• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8370-8377
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• 2015

In spatial data stream management systems, it is needed appropriate load shedding algorithm because real-time input spatial data streams could exceed the limitation of main memory. However previous researches, lack regard for input ratio and spatial utilization rates of spatial data streams, or the characteristics of data source which generates data streams with spatial information efficiently, can lead to decrease the performance and accuracy of spatial data stream query. Therefore, multi-level load shedding scheme for spatial data stream management systems is proposed to increase the spatial query performance and accuracy. This proposed scheme limits overloads in relation to the input rate and the characteristics of data source first, and then, if needed, query data representing low query participation probability based on spatial utilizations are dropped relatively. Our experiments show that the proposed method could decrease load shedding frequency for previous researches by more than 11% despite query results accuracy and query performance are superior at 0.04% and 3%.

• The KIPS Transactions:PartD
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• v.10D no.4
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• pp.567-576
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• 2003

Spatial data mining, i.e., discovery of interesting characteristics and patterns that may implicitly exists in spatial databases, is a challenging task due to the huge amounts of spatial data. Clustering algorithms are attractive for the task of class identification in spatial databases. Several methods for spatial clustering have been presented in recent years, but have the following several drawbacks increase costs due to computing distance among objects and process only memory-resident data. In this paper, we propose an efficient grid cell based spatial clustering method for spatial data mining. It focuses on resolving disadvantages of existing clustering algorithms. In details, it aims to reduce cost further for good efficiency on large databases. To do this, we devise a spatial clustering algorithm based on grid ceil structures including cell relationships.

• Journal of KIISE:Software and Applications
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• v.26 no.9
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• pp.1061-1072
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• 1999

한 개 이상의 사이트에 공간 데이타가 중복 저장된 분산 공간 DB에서, 동시에 수행될 수 있는 긴 트랜잭션의 변경은 일관성 제어를 위해 다른 사이트에 전파되어야 한다. 이때 같은 영역의 공간 데이타를 서로 다른 사이트에서 동시에 변경할 경우, 변경 상충 문제가 발생하거나 잠금 기법에 의한 오랜 대기 시간이 초래되는 문제가 있다. 또한 공간 객체는 잠금의 대상이 아닌 공간 관련성에 의한 종속성을 가진다.이 논문은 긴 트랜잭션으로 중복된 공간 데이타를 변경할 경우 중복 제어를 위한 변경 전파와 동시성 제어 문제를 다룬다. 중복된 공간 데이타의 변경 병렬성을 향상시키기 위해 영역 잠금 및 SR-bound WRITE 잠금 기법을 제시한다. 한 사이트에서 수정하는 객체들과 다른 사이트에서 수정하는 객체들 사이에 공간 관련성에 의한 종속성이 없을 경우 병렬 수정을 허용하도록 제어하며, 공간 관련성에 의한 종속성이 있을 경우 SR-based 2PC라 불리는, 확장된 2단계 완료 프로토콜로 협동작업을 수행해서 변경 상충을 해결하는 새로운 중복 제어 기법을 설계하고 구현한다.Abstract The update of a long transaction should be propagated to the other sites for consistency control, when spatial database are replicated at multiple sites to achieve availability, reliability, and performance. When the replicated spatial data are updated at the same time, the update of one site would be conflicted with the other or a user would not be able to access the replicated spatial data under the control of locking. Two spatial objects having spatial relationships should be cooperatively updated even if there are no conflicts of locking for them.This paper deals with the issues of concurrency control and update propagation of replicated spatial data. We present the concept of region lock and SR-bound WRITE lock for enhancing the parallelism of updating the replicated spatial data. If there are no spatial relationships between one site's objets and the other's objects, parallel update would be allowed. Concurrent update of two spatial objects having spatial relationships should be propagated and cooperated by using an extended two-phase commit protocol, called spatial relationship-based 2PC.

• Spatial Information Research
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• v.21 no.2
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• pp.85-97
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• 2013

The accumulation of spatial information - people, building, land and businesses- is required to make a rational decision successfully by utilizing the Spatial Decision Support Systems (SDSS). Many foreign countries have utilized the SDSS by defining the minimum unit of spatial area and implementing the spatial database based on it. Even though in Korea, National Basic Districts were created for the purpose of utilizing these districts as a basic area, they have not been utilized as a basic area of managing the spatial database due to the lack of attributes data. Therefore, the goal of this research is to suggest the strategies of building Spatial Decision Support Systems through the accumulation of the spatial data based on National Basic Districts. We propose the strategies in three different fields - legal system, database and application, services. We expect that the role of National Basic Districts w ill be strengthened by executing our strategies as a minimum spatial unit of Korea.

• Journal of architectural history
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• v.21 no.6
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• pp.19-34
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• 2012

This paper focuses on the spatial analysis of traditional houses in Huizhou during the Ming and Qing period in China. It first reviews the spatial characteristics of the houses in Huizhou. Typical configurations, spatial elements and spatial compositions of the houses are briefly examined. It then discusses how those spatial characteristics are applied to the houses. To do so, the review of existing research and literature on the houses was conducted. For a detailed analysis of the houses, a field survey was performed to collect research materials of the houses and to assess the application of the characteristics in the houses. At times, the plans of the houses were redrawn for a further analysis of the spatial compositions of the houses. Attempts have been made to understand the underlying principles of their spatial organization. For example, Jin (2010) examined the spatial organization of unit plans. Boyd (1989), Berliner (2003) and Dan (2005) similarly categorized the organizational typology of its varying designs. Son(1995) further interpreted the spatial relations of the variety of houses in a comprehensive manner. Nevertheless, their analytic methodology falls short of a complete explanation of the spatial expansion and transformation in the houses. Therefore, this paper examines the basic principles behind the spatial expansion and transformation of a variety of traditional houses in Huizhou. In doing so, it strives to make logical sense of design variations in the houses and reveal the theory behind them.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.500-509
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• 2003

A land-speculation is to occur on a space. A purpose of this study interprets land speculation in a viewpoint of spatial, and to carry out effective decision-making about areas that land-speculation can be arise At the time of this, the focus of spatial interpretation Is recognition of a spatial continuity and consideration of a spatial association. In this study, I used fuzzy sets in order to recognize spatial continuity and. therefore a value in 0-1 was granted all area. And in order to consider spatial associations. carried out a local spatial association (Local Moran's I). Also. I introduced the spatial expert support systems (SESS) one of the computer-based decision support systems to dr efficient decision-making about a land-speculation in an object area. After that, as a case study I carried out decision-making about land-speculation's occurrence in the Seoul-Kyeonggi (2/4 quarter in 2001)

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.1
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• pp.121-129
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• 2009

Today, it is difficult to re-use and share spatial information, because of the explosive growth of heterogeneous information and specific characters of spatial information accumulated by diverse local agency. A spatial analysis of subsurface spatial informa-tion, one of the National Spatial Data Infrastructure, needs related spatial information such as, topographical map, geologic map, underground facility map, etc. However, current methods using standard format or spatial datawarehouse cannot consider a se-mantic hetergenity. In this paper, the layered ontology model which consists of generic concept, measuremnt scale, spatial model, and subsurface spatial information has developed. Also, the current ontology building method pertained to human experts is a expensive and time-consuming process. We have developed the MDA-based metamodel(UML Profile) of ontology that can be a easy under-standing and flexiblity of environment change. The semantic quality of devleoped ontology model has evaluated by reasoning engine, Pellet. We expect to improve a semantic sharing, and strengthen capacities for developing GIS experts system using knowledge representation ability of ontology.

• Journal of the Korean Society of Earth Science Education
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• v.5 no.1
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• pp.20-30
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• 2012

The purpose of this study is to find how elementary students who have different spatial ability affects their understandings on the concept of the rotation of the earth. In order to perform this study, four 5th grade students were picked out of 85 students in Seoul. They had the same conceptual achievement on the movement of celestial bodies but had different spatial abilities. The results of this study were as follows : Regardless of their spatial ability, they understand how day and night are performed, and understand the fact that diurnal motions of moon are related to the rotation of the earth. Also, the students who had higher spatial abilities showed better understanding on the concept of the rotation of the earth and understood the reconstructed concepts in stereoscopic space. But the students who had lower spatial abilities did not fully understand the concept of the rotation of the earth and just memorized them as fragmentary concepts. As for the gender differences, the boy students who had higher spatial ability explained the concept clearly and the others who had lower spatial ability had difficulty in understanding the rotation direction of the earth related with the diurnal movement of celestial bodies. In the same manner, the girl students who had higher spatial ability explained the concepts concretely and the others who had lower spatial ability had difficulty in explaining the concepts by operating them stereoscopically. Therefore, developing teaching methods and studying data and so on, for the girl students, they should be trained to operate the stereoscopic space directly, and for the boy students, they should learn to think over objects with multi-viewpoints. And then the spatial ability on the movement of celestial bodies would be expected to be improved.

• Ocean and Polar Research
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• v.29 no.4
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• pp.391-400
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• 2007

To identify the spatial distribution pattern of water quality in Masan Bay, Pearson's correlation as a common statistic method and Moran's I as a spatial autocorrelation statistics were applied to the hydrological data seasonally collected from Masan Bay for two years ($2004{\sim}2005$). Spatial distribution of salinity, DO and silicate among the hydrological parameters clustered strongly while chlorophyll a distribution displayed a weak clustering. When the similarity matrix of Moran's I was compared with correlation matrix of Pearson's r, only the relationships of temperature vs. salinity, temperature vs. silicate and silicate vs. total inorganic nitrogen showed significant correlation and similarity of spatial clustered pattern. Considering Pearson's correlation and the spatial autocorrelation results, water quality distribution patterns of Masan Bay were conceptually simplified into four types. Based on the simplified types, Moran's I and Pearson's r were compared respectively with spatial distribution maps on salinity and silicate with a strong clustered pattern, and with chlorophyll a having no clustered pattern. According to these test results, spatial distribution of the water quality in Masan Bay could be summed up in four patterns. This summation should be developed as spatial index to be linked with pollutant and ecological indicators for coastal health assessment.

• Korean Journal of Remote Sensing
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• v.24 no.2
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• pp.117-124
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• 2008

This paper introduces a novel approach for automated mapping of a map feature that is vinyl green house in high spatial resolution imagery Some map features have their unique spatial patterns. These patterns are normally detected in high spatial resolution remotely sensed data by human recognition system. When spatial patterns can be applied to map feature identification, it will improve image classification accuracy and will be contributed a lot to feature identification. In this study, an automated feature identification approach using spatial aucorrelation is developed, specifically for the vinyl green house that has distinctive spatial pattern in its array. The algorithm aimed to develop the method without any human intervention such as digitizing. The method can investigate the characteristics of repeated spatial pattern of vinyl green house. The repeated spatial pattern comes from the orderly array of vinyl green house. For this, object-based approaches are essential because the pattern is recognized when the shapes that are consists of the groups of pixels are involved. The experimental result shows very effective vinyl house extraction. The targeted three vinyl green houses were exactly identified in the IKONOS image for a part of Jeju area.