• Journal of the Korean Geographical Society
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• v.43 no.2
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• pp.253-262
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• 2008

The main objective of this paper is to formulate a generalized procedure to extract the first four moments of univariate spatial association measures for statistical testing under the normality assumption and to evaluate the viability of hypothesis testing based on the normal approximation for each of the spatial association measures. The main results are as follows. First, predicated on the previous works, a generalized procedure under the normality assumption was derived for both global and local measures. When necessary matrices are appropriately defined for each of the measures, the generalized procedure effectively yields not only expectation and variance but skewness and kurtosis. Second, the normal approximation based on the first two moments for the global measures fumed out to be acceptable, while the notion did not appear to hold to the same extent for their local counterparts mainly due to the large magnitude of skewness and kurtosis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.391-397
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• 2008

This paper analyzes the spatial patterns of population distribution in Seoul Metropolitan Area in terms of spatial association using spatial statistics and spatial exploratory technique. Our empirical analysis based on global index shows that, in Seoul Metropolitan Area, the population had been distributed with strong positive spatial association over the period of 1980-2005. It implies that the population of each region is affected by the population distribution of adjacent regions. In addition, the analysis using local index was conducted for detecting the local patterns of spatial association, and the result shows that the clusters of population had been moved in the direction of West(Incheon and Bucheon) and South(Anyang and Seongnam) of Seoul where a large scale of lands or towns were developed over the period. These results will be the preliminary data for establishing management and development plans of Seoul Metropolitan Area.

• Patent21
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• s.72
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• pp.20-27
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• 2007

• Journal of KIISE:Databases
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• v.31 no.2
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• pp.163-173
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• 2004

Recently, location-based services are becoming very Popular in mobile environments. In this paper, we propose a new association based prefetch algorithm (called by STAP) that efficiently supports information service based on the large quantity of spatial database in mobile environments. We apply the spatial-temporal relations that are meaningful for location-based queries in mobile environments. Moreover, STAP considers user's mobility and the weight of spatial data. The relation of services is a new aspect not considered in previous cache politics. So STAP is the first prefetch algorithm considering the spatial-temporal relations and thus the cache policy begins to gain a new dimension. We evaluate the performance of STAP and prove the efficiency of STAP.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.4
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• pp.564-579
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• 2008

It is often challenging to evaluate local spatial association among onedimensional vectors generally representing paired-location events where two points are physically or functionally connected. This is largely because of complex process of such geographic phenomena itself and partially representational complexity. This paper addresses an alternative way to identify spatially autocorrelated paired-location events (or vectors) at a local scale. In doing so, we propose a statistical algorithm combining univariate point pattern analysis for evaluating local clustering of origin-points and similarity measure of corresponding vectors. For practical use of the suggested method, we present an empirical application using transactions data in a local housing market, particularly recorded from 2004 to 2006 in Franklin County, Ohio in the United States. As a result, several locally characterized similar transactions are identified among a set of vectors showing various local moves associated with communities defined.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.1
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• pp.29-37
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• 2011

The purpose of this research is to measure Quality of Life indices using Factor Analysis and Principle Component Analysis and to analyze the spatial patterns of Quality of life distribution in the Seoul Metropolitan Area in terms of spatial association using spatial statistics and spatial exploratory technique. In order to check the degree of clustering, this study used spatial autocorrelation indices, global Moran's I index. In addition, local scale analysis was conducted using Moran Scatterplot and Local Moran's I to identify the spatial association pattern and the high Quality of life. The analysis based on global statics showed that, in the Seoul Metropolitan Area, QoL Indices had been distributed with positive spatial association. According to the local spatial statistics, the general tendency of clustering H-H clusters which were mainly concentrated on the Seoul, L-H clusters were concentrated on the Kyunggi-Do and L-L Clusters showed the regional extent of lagging behind. However, in case of H-H, L-H Clusters they had been spread out in the Newtown as population increase.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10a
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• pp.358-360
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• 1999

최근 웹의 활성화로 인하여 인터넷이 대중화되면서 지리 정보 시스템 분야에서도 웹 기반의 공간 데이터의 검색 및 관리의 필요성이 대두되었다. 또한, 지리 정보 시스템에서 다루는 공간 데이터는 가변적이고 대용량이기 때문에 이러한 데이터를 효율적으로 처리하기 위해서는 공간 OODBMS의 사용이 적합하다. 이러한 웹 기반 공간 OODBMS를 사용하는 실제 응용프로그램에서 다중 사용자 환경에서의 협동 작업이 효율적으로 수행되기 위해서는 개별적인 객체 중심의 버전 관리에 그치지 않고 일정 영역내의 연관된 버전화된 객체들의 집합인 복합 객체를 효율적으로 관리하는 것이 절실히 필요하다. 이에 본 논문에서는 다중 사용자 환경에서 연관된 버전화된 집합인 복합 객체를 효율적으로 관리하는 웹기반 공간 OODBMS를 위한 형상 관리자를 설계 및 구현한다. 이를 위해 형상 관리 기능을 지원하는 기존의 시스템인 Open OODB와 RCS, 그리고 SCM에서의 형상 관리 모델에 대해서 알아보고, 형상 관리자의 관리 모델과 자료 구조를 설명한 후 형상 관리자 설계시의 고려사항에 대해서 언급한다. 마지막으로, 형상 관리자의 구성 모듈과 형상 관리가 API에 대하여 기술한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.392-394
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• 2003

연관 규칙 마이닝은 일반적으로 않은 빈발항목집합과 연관 규칙을 생성하며, 생성된 연관 규칙은 상호 포함관계에 있거나 중복되는 경우가 많다. 이는 효과적인 마이닝 뿐 아니라 마이닝의 활용 효용성을 떨어뜨린다. 이를 해결하기 위하여 연관 규칙 마이닝과 동일한 성능을 가지며 생성되는 규칙의 수를 줄일 수 있는 빈발 폐쇄 항목집합 마이닝이 제안되었다. 본 연구에서는 연관규칙 마이닝 방법 중 가장 우수한 성능을 가지는 ARCS 알고리즘을 개선한 빈발 폐쇄 항목집단 마이닝을 제안한다.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2006.05a
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• pp.37-42
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• 2006

GIS분야에 대한 다양한 연구가 진행됨에 따라 그 활용에 대한 관심도 확대되고 있다. Open GIS Consortium에서는 GML(Geography Markup Language)을 개발하여 이를 GIS 응용분야에 활용하고자 하는 연구가 활발히 진행되고 있다. GML데이터에서 의미 있는 정보를 추출하기 위해서는 데이터 마이닝 기법 활용이 필수적이다 최근에 데이터마이닝 기법 중 연관규칙을 이용한 탐색 방법이 제안되었다. 그러나 이 방법은 전체 데이터를 대상으로 의미 있는 정보를 탐색 하므로, 데이터 내에 포함되어 있는 부분 속성인 지리 공간적 연관성을 탐색하는데 한계를 가지고 있다. 따라서 녈 연구에서는 GML데이터에서 부분적 속성을 고려한 지역적 연관규칙 탐색 기법을 제안한다.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.113-126
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• 2017

This study aimed to quantitatively analyze the trends in environmental research that utilize environmental geospatial information through text mining, one of the big data analysis technologies. The analysis was conducted on a total of 869 papers published in the Republic of Korea, which were collected from the National Digital Science Library (NDSL). On the basis of the classification scheme, the keywords extracted from the papers were recategorized into 10 environmental fields including "general environment", "climate", "air quality", and 20 environmental geospatial information fields including "satellite image", "numerical map", and "disaster". With the recategorized keywords, their frequency levels and time series changes in the collected papers were analyzed, as well as the association rules between keywords. First, the results of frequency analysis showed that "general environment"(40.85%) and "satellite image"(24.87%) had the highest frequency levels among environmental fields and environmental geospatial information fields, respectively. Second, the results of the time series analysis on environmental fields showed that the share of "climate" between 1996 and 2000 was high, but since 2001, that of "general environment" has increased. In terms of environmental geospatial information fields, the demand for "satellite image" was highest throughout the period analyzed, and its utilization share has also gradually increased. Third, a total of 80 correlation rules were generated for environmental fields and environmental geospatial information fields. Among environmental fields, "general environment" generated the highest number of correlation rules (17) with environmental geospatial information fields such as "satellite image" and "digital map".