• 인터넷정보학회논문지
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• 제19권5호
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• pp.107-113
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• 2018

Object-oriented databases (OODBs) canbe used for many non-traditional database application areas such as computer-aided design, etc. Usually those application areas require advanced modeling power for expressing complicated relationships among data sets. OODBs have more distinguished features than the traditional relational database systems. One of the distinguished characteristics of OODBs is class hierarchy (also called inheritance hierarchy). A class hierarchy in an OODB means that a class can hand down the definitions of the class to the subclass of the class. In other words, a class is allowed to inherit the definitions of the class from the superclass. In this paper, we present performance evaluation metrics for class hierarchy in OODBs from a concurrency control perspective. The proposed performance metrics are developed to determine which concurrency control scheme in OODBs can be used for a given class hierarchy. In this study, in order to develop performance metrics, we use class hierarchy structure (both of single inheritance and multiple inheritance), and data access frequency for each class. The proposed performance metrics will be also used to compare performance evaluation for various concurrency control techniques.

• 한국컴퓨터정보학회논문지
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• 제16권11호
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• pp.25-34
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• 2011

본 논문에서는 UML(Unified Modeling Language)을 토대로 유스케이스(use case) 중심의 객체지향 분석 설계 방법론을 기반으로 한, 관계형 데이터베이스 통합 설계방법론에 대하여 다룬다. 본 통합 설계방법론에서 사용하는 개념모델은 비즈니스 프로화일(business profile)에 기반을 두고 있으며, 6단계로 구성되어 있다. 첫 번째 단계에서는 비즈니스 유스케이스(business use case)가 식별되어 마크로액티비티 다이어그램(macroactivity diagram)으로 표현되고, 두 번째 단계에서 마크로액티비티 다이어그램은 비즈니스 객체(business object)와 비즈니스 객체흐름(business object flow) 그리고 비즈니스 사용자책임(business worker's responsibilities)을 이용하여 상세 비즈니스 활동다이어그램(detailed business activity diagram)으로 변환된다. 세 번째 단계에서는 상세 비즈니스 활동다이어그램을 기반으로 시스템 전체의 정적 구조를 설명하는 비즈니스 클래스다이어그램(business class diagram)으로 변환된다. 네 번째 단계에서 비즈니스 클래스다이어그램은 대응하는 관계형 데이터베이스 초기 개념모델을 대표하는 클래스다이어그램으로 변환된다. 다섯 번째 단계에서 클래스다이어그램에 일반화와 특수화, 역할과 활동, 클래스 추가 그리고 중복 연관에 따른 추가적인 변환이 이루어지고, 마지막으로 관계형 데이터베이스 스키마로 변환이 이루어지게 된다. 본 논문에서 제시하는 방법론을 적용함으로써, 객체지향 분석 설계 방법론과 관계형 데이터베이스 설계방법론 사이에 유기적 연결이 이루어지게 되어, 객체지향 분석 설계 방법론 관계형 데이터베이스설계 방법론을 통합적으로 다룰 수 있게 된다. 이에따라 관계형 데이터베이스 기반의소프트웨어 시스템에 대한 객체지향 방식의 일관된 그리고 통합된 구축방안이 제공된다. 사례 연구로 제안한 통합 설계 방법론을 비자발급시스템에 대하여 적용한다.

• 한국정보처리학회논문지
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• 제6권3호
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• pp.553-561
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• 1999

The facility of schema evolution is necessary in object-oriented database applications. There exist several versions of schema and instances created under different versions of the schema concurrently in the database. This base proposes a mechanism for supporting accessing instances regardless of versions of the schema in schema evolution environments in object oriented databases. There is trade-off between the flexibility of schema modification operations and the system overhead for supporting such schema modifications. Access handling routines are provided to the undefined attributes in each version of the class. Access handling routines are also defined for each pair of semantics rather than defining backdate/update functions for each pair of versions of a class. Thus, this mechanism supports the change of semantics with reduced user and system overhead.

• 한국정밀공학회지
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• 제15권2호
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• pp.107-113
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• 1998

Grinding operation has difficulty in satisfying the qualitative knowledge based on the skilful expert as well as the quantitative data for all user. Design of grinding database based on the frame-based model is more effective method for utilizing the empirical and qualitative knowledge. In this paper. basic strategy to develop the grinding database by taking frame-based model, which is strongly dependent upon experience and intuition, is described. Grinding database based on the frame based model for designing the interaction and inference among the slots is accomplised by the object-oriented paradigm system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.275-277
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• 2003

This paper deals with Object-oriented Database(OODB) which is designed for power system analysis, and describes load flow analysis using OODB. Database management systems are widely used and achieve high reliability of data management in the engineering fields. However conventional database systems, relational database system, have disadvantages in application to power system analysis. This paper presents advantages of OODB for modeling complex data of a power system analysis. The OODB supports data modeling requirements of GUI applications and the performance is well acceptable for GUI applications.

• 경영과학
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• 제11권2호
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• pp.43-63
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• 1994

A new model management framework is proposed to accommodate wide-spreading algebraic modeling languages (AMLs), and to facilitate a full range of model manipulation functions. To incorporate different modeling conventions of the leading AMLs (AMPL, GAMS, and SML) homogeneously, generic model concepts are introduced as a conceptual basis and are embodied by the structural and operational constructs of an Object-Oriented Database Management System(ODBMS), enabling the framework to consolidate components of DSSs(database, modelbase, and associated solvers) in a single formalism effectively. Empowered by a database query language, the new model management framework can provide uniform model management commands to models represented in different AMLs, and effectively facilitate integration of the DSS components. A prototype system of the framework has been developed on a commercial ODBMS, ObjectStore, and a C++ programming language.

• 한국정보처리학회논문지
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• 제4권2호
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• pp.325-337
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• 1997

본 논문은 객체지향 패러다임에 입각한 데이터베이스 시스템의 기본적인 개념과 필요 요건을 제시하고 이에 부응하는 객체지향 데이터베이스 시스템의 개괄적 설계를 보인다. 이 시스텀은 C++에 기초하여 크게 세개의 개층으로 구성 된다. 최하층은 저장시스템(storage system)으로 화일 입출력을 수행하고 중간층은 트랜잭션 관리, 시크마관리, 주기억장치에서의 버퍼관리 등 사용자 인터페이스를 제외한 여러 기능을 담당한다.최상위층은 사용자인터페이스를 위하여 설계되어 그래픽 사용자 인터페이스 (graphical user interface), 전처리기(prepro-cessor), 인터프리터 등 여러관련 기능을 제공할 뿐만 아니라 객체지향의 여러 특성을 위해 확정된 SQL을 지원하하도록 한다.

• Asia pacific journal of information systems
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• 제8권3호
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• pp.21-36
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• 1998

Group collaborative systems are recently emerging to support a group of users engaged in common tasks such as group decision making, engineering design, or collaborative writing. Simultaneously, as communications networks and distributed database systems become core underlying architecture of the organization, the need of collaborative systems are gaining more attentions from industry. In such collaborative systems, as the shared objects may evolve constantly or change for operational purposes, providing the users with synchronized and consistent views of the shared object and maintaining the consistency between shared object and replicated objects are important to improve the overall productivity. This paper provides an change management framework for the group collaborative systems to facilitate managing dependency relationships between shared objects and dependents, and coordinating change and propagation activities in distributed computing environments. Specifically, the framework adopts an object-oriented database paradigm and presents several object constructs capturing dependency management and change notification mechanisms. And the proposed framework accommodates both persistent dependents such as replicated data and transient dependents such as various user views in a single formalism. A prototype system is developed on a commercial object-oriented database management system called OBJECTSTORE using the C++ programming language.

• 전자공학회논문지B
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• 제30B권4호
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• pp.11-20
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• 1993

In the new database applications such as office information systems, CAD/CAM, and AI, it is required to support not only fixed Is-A and Part-Of relationships but also various user-defined dynamic relationships including complicate constraints. However, existing object-oriented systems have many weaknesses in managing those complex relationships. This paper presents the Object-Oriented Relationship data Model (OORM) which is designed to provide facilities for modeling complex relationships into object oriented databases using abstraction concept. In the model, various integrity and consistency constraints related to the relationships can be also represented. And this paper presents a query language, ORSQL(Object Relationship SQL). ORSQL is a nonprocedural query language having similiar syntax to the standard SQL and supporting OORM's operations.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.1016-1021
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• 1989

In this paper, we introduce a recursively-defined natural join operation as well as well-known object composition operations (union, intersection) for composing CAD database objects. Then, we will discuss how to realize these operations by the message passing computing mechanism. Next, we will discuss what kind of behaviours (methods) are preserved under our natural join operations. Finally, we investigate mathematical properties about the relationships among several object composition operations (natural join, union and intersection).