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1.
可靠性分析的并行不交和算法   总被引:1,自引:0,他引:1  
不交和算法是计算网络可靠性的有效方法,到目前为止,基于这一方法已经开发出多种算法,提出了对这些不交和算法实行并行化的通用框架,基于这个框架,在工作站网络上实现CAREL不交和算法的并行化版本,实验结果表明,这种方法效果很好,几乎得到线性加速。  相似文献   

2.
利用基于基本互补划分(ECP)求复杂网络的树的原理,发展了一种新的求不交化树的方法,从而能有效地计算一个复杂网络的全可靠度  相似文献   

3.
网络可靠度一种新的不交和算法   总被引:1,自引:0,他引:1  
给出网络可靠度一种新的不交和算法,对两终端可靠度而言,当给出两终端道路集合后,撮一种排列道路顺序的新原则,利用不交和算法,在计算中借助布尔代数,定理进行简化,使得算法步骤较少而可靠度的符号表达式更加紧凑。  相似文献   

4.
基于网络简化技术的通风网络可靠度新算法   总被引:1,自引:0,他引:1  
为了解决在网络可靠度计算中存在运算量过大的问题,利用不交和的原理计算网络的可靠性是当今所有计算网络可靠性方法中最有效的方法之一,但对大型网络依然无法快速确定网络可靠度。针对这一问题,采用直接构造不交化通路集的方法,结合网络简化技术和截断误差理论,提出了一种快速确定大型通风网络可靠度的算法。结果表明:本算法可在24 s内计算出传统算法10 h都无法算出的大型通风网络可靠度问题。该算法对提高大型通风网络可靠度计算速度具有很大作用。  相似文献   

5.
介绍了初等有向树变换的概念,并基于初等有向树变换给出了一种计算广播型网络可靠度的新方法,该方法不需进行非独立事件和的概率计算或有向树的专门不交化处理,因而所需计算量较小。  相似文献   

6.
边不交生成树的研究在互连网络并行广播通讯中具有重要的理论意义和应用价值。设Γ(Qn)为超立方体Qn中以vo为根节点的全体边不交生成树的集合,本文主要讨论|Γ(Qn)|的上界和下界,得到下列结果:(1)|Γ(Qn)|≤n·2n-12n-1,(2)当n≥4时,|Γ(Qn)|≥2。这些结果为设计超立方体互连网络中并行广播路由算法提供了理论依据。  相似文献   

7.
本文研究了目前比较流行的并行化方法,并分别使用了基于任务分解的方法.基于分治模式的方法,基于主从模式的方法对粒子群算法(PSO算法)进行了并行化实现,分析了并行PSO算法的优势,并提出其适用范围。  相似文献   

8.
复杂装置网络可靠性评估模型与算法   总被引:1,自引:0,他引:1  
研究了多状态、全终端复杂网络系统可靠性分析问题,通过使用结构函数设计了网络可靠性评估模型,并利用生成树的特性和网络图的环和理论,给出了多状态、全终端复杂装置网络可靠性分析的新算法·本算法并不需要全体生成树和全体割集作为前提条件,也不需要两次使用不交和运算,仅仅从一颗生成树开始,就可确定该网络的可靠性·该方法与传统方法比较,不仅降低了该类问题算法的计算复杂性,而且提高了评估过程的准确性、可操作性·大量实例计算表明了模型与算法的可行性与有效性·  相似文献   

9.
针对基于极大团的社区发现算法,设计了适应大规模数据的MapReduce并行计算框架,提出了基于大规模复杂网络社区发现的科研合著网络分析算法,并用于对我国管理科学与工程领域2012年科研合著网络进行社区结构划分。实验结果表明,基于MapReduce的并行社区发现算法可在保证正确性的同时有效提高计算效率,适用于大规模复杂网络的社区发现。针对我国管理科学与工程领域2012年科研合著网络的社区划分结果展现了我国管理科学与工程领域科研合作的特点和问题。  相似文献   

10.
提出了求通信网络生存能力的快速表格算法 ,用该算法来处理布尔代数中的不交化运算 ,很少产生冗余项 ,具有简单、快速、高效的优点 .  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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