Journal of the Korea Society of Computer and Information (한국컴퓨터정보학회논문지)

Korean Society of Computer Information (한국컴퓨터정보학회)
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A Common Shape Model To Obtain Multiple Schema Representations For RDF Knowledge Graphs Derived From RML Mappings

  • Ji-Woong Choi (School of Computer Science and Engineering, Soongsil University)
  • Received : 2024.10.17
  • Accepted : 2024.11.06
  • Published : 2024.11.29
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Abstract

In this paper, we propose a system to provide schemas written in multiple languages for RDF knowledge graphs derived from RML mappings. The core of the system is a common shape model designed to support both SHACL and ShEx, which are all languages for representing the structure of RDF graphs, called "shapes". The model is syntax-neutral, but includes enough data to represent constraints with the two schema languages. The data in the model are automatically collected from RML mapping rules themselves and metadata about input data sources in RML mappings. Also, the presented system provides a common interface to support translation of the model to multiple languages. The translation to each language is performed by each syntax-specific implementation of the interface, so the model data are rearranged according to each language's syntax. This paper describes the proposed method in detail and also presents implementation results.

본 논문에서는 RML 매핑으로 유도된 RDF 지식 그래프에 대한 스키마를 공통 형상 모델이라는 구조를 통해 여러 언어로 자동 생성해 주는 시스템을 제안한다. 형상이란 그래프 스키마 언어에서 그래프가 갖추어야 할 제약 조건의 집합을 뜻한다. 공통 형상 모델의 구조는 특정 스키마 언어의 구문에 독립적이다. 이 모델을 구성하는 데이터는 사용자가 RML 문법에 따라 정의한 매핑 규칙 그리고 RML 매핑에서 입력 자격인 다양한 포맷의 원천 데이터를 정해진 알고리즘에 따라 분석 및 가공 후 수집된 것들이다. 제안하는 시스템은 개별 스키마 언어들의 구문에 맞게 모델 데이터를 배열하는 방법을 정의할 수 있게 하는 공통 인터페이스를 제공한다. 즉, 개별 언어는 이 인터페이스를 구현하기만 하면 자신의 구문으로 스키마를 출력할 수 있다. 본 논문에서는 제안하는 방법의 실용성을 보이기 위해 대표적인 RDF 그래프 스키마 언어인 SHACL과 ShEx로 스키마를 출력하도록 구현하였으며 출력 스키마가 유효함을 보이는 테스트 결과를 제시한다.

Keywords

References

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