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1.
"元数据模型"在数据提取中的实现   总被引:11,自引:1,他引:10  
大量分散的形式及不同格式的数据给现代数据处理带来了越来越大的困难.为统一数据形式以利于数据操作和处理,讨论了将形式多样的数据格式转换成统一的XML(extensible Markup Language)格式的问题.在计算机网络中,应用"元数据模型"技术,对数据源中不同格式文件数据,按照预先定义的XML模板,以格式说明文件结构统一描述,并提取数据或作进一步的处理,最后转换为XML格式输出.设计了具体的实现策略以及实现流程:实现了从TXT文件格式数据中提取数据转换成XML格式的代码,将TXT文件数据提取成XML格式的数据;完成了数据说明文件格式的设计,数据路径选择工具的开发,语言分析工具的设计开发等工作.结果表明:能满足同类产品的按行(line)为单位的源数据结构形式处理,还具有同类产品不具备的非行(字符串和关键字)提取处理功能.  相似文献   

2.
将XML技术应用到图形用户界面描述中,给出了一种新的图形用户界面自动生成方法,通过运用XML的特性,对界面元素进行规范化描述,通过GUI4J调用Java Swing组件库,动态生成基于Java Swing组件的图形用户界面.实践证明,将该方法应用于测试用例管理系统中,能够降低界面设计编程工作量,并在一定程度上提高软件的开发效率和可维护能力.  相似文献   

3.
陈博 《咸宁学院学报》2010,30(12):30-31
XML作为一种与平台无关的数据表示形式已经成为数据交换的主流语言,而关系数据库是核心业务系统中最常用的数据库技术,本文介绍了XML文档与关系模型之间的对应关系,基于ASP.NET利用DOM提取XML文档信息数据,编程实现了XML文档到关系数据库的转换.  相似文献   

4.
XML文档与关系数据库的数据转换研究   总被引:1,自引:0,他引:1  
可扩展标记语言(XML)作为一种与平台无关的数据表示形式,在企业应用程序中的使用正日益广泛,并成为web应用中数据传输与交换的标准,本文阐述XML与关系数据库的数据映射,并且讨论了SQLServer2000对XML的支持。  相似文献   

5.
异构数据库数据迁移测试软件的研究与实现   总被引:1,自引:0,他引:1  
指出了数据迁移测试领域中存在的问题.开发了异构数据库数据迁移测试软件,该软件使用JDBC接口连接访问数据库,采用XML文档存储测试数据,并建立了多层数据源结构,利用JDOM应用编程接口解析XML文档获取测试数据.该软件开发过程更加符合开发者的编程习惯,实现了测试数据的可重用以及DML语句的动态生成,达到了利用软件对迁移结果进行自动化测试的目的.  相似文献   

6.
在卫星遥感监测业务化运行系统中,简报是结果信息的重要载体.然而传统的简报生成工具存在强依赖于事先制定好的模板以及书签、不能重用等问题.在充分利用XML内容与形式分离这一特性的基础上,利用简报自动生成技术,设计并实现了从模板定制到简报生成的通用简报生成技术,为今后进行业务化运行提供技术支持.在卫星遥感监测业务化运行系统中的应用表明该技术是可行有效的.  相似文献   

7.
在面向服务理念的指导下,将具有分布性、协同性和异构性的仿真资源以服务的形式提出。应用面向服务的SOA架构技术和Web Services技术,根据建模规范对模型进行抽象描述,提炼出形式化模型函数。通过XML和XML Schema定义模型的互操作语法和语义,生成与平台和技术无关的XML描述文件。经过XML解析器解析后,将结果输入与平台和技术相关的代码生成器并自动生成各平台代码,并通过实例演示。  相似文献   

8.
一种新的Web链接提取模型   总被引:4,自引:0,他引:4  
以搜索引擎链接提取模块所要求的容错性、正确性、全面性、高效性和可扩展性为目标,提出了一种新的链接提取模型的设计思路。该模型将链接提取过程划分为信息提取、信息加工、信息分析和信息储存。信息的获取是通过HTM L(hypertex t m arkup language)文法分析方法从文档中得到初始统一资源地址(un iform resourceiden tifier,UR I)数据;信息加工阶段通过运用UR I解析算法对初始数据进行精练;然后在信息分析过程中进一步加以筛选和过滤;最后将结果存储在一个灵活的数据结构中。通过对比测试证实这种新的链接提取模式比传统方法在各项指标上均具有明显优势。  相似文献   

9.
本对当今正在兴起的一种新的可扩展标记语言XML作了概述,在此基础上,结合实例讨论了与XML相关的扩展语言的功能,包括名域、查询和链接、XML Schema、可扩展样式表语言(SXL)等,最后说明了与XML有关的开发活动。  相似文献   

10.
模板化网页主题信息的提取方法   总被引:37,自引:0,他引:37  
为了消除网页噪音,有效地提取基于模板的网页主题信息,提出了一种新的信息提取方法.该方法采用机器自动学习方式生成网页集的模板;以网页链接关系中的锚点文本作为提取目标对模板进行标记,生成对应模板的提取规则;依据模板的提取规则对网页主题信息进行提取.对国内2 588个新闻网页进行了检测.实验结果表明,该方法可以快速、有效地提取模板生成的网页集主题信息,准确率达99.5%.将该方法应用于搜索引擎系统(木棉检索)中,与原来的检索系统相比较,索引文件的大小减少约50%,检索的速度和精确度也得到提高.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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。  相似文献   

15.
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  相似文献   

16.
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  相似文献   

17.
18.
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.  相似文献   

19.
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).  相似文献   

20.
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.  相似文献   

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