• Journal of KIISE:Databases
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• v.29 no.2
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• pp.110-118
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• 2002

This paper presents a 3-D graphic database system based on XML that supports content-based retrievals of 3-D images, Most of graphics application systems are currently centered around the processing of 2-D images and research works on 3-D graphics are mainly concerned about the visualization aspects of 3-D image. They do not support the semantic modeling of 3-D objects and their spatial relations. In our data model, 3-D images are represented as compositions of 3-D graphic objects with associated spatial relations. Complex 3-D objects are mode]ed using a set of primitive 3-D objects rather than the lines and polygons that are found in traditional graphic systems. This model supports content-based retrievals of scenes containing a particular object or those satisfying certain spatial relations among the objects contained in them. 3-D images are stored in the database as XML documents using 3DGML DTD that are developed for modeling 3-D graphic data. Finally, this paper describes some examples of query executed in our Web-based prototype database system.

• Journal of KIISE:Databases
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• v.27 no.1
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• pp.113-128
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• 2000

The adaptation of spatial view is to update materialized view objects when apatial view is redefined. There are tow kinds of adaptation : incremental updates and recomputation. The incremental update changes related view objects and it is more efficient than the recomputation which evaluates redefined view defining query because spatial view is defined by spatial query including high cost spatial operator. This paper proposes the several incremental update methods according to the types of changing the definition of a spatial view. There are two kinds of incremental view adaptation : the method of using only the existing view objects and the view derivation relationship between view objects and their sources. This incremental update is achieved by updating the current materialized view objects or by inserting new materialized view objects. Spatial view adapter is implemented and tested on top of the object oriented geographic information system. This paper evaluates performance between the recomputation and incremental update method through real data.

• Journal of IKEEE
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• v.7 no.2 s.13
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• pp.144-155
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• 2003

In this paper, a conceptual data model, called the UDM(Unified Data Model), to efficiently represent database structures related with object technology and complex structured data, is proposed. This model integrates major features of modern data models, such as E-R model, Semantic Object Model, and UML, especially from the viewpoint of database design. This model is basically a simplified, but extended version of the Object-Relationship Model, which was proposed to model complex structures of temporal-spatial multimedia data. This model incorporates some of the important semantic and structural information of modern database applications and it is designed to support all of the major logical database models, including relational, object-relational, object-oriented, and (semi-)structured databases. A special diagrammatic technique, called the UDD(Unified Data Diagram), is introduced as a tool for database design. Also, possible ways to derive logical views of data from this unified data model are presented. The proposed model can be utilized as a convenient and practical tool for conceptual database designs.