• Title/Summary/Keyword: GIS based

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The Spatial Inequalities in Education, Seoul (교육의 공간 불평등 연구)

  • Jung, Jae-Hun;Kim, Kyung-Min
    • Journal of the Economic Geographical Society of Korea
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    • v.17 no.2
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    • pp.385-401
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    • 2014
  • This research analyses spatial and temporal characteristics of the academic performances of high school students by using all 2,065,166 SAT scores for 3 years. The spatial inequalities in Seoul are analysed by DBMS and GIS. Based on three-year raw data of Korean SAT scores, the spatial and temporal characteristics of academic performances are scrutinized: 868,029 SAT scores cases of 2000 academic year on Novemver 17, 1999, 609,258 cases in 2005 academic year on November 17, 2004 and 587,890 cases in 2009 on November 13. The result shows that there are significant spatial disparities of the level of academic performance in Seoul by Gu level, also indicating that the disparities are getting wider over the course of time. The widening disparities by Gu level means that educational spatial inequality is intensified in spite of the increasing overall trend of academic performance of Seoul. It is also notable that disparities between regions are distinctive, while those in regions are not significant and sustained constant as time flows.

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Availability Evaluation For Generation Orthoimage Using Photogrammetric UAV System (사진측량용 UAV 시스템을 이용한 정사영상 제작 및 활용성 평가)

  • Shin, Dongyoon;Han, Jihye;Jin, Yujin;Park, Jaeyoung;Jeong, Hohyun
    • Korean Journal of Remote Sensing
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    • v.32 no.3
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    • pp.275-285
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    • 2016
  • This study analyzes the accuracy of ortho imagery based on whether camera calibration performed or not, using an unmanned aerial vehicle which equipped smart camera. Photgrammetric UAV system application was developed and smart camera performed image triangulation, and then created image as ortho imagery. Image triangulation was performed depending on whether interior orientation (IO) parameters were considered or not, which determined at the camera calibration phase. As a result of the camera calibration, RMS error appeared 0.57 pixel, which is more accurate compared to the result of the previous study using non-metric camera. When IO parameters were considered in static experiment, the triangulation resulted in 2 pixel or less (RMSE), which is at least 200 % higher than when IO parameters were not considered. After generate ortho imagery, the accuracy is 89% higher when camera calibration are considered than when they are not considered. Therefore, smart camera has high potential to use as a payload for UAV system and is expected to be equipped on the current UAV system to function directly or indirectly.

A Study on Designation and Management of Groundwater Conservation Area Using Groundwater Classification Map (지하수 분류도 작성에 의한 서울시 지하수 보전지구 선정\ulcorner관리 방안 연구)

  • 김윤종;이석민;원종석;이성복
    • Journal of Soil and Groundwater Environment
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    • v.6 no.4
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    • pp.97-112
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    • 2001
  • The Section 12 of Groundwater Law stipulates that groundwater conservation zone should be regulated by the designation of conservation area and development restricted area, The most important policy for groundwater conservation and protection is to estimate and designate groundwater conservation zone. The groundwater classification map is utilized to determine the prime groundwater conservation areas, which delineate the first and the second ranked conservation areas of the map. According to the classification method of the Ministry of Construction and Transportation in 2000, groundwater quality for groundwater classification is classified with 4 levels based on the following conditions : (1) the present groundwater quality; (2) the potential usage as drinking water at present and in the future; (3) hydrogeological characteristics, and (4) the existence of pollution sources and activities. Throughout the initial analysis, the groundwater conservation areas are represented about 57.1$\textrm{km}^2$ in the groundwater classification map, which is 9.4% of Seoul Metropolitan Area. The management guidelines for groundwater conservation area are also developed referring to Cheju Province Groundwater Conservation Management Project and the guidelines by the Ministry of Construction and Transportation. But the specific administration and detailed technical survey should be prepared to efficiently manage the groundwater conservation area.

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Application of Snowmelt Parameters and the Impact Assessment in the SLURP Semi-Distributed Hydrological Model (준 분포형 수문모형 SLURP에서 융설매개변수 적용 및 영향 평가)

  • Shin, Hyung-Jin;Kim, Seong-Joon
    • Journal of Korea Water Resources Association
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    • v.40 no.8
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    • pp.617-628
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    • 2007
  • The purpose of this paper is to prepare snowmelt parameters using RS and GIS and to assess the snowmelt impact in SLURP (Semi-distributed Land Use-based Runoff Process) model for Chungju-Dam watershed $(6,661.5km^2)$. Three sets of NOAA AVHRR images (1998-1999, 2000-2001, 2001-2002) were analyzed to prepare snow-related data of the model during winter period. Snow cover areas were extracted using 1, 3 and 4 channels, and the snow depth was spatially interpolated using snowfall data of ground meteorological stations. With the snowmelt parameters, DEM (Digital Elevation Model), land cover, NDVI (Normalized Difference Vegetation Index) and weather data, the model was calibrated for 3 years (1998, 2000, 2001), and verified for 1 year (1999) using the calibrated parameters. The average Nash-Sutcliffe efficiencies for 4 years (1998-2001) discharge comparison with and without snowmelt parameters were 0.76 and 0.73 for the full period, and 0.57 and 0.19 for the period of January to May. The results showed that the spatially prepared snow-related data reduced the calibration effort and enhanced the model results.

Development and Application of Diffusion Wave-based Distributed Runoff Model (확산파에 기초한 분포형 유출모형의 개발 및 적용)

  • Lee, Min-Ho;Yoo, Dong-Hoon
    • Journal of Korea Water Resources Association
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    • v.44 no.7
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    • pp.553-563
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    • 2011
  • According to the improvement of computer's performance, the development of Geographic Information System (GIS), and the activation of offering information, a distributed model for analyzing runoff has been studied a lot in recently years. The distribution model is a theoretical and physical model computing runoff as making target basin subdivided parted. In the distributed model developed by this study, the volume of runoff at the surface flow is calculated on the basis of the parameter determined by landcover data and a two-dimensional diffusion wave equation. Most of existing runoff models compute velocity and discharge of flow by applying Manning-Strickler's mean velocity equation and Manning's roughness coefficient. Manning's roughness coefficient is not matched with dimension and ambiguous at computation; Nevertheless, it is widely used in because of its convenience for use. In order to improve those problems, this study developed the runoff model by applying not only Manning-Strickler's equation but also Chezy's mean velocity equation. Furthermore, this study introduced a power law of exponential friction factor expressed by the function of roughness height. The distributed model developed in this study is applied to 6 events of fan-shape basin, oblong shape test basin and Anseongcheon basin as real field conditions. As a result the model is found to be excellent in comparison with the exiting runoff models using for practical engineering application.

Spatial Structure and Historical Change of Cemeteries in Seattle, USA (시애틀 공동묘지의 공간적 구조와 역사적 변화 양상)

  • Kim, Chung Ho
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.3
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    • pp.36-45
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    • 2018
  • Cemeteries in the United States are frequently observed near residential areas in cities even though they are spaces for the dead. However, it has not been fully studied when and how cemeteries were formed in the process of urbanization. Thus, this research aimed to investigate the spatial structure and historical change of cemeteries in Seattle due to urbanization, focusing on the contextual relationship between cemeteries and the surroundings according to two time periods: the early formation period of cemeteries in Seattle and the current period. For this, a mixed method was taken in this paper that combined historical analysis based on old references and historic maps with cluster analysis using GIS. In conclusion, the research found that early cemeteries of Seattle in downtown areas were introduced as by-products of urban formation, but the cemeteries in the suburbs were established ahead of urban growth and neighborhood development. In addition, Seattle's cemeteries not only showed a similar locational pattern to Seattle's shopping centers, but also were positively associated with population distribution given the Hot Spot Analysis. In other words, Seattle's cemeteries were originally located in rural areas, but later came to be located in urban areas, sustaining the landscape of American rural cemeteries.

The Effects of Urban Park and Vegetation on Crime in Seoul and Its Planning Implication to CPTED (CPTED 요소로써 서울시 공원·녹지의 효과와 계획적 함의)

  • Cho, Min-gyun;Park, Chan;Jang, Jeong-in
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.3
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    • pp.27-35
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    • 2018
  • In the mandatory application of the CPTED, only negative parts of urban parks and vegetation were reflected. Therefore, this study tries to present the positive effects of urban parks and vegetation. The purpose of this study is to demonstrate the effects of urban parks and vegetation on crime occurrence and to suggest the planning implications of this to CPTED based on theory related to crime, environmental psychology, and crime occurrence analysis. This study used the crime occurrence data of Seoul, NDVI, population, distance from urban park, floating population, and the like. This study collected data from the Statistics Korea, the local government, and Landsat 8 satellite images provided by the USGS and created data of environmental variables and social variables by district using ArcGIS and statistical program. Literature analysis, correlation analysis, regression analysis, and geographically weighted regression were used to determine the relationship between crime occurrence and environmental variables, and to discuss its implication. It was found that crime occurrence has a relationship with the total population (${\beta}=.663$), the number of amusement facilities (${\beta}=.447$) and the area of a police station jurisdiction (${\beta}=.395$). This confirms that a crime rate is low when the floating population is large (${\beta}=-.241$) and vegetation vitality is high (NDVI, ${\beta}=-.281$). Vegetation vitality (NDVI) is effective in lowering violence through psychological stabilization, strengthening territoriality and improving regional image. The implications for the allocation of urban park and vegetation, program and management plan of urban park and vegetation to reduce crime occurrence have therefore been presented.

Assessment of Landslide Susceptibility using a Coupled Infinite Slope Model and Hydrologic Model in Jinbu Area, Gangwon-Do (무한사면모델과 수리학적 모델의 결합을 통한 강원도 진부지역의 산사태 취약성 분석)

  • Lee, Jung Hyun;Park, Hyuck Jin
    • Economic and Environmental Geology
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    • v.45 no.6
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    • pp.697-707
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    • 2012
  • The quantitative landslide susceptibility assessment methods can be divided into statistical approaches and geomechanical approaches based on the consideration of the triggering factors and landslide models. The geomechanical approach is considered as one of the most effective approaches since this approach proposes physical slope model and considers geomorphological and geomechanical properties of slope materials. Therefore, the geomechanical approaches has been used widely in landslide susceptibility analysis using the infinite slope model as physical slope model. However, the previous studies assumed constant groundwater level for broad study area without the consideration of rainfall intensity and hydraulic properties of soil materials. Therefore, in this study, landslide susceptibility assessment was implemented using the coupled infinite slope model with hydrologic model. For the analysis, geomechanical and hydrualic properties of slope materials and rainfall intensity were measured from the soil samples which were obtained from field investigation. For the practical application, the proposed approach was applied to Jinbu area, Gangwon-Do which was experienced large amount of landslides in July 2006. In order to compare to the proposed approach, the previous approach was used to analyze the landslide susceptibility using randomly selected groundwater level. Comparison of the results shows that the accuracy of the proposed method was improved with the consideration of the hydrologic model.

Spatial-temporal Assessment and Mapping of the Air Quality and Noise Pollution in a Sub-area Local Environment inside the Center of a Latin American Megacity: Universidad Nacional de Colombia - Bogotá Campus

  • Fredy Alejandro, Guevara Luna;Marco Andres, Guevara Luna;Nestor Yezid, Rojas Roa
    • Asian Journal of Atmospheric Environment
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    • v.12 no.3
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    • pp.232-243
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    • 2018
  • The construction, development and maintenance of an economically, environmentally and socially sustainable campus involves the integration of measuring tools and technical information that invites and encourages the community to know the actual state to generate positive actions for reducing the negative impacts over the local environment. At the Universidad Nacional de Colombia - Campus $Bogot{\acute{a}}$, a public area with daily traffic of more than 25000 people, the Environmental Management Bureau has committed with the monitoring of the noise pollution and air quality, as support to the campaigns aiming to reduce the pollutant emissions associated to the student's activities and campus operation. The target of this study is based in the implementation of mobile air quality and sonometry monitoring equipment, the mapping of the actual air quality and noise pollution inside the university campus as a novel methodology for a sub-area inside a megacity. This results and mapping are proposed as planning tool for the institution administrative sections. A mobile Kunak$^{(R)}$ Air & OPC air monitoring station with the capability to measure particulate matter $PM_{10}$, $PM_{2.5}$, Ozone ($O_3$), Sulfur Oxide ($SO_2$), Carbon Monoxide (CO) and Nitrogen Oxide ($NO_2$) as well as Temperature, Relative Humidity and Latitude and Longitude coordinates for the data georeferenciation; and a sonometer Cirrus$^{(R)}$ 162B Class 2 were used to perform the measurements. The measurements took place in conditions of academic activity and without it, with the aim of identify the impacts generated by the campus operation. Using the free code geographical information software QGIS$^{(R)}$ 2.18, the maps of each variable measured were developed, and the impacts generated by the operation of the campus were identified qualitative and quantitively. For the measured variables, an increase of around 21% for the $L_{Aeq}$ noise level and around 80% to 90% for air pollution were detected during the operation period.

Production and Analysis of Digital Climate Maps of Evapotranspiration Using Gridded Climate Scenario Data in Korean Peninsula (격자형 기후변화 시나리오 자료를 활용한 한반도의 증발산량 전자 기후도 생산 및 분석)

  • Yoo, Byoung Hyun;Lee, Kyu Jong;Lee, Byun Woo;Kim, Kwang Soo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.19 no.2
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    • pp.62-72
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    • 2017
  • Spatio-temporal projection of evapotranspiration over croplands would be useful for assessment of climate change impact and development of adaptation strategies in agriculture. Potential evapotranspiration (PET) and dryness index (DI) during rice growing seasons were calculated using climate change scenario data provided by the National Institute of Meteorological Research (NIMR). A data processing tool for gridded climate data files, readGrADSWrapper, was used to calculate PET and DI during the current (1986-2005) and future (2006-2100) periods. Scripts were written to implement the formulas of PET and DI in R, which is an open source statistical data analysis tool. Evapotranspiration in rice fields ($PET_{Rice}$) was also determined using R scripts. The Spatio-temporal patterns of PET differed by regions in Korean Peninsula under current and future climate conditions. Overall, PET and $PET_{Rice}$ tended to increase throughout the $21^{st}$ century. Those results suggested that region-specific water resource managements would be needed to minimize the risk of water loss in the regions where considerable increases in PET would occur under the future climate conditions. For example, a number of provinces classified as a humid region were projected to become a sub-humid region in the future. The Spatio-temporal assessment of water resources based on PET and DI would help the development of climate change adaptation strategies for rice production in the 21st century. In addition, the studies on climate change impact would be facilitated using specialized data tools, e.g., readGrADSWrapper, for geospatial analysis of climate data.