• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.605-613
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• 2004

Recently, the semantic web stands out in the next generation web. To realize the semantic web, the metadata integration is required between different metadatas on the web for metadata management. Otherwise, the integrated structure is needed to accommodate all of semantic, syntax and structure. RDF is one of the core technology and is more efficient framework for technology and interchange of metadata in the web, In this paper, for metadata management, we designed and implemented the RDF authoring system which converts each of metadata into RDF and makes it easy to manipulate and manage the different metadatas. For this, we researched about the RDF creation using Dublin Core metadata, the conversion of XML document into RDF, the RDF expression by N-Triple form and the integration of WSDL and RDF, and implemented the system on the lava platform. Basically, users using this system can integrate and manage metadatas easily even if they are not expert.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.110-116
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• 2021

W3C enacted RDF(Resource Description Framework based DCAT meta data standard, which is world-widely accepted so far. To guarantee the inter-operability and integrity of data from various sources and even from various countries, it is considered that transportation meta data should also follow the DCAT standard. But still, to represent the transportation domain-specific features, it is necessary to define new properties and vocabularies in addition to the DCAT standard. This research identified the additional properties and vocabularies for transportation metadata, considering uniqueness of transportation data. The revised RDF schema and RDF graph proposed in this research should be able to lead the transportation open data platform revitalization.

• Resources Recycling
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• v.12 no.4
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• pp.58-64
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• 2003

A study on the preparation of RDF with ASR materials from shredder line of end-of-life vehicles has been peformed by using hot molding method. ASR materials used in the work were plastics, fibers and sponge which were cut by less than 10 mm in size prior to hot molding and 40, 60 and 80 mm mold in diameter were employed for RDF forming. It was found that heating temperature, heating time and mixing ratio of materials played an important role in the hot molding of ASR materials. Density of RDF samples Prepared in the work was in the range of 0.5∼0.9gr/ml depending on the hot molding conditions and it was decreased with increase in the content of sponge. Breaking strength of RDF samples was observed to 0.8∼3.0MPa and it was also increased with increase in density of RDF samples. Finally, when heating temperature was elevated, density of RDF was increased due to Increase in molten part of ASR materials which resulted in the enhancement of breaking strength of RDF.

• Journal of KIISE:Databases
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• v.31 no.2
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• pp.195-204
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• 2004

The Semantic Web is proposed as the next generation Web technology. In the environment of the Semantic Web, resources are related with each other semantically and computers can process this information easily. The Resource Description Framework (RDF) supports this semantic relationship. RDF is the data model for describing metadata of the Web resources. To establish and develop the Semantic Web, methods for managing RDF data efficiently are the most important. So, in this research, we propose methods for storing and querying RDF data using an XML database system. Using an XML database system, XML data, main data of the Semantic Web, and RDF data, the metadata of XML data, can be managed in the same storage and by the same mechanism efficiently. In addition, we propose an efficient data retrieval method and several techniques to improve the system performance. Our query processing technique performs better than an existing system.

• Journal of the Korea Society of Computer and Information
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• v.23 no.10
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• pp.33-43
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• 2018

In this paper, we propose a method to automatically generate the description of an RDF graph structure. The description is expressed in Shape Expression Language (ShEx), which is developed by W3C and provides the syntax for describing the structure of RDF data. The RDF graphs to which this method can be applied are limited to those generated by the direct mapping, which is an algorithm for transforming relational data into RDF by W3C. A relational database consists of its schema including integrity constraints and its instance data. While the instance data can have been published in RDF by some standard methods such as the direct mapping, the translation of the schema has been missing so far. Unlike the users on relational databases, the ones on RDF datasets were forced to write repeated vague SPARQL queries over the datasets to acquire the exact results. This is because the schema for RDF data has not been provided to the users. The ShEx documents generated by our method can be referred as the schema on writing SPARQL queries. They also can validate data on RDF graph update operations with ShEx validators. In other words, they can work as the integrity constraints in relational databases.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.557-560
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• 2005

Production, utilization and related regulation of refuse derived fuel in Korea have been discussed in this paper. Also, the expected future of RDF has been discussed. Although the interest about RDF has been increased continuously , there are many things that must be solved for the development of RDF industry. Compared with other developed country, inadequacy of regulation about RDF and the lack of possible utilization facility make the limitation for the development of RDF industry.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.560-562
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• 2003

시멘틱 웹상에서는 정보 리소스들이 서로 의미적으로 연결되어. 이를 컴퓨터가 처리할 수 있다. Resource Description Framework (RDF)는 이런 의미적 연결성을 제공한다. 시멘틱 웹이 발전하기 위해서는 RDF 데이터를 효율적으로 관리하기 위한 방법이 매우 중요하다. 본 논문에서는 RDF 데이터를 XML 데이터베이스 시스템에 저장하고 이를 검색하는 기법을 제안한다 XML 데이터베이스 시스템을 사용함으로써 XML 데이터와 RDF 데이터를 통합적이고 효율적으로 관리할 수 있다. 또한. 효율적인 검색 방법과 성능을 향상시킬 수 있는 방법들을 제안하고 있다. 논문에서 제안한 질의 처리 기법은 기존 연구 보다 나은 성능을 보여준다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.07a
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• pp.195-197
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• 2016

시멘틱웹을 구축하는 표준언어인 RDF (Resource Description Framework)는 언어의 그래프 기반 특성으로 인해 일반적인 방식들로는 효과적인 저장과 추출이 어렵다. 더욱이 대용량 RDF 데이터의 저장과 추출에는 성능문제가 더욱 커지므로 많은 연구들이 이루어지고 있다. 본 논문에서는 SPARQL을 지원하면서 RDF 파일들을 효과적으로 저장하고 검색할 수 있는 저장방식에 대해 연구한 결과를 제시한다. RDF 데이터를 전처리를 통해 RDF의 트리플(주어:subject, 술어:property, 목적어:Object)에서 중복되는 주어(S)나 목적어(O)를 묶고, 사용자가 SPARQL 형식으로 검색했을 때 이용자가 주어부분을 변수로 두었는지 아니면 서술어 부분을 변수로 두어 찾는지에 따라 검색어와 유사한 단어 클러스터를 찾아준다. 동일 단어에 대해 여러 번 검색되던 부분을 한 번 검색으로 처리할 수 있기 때문에 효율이 높아진다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.187.1-187.1
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• 2011

RDF(Refuse-Derived Fuel) is a fuel of pelletized form made of combustible solid wastes and can not only be used as alternative energy to fossil fuel but also solve troubles in thermal uses of incinerator. As the first stage for obtaining elementary data required to develop criteria of raw materials appropriate to RDF combustion facilities actively spread recently in Korea, preliminary experiments were conducted on CO, SOx, NOx and HCl production and reduction characteristics in combustion of RDF. RDF samples weighing 2~3 g per a sample were manufactured in a lab-scale way and combustion tests of RDF were carried out in electric furnace with quartz tube of 50 mm inside diameter.

• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.137-141
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• 2001

The behavior of Cl is important to prevent HCl exhausted by incineration of RDF. Because RDF is composed of municipal wastes, its calorific value is very various. Thus components of RDF are to be analyzed and elemental analyze and calorific value are to be done. And in order to find the behavior of Cl during RDF combustion, Cl included in exhaust gas and ash is captured and analyzed. RDF which made by municipal and $Ca(OH)_2$ with regular ratio(Ca/0.5Cl) is incinerated in fluidized bed combustor. Cl included in exhaust gas and fly ash is captured and analyzed. Finally the change of Cl concentration included in exhaust gas and ash is analyzed and the behavior of Cl is investigated.