• Proceedings of the Korea Information Processing Society Conference
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• 2004.11a
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• pp.55-58
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• 2004

XML 의 중요성이 부각 되면서 XML 데이터의 효율적 관리 기법에 관한 연구가 활발히 수행되고 있다. XML 질의의 표준화 작업도 활발히 이루어져 현재 XQuery가 유력한 표준으로 부각되었다. 그러나 XQuery 등이 완전한 XML 질의어가 되기 위해서는 변경 연산을 제공해야 하는데 XML 변경어의 표준화 작업이나 XML 변경 처리 기법에 대한 연구는 아직 미미한 실정이다. 본 논문에서는 e-Business 등 XML 데이터베이스 기반 웹 응용의 효율적 지원을 위한 XML 문서 갱신에 대한 기법을 다룬다. XML 문서의 효율적 갱신을 위한 RN(RmdEid, NextChildEid) 번호 체계, R(RmdEid) 번호 체계 을 제시한다. 어떤 XML 번호 체계를 사용하여 XML 문서를 저장하는 가는 XML 문서의 갱신 연산에 중용한 영향을 미친다. 이들 번호 체계들은 데이터베이스내의 테이블 스키마의 차이점으로 구분한 것이다. 이들 번호체계 각각에 대하여 XML 데이터베이스 시스템을 구현하여 이들 기능의 성능 및 공간 부담을 평가한 결과를 기술한다.

• Journal of Korea Multimedia Society
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• v.6 no.3
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• pp.397-408
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• 2003

Existing indexing mechanisms of XML data using numbering scheme have a drawback of rebuilding the entire index structure when insertion, deletion, and update occurs on the data. We propose a new indexing mechanism based on split blocks to cope with this problem. The XML data are split into blocks, where there exists at most a relationship between two blocks, and numbering scheme is applied to each block. This mechanism reduces the overhead of rebuilding index structures when insertion, deletion, and update occurs on the data. We also propose two algorithms, Parent-Child Block Merge Algorithm and Ancestor-Descendent Algorithm which retrieve the relationship between two entities in the XML hierarchy using this indexing mechanism. We also propose a mechanism in which the identifier of a block has the information of its Parents' block to expedite retrieval process of the ancestor-descendent relationship and also propose two algorithms. Parent-Child Block Merge Algorithm and Ancestor-Descendent Algorithm using this indexing mechanism.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.82-84
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• 2002

XML은 자기 서술적인 표현 언어라는 중요한 장점을 가지고 있기 때문에 인터넷 관련 응용들에서 정보의 표현 및 문서 교환의 표준으로 빠른 속도로 자리잡아 가고 있다. 본 논문에서는 SQL에 XPath 표현 중 일부를 추가하여 SQL을 확장함으로써 XML 문서에 대한 질의를 가능하게 하였고, 또한 SQL의 CRUD(Create, Read. Update, Delete) 기능을 그대로 사용함으로써 XML 문서의 변경이 가능한 XML 질의를 위한 새롭게 확장된 SQL을 제안하였다. 그리고 폭 넓게 사용되고 있는 ORDBMS 환경에서 XML 색인 정보를 자동 생성 관리하는 XML 저장 관리기 및 확장된 SQL 처리기를 설계하고 구현하였다. 본 논문에서 제안하는 확장된 SQL 처리기는 XML 원문 자체의 보관을 원칙으로 하여 완벽한 문서 복구 등에 따르는 부담을 제거하였고, XML 저장 문서에 대한 원본성 및 무결성을 쉽게 유지할 수 있도록 하였으며, 색인 정보를 자동 생성 관리함으로써 파일 처리 시간과 XML 트리 운행 시간 및 XPath 파싱 처리 시간을 줄였다. 또한, “path”라는 키워드를 추가로 관리함으로써 ORDBMS 환경에서 XML 질의를 위한 SQL 변환 과정에서 PATH의 깊이 만큼 조인이 중첩되는 문제를 배제하여 조인이 발생할 가능성을 줄이는 방법을 제시하였다.

• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.83-91
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• 2011

The roadmap DB update for unknown roads is a very important factor for car navigation systems. In this paper, we propose a cloud computing based roadmap generation method for use between heterogeneous navigation system for unknown roads. While the drivers drive on unknown roads, the proposed method extracts the road attribute information, and then generates the metadata in an XML format that is available for the heterogeneous navigation systems in a cloud environment. The metadata is proposed to be used as a replacement for conventional proprietary roadmap formats which used by roadmap providers, which is efficient for heterogeneous navigation system providers in a cloud computing environment. Then, this metadata is provided to the roadmap DB providers through the cloud computing interfaces. With the proposed method, the roadmap DB providers update the own roadmap DB for navigation systems in real time. Therefore, the proposed method can reduce the costs of an actual traveling test and the maintenance for the roadmap DB provides. Thus, the cloud-oriented road map generation method can more efficiently update the unknown road information.

• The KIPS Transactions:PartD
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• v.11D no.7 s.96
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• pp.1367-1374
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• 2004

For sharing XML data by many users, a way of concurrency and access control is required for isolating update actions such as inserting and deleting subtrees. Exisiting locking mechanisms as 2PL or MGL suffer low concurrency when applied to tree structures. In this paper, list data subtrees model is proposed based on the semantics expressed in DTD. In this model, tree updating actions such as inserting and deleting subtrees are considered only for the repetitive parts of XML trees. The proposed model guarantees that the result XML tree after applying a tree updating action is always valid, even when multiple users access the tree at the same time. Also, a new locking mechanism called list lock-ing protocol is proposed. The new locking protocol is expected to show better accessility with less number of locking objects compared to the Helmer's OO2PL model. Since update actions on a shared XML tree usually applied to the repetitive parts of the tree, the proposed model is expected to provide a useful way for efficient data sharing when combined with previous locking methods on terminal node data.

• Journal of Life Science
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• v.12 no.4
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• pp.383-391
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• 2002

The difficulties in dealing with the Bioinformatics data come more from its idiosyncrasies than from its quantity Currently researchers need to an easy method for data exchange, manage, update. In order to integrate and manage all kinds of biological data, it is reasonable to adopt XML as standard tool since XML is independent of operating system, programming language and hardware platform. Although XML in Bioinformatics has been used widely as a standard notation abroad, however it is the beginning step in the domestic research. This article reviews a basic concept of XML and how to apply XML modeling in Bioinformatics. In addition we present XML applications for genomic sequences, structures and genetic network modeling.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.81-84
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• 2004

XML 문서는 관계형 테이블과는 달리 문서의 구조가 매우 복잡하고 불규칙하여 부분적인 정보를 최대한 활용하는 전문 검색이 일반적인 구조적 검색보다 더 중요한 역할을 한다. XML 문서는 계층이 있으므로 계층을 사용하는 전문 검색 연산은 계층을 제공함으로써 검색 공간을 줄여서 검색의 정확성과 효율성을 훨씬 더 높일 수 있다. 전문 검색 연산을 효과적으로 지원하기 위한 방법으로는 역인덱스를 (inverted index) 사용하는 것이 가장 일반적인 방법이다. 지금까지의 전문 검색을 위한 XML 문서의 구조 정보를 표현, 저장하는 방법들은 문서의 내용이 변경되지 않는 정적 문서(static documents)만을 고려하여 왔다. 이 방법들은 문서가 동적으로 변화할 경우 저장된 문서의 구조 정보 중에서 많은 부분을 다시 표현해야 하는 비효율적인 면이 있다. 본 논문은 XML 문서의 동적인 변화를 지원하면서 동시에 복잡한 XML 전문 검색을 지원하기 위한 방법으로 경로 스트링을 사용하는 효율적인 역 인덱스 구축 기법을 제안하고 제안하는 방법이 복잡한 문서의 검색과 문서의 동적인 변화를 효율적으로 검색할 수 있음을 보인다.

• Journal of the Korea Computer Industry Society
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• v.5 no.1
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• pp.87-100
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• 2004

XML has recently considered as a new standard for data presentation and exchange on the web, many researches are on going to develop applications and index mechanism to store and retrieve XML documents efficiently. In this paper, design a Main-Memory based XML storage system for efficient management of XML document. And propose structured retrieval of XML document tree which reduce the traverse of XML document tree using element type information included user queries. Proposed indexing mechanism has flexibilities for dynamic data update. Finally, for query processing of XML document include Link information, design a index structure of table type link information on observing XLink standards.

• Journal of KIISE:Databases
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• v.30 no.3
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• pp.252-272
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• 2003

The view mechanism provides users with appropriate portions of database through data filtering and integration. In the Web era where information proliferates, the view concept is also useful for XML, a future standard for data exchange on the Web. This paper proposes a method of implementing XML views called XML view indexing, whereby XML view xv is represented as an XML view index(XVI) which is a structure containing the identifiers of xv's underlying XML elements as well as the information on xv. Since XVI for xv stores just the identifiers of the XML elements but not the elements themselves, when a user requests to retrieve xv, its XVI should be materialized against xv's underlying XML documents. Also an efficient algorithm to incrementally maintain consistency of XVI given a update of xv's underlying XML documents is required. This paper proposes and implements data structures and algorithms for XML view indexing. The performance experiments on XML view indexing reveal that it outperforms view recomputation for repeated accesses to the view, and requires as much as about 30 times less storage space compared to XML view materialization though the latter takes less time for repeated accesses to the view due to no need of materialization.

• Journal of KIISE:Databases
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• v.31 no.1
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• pp.48-60
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• 2004

XML documents consist of elements that are basic units of information. When the structure of XML documents is changed dynamically, we need to update structure information efficiently without changing the information of the index structure for fast retrieval. In this paper, we propose a dynamic indexing model scheme that updates the index structure in real time as the structure of XML documents is changed by insertion and deletion of elements. Our dynamic indexing model consists of a structure information representation method and a dynamic index structure. The structure information representation method supports various types of structure retrievals. Our dynamic index structure processes various structural queries efficiently. We show through various experiments that our method outperforms existing ones in processing various types of queries such as content based queries, structural queries and hybrid queries.