• Title/Summary/Keyword: Geographic survey

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Assessing the Spatial Distribution of Perfluorooctanoic Acid Exposure via Public Drinking Water Pipes Using Geographic Information Systems

  • Vieira, Veronica;Hoffman, Kate;Fletcher, Tony
    • Environmental Analysis Health and Toxicology
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    • v.28
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    • pp.9.1-9.5
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    • 2013
  • Objectives Geographic Information Systems (GIS) is a powerful tool for assessing exposure in epidemiologic studies. We used GIS to determine the geographic extent of contamination by perfluorooctanoic acid, C8 (PFOA) that was released into the environment from the DuPont Washington Works Facility located in Parkersburg, West Virginia. Methods Paper maps of pipe distribution networks were provided by six local public water districts participating in the community cross-sectional survey, the C8 Health Project. Residential histories were also collected in the survey and geocoded. We integrated the pipe networks and geocoded addresses to determine which addresses were serviced by one of the participating water districts. The GIS-based water district assignment was then compared to the participants' self-reported source of public drinking water. Results There were a total of 151,871 addresses provided by the 48,800 participants of the C8 Health Project that consented to geocoding. We were able to successfully geocode 139,067 (91.6%) addresses, and of these, 118,209 (85.0%) self-reported water sources were confirmed using the GIS-based method of water district assignment. Furthermore, the GIS-based method corrected 20,858 (15.0%) self-reported public drinking water sources. Over half (54%) the participants in the lowest GIS-based exposure group self-reported being in a higher exposed water district. Conclusions Not only were we able to correct erroneous self-reported water sources, we were also able to assign water districts to participants with unknown sources. Without the GIS-based method, the reliance on only self-reported data would have resulted in exposure misclassification.

A Study on the Construction of 3D GIS DB by LiDAR (LiDAR에 의한 3차원 GIS DB 구축에 관한 연구)

  • Yoon, Hee-Cheon;Park, Joon-Kyu
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.2
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    • pp.172-183
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    • 2007
  • Recently geospatial information has used widely in many areas such as effective use and management of national land, establishment of city planning, managements of environments and disasters, etc. But present digital map is not suitable for nowadays because of delay of information renewal and changes of topography. In this study, GIS DB construction method was researched through the process of extracting main vector layers such as buildings, roads, contours, etc. from LiDAR data. In order to analyze accuracies of constructed data, the digital topographic maps of 1:1000 scale which were produced by Korea National Geographic Information Institute(NGI) and results of GPS survey were used. Effective DB construction method was suggested through comparing with existing GIS DB construction methods.

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Inundation Analysis on the Flood Plain in Ungauged Area Using Satellite Rainfall and Global Geographic Data: In the case of Tumen/Namyang Area in Duman-gang(Riv.) (위성강우와 글로벌 지형 자료를 이용한 미계측 지역 홍수터 침수모의 : 두만강 도문/남양 지역을 중심으로)

  • CHOI, Yun-Seok;KIM, Joo-Hun;KIM, Ji-Sung
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.1
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    • pp.51-64
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    • 2020
  • The purpose of this study is to present a method for quantitative analysis of flooding at the flood plain in an ungauged area using satellite rainfall and global geographic data. For this, flooding of the Tumen/Namyang area in the Duman-gang(Riv.) was simulated and the flood conditions were quantitatively analyzed. The IMERG data, a rainfall data derived from satellite images, was used as rainfall data. The GRM model was applied to the watershed runoff simulation, and the G2D model was applied to the flooding simulation of the Tumen/Namyang area. Flood event caused by Typhoon Lionrock in August 2016 was applied. Recorded peak discharge of the Tumen/Namyang region was used to verify the runoff simulation results. To verify the result of the inundation simulation, the flood situation collected through field survey and satellite image data before and after the flood were used. The peak flow rates by the runoff simulation and flood record were 7,639㎥/s and 7,630㎥/s, respectively, with a relative error of about 0.1%. In the flood simulation, the results were similar to the flooding ranges identified in the survey data and satellite images. And the changes of flooding depth and flooding time in the flood plain in Tumen/Namyang area could also be assessed. The methods and results of this study will be useful for the quantitative assessment of floods in the ungauged areas.

Regional Characteristics Reflection Method in the Spatial Analysis Applying GIS - Case of Pyeongchang - (GIS를 활용한 공간분석에서 지역 특성의 반영 방법 - 평창을 사례로 -)

  • Kim, Chang-Hwan;Lee, Gi-Hwan;Jung, Young-Ho;Bae, Sun-Hak
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.3
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    • pp.93-106
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    • 2006
  • The purpose of this study was to find the method of spatial analysis using GIS that would best reflect the characteristics of study area. The purpose was successfully achieved. In order to carry out multicriteria decision analysis of the study results, the spatial analysis process reflecting the characteristics of study area was examined through stages of evaluation criteria standardization and evaluation indicator weighting decision. In the stage of evaluation criteria standardization, the characteristics of study area could be reflected through the adjustment of critical when converting a real value to a general value. In the stage of evaluation indicator weighting determination, the characteristics of the study area were reflected using the present condition of land use. The results of evaluating the grades of development-potential regions by reflecting characteristics of study area showed high correlativity between already developed region and new developing region. Such results show that, in spatial analysis, by combining expert questionnaire survey and literature survey, this method which reflects the characteristics of an area is very reasonable.

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A Study on Improvements of Eco-Natural Map Preparation Guideline through an Assessment of River - Focused on the Hwang River - (하천평가기준을 반영한 생태·자연도 작성지침 개선방안 연구 - 황강을 대상으로 -)

  • Kim, Dae-Young;Sung, Hyun-Chan
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.5
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    • pp.19-29
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    • 2012
  • The purpose of this study is to suggest improvements of Eco-Natural map preparation guideline by presenting assessment methods that can be applied to the result of river ecosystem health survey and assessment, using the Geographic Information System. The area for studying is the main stream of the Hwang River where is easy to collect data and available to compare before and after of river assessment. It was reevaluated by reflecting the result of river ecosystem health assessment of the Ministry of Environment. As the result, Eco-Natural map of the study area reflecting the river assessment, the changes in the area ratio by grade have been increased from 1.14% to 14.03% in the first-grade and from 24.64% to 43.91% in the second-grade. It is considered to present more realistic grade due to the assessment of the rivers that have not been reflected in the meantime. Consequently, the result of this study will be useful for establishing the development projects on the rivers, providing the foundation for more realistic and active protection.

Mobile MGIS Study for the Seomjin River Estuary (섬진강 하구역 Mobile MGIS 구축 연구)

  • PARK, Sang-Woo;KIM, Jung-Hyun;KIM, Jong-Kyu
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.1
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    • pp.172-179
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    • 2016
  • The study of Mobile MGIS (Marine Geographic Information System) based on the Android Mobile Platform is mainly performed on effective methodologies which transform real world data to computing world data. Mobile GUI system has its own target on reliable data service by acquisition of geometric information using EFDC (Environmental Fluid Dynamics Code) Model, accurate measurement and graphical visualization. Even simple visualizations can aid in the interpretation of complex hydrodynamic relationships that are frequently encountered in the marine environment. The Mobile MGIS provides an easy way for hydrodynamics geoscientists to construct complex visualizations that can be viewed with free software. This study proposes a Mobile GUI MGIS using EFDC Model result of Seomjin River estuary. Finally, we design a Seomjin River estuarine Coastal Waters Mobile MGIS integrating above data models. It must adds more ecological information and the various service item for approach more easily in order to user.

A Study on the Improvement of Management for Survey Control Points in Seoul City (서울시 측량 기준점 관리 개선방안에 관한 연구)

  • Lee, Woo Sik;Lee, Eun Young
    • Spatial Information Research
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    • v.20 no.5
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    • pp.111-118
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    • 2012
  • Survey control points managed by national and local governments are associated with civilian's property and they are very important national facilities. Despite the importance of surveying results, Database and mark of survey control points, there are many problems noticed of the management aspects such as manpower, systems, and related law. Currently, each local government has built and operated Geographic Information System(GIS) independently by National Geographic Information Systems(NGIS) results. but it is still difficult to have the integration, linking and utilizing. Therefore, In this study proposed the functional improvement of GIS based control points integrated system for providing information and management and the establishment of first-payment system due to the moving of control points. Through this studies will be able to solve the problem of recovery charges according to unknown contractor and establish the basis of manager and user-centric one-stop integration system.

GIS Software Quality Improvement Expense For a Testing Instance (시험사례를 통한 GIS 소프트웨어의 품질개선 비용)

  • Jo, Song-Jae;Kim, Sun-Bae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.1
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    • pp.474-485
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    • 2011
  • In this Study, the results of survey of evaluation cases on 10 GIS software were used as quality level index of GIS software in order to evaluate the quality of GIS (Geographic Information System) software. On the basis of such evaluation, analysis on the cost of improving the defectiveness accumulated of GIS software test cases was made. I am attempting to deduce the results that can be used assertively in promoting the justification for quality investment of enterprises or industrial units by quantitatively computing the cost essential in securing the quality by measuring the investment and effects on the quality through this.

Development of Soil Analysis System for Land Readjustment Using GIS (GIS를 이용한 경지정리 토양처리 분석시스템 개발)

  • Lee, Ju-Seung;Goh, Hong-Seok;Lee, So-Yeal
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.4 s.31
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    • pp.13-19
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    • 2004
  • It has been a common practice to use manually processed soil maps in planning of land readjustment. This study is intended to develop a geographic information system for computerized processing of soil maps. The pilot region of land readjustment for this study was set at a mountain area with diverse formation of soil. Cadastral maps were employed for the basis map, and the main map was prepared using the information obtained from in-situ soil survey and laboratory tests. The detailed soil maps were drawn using the geographic information system, and analyzed and compared with manually processed maps. The soil maps, in conjunction with a computer program of land readjustment design, can be applied in estimation of soil works appropriate for the given soil condition, and also in selecting the efficient construction equipments.

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Dissemination Policy of Digital Geographic Information to Improve User Accessibility (이용 활성화를 위한 지리정보 유통정책 연구)

  • Seol, Mun-Won
    • Journal of the Korean Society for Library and Information Science
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    • v.34 no.4
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    • pp.143-160
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    • 2000
  • The primary purpose of the present study is two-fold: i) to analyze the level of understanding and perception of stakeholders on the dissemination policy of digital geographic information and ii) to explore the policy direction to enhance the user accessibility based upon stakeholder analysis. The study is composed of descriptive analysis with extensive literature review and empirical analysis. The empirical analysis employs qualitative method as well as quantitative one, articulating perception of stakeholders in a comparative manner and suggesting policy directions. Based on the interview and the survey results, the study proposes the overall directions of dissemination policy to facilitate the efficient use of digital geographic information.

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