基于用户聚类分析的网站导航结构智能优化研究与实现

为了提高用户的兴趣空间，对网站导航结构优化进行了分析，提出了对Web日志进行数据预处理算法，同时提出了将用户每次访问的session数据合并为反映用户访问兴趣的数据方法，再对合并后的数据采用BIRCH算法进行聚类分析，最后根据用户聚类分析的结果提出网站导航结构智能优化的方法，给出了一个根据用户聚类集合动态调整导航的结构模型。     

基于多Agent的Web个性化信息检索模型

提出了一种基于多Agent的Web个性化信息检索系统的模型(WPIRS-MA),该模型利用多智能Agent技术,结合用户的关键词描述,挖掘用户潜在的兴趣和特征,在各Agent的协调下,完成信息检索、过滤和聚类.框架分析表明该模型具有良好的灵活性、智能型和扩展性.基于5个站点的Web文档测试分析结果表明,该模型可以保证良好的关键词集的正确率,用户查询满意度达到80%以上.     

一种网络智能信息Agent--CIRs的设计

Web上大量、分布、动态的信息,造成了用户在查询Web上的信息时产生“信息过载”和“信息迷向”现象．智能信息Agent是解决此问题的研究热点．设计并实现了一种以智能化、主动搜索为标志的互联网智能信息Agent-CIRs,从用户日常的行为中自动学习出用户兴趣模型,从而为用户提供个性化Web信息服务．     

高校图书馆搜索引擎中Web挖掘的应用研究

针对高校学术信息资源检索的精确度问题,提出了运用Web挖掘的高校图书馆搜索引擎系统。它主要对Web使用记录挖掘及其用户兴趣模型的建立进行了详细分析。首先它阐述了高校图书馆搜索引擎系统的4个过程,其中主要提出建立用户兴趣模型时采用的一种利用用户浏览页面集的内容信息和浏览行为信息,隐式地创建用户兴趣描述文件的方法;然后阐述了高校图书馆搜索引擎系统的各处理模块;最后设计了结合Web数据挖掘的高校图书馆搜索引擎系统操作过程,保证了所创建的用户兴趣模型的准确性,从而有效地提高高校图书馆搜索引擎系统的查准率。     

图书馆文献信息资源智能推荐检索平台设计

针对当前方法设计的图书馆文献信息资源推荐检索平台存在的检索效率低和召回率低的问题,提出图书馆文献信息资源智能推荐检索平台设计方法。通过平台架构、检索接口、平台功能设计构成图书馆文献信息资源智能推荐检索平台的框架,其中平台架构设计包括信息库连接和可视化信息,根据数学工具和语言完成图书馆文献信息资源智能推荐检索平台中检索接口设计,平台功能包括资源显示、资源检索、信息编辑和空间分析。将隐式方法与显示方法相结合构建用户兴趣模型,在用户兴趣模型的基础上通过冷启动阶段和推荐阶段完成图书馆文献信息资源的智能推荐和检索。实验结果表明,所提方法可在较短的时间内完成图书馆文献信息资源的推荐和检索,且检索得到的资源完整度较高,验证所提方法的检索效率高、召回率高。     

面向智能搜索引擎的用户兴趣特征模型研究

通过直接学习和反馈学习来挖掘智能搜索引擎用户的兴趣特征信息,并建立了兴趣特征库。提出了通过用户兴趣特征增量算法自动修改用户的兴趣特征权值。最后通过实例验证了用户兴趣特征模型在检索中应用的意义。     

基于用户聚类分析的网站导航结构智能优化研究与实现

为了提高用户的兴趣空间,对网站导航结构优化进行了分析,提出了对Web日志进行数据预处理算法,同时提出了将用户每次访问的session数据合并为反映用户访问兴趣的数据方法,再对合并后的数据采用BIRCH算法进行聚类分析,最后根据用户聚类分析的结果提出网站导航结构智能优化的方法,给出了一个根据用户聚类集合动态调整导航的结构模型。     

根据用户隐式反馈建立和更新用户兴趣模型

提出一种通过获取用户的隐式反馈信息建立和更新用户兴趣模型的方法．这种方法不需要用户显式地提供兴趣信息，只要通过观察用户在浏览Web页面时所采取的动作来获取隐式的反馈信息，并利用这些信息建立与更新用户兴趣模型，从而减轻用户的负担．     

一种基于Web挖掘的信息自动分类系统

探讨了Web挖掘的相关理论，包括Web文本信息的表示及特征提取，关联规则分析和信息分类，综合Web挖掘的关键技术，提出了一个基于Web挖掘技术的信息分类模型系统，使用户能够对已分类的资源进行浏览、检索，从而更方便、快捷地获取所需信息。     

一种基于网页元数据的用户访问行为建模方法

针对现有行为建模方法难以描述行为语义的问题,提出了一种分层次的用户行为元模型以及一种基于页面元数据的Web用户行为建模方法.该方法从URL的访问、活动、事务3个层次建立Web用户的行为模型,并对页面元数据获取以及在URL的访问、行为、事务之间转化等问题进行了说明.方法及模型不仅描述了用户访问序列信息,还增加了访问内容的局部主题和关键词等信息,为进一步获取Web用户的行为语义特征奠定了很好的基础.通过西安交通大学的Web教学系统验证表明,利用所提方法获得的序列划分准确率达86%以上.     

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.     

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.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the