• Title/Summary/Keyword: OVERLAY ANALYSIS

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Analysis of the Emergency Medical Service Area Using GIS: the Case of Seoul (GIS를 이용한 응급의료 진료권 분석: 서울시를 사례로 하여)

  • 이희연;박미영
    • Spatial Information Research
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    • v.12 no.2
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    • pp.193-209
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    • 2004
  • The purpose of this study is to analyze the service area of emergency medical centers using GIS-based spatial analysis methods in Seoul, focusing on the behaviour of patients on the choosing of emergency centers. For this analysis, six emergency centers were selected to collect data for the information on the addresses of patients from September to November hi 2003. Analysis on the service area, which was carried out by measuring the distribution of patients in terms of distance from emergency medical centers, clearly reveals that the majority of patients was located within or adjacent districts at the emergency medical center. However, the size of the primary service area f3r six emergency medical centers was much different, implying that the decision to visit specific emergency medical center by patients was closely related to the size, perception, and preference of the emergency medical center. Based on the results of the spatial characteristics of emergency medical service area, this research tries to construct the surface map of the emergency medical service level supplied by 32 regional emergency medical centers located in Seoul. Considering the levels of infrastructure for emergency medical centers, the coverage for the degree of supply of emergency medical service by each emergency medical center was constructed in terms of a distance decaying in the distribution of patients from emergency medical center imposing different weights on distance bands. Spatial overlay utilizing map algebra function was performed in order to calculate total supply level of emergency service. The results clearly show that spatial inequality exists in the supply levels of the emergency medical service among local areas of Seoul.

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An Assessment of Coastal Area Using Geographic Information Systems and Multi-Criteria Analysis (지리정보시스템(GIS)과 다기준 분석법(MCA)을 적용한 연안지역 평가)

  • Choi, Hee-Jung;Park, Jung-Jae;Hwang, Chul-Sue
    • Journal of the Korean association of regional geographers
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    • v.13 no.2
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    • pp.143-155
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    • 2007
  • There are many conflicts or interests among various stakeholders on the development of the coastal area. The integrated methodology, which is reflective of physical conditions, socio-economic circumstances, and people's sense of values, is thus needed to solve the problems. In this study, geographical information systems(GIS) and analytic hierarchy process(AHP) that arc one of multi-criteria analysis methodologies are loosely coupled to develop better analytic procedures for coastal assessment. Socio-economic and environmental parameters of the study area, Hampyung Bay area, are converted to a GIS system-applicable format, while AHP is used to assess the relative importance level of each parameter by calculating weighting factors. After standardizing and rasterizing spatial data from various sources. the weighting factors are applied to produce the layers for each parameter. Map algebra and overlay analyses are used to create the final layer according to the decision making logic or model proposed here. Cell values of that layer could be considered as spatial alternatives. In addition to this finding, the flexibility with the weighing factors enable decision-makers to understand the procedures and alternatives in relevance with selective strategies for coastal management.

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Development of an Image Processing System for the Large Size High Resolution Satellite Images (대용량 고해상 위성영상처리 시스템 개발)

  • 김경옥;양영규;안충현
    • Korean Journal of Remote Sensing
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    • v.14 no.4
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    • pp.376-391
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    • 1998
  • Images from satellites will have 1 to 3 meter ground resolution and will be very useful for analyzing current status of earth surface. An image processing system named GeoWatch with more intelligent image processing algorithms has been designed and implemented to support the detailed analysis of the land surface using high-resolution satellite imagery. The GeoWatch is a valuable tool for satellite image processing such as digitizing, geometric correction using ground control points, interactive enhancement, various transforms, arithmetic operations, calculating vegetation indices. It can be used for investigating various facts such as the change detection, land cover classification, capacity estimation of the industrial complex, urban information extraction, etc. using more intelligent analysis method with a variety of visual techniques. The strong points of this system are flexible algorithm-save-method for efficient handling of large size images (e.g. full scenes), automatic menu generation and powerful visual programming environment. Most of the existing image processing systems use general graphic user interfaces. In this paper we adopted visual program language for remotely sensed image processing for its powerful programmability and ease of use. This system is an integrated raster/vector analysis system and equipped with many useful functions such as vector overlay, flight simulation, 3D display, and object modeling techniques, etc. In addition to the modules for image and digital signal processing, the system provides many other utilities such as a toolbox and an interactive image editor. This paper also presents several cases of image analysis methods with AI (Artificial Intelligent) technique and design concept for visual programming environment.

A Study on the Deriving of Areas of Concern for Crime using the Mental Map (멘탈 맵을 이용한 범죄발생 우려 지역 도출에 관한 연구)

  • Park, Su Jeong;Shin, Dong Bin
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.3
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    • pp.177-188
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    • 2019
  • Recently, citizens are feeling anxious as 'Motiveless Crime' increases. The quality of citizens life is degraded and the degree of crime fear is increasing. In this study, based on various variables related to crime other than actual crime occurrence status, crime occurrence points (point line polygon) felt by citizens are created by using mental map methodology. And the purpose of this study is to derive the area of concern for crime through spatial overlap analysis using kernel density estimation analysis. It also uses spatial overlay analysis using kernel density estimation to derive areas of concern for crime occurrence. As a result, the local residents' request point and the areas of concern for crime were overlapped. In addition, the mental map indicating the fear of crime was constructed by mapping mainly the areas between the facilities, the non-construction area such as the narrow area, the security CCTV, the streetlight. This study is meaningful in that it tried to derive a crime occurrence concern area by using mental map method unlike the previous study related to crime. The results of this study, such as mental map, could be used in various fields such as construction of fragile crime map, guideline of crime prevention through environment design.

An Assessment of Urban Amenity using Physical Environmental Factors (물리적 환경인자를 활용한 도시의 쾌적성 평가)

  • Lee, Woo-Sung;Gwak, Haeng-Goo;Jung, Sung-Gwan;Park, Kyung-Hun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.1
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    • pp.169-182
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    • 2007
  • The purpose of this study is to assess the urban amenity on physical environmental factors, and to verify the effectiveness of the amenity map using correlation analysis of the environmental quality. The physical environmental factors were set to 4 items of green space, landscape, water environment and land use, and the items were composed of 11 detail factors. Based on the factors, GIS maps were constructed and the amenity map was produced using overlay analysis. The results of this study are as follow; the proportion of 1~2 ranks was 40.8% of total area around Dalseong-gun, Dong-gu, Suseong-gu. The lower 6~7 ranks in the amenity assessment was 5.7% of total area around Jung-gu, Seo-gu, Dalseo-gu. According to the results of correlation analysis between the amenity and environmental observed data, $SO_2$ among the air pollution material had a negative correlation with amenity(r=-0.649, p<0.05). In case of water pollution, TN and TP had the negative correlations with amenity (r=-0.643, P<0.01; r=0.642, p<0.01).

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The Performance Analysis of Diamond Grinding for Existing Concrete Pavement (기존 콘크리트 포장의 성능 향상을 위한 다이아몬드 그라인딩 공법의 초기 공용성 평가)

  • Jung Jong-Duck;Ryu Sung-Woo;Han Seung-Hwan;Cho Yoon-Ho
    • International Journal of Highway Engineering
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    • v.8 no.3 s.29
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    • pp.77-88
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    • 2006
  • The maintenance / repair of concrete pavements has become an issue as a result of increasing of concrete pavements' service year. Asphalt overlay is applied to the concrete pavements after partial repairs on all occasions. This thesis discusses the application standard, evenness, skid resistance, noise, economical efficiency, extension of life span, etc. of diamond grinding, a method of maintenance about concrete pavements. Based on this, it was applied to the field and measured the performance. It was measured the longitudinal evenness of before and after the construction through measurement equipment. and surveyed the skid resistance the each lane classified using the SN standard value. In case of noise, it is selected the kind of vehicle, velocity, then measured the noise between control and constructed site. In addition, it is evaluated the average texture depth. As a result of the analysis, longitudinal evenness is improved about $6{\sim}40%$, skid resistance is improved 66% at first section,37% at second section. Noise is reduced 3.4dB average, and average texture depth is 79% deeper than control section. Therefore, it can be concluded that diamond grinding is suitable as maintenance / repair method of concrete pavements.

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Study for Building Ecological Network in East-North Asia (동북아 생태네트워크 구축을 위한 방안 고찰)

  • Jeon, Seong-Woo;Lee, Moung-Jin;Kang, Byung-Jin;Shin, Ji-Young
    • Journal of Environmental Policy
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    • v.8 no.3
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    • pp.1-26
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    • 2009
  • In the 1990s, when the viewpoint that an ecosystem is a single network within a specific region was adopted, the preservation and management of natural ecosystems was proposed. With regard to Northeast Asia, the expansion of trans-boundary pollution due to rapid development and the swift destruction of the natural environment emphasize the necessity for environmental cooperation. The Northeast Asia region made up of South Korea, North Korea, three northeastern prefectures in China, the Russian far-east, and parts of Mongolia were selected to be analyzed for an ecological network. The significance of this study lies in the development of a methodology for building a Northeast Asian ecological network through the use of satellite images. Regarding the methods of analysis, stable habitats for four priority species were selected to be performed using overlay analysis. The result of the analysis of the ecological networks in the whole Northeast Asia region showed that there were key areas partly dispersed in the Korean Peninsula, but whether the key areas would be maintained in the long term is unknown. As for China, key areas were concentrated in the border areas around the Tumen River and in parts of the three northeastern prefectures. Russia had wide-ranging areas that could function as stable habitats for most species. As a result of the actual conditions of the ecological networks, most of the Northeast Asia region, including the Korean Peninsula, was in poor condition, requiring appropriate measures and their operation as soon as possible. Also, it was revealed that further investigation and research was necessary for border areas that were identified to be key areas.

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Validity Evaluation of Real Time Mobile GIS combined with PDA in University Building Facility Management (대학시설물 관리W떠 PDA기반의 실시간 Mobile GIS 도입 타당성 평가)

  • 정지훈;엄정섭
    • Spatial Information Research
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    • v.11 no.1
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    • pp.41-60
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    • 2003
  • It is noted that the paper mapping system for University Building Facility has many limitations in terms of data maintenance, real-time GIS data acquisition, and economic efficiency. The aim of this research was to evaluate an operational potential of an on site real-time mobile GIS technique to resolve the problem faced in the university. The idea is based upon the recent trends in the field of 'Telecommunication and Information Technology' that uses a PDA (personal Digital Assistants), wireless network computing, mobile computing, etc. A real time mobile GIS approach has been adopted, in which a PDA is linked to a wireless internet and field workers record data on the computer at the site and analyse data on site. While there should be a considerable number and variety of factors associated with real-time mobile GIS quality, this research focuses on three criteria that are identified as fundamental to customer requirements; (1) data quarry (2) spatial analysis (3) real-time GIS database building. 'Art--empirical study for a case study facility has been conducted to confirm the validity for the system. The system has been checked experimentally, enabled the field users to quarry the data required simply and execute spatial analysis (buffer, overlay etc.,) accommodating versatile alternatives on the site. Detailed visual maps can be generated over large areas quickly and easily. The PDA interface, in particular, were ideally suited for field users to interactively displaying positional information with attribute data. This system has shown to be quite convenient to maintaining a highly reliable database since it could playa crucial role in documenting at real-time basis temporal and spatial changes occurred in the facilities. It is anticipated that this research output will greatly serve to introduce the reliable and cost-effective facility mapping system in the university by overcoming serious constraints suffered from the past non-real time mobile GIS approach.

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A Study on Development of a GIS based Post-processing System of the EFDC Model for Supporting Water Quality Management (수질관리 지원을 위한 GIS기반의 EFDC 모델 후처리 시스템 개발 연구)

  • Lee, Geon Hwi;Kim, Kye Hyun;Park, Yong Gil;Lee, Sung Joo
    • Spatial Information Research
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    • v.22 no.4
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    • pp.39-47
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    • 2014
  • The Yeongsan river estuary has a serious water quality problem due to the water stagnation and it is imperative to predict the changes of water quality for mitigating water pollution. EFDC(Environmental Fluid Dynamics Code) model was mainly utilized to predict the changes of water quality for the estuary. The EFDC modeling normally accompanies the large volume of modeling output. For checking the spatial distribution of the modeling results, post-processing for converting of the output is prerequisite and mainly post-processing program is EFDC_Explorer. However, EFDC_Explorer only shows the spatial distribution of the time series and this doesn't support overlay function with other thematic maps. This means the impossible to the connection analysis with a various GIS data and high dimensional analysis. Therefore, this study aims to develop a post-processing system of a EFDC output to use them as GIS layers. For achieving this purpose, a editing module for main input files, and a module for converting binary format into an ASCII format, and a module for converting it into a layer format to use in a GIS based environment, and a module for visualizing the reconfigured model result efficiently were developed. Using the developed system, result file is possible to automatically convert the GIS based layer and it is possible to utilize for water quality management.

Value Assessment for Inland Wetlands according to Ecological Geographic Distribution (생태지리적 입지에 따른 내륙습지 가치평가)

  • Lee, Jung-Hwan;Im, Ran-Young;Lee, Gwan-Gyu;Park, Hyun-Chul
    • Journal of Wetlands Research
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    • v.18 no.4
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    • pp.456-464
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    • 2016
  • Korea established an inventory of 1,916 sites of inland wetlands during a nationwide investigation from 2000 to 2010. If inland wetlands is included in or near various protected areas designated by the government, it can be selected as a wetland to be managed with priority. This study evaluated the aspect of management of inland wetlands by analyzing the correlation between locations of national protected areas and inland wetlands. As a result, it was shown that a considerable percentage of current inland wetland was located in areas that were designated and managed as protected areas by the government, as they had a high value of natural environment protection (527 sites, 31.61 %). When the range was widened to a radius of 1 km for protected areas, 959 sites were included and 57.53 % of sites were located in or nearby the protected areas. Among them, 46.79 % of sites were distributed up to or within a 1 km radius of waterside areas and rivers; it accounted for 81.33 % of wetlands located in protected areas. Therefore, it was found that locations of current inland wetlands were mostly in contact with rivers. The results of overlay analysis were classified into high, medium and low; the correlation of location with inland wetlands was analyzed through the analysis of separation distance of various protected areas. The number of wetlands located in areas of a 'high' value of protection was 998 (59.87 %); 289 sites (17.34 %) were distributed in areas of a 'low' value of protection. This implies that these wetlands are located in artificial areas and are more exposed to environmental pressures. Thus, these wetlands could be determined as inland wetlands, which we considered for the establishment of measures to prevent damage.