• Title/Summary/Keyword: Spatial Overlay Analysis

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A Study on Extraction of the Topographical Parameters Using HEC-GEOHMS and DEM (HEC-GEOHMS와 DEM을 이용한 지형인자 추출에 관한 연구)

  • Lee, Jung-Min;Jeong, In-Ju;Kim, Sang-Yong
    • Journal of Korean Society for Geospatial Information Science
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    • v.11 no.1 s.24
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    • pp.39-44
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    • 2003
  • Recently, GIS has been increasing its applicability in water resource field. The GIS based modeling process can generally be used for extracting channel network and watershed delineation. Through the overlay analysis, the extracted channel network can be overlayed with topographic and landuse maps to generate the input files for running a hydrologic model. This lead to consider GIS as a tool which can include subjective factors of the model designers in hydrologic analysis. Therefore, this study has compared GIS based HEC-GEOHMS with the classical approach. In general, both approaches have similar results, however, HEC-GROHMS has showed some errors. Based on the results, a GIS based approach could be more effective method with better credibility to obtain input parameters from topographic information as subsequent efforts were made to lessen the errors.

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A Method to Measure Damage Areas on Railway Accidents by the HAZMATs types using GIS Spatial Analysis (GIS 공간 분석기법을 활용한 위험물질별 철도사고 피해규모 자동추출방안에 관한 연구)

  • Park, Min-Kyu;Kim, Si-Gon;Lee, Won-Tae
    • Journal of the Korea Safety Management & Science
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    • v.12 no.1
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    • pp.35-42
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    • 2010
  • Due to the industrialization and urbanization, the transport of hazardous materials increases, which rises possibilities in occurring prospective accidents in terms of hazardous material transport as well. This study applied the model developed from the previous research to analyze the scale of damage areas from the accidents related to hazardous material accidents, as well as suggested a method to measure automatically the scale of accident including casualties and environmental damage based on the guideline which suggests the quantities of hazardous materials exposed from an accident and was defined in the study of standardization for hazardous material classification. A buffering analysis technique of Geographic Information System (GIS) was applied for that. To apply the model which evaluates the scale of population and exposure to environment on each link, rail network, zones, rail accident data, rail freight trips, and locations of rivers etc were complied as a database for GIS analysis. In conclusion, a method to measure damage areas by the types of hazardous materials was introduced using a Clip and a Special Join technique for overlay analysis.

A Study of GIS-based Estimation of Pollutant Loads in Accordance with Spatial Landuse Variation - Focussing on Wangsook Watershed - (토지이용의 공간적 다양성에 따른 GIS 기반 오염부하 산정에 관한 연구 - 왕숙천 유역을 중심으로 -)

  • Kim, Kyoung-Soon;Kim, Kye-Hyun;Kwon, Oh-Jun
    • Journal of Environmental Impact Assessment
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    • v.14 no.5
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    • pp.305-315
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    • 2005
  • The scheme to classify pollution sources in Korean TMDL planning has been pointed out too much complex to implement practically because of requiring a wide range of items to be collected from a field. Within a deficient situation to collect field data, the mathematical scheme that focuses only on counting an uniform area ratio of the different land uses to estimate of pollutant loads from individual sub-catchments has been used without taking into account of the spatial characteristics of major land uses as well as the locations of pollution sources in each sub-catchment. It would cause to significant level of errors to estimate the pollution loads. Therefore, this study proposes a renovated scheme that can be adopted more easily to classify pollution sources in the watershed and reduce the estimation errors in the spatial distribution of pollution sources by introducing a spatial analysis based on digital land cover maps. In order to estimate a unit area to calculate the uniform pollution load, the pollution response unit area that is locating spatially at the same place and having same land use is identified through the application of GIS overlay technique. Unlikely existing conventional method to calculate the pollution load based on equal distribution of pollutants for each administrative boundary, it is assumed that the pollution load from household and livestock sources are generated and washed off from only residential areas. While, pollution from business population comes from commercial area and industrial load from wastewater discharge facilities are from industrial areas. From comparison of the calculated results from the existing the method and the proposed one, it is found that although the estimation of pollution load from sub-catchment in the case of the existing conventional method application results in negligible difference in total pollution amounts from the whole area of Wangsook watershed as a study area, significant difference of pollution load among sub-catchment in which pollution response unit areas are diverse, however, appears in the case of the application of the renovated scheme.

Development of Expert System for Land Use Suitability Analysis Using Quadtree Data Structures (Quadtree 자료구조를 이용한 적지분석 전문가시스템 개발)

  • Yoo, Hwan-Hee;Kim, Eui-Myoung
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.1 s.5
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    • pp.139-150
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    • 1995
  • The assessment/evaluation of land use suitability is an important part of land use planning. In this paper, we developed. The Expert System for a suitability analysis including the function of data storage, analysis, assessment and display by using Borland C++ Language and could suggest the following results in the suitability analysis to select a site for an industrial complex using this system. 1. With the increase in volume and variety of geo-spatial data now available, it has become necessary to find more efficient ways of storing this data. This report presents the Quadtree structure, as a method of gaining significant savings over conventional raster processing in data storage. 2. In order to get the criteria of suitability analysis, the opinions of specialists, administrative officers and citizens were collected by a questionnaire, and used to calculate the weight of geo-spatial data. Also, The Expert System, which we developed, was designed to do overlay and spatial analysis, as well as reflect the various opinions we collected in the questionnaire. The Expert System is expected to be used in other land use planning.

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Application Method of Satellite Image and GIS for Suitability of Black Locust Forest as Honey Plant Area (아까시나무 밀원식물단지 적지 선정을 위한 위성영상과 GIS의 응용기법)

  • Jo, Myung-Hee;Kim, Joon-Bum;Jo, Yun-Won;Baek, Seong-Ryul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.4 no.2
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    • pp.27-37
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    • 2001
  • Using satellite image and GIS, spatial distribution characteristics of black locust forest as honey plant area was identified and analyzed. Upon the result, the most suitable area for black locust forest was selected through the integration analysis of transparent overlay. The variables used for spatial analysis such as topography(elevation, aspect, slope), soil, drainage, distance from urban area, land use, meteorological elements were considered. Based on the suitability analysis, it was clarified that the integration of linear and factor combination technique is greatly efficient method for the most suitable area. In addition, Gokung, Imgo, Chungtong, Hwanam area were shown to be suitable in Young-chun Area. As the result of suitability analysis for honey plant area of black locust in Young-chun using satellite image and GIS, the present portion of potential distribution area was produced about 42.53%. The portion of most suitable area for honey plant area of black locust was about 26.77%. Finally, the total area for honey plant area of black locust in Young-chun came up to $15.79km^2$. Additionally, satellite image and GIS were expected to be significant tools for suitability analysis of honey plant complex area.

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Cluster Analysis of Car Parking Data, and Development of their Web Applications

  • Kubota, Takafumi;Hayashi, Takayuki;Tarumi, Tomoyuki
    • 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.

A Spatial Change Analysis of Water Quality Pollutant using GIS and Satellite Image (GIS와 위성영상을 이용한 수질 오염인자의 공간 변화 분석)

  • Jo, Myung-Hee;Kwon, Bong-Kyum;Bu, Ki-Dong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.3
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    • pp.60-70
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    • 1999
  • The purpose of this study is to analyze the spatial change of water quality pollutant in the upper-stream of Kumho River basin. For this purpose, it compared with ground survey data of water quality measurement, using GIS and Landsat TM image, and then constructed a database of water quality pollutants in the watershed by Arc/Info. Also the land cover classification maps of 1985 and 1997 were prepared using maximum likelihood classification. This study detected and analysed the classified images to produce the area of land cover change per sub-basin. In addition, choropleth maps were prepared with spatial change value of water quality pollutants, and overlay analysis was carried out with weight score for each layer. The results of this study revealed that population, animals and fruit orchards were main factors in the spatial change of water pollution of Kumho River basin. The Comparision of pollutions by sub-basins showed a high pollution value in Daechang-chun and Omok -chun stream which follows through the urban area.

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A Spatial Decision Support System for Establishing Urban Ecological Network ; Based on the Landscape Ecology Theory (도시 생태네트워크 설정을 위한 공간의사결정지원체계에 관한 연구 ; 경관생태학 이론을 기반으로)

  • Oh, Kyu-Shik;Lee, Dong-Woo;Jung, Seung-Hyun;Park, Chang-Suk
    • Spatial Information Research
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    • v.17 no.3
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    • pp.251-259
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    • 2009
  • As a result of the current trend towards promoting conservation of the ecosystem, there have been various studies conducted to determine ways to establish an ecological network. The development of analytical methods and an environmental database of GIS has made the creation of this network more efficient. This study focuses on the development of an urban spatial decision support system based on 'Landscape Ecology Theory'. The spatial decision support system suggested in this study consists of four stages. First, landscape patch for the core areas, which are major structures of the ecological network, was determined using the GIS overlay method. Second, a forest habitat was investigated to determine connectivity assessment. Using the gravity model, connectivity assessment at the habitat forest was conducted to select the needed connecting area. Third, the most suitable corridor routes for the eco-network were presented using the least-cost path analysis. Finally, a brief investigation was conducted to determine the conflict areas between the study result and landuse. The results of this study can be applied to urban green network planning. Moreover, the method developed in this study can be utilized to control urban sprawl, promote biodiversity.

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Digital Divide in Riyadh Neighborhoods: A Spatial Analysis

  • Rawan, Almutlaq;Shuruq, Alshamrani;Ohoud, Alhaqbani;Fatimah, Altamimi;Ghadah, Alammaj;Omer, Alrwais
    • International Journal of Computer Science & Network Security
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    • v.23 no.1
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    • pp.17-24
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    • 2023
  • The objective of this paper is to use Geographical Information Systems for identifying Digital Divide in Riyadh Neighborhoods, Saudi Arabia. Geo-database was created that includes Streets, Neighborhoods, ICT Access Data and Coverage Map for Riyadh. We used QGIS and overlay for analysis, intersection selected as tool for this paper. The results indicate that after analyzing the use of information communication technology in all regions of the Kingdom it turns that Riyadh, Ash Sharqiyyah and Makkah in average with percentage 50%, While Al Jawf, Al Madinah, and Najran are the least with percentage 42%. Then we focused on Riyadh to analyze the digital divide because it is the capital of Saudi Arabia and occupations the highest percent of communications towers in the KSA due to population density. Regarding coverage of the 4G, the neighborhoods at the center have recorded very high coverage score. While neighborhoods at the edges of the city have low values of coverage score. Same for 3G, it is more intense in the center and the coverage percentage is higher than 4G. For 2G we found it had the highest coverage compared to 3G or 4G

The Site Analysis for Crop Cultivation Using GIS-Based AHP Method (GIS 기반 AHP 기법을 이용한 작물재배 적지분석)

  • Kim, Tae Jun;Lee, Geun Sang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4D
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    • pp.695-702
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    • 2006
  • In GIS-based Spatial Decision-making Support System (SDSS), the Boolean logic by conventional simple overlay method contains two problems. One is losing lots of information in analysis process, the other is unable to reflect of weighting values between evaluated items. Therefore, evaluation system as Analytic Hierarchy Process (AHP) needs to improve these problems effectively. The purpose of this study is to provide the benefit of AHP method and GIS spatial analysis in site analysis for crop cultivation. First, the weighting value of AHP for topography, distribution grade of water, property of soil and slope items are evaluated throughout survey to experts of soil, crop and agricultural management fields. On the basis of these weighting value of AHP by items, site suitability analysis for black raspberry cultivation is performed. To estimate the benefit of AHP method, the current cultivating map of black raspberry is constructed in Ssangchi-myeon district. In comparison with site analysis of Boolean logic, site analysis of AHP method shows more realistic.