• Title/Summary/Keyword: River topographic maps

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A Study on Effective Flood Map Generation using NGIS Digital Topographic Maps (효율적인 홍수지도 구축을 위한 NGIS 수치지형도 활용에 관한 연구)

  • 송용철;권오준;김계현
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.04a
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    • pp.449-454
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    • 2004
  • Nowadays, flood hazard maps have been generated to minimize the loss of human lives due to flooding domestically. To generate the flood hazard maps, LiDAR data have mainly been used to provide topographic data. The LiDAR data requires, however, relatively higher cost and processing time. Therefore, the needs of validating possible use of topographic maps as an alternative source of LiDAR, which have been already existed from the NGIS project over the nation, has been raised. In this background, this study has generated a DEM over City of Kuri as a pilot study using conventional 1:1,000 and 1:5,000 topographic maps emphasizing the linkage of river profile with breakline processing algorithm to build the essential topographic data as accurate as possible. The results showed that the RMSE from topographic maps and LiDAR were 3.49 and 2.282 meter, respectively. Further study needs to be made to decide possible use of topographic maps instead of LiDAR including more easier updating of topographic maps to support flood map generation. In addition, 1:1,000 topographic mapping, which is limited to the urban areas so far, needs to be extended to the river areas.

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A Study on the Generation of DEM for Flood Inundation Simulation using NGIS Digital Topographic Maps (NGIS 수치지형도를 이용한 효율적인 홍수범람모의용 지형자료 구축에 관한 연구)

  • Kwon, Oh-Jun;Kim, Kye-Hyun
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.1 s.35
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    • pp.49-55
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    • 2006
  • Nowadays, flood hazard maps have been generated to minimize the damages from the flooding. To generate such flood hazard maps, LiDAR data can be used as data source with higher data accuracy. LiDAR data, however, requires relatively higher cost and longer processing time. In this background, this study proposed DEM generation using NGIS digital topographic maps. For that, breaklines were processed to count directions of water flows. In addition, the river profile data, unique data source to represent real topography of the river area, were integrated to the breaklines to generate DEM. City of Kuri in Kyunggi Province was selected for this study and 1:1,000 and 1:5,000 topographic maps were integrated to process breaklines and river profile data were also linked to generate DEM. The generated DEM showed relatively lower vertical accuracy from mixing 1:1,000 and 1:5,000 topographic maps since 1:1,000 topographic maps were not available for some portion of the area. However, the DEM generated demonstrated reasonable accuracy and resolution for flood map generation as well as higher cost saving effects. On the contrary, for more efficient utilization of NGIS topographic maps, periodic map updating needs to be made including technical consideration in building breaklines and applying interpolation methods.

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Flooding Area Estimation by Using Different River Topographic Maps (하천지형 구축 방법에 따른 홍수 시 예상 침수면적 산정)

  • Moon, Changgeon;Lee, Jungsik;Shin, Shachul;Son, Hogeun
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.9
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    • pp.21-28
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    • 2016
  • The purpose of this study is to compare the three areas that each estimated by using three different river topographic maps. For construction of river topographic maps, the data used in this study are ASTER, SRTM and a 1:5,000 scale digital map data sets in 14 streams of the Cheongdo-gun and Uiseong-gun. HEC-GeoRAS, RAS Mapper, and RiverCAD model are applied for the flooding area analysis using observed data and design rainfalls. The result of analysis is to compare observed flooding area based on the flood plain maps with estimated inundation area by hydraulic models and constructed river topographic maps. The results of this study are as follows; Flooding area by HEC-GeoRAS model is similar to the inundation area of flood plain map and appears in order of RAS Mapper, and RiverCAD model in all watersheds. Flood inundation area by SRTM DEM is similar to the result of 1:5,000 scale digital map in all watersheds and all analysis models. The SRTM DEM shows the most similarity to the digital map than ASTER DEM in all of the watershed scale and analysis models. HEC-GeoRAS and RiverCAD model are efficient models for flood inundation analysis in small watershed and HEC-GeoRAS and Ras Mapper model are efficient in medium to large watershed.

A study on stream morphological characteristics according to effect of Map Scale (지도축척의 영향에 따른 하천형태학적 특성연구)

  • 안상진;조용진
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.23 no.1
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    • pp.64-74
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    • 1981
  • The stream morphological characteristics of watershed have important influence upon the analysis of runoff. In this study, the effect of the map scale on the stream morphological characteristics was used on the data taken from 15'(1:50, 000) and 7'30"(1 :25,000) topographic maps which could cover the whole Miho River basin This basin are the first tributary of the Geum. River. Otherwise, the longitudinal stream bed profile was calculated by Yang's theoretical stream bed profile, equilibrium profile and actual profile. In the result of this investigation the conclusion is that the resultant relationship obtained from different topographic maps in the scale on the same stream system has come upon the same result as the stream morphological characteristics. Therefore, the great amount of time and effort can be saved in studing the stream morphological charecteristics by using the 15' instead of the 7'30"map system excluding the first order streams.

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Pliot Building of the Management System for River Thematic Maps (하천주제도 관리시스템 시범구축)

  • Park, Jin-Hyeog;Lee, Geun-Sang;Koh, Deuk-Koo;Kim, Kye-Hyun;Kim, Seong-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.8 no.2
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    • pp.95-102
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    • 2005
  • Currently, the government has been established GIS DB related to river as a part of the river map digitization projects such as RIMGIS and flood map. This study was aimed to demonstrate the generation of thematic maps related to river space and their management system, the one of the major river thematic maps proposed from the precedent study "Establishment of River Thematic Map Project" in an effort to maximize the utilization of river related database, the major product of the project for digitization of river maps. This study includes amending database model for building river thematic maps. Also, metadata were amended and built for efficient management and distribution of the river related data based on the national standard metadata proposed from "Establishing Standard Metadata" sponsored by National Geography Institute in 2003 for more effective management of river thematic maps. In addition, this study analyzed the method for utilizing existing data from RIMGIS and WAMIS as well as digital topographic maps to produce 25 river thematic maps in accordance of defined building procedure. Management system of the river thematic maps for Kyungan watershed has been generated for effective managing river thematic maps based on the design and pilot generation of river thematic maps, and metadata management function has been added into the management system.

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Development of flood hazard and risk maps in Bosnia and Herzegovina, key study of the Zujevina River

  • Emina, Hadzic;Giuseppe Tito, Aronica;Hata, Milisic;Suvada, Suvalija;Slobodanka, Kljucanin;Ammar, Saric;Suada, Sulejmanovic;Fehad, Mujic
    • Coupled systems mechanics
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    • v.11 no.6
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    • pp.505-524
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    • 2022
  • Floods represent extreme hydrological phenomena that affect populations, environment, social, political, and ecological systems. After the catastrophic floods that have hit Europe and the World in recent decades, the flood problem has become more current. At the EU level, a legal framework has been put in place with the entry into force of Directive 2007/60/EC on Flood Risk Assessment and Management (Flood Directive). Two years after the entry into force of the Floods Directive, Bosnia and Herzegovina (B&H), has adopted a Regulation on the types and content of water protection plans, which takes key steps and activities under the Floods Directive. The "Methodology for developing flood hazard and risk maps" (Methodology) was developed for the territory of Bosnia and Herzegovina, following the methodology used in the majority of EU member states, but with certain modifications to the country's characteristics. Accordingly, activities for the preparation of the Preliminary Flood Risk Assessment for each river basin district were completed in 2015 for the territory of Bosnia and Herzegovina. Activities on the production of hazard maps and flood risk maps are in progress. The results of probable climate change impact model forecasts should be included in the preparation of the Flood Risk Management Plans, which is the subsequent phase of implementing the Flood Directive. By the foregoing, the paper will give an example of the development of the hydrodynamic model of the Zujevina River, as well as the development of hazard and risk maps. Hazard and risk maps have been prepared for medium probability floods of 1/100 as well as for high probability floods of 1/20. The results of LiDAR (Light Detection and Ranging) recording were used to create a digital terrain model (DMR). It was noticed that there are big differences between the flood maps obtained by recording LiDAR techniques in relation to the previous flood maps obtained using georeferenced topographic maps. Particular attention is given to explaining the Methodology applied in Bosnia and Herzegovina.

Analysis of River Channel Morphology and Riparian Land Use Changes using Multi-temporal Aerial Photographs and Topographic Maps of the Early 20th Century in Gyeongan-cheon Watershed (시계열 항공사진과 20세기 초 지형도를 이용한 경안천유역의 하천형태 및 하천부지 변화추세 분석)

  • Park, Geun-Ae;Lee, Mi-Seon;Kim, Hyeon-Jun;Kim, Seong-Joon
    • Journal of Korea Water Resources Association
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    • v.38 no.5 s.154
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    • pp.379-390
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    • 2005
  • This study is to trace the change of stream shape using the past series of aortal photographs and topographic maps, and to compare the land use changes of inland along the stream. For the Gyeongan first & second class of local stream, aerial photographs of 1966, 1981 and 2000 were selected and ortho photographs were made with interior orientation and exterior orientation, respectively. In addition, topographic maps of 1914 - 1915 were used to compare with stream of 1966, 1981 and 2000. As apparent changes of the stream, the consolidated reaches of stream with levee construction were straightened and their stream width widened. Especially the stream width of inlet part of Paldang lake was widened almost twice because of the rise of water level by dam construction in 1974. The land use maps (1966, 1981, 2000) of riparian areas were also made, respectively and classified into 6 categories (water, forest, agricultural land, urban area, road, sandbar) by digitizing, The main changes of land use were agricultural land, urban area, road and sandbar.

Utilization of Thematic Mappers Data for the Comparison of Methods to Create Watersheds

  • Chang, Eun-Mi;Park, Kyeong;Kim, Young-Soo;Lee, Bok-Ho
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.343-348
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    • 1999
  • Delineation of watersheds is one of the most basic steps for water resource management and National Park management. The purpose of this study is to investigate how to utilize Thematic Mappers scenes to compare watersheds created by running a model with those produced by digitizing topographic maps of Keum River basin. A methodology is designed and tested using Geographic Information Systems (GIS) and remote sensing to map areas with various thematic maps. A CAD data on watersheds from the Decision Support system for Water Quality is converted into GIS format. The digital elevation model with 100-meter resolution is used to create watershed by cumulative watershed method. TM scenes are also classified by new procedures including stacking method, NDVI, NDWI, and unsupervised classification methods. To evaluate the relative correctness Kyerongsan National Park was studied intensively whose area was divided into 6 watersheds in both cases. The boundaries of watershed from the model are less correct than those of the topographic maps. This result shows that automated watershed creating system needs higher-resolution digital elevation model than 100-meters.

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Analysis of Stream Physiographic Characteristics of River Basin by using GIS (지리정보시스템을 이용한 하천유역의 지상학적 특성분석)

  • Ahn, Seung-Seop;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.3
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    • pp.23-34
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    • 1999
  • This study proposed the possibility of GIS to analyze stream physiographic characteristics of river basin which is important control factor in complex water management. Based on five 1:25,000 topographic maps which cover Yengchon Dam area locates upper area of Kumho River, this study analyzed the characteristics using Arc/Info(UNIX) GIS. Comparing its results and those from the existing method using digital planimeter, it could conclude as follows; First, as the results of the analysis of hypsometric curve of Yeungchon Dam area, it has the topographic characteristics of youth and maturity. And the landform of Yengchon Dam area has developed with regularity when Horton's three laws on the morphology of stream is applied. Second, the possibility of applying GIS to data management and utilization is sufficient even if it requires long time to construct topographic attribute data. Finally, a further research is needed on watershed direction with landform for the purpose of analyzing water source management and topographic property effectively.

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GIS based Water-pollutant Buffering Zone Management

  • Kim, Kye-Hyun;Yoon, Chun-Joo
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.506-506
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    • 2002
  • S. Korean Government has accelerating its efforts to enhance the quality of the drinking water. The Ministry of Environment has declared the law of securing water-pollutant buffering zone to minimize the inflow of the point and nonpoint sources into the drinking water sources. As a first phase of installing nationa-wide water-pollutant buffering zone, approximately 300km buffering zone has been delineated along the South and North Han river, the major drinking water sources for the capital area of S. Korea, which has the population of more than 12 millions. The buffering zone has the width of 1,000 meter for the special protection area, and 500 meter for the remaining area from both ends of the river. The major works have been done in three stages. Firstly, the boundaries lines of the buffering zone was delineated on the digital topographic maps. Secondly, the maps were overlayed with the cadastral maps to identify individual land parcels, the street address of the major pollutant discharging facilities, and all different types of pollutants including livestocks. Thirdly, the field work has been done as a verification. Once the buffering zone was generated, all the information for the buffering gone were created or imported from other government agencies including official land price, details of the major manufacturing facilities discharging considerable amount of pollutants, major motels and resorts, not to mention of restaurants, etc. Also, major livestock houses were located to identify the path of the pollutant inflow to the drinking water source. Further works need to be continued such as purchasing private lands within the buffering zone and change the land use in the efforts to decrease the pollutant amount and to provide more environmentally friendly space. Also, high resolution satellite imagery should be utilized in the near future as a cost-effective data source to update all the landuse activities within buffering zone.

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