云环境下的产品知识获取及学习模型

根据云环境下的产品知识资源特点,给出了一个云环境下的产品知识获取框架,该框架由企业用户层、云知识平台层和知识资源层构成;建立了云环境下的产品知识获取过程模型,通过该模型进行产品设计、制造及服务等知识挖掘、收集、分析、归纳、整理和存储等;提出了云环境下的产品知识学习过程模型,通过该模型进行产品知识学习和传播,从而实现企业员工知识能力的提升。     

基于用户浏览时间的点击模型

用户的点击行为会受到用户的浏览行为、周围文档的特征等因素的影响,故在分析用户点击日志时不能直接将用户点击解释为文档相关性.为了更加准确地获得文档的相关性特征,文中提出了基于用户浏览时间的点击模型.假设文档原文的相关性会影响用户浏览该文档原文的时间,即文档越相关用户浏览文档的耗时越长,这样便可利用用户浏览文档的时间来推测...     

领域内用户浏览行为的用户需求知识发现研究

提出一种从用户浏览网页的行为中获取用户需求知识的方法.在领域内将产品进行需求项分解,从服务器日志中提取用户点击的网页及其次数,并计算出用户对每个需求项的值和可信度,由此可提取出用户以及用户群的需求知识.该方法不仅可以及时获取最近一段时间用户对现有产品指标的关注情况,还可以在一定程度上反映用户对该类产品的某些潜在需求,为企业进行新产品开发提供参考.     

基于用户行为模型的身份验证算法研究

身份认证技术是电子商务系统的重要环节。本文根据电子商务系统用户的特点，将网络入侵检测技术的思想引入用户身份验证，提出了基于用户行为模型的身份验证方案。该方案选择用户消费习惯、用户浏览时间以及用户键盘输入特性作为数据源，根据综合验证算法计算值与阈值对照，对用户身份进行验证。本文全面阐述了该身份验证方案的基本思想、测量点的选择和取值、以及综合验证算法等关键问题和解决方案；重点介绍了基于AHP方法的用户消费习惯模型的建立过程，以及利用该模型计算某种商品和用户期望值向量的相似度算法。     

基于马尔科夫模型和贝叶斯定理的Web用户浏览行为预测模型

对用户的Web浏览行为进行分析,既可以使用户减少等待时间,同时也能减轻网络负载.依据Web网站的层次结构特点,首先设计了基于Hash表的反向索引结构来提高数据的预处理速度;在此基础上,利用分层思想构建了基于马尔科夫模型和贝叶斯定理的Web用户浏览行为预测模型.给出了模型的设计思想、相关定义、模型框架以及模型中所涉及的关键构建方法等.最后,对模型进行了实验分析,结果表明在适当的预测准确率前提下,模型能够有效减少在预测时所需的候选网页数量,并大幅提升预测效率.     

网站用户偏好度的数据挖掘模型

数据挖掘和数据库知识发现是当前国际科技界的一个研究热点。这是一个介于统计学、模式识别、人工智能、机器学习、数据库技术以及高性能并行计算等领域的交叉新兴学科,具有极为广泛的应用前景。在基于统计学观点的基础上讨论了网站用户偏好度的数据挖掘模型,设计了一个网站用户信息浏览偏好度的数据挖掘模型。     

基于层次知识模型的知识库可视化研究

针对专家系统知识库可视化问题,构建了知识库的层次知识模型,基于径向树实现了层次知识模型的可视化.以基于多级知识单元的知识库为例,研发了知识库可视化系统,通过系统运行的实例验证了该方法能够方便用户快速浏览知识库的层次结构,从而有利于提高知识库的可理解性.该方法对其它知识表示方法的知识库可视化具有借鉴意义.     

基于Ontology的信息检索系统研究

为了减轻用户在检索信息过程中的负担,根据现有信息检索模型存在的问题,引入本体的概念,建立了一种基于本体的信息检索模型.该模型目标是根据浏览器的历史记录、用户浏览网页的浏览行为等,来更新用户兴趣模块,以不同用户的不同信息需求向用户推荐符合用户意图的信息,从而有效的提高信息检索的查全率和查准率.     

基于协同管理模式的企业员工招聘模型研究

通过对传统企业员工招聘模式的深入分析和研究,指出了该模式存在的不足,提出了基于协同管理模式的企业员工招聘模式,并在对该模式的原理、要点以及协同过程认真分析的基础上,运用可视化的统一建模语言(UnitedModelingLanguage,UML),从静态功能、动态活动以及系统实现等不同角度给出了该模式的可视化模型,为构建基于协同管理模式的企业员工招聘系统提供蓝图,最终实现企业员工招聘过程的快速化、集成化和有效化。     

手持设备上基于隐式反馈的网页兴趣块提取

为使用户在手持设备上提取用户兴趣是重要基础,提出一种基于用户隐式反馈的方法。该方法从网页中提取兴趣块(用户感兴趣的网页内容),假设用户的浏览行为如在块上的停留时间、滚动次数、滚动速度、进入链接的次数等与用户是否对块感兴趣相关。从手持设备上的浏览行为中提取了34种隐式反馈特征,通过分析18个用户在608个网页的9474个块上的浏览行为,验证了其中29种特征与兴趣块的相关性,并且这种相关性能用于跨用户、跨网站的兴趣块提取。该文的研究成果可用于建立个性化的用户偏好模型,应用在手持设备上的自适应网页浏览中。     

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.     

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.     

A computer generator for randomly layered structures

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

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

Exciton Seebeck in Molecular Systems

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     

Achieving Unusual States of Matter Under High Pressure

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

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.     

An improved R-tree based on childnode''s probability

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).     

Integrating GIS Web services based on mediating architecture

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.