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1.
星图S_(n,k)的h-嵌入连通度ζ_h(S_(n,k))(h-嵌入边连通度η_h(S_(n,k)))被定义为顶点子集(边子集)的最小基数,如果存在,将其删除后Sn,k不连通而且连通分支的每个顶点都位于h-维的子网络Sh,l,其中0≤h≤n-2且l≤k.本文研究了星图S_(n,k)的h-嵌入(边)连通度,对于k=2,3和0≤h≤n-2,确定了ζ_h(S_(n,k))和ηh(S_(n,k))的值.  相似文献   

2.
主要研究了星图网络Sn的定向图.证明了如下结论:对于非负整数a和b,若存在满足每个顶点的入度或者是a或者是b的一个Sn的定向图,则存在非负整数s和t满足方程s+t=n!和as+bt=(n-1)/2.进一步,对于满足特定条件的非负整数a,b和n,存在Sn的定向图使得每个顶点的入度或者是a或者是b.  相似文献   

3.
利用超立方体的拓扑结构,基于其内部节点编码的特点,分析研究得到在n维超立方体Qn中任意两节点s、t之间经过k(kn)个指定点的最短路径算法.该算法共包括了十个步骤,在最坏的情况下执行2n~2+2n(n~2+2)次运算,算法的时间复杂度为O(n~3),属于多项式计算.  相似文献   

4.
讨论了球面Sn+1中具有常平均曲率H的紧致超曲面Mn的分类.设Mn是Sn+1中具有常平均曲率H的紧致超曲面,若s≤2n-1,则有1)M是Sn(r),r=11+H2;或者2)s=2n-1此时M或是Sn(r0),r20=n(n-1+1),s2=n-1(n-1+1).(n+2n-1);或是S-1(r)×Sn-1(s),r2=1  相似文献   

5.
集合{1,2,…,n}中取4个数字的所有组合,经三角排序后任意相邻2个组合都有3个相同数字.利用此结果和组合性质(n+8k3)-(n3)≡0 (mod 4)构造算法,并证明当n=11+8k(k =0,1,…)和(n-14)/2+2<m≤(n4)/2+2时积图Pm×P3的点可区别全色数为n.  相似文献   

6.
差商展开系数的递推公式和算法   总被引:1,自引:1,他引:0  
推导出了差商展开系数的一个递推公式 ,基于该公式给出了计算差商展开系数的一个新算法 .本算法比已有的算法更易于理解和实现 ,而且可同时计算一个节点向量上多个相邻的 k阶差商的展开系数 .当计算一个节点向量上的所有 k阶差商的展开系数时 ,本算法效率较高 ,时间复杂性为 O( k2 max( k,n +1 ) ) ,其中 k为差商的阶 ,n +k +1为节点向量所含的节点数  相似文献   

7.
设G是一个简单图且D是G的一个定向图.若对D中任意顶点x,d-(x)=a或b,则称G是[a,b]可实现的.主要研究了2维Torus网络中[a,b]可实现的充要条件.设H=Torus(p,k)是一个2维Torus网络,其中p和k是2个不小于3且奇偶性相同的正整数.设0≤a,b≤4,则H是[a,b]可实现的当且仅当存在非负整数s和t使得s+t=kp且as+bt=2kp.  相似文献   

8.
本文研究了给定指数n+s(n-2)的本原有向图的哈密尔顿性质,并得到如下结果:(1)设D是围长为s≥2,指数为n+s(n-2)的n阶本原有向图,如果D中有一个r-圈,使降(r,s)=1.则D是哈密尔顿的。(2)设D是包含环,指数为2n-2的n阶本原有向图,则D是哈密尔顿的充要条件是d(D)=n-2,这里d(D)是使γ(n,v)=γ(D)的n到v的最大距离。  相似文献   

9.
梯图的点可区别全染色(n≡2(mod8))   总被引:1,自引:0,他引:1       下载免费PDF全文
集合{1,2,…,n}中取4个数字的所有组合经三角排序后任意相邻两个组合都有3个相同数字.利用此结果及组合性质((n+8k 3)-(n 3))≡0(mod4)构造算法,并证明当n≡2(mod8)和(n-1 4)/2+2m≤(n 4)/2+2时,梯图LmPm×P2的点可区别全色数为n.  相似文献   

10.
定义了有向双环网络G(N;r,s)新的路由模型--二叉树模型,给出了O节点到二叉树模型任意一层节点的最短路径的路南策略.证明了有向双环网络的直径等于其二叉树的树高,研究了任意两节点之问的最短路径与其所在层及其相应位置的关系,给出有向双环网络任意两节点最短路径的算法.运用此算法,只需简单的算术运算和关系运算,就能快速求出任意两节点的最短路径.  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.
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   

18.
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   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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