• Journal of KIISE:Databases
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• v.31 no.5
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• pp.445-456
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• 2004

The database schema is assumed to be stable enough to remain valid even as the modeled environment changes. However, in practice. data models are not nearly as stable as commonly assumed by the database designers. Even though a rich set of schema change operations is provided in current database systems, the users suffer from the problem that schema change usually impacts existing application programs that have been written against the schema. In this paper, we are exploring the possible solutions to overcome this problem of impacts on the application programs. We believe that for continued support of the existing programs on the old schema, the old schema should continue to allow updates and queries, as before. Furthermore, its associated data has to be kept up-to-date. We call this the program independency property of schema change tools. For this property. we devise so-called program independency schema evolution (PISE) methodology. For each of the set of schema change operations in the relational schemas, the sketch of the additional algorithms due to the PISE compliance is presented in order to prove the comprehensiveness and soundness of our PISE methodology.

• Journal of Korean Society of Rural Planning
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• v.11 no.2 s.27
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• pp.43-49
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• 2005

As information has been brought to public attention, information storage as well as information usability has been important. Rural information is produced in many areas and institutions. However, it is difficult to use rural information comprehensively. Since formats for management are various, it is difficult to have unified frame. In this research, a schema of database fer integrating rural data is designed to improve usability using dimensional modeling. First of all, rural data are analyzed for designing integrated rural database schema. Rural data used are 'National Agricultural Statistics' and 'Gun annual statistical report'. Analysis shows that there are three considerations; administrative district, time-dependency and classification of data. Considering these three requisite, we designed database schema using dimensional modeling. The reason of using dimensional modeling is to improve usability and effectiveness. If the database was designed using ER modeling, many tables have to be joined every searching time. Separately from integrated rural database schema, user's database schema is designed considering usability. Through user's database, users can modify data or generate new data and save these processes. These make it possible to use generated data repeatedly. We evaluate usability, contribution, and effectiveness of data manipulation on the integrated rural database. We propose an integrated rural database structure improving the accessibility and usability of rural data and information and verified the data model based on a practical example.

• Journal of National Security and Military Science
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• s.1
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• pp.269-310
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• 2003

AS Extensible Markup Language(XML) is emerging as the data format of the Internet era, there are increasing needs to efficiently transform between database and XML documents. In this paper, we propose a schema transformation method from relational database to XML database. To transform the schema, we represent input schema as Entity-Relationship diagram. Entity-Relationship model translator scans the input Entity-Relationship diagram using BFS (breadth First Search) and translates the diagram into hierarchical structure model. The XML Schema generator produces XML Scema code using the transformed hierarchical structure model. The proposed method has a merit that having reusability facility of XML Schema property in comparison with existing researches.

• The Journal of Information Technology and Database
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• v.8 no.1
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• pp.105-116
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• 2001

XML is a standard markup language for exchange and storage of formed or well-formed information in World Wide Web. Because the source data of XML message for exchange of information in World Wide Web is stored in legacy database, it is necessary for the easy connection between XML application and database system. In Oracle8i, 9i, Informix and SQL2000, DBMS vendors make upgrade to DBMS for using XML. This method of upgrade between XML application and database system is Platform-dependent and DBMS-dependent. Also It is necessary for the method of the platform- and DBMS-independent connection between XML application and database system. The methods for the connection between XML DTD and RDB schema are studied for the easy connection between XML application and database system. But the study for the easy connection between XML DTD and ORDB schema is a little. For multimedia application, we use the extended DBMS from RDBMS. It is necessary for the study to the transformation from XML DTD to ORDB schema. In this paper, for easier connection between XML application and database system, we propose the method of the transformation from XML DTD to ORDB schema using Object Model.

• Journal of Internet Computing and Services
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• v.3 no.2
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• pp.39-56
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• 2002

In distributed computing environments, there are many database applications that should share data each other such as data warehousing and data mining with autonomy on local databases. The first step to such applications is the integration of heterogeneous database schema, but there is no accepted common data model for the integration and also are difficulties on the construction of integration program. In this paper, we use the XML Schema for the representation of common data model and exploit XSLT for reducing the programming difficulties. We define the schema integration operations and develop a methodology for the semi-automatic schema integration according to schema conflicts types. Our integration method has benefits on standardization, extendibility on schema integration process comparing to existing methodologies.

• Asia pacific journal of information systems
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• v.6 no.1
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• pp.165-194
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• 1996

Data distribution is one of the most important steps in distributed database design. This paper proposes a methodology for distributing database by using a relational schema as an input. A design support system called DBDD (Database Distribution Design) is implemented within the framework of this methodology. The methodology consists of three phases such as (i) schema analysis, (ii) fragmentation, and (iii) allocation. In the schema analysis phase, all the table names are acquired from a global relational schema. In the fragmentation phase, fragments are generated according to transaction retrieval patterns. Furthermore, DBDD enhances the design quality by allocating fragments in a progressive manner. A real-life case is illustrated to demonstrate the practical usefulness of the DBDD.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.2
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• pp.98-107
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• 2003

The purpose of this study is to propose the schema for process repository that overcomes the limitations of existing process repositories in which it is not easy to compare and analyze such the unstructured data as a process model. To achieve this goal, the previous studies on process repository are reviewed, the schema for process repository is designed, and the tables for relational database are created. For the validation of the schema presented in this paper, the process model stored in relational database is examed using SQL. The contributions of this study are as follows. First, the schema for process repository storing process models is designed and validated. Second, the process model created by the new schema and stored in relational database leads to improve the performance of process analysis.

• Journal of the Korean Society for information Management
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• v.19 no.2
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• pp.49-67
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• 2002

Nowadays an information exchange on XML such as B2B electronic commerce is spreading. Therefore the systematic and stable management mechanism for storing the exchanged information is needed. For this goal there are many research activities for connection between XML application and database. Accordingly, A unified modeling methodology need to store the XML file on the variety database. In this paper, we propose a unified design methodology for XML applications based on variety databases using UML. To this goal, first we introduce a XML modeling methodology to design W3C XML schema using UML and second we propose data modeling methodology for object-relational database schema, object oriented database an schema and relational database schema to store efficiently XML data in databases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1604-1609
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• 2004

We have to convert XML DTD into relational database schema for storing XML Document at relational database. Hybrid inlining algorithm are used for converting XML DTD to relational database schema. But this method have some problem. That is the relational database schema have N:N relationship are created according this method are not satisfied with third normal from. Therefore, We proposed Extended Hybrid inlining algorithm for solving this problem in this paper.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.301-304
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• 2002

Recently, database technologies have been used commonly. But, ordinary technologies aren't suitable to construct a complicated database such as a classical literature database or an archaeological relic's database. Because this kinds of data are semi-structured data that doesn't have regular structures, database schema can't be defined before databases. We have proposed DREAM model for semi-structured databases. In this model, a database consists of five elements and the model has operations similar to operation of set theory. And further we have introduced dynamic schema "shape" showing structure of each element. We have already realized a prototype of DBMS adopting DREAM model (DREAM DBMS) and constructing function of shapes. However, shape is imperfect to describe database structures because it can't explain nested structures of elements. In this paper, we will profuse a "shape graph"that is dynamic schema showing database structures more exactly and extend the DREAM DBMS. Further we will evaluate the performance of constructing function of shapes and shape graphs.