• Journal of the Korean Society for information Management
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• v.17 no.3
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• pp.147-170
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• 2000

RDF treats all resources independently, that's integrated description model for internet resources description, that provides the model to connect resources that related with the specific resources. This article performs theoretical review of RDF model and syntax specification and RDF schema specification that's a common rule of semanics, structure and syntax those provides search and access in the area of dispersed information environment of internet and Dublin Core that's description element for build metadata. And with this way it's materialized metadata design, schema, DTD of Dublin Core element for building RDF-based metadata that is XML application.

• Journal of Digital Contents Society
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• v.9 no.2
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• pp.285-293
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• 2008

In Semantic Web, metadata and ontology for representing semantics and conceptual relationships of information resources are essential factors. RDF and RDF Schema are W3C standard models for describing metadata and ontology. Therefore, many studies to store and retrieve RDF and RDF Schema documents are required. In this paper, we focus on some results of analyzing available query patterns considering both RDF and RDF Schema and classify queries on RDF and RDF Schema into the three patterns. RDF and RDF Schema can be represented as graph models. So, we proposed some strategies to store and retrieve using the graph models of RDF and RDF Schema. We can retrieve entities that can be arrived from a certain class or property in RDF and RDF Schema without a loss of performance on account of multiple joins with tables.

• Journal of the Korean Society for information Management
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• v.20 no.3
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• pp.241-259
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• 2003

The Basic Semantic Register(BSR) is and official ISO register designed for interoperability among eBusiness and EDI systems. The entities registered in the current BSR are not defined in a machine-understandable way, which renders automatic extraction of structural and relationship information from the register impossible. The purpose of this study is to offer a framework for designing an ontology that can provide semantic interoperability among BSR-based systems by defining data structures and relationships with RDF and OWL, similar meaning by the 'equivalentClass' construct in OWL, the hierachical relationships among classes by the 'subClassOf' construct in RDF schema, definition of any entities in BSR by the 'label' construct in RDF schema, specification of usage guidelines by the 'comment' construct in RDF schema, assignment of classes to BSU's by the 'domain' construct in RDF schema, specification of data types of BSU's by the 'range' construct in RDF schema. Hierarchical relationships among properties in BSR can be expressed using the 'subPropertyOf' in RDF schema. Progress in semantic interoperability can be expected among BSR-based systems through applications of semantic web technology suggested in this study.

• Journal of the Korea Society of Computer and Information
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• v.14 no.1
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• pp.173-181
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• 2009

This paper proposes an algorithm to transform RDF(Resource Description Framework) models for ontology into CPN(Colored Petri Net) models. The algorithm transforms the semantics of the RDF model into the topology of the CPN by mapping the classes and the properties of the RDF onto the places of the CPN model then reflects the RDF statements on the CPN by representing the relationships between them as token transitions on the CPN. The basic idea of reflecting the RDF statements on the CPN is to generate a token, which is an ordered pair consisting of two tokens (one from the place mapped into the subject and the other one from the place mapped into the object) and transfer it to the place mapped into the predicate. We have actually built CPN models for given RDF models on the CNPTools and inferred and extracted answers to the RDF queries on the CPNTools.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.2
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• pp.49-63
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• 2008

RDF is the base ontology model which is used in Semantic Web defined by W3C. OWL expands the RDF base model by providing various vocabularies for defining much more ontology relationships. Recently Jain and Farkas have suggested an RDF access control model based on RDF triple. Their research point is to introduce an authorization conflict problem by RDF inference which must be considered in RDF ontology data. Due to the problem, we cannot adopt XML access control model for RDF, although RDF is represented by XML. However, Jain and Farkas did not define the authorization propagation over the RDF upper/lower ontology concepts when an RDF authorization is specified. The reason why the authorization specification should be defined clearly is that finally, the authorizatin conflict is the problem between the authorization propagation in specifying an authorization and the authorization propagation in inferencing authorizations. In this article, first we define an RDF access authorization specification based on RDF triple in detail. Next, based on the definition, we analyze the authoriztion conflict problem by RDF inference in detail. Next, we briefly introduce a method which can quickly find an authorization conflict by using graph labeling techniques. This method is especially related with the subsumption relationship based inference. Finally, we present a comparison analysis with Jain and Farkas' study, and some experimental results showing the efficiency of the suggested conflict detection method.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1546-1549
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• 2008

유비쿼터스 시스템이 발전함으로 많은 사람들이 시스템을 사용함으로 인하여 정보보호에 대한 중요성이 증대되고 있다. 본 논문에서는 유비쿼터스 시스템에서 데이터를 표현하기 위하여 널리 사용되는 RDF/S가 정보보호에 대하여 취약함에 주목하고 RDF/S에 대한 정보보호를 위한 RDF/S 스키마와 추론에 필요한 규칙을 소개한다.

• Transactions of Materials Processing
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• v.20 no.2
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• pp.154-159
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• 2011

The roll die forming (RDF) process is a new manufacturing technique for producing gear parts such as clutch drum and clutch hub in automotive transmission. In the RDF process, the material is deformed by a roll installed on a die set. Excellent productivity, low forming load and improved dimensional accuracy have quantitatively been shown to be the benefits of the RDF. In this study, the RDF process is applied to manufacture a clutch hub with a gear shaped part. A finite element (FE) analysis was performed in order to investigate the material strain field and dimension of the final product. Based on the result of the FE analysis, a RDF experiment was performed and the dimensional accuracy of the final product was validated. This work demonstrates that RDF is a process capable of producing a sound clutch hub.

• Journal of KIISE:Databases
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• v.35 no.2
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• pp.132-142
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• 2008

In biological domain, there exist a variety of protein analysis databases which have their own meaning toward the same target of protein. If we integrate these scattered heterogeneous data efficiently, we can obtain useful information which otherwise cannot be found from each original source. Reflecting the characteristics of biological data, each data source has its own syntax and semantics. If we describe these data through RDF(S) models, one of the Semantic Web standards, we can achieve not only syntactic but also semantic integration. In this paper, we propose a new concept of integration layer based on the RDF unified schema. As a conceptual model, we construct a unified schema focusing on the protein information; as a representational model, we propose a technique for the wrappers to aggregate necessary information from the relevant sources and dynamically generate RDF instances. Two example queries show that our integration layer succeeds in processing the integrated requests from users and displaying the appropriate results.

• The Journal of the Korea Contents Association
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• v.15 no.1
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• pp.9-23
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• 2015

In this paper, we propose a new RDF index scheme considering the characteristics of large scale RDF data to improve the query processing performance. The proposed index scheme creates a S-O index for subjects and objects since the subjects and objects of RDF triples are used redundantly. In order to reduce the total size of the index, it constructs a P index for the relatively small number of predicates in RDF triples separately. If a query contains the predicate, we first searches the P index since its size is relatively smaller compared to the S-O index. Otherwise, we first searches the S-O index. It is shown through performance evaluation that the proposed scheme outperforms the existing scheme in terms of the query processing time.

• Journal of Korean Library and Information Science Society
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• v.48 no.3
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• pp.233-257
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• 2017

In this paper, we propose an effective method to convert and construct the MEDLINE, the world's largest biomedical bibliographic database, into linked data. To do this, we first derive the appropriate RDF schema by analyzing the MEDLINE record structure in detail, and convert each record into a valid RDF file in the derived schema. We apply the dual batch registration method to streamline the subject URI duplication checking procedure when merging all RDF files in the converted record unit and storing it in a single RDF triple storage. By applying this method, the number of RDF triple storage accesses for the subject URI duplication is reduced from 26,597,850 to 2,400, compared with the sequential configuration of linked data in units of RDF files. Therefore, it is expected that the result of this study will provide an important opportunity to eliminate the inefficiency in converting large volume bibliographic record sets into linked data, and to secure promptness and timeliness.