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1.
若有向图T满足条件:uv(≠)A(T)使得dT (u) dr-(v)≥k,则称图T满足O(k)条件.讨论了有向图及特殊有向图的最长圈,并且给出了某些特殊竞赛图的Hamilton圈的存在条件.  相似文献   

2.
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   

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.
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   

5.
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   

6.
一个双色有向图D(A,B)是本原的,如果存在非负整数h和k,且h+k>0,使得D(A,B)中的母一对顶点(i,j)都存在从i到j的(h,k)途径,且称h+k的最小值为D(A,B)的本原指数.考虑一类特殊的双色有向图,它的未着色图有n个顶点,包含有一个n-圈,n-1/2个2-圈和n个环,给出了本原条件和指数上界.  相似文献   

7.
双极单值中智竞争图是模糊有向图的竞争图的推广.2018年Akram、Nasir和Shum介绍了m-步双极单值中智竞争图.介绍(i,k)-步双极单值中智有向图和竞争图的概念,给出(i,k)-步双极单值中智竞争图的边是独立强的一个条件,证明对双极单值中智有向图D,它的(i,k)-步双极单值中智有向图的竞争图与它的(i,k)...  相似文献   

8.
一类特殊的三色有向图的本原指数   总被引:1,自引:0,他引:1  
一个三色有向图D是本原的,当且仅当存在非负整数h,k,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.文章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3-圈和一个4-圈,我们研究了该图的本原性并给出了在一种本原条件下的三色有向图的本原指数.  相似文献   

9.
为了更进一步了解本原不可幂定号有向图的local基的相关性质,对一类含有3个圈的特殊的本原不可幂定号有向图的第k个local基进行了研究.首先利用相关文献所提及的关于本原不可幂定号有向图的重要定义及其引理,确定出了此类本原不可幂定号有向图的本原指数.由于本图的特殊性,又对其各个圈的圈长及符号分情况进行了讨论,最后得到了这类本原不可幂定号有向图的第k个local基.主要运用"异圈对"、Frobenius集和本原指数等相关知识,以及反证法,详细地分析了这类图的第k个local基.  相似文献   

10.
为了进一步了解本原不可幂定号有向图的k重上广义基的相关性质,本文对一类特殊的含有三个圈的k本原不可幂定号有向图的k重上广义基进行了研究,这类图中存在两个长度相同的圈.运用"异圈对"、 Frobenius集以及本原指数等相关知识,分别讨论了在这类图中长度相同的两个圈的同号或异号的情况下,是否存在相应的SSSD途径对,从而获得了这类本原不可幂定号有向图在这两种情况下的k重上广义基的界及相关性质.  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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