快速关联规则挖掘算法

提出了一种新颖的关联规则挖掘算法QAIS，与经典两阶段式关联规则挖掘算法不同的是，它只需扫描一遍事务数据库，不需要生成候选集，并且可以方便的应用在增量式关联规则挖掘算法中，该算法经合成数据验证是有效的．同时针对关联规则生成过程中出现大量冗余规则的问题，还讨论了冗余关联规则去除的问题．     

一种基于关联挖掘的缺省规则更新算法

为了解决缺省关联规则的增量挖掘问题,在算法DRMBAR的基础上,结合粗糙集理论及频繁模式树结构,提出了一种基于关联规则的缺省规则更新算法IADRBAR,该算法主要考虑最小支持度发生变化时缺省规则的更新问题,即在新的最小支持度下,如何高效地生成新的关联规则. IADRBAR在最坏的情况下仅须扫描决策表一遍,并利用上一次已经挖掘出的频繁项目集及关联规则,有效地提高缺省规则的更新效率.理论分析和实验结果表明算法是有效可行的.     

改进的关联规则采掘算法及其实现

在现有的关联规则采掘算法的基础上，进一步分析了经典算法的内涵，提出了生成大项目集优化时减少对交易数据库扫描次数的改进算法，并给出改进后的算法描述。在DBMS平台上用数据查询语言实现关联规则的采掘。结果表明，改进的算法对关联规则的采掘十分有效。     

关联规则挖掘的AprioriTid算法的改进

关联规则挖掘是数据挖掘中常见的一种形式。高效地找出频繁项目集是关联规则挖掘的中心问题．文章在分析生成频繁项目集的AprioriTid算法的基础上，指出了算法中存在由于项目的重复存储而使数据量偏大的问题，提出并证明了“Ck—l中支持率小于minsupport的项目集在Ck-1中是无用的”的定理。并以此为依据改进了算法．实验表明，改进算法在缩小数据规模方面是行之有效的．     

关联规则更新的新算法

考虑事务数据库D不变,项目集I发生变化时的关联规则挖掘问题.提出了两种关联规则更新算法,解决增加项目或减少项目时的关联规则更新问题.与重新运行一遍Apriori算法相比较,其运行效率有显著提高.     

改进的Apriori算法在中医医案分析中的应用

为了解决Apriori 算法的不足,提出了改进的Apriori算法:进行剪枝侯选项目集时,采用生成频繁项目集和删除具有非频繁子集候选同时进行的方法来减少多余子项目集的生成.改进的Apriori 算法大大提高了频繁项目集即关联规则生成的效率,运行时间不及原算法的十分之一,同时节省了大量的存储空间.最后利用改进的Apriori 算法对中医医案数据进行关联规则挖掘,获得了良好的效果.     

基于集合和剪枝原理的关联规则隐藏算法

针对传统关联规则隐藏算法直接遍历数据集,而导致输入输出流资源浪费的问题,提出一种基于集合和剪枝原理的关联规则隐藏算法。该算法首先建立频繁模式树(FP-tree),利用后剪枝原理去除属性相同规则,减少了遍历原始数据集所耗I/O时间;然后通过建立集合来保存真实频繁序列,并以集合为单位隐藏关联规则,既保证数据集质量,又提高频繁序列挖掘效率。实验结果表明,该算法与GSP、SPADE算法相比较,不仅更好地保证了数据集的高质量,而且降低了20%～50%频繁序列挖掘时间,并在隐藏敏感规则上有较好的实用性。     

基于多次学习和关联度的关联分类改进算法

基于支持度置信度框架的关联分类算法在生成规则时难以提出大量高质量规则,而且在一些数据集尤其是不平衡数据集上,部分训练实例未被产生的关联规则所覆盖,导致算法的分类准确率不高.基于以上问题提出了改进的关联分类的算法(Improved Algorithm based on Multiple learning and Correlation degree,IAMC).首先,在提取规则时,IAMC对训练集进行多次关联分类学习,尽量多地提出高质量的规则.其次,在生成规则时采用综合考虑了置信度,补类支持度的新度量关联度,以提高生成的规则的质量.最后,在关联分类规则提取后,对利用已有规则无法判断类别的和未被已有规则覆盖的训练实例用决策树方法再次提取规则,并加入到规则集中.实验结果表明,IAMC算法能提出更多高质量的规则,在多个UCI数据集上具有较高的分类准确率.     

一种基于关联规则的缺省规则挖掘算法

传统的基于Rough集的缺省规则挖掘算法须计算差别矩阵并生成大量的条件属性类，挖掘效率低．为此，本文引入相容关联规则和决策关联规则的概念，提出基于关联规则的缺省规则挖掘算法——DRMBAR，该算法借助FP-tree存储结构挖掘出决策关联规则，并用相容关联规则性质对决策关联规则进行有效修剪后生成相应的缺省规则,DRMBAR可有效地过滤噪声、提高缺省规则挖掘效率，且克服了传统算法依赖于主存的限制，为缺省规则的挖掘提供了一种新的框架。实验结果表明该算法是有效且可行的。     

关联挖掘在耕地流失原因分析上的应用研究

在传统算法的基础上,针对耕地流失原因分析时关心的规则后件只包含一个主要因素的特点,提出了改进的基于约束的频繁谓词集和关联规则生成算法,从而大大减少谓词集元素和无趣规则的数量,为该类问题提供了一个有效解决方法。实验证明该方法具有较好的有效性。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

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.     

Jane Eyre——A Feminist In The 19th Century

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-