• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.4B
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• pp.323-338
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• 2003

The main memory database systems (MMDBMS) efficiently supports various database applications that require high performance since it employs main memory rather than disk as a primary storage. Recently, it has been increased needs that have the fast data processing as well as the efficient modeling of application requiring for a complicated structure, and conformity to applications that need the strict dta consistency. In MMDBMS, because all the data is located in the main memory, it can support the usable expression methods of data satisfying their needs without performance overhead. The method has the operation to manipulate the data and the constraint such as referential integrity in more detail. The data model consists of this methods is an essential component to decide the expression power of DBMS. In this paper, we discuss about various requests to provide the communication services and propose the data model that support it. The mainly discussed issues are 1) definition of the relationship between tables using the pointer, 2) navigation of the data using the relationship, 3) support of the referential integrity for pointer, 4) support of the uniform processing time for the join, 5) support of the object-oriented concepts, and 6) sharing of an index on multi-tables. We discuss the pointer-based data model that designed to include these issues to efficiently support complication environments.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.53-63
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• 2011

Many techniques have been proposed to store and query XML data efficiently. One way achieving this goal is using relational database by transforming XML data into relational format. It is important to transform schema to preserve the content, the structure and the constraints of the semantics information of the XML document. Especially, key constraints are an important part of database theory. Therefore, the proposal technique has considered the semantics of XML as expressed by primary keys and foreign keys. And, the proposal technique can preserve not only XML data constraints but also the content and the structure and the semantics of XML data thru transformation process. Transforming information is the content and the structure of the document(the parent-child relationship), the functional dependencies, semantics of the document as captured by XML key and keyref constraints. Because of XML schema transformation ensures that preserving semantic constraints, the advantages of these transformation techniques do not need to use the stored procedure or trigger which these data ensures data integrity in the relational database. In this paper, there is not chosen the ID/IDREF key which supported in DTD, the inheritance relationship, the implicit referential integrity.

• The Journal of Information Technology and Database
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• v.6 no.1
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• pp.1-13
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• 1999

The modeling components in the object-oriented paradigm are based on the object, not the structured function or procedure. That is, in the past, when one wanted to solve problems, he would describe the solution procedure. However, the object-oriented paradigm includes the concepts that solve problems through interaction between objects. The object-oriented model is constructed by describing the relationship between object to represent the real world. As in object-oriented model the relationships between objects increase, the control of objects caused by their insertions, deletions, and modifications comes to be very complex and difficult. Because the loss of the referential integrity happens and the object reusability is reduced. For these reasons, the necessity of the control of objects and the visualization of the relationships between them is required. In order that we design a database necessary to implement Object Browser that has functionalities to visualize Java objects and to perform the query processing in Java object modeling, in this paper we show the processes for EER modeling on Java object and its transformation into relational database schema. In addition we implement Java Object Parser that parses Java object and inserts the parsed results into the implemented database.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04b
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• pp.40-42
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• 2002

데이터 웨어하우스는 물리적으로 여러 사이트에 위치한 분산된 데이터 소스로부터 추출한 온라인 분석 정보를 유지하는 실체 뷰 의 집합으로 구성된다. 따라서 데이터 소스에 변경 사항이 발생하면 데이터 웨어하우스와 일관성을 유지하기 위해 뷰에도 그 변경사항을 반영하는 뷰 관리가 필요하다 동시에 변경되는 여러 데이터 소스와 뷰의 상태 사이에 일관성을 보장하기 위해서는 각 소스의 변경 사항을 순서대로 뷰에 반영해야 한다. 이때 각 소스의 변경 사항을 뷰 정의와 관련된 다른 소스들과 조인을 수행해야 하는 등 뷰 갱신을 위해 많은 비용이 소요된다. 이러한 뷰 갱신 비용을 줄이는 방법중의 하나로 병렬처리 기법을 활용하는 연구가 시도되고 있다. 따라서 이 논문에서는 뷰의 일관성을 보장하기 위해 수행해야 하는 서브질의론 병렬로 처리하는 알고리즘을 제시하였다. 이 방법에서는 서브질의의 조인 연산들을 소스 렐레이션들 간의 참조 무결성 제약 조건을 이용하여 병렬로 처리한다. 질의의 조인 처리를 병렬화 하기 위해 소스 릴레이션간의 참조 무결성 제약조건의 툭송울 이용하여, 여러 릴레이션을 참조하는 릴레이션에서 발생하는 변경 사항에 대해 참조하는 릴레이션의 수만큼 병렬로 조인 연산을 수행하는 알고리즘을 제시하였다. 이렇게 함으로써 여러 소스 릴레이션의 조인으로 구성된 실체 뷰를 갱신하는 시간을 크게 단축하여 효율적으로 뷰를 관리하도록 하였으며, 소스의 증가에 따른 뷰 갱신 시간의 증가를 줄일 수 있도록 하였다.

• Journal of Internet Computing and Services
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• v.10 no.2
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• pp.99-116
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• 2009

For the mapping of two dimensional table structures of relational databases to the hierarchical XML documents, we apply the foreign key relationships of relational databases. In other words, the primary key of another table referenced by a foreign key of one tuple is mapped to the parent of the foreign key. Then XML hierarchies with order are expressed. In addition, the XML view file generated by the foreign key mappings shows side effects in the case of the relational database update for the satisfaction of referential integrity constraint in the foreign key. Thus, by inferring the foreign key roles at the generation of XML hierarchies, we can anticipate where the side effects occur in the hierarchies. We keep the XML view files up-to-date by reflecting the side effects to the XML files at the update of the underlying relational databases.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.11
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• pp.125-134
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• 2018

This study examines Dalibor Vesely's theoretical proposition of communicative space and tries to develop it through a review of the contemporary architectural case. Vesely poses a critical question about communication: how do the situational conditions of our everyday life and the spatial characteristics of the natural world in which we live communicate through representation. He emphasizes the spatial and situational conditions and the role of representation in communication, arguing that architecture should create the formation of communicative space to restore its primary role as the corporeal foundation of culture. This study thus focuses on one of the critical concepts of his theory: "the communicative movement," which is, according to him, ontological and situational because it animates and transforms human circumstances as a whole. Further, it pursues some practical knowledge of creating the communicative space, by examining the design theory and practice of Zaha Hadid, who thematizes communication and movement in her architectural approach. This study analyses the different levels of representation and modes of movement in her architectural space to reveal the possibilities and limits of its communicative roles. We will find that the representation of Hadid's architectural space is not the formal representation of reality, but a mathematical and projective representation of abstract concepts. Despite its apparent aesthetic consistency, the inward and self-referential relation between the individual elements of the architectural space reveals its limit for the communicative space.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.3
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• pp.161-172
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• 2013

Metadata registry (MDR) is the international standard, developed by ISO/IEC for exchange and sharing data between databases. Many MDR systems are used in diverse domains such as medical service, bibliography, environment for sharing and integrating data. However, those systems have different physical structures individually because the MDR standard defines only the metamodel for registering and storing metadata. It causes heterogeneity between the system structures and requires additional cost to maintain interoperability. ISO/IEC 13249-8 Metadata Registry Access (MRA) is developing as an international standard to provide a consistent access facility to data stored in different metadata registries. However, MRA does not consider the relationships between the concepts (classes) defined in the MDR specification. It causes that incorrect query results returned from MDR systems. It also requires additional cost of modeling and rewriting queries to reflect each physical model. Therefore, this paper suggests eMRA which considers the relationships between the concepts in MDR. The comparative evaluations are described to show the advantages of eMRA. eMRA has superior performance in query modeling and referential integrity than MRA defined by the relationship between the concept of MDR.