• Title/Summary/Keyword: Areal Analysis

Search Result 230, Processing Time 0.021 seconds

An Approach on the Spatial Boundary of Rural Development Project by Areal Classification Technique - With Spatial Reference to Searching of Areal Homogeneities in Two Hierachial Administrative Units, Ri, Eup/Myun - (유형화기법에 의한 농촌지역개발범역 설정방향모색 - 리/읍.면 단위지역의 지역특성 규명을 중심으로 -)

  • 전영길;류수형
    • Journal of Korean Society of Rural Planning
    • /
    • v.4 no.2
    • /
    • pp.128-137
    • /
    • 1998
  • The objective of this study is to approach on the spatial boundary of rural development protect by areal classification technique with spatial reference to searching of areal homogeneities in two hierachial administrative units, Ri Eup/Myun. In this study, a criterion for judging areal homogeneities is the degree of agriculture and urbanizing. Variables selected by these two criteria are analysed with the method of fator analysis. The results of areal analysis are as follows: first, generally, the importance of agricultural factors in areal analysis is getting less. Second, areal classification by Myun, Ri in Ansong City is revealed variously because of urban factors. Urban factors make areal heterogeneities become greater, Therefore urban factors are important when analyzing areal characteristics. Third, lately, in areas near by Chung- cheong Do and areas with bad road's condition, areal heterogeneities have been also getting greater. The results of analysis about areal characteristics of Myun and Ri are different from each other. In addition, urban factors are more influential on the areal characteristics than agricultural factors. Therefore, the establishment of rural development project for inindle spatial boundary between Myun unit and Ri unit is needed.

  • PDF

Maximum Areal Rainfall of Korea in the 20th Century (20세기 우리나라 관측최대강수량의 특성)

  • Kim, Nam-Won;Won, Yoo-Seung
    • Journal of Korea Water Resources Association
    • /
    • v.37 no.5
    • /
    • pp.425-435
    • /
    • 2004
  • Mainly, observed maximum rainfall has been evaluated by point rainfall, but actually it should be considered by means of average areal rainfall. Average areal rainfall is an estimated value computed through DAD(rainfall Depth-Area-Duration) analysis. By using this value, an average and maximum areal rainfall according to area-duration relationship could be computed. In this study, we assume that the whole Korea region is hydrologically homogeneous, and then analyze using the storm-centered DAD(moving-area DAD) method for the past century data. From this analysis, we evaluate the yearly variation of observed maximum areal rainfall through area-duration relationship. And we also construct an IDF(rainfall Intensity-Duration-Frequency) curve by using the annual time series data which is composed of maximum areal rainfall. The characteristics of IDF and observed maximum areal rainfall is also evaluated.

Effects of Areal Interpolation Methods on Environmental Equity Analysis (면내삽법이 환경적 형평성 분석에 미치는 영향)

  • Jun, Byong-Woon
    • Journal of the Korean association of regional geographers
    • /
    • v.14 no.6
    • /
    • pp.736-751
    • /
    • 2008
  • Although a growing number of studies have commonly used a simple areal weighting interpolation method to quantify demographic characteristics of impacted areas in environmental equity analysis, the results obtained are inevitably imprecise because of the method's unrealistic assumption that population is evenly distributed within a census enumeration unit. Two alternative areal interpolation methods such as intelligent areal weighting and regression methods can account for the distributional biases in the estimation of impacted populations by making use of additional information about the geographic distribution of population. This research explores five areal interpolation methods for estimating the population characteristics of impacted areas in environmental equity analysis and evaluates the sensitivity of the outcomes of environmental equity analysis to areal interpolation methods. This study used GIS techniques to allow areal interpolation to be informed by the distribution of land cover types, as inferred from a satellite image. in both the source and target units. Independent samples t-test statistics were measured to verify the environmental equity hypothesis while coefficients of variation were calculated to compare the relative variability and consistency in the socioeconomic characteristics of populations at risk over different areal interpolation methods. Results show that the outcomes of environmental equity analysis in the study area are not sensitive to the areal interpolation methods used in estimating affected populations, but the population estimates within the impacted areas are largely variable as different areal interpolation methods are used. This implies that the use of different areal interpolation methods may to some degree alter the statistical results of environmental equity analysis.

  • PDF

A Comparative Analysis of the Accuracy of Areal Precipitation According to the Rainfall Analysis Method of Mountainous Streams

  • Kang, Bo-Seong;Yang, Sung-Kee;Kang, Myung-Soo
    • Journal of Environmental Science International
    • /
    • v.28 no.10
    • /
    • pp.841-849
    • /
    • 2019
  • The purpose of this study was to evaluate the method of estimating the areal precipitation reflecting the altitude of the mountainous terrain on Jeju Island by comparing and analyzing the areal precipitation using the Thiessen polygon method and the isohyetal method in mountainous streams. In terms of constructing the Thiessen polygon network, rainfall errors occurred in 94.5% and 45.8% of the Thiessen area ratio of the Jeju and Ara stations, respectively. This resulted in large areal precipitation and errors using the isohyetal method at altitudes below 600 m in the target watershed. In contrast, there were small errors in the highlands. Rainfall errors occurred in 18.91% of the Thiessen area ratio of Eorimok, 2.41% of Witseoreum, and 2.84% of Azalea Field because of the altitudinal influence of stations located in the highlands at altitudes above 600 m. Based on the areal precipitation estimation using the Thiessen polygon method, it was considered to be partially applicable to streams on Jeju Island depending on the altitude. However, the method is not suitable for mountainous streams such as the streams on Jeju Island because errors occur with altitude. Therefore, the isohyetal method is considered to be more suitable as it considers the locations of the rainfall stations and the orographic effect and because there are no errors with altitude.

The Effect of Geographic Units of Analysis on Measuring Geographic Variation in Medical Services Utilization

  • Kim, Agnus M.;Park, Jong Heon;Kang, Sungchan;Hwang, Kyosang;Lee, Taesik;Kim, Yoon
    • Journal of Preventive Medicine and Public Health
    • /
    • v.49 no.4
    • /
    • pp.230-239
    • /
    • 2016
  • Objectives: We aimed to evaluate the effect of geographic units of analysis on measuring geographic variation in medical services utilization. For this purpose, we compared geographic variations in the rates of eight major procedures in administrative units (districts) and new areal units organized based on the actual health care use of the population in Korea. Methods: To compare geographic variation in geographic units of analysis, we calculated the age-sex standardized rates of eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee-replacement surgery, caesarean section, hysterectomy, computed tomography scan, and magnetic resonance imaging scan) from the National Health Insurance database in Korea for the 2013 period. Using the coefficient of variation, the extremal quotient, and the systematic component of variation, we measured geographic variation for these eight procedures in districts and new areal units. Results: Compared with districts, new areal units showed a reduction in geographic variation. Extremal quotients and inter-decile ratios for the eight procedures were lower in new areal units. While the coefficient of variation was lower for most procedures in new areal units, the pattern of change of the systematic component of variation between districts and new areal units differed among procedures. Conclusions: Geographic variation in medical service utilization could vary according to the geographic unit of analysis. To determine how geographic characteristics such as population size and number of geographic units affect geographic variation, further studies are needed.

A Study on the Architectural Planning of the Areal Composition of Provincial Medical Center (지방공사 의료원의 면적구성에 관한 건축계획적 연구)

  • Kim, Khil-Chae
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.14 no.2
    • /
    • pp.35-42
    • /
    • 2008
  • Over the last 10 years several Provincial Medical Center has been carried out rapidly in the welfare facilities in Korea. Provincial Medical Center is for public and economic. So This study is an analysis of the areal composition between the Provincial Medical Center and General Hospital in Korea. The changes of Provincial Medical Center are caused by role in the environments. The Factor of economic is more important than for public in this situation. This paper analyzes architectural drawings for 4 Korean medical center which constructed in recent 10 years in aspects of the spacial composition, presents areal composition and pattern of spacial allocation for researching hospitals. According to the areal composition of Provincial Medical Center is important in healthcare facility environment.

  • PDF

한국 센서스데이터의 MAUP

  • 강계화
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
    • /
    • 2003.11a
    • /
    • pp.3-8
    • /
    • 2003
  • Census data are usually provided at an aggregated level. However, the aggregated data are essentially arbitrary geographical areas. The areal units used to report census data have no natural or meaningful geographical identity. Unfortunately, this means that analyses of these area aggregations may be conditional upon the set of zones, which are presented. This effect is known as the modifiable areal unit problem (MAUP) and has two related aspects. First, scale effect is the variation in numerical results that occurs due to the number of zones used in an analysis. Second, results may also differ between different ways of aggregating exactly the same data to the same scale; this may be called the aggregation effect (Openshaw, 1984). This study aims to provide a practical tool for the study of MAUP. I have created a set of 91 areal units based on 280 basic units in Nonhyun-2 dong to solve zoning problem and scale problem. We can easily recognize the importance of areal classification as statistics were different according to areal classification.

  • PDF

A Comparative Analysis of Areal Interpolation Methods for Representing Spatial Distribution of Population Subgroups (하위인구집단의 분포 재현을 위한 에어리얼 인터폴레이션의 비교 분석)

  • Cho, Daeheon
    • Spatial Information Research
    • /
    • v.22 no.3
    • /
    • pp.35-46
    • /
    • 2014
  • Population data are usually provided at administrative spatial units in Korea, so areal interpolation is needed for fine-grained analysis. This study aims to compare various methods of areal interpolation for population subgroups rather than the total population. We estimated the number of elderly people and single-person households for small areal units from Dong data by the different interpolation methods using 2010 census data of Seoul, and compared the estimates to actual values. As a result, the performance of areal interpolation methods varied between the total population and subgroup populations as well as between different population subgroups. It turned out that the method using GWR (geographically weighted regression) and building type data outperformed other methods for the total population and households. However, the OLS regression method using building type data performed better for the elderly population, and the OLS regression method based on land use data was the most effective for single-person households. Based on these results, spatial distribution of the single elderly was represented at small areal units, and we believe that this approach can contribute to effective implementation of urban policies.

The Estimation of Areal Rainfall Quantiles in Han River Basin (한강유역의 면적 확률강우량 산정에 관한 연구)

  • Kim, Gyeong-Deok;Go, Yeon-U;Heo, Jun-Haeng
    • Journal of Korea Water Resources Association
    • /
    • v.33 no.4
    • /
    • pp.419-426
    • /
    • 2000
  • It is very important to establish sufficiently long and reliable annual maximum rainfall data in estimating areal rainfall quantiles of Han River Basin. The data from 9 gauging stations measured by Korea Meteorological Administration may meet such a requirement, however the number of these data sets is too small to estimate overall areal rainfall quantiles in large basin such as Han River Basin. In order to solve such a problem, the space correlations of many sites' data measured by Korea Ministry of Construction and Transportation and Korea Water Resources Corporation (the number of sites is 59) were used for modification of rainfall measure density. And areal rainfall quantiles according to each sub-basin were estimated based on regression analysis.

  • PDF

Spatial Interpolation of Rainfall by Areal Reduction Factor (ARF) Analysis for Hancheon Watershed

  • Kar, Kanak Kanti;Yang, Sung Kee;Lee, Junho
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2015.05a
    • /
    • pp.427-427
    • /
    • 2015
  • The storm water management and drainage relation are the key variable that plays a vital role on hydrological design and risk analysis. These require knowledge about spatial variability over a specified area. Generally, design rainfall values are expressed from the fixed point rainfall, which is depth at a specific location. Concurrently, determine the areal rainfall amount is also very important. Therefore, a spatial rainfall interpolation (point rainfall converting to areal rainfall) can be solved by areal reduction factor (ARF) estimation. In mainland of South Korea, for dam design and its operation, public safety, other surface water projects concerned about ARF for extreme hydrological events. In spite of the long term average rainfall (2,061 mm) and increasing extreme rainfall events, ARF estimation is also essential for Jeju Island's water control structures. To meet up this purpose, five fixed rainfall stations of automatic weather stations (AWS) near the "Hancheon Stream Watershed" area has been considered and more than 50 years of high quality rainfall data have been analyzed for estimating design rainfall. The relationship approach for the 24 hour design storm is assessed based on ARF. Furthermore, this presentation will provide an outline of ARF standards that can be used to assist the decision makers and water resources engineers for other streams of Jeju Island.

  • PDF