• Title/Summary/Keyword: Topographic Analysis

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THE EFFECTS OF UNCERTAIN TOPOGRAPHIC DATA ON SPATIAL PREDICTION OF LANDSLIDE HAZARD

  • Park, No-Wook;Kyriakidis, Phaedon C.
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.259-261
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    • 2008
  • GIS-based spatial data integration tasks have used exhaustive thematic maps generated from sparsely sampled data or satellite-based exhaustive data. Due to a simplification of reality and error in mapping procedures, such spatial data are usually imperfect and of different accuracy. The objective of this study is to carry out a sensitivity analysis in connection with input topographic data for landslide hazard mapping. Two different types of elevation estimates, elevation spot heights and a DEM from ASTER stereo images are considered. The geostatistical framework of kriging is applied for generating more reliable elevation estimates from both sparse elevation spot heights and exhaustive ASTER-based elevation values. The effects of different accuracy arising from different terrain-related maps on the prediction performance of landslide hazard are illustrated from a case study of Boeun, Korea.

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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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Relationship between Forest Stands Characteristics and NASA/JPL AIRSAR Polarimetric Data Over Mountainous Terrain

  • Kim, Du-Ra;Lee, Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.435-440
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    • 2002
  • The objective of this study is to analyze the relationship between polarimetric radar backscatters and stand characteristics over the mountainous forest area. L- and P-band full polarimetric airborne SAR data obtained in September 2000 were processed to compare with forest stand maps and ground collected stand variables. After the geometric registration of SAR image, mean radar backscatters were extracted for those ground plots where the stand parameters, such as tree height, DBH, and basal area, were measured during and after the SAR data acquisition. Preliminary analysis was focused on the topographic influence of radar backscattering under the homogeneous forest stand condition. Topographic effects, assessed by the local incidence angles, were different obvious in L-band data while it was not clear with P-band data.

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A Study on Landscape Management Techniques of Cultural Heritage Designated Area Using 3D Mapping Method (3D맵핑을 이용한 문화재 지정구역 경관관리기법 연구)

  • Kim, Jae-Ung;Lee, Won-Ho;Shin, Hyun-Sil
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.97-108
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    • 2018
  • The purpose of this study is to propose the construction of a visibility analysis model, which is the basis of the analysis for landscape management on the heritage sites such as historic villages and scenic sites. Results of the visibility analysis using DEM and the visibility analysis of DSM based on 3D mapping data are compared as follows: Precision level of the extracted data was confirmed to be less than 6.5cm, based on RTK survey results produced by constructing orthoimage data and DSM from the digital data of 2cm-class GSD(Ground Sample Distance) obtained by using a small UAV(Unmanned Aerial Vehicle). As a result of comparing the visibility analysis data of Digital Surface Model (DSM) using a small UAV with Digital Elevation Model(DEM) applying the height of the building to the Digital Topographic Map, it was confirmed that more realistic visibility analysis can be accomplished by applying DSM, as the structures such as fences, trees, and houses are reflected in the topographic data. The visibility analysis model using the 3D mapping technique can efficiently obtain the constantly changing topographic information when needed, by immediately constructing the data by utilizing a small UAV. It seems to be possible to propose a reasonable analysis result for preservation management such as landscape evaluation of cultural property.

Rational Unification Scheme of Topographic Surveying and Cadastral Survey for the Synergistic Convergence Effect of GIS Industry (공간정보산업의 상승적 융합 효과 창출을 위한 측량과 지적의 합리적 통합방안)

  • Park, Hong Gi;Joo, Yong Jin;Min, Kwan Sik;Kim, Young Dan
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.1
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    • pp.69-78
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    • 2013
  • Recently, as GIS industry has substantially grown up, convergence between industries such as the application coverage of surveying and cadastral information is gradually on the increase. The new approach of convergence between topographic surveying and cadastral survey is indispensable to make the change of geospatial environment ready and to maximize the utilization of National Spatial Data Infrastructure(NSDI). The purpose of this paper is to seek the way of synergistic improvement in topographic surveying and cadastral survey in comprehensive aspects of national geospatial information. First, we reviewed policy environment to clearly establish aim of convergence and promising perspective of GIS industry policy, considering NSDI. In addition, we examined current state of administration (organization, human resource, service) and institution situation. We came up with interior ability and external policy environment as well as critical success factor for the synergistic convergence by using SWOT analysis. Lastly, we developed basic perspective of convergence and improvement model and concrete scheme for stakeholder to complementary make progress. We can come to conclusion that the convergence of topographic surveying and cadastral survey should be not only carried in macro outline of successful NSDI but also committed to completion and maintenance of GIS framework.

The Selection Methodology of Road Network Data for Generalization of Digital Topographic Map (수치지형도 일반화를 위한 도로 네트워크 데이터의 선택 기법 연구)

  • Park, Woo Jin;Lee, Young Min;Yu, Ki Yun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.31 no.3
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    • pp.229-238
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    • 2013
  • Development of methodologies to generate the small scale map from the large scale map using map generalization has huge importance in management of the digital topographic map, such as producing and updating maps. In this study, the selection methodology of map generalization for the road network data in digital topographic map is investigated and evaluated. The existing maps with 1:5,000 and 1:25,000 scales are compared and the criteria for selection of the road network data, which are the number of objects and the relative importance of road network, are analyzed by using the T$\ddot{o}$pfer's radical law and Logit model. The selection model derived from the analysis result is applied to the test data, and the road network data of 1:18,000 and 1:72,000 scales from the digital topographic map of 1:5,000 scale are generated. The generalized results showed that the road objects with relatively high importance are selected appropriately according to the target scale levels after the qualitative and quantitative evaluations.

Evaluation of Grid-Based ROI Extraction Method Using a Seamless Digital Map (연속수치지형도를 활용한 격자기준 관심 지역 추출기법의 평가)

  • Jeong, Jong-Chul
    • Journal of Cadastre & Land InformatiX
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    • v.49 no.1
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    • pp.103-112
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    • 2019
  • Extraction of region of interest for satellite image classification is one of the important techniques for efficient management of the national land space. However, recent studies on satellite image classification often depend on the information of the selected image in selecting the region of interest. This study propose an effective method of selecting the area of interest using the continuous digital topographic map constructed from high resolution images. The spatial information used in this research is based on the digital topographic map from 2013 to 2017 provided by the National Geographical Information Institute and the 2015 Sejong City land cover map provided by the Ministry of Environment. To verify the accuracy of the extracted area of interest, KOMPSAT-3A satellite images were used which taken on October 28, 2018 and July 7, 2018. The baseline samples for 2015 were extracted using the unchanged area of the continuous digital topographic map for 2013-2015 and the land cover map for 2015, and also extracted the baseline samples in 2018 using the unchanged area of the continuous digital topographic map for 2015-2017 and the land cover map for 2015. The redundant areas that occurred when merging continuous digital topographic maps and land cover maps were removed to prevent confusion of data. Finally, the checkpoints are generated within the region of interest, and the accuracy of the region of interest extracted from the K3A satellite images and the error matrix in 2015 and 2018 is shown, and the accuracy is approximately 93% and 72%, respectively. The accuracy of the region of interest can be used as a region of interest, and the misclassified region can be used as a reference for change detection.

CROSS-VALIDATION OF ARTIFICIAL NEURAL NETWORK FOR LANDSLIDE SUSCEPTIBILITY ANALYSIS: A CASE STUDY OF KOREA

  • LEE SARO;LEE MOUNG-JIN;WON JOONG-SUN
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.298-301
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    • 2004
  • The aim of this study is to cross-validate of spatial probability model, artificial neural network at Boun, Korea, using a Geographic Information System (GIS). Landslide locations were identified in the Boun, Janghung and Youngin areas from interpretation of aerial photographs, field surveys, and maps of the topography, soil type, forest cover and land use were constructed to spatial data-sets. The factors that influence landslide occurrence, such as slope, aspect and curvature of topography, were calculated from the topographic database. Topographic type, texture, material, drainage and effective soil thickness were extracted from the soil database, and type, diameter, age and density of forest were extracted from the forest database. Lithology was extracted from the geological database, and land use was classified from the Landsat TM image satellite image. Landslide susceptibility was analyzed using the landslide­occurrence factors by artificial neural network model. For the validation and cross-validation, the result of the analysis was applied to each study areas. The validation and cross-validate results showed satisfactory agreement between the susceptibility map and the existing data on landslide locations.

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A One-Year Analysis of Dairy Cow Diseases of Seoul Area at Hyup Dong Large Animal Clinic (협동유우진료소(協同乳牛診療所)를 중심(中心)한 서울근교(近郊) 유우질환(乳牛疾患)의 연간조사보고(年間調査報告))

  • Cheong, C.K.;Nam, J.H.;Kim, J.B.;Suh, J.S.;Choi, C.B.;Park, K.Y.
    • Korean Journal of Veterinary Research
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    • v.6 no.1
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    • pp.53-56
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    • 1966
  • Number of dairy cow patients treated at Hyup Doug Large Animal Clinic during the year July 1,1965, through June 30, 1966, were amounted to 485 cases and the result of analysis of disease incidence during one year period were us follows; 1. In the etiologic diagnostic categories, diseases caused by static mechanical abnormality were most productive and 28.1% of all diagnoses involved in this category. 2. In the topographic diagnostic categories, 39.4% of all diagnoses involved the urogenital system and were obeserved most productive. 3. As a result of each topographic diagnostic categories were subdivided into disease entities, 13.4% of all diagnoses involved the retained placenta and this were observed most productive in the miscellaneous disease enties. Next productive diseases were miscellaneous ovarian disease (10.9%), indigestion (10.3%), mastitis (8.0%) and metritis (6.8%) chronologically.

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Analysis of hydrologic chracterustucs for Milyang river basin with a GIS (GIS를 이용한 밀양강 유역의 지형학적 특성 분석)

  • 유승근;최성규;문상원
    • Spatial Information Research
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    • v.10 no.1
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    • pp.107-122
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    • 2002
  • Hydrological characteristics would be utilized to apply such as hydrologic modelling or basin management. This study is to extract hydrological characteristics through DEM and stream network analysis using a hydrologic unit map and digital topographic map in Milyang river basin. OEM and stream network was generated from digital topographic map. Especially stream network was allowed direction, stream order, and topology. As a result of the study, it shows that Milyang river has been changing geologically mature stage into old phase and the landform of Milyang river correspond to Horton-Strahler's law on morphology of stream. This methodology can be applicable to other areas related to hydrological characteristics with vector data.

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