• Title/Summary/Keyword: Geographic Data

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Development of an Automatic Generation Methodology for Digital Elevation Models using a Two-Dimensional Digital Map (수치지형도를 이용한 DEM 자동 생성 기법의 개발)

  • Park, Chan-Soo;Lee, Seong-Kyu;Suh, Yong-Cheol
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.3
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    • pp.113-122
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    • 2007
  • The rapid growth of aerial survey and remote sensing technology has enabled the rapid acquisition of very large amounts of geographic data, which should be analyzed using real-time visualization technology. The level of detail(LOD) algorithm is one of the most important elements for realizing real-time visualization. We chose the triangulated irregular network (TIN) method to generate normalized digital elevation model(DEM) data. First, we generated TIN data using contour lines obtained from a two-dimensional(2D) digital map and created a 2D grid array fitting the size of the area. Then, we generated normalized DEM data by calculating the intersection points between the TIN data and the points on the 2D grid array. We used constrained Delaunay triangulation(CDT) and ray-triangle intersection algorithms to calculate the intersection points between the TIN data and the points on the 2D grid array in each step. In addition, we simulated a three-dimensional(3D) terrain model based on normalized DEM data with real-time visualization using a Microsoft Visual C++ 6.0 program in the DirectX API library and a quad-tree LOD algorithm.

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A Design of GML document editing system based on XML (XML 기반의 GML 문서 저작 시스템 설계)

  • Hao, Ri-Ming;Bang, Jin-Suk;Cao, Ke-Lang;Choi, Bong-Kyu;Yu, Lei;Jung, Hoe-Kyung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.531-534
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    • 2008
  • Recently, by the interest of geographical information and the utilization field of geographical information diversifying. Various GIS(Geographic Information System) was built to manage geographical information efficiently. However, because of interoperability between geographic information system, OGC(Open Geospatial Consortium) standardized GML(Geography Markup Language) of the XML(eXtensible Markup Language) foundation in which an interoperability writes possible geographical information data. GML national standard is applied to various application fields at present, and the use is confirmed. In this paper, GML 3.2.1 encoding standard specification follows requirements of OGC recommendation, we designed GML document editing system using XML standard technology, and generated interoperability GML data.

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Flow Estimation Using Rainfalls Derived from Multiple Satellite Images in North Korea (위성 강우자료를 이용한 북한지역 홍수량 추정)

  • KIM, Joo-Hun;CHOI, Yun-Seok;KIM, Kyung-Tak
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.4
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    • pp.31-42
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    • 2015
  • The objective of this study is to estimate the flood flow of inaccessible regions using satellite-derived rainfall and global geographic data. This study focuses on Dongsingun, an area located upstream of the Cheongcheon River in North Korea. The IFAS model was used to estimate flood flow. The model was calibrated in the Gap Stream watershed in South Korea and verified for the Byeongsung Stream watershed in the Nakdong River basin. Satellite-derived rainfalls for North Korea was revised using ground gauge data. Analysis results using CMORPH and GSMaP_NRT showed $4,886m^3/s$ and $5,718m^3/s$ respectively. In future studies, hydrological analysis in unmeasured and inaccessible regions will be carried out by applying more rainfall events.

Analysis of Spatial Crime Pattern and Place Occurrence Characteristics for Building a Safe City (안전도시 조성을 위한 범죄의 공간적 분포와 도시의 장소별 발생특성 분석)

  • Heo, Sun-Young;Moon, Tae-Heon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.4
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    • pp.78-89
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    • 2012
  • The purpose of this study is to examine the possibility of crime prevention in consideration of urban physical environment by analyzing the spatial distribution characteristics and pattern using actual crime occurrence data of the case city. The crime data was rebuilt by transforming them into geographic information system to analyze the spatial aspect of crime occurrence. The findings are as follows: a change from 2008 to 2011 is indicated with similar trend. But the local movements of crime hot spots are found. Moreover crimes were happening along the roads in linear pattern rather than inside of blocks in commercial area. This indicates the importance of environmental improvement of roads and open spaces. In addition it was found that the crime occurrence in a dangerous district can be reduced and prevented through the physical environment design and urban planning. The findings will contribute to promoting fundamental crime prevention as the physical environmental improvement in a city and to building a safe community as its result.

Analysis of Flooded Areas for Cadastral Information-Based Rainfall Frequencies (지적정보 기반의 강우빈도별 침수지역 분석)

  • Min, Kwan-Sik;Lee, Hyung-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.4
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    • pp.101-110
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    • 2010
  • The increased occurrence of flooding due to typhoons and local rainfall has necessitated damage prevention through the systematic construction of damage history and quantitative analysis of flood prediction data. In this study, we constructed a disaster information map for practical use by combining digital images and continuous cadastral maps of damaged areas using a geographic information system to provide basic data and attribute information. In addition, we predicted the areas at risk of flash floods by calculating the flood capacity of the study area for different rainfall frequencies through flood inundation simulation, which was used to obtain comprehensive disaster information. Further, we calculated the extent of the flooded area and the damage rate for different rainfall frequencies using cadastral information. Flood inundation simulation in the case of heavy rainfall was found to help improve the ability to react to a flood and enhance the efficiency of rescue work by supporting decision-making for disaster management.

A Study on Temporal Map for Spatio-temporal Analysis (시.공간분석을 위한 GIS기법의 시간 지도 구현에 관한 연구 - 안양시틀 사례로 -)

  • 오충원
    • Journal of the Korean Geographical Society
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    • v.37 no.2
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    • pp.191-202
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    • 2002
  • Characteristics and patterns of geographic features and human activities can be interpreted in terms of spatiality and temporality. The necessity to record the historical changes and the ability to reason in the real world has lead to a new field of research so called Integrated Spatio-Temporal analysis. The objective of this study is to investigate temporal maps for Spatio-temporal analysis, which have the integration functionality for visualizing spatiality and temporality of the geographic appearances and human activities. Land information is composed of spatial, attribute and temporal data and requires spatio-temporal representations. It is possible to visualize spatio-temporal variations with spatio-temporal databases and temporal map produced by integrated data models. This study constructs spatio-temporal model for temporal maps of land price variation analysis. Taking advantage of the spatio-temporal model proposed here, it is possible to visualize spatio-temporal variations with spatio-temporal database and temporal map. On a practical level, this study would be extended and utilized to various geographic features.

A Study on the Spatial Distribution Characteristic of Urban Surface Temperature using Remotely Sensed Data and GIS (원격탐사자료와 GIS를 활용한 도시 표면온도의 공간적 분포특성에 관한 연구)

  • Jo, Myung-Hee;Lee, Kwang-Jae;Kim, Woon-Soo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.4 no.1
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    • pp.57-66
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    • 2001
  • This study used four theoretical models, such as two-point linear model, linear regression model, quadratic regression model and cubic regression model which are presented from The Ministry of Science and Technology, for extraction of urban surface temperature from Landsat TM band 6 image. Through correlation and regression analysis between result of four models and AWS(automatic weather station) observation data, this study could verify spatial distribution characteristic of urban surface temperature using GIS spatial analysis method. The result of analysis for surface temperature by landcover showed that the urban and the barren land belonged to the highest surface temperature class. And there was also -0.85 correlation in the result of correlation analysis between surface temperature and NDVI. In this result, the meteorological environmental characteristics wuld be regarded as one of the important factor in urban planning.

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A Study on the application of GML for the expansion of services of the National Geographic Information Clearinghouse (지리정보유통서비스 확장을 위한 GML 적용방안 연구)

  • Hong, Sang-Gi;Yun, Seok-Beom
    • 한국공간정보시스템학회:학술대회논문집
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    • 2004.12a
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    • pp.182-194
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    • 2004
  • There has been significant progress in the method of digital information sharing in recent years. To take advantage of the benefits of XML, OGC developed GML, which is the application of XML in the field of GIS, and released web service Implementation specification for offering GML services. Through the use of GML, therefore, it is possible to expand the methods of sharing geographical information through the Web. This study aims to develop a method to apply GML to improve the geographic information sharing services. GML can be used to effectively offer data in real time so that the currentness of the data can be maintained. This study analysed the architecture of the National Geographic Information Clearinghouse and developed a GML specification and web services that can be used within the existing architecture to expand the services. Based on the specification, this study constructed a prototype system to proved the concept.

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Development of Location based Augmented Reality System for Public Underground Facility Management (공공지하시설물 관리를 위한 증강현실 시스템 개발)

  • Lee, Hyo-Jin;Kim, Ji-Sung;Seo, Ho-Seok;Cho, Young-Sik
    • Journal of Digital Contents Society
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    • v.19 no.2
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    • pp.237-243
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    • 2018
  • Most of public underground facilities are installed under the ground, thus it is difficult to recognize the accurate location even with the drawings. Studies are conducted to understand exact position of underground facilities using augmented reality. However, in those studies, establishing of additional 3D object model database is needed when AR system is used at field. Because most of public underground facility information are established as 2 dimensional. In this study, AR system is developed as mobile application which can use original 2D underground facility data to transfer 3D AR data automatically without additional 3D database establishment.

Lessons from the Application of GIS for Local Government - Some Examples from Korea and Australia - (지방자치단체에서의 GIS 활용에 대한 제언 - 한국과 호주에서의 사례연구를 중심으로 -)

  • Peterson, Jim;Kim, Chang Hwan;Yoo, Jae Yong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.3
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    • pp.107-117
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    • 2002
  • Public policy responses to the digital/information revolution and the micro-economic reforms that it facilitates have inspired exploration of the scope for local government implementation of digital spatial data handling(DSDH) of information relating to, among other things, asset inventory, environmental and utility management, address management, and planning. The results from these explorations are such that few doubt the value of bringing the public policies to practice, but diffusion rate and pattern of the approaches demonstrated by the scoping experiments will reflect institutional/cultural matters, indicators of the relative significance of which might be at least partly predicted from appraisal of case studies. This argument is exemplified by reference to case studies in adoption of DSDH by local government organizations in Korea and in Australia.

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