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1.
在研究 JULIA集所具有混沌性质的基础上 ,给出了一种混沌吸引子的构造算法 .设定 N维空间中任意 M个坐标点 ,构造出 N个函数 ,使这 M个坐标点成为这些函数的根 ,并且使函数具有与 JULIA集相似的混沌性质 .文章最后给出了混沌仿真图形 .  相似文献   

2.
关联规则挖掘领域中的Apriori算法,其基本思想是组合枚举,然而要枚举出所有组合是一个困难的问题。本文从程序设计的角度对组合枚举算法进行了研究,给出了定义、定理和证明,设计了组合算法并在C#.NET中进行了实验,探讨了组合枚举算法的应用与不足。  相似文献   

3.
首先给出了一个新的核函数,该函数为两个核函数的凸组合,进而将该核函数应用于求解二阶锥规划原始对偶内点算法中.分析了算法的复杂性并得到了一个关于大步校正方法的迭代界.最后给出了数值试验结果,讨论了参数对算法的影响.  相似文献   

4.
在研究JULIA集所具有混沌性质的基础上,给出了一种混沌吸引子的构造算法,设定N维空间中任意M个坐标点,构造出N个函数,使这M个坐标点成为这此函数的根,并且使函数具有JULIA集相似的混沌性质,章最后给出了混沌仿真图形。  相似文献   

5.
为解决组合枚举择优问题,本文研究n进程组合调度算法,建立了把n重序元(x_1,x_2,…,x_n)映射到N上的正反公式.文中还给出“杨辉表”,以快速检索技巧代替二项式系数的计算,使算法适应实时要求.  相似文献   

6.
在图 G 的一个正常全染色下,G 中任意一点 v 的色集合是指点 v 的色以及与 v 关联的全体边的色所构成的集合。图 G 的邻点可区别全染色就是图 G 的正常全染色且使相邻点的色集合不同,其所用最少颜色数称为图 G的邻点可区别全色数。设计了一种启发式的邻点可区别全染色算法,该算法根据邻点可区别全染色的约束规则,确定四个子目标函数和一个总目标函数,然后借助染色矩阵及色补集合逐步迭代交换,每次迭代交换后判断目标函数值,当目标函数值满足要求时染色成功。实验结果表明,该算法可以得到图的邻点可区别全色数,并且算法的时间复杂度不超过 O(n3)。  相似文献   

7.
在组合几何基础上,对n点构图(任意3点均不共线)中的锐角三角形个数问题进行了研究.通过研究具体的n点构图,证明了平面上的9个点,至多可排出54个锐角三角形.对于一般的n点构图,证明了9个以上的点构成的三角形中至多有64.17%的锐角三角形,且对于任意n,必存在一个n点构图使得这n个点构成的三角形中至少有50%的锐角三角形.  相似文献   

8.
空间中的两个相交平面,可以构成四个二面角;对于平面外的任意点,必在其中一个二面角内;本文给出判别空间中两相交平面外两点位置关系的方法。  相似文献   

9.
林大志 《河南科学》2007,25(5):722-724
主要研究了平面上约束最优树的一个模型,其中直线L外有n个点,可以从直线L上引任意多直线,与n个点连接成连通网络,使总的连线长度最小.提出了新模型,并给出了一个有效算法.  相似文献   

10.
研究在给定长度下由格点构成的链的数目,并给出了关联函数的任意次幂的计算公式。利用序关系的对称性以及生成函数技巧,建立了对称型和Vandermonde型组合恒等式,推广了有关格路计数的结果。  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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

19.
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   

20.
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   

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