• Korean Management Science Review
• /
• v.11 no.3
• /
• pp.87-102
• /
• 1994

Conceptual database design is an important activity because the performance of a DBMS heavily depends on the proper design of the database, and view integration is one of the most important phases of conceptual database design. During this phase, the individual views designed by separate user groups are integrated into a global view for the entire system. After the view integration, a database schema must be validated before it becomes a stable product of the design. In this paper, a methodology for view integration an validation is suggested. The individual views are modeled by entity-relationship model. The entities are integrated according to their name and domain information. After that, the relationships are merged by their constraints. We also present a methodology for checking redundant relationships which has an algorithmic description.

• Journal of Internet Computing and Services
• /
• v.8 no.3
• /
• pp.65-74
• /
• 2007

Database integration is a common and growing challenge with the proliferation of database systems, data warehouses, data marts, and other OLAP systems in organizations. Although there are many methods of sharing data between databases, true interoperability of database integration system that improves in the database federation architecture by allowing domain administrators to simply and efficiently capture database semantics. The semantic information is combined using a tool for producing a global view. Building the global view is the bottleneck in integration because there are few tools that support its construction, and these tools often require sophisticated knowledge and experience to operate properly. The technique and tool presented is simple and powerful enough to be used by all database administrators, yet expressive enough to support the majority of integration queries.

• Journal of KIISE:Databases
• /
• v.37 no.6
• /
• pp.333-342
• /
• 2010

Building ontology is the key factor to construct semantic web. However, this is time-consuming process. Hence, there are several approaches which automatically generate the ontologies from relational databases. Current studies on the automatic generation of the ontologies from relational database are focused on generating the ontology by analyzing the database schema and stored data. These studies generate the ontology by analyzing only tables and constraints in the schema and ignore view definitions. However, view definitions are defined by a database designer considering the domain of the database. Hence, by considering view definitions, additional classes and hierarchical relationships can be generated. And these are useful in answering queries and integration of ontologies. In this paper, we formalize the generation of classes and hierarchical relationships by analyzing existing methods, and we propose the method which generates additional classes and hierarchical relationships by analyzing view definitions. Finally, we analyze the generated ontology by applying our method to synthetic data and real-world data. We show that our method generates meaningful classes and hierarchical relationships using view definitions.

• Journal of Information Technology Applications and Management
• /
• v.16 no.4
• /
• pp.245-261
• /
• 2009

Since XML emerged as a standard for data exchange on the web, it has been widely used for applications like e-Commerce, CRM, and BI. However, it is common that most of business data is stored in relational database systems, and it is expected that business data management would still be centered around the relational database systems. As such, the technique of viewing relational data as XML and processing XML queries against it is required. To meet such a need, in the SQL/XML standard, the functions to publish relational data as XML are provided. In this paper, we propose the techniques of providing an XML view of relational data defined by an SQL/XML statement in DTD(Document Type Definition), and of processing XPath queries against the XML view by translating them into SQL/XML statements, and describe the validation of such techniques through implementation and tests.

• The KIPS Transactions:PartD
• /
• v.10D no.2
• /
• pp.221-232
• /
• 2003

This paper addresses the query processing component of a wrapper system for a relational database model based on the XML view in integrating databases. The schema of a relational database is represented as XML Schema that is proposed by W3C. Users submit a query using the XML query language XQuery over the XML Schema. The wrapper system to be developed supports an user-defined XML view. XQuery is also used as the view definition language. In this environment, this paper suggests a new XML query processing model. We propose the composition algorithm of an XML view with an user query, the translation algorithm of XQuery into SQL, and the XML template construction algorithm for generating XML documents.

• The KIPS Transactions:PartD
• /
• v.8D no.4
• /
• pp.377-386
• /
• 2001

In spatial database system, spatial view is supported for efficient access method to spatial database and is managed by materialization and non-materialization technique. In non-materialization technique, repeated execution on the same query makes problems such as the bottle-neck effect of server-side and overloads on a network. In materialization technique, view maintenance technique is very difficult and maintenance cost is too high when the base table has been changed. In this paper, the SVMT (Spatial View Materialization Technique) is proposed by using R-tree re-construction. The SVMT is a technique which constructs a spatial index according to the distribution ratio of objects in spatial view. This ratio is computed by using a SVHR (Spatial View Height in R-tree) and SVOC (Spatial View Object Count). If the ratio is higher than the average, a spatial view is materialized and the R-tree index is re-used. In this case, the root node of this index is exchanged a node which has a MBR (Minimum Boundary Rectangle) value that can contains the whole region of spatial view at a minimum size. Otherwise, a spatial view is materialized and the R-tree is re-constructed. In this technique, the information of spatial view is managed by using a SVIT (Spatial View Information Table) and is stored on the record of this table. The proposed technique increases the speed of response time through fast query processing on a materialized view and eliminates additional costs occurred from repeatable query modification on the same query. With these advantages, it can greatly minimize the network overloads and the bottle-neck effect on the server.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2001.06a
• /
• pp.49-52
• /
• 2001

In this paper, the design and implementation of the Geographic Information Retrieval System for the ArcView is described. The environments for the system configurations include a PC server under Linux Operating System, Apache Web-server, and Oracle as database engine. In addition, JSP(Java Server page) and Servlet is used to view database and Map-Image.

• Korean Management Science Review
• /
• v.13 no.2
• /
• pp.127-146
• /
• 1996

Integrating database views is an important step in the conceptual database design process. This paper develops a view integration support system by using a semantic object model. In order to determine the order of the integration, affinities among views and objects are analyzed by employing the vector space theory. Semantic conflicts such as naming and structural conflicts are then resolved. The resolution results are stored in a view repository. Objects and views are integrated and stored in this view repository until all views are considered. A prototype for the system is built and can be used in a client/server environment.

• Proceedings of the Korea Contents Association Conference
• /
• 2003.05a
• /
• pp.356-360
• /
• 2003

There have been many considerations to develop new content services that integrate a variety of contents databases being already constructed and then produce new content services which are more valuable than existing services in many applications such as Internet portal, EC, and CRM. By doing the above thing, the burden of searching databases to access interesting databases and service applications can be reduced and the database availability of users is also enhanced through a single view integrating multiple contents database. This paper presents implementation details of the query processing system that is a core component of the database integration system, which can construct a virtual database that integrates databases being managed by multiple heterogeneous database systems using XML data model and support a quay facility on the integrated database.

• ETRI Journal
• /
• v.39 no.1
• /
• pp.97-107
• /
• 2017

A fast and accurate building-level visual place recognition method built on an image-retrieval scheme using street-view images is proposed. Reference images generated from street-view images usually depict multiple buildings and confusing regions, such as roads, sky, and vehicles, which degrades retrieval accuracy and causes matching ambiguity. The proposed practical database refinement method uses informative reference image and keypoint selection. For database refinement, the method uses a spatial layout of the buildings in the reference image, specifically a building-identification mask image, which is obtained from a prebuilt three-dimensional model of the site. A global-positioning-system-aware retrieval structure is incorporated in it. To evaluate the method, we constructed a dataset over an area of $0.26km^2$. It was comprised of 38,700 reference images and corresponding building-identification mask images. The proposed method removed 25% of the database images using informative reference image selection. It achieved 85.6% recall of the top five candidates in 1.25 s of full processing. The method thus achieved high accuracy at a low computational complexity.