• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.2
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• pp.87-96
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• 2004

When watershed spatial database is constructed from DEM, hydrological geographic characteristics of watershed can be easily extracted. And the characteristics can be assigned and managed as the attribute of spatial database. In this study the scheme of constructing framework spatial database which is basic information for managing watershed information is examined. We established framework spatial data and defined the relationship of the data. And framework spatial database of test site was constructed. In this study, HyGIS(Hydrological Geographic Information System) which is developed by domestic technology for making hydrological spatial data and developing water resources system is used. Hydrological geographic characteristics and spatial data is extracted by HyGIS. And the data from HyGIS is used for constructing framework spatial database of test site. Finally, this study suggests the strategy of constructing framework spatial database for developing watershed management system based on river network.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.1
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• pp.43-54
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• 2001

In this paper we study the use of polyinstantiation for spatial data, for the purpose of solving cover in topology channel in multilevel secure spatial database systems. Spatial database system with topological structure has a number of spatial analysis function using spatial data and neighbored one\`s each other. But. it has problems that information flow is occurred by topological relationship in spatial database systems. Geographic Information System(CIS) must be needed mandatory access control because there ,are many information flow through positioning information And topological relationship between spatial objects. Moreover, most GIS applications also graphe user interface(GUI). In addressing these problems, we design the MLS/SRDM(Multi Level Security/Spatial Relational Data Model) and propose polyinstantiation for spatial data for solving information flow that occurred by toplogical relationship of spatial data.

• Journal of Korea Spatial Information System Society
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• v.11 no.1
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• pp.79-86
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• 2009

The tuple of constraint database consists of constraint logical formula and it could process the presentation and query of the constraint database simply. Query operation processing shall include the constraint formula between related tuple such as selection, union, intersection of spatial data through the constraint database. However, this could produce the increasing of duplicated or unnecessary data. Hence, it will drive up the cost as per quality. This paper identified problems regarding query processing result in the constraint database. Also this paper suggested the tuple minimization summary method for result relation and analyzed the effects for efficient query processing. We were able to identify that the effectiveness of the query processing was enhanced by eliminating unnecessary constraint formula of constraint relation using the tuple minimization method.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.766-768
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• 2003

Selectivity estimation for spatial query is curial in Spatial Database Management Systems(SDBMS). Many works have been performed to estimate accurate selectivity. Although they deal with some problems such as false-count, multi-count arising from properties of spatial dataset, they can not get such effects in little memory space.* Therefore, we need to compress spatial dataset into little memory. In this paper, we propose a new technique called MW Histogram which is able to compress summary data and get reasonable results. Our method is based on two techniques:(a)MinSkew partitioning algorithm which deal with skewed spatial datasets. efficiently (b) Wavelet transformation which compression effect is proven. We evaluate our method via real datasets. The experimental result shows that the MW Histogram has the ability of providing estimates with low relative error and retaining the similar estimates even if memory space is small.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1491-1496
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• 2009

Because of the development of advanced construction technology, the inner environments of building become more and more complicated, which may result in many problems. The administer may forget where they put up the certain picture, and search for it all over the building, or they underestimate the number of the visitors, and find the situation is out of control, while the pedestrian may get lost, and after making their efforts, they found they turned back to the origin point again. So it is very necessary to establish an indoor spatial database. On one hand, it is able to assist administrator to manage the property and human flow inside the building, on the other hand it could help the pedestrian find the way easily especially when they are not familiar with the building or there is an emergency. This paper focused on how to create the indoor spatial database including both static database and moving objects database. The static database is built on the basis of 3D building models, and the moving objects database gets information from many kinds of cameras and sensors installed in the building. And at the same time the paper discussed the practical use of indoor spatial database mainly in three aspects including consistency management, building restructure, and pedestrian navigation.

• Journal of Intelligence and Information Systems
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• v.9 no.3
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• pp.99-115
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• 2003

In this paper, we present a knowledge-based object-oriented spatial database system called KOBOS. A knowledge-based approach is introduced to the object-oriented spatial database system for data modeling and approximate query answering. For handling the structure of spatial objects and the approximate spatial operators, we propose three levels of object-oriented data model: (1) a spatial shape model; (2) a spatial object model; (3) an internal description model. We use spatial type abstraction hierarchies(STAHs) to provide the range of the approximate spatial operators. We then propose SOQL, a spatial object-oriented query language. SOQL provides an integrated mechanism for the graphical display of spatial objects and the retrieval of spatial and aspatial objects. To support an efficient hybrid query evaluation, we use the top-down spatial query processing method.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.1
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• pp.89-97
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• 2003

This study is aimed at standardizing the process of spatial database construction and developing a software tool for process management. Knowhow of five GIS firms and provisions of NGI(National Geography Institute) was analyzed. In this study, the process of spatial database construction was standardized. The system from this study has the capability to manage the process of construction database using GIS and to deal with the metadata of unit map, generated from the process, systematically and continuously. The process was also shown by using either Gantt chart or PERT chart after developing an interface for "MS Project". A software "Visual Basic for Application" was used for this study.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.04a
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• pp.285-290
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• 2003

This study is aimed at standardizing the process of spatial database construction and developing a software tool for process management. Knowhow of five GIS firms and provisions of NGI(National Geography Institute) were analyzed. In this study, the process of spatial database construction was standardize. The system from this study has the capability to manage the process of construction database using GIS and to deal with the metadata of unit map, generated from the process, systematically and continuously The process was also shown by using either Gantt chart or PERT chart after developing an interface for "MS Project". A software "Visual Basic for Application" was used for this study.

• Spatial Information Research
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• v.12 no.4 s.31
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• pp.307-319
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• 2004

Managing GML data in traditional database systems is not efficient since It has not only characteristics of spatial data but also features of (semi) structured n documents. XML enabled database systems can manage U data efficiently, however they cannot handle spatial data. Spatial database systems are good at spatial data handling but those are inefficient for XML data. This paper proposes a storage method of GML data for spatial database systems in order to solve the problems. The proposed method generates spatial database schemas from GML application schemas and store GML data into SDBMS through the generated schemas. A prototype of the storage method has been implemented on the Postgre SQ/SPE system to show the proposed method is appropriate for storing GML data. As a result, the implemented system was able to store various GML data which had diverse XML structures and different size. Stored data size was smaller than GML files. Furthermore, spatial, non-spatial, and mixed content queries could be performed over the stored GML data as quickly.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.1
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• pp.81-95
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• 2009

The CDB(Constraint Database) model is a new paradigm for massive spatial data processing such as GIS(Geographic Information System). This paper will identify the limitation of the schema structure and query processing through prior spatial database research and suggest more efficient processing mechanism of constraint data model. We presented constraint model concept, presentation method, and the examples of query processing. Especially, we represented TIN (Triangulated Irregular Network) as a constraint data model which displays the height on a plane data and compared it with prior spatial data model. Finally, we identified that we were able to formalize spatial data in a simple and refined way through constraint data modeling.