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1.
利用问题E2687解的一个充要条件,构造出一类新的本原Evans三角形,其三边长分别为k2-2+4k2(k2-2)(k2-1)3,1+4k2(k2-2)(k2-1)3,k2-1;且三角形中最短边上的高与该边长之比是4k(k2-2)(2k4-4k2+1)型的整数,其中k>1是正整数。  相似文献   

2.
设Fk表示k - fan,是由k个三角形组成的,且这些三角形恰好相交于一个公共顶点。 设Sn,k = Kk∇(n - k) K1,本文证明了在所有不含Fk的n阶图中,当α ∈ ( 1 2,1]、k ≥ 2且n ≥ 3k2 - k - 2 时,Sn,k是唯一获得最大Aα谱半径的图。  相似文献   

3.
本文给出了级数∑m k 部分和的组合表达式:m =1∞∑m k =f1k n +1()1+f 2 k m =1 k +()1+f n +2 k +3 k ()1+…f n +3 k +k k ()1, n +k k +并讨论了由这些系数构成的三角形的对称性以及此三角形内相邻行间元素的递归关系。  相似文献   

4.
正整数n的k部分分拆是将n表示成k个正整数的无序和.其中正整数n的3部分分拆的一个型应用是整边三角形.对于整边三角形的研究已经有许多结果,对于周长为n的整边三角形个数有一个估计数公式T(n).本文作者利用分拆的Ferrers图将整边三角形与不定方程4x1+3x2+2x3=n联系起来,给出了利用T(n)计算正整数n的一类4部分分拆数的计数式以及一类分部量不超过4的分拆数的计数公式,并讨论了其中一类分拆数在图论中的应用.  相似文献   

5.
k等周边连通度是一个比边连通度更可靠的网络可靠性参数。 连通图G的k等周边连通度定义为γk(G)=min{[X,X-]:XV(G),X≥k,X-≥k},其中X-=V(G)\X。令βk(G)=min{[X,X-]:XV(G),X=k}。图G是极大k等周边连通的如果γk(G)=βk(G)。令G是一个阶至少为6的连通图。本文证明了如果对于G中任意一对不相邻的顶点u,v,当u和v都不在三角形中时满足N(u)∩N(v)≥2;当u和v中至少有一个在三角形中时满足N(u)∩N(v)≥5,那么G是极大3等周边连通的。  相似文献   

6.
关于寻找有向连通图G=(V,E)的最小最大的k条弧不交路的问题是NP-完备的.研究这个问题的推广———有容量限制的k条路问题:①寻找k条路,使得k条路的费用之和尽可能小;②寻找k条路,使得k条路中最长的路的费用尽可能小.给出了问题①的一个最优算法,其复杂度为O(k|V|2),同时证明了该算法对于问题是k-近似的.  相似文献   

7.
关于Fibonacci三角形存在的上界   总被引:2,自引:0,他引:2  
何波 《广西科学》2005,12(4):249-249,254
运用G el'Fond-B aker方法,证明:对任意确定的正整数k>5,若存在以Fn,Fn+k,Fn+k为边长的F ibonacci三角形,则必有n相似文献   

8.
有限个单形间的几个不等式   总被引:3,自引:0,他引:3  
在通常情况下,我们所讨论的两个三角形,它们的边长与边长之间并无联系。本文所谈及的一些单形间的问题,它们之间的棱长具有一种有趣的联系。比如: 若△A_iB_iC_i的边长为a_i,b_i,c_i;面积为△_i,则以a'_i=(sum from k=1 to m α_k a_k~2)~(1/2), b~i=(sum from k=1 to m α_k b_k~2)~(1/2) ,c'_i=(sum from k=1 to m α_k c_k~2)~(1/2)为边长可以构成一个三角形A'B'C'。记△A'B'C'的面积为△',则有如下有趣的不等式  相似文献   

9.
设k为一个正整数,图G是一个顶点数为4k的简单图,当δ(G)≥2k+1时,文章证明了图G包含一个由k-3个4-圈,一个6-圈及一条至少包含三条弦的6-路构成的[1,2]-因子.  相似文献   

10.
给定一个阶为n的2-连通图G=(V;E)及一个正整数k,考虑在邻域并条件下G被分成k条点不交路的问题,得到下面的结果,对G中任何四个独立点x1,x2,y1,y2∈V,满足|NG(x1)∪NG(x2)| |NG(y1)∪NG(y2)|n-k,则G能被分划分k条点不交的路.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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