,…m}\{3},得到了G(Dm,3)的点荫度的上界和下界并决定出了它在某些m上的确切值.  相似文献   

3.
整数距离图G(Dm,2)的点线性荫度   总被引:1,自引:1,他引:1  
整数距离图G(D)以全体整数为顶点集,顶点u,v相邻当且仅当|u-t|∈D,其中D是一个正整数集.对于m≥11,设Dm.2={1,2,…,m}\{2},得到了G(Dm,2)的点线性荫度的上界和下界并决定出了它在某些特殊的m上的确切值.  相似文献   

4.
整数距离图以全体整数作为顶点集,顶点u、υ相邻当且仅当|u-υ|∈D,其中D是一个正整数集.对于m〉3,令Dm=[1,m]/[1,3].本研究得到了G(Dm)的点荫度.  相似文献   

5.
距离图的点荫度   总被引:1,自引:2,他引:1  
实数距离图G(R,D)是顶点集为实数轴上的所有点,顶点u,v∈R相邻当且仅当|u-v|∈D,其中D是一个正实数集.讨论了当D为1到δ的区间时,实数距离图G(R,D)的点荫度.特别地,当3D是某正整数集合,Z是整数集时,得出了整数距离图G(Z,D)的点荫度的几个上界.  相似文献   

6.
图G的一个L(2,1)标号就是从顶点集V(G)到非负整数集的一个函数f,使得d(u,v)=1时,有|f(u)-f(v)| ≥2;当d(u,v)=2时,有|f(u)-f(v)|≥1,其中u,v是图G的顶点.不妨设最小标号为.那么,图G的L(2,1)-标号数λ(G)是G的所有L(2,1)标号下的跨度max {f(v);v∈V(G)}的最小数.本文定义了拟m(o)bius梯子,并完全确定了拟m(o)bius梯子的L(2,1)标号数.  相似文献   

7.
利用整数距离图的结构特征,研究当m<2k时,G(Z,Dm,k,t)的分数色数(其中Dm,k,t={1,2,…,m}-{k,k+1,…,k+t}),并给出在k>t,m≥2k条件下G(Z,Dm,k,t)的分数色数,以及当k>t,m=2k+i,0≤i≤2t-1时,G(Z,Dm,k,t)的色数.  相似文献   

8.
图G的一个L(2,1)标号就是从顶点集V(G)到非负整数集的一个函数f,使得d(u,v)=1时,有|f(u)-f(v)|≥2;当d(u,v)=2时,有|f(u)-f(v)|≥1,其中u,v是图G的顶点.不妨设最小标号为.那么,图G的L(2,1)-标号数λ(G)是G的所有L(2,1)标号下的跨度max{f(v);v∈V(G)}的最小数.本文定义了拟mbius梯子,并完全确定了拟mbius梯子的L(2,1)标号数.  相似文献   

9.
图G的L(2,1)-标号是从图G的顶点集到非负整数集的一个映射f∶V(G)→{0,1,2,…},它满足对任意两个顶点x,y,当d(x,y)=1时,|f(x)-f(y)|≥2;当d(x,y)≥2时,|f(x)-f(y)≥1.研究了n≡0(mod3)的广义Petersen图G=P(n,t)的L(2,1)-标号数λ2,1(G),得到当t=0(mod3),5≤λ2,1(G)≤8,否则λ2,1(G)=5  相似文献   

10.
设p,q为两个非负整数,一个图G的L(p,q)-标号是一个从G的顶点集V(G)到一个非负整数集的映射f,使得对于G中的任意两个顶点u,v,当d(u,v)=1时,|f(u)-f(v)|≥p;当d(u,v)=2时,|f(u)-f(v)|≥q;根据p,q之间的关系,给出两个顶点数都是n的完全图的匹配和的L(p,q)-标号数的上界.而当q≤p≤2q时,确定了两个顶点数都是n的完全图的匹配和的L(p,q)-标号数的准确值.  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.
<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   

20.
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