• Communications for Statistical Applications and Methods
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• v.22 no.4
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• pp.349-359
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• 2015

We study a semiparametric Bayesian approach to small area estimation under a nested error linear regression model with area level covariate subject to measurement error. Consideration is given to radial basis functions for the regression spline and knots on a grid of equally spaced sample quantiles of covariate with measurement errors in the nested error linear regression model setup. We conduct a hierarchical Bayesian structural measurement error model for small areas and prove the propriety of the joint posterior based on a given hierarchical Bayesian framework since some priors are defined non-informative improper priors that uses Markov Chain Monte Carlo methods to fit it. Our methodology is illustrated using numerical examples to compare possible models based on model adequacy criteria; in addition, analysis is conducted based on real data.

• Land and Housing Review
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• v.10 no.1
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• pp.1-7
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• 2019

This article assumes that the first newtown has declined in Korea. Urban regeneration projects should be implemented for regeneration for CBD in Newtown as well as small local cities. The purpose of this article is to analyze the character of the subway area and to suggest the key issues for regeneartion in the subway area. Especially focussing on the local important commercial function in 5 subway areas. As a result of analyzing 5 subway areas according to basic statistical data, field interviews, and legal decline diagnostic index, all five commercial districts showed decline. In particular, the decline of Baekseok Station area appears to be serious, and there is a key factor that attracts the decline of the commercial area such as the long - term building or the closure rate of each commercial area. In addition, the vacancy rate is increasing due to large distribution facilities in new cities, the entry of new floating facilities on the outskirts, and unsold new stores, and the recession is accelerating. In this way, the signs of decline in the core of the new city are enriched, but the current Urban Regeneration Act is a legal system with a policy goal of regeneration of small and medium cities in the provinces as a system to promote the function of core bases rather than the overall redevelopment of new cities. Therefore, preemptive response is needed for the regeneration in those areas.

• Communications for Statistical Applications and Methods
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• v.29 no.5
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• pp.547-559
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• 2022

For a chi-squared test, which is a statistical method used to test the independence of a contingency table of two factors, the expected frequency of each cell must be greater than 5. The percentage of cells with an expected frequency below 5 must be less than 20% of all cells. However, there are many cases in which the regional expected frequency is below 5 in general small area studies. Even in large-scale surveys, it is difficult to forecast the expected frequency to be greater than 5 when there is small area estimation with subgroup analysis. Another statistical method to test independence is to use the Bayes factor, but since there is a high ratio of data dependency due to the nature of the Bayesian approach, the low expected frequency tends to decrease the precision of the test results. To overcome these limitations, we will borrow information from areas with similar characteristics and pool the data statistically to propose a pooled Bayes test of independence in target areas. Jo et al. (2021) suggested hierarchical Bayesian pooling models for small area estimation of categorical data, and we will introduce the pooled Bayes factors calculated by expanding their restricted pooling model. We applied the pooled Bayes factors using bone mineral density and body mass index data from the Third National Health and Nutrition Examination Survey conducted in the United States and compared them with chi-squared tests often used in tests of independence.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5B
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• pp.459-466
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• 2011

In this study, the resources investigations of small hydropower generation were carried out for the five proposed sites in northern Gyeong-buk area. They consisted of the discharge measurements, rating-curve, flow duration curves, electricity generation, and economic analysis, respectively. The basic data were suggested to select the optimal small hydropower sites in northern Gyeong-buk area. The sites for Yecheon Gun and Munsu Myeon as a result are the best proposed ones using economic analysis. We considered, however, that the finacial benefit for small hydropower development may be small under 500 kW facility. The optimal proposed site over 500 kW facility was suggested as Yeongyang Gun in this study.

• Communications for Statistical Applications and Methods
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• v.18 no.4
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• pp.549-557
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• 2011

In this paper, we apply cluster analysis to "Okayama parking data" that is one of the spatial point patterns data that includes locations and the fare structure of car parking space in Okayama central area. This study classifies the characteristics of small areas through Okayama parking data as well as visualizes the results of the cluster analysis. We develop web applications that connect the results of a cluster analysis and overlay objects including points of balloons and rectangles of small areas over a map of Okayama central area.

• Steel and Composite Structures
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• v.46 no.3
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• pp.403-416
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• 2023

This paper summarised and re-examined the theoretical basis of the commonly used design rule developed by Cochrane in the 1920s to consider staggered bolt holes in tension members, i.e., the s²/4g rule. The rule was derived assuming that the term two times the bolt hole diameter (2d₀) in Cochrane's original equation could be neglected, and assuming a value of 0.5 for the fractional deduction of a staggered hole in assessing the net section area. Although the s²/4g rule generally provides good predictions of the staggered net section area, the above-mentioned assumptions used in developing the rule are doubtful, in particular for a connection with a small gauge-to-bolt-hole diameter (g/d₀) ratio. It was found that the omission of 2d₀ in Cochrane's original equation appreciably overestimates the net section area of a staggered bolted connection with a small g/d₀ ratio. However, the assumed value of 0.5 for the fractional deduction of a staggered hole underestimates the staggered net section area for small g/d₀ ratios. To improve the applicability of the above two assumptions, a modified design equation, which covers a full range of g/d₀ ratio, was proposed to accurately predict the staggered net section area and was validated by the existing test data from the literature and numerical data derived from this study. Finally, a reliability analysis of the test and numerical data was conducted, and the results showed that the reliability of the modified design equation for evaluating the net section resistance of staggered bolted connections can be achieved with the partial factor of 1.25.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.5
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• pp.479-485
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• 2011

A number of case studies that find distribution of longevity population and influencing factors through the spatial data fusion using GIS techniques are growing. The majority cases of these studies are adopt census administrative boundary data for the spatial analysis. However, these methods cannot fully explain the phenomenon of longevity because there are a variety of spatial characteristics within the census administrative boundaries. Therefore, studies of spatial unit are required that realistically reflect the phenomenon of human longevity. The dasymetric mapping method enables to product of spatial unit more realistic than census administrative boundary map and statistic estimates of small area utilizing diversity spatial information. In this study, elderly population of small area has been estimated within statistically significant level that applied the vector based dasymetric mapping method. Also, the cluster analysis confirmed that the variation of local spatial relationship within census administrative boundary. The result of this study implied that the need for local-level studies of the human longevity and the validity of the dashmetric mapping techniques.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.755-762
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• 2015

One of the main objectives of the U.S. Census Bureau is the proper estimation of median household income for small areas. These estimates have an important role in the formulation of various governmental decisions and policies. Since direct survey estimates are available annually for each state or county, it is desirable to exploit the longitudinal trend in income observations in the estimation procedure. In this study, we consider Fay-Herriot type small area models which include time-specific random effect to accommodate any unspecified time varying income pattern. Analysis is carried out in a hierarchical Bayesian framework using Markov chain Monte Carlo methodology. We have evaluated our estimates by comparing those with the corresponding census estimates of 1999 using some commonly used comparison measures. It turns out that among three types of time-specific random effects the small area model with a time series random walk component provides estimates which are superior to both direct estimates and the Census Bureau estimates.

• Journal of Korean Academy of Nursing
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• v.21 no.3
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• pp.365-382
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• 1991

This study was designed to measure the physical, mental-emotional and social health status of elderlies according to rural areas, medium - small cities, and large city environment. Data collection was done from July 18 to August 17 1990. The subjects were a convenience sample after their place of residence was stratified into large, medium- small cities and rural areas. Those who attended elderly centers in Seodaemun, Mapo, and Kangnam districts in Seoul were considered to be residents of a large city and interviewed by trained research assistants and student nurses. Elderlies living in Chungju, Jinju, Chuncheon, and Jeonju cities were coded as residents of medium-small cities and were interviewed by professors of nursing colleges. Rural residents were interviewed by the community health practioners working in community health clinics in North and South Kyongsang, North and South Jeolla, and Kyonggi provinces. The tool used in this study was the health assessment tool developed by Choi, Young Hee in 1990. This tool was organized into 20 physical health status, 17 mental - emotional health status, and 37 social health ststus items. Physical health status items consisted of six factors - personal hygiene activity ability, external activity utilizing traffic, mass media, and spare time ability, sexual ability, digestive system related ability, sexual ability, sensory ability, and elimination ability. Mental - emotional health status items consisted of two factors - mental health factor and emotional health factor. Social health status items consisted of seven factors -grandparental role ability, parental role ability, spoused role ability, friendship role ability, kinship role ability, group member role ability, and religious believer role ability. Data Analysis included frequencies, percentage, mean, standard deviation, ANOVA, and chi - square test. The results of the analysis are as follows : 1. The mean physical health status score for large city residents was 4.1132, for rural residents 4.0787, and for medium and small city residents 3.9565. There were significant differences according to residential area for personal hygiene activity ability, external activity ability, sexual ability, and digestive system related ability items 2. The mean mental -emotional health status score for rural residents was 3.8291, for medium and small city residents 3.7967, and for large city residents 3.7807. There was a significant difference according to residential area in the mental health ability item. 3. The mean social health status score for medium and small city residents was 3.0000, for rural residents 2.9362, and for large city residents 2.8960. There were significant differences according to residential area for kinship role ability and religious believer role ability items. The following conclusion was derived from the above results 1. The physical health status of elderlies residing in medium - small cities and in rural areas was lower than that of those residing in Seoul, a large urban area. Therefore, more medical facilities are needed in rural area so as to monitor their health, prevent disease, and promote their health. 2. The mental -emotional ststus and social health status of elderlies residing in the large city were lower than that of those residing in medium - small cities and rural areas. This may reflect weakening of the strong traditional family bond that may happen with urbanization. Continued support for elderly parents is essential and education should emphasize the traditional cultural norm and value of filial piety. 3. Facilities and programs for elderly are needed so that they may spend their time more valuably in their urban environment.

• Journal of the Korean Institute of Rural Architecture
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• v.21 no.1
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• pp.9-16
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• 2019

The decrease in population of school age is one of major influencing factor of transformative educational environment. After the nineteen eighties, the population of South Korea has increased step by step, but the population of school age has been decreasing rapidly by low birth rate. As a result, closed school by merger and abolition of small school occurred all over the country. The closed school needed effective function as center of local community. Consequently the purpose of this study is to provide basic data for effective policy making of closed school by comparative analysis of educational environment such as number of students, schools, students per class, status of usage of closed school of the east area and the west area divided by The Tae Baek Mountains in the Gangwon-do, which has the least students in the nationwide. The results of this study are summarized as follows: 1) Gangwon-do has high decreasing rate of population, schools and students compared with other provinces. However it has significantly low number of students per class. 2) The number of students, schools of the west area in Gangwon-do outnumbers that of the east area. However the number of students per class of the east area in Gangwon-do lesser than that of the west area.