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Data Transformation for Super-totalstation Positioning System Integrated by GPS and Totalstation 被引量:2
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作者 GUO Jiming ZHANG Zhenglu LUO Nianxue HUANG Quanyi 《Geo-Spatial Information Science》 2003年第1期38-42,共5页
This paper focuses on the integration and data transformation between GPS and totalstation.It emphasizes on the way to transfer the WGS84 Cartesian coordinates to the local two_dimensional plane coordinates and the or... This paper focuses on the integration and data transformation between GPS and totalstation.It emphasizes on the way to transfer the WGS84 Cartesian coordinates to the local two_dimensional plane coordinates and the orthometric height GPS receiver,totalstation,radio,notebook computer and the corresponding software work together to form a new surveying system,the super_totalstation positioning system(SPS) and a new surveying model for terrestrial surveying.With the help of this system,the positions of detail points can be measured. 展开更多
关键词 GPS TPS SPS data transformation
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Implementing Marine XML for Observed CTD Data in a Marine Data Exchange Platform 被引量:1
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作者 JIANG Yongguo FENG Yuan CHE Zhaodong ZHU Tieyi 《Journal of Ocean University of China》 SCIE CAS 2008年第4期393-396,共4页
In order to archive, quality control and disseminate a large variety of marine data in a marine data exchange platfonn, a marine XML has been developed to encapsulate marine data, which provides an efficient means to ... In order to archive, quality control and disseminate a large variety of marine data in a marine data exchange platfonn, a marine XML has been developed to encapsulate marine data, which provides an efficient means to store, transfer and display marine data. This paper first presents the details of the main marine XML elements and then gives an example showing how to transform CTD-observed data into Marine XML format, which illustrates the XML encapsulation process of marine observed data. 展开更多
关键词 marine data CTD marine xml marine data exchange
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Performances of Clustering Methods Considering Data Transformation and Sample Size: An Evaluation with Fisheries Survey Data
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作者 WO Jia ZHANG Chongliang +2 位作者 XU Binduo XUE Ying REN Yiping 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第3期659-668,共10页
Clustering is a group of unsupervised statistical techniques commonly used in many disciplines. Considering their applications to fish abundance data, many technical details need to be considered to ensure reasonable ... Clustering is a group of unsupervised statistical techniques commonly used in many disciplines. Considering their applications to fish abundance data, many technical details need to be considered to ensure reasonable interpretation. However, the reliability and stability of the clustering methods have rarely been studied in the contexts of fisheries. This study presents an intensive evaluation of three common clustering methods, including hierarchical clustering(HC), K-means(KM), and expectation-maximization(EM) methods, based on fish community surveys in the coastal waters of Shandong, China. We evaluated the performances of these three methods considering different numbers of clusters, data size, and data transformation approaches, focusing on the consistency validation using the index of average proportion of non-overlap(APN). The results indicate that the three methods tend to be inconsistent in the optimal number of clusters. EM showed relatively better performances to avoid unbalanced classification, whereas HC and KM provided more stable clustering results. Data transformation including scaling, square-root, and log-transformation had substantial influences on the clustering results, especially for KM. Moreover, transformation also influenced clustering stability, wherein scaling tended to provide a stable solution at the same number of clusters. The APN values indicated improved stability with increasing data size, and the effect leveled off over 70 samples in general and most quickly in EM. We conclude that the best clustering method can be chosen depending on the aim of the study and the number of clusters. In general, KM is relatively robust in our tests. We also provide recommendations for future application of clustering analyses. This study is helpful to ensure the credibility of the application and interpretation of clustering methods. 展开更多
关键词 hierarchical cluster K-means cluster expectation-maximization cluster optimal number of clusters stability data transformation
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XIDM: A Common Data Model Based on XML 被引量:2
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作者 Li Bing 1, Lu Zheng ding 1, Peng De chun 2 1.College of Computer Science & Technology,Huazhong University of Science & Technology,Wuhan 430074, China 2.State Key Laboratory of Software Engineering, Wuhan University,Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期432-437,共6页
Integration between file systems and multidatabase systems is a necessary approach to support data sharing from distributed and heterogeneous data sources. We first analyses problems about data integration between fil... Integration between file systems and multidatabase systems is a necessary approach to support data sharing from distributed and heterogeneous data sources. We first analyses problems about data integration between file systems and multidatabase systems. Then, A common data model named XIDM(XML\|based Integrating Dada Model), which is XML oriented, is presented. XIDM bases on a series of XML standards, especially XML Schema, and can well describe semistructured data. So XIDM is powerfully practicable and multipurpose. 展开更多
关键词 file systems multidatabase systems data integration xml
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Data Hiding and Security for XMLDatabase: A TRBAC-Based Approach 被引量:1
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作者 ZHANGWan-song SUNWei LIUDa-xin 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期293-296,共4页
In order to cope with varying protection granularity levels of XML(extensible Markup Language) documents, we propose a TXAC (Two-level XML. Access Control) framework,in which an extended TRBAC ( Temporal Role-Based Ac... In order to cope with varying protection granularity levels of XML(extensible Markup Language) documents, we propose a TXAC (Two-level XML. Access Control) framework,in which an extended TRBAC ( Temporal Role-Based Access Control) approach is proposed to deal withthe dynamic XML data With different system components, LXAC algorithm evaluates access requestsefficiently by appropriate access control policy in dynamic web environment. The method is aflexible and powerful security system offering amulti-level access control solution. 展开更多
关键词 xml data access control data security
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Discovering Frequent Subtrees from XML Data Using Neural Networks
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作者 SUN Wei LIU Da-xin WANG Tong 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期117-121,共5页
By rapid progress of network and storage technologies, a huge amount of electronic data such as Web pages and XML has been available on Internet. In this paper, we study a data-mining problem of discovering frequent o... By rapid progress of network and storage technologies, a huge amount of electronic data such as Web pages and XML has been available on Internet. In this paper, we study a data-mining problem of discovering frequent ordered sub-trees in a large collection of XML data, where both of the patterns and the data are modeled by labeled ordered trees. We present an efficient algorithm of Ordered Subtree Miner (OSTMiner) based on two- layer neural networks with Hebb rule, that computes all ordered sub-trees appearing in a collection of XML trees with frequent above a user-specified threshold using a special structure EM-tree. In this algo- rithm, EM-tree is used as an extended merging tree to supply scheme information for efficient pruning and mining frequent sub-trees. Experiments results showed that OSTMiner has good response time and scales well. 展开更多
关键词 xml frequent subtrees data mining neural networks
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A Dynamic XML-NS View Based Approach for the Extensible Integration of Web Data Sources
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作者 WUWei LUZheng-ding LIRui-xuan WANGZhi-gang 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期647-651,共5页
We propose a three-step technique to achieve this purpose. First, we utilize a collection of XML namespaces organized into hierarchical structure as a medium for expressing data semantics. Second, we define the format... We propose a three-step technique to achieve this purpose. First, we utilize a collection of XML namespaces organized into hierarchical structure as a medium for expressing data semantics. Second, we define the format of resource descriptor for the information source discovery scheme so that we can dynamically register and/or deregister the Web data sources on the fly. Third, we employ an inverted-index mechanism to identify the subset of information sources that are relevant to a particular user query. We describe the design, architecture, and implementation of our approach—IWDS, and illustrate its use through case examples. Key words integration - heterogeneity - Web data source - XML namespace CLC number TP 311.13 Foundation item: Supported by the National Key Technologies R&D Program of China(2002BA103A04)Biography: WU Wei (1975-), male, Ph.D candidate, research direction: information integration, distribute computing 展开更多
关键词 INTEGRATION HETEROGENEITY Web data source xml namespace
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Research and Realization of XML-based Heterogeneous Databases Integration
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作者 Yanxin Wang Kuihe Yang 《通讯和计算机(中英文版)》 2006年第3期109-113,共5页
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基于CIM XML的CIM和SCL模型互操作研究 被引量:30
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作者 罗建 朱伯通 +1 位作者 蔡明 赵国富 《电力系统保护与控制》 EI CSCD 北大核心 2011年第17期134-138,共5页
实现变电站系统与调度中心系统的信息交互,关键是实现系统模型的互操作。IEC61970、IEC61968的CIM模型和IEC61850的SCL模型在结构和内容上具有差异性,在详细讨论两种模型差异的基础上,基于XML,设计构造了文档转换器,实现XML文档和CIMXM... 实现变电站系统与调度中心系统的信息交互,关键是实现系统模型的互操作。IEC61970、IEC61968的CIM模型和IEC61850的SCL模型在结构和内容上具有差异性,在详细讨论两种模型差异的基础上,基于XML,设计构造了文档转换器,实现XML文档和CIMXML文档之间的转换。基于CIM模型和SCL模型的对应关系,通过对两种模型的类、属性、关系的协调,整合变电站模型,实现变电站系统模型与其它电力系统模型的互操作,保证数据的一致性。通过软件设计,经实验室模拟仿真,结果表明能够实现CIM模型和SCL模型在数据交换方面的要求。 展开更多
关键词 CIM SCL xml 互操作 数据交换
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Native XML数据库技术综述 被引量:13
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作者 逯鹏 吕良双 高庆一 《计算机科学》 CSCD 北大核心 2004年第4期84-88,共5页
XML成为数据统一描述和表示的标准。如何管理已经出现的大量的XML数据成为重要的问题。NativeXML数据库(NXD)是解决XML数据管理的重要手段。分析和综述了NXD研究现状,以及几个主要研究方向:数据模型、查询语言、存储技术等。分析了NXD... XML成为数据统一描述和表示的标准。如何管理已经出现的大量的XML数据成为重要的问题。NativeXML数据库(NXD)是解决XML数据管理的重要手段。分析和综述了NXD研究现状,以及几个主要研究方向:数据模型、查询语言、存储技术等。分析了NXD的基本特性和具有代表性的NXD系统,最后指出了目前研究存在的不足以及该学科的发展趋势。 展开更多
关键词 NATIVE xml 数据库 数据管理 数据模型 数据处理 数据库管理系统
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Java XML与面向Web的智能数据抽取 被引量:8
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作者 文艺 刘循 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第2期315-318,共4页
采用标准Web技术———HTML,XML和Java,开发一种基于Web用Java把Web数据转换为XML的数据挖掘方法.该方法标识数据源并把它映射成XHTML,根据一定的相关关系查找数据内的引用点并进行智能数据抽取,将数据映射成XML.这种数据抽取方法比较简... 采用标准Web技术———HTML,XML和Java,开发一种基于Web用Java把Web数据转换为XML的数据挖掘方法.该方法标识数据源并把它映射成XHTML,根据一定的相关关系查找数据内的引用点并进行智能数据抽取,将数据映射成XML.这种数据抽取方法比较简单,通过选择可靠的数据源以及在这些数据源中选取与内容相关但与格式无关的锚点,可以较为方便地建立一个强壮的数据抽取系统. 展开更多
关键词 xml XEITML XSL 数据抽取
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基于Native XML的武器装备体系需求建模数据管理 被引量:2
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作者 廖天俊 鲁延京 +1 位作者 杨克巍 谭跃进 《火力与指挥控制》 CSCD 北大核心 2010年第11期35-38,共4页
武器装备体系需求建模数据的规范化管理是武器装备体系需求分析的基础。针对目前武器装备体系需求建模缺乏统一的底层数据存储管理标准,在分析武器装备体系需求建模数据特征的基础上,以XML为数据载体,制定了基于Native XML数据库的存储... 武器装备体系需求建模数据的规范化管理是武器装备体系需求分析的基础。针对目前武器装备体系需求建模缺乏统一的底层数据存储管理标准,在分析武器装备体系需求建模数据特征的基础上,以XML为数据载体,制定了基于Native XML数据库的存储策略,设计并实现了基于典型Native XML数据库的武器装备体系需求建模数据管理方法,通过实践应用表明该方法能够为武器装备体系需求建模与分析环境提供有效的底层数据管理和分析支持。 展开更多
关键词 武器装备体系 需求建模 NATIVE xml数据库 数据管理
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DTD上的lazyDFA XML数据流查询优化算法 被引量:1
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作者 张晓琳 崔敏 谭跃生 《计算机工程与应用》 CSCD 北大核心 2009年第28期131-132,136,共3页
针对XML数据流上的XPath查询处理问题,基于自动机技术构造的lazyDFA查询处理器是一种有效的解决方法。为了提高lazyDFA的查询处理效率,提出了利用DTD的语义信息和结构信息对lazyDFA进行优化的算法。实验结果表明,优化算法可以有效的加快... 针对XML数据流上的XPath查询处理问题,基于自动机技术构造的lazyDFA查询处理器是一种有效的解决方法。为了提高lazyDFA的查询处理效率,提出了利用DTD的语义信息和结构信息对lazyDFA进行优化的算法。实验结果表明,优化算法可以有效的加快lazyDFA的查询速度,降低内存消耗。 展开更多
关键词 文档类型定义 lazyDFA 查询优化 xml数据流
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基于 XML 中间数据的异构数据库交换技术
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作者 李卫卫 《山东师范大学学报(自然科学版)》 CAS 2014年第1期33-38,共6页
随着信息化程度的不断提高,在多数企事业单位中,由于各个部门间一般采用的网络环境、操作系统和数据库系统都各有差异,形成了以各部门为核心的信息资源孤岛,数据共享和访问都比较困难.因此为解决这一问题,笔者首先介绍了基于 XML... 随着信息化程度的不断提高,在多数企事业单位中,由于各个部门间一般采用的网络环境、操作系统和数据库系统都各有差异,形成了以各部门为核心的信息资源孤岛,数据共享和访问都比较困难.因此为解决这一问题,笔者首先介绍了基于 XML的异构数据库数据交换方面的相关技术,重点讨论了关系数据和 XML 数据的转换问题.提出了一种新的异构数据库交换系统的体系结构,并在高校数字化校园平台的基础上,将异构数据库交换方案应用到该平台的各异构数据交换系统中,同时给出了数据抽取模式的算法.并采用了 C#语言及 ASP.NET 等相关技术对该系统中的各主要模块进行了详细的设计与实现,最后给出了实现的过程及数据交换的结果. 展开更多
关键词 异构数据库 数据交换 关系数据库
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Native XML数据库中文档和数据表现形式的分析与研究 被引量:2
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作者 安韶峰 鲁士文 《计算机应用与软件》 CSCD 北大核心 2004年第8期31-33,99,共4页
本文着重描述了NativeXML数据库中文档与数据之间的关系 ,分析并提出了它们的几种表现形式及表现方法。
关键词 NATIVE xml 数据库 文档 数据表现形式 数据处理
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基于Web Services的OPC XML-DA客户端的开发 被引量:2
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作者 查志铃 张浩 +1 位作者 樊留群 马玉敏 《机电一体化》 2009年第1期36-38,42,共4页
介绍了WebServices和OPCXML-DA技术,提出了基于WebServices技术的OPCXML—DA系统架构,通过示例说明了OPCXML—DA客户端的开发方法并给出了结果演示。
关键词 OPC xml—DA 数据采集 Web SERVICES 协同服务
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Applying XML for designing and interchanging information for multidimensional model 被引量:2
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作者 Lu Changhui Deng Su Zhang Weiming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期823-830,共8页
In order to exchange and share information among the conceptual models of data warehouse, and to build a solid base for the integration and share of metadata, a new multidimensional concept model is presented based on... In order to exchange and share information among the conceptual models of data warehouse, and to build a solid base for the integration and share of metadata, a new multidimensional concept model is presented based on XML and its DTD is defined, which can perfectly describe various semantic characteristics of multidimensional conceptual model. According to the multidimensional conceptual modeling technique which is based on UML, the mapping algorithm between the multidimensional conceptual model is described based on XML and UML class diagram, and an application base for the wide use of this technique is given. 展开更多
关键词 data warehouse OLAP multidimensional modeling conceptual model xml UML.
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基于形式语言理论的Active XML重写算法
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作者 马海涛 郝忠孝 《计算机工程》 CAS CSCD 北大核心 2009年第13期52-54,共3页
主动XML(AXML)是指一部分数据直接给出,另一部分数据以WebServices调用方式隐含给出XML文档。研究AXML重写问题,给出AXML重写系统的形式化定义,提出一个基于树自动机理论的AXML文档重写算法,并证明该算法的正确性及有效性。实验数据表明... 主动XML(AXML)是指一部分数据直接给出,另一部分数据以WebServices调用方式隐含给出XML文档。研究AXML重写问题,给出AXML重写系统的形式化定义,提出一个基于树自动机理论的AXML文档重写算法,并证明该算法的正确性及有效性。实验数据表明,基于树自动机的AXML文档交换方法具有良好的执行效率。 展开更多
关键词 主动xml 数据交换 文档重写 树自动机
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Efficient XML Query and Update Processing Using A Novel Prime-Based Middle Fraction Labeling Scheme 被引量:2
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作者 Zunyue Qin Yong Tang +3 位作者 Feiyi Tang Jing Xiao Changqin Huang Hongzhi Xu 《China Communications》 SCIE CSCD 2017年第3期145-157,共13页
XML data can be represented by a tree or graph and the query processing for XML data requires the structural information among nodes. Designing an efficient labeling scheme for the nodes of Order-Sensitive XML trees i... XML data can be represented by a tree or graph and the query processing for XML data requires the structural information among nodes. Designing an efficient labeling scheme for the nodes of Order-Sensitive XML trees is one of the important methods to obtain the excellent management of XML data. Previous labeling schemes such as region and prefix often sacrifice updating performance and suffer increasing labeling space when inserting new nodes. To overcome these limitations, in this paper we propose a new labeling idea of separating structure from order. According to the proposed idea, a novel Prime-based Middle Fraction Labeling Scheme(PMFLS) is designed accordingly, in which a series of algorithms are proposed to obtain the structural relationships among nodes and to support updates. PMFLS combines the advantages of both prefix and region schemes in which the structural information and sequential information are separately expressed. PMFLS also supports Order-Sensitive updates without relabeling or recalculation, and its labeling space is stable. Experiments and analysis on several benchmarks are conducted and the results show that PMFLS is efficient in handling updates and also significantly improves the performance of the query processing with good scalability. 展开更多
关键词 xml data structure information order information information separation PMFLS labeling scheme
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BloomRouter:A Framework for Dissemination of Compressed XML Stream
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作者 BAO Xiao-yuan TANG Shi-wei +2 位作者 YANG Dong-qing SONG Zai-sheng WU Ling 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期100-106,共7页
As our best knowledge, in the Publish/Subscribe application environment, few research work has been done on the dissemination and routing of compressed XML (extended markup language) data. A high-speed compressed XM... As our best knowledge, in the Publish/Subscribe application environment, few research work has been done on the dissemination and routing of compressed XML (extended markup language) data. A high-speed compressed XML data routing and dissemination framework BloomRouter is proposed. In BloomRouter, a Bloom Filter based prefilte ring mechanism is used to filter out compressed XML elements that users do not care; after that an interval tree dis seminator forwards target elements to the corresponding end users by matching the incomming compressed XML elements with indexed users' query regions. Based on this framework, we can efficiently filter/query the compressed incoming XML data, and then route the query result to the corresponding subseriber. 展开更多
关键词 xml bloom filters compression data stream
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