• Title/Summary/Keyword: National Geographic Information Systems

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Study about the Applicable Plan of GIS on Range of Magnetic Field Emitted from 60 Hz Powerline (60Hz 고압 송전선로의 자기장 발생범위에 대한 GIS 적용 방안에 대한 연구)

  • Hong, Seung Cheol;Choi, Seong Ho;Kim, Yoon Shin;Park, Jae Young
    • Journal of Environmental Impact Assessment
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    • v.15 no.4
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    • pp.271-277
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    • 2006
  • In this study, we investigated the applicable plan of GIS on the environmental impact assessment of 60 Hz Powerline. So we assessed distance data based on calculations by use of 2D and 3D Geographical information systems(GIS) and distance data based on measurements on 1: 5000 maps accord with on site distance measurements to use input data for calculating magnetic field. One hundred eight of the on site measured addresses were selected from residences. The data were achieved by measuring the distance between residence and power line on maps with scales of 1: 5000. The digital map was obtained from National Geographic Information Institute with scales of 1: 5000, and we made 2D and 3D map. Correlation analyses were performed for statistical analyses. For the 3D GIS versus on site comparison of different exposure categories, 70 of 108 measurements were assigned to the correct category. Similarly for 2D GIS versus on site comparison, 71 of 108 were correctly categorized. When comparing map measurement with on site measurement, 62 of 108 were correctly categorized. When the correlation analysis was performed, best correlation was found between 3D GIS and on site measurements with r = 0.84947 (p<0.0001). The correlation between map and on site measurement yielded an r of 0.76517 (p<0.0001). Since the GIS measurements and map measurement were made from the center point in the building and the on site measurements had to be made from the closest wall on the building, this might introduce and additional error in urban areas. The difference between 2D and 3D calculations were resulted from the height of buildings.

Topological Boundary Detection in Wireless Sensor Networks

  • Dinh, Thanh Le
    • Journal of Information Processing Systems
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    • v.5 no.3
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    • pp.145-150
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    • 2009
  • The awareness of boundaries in wireless sensor networks has many benefits. The identification of boundaries is especially challenging since typical wireless sensor networks consist of low-capability nodes that are unaware of their geographic location. In this paper, we propose a simple, efficient algorithm to detect nodes that are near the boundary of the sensor field as well as near the boundaries of holes. Our algorithm relies purely on the connectivity information of the underlying communication graph and does not require any information on the location of nodes. We introduce the 2-neighbor graph concept, and then make use of it to identify nodes near boundaries. The results of our experiment show that our algorithm carries out the task of topological boundary detection correctly and efficiently.

Design and Implementation of Components to Represent the 3-Dimensional+Temporal Objects (3차원+Temporal 객체를 표현하기 위한 컴포넌트 설계 및 구현)

  • Lee, Hyun Ah;Kim, Jin Suk;Ryu, Keun Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.7 no.4
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    • pp.119-132
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    • 2004
  • As geographic object is consisted of 3-dimensional, it must be appropriated use the 3-dimensional coordinate system to express for exact representation. To define 3-dimensional+temporal object model we extended 3-dimensional space and valid time from object model of OpenGIS consortium that is limited to 2-dimensional space. This methodology guarantees compatibility with other systems to construct with the open model. Also, it permitted administration for two kinds of object by considering both objects whose position and shape changes discretely over time and objects whose position changes continuously. 3-dimensional+temporal object model was implemented by 3-dimensional+temporal object component using OLE/COM techniques. The interfaces of the component defined based on 3-dimensional+temporal object model. To use this component, we implement the data consumer for 3-dimensional+temporal data.

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Modeling of Roads for Vehicle Simulator Using GIS Map Data

  • Im Hyung-Eun;Sung Won-Suk;Hwang Won-Gul;Ichiro Kageyama
    • International Journal of Precision Engineering and Manufacturing
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    • v.6 no.4
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    • pp.3-7
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    • 2005
  • Recently, vehicle simulators are widely used to evaluate driver s responses and driver assistance systems. It needs much effort to construct the virtual driving environment for a vehicle simulator. In this study, it is described how to make effectively the roads and the driving environment for a vehicle simulator. GIS (Geographic Information System) is used to construct the roads and the environment effectively. Because the GIS is the integrated system of geographical data, it contains useful data to make virtual driving environment. First, boundaries and centerlines of roads are extracted from the GIS. From boundaries, the road width is calculated. Using centerlines, mesh models of roads are constructed. The final graphic model of roads is constructed by mapping road images to those mesh models considering the number of lanes and the kind of surface. Data of buildings from the GIS are extracted. Each shape and height of building is determined considering the kind of building to construct the final graphic model of buildings. Then, the graphic model of roadside trees is constructed to decide their locations. Finally, the driving environment for driving simulator is constructed by converting the three graphic models with the graphic format of Direct-X and by joining the three graphic models.

A Study on Building the HD Map Prototype Based on Web GIS for the Generation of the Precise Road Maps (정밀도로지도 제작을 위한 Web GIS 기반 HD Map 프로토타입 구축 연구)

  • KWON, Yong-Ha;CHOUNG, Yun-Jae;CHO, Hyun-Ji;GU, Bon-Yup
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.2
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    • pp.102-116
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    • 2021
  • For the safe operation of autonomous vehicles, the representative technology of the 4th industrial revolution era, a combination of various technologies such as sensor technology, software technology and car technology is required. An autonomous vehicle is a vehicle that recognizes current location and situation by using the various sensors, and makes its own decisions without depending on the driver. Perfect recognition technology is required for fully autonomous driving. Since the precise road maps provide various road information including lanes, stop lines, traffic lights and crosswalks, it is possible to minimize the cognitive errors that occur in autonomous vehicles by using the precise road maps with location information of the road facilities. In this study, the definition, necessity and technical trends of the precise road map have been analyzed, and the HD(High Definition) map prototype based on the web GIS has been built in the autonomous driving-specialized areas of Daegu Metropolitan City(Suseong Medical District, about 24km), the Happy City of Sejong Special Self-Governing City(about 33km), and the FMTC(Future Mobility Technical Center) PG(Proving Ground) of Seoul National University Siheung Campus using the MMS(Mobile Mapping System) surveying results given by the National Geographic Information Institute. In future research, the built-in precise road map service will be installed in the autonomous vehicles and control systems to verify the real-time locations and its location correction algorithm.

Analysis of Inundation Area in the Agricultural Land under Climate Change through Coupled Modeling for Upstream and Downstream (상·하류 연계 모의를 통한 기후변화에 따른 농경지 침수면적 변화 분석)

  • Park, Seongjae;Kwak, Jihye;Kim, Jihye;Kim, Seokhyeon;Lee, Hyunji;Kim, Sinae;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.66 no.1
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    • pp.49-66
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    • 2024
  • Extreme rainfall will become intense due to climate change, increasing inundation risk to agricultural land. Hydrological and hydraulic simulations for the entire watershed were conducted to analyze the impact of climate change. Rainfall data was collected based on past weather observation and SSP (Shared Socio-economic Pathway)5-8.5 climate change scenarios. Simulation for flood volume, reservoir operation, river level, and inundation of agricultural land was conducted through K-HAS (KRC Hydraulics & Hydrology Analysis System) and HEC-RAS (Hydrologic Engineering Center - River Analysis System). Various scenarios were selected, encompassing different periods of rainfall data, including the observed period (1973-2022), near-term future (2021-2050), mid-term future (2051-2080), and long-term future (2081-2100), in addition to probabilistic precipitation events with return periods of 20 years and 100 years. The inundation area of the Aho-Buin district was visualized through GIS (Geographic Information System) based on the results of the flooding analysis. The probabilistic precipitation of climate change scenarios was calculated higher than that of past observations, which affected the increase in reservoir inflow, river level, inundation time, and inundation area. The inundation area and inundation time were higher in the 100-year frequency. Inundation risk was high in the order of long-term future, near-term future, mid-term future, and observed period. It was also shown that the Aho and Buin districts were vulnerable to inundation. These results are expected to be used as fundamental data for assessing the risk of flooding for agricultural land and downstream watersheds under climate change, guiding drainage improvement projects, and making flood risk maps.

Local Surface Ground Temperature based on Energy Balance Model with the use of GRID/GIS, Remote Sensed and Meteorological Station Data

  • Ha, Kyung-Ja;Shin, Sun-Hee;Oh, Hyun-Mi;Kim, Jae-Hwan
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.63-65
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    • 2003
  • The purpose of the study is to produce the surface ground temperature diagnostically using surface EBM with the use of GRID model in Geographic Information Systems (GIS). Certain characteristics have been analyzed for local slope effect, coastal effect and influence of high orographic aspect on the surface ground temperature. We present discussions on the meteorological responsibility for their temperature. The derived surface ground temperatures can be provided for comparison with those from satellite-based observ ation.

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Development of Walkability Search System (보행친화도 검색 시스템 개발)

  • Kim, Eun Jung;An, Donghyeok
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.9 no.12
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    • pp.987-997
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    • 2019
  • Walk score, walkablity index of built environmental condition, has developed and used in everyday life in United States. The purpose of this study is to produce walk score in Seoul, and to develop computer-based walk score system for improving it's usage. This study covers city of Seoul, and the unit of spatial analysis is 100m × 100m grid cell. This study uses same methodology with walk score in US, the Geographic Information Systems(GIS) is used for calculating the values of walk score(N=58,062). This study implemented Java-based system that utilizes walk score dataset(latitude, longitude, and walk score). This system provided search functions including both lat/long-based and address-based options. Meanwhile, this system was designed to provide the closest value of walk score in dataset if location did not match the certain points in dataset. This study has significance to provide walk score system being easily available to all.

Construction and Application of a Web-EOC Based Real-Time Monitoring Management System in Steep Slopes (Web-EOC 기반 경사지 실시간 계측관리시스템 구축 및 적용)

  • LEE, Jin-Duk;CHANG, Ki-Tae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.2
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    • pp.107-119
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    • 2018
  • The slope monitoring systems which have been operating at home and abroad were investigated and then the real-time monitoring management system for evacuating inhabitants based on Web-EOC(Emergency Operating Center) was constructed. We tried to analyze realistically and precisely the situation by changing from the existing field-centered management to sensor-centered management that measures coordinates and provides in real-time data of measuring/monitoring sensors installed at a field site and developing related viewer programs. In addition, the 3D based monitoring management system, which has alarm functions in case of emergency and provides information about the evacuation place, was constructed on the base that is able to expand to nationwide fields by using Vworld 3D map. Ten steep slope monitoring sites were registered on Web-EOC slope monitoring management system constructed in the research and then application instances were suggested.

Developing a Hybrid Web-based GIS for Improving Access to Distributed Spatial Data and Spatial Modeling Tools (분산형 공간모델링을 구현하기 위한 하이브리드형 웹기반 GIS의 개발)

  • Jun, Byong-Woon;Park, Chan-Suk;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.3 no.2
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    • pp.61-72
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    • 2000
  • The maturation of the Web technology has reshaped the ways in which data are accessed, disseminated, and shared. Thanks to its popularity along with the advance of spatial information technology, four major changes have been further made in traditional geographic information systems (GIS) in relation to access to data, distribution of data, access to GIS functionality, and visualization of multimedia data. Although access to and dissemination of spatial data over the Web has in recent years been addressed in the literature, little research effort has addressed the issue of access to and processing of GIS analysis functions over the Web. This research explores the potential use of Web-based GIS in improving accessibility to distributed spatial data and spatial modeling tools. A prototype Web-based GIS developed in this study focuses on Web-based location-allocation modeling for spatial decision support, and employs a hybrid approach that uses the Arc/Info software as a GIS server and CGM viewer as a client-side plug-in. This research shows that Web-based GIS is a useful vehicle in conducting spatial modeling in the particular user community. In addition, this study represents the possibility of Web-based GIS in developing open spatial decision supporting systems.

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