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1.
双外平面图是一个平面图,它可以嵌入到平面上并使得它的顶点出现在两个面的边界上.设G是一个双外平面图,V(G)、E(G)、F(G)分别为双外平面图G的点集、边集和面集.G的全色数XT,(G)是使得V(G)∪E(G)中的任意相邻或相关联的两个元素均染不同颜色的最少颜色数.本文证明了最大度至少是6的2连通的特殊双外平面图G的全色数是△(G) 1,其中△(G)为G的最大度数.  相似文献   

2.
Halin-图是3-连通平面图,且存在一个面,删除关联于该面的边后是一棵树,图的列表染色是任给图G的每个顶点V配一颜色集合L(V),满足|L(V)|=k,k为某确定正数;G的每个点若均可着从L(V)中选出的一种颜色,使得任意两个相邻近的点着不同的色,则称G是k-可选择的,Min(k)称为G的选择数或列表色数,记x_L(G),本文证明了Halin图的列表色数为3或4,并得到了x_L(G)=3的充要条件。  相似文献   

3.
G是一个简单图,G的一个E-全染色f是指使相邻顶点着不同颜色且每条关联边与它的顶点着以不同颜色的全染色。设f为G的一个E-全染色,对任意x∈V(G),用C(x)表示在f下顶点的颜色以及与x关联的边的颜色所构成的集合。若任意u,v∈V(G),u≠v,有C(u)≠C(v),则称f是图G的点可区别的E-全染色,简称VDET染色。图G的VDET染色所用颜色数目的最小值称为图G的的点可区别E-全色数或简称VDET色数,记为χ_vt~e(G)。讨论并给出了完全二部图K_(4,n)(n≥47)的点可区别E-全色数。  相似文献   

4.
韩淑芹  高洪国 《山东科学》2007,20(1):1-2,18
设G是一个简单图,其顶点集为V(G)而边集为E(G).图G的一个k-染色是指顶点集V(G)到色集{1,2,…,k}的一个映射.如果图G的一个点染色使G的每个极大团所有颜色均出现(这里不要求邻点染色不同),则称该染色为图G的全色极大团染色.而G的全色极大团色数是指能进行全色极大团染色的最大颜色数,记为χmaxcT(G).  相似文献   

5.
一个连通图G的最大亏格γM(G)=(β(G) ξ(G))/2,其中β(G)=|E(G)|-|V(G)| 1称为G的圈秩数,ξ(G)是G的Betti亏数.图G的C-划分是指:G的一个顶点划分{V1,V2,…,Vn},使得每个G[Vi]为多重完全图(1≤i≤n).一个图的2-因子是指G的一个2-正则支撑子图F,若F为图G的一个2-因子.联系图的顶点划分和四边形2-因子的条件,本文给出了新的上可嵌入的图类.  相似文献   

6.
设G是非平凡连通图,记c:V(G)→N是G的一个顶点染色,这里相邻的两个顶点可以着相同的颜色。对于图G的任一顶点ν,与ν相邻的顶点所着颜色的集称为邻色集,记NC(ν)。如果G中任意相邻的两个顶点ν,u满足NC(u)≠NC(ν),则称c是G的一个集合染色。集合染色所需的最少的颜色数称为G的集合色数,记χs(G)。本文给出了团数是3的平面图,没有4圈的平面图及烟花图和风车图的集合色数。  相似文献   

7.
图G的全色数x_T(G)是使得VE(G)中相邻接或相关联的元素均着不同颜色的最少颜色数。证明了:如果ν(G)=ν(H),存在υ(?)V(G),υ'(?)V(H)使得G~c—υ和H~c—υ'都含有完美对集且△(G)=△(H)并存在e(?)E(G—υ),e'(?)E(H—υ'),使得G—e和H—e'都是第一类图,或△(G)<△(H)且存在e(?)E(H—υ')使得H—e'是第一类图,则x_T(GVH)≤△(GVH)+2g.  相似文献   

8.
设G是非平凡连通图,记c:V(G)→N是G的一个顶点染色,这里相邻的两个顶点可以着相同的颜色。对于图G的任一顶点v,与v相邻的顶点所着颜色的集称为v的邻色集,记为NC(v)。如果G中任意相邻的两个顶点u,v满足NC(u)≠NC(v),则称c是G的一个集合染色。集合染色所需的最少的颜色数称为G的集合色数,记为χs(G)。本文给出了与轮图有关的一类平面图的集合色数,向日葵图和风车图的集合色数,最后给出了一个猜想。  相似文献   

9.
图的点强全染色   总被引:1,自引:1,他引:0  
朱海洋  郝建修 《河南科学》2005,23(5):642-646
图G(V,E)的正常k—全染色f叫做G(V,E)的k—点强全染色,当且仅当对任意的w∈V(G),N[w]中元素染不同颜色,其中N[w]={x|wx∈E(G)}∪{w}.并称XvTs(G)=min{k|存在G的k—点强全染色}为图G(V,E)的点强全色数.本文研究了K4-minor free图和外平面图的点强全色数.  相似文献   

10.
对于图G=(V,E)的一个正常全染色,用C(v)表示顶点v∈V的颜色以及与v关联的边的颜色构成的集合,称之为点v∈V的色集合.如果C(u)≠C(v),那么就说u和v被该全染色所区别.一个图G的d-强全染色是指使得满足1≤dG(u,v)≤d的任意一对顶点u和v可区别的一个正常全染色.所谓一个图G的d-强全色数是指对图G进行d-强全染色所需要的颜色的数目的最小值.文中对当d∈[35,55]时圈的d-强全色数进行了确定.  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

19.
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   

20.
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