• Title/Summary/Keyword: Topographical Data

Search Result 412, Processing Time 0.025 seconds

Web-based GIS for Real Time Hydrologic Topographical Data Extraction for the Geum River Watershed in Korea (Web기반 GIS를 이용한 금강유역의 실시간 수문지형인자 추출)

  • Nam, Won-Ho;Choi, Jin-Yong;Jang, Min-Won;Engel, B.A.
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.49 no.5
    • /
    • pp.81-90
    • /
    • 2007
  • Watershed topographical information is required in hydrologic analysis, supporting efficient hydrologic model operation and managing water resources. Watershed topographical data extraction systems based on desktop GIS are abundant these days placing burdens for spatial data processing on users. This paper describes development of a Web-based Geographic Information Systems that can delineate the Geum River sub-basins and extract watershed topographical data in real time. Through this system, users can obtain a watershed boundary by selecting outlet location and then extracting topographical data including watershed area, boundary length, average altitude, slope distribution about the elevation range with Web browsers. Moreover, the system provides watershed hydrological data including land use, soil types, soil drainage conditions, and NRCS(Natural Resources Conservation Service) curve number for hydrologic model operation through grid overlay technique. The system operability was evaluated with the hydrological data of WAMIS(Water Management Information System) with the government operation Web site as reference data.

Development of Web-GIS based SWAT Data Generation System (Web-GIS 기반 SWAT 자료 공급 시스템 구축)

  • Nam, Won-Ho;Choi, Jin-Yong;Hong, Eun-Mi;Kim, Hak-Kwan
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.51 no.6
    • /
    • pp.1-9
    • /
    • 2009
  • Watershed topographical data is essential for the management for water resources and watershed management in terms of hydrology analysis. Collecting watershed topographical and meteorological data is the first step for simulating hydrological models and calculating hydrological components. This study describes a specialized Web-based Geographic Information Systems, Soil Water Assessment Tool model data generation system, which was developed to support SWAT model operation using Web-GIS capability for map browsing, online watershed delineation and topographical and meteorological data extraction. This system tested its operability extracting watershed topographical and meteorological data in real time and the extracted spatial and weather data were seamlessly imported to ArcSWAT system demonstrating its usability. The Web-GIS would be useful to users who are willing to operate SWAT models for the various watershed management purposes in terms of spatial and weather preparing.

A Topographical Classifier Development Support System Cooperating with Data Mining Tool WEKA from Airborne LiDAR Data (항공 라이다 데이터로부터 데이터마이닝 도구 WEKA를 이용한 지형 분류기 제작 지원 시스템)

  • Lee, Sung-Gyu;Lee, Ho-Jun;Sung, Chul-Woong;Park, Chang-Hoo;Cho, Woo-Sug;Kim, Yoo-Sung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.28 no.1
    • /
    • pp.133-142
    • /
    • 2010
  • To monitor composition and change of the national land, intelligent topographical classifier which enables accurate classification of land-cover types from airborne LiDAR data is highly required. We developed a topographical classifier development support system cooperating with da1a mining tool WEKA to help users to construct accurate topographical classification systems. The topographical classifier development support system has the following functions; superposing LiDAR data upon corresponding aerial images, dividing LiDAR data into tiles for efficient processing, 3D visualization of partial LiDAR data, feature from tiles, automatic WEKA input generation, and automatic C++ program generation from the classification rule set. In addition, with dam mining tool WEKA, we can choose highly distinguishable features by attribute selection function and choose the best classification model as the result topographical classifier. Therefore, users can easily develop intelligent topographical classifier which is well fitted to the developing objectives by using the topographical classifier development support system.

A Dynamic Variable Window-based Topographical Classification Method Using Aerial LiDAR Data (항공 라이다 데이터를 이용한 동적 가변 윈도우 기반 지형 분류 기법)

  • Sung, Chul-Woong;Lee, Sung-Gyu;Park, Chang-Hoo;Lee, Ho-Jun;Kim, Yoo-Sung
    • Spatial Information Research
    • /
    • v.18 no.5
    • /
    • pp.13-26
    • /
    • 2010
  • In this paper, a dynamic variable window-based topographical classification method is proposed which has the changeable classification units depending on topographical properties. In the proposed scheme, to im prove the classification efficiency, the unit of topographical classification can be changeable dynamically according to the topographical properties and repeated patterns. Also, in this paper, the classification efficiency and accuracy of the proposed method are analyzed in order to find an optimal maximum decision window-size through the experiment. According to the experiment results, the proposed dynamic variable window-based topographical classification method maintains similar accuracy but remarkably reduce computing time than that of a fixed window-size based one, respectively.

Analysis of the Location Environment of the Sub-alpine Coniferous Forest in National Parks Using GIS - Focusing on Abies koreana - (GIS를 활용한 국립공원 아고산대 침엽수림의 입지환경 분석 - 구상나무를 대상으로 -)

  • Kim, Tae-Geun;Oh, Jang-Geun
    • Korean Journal of Ecology and Environment
    • /
    • v.49 no.3
    • /
    • pp.236-243
    • /
    • 2016
  • It was a case study to use as a basic data for efficient the preservation and management of subalpine coniferous forest in national parks. It is based on inhabitation condition of 210 individuals of Abies koreana Wilson that was found through local investigation in the sub-alpine zone of Jirisan National Park and Songnisan National Park. It analyzed the effect of the geographical location and topographical features, which are the basics of location environment, on the growth of A. koreana. The variables related to the growth of A. koreana are tree height and diameter at breast height. Topographical features include geographical longitude, altitude above sea level, slope of the mountains, aspect that describes the direction in which a slope faces and topographical wetness index. Topographical features were extracted through GIS spatial analysis. It used canonical correlation analysis to estimate whether the two variables groups have related to each other and how much they are related, if any, and estimated the effect of the geographical and topographical features on the growth structure of A. koreana using multiple regression analysis. The tree height and diameter at breast height that represent the growth structure of A. koreana show greater relation to geographical latitude distribution than topographical feature and the geographical and topographical factors show greater relation to diameter at breast height than tree height. The growth structure's variable and geographical and topographical variable of A. koreana have meaningful relation and the result shows that geographical and topographical variables explain 18.1% of the growth structure. The variables that affect the diameter at breast height of A. koreana are geographical latitude, topographical wetness index, aspect and altitude, which are put in order of statistical significance. The higher the latitude is, the smaller the diameter at breast height. Depending on the topographical feature, it becomes bigger. The variable that affects the tree height is topographical wetness index, which was the only meaningful variable. Overall, the tree height and diameter at breast height that are related to the growth structure of A. koreana are affected by geographical and topographical feature. It showed that the geographical feature affected it the most. Especially the effect of water among the topographical features is expected to be bigger than the other topographical factors. Based on the result, it is expected that geographical and topographical feature is an important factor for the growth structure of A. koreana. Even though it considered only the geographical and topographical features and used spatial analysis data produced by GIS, the research results will be useful for investigating and researching the growth environment of coniferous forest inhabiting in sub-alpine zone of national parks and are expected to be used as basic data for establishing measures to efficiently manage and preserve evergreen needleaf tree such as A. koreana.

Topographical Change Detection for Digital Map Update (수치지도 수시갱신을 위한 지형변화 탐지)

  • Park, Yong-Cheol;Lee, Im-Pyeong;Yoo, Chang-Ho;Yun, Ha-Soo
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2007.04a
    • /
    • pp.289-293
    • /
    • 2007
  • Because the current numerical value map and update system in use do not reflect rapidly enough the transformation of topography, their usage are gradually in decrease. Therefore, there is an increasing demand for reception update system of numerical value map which can guarantee the accuracy and up-to-dateness of data. While rapid detection of topographical transformation is essential for rapid updating, the existing research based on remote investigation or direct measurement was difficult to apply efficiently in terms of cost and accuracy. Thereupon, this research aims to present efficient methods of detecting topographical transformations for a frequent real time updating of numerical value map using the topographical transformation and related data inputted in real time into the administrative information system.

  • PDF

Effect of watershed characteristics on the criteria of Flash Flood warning (유역인자의 특성이 경계경보발령 기준에 미치는 영향분석)

  • 양인태;김재철;김태환
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2004.11a
    • /
    • pp.389-392
    • /
    • 2004
  • A recent unusual change in the weather is formed as a localized heavy rain in a short time. This phenomenon has caused a flash flood, and flash floods extensively have damaged human lives many times. In large river's case, the extent of loss of lives and properties has been decreased through the flood warning system by flood control stations of each stream. However, the extent of damage in other small rivers has increased reversely. Therefore, it is necessary to establish a new flood warning system against flash floods instead of the existing flood warning system. It is a specific character that the damage from flash floods in mountain streams brings much more loss of lives than large river's flood. The purpose of this study is calculating the characteristic of flash floods in streams, analyzing topographical characteristics of water basin through applying GIS techniques with the calculation as mentioned above and researching what topographical conditions have influence on hydrological flash floods in water basin. The flash flood prediction model we used is made by GIUH (geomorphoclimatic instantaneous unit hydrograph) with hydrologic-topographical technology. As applying the flash flood prediction model, this is a procedure for calculating topographical information in basin: we made a topological data up out of database with utilizing GIS, and we also produced a DEM (digital elevation model) and used it as a topographical data for determining amount of flash floods.

  • PDF

An Experimental Study on the Construction of Administrative Boundaries Using Old Topographical Map in the 1910s (1910년대 고 지형도를 이용한 행정리 경계 구축에 관한 실험적 연구)

  • Eom, Seong-Jun;Cho, Suk-Yeong;You, Soo-Jin;An, Phil-Gyun
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.23 no.2
    • /
    • pp.45-54
    • /
    • 2021
  • This study aims to establish administrative boundaries by utilizing digitalized old topographical map. Various problems have arisen due to unclear administrative boundaries. For example, there are various problems such as conflict amongst residents to occupy a larger area, unnecessary waste of administrative power, and difficulty in collecting various data for administrative units (farm area, statistical data, spatial analysis, living ara analysis). Therefore, in this study, an experimental study was conducted to establish administrative boundaries by using an old topographical map containing information on villages before administrative reform in 1914. As a result, the boundaries of towns, towns and villages were largely consistent. In order to divide the administrative boundaries based on the legal district boundaries, the administrative boundaries were established by referring to the contents of village introduction and natural boundaries (roads, rivers, mountain ranges, etc.) provided in towns and villages. However, there was a limit in establishing a precise boundary as it was not possible to secure a high-quality digitalized old topographical map.

A FORECASTING METHOD FOR FOREST FIRES BASED ON THE TOPOGRAPHICAL CLASSIFICATION SYSTEM AND SPREADING SPEED OF FIRE

  • Koizumi, Toshio
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 1997.11a
    • /
    • pp.311-318
    • /
    • 1997
  • On April 27,1993, a forest fire occurred in Morito-area, Manba-city, Gunma-prefecture Japan. Under the prevailing strong winds, the fire spread and extended to the largest scale ever in Gunma-prefecture. The author chartered a helicopter on May 5, one week after the fire was extinguished, and took aerial photos of tile damaged area, and investigated the condition. of the fire through field survey and data collection. The burnt area extended. over about 100 hectares, and the damage amounted to about 190 million yen (about two million dollar). The fire occurred at a steep mountainous area and under strong winds, therefore, md and topography strongly facilitated the spreading, It is the purpose of this paper to report a damage investigation of the fire and to develop the forecasting method of forest fires based on the topographical analysis and spreading speed of fire. In the first place, I analyze the topographical structure of the regions which became the bject of this study with some topographical factors, and construct a land form classification ap. Secondly, I decide the dangerous condition of each region in the land form classification map according to the direction of the wind and spreading speed of f'kre. In the present paper, I try to forecast forest fires in Morito area, and the basic results for the forecasting method of forest fires were obtained with the topographical classification system and spreading speed of fire.

  • PDF