• Title/Summary/Keyword: RDF/S

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A RDF based Ontology Management System (RDF 기반의 온톨로지 처리시스템)

  • Jung Jun-Won;Jung Ho-Young;Kim Jong-Nam;Lim Dong-Hyuk;Kim Hyoung-Joo
    • Journal of KIISE:Computing Practices and Letters
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    • v.11 no.4
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    • pp.381-392
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    • 2005
  • Computing has been making a lot of progress in the quantity of data, today. It's going to be more difficult to get appropriate information as the number of data increases dramatically. Therefore it's more important to get meaningful information than to focus on the speed of processing. Semantic web enables an intelligent processing by adding semantic information to data, and it is useful to make ontology system. In this Paper, we implemented ontology Processing system which support function for ontology and efficient processing for practical service. We proposed system design for independent from storage, storing technique for RDB, caching technique by schema information and useful user interface.

A Ranking Algorithm for Semantic Web Resources: A Class-oriented Approach (시맨틱 웹 자원의 랭킹을 위한 알고리즘: 클래스중심 접근방법)

  • Rho, Sang-Kyu;Park, Hyun-Jung;Park, Jin-Soo
    • Asia pacific journal of information systems
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    • v.17 no.4
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    • pp.31-59
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    • 2007
  • We frequently use search engines to find relevant information in the Web but still end up with too much information. In order to solve this problem of information overload, ranking algorithms have been applied to various domains. As more information will be available in the future, effectively and efficiently ranking search results will become more critical. In this paper, we propose a ranking algorithm for the Semantic Web resources, specifically RDF resources. Traditionally, the importance of a particular Web page is estimated based on the number of key words found in the page, which is subject to manipulation. In contrast, link analysis methods such as Google's PageRank capitalize on the information which is inherent in the link structure of the Web graph. PageRank considers a certain page highly important if it is referred to by many other pages. The degree of the importance also increases if the importance of the referring pages is high. Kleinberg's algorithm is another link-structure based ranking algorithm for Web pages. Unlike PageRank, Kleinberg's algorithm utilizes two kinds of scores: the authority score and the hub score. If a page has a high authority score, it is an authority on a given topic and many pages refer to it. A page with a high hub score links to many authoritative pages. As mentioned above, the link-structure based ranking method has been playing an essential role in World Wide Web(WWW), and nowadays, many people recognize the effectiveness and efficiency of it. On the other hand, as Resource Description Framework(RDF) data model forms the foundation of the Semantic Web, any information in the Semantic Web can be expressed with RDF graph, making the ranking algorithm for RDF knowledge bases greatly important. The RDF graph consists of nodes and directional links similar to the Web graph. As a result, the link-structure based ranking method seems to be highly applicable to ranking the Semantic Web resources. However, the information space of the Semantic Web is more complex than that of WWW. For instance, WWW can be considered as one huge class, i.e., a collection of Web pages, which has only a recursive property, i.e., a 'refers to' property corresponding to the hyperlinks. However, the Semantic Web encompasses various kinds of classes and properties, and consequently, ranking methods used in WWW should be modified to reflect the complexity of the information space in the Semantic Web. Previous research addressed the ranking problem of query results retrieved from RDF knowledge bases. Mukherjea and Bamba modified Kleinberg's algorithm in order to apply their algorithm to rank the Semantic Web resources. They defined the objectivity score and the subjectivity score of a resource, which correspond to the authority score and the hub score of Kleinberg's, respectively. They concentrated on the diversity of properties and introduced property weights to control the influence of a resource on another resource depending on the characteristic of the property linking the two resources. A node with a high objectivity score becomes the object of many RDF triples, and a node with a high subjectivity score becomes the subject of many RDF triples. They developed several kinds of Semantic Web systems in order to validate their technique and showed some experimental results verifying the applicability of their method to the Semantic Web. Despite their efforts, however, there remained some limitations which they reported in their paper. First, their algorithm is useful only when a Semantic Web system represents most of the knowledge pertaining to a certain domain. In other words, the ratio of links to nodes should be high, or overall resources should be described in detail, to a certain degree for their algorithm to properly work. Second, a Tightly-Knit Community(TKC) effect, the phenomenon that pages which are less important but yet densely connected have higher scores than the ones that are more important but sparsely connected, remains as problematic. Third, a resource may have a high score, not because it is actually important, but simply because it is very common and as a consequence it has many links pointing to it. In this paper, we examine such ranking problems from a novel perspective and propose a new algorithm which can solve the problems under the previous studies. Our proposed method is based on a class-oriented approach. In contrast to the predicate-oriented approach entertained by the previous research, a user, under our approach, determines the weights of a property by comparing its relative significance to the other properties when evaluating the importance of resources in a specific class. This approach stems from the idea that most queries are supposed to find resources belonging to the same class in the Semantic Web, which consists of many heterogeneous classes in RDF Schema. This approach closely reflects the way that people, in the real world, evaluate something, and will turn out to be superior to the predicate-oriented approach for the Semantic Web. Our proposed algorithm can resolve the TKC(Tightly Knit Community) effect, and further can shed lights on other limitations posed by the previous research. In addition, we propose two ways to incorporate data-type properties which have not been employed even in the case when they have some significance on the resource importance. We designed an experiment to show the effectiveness of our proposed algorithm and the validity of ranking results, which was not tried ever in previous research. We also conducted a comprehensive mathematical analysis, which was overlooked in previous research. The mathematical analysis enabled us to simplify the calculation procedure. Finally, we summarize our experimental results and discuss further research issues.

Characterization of inorganic materials in industrial waste and RDF using SEM-EDS (SEM-EDS를 이용한 산업단지폐기물과 고형연료의 무기 성분 규명)

  • Jeong, Moon-Heon;Lee, Ju-Ho;Yoo, Jeong-Kun;Lee, Gang-Woo;Shon, Byung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.10
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    • pp.2786-2793
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    • 2009
  • Recently, the development and spread of the new recyclable energy becomes urgent because of the depletion of fossil fuel and strengthening the environmental regulation. To recovery from the waste out of the many new recyclable energies has been proved as the most favorable when the potential value of energy source is compared. The RDF from the waste has been approved as the most economical method out of the other methods. However, the toxic gases (HCl, Dioxin etc) and heavy metals generated during the burning of the industrial wastes have been pointed out as problems. The PVC, alkali metal chloride, and alkaline earth metal chloride are major materials for emitting the chlorine and chlorine compounds have the problem such as the erosion on the heat collection device. This research has analyzed the heavy metal components containing in the industrial waste, and the concentration of Cl and S in the industrial waste generated in B industrial complex are slightly high than that of the A industrial complex. The results can be used to discuss the origin of inorganic components in industrial waste and utilized as a base data to improve the performance of the RDF as fuel.

A Study on Applications for Linked Data in Libraries (도서관에서의 Linked Data 활용방안에 관한 연구)

  • Cho, Myung-Dae
    • Journal of the Korean Society for Library and Information Science
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    • v.44 no.1
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    • pp.181-198
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    • 2010
  • In this paper, the necessity calling for a paradigm shift in information organization is summarized: an attempt is being made to move from a web of documents to a web of data. In this, the principles used to make a universal library network, as part of the semantic web, or linked data, are described. Popular RDF vocabularies are also briefly introduced emphasizing FRBR and RDA vocabularies. Some library-related linked data projects are also summarized, describing the steps necessary to make a library catalogue available as linked data, as well as a rationale for doing so. Lastly, proposed models for a universal library network focusing on linked data are suggested. Some implications for the use of library applications for linked data, among others, are also presented.

Design and Implementation of the RDF Web Ontology Access Control Model based on Oracle VPD (오라클 VPD 기반의 RDF 웹 온톨로지 접근 제어 모델의 설계 및 구현)

  • Jeong, Hye-Jin;Jeong, Dong-Won
    • Journal of the Korea Society for Simulation
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    • v.17 no.3
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    • pp.53-62
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    • 2008
  • This paper proposes a new implementational model based on the security model of Oracle for Web ontology. Recently, several access control models using relational database security model for access control to Web ontology have been developing, and one of the most representative access control model is the RAC model. However, the RAC model is based on the standard security model, and thus it does not provide a implementational model for practical relational database management systems. In this paper, we propose an implementational model based on Oracle which is widely used and providing various security policies. This paper shows the implementation and experimental evaluation. Especially, the proposed model uses the VPD security model of Oracle and support high application and usability.

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The extensible mapping rules for ontology integration (온톨로지 통합을 위한 변환 규칙의 확장)

  • Kim Sun-Kyung;Kim Byung-Gon;Lee Jae-Ho;Lim Hae-Chull
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.06c
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    • pp.115-117
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    • 2006
  • 웹에 대한 사용자의 다양한 요구와 더불어 시맨틱 웹에 대한 연구가 활발하게 이루어지고 있다. 이러한 연구 중에 대표적인 예가 바로 온톨로지의 구축에 대한 연구이다. ICS-FORTH는 온톨로지 구축을 위한 대표적인 시스템으로 SWIM을 이용한 분산된 환경에서의 독립된 온톨로지 즉, 관계형 데이터베이스와 XML로 된 온톨로지의 통합이 가능하도록 하였다. 또한, 통합된 온톨로지를 RDF/S를 기반으로 하는 뷰의 형태로 사용자에게 제공하여 추론이 가능한 질의 처리가 가능하도록 하였다. 이에 따라, 본 논문에서는 W3C에서 제안한 OWL을 통합의 대상으로 통합의 범위를 확장하기 위한 기법을 제안한다. 제안한 기법은 RDF/S를 확장한 다양한 관계의 기술이 가능하기 때문에 사용자가 RQL 형태의 질의를 미들웨어에서 처리할 수 있는 형태로의 변환하는 기존 기법의 확장된 형태이다. 이러한 확장을 통하여 기존 온톨로지 통합의 범위를 확장하여 보다 많은 사용자의 다양한 요구에 대응할 수 있다.

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Electronics and Telecommunications Research Institute (ETRI) (RDF와 XMI 메타프레임워크를 이용한 ebXML의 비즈니스 프로세스 명세 변환 기술)

  • 문진영;이대하;박찬규;조현규
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04d
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    • pp.355-357
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    • 2003
  • ebXML은 단일 세계 전자 시장의 형성을 목표로. UN/CEFACT와 OASIS의 주도로 만들어진 인터넷 상에서 기업간 전자 상거래를 위한 XML 기반의 표준 프레임워크이다. ebXML에서는 비즈니스 트랜잭션으로 구성되는 비즈니스 협업을 ebBPSS (ebXML Business Process Specification Schema) 스펙에 정의하는데, 기업의 비즈니스 시나리오를 기술하기 위해서 이 ebBPSS를 따르는 ebXML 비즈니스 프로세스 영세를 기술한다. 본 논문에서는 ebXML 비즈니스 프로세스 명세를 비즈니스 라이브러리에 저장하고, 서로 다른 시스템 사이에서 교환하기 위해 메타프레임워크인 XMI와 RDF 문서로 변환시키는 알고리즘을 제안한다. 이 알고리즘은 ebXML의 상호 운영성에 기여하여 ebXML 레지스터리에 저장된 비즈니스 프로세스 명세서의 유용성을 증대시킬 것이다.

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An XML Schema-based Semantic Data Integration (XML Schema기반 시맨틱 데이타 통합)

  • Kim Dong-Kwang;Jeong Karp-Joo;Shin Hyo-Seop;Hwang Sun-Tae
    • Journal of KIISE:Computer Systems and Theory
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    • v.33 no.9
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    • pp.563-573
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    • 2006
  • Cyber-infrastructures for scientific and engineering applications require integrating heterogeneous legacy data in different formats and from various domains. Such data integration raises challenging issues: (1) Support for multiple independently-managed schemas, (2) Ease of schema evolution, and (3) Simple schema mappings. In order to address these issues, we propose a novel approach to semantic integration of scientific data which uses XML schemas and RDF-based schema mappings. In this approach, XML schema al-lows scientists to manage data models intuitively and to use commodity XML DBMS tools. A simple RDF-based ontological representation scheme is used for only structural relations among independently-managed XML schemas from different institutes or domains We present the design and implementation of a prototype system developed for the national cyber-environments for civil engi-neering research activities in Korea (similar to the NEES project in USA) which is called KOCEDgrid (http://www.koced.net).

Database based Global Positioning System Correction (데이터베이스 기반 GPS 위치 보정 시스템)

  • Moon, Jun-Ho;Choi, Hyuk-Doo;Park, Nam-Hun;Kim, Chong-Hui;Park, Yong-Woon;Kim, Eun-Tai
    • The Journal of Korea Robotics Society
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    • v.7 no.3
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    • pp.205-215
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    • 2012
  • A GPS sensor is widely used in many areas such as navigation, or air traffic control. Particularly, the car navigation system is equipped with GPS sensor for locational information. However, when a car goes through a tunnel, forest, or built-up area, GPS receiver cannot get the enough number of satellite signals. In these situations, a GPS receiver does not reliably work. A GPS error can be formulated by sum of bias error and sensor noise. The bias error is generated by the geometric arrangement of satellites and sensor noise error is generated by the corrupted signal noise of receiver. To enhance GPS sensor accuracy, these two kinds of errors have to be removed. In this research, we make the road database which includes Road Database File (RDF). RDF includes road information such as road connection, road condition, coordinates of roads, lanes, and stop lines. Among the information, we use the stop line coordinates as a feature point to correct the GPS bias error. If the relative distance and angle of a stop line from a car are detected and the detected stop line can be associated with one of the stop lines in the database, we can measure the bias error and correct the car's location. To remove the other GPS error, sensor noise, the Kalman filter algorithm is used. Additionally, using the RDF, we can get the information of the road where the car belongs. It can be used to help the GPS correction algorithm or to give useful information to users.