• 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.

• Journal of Korean Association for Spatial Structures
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• v.8 no.2
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• pp.14-21
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• 2008

• Korean Journal of Social Welfare Studies
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• no.37
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• pp.35-62
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• 2008

This study starts form the inequity of the spatial accessibility in social services. This study has purpose to descript and analyze the spatial accessibility of social service agencies. While analysing the spatial accessibility, this paper uses comparative method of distance and space-time measures. The results of research are as follows; It needs (1) to enhance the spatial accessibility of the aged and the disabled. (2) to facilitate the spatial accessibility of marginal area or community like rural community. (3) to recognize utilities of distance and space-time measures in the spatial accessibility.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.616-631
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• 2007

Residential differentiation is an academic theme which has been given enormous attention in urban studies. This is due to the fact that residential segregation can be seen as one of the best indicators for socio-spatial dialectics occurring on urban space. Measuring how one population group is differentiated from the other group in terms of residential space has been a focal point in the residential segregation studies. The index of dissimilarity has been the most extensively used one. Despite its popularity, however, it has been accused of inability to capture the degree of spatial clustering that unevenly distributed population groups usually display. Further, the spatial indices of segregation which have been introduced to edify the problems of the index of dissimilarity also have some drawbacks: significance testing methods have never been provided; recent advances in spatial statistics have not been extensively exploited. Thus, the main purpose of the research is to devise a spatial separation measure which is expected to gauge not only how unevenly two population groups are distributed over urban space, but also how much the uneven distributions are spatially clustered (spatial dependence). The main results are as follows. First, a new measure is developed by integrating spatial association measures and spatial chi-square statistics. A significance testing method based on the generalized randomization test is also provided. Second, a case study of residential differentiation among groups by educational attainment in major Korean metropolitan cities clearly shows the applicability of the analytical framework presented in the paper.

• Journal of the Korean association of regional geographers
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• v.12 no.4
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• pp.508-521
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• 2006

The results of environmental equity analysis vary dramatically depending on different methods used. The information and data available to the researcher are also often uncertain and imprecise in empirical studies. A sensitivity analysis approach was used too handle uncertainties and methodological inconsistencies in environmental equity analysis. This paper explores the sensitivity of environmental equity analysis to two spatial measures such as proximity and scale. Two experiments were implemented to evaluate the effects of two spatial measures on the environmental equity analysis using a combination of control and experimental factors. Fulton County, Georgia was selected as a case study area for these experiments. Two major data sets including demographic characteristics and toxic release inventory (TRI) database for the study area in 1990 were integrated into a GIS environment. Two statistical analyses such as independent samples t-test and coefficient of variation were performed to determine the environmental equity in the study area and to compare the relative variability in the socioeconomic characteristics of populations over different spatial measures. The findings from two experiments indicate that the outcomes of environmental equity analysis are slightly sensitive to the buffer distance used to determine the impact zones of TRI facilities, but not to the geographic scale used in the analysis. The findings also suggest that the consequences of these choices can alter spatially and statistically the results in environmental equity analysis.

• Journal of Korea Water Resources Association
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• v.43 no.11
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• pp.933-944
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• 2010

This study compares the CEM and SGS methods which are geostatistical stochastic simulation methods for assessing the uncertainty by spatial variability in the estimation of the spatial distribution of probability rainfall. In the stochastic simulations using CEM and SGS, two methods show almost similar results for the reproduction of spatial correlation structure, the statistics (standard deviation, coefficient of variation, interquartile range, and range) of realizations as uncertainty measures, and the uncertainty distribution of basin mean rainfall. However, the CEM is superior to SGS in aspect of simulation efficiency.

• Journal of the Korean housing association
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• v.25 no.5
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• pp.43-50
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• 2014

This study assesses thermal environment of detached housing area by classifying buildings types with codes based on spatial characteristics and forms of the detached housing area and applying heat island alleviation measures, especially focused on FBCs (Form-Based Codes). We analyzed shapes and materials of outdoor space with 3D-CAD, which can affect the surface temperature of the case studies, focusing on heat island alleviation measures, and performed space design by applying relevant climate factors to a simulation. As to the 3D surface temperature and HIP distribution, low-temperature distribution was shown in the case studies when we applied heat island alleviation measures. FBCs (Form- Based Codes) is being developed for the purpose of creating new urban environment. This study is significant because it pays attention to the effects of surface temperatures on accumulation of sensible heat and reviews heat island alleviation measures with outdoor space shapes/materials in order to lower surface temperatures, aiming at improved pleasantness of the detached housing area.

• Journal of the Korean association of regional geographers
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• v.16 no.5
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• pp.610-622
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• 2010

The proportion of overweight and obese individuals in the United States has been continuously increasing up to recently. Many studies related to obesity have concentrated on jurisdictional levels of aggregation, making it very difficult to dearly illustrate at risk regions. In other words, little research has been conducted in relation to spatial patterns considering spatial dependency and heterogeneity by spatial autocorrelation models over space. In response, this research analyzes spatial patterns between overweight/obesity and risk factors, such as high blood pressure and diabetes, over space. Specifically, the Moran''s I and Geary''s C will be conducted for global and local measures. What is more, the Ordinary Least Square (OLS) linear regression and Geographically Weighted Regression methods will be applied to identify spatial dependency and spatial heterogeneity. Data provided by the Behavioral Risk Factor Surveillance System (BRFSS) have Body-Mass Index (BMI) rates, containing 4 rates of under, healthy, overweight, and obesity. In addition, high blood pressure and diabetes rates in the United States will be used as independent variables. Lastly, we are confident that this research will be beneficial for a decision maker to make a prevention plan for obesity.

• Journal of Korean Association for Spatial Structures
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• v.12 no.2
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• pp.55-63
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• 2012

This study is about earthquake-proof reinforcement through structural function evaluation of an school building. The purpose of this study is to comparatively analyze structure reinforcement measures in consideration of safety and usability through structural function evaluation of school buididng, to offer rational measures for earthquake-proof function and to provide help in maintaining safe structures against earthquake. For this purpose, was selected for this study as an existing school building, earthquake-proof function evaluation was conducted, and measures to reinforce earthquake-proof function was offered. As for the research method, the first and the second earthquake-proof function evaluations were conducted which is an existing reinforced concrete school building. Through the abovementioned methods, earthquake-proof function evaluation were conducted, the results were analyzed and the measure to reinforce earthquake-proof function were offered(Steel damper, Carbon plate stiffeners). The offered measure to reinforce earthquake-proof function was applied to the subject structure, and comprehensive results were derived from earthquake-proof function evaluation regarding before and after earthquake-proof function reinforcement.

• Child Studies in Asia-Pacific Contexts
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• v.7 no.1
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• pp.27-38
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• 2017

As the use of digital media is becoming more universal and is being used in early-childhood education, understanding the effects of digital media on development is required. The purpose of this study was to examine whether child performance on a spatial cognition task depends on the type of media used to present the task and if the effect of media type is different depending on child's age and sex. To do this, a spatial cognition task set (consisting of direction, rotation, symmetry, conjugation, and part/whole tasks) was prepared, and these tasks were presented to 60 3-, 4-, and 5-year-old children using paper- and tablet-based measures. Our results showed that the correct answer rate of task performance differed significantly when completing the task on a tablet than when completing the task on paper. Generally, response times when completing the tasks on a tablet was significantly shorter than when completing the tasks on paper. Although there was no interaction between the type of media and age, and partial interaction was found between the type of media and sex. This result implies an influence of digital stimulation on child performance on the spatial cognitive task. This study provides a basic understanding for follow-up studies to examine the consequences of exposure to digital stimulation.