CAJ | 학술논문

关联数据的目标是使客户端应用通过跟踪RDF链接发现新的数据源，实现对不同数据集的平滑整合，但现有方法创建的RDF链接十分有限，为此德国柏林自由大学于2010年提出面向RDF数据集映射的R2R语言。该语言包括r2r：prefixDefinitions，r2r：sourcePattern，r2r：targetPattern，r2r：transformation，r2r：mappingRef等映射属性，字符串函数、列表函数、算术函数、XPmh函数及URI、文字、语言、数据类型等四种变量修饰符，提供r2r：has-Mapping，r2r：mapsTo，r2r：dependsOn，r2r：sourceDataset，r2r：targetDataset等映射元数据，映射语句遵循“资源-映射属性-三元组文字”结构及Turtle语法等规则。在总结以上语法框架的基础上通过实例阐释其用法，并与SPAR-QL语言进行比较。研究认为R2R语言在支持RDF表示、变量和修饰符定义、名称空间前缀表示、空白节点定义变量等方面与SPARQL存在语法-致性特征，在功能和句法表示方面二者存在一定差别。推广R2R语言有助于从词汇和数据集实例两个层面提升RDF链接创建能力，进而为创建关联数据集成服务环境提供支持。图2。表7。参考文献21。
관련수거적목표시사객호단응용통과근종RDF련접발현신적수거원，실현대불동수거집적평활정합，단현유방법창건적RDF련접십분유한，위차덕국백림자유대학우2010년제출면향RDF수거집영사적R2R어언。해어언포괄r2r：prefixDefinitions，r2r：sourcePattern，r2r：targetPattern，r2r：transformation，r2r：mappingRef등영사속성，자부천함수、렬표함수、산술함수、XPmh함수급URI、문자、어언、수거류형등사충변량수식부，제공r2r：has-Mapping，r2r：mapsTo，r2r：dependsOn，r2r：sourceDataset，r2r：targetDataset등영사원수거，영사어구준순“자원-영사속성-삼원조문자”결구급Turtle어법등규칙。재총결이상어법광가적기출상통과실례천석기용법，병여SPAR-QL어언진행비교。연구인위R2R어언재지지RDF표시、변량화수식부정의、명칭공간전철표시、공백절점정의변량등방면여SPARQL존재어법-치성특정，재공능화구법표시방면이자존재일정차별。추엄R2R어언유조우종사회화수거집실례량개층면제승RDF련접창건능력，진이위창건관련수거집성복무배경제공지지。도2。표7。삼고문헌21。
The goal of linked data is to enable client application to discover new data sources by following RDF links and to smoothly integrate data from those sources. R2R language is an RDF dataset mapping language developed by Free U- niversity of Berlin to address the issue that RDF links created by existing methods are extremely limited. R2R includes mapping properties such as r2r： prefixDefinitions, r2r： sourcePattem, r2r： targetPattem, r2r： transformation, r2r： mappin- gRef; R2R functions consists of string, list, arithmetic and XPath functions; vamame modifiers includes URI, literals, lan- guage, datatype modifiers; mapping metadata includes r2r： hasMapping, r2r： mapsTo, r2r： dependsOn, r2r： sourceDataset, r2r： targetDataset; R2R syntax follows grammatical structure of “Resource-Mapping Property-Literal Value of Triples” and Turtle grammar. This paper summarizes the framework and demonstrates the usage with typical examples. Finally, we com- pare R2R with RDF-oriented query language SPARQL, and it shows that R2R shows some degree of grammatical consisten- cy with SPARQL in supporting RDF representation, defining varnames and modifiers, expressing prefixes of namespaces, and stating varnames with blank nodes. On the other hand, there are differences between R2R and SPARQL in functionality and syntax. In conclusion, R2R language will be helpful in creating more RDF links from terms of vocabularies and linked datasets, and supporting integrated services of linked data. 2 figs. 7 tabs. 21 refs.