• Proceedings of the Korean Information Science Society Conference
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• 2001.04a
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• pp.667-669
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• 2001

최근 컴포넌트 사용과 컴포넌트 기반 개발 방법론을 이용한 전사적 자원 관리(ERP) 시스템과 정보 관리 시스템(EIS) 개발이 급속히 성장하고 있다. 그 시스템을 구성하는 엔티티 컴포넌트는 데이터베이스 질의 처리를 통해 자료의 영속성 처리를 한다. 그러나, 컴포넌트가 복잡한 질의 처리를 통해서 영속성을 유지해야 하는 경우는 데이터베이스간의 질의 처리가 호환되지 않는 문제점과 그를 해결하기 위해 모든 데이터베이스와의 연동을 지원하기에는 어려운 점을 가지고 있다. 엔티티 컴포넌트에서 각 데이터베이스 질의 연산을 추상 클래스 정의하고 이 추상 클래스와 엔티티 빈 간의 종속성 제거하고 이것을 통한 EJB 기반 엔티티 컴포넌트의 커스터마이제이션을 제시한다.

• Journal of the Korea Society of Computer and Information
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• v.13 no.1
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• pp.65-73
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• 2008

The telematics data management deals with queries on stream data coming from moving cars. So the stream DBMS should process the large amount of data stream in real-time. In this article, previous research projects are analyzed in the aspects of query processing. And a hybrid model is introduced where query preprocessor is used to process all types of queries in one singe system. Decreasing cost and rapidly increasing Performance of devices may guarantee the utmost parallelism of the hybrid system. As a result, various types of stream DBMS queries could be processed in a uniform and efficient way in a single system.

• Journal of KIISE:Databases
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• v.33 no.5
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• pp.551-562
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• 2006

XML query caching for XML database-backed Web applications began to be investigated recently. Despite its practical significance, efficiency of the storage schemes for cached query results has not been addressed. In this paper, we deal with the storage schemes for XML query cache. A fundamental problem that needs to be considered in designing an efficient storage structure for XML query cache is that there exist performance tradeoffs between the two major types of operations on a cached query result. The two are (1) retrieving the whole of it to return the query result and (2) updating just a small portion of it for its incremental refresh against the updates done to its source. We propose eight different storage schemes for XML query cache, which are categorized into three groups: (1) the schemes based on the plain text file, (2) the schemes based on the persistent DOM (PDOM) file, and (3) a scheme employing an RDBMS. We implemented all of them, and compared their performance with each other. We also compared our proposal with a storage scheme based on a current state-of-the-art XML storage scheme, showing that ours is more efficient.

• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.2
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• pp.67-79
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• 1998

Most GIS applications are read-intensive on a large number of spatial objects and when the spatial objects are composite objects, the contained objects within the composite objects are also accessed. In GIS applications, creation, deletion, and update operations on spatial objects occur very rarely, but once they occur they deal with a large number of spatial objects. This paper proposes the concept of the multi-level pre-fetch query to retrieve a large number of spatial objects efficiently, and the functionality of the deferred-flush on the newly created persistent objects into the database with the optimal performance, and presents the design and implementation details of those ideas into an object-oriented DBMS BADA-III while considering these characteristics of GIS applications. The multi-level pre-fetch query retrieves the objects that satisfy the query and the objects that are contained within the objects up to the level specified by users, and registers the retrieved objects on the client cache. The deferred-flush flushes a large number of composite objects that are created by the application with a minimal overhead of the server and a minimal number of communications between the client and the server. These two functionality are suitable for the applications that search or create a large number of composite objects like GIS applications.

• Korean Journal of Social Welfare
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• v.60 no.1
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• pp.5-27
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• 2008

Purpose: This study aims to better understand the quality of life (QOL) for Korean breast and gynecological cancer survivors by examining the differences in multi-dimensional QOL outcomes according to stage of cancer survivorship. Methods: To identify the multiple dimensions of health status and psychosocial outcomes, three standardized QOL and psychological distress measures were administered to 110 Korean breast and gynecological cancer survivors. These participants were divided into three groups based on the stage of cancer survivorship. Results: Analyses of covariance revealed that once important confounders were controlled for, QOL outcomes were partially different depending on the stage of cancer survivorship. Results for SF-36 measure showed significant differences between acute and long-term survival stages, indicating that QOL for cancer survivors had gradually improved in the physical domain. However, there were no significant group differences in the psychological domain of SF-36. Additionally, QOL-CS and BSI-18 measures did not show significant QOL differences according to the stage of cancer survivorship. Conclusions: Evidence that, for Korean survivors, QOL outcomes differ according to the stage of cancer survivorship serves as a rationale for developing discriminatory strategies and interventions that take into account survival stage.