• Title/Summary/Keyword: Topographical Images

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Generation of Digital Orthoimage using ADS40 Images (ADS40영상에 의한 수치정사영상 생성)

  • Lee, Jun-Hyuk;Lee, Young-Jin
    • Spatial Information Research
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    • v.16 no.3
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    • pp.317-330
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    • 2008
  • In this paper, the acquisition of digital imagery and the orthoimage generation were performed to set up working process. And another purpose of this thesis is to evaluate the accuracy of orthoimage by overlapping digital topographic map and digital cadastral map on it. The digital topographic map and digital cadastral map were superimposed on the orthoimage to check the accuracy as another approach of evaluation. The RMSE is ${\pm}0.364m$ in X direction and ${\pm}0.413m$ in Y direction with digital topographical maps(1/5,000). And the RMSE is ${\pm}1.283m$ in X direction and ${\pm}1.085m$ in Y direction with digital cadastral map. It is necessary for the application of a newly developed digital aerial camera to make an exact synchronization between GPS/IMU data and image data, use a technology for setting a standard image resolution and the number of ground control points.

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Biological Applications of White Light Scanning Interferometry (백색광 주사간섭계의 생물학적 응용)

  • Kim, Ki-Woo
    • Applied Microscopy
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    • v.41 no.4
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    • pp.223-228
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    • 2011
  • White light scanning interferometry has been employed to analyze surface features of diverse specimens. Long established in the field of materials engineering, the technique provides quantitative three-dimensional data as well as qualitative morphological images. It uses white light that is split and reflected from a reference mirror and an object. Merged together, the light generates interference patterns representing topographical contours of the object surface. The amplitude of the z-axis data is differentiated by gray scale. The technique allows the rapid, noncontact, and wide-field measurements for morphometry of biological specimens including chondrocytes, tooth enamel, and plant leaves. Quantification of the dimension of surface structures such as width, length, and elevation angle could be achievable by white light scanning interferometry. The light reflection from plant leaves has been assumed to be sufficient for the technique. Without special specimen preparations like conductive metal coating, the technique can be increasingly used for quantitative three-dimensional surface measurements of biological specimens.

Hydrological Analysis in Soyanggang-dam Watershed Using SLURP Model (SLURP 모형을 이용한 유출수문분석 - 소양강댐 유역을 대상으로 -)

  • Lim, Hyuk-Jin;Kwon, Hyung-Joong;Jang, Cheol-Hee;Kim, Seong-Joon
    • Journal of Korea Water Resources Association
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    • v.37 no.8
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    • pp.631-641
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    • 2004
  • The objective of this study is to test the applicability of SLURP (Semi-distributed Land Use-based Runoff Process) on Soyanggang-dam watershed. SLURP model is a conceptual semi-distributed form model that can be used to examine irrigation plan and the effects of proposed changes in water management within a basin or to see what effects external factors such as climate change or changing land cover might have on various water users. Topographical parameters were derived from DEM using TOPAZ and SLURPAZ. Monthly NDVIs were calculated from multi-temporal NOAA/AVHRR images during four years (1998 ∼ 2001). Weather elements (dew-point temperature, solar radiation, maximum/minimum temperature and relative humidify) were obtained from five meteorological stations within and near the study area. To simulate daily hydrograph during 1998 ∼ 2001, the model parameters of each land cover class were optimized by sensitivity analysis and SCE-UA method. Test result of SLURP was summarized by various statistics method (WMO volume error, Nash-Sutcliffe efficiency, mean error and coefficient of variation).

New insights into pathways of the accessory nerve and transverse cervical artery for distal selective accessory nerve blockade

  • Heo, Yanguk;Cho, Namju;Cho, Hyunho;Won, Hyung-Sun;Yang, Miyoung;Kim, Yeon-Dong
    • The Korean Journal of Pain
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    • v.33 no.1
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    • pp.48-53
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    • 2020
  • Background: The aim of this study was to clarify the topographical relationship between the accessory nerve (AN) and transverse cervical artery (TCA) to provide safe and convenient injection points for AN blockade. Methods: This study included 21 and 30 shoulders of 14 embalmed Korean adult cadavers and 15 patients, respectively, for dissection and ultrasound (US) examination. Results: The courses of the TCA and AN in the scapular region were classified into four types based on their positional relationships. Type A indicated the nerve that was medial to the artery and ran parallel without changing its location (38%). In type B (38%), the nerve was lateral to the artery and ran parallel without changing its location. In type C (19%), the nerve or artery traversed each other only once during the whole course. In type D (5%), the nerve or artery traversed each other more than twice forming a twist. At the levels of lines I-IV, the nerve was relatively close to the artery (approximately 10 mm). TCAs were observed in all specimens around the superior angle of the scapula at the level of line II, whereas they were not found below line VI. In US images of the patients, the TCA was commonly observed at the level of line II (93.3%) where all ANs and TCAs were observed in cadaveric dissection. Conclusions: The results expand the current knowledge of the relation between the AN and TCA, and provide helpful information for selective diagnostic nerve blocks in the scapular region.

3D Stereoscopic Terrain Extraction of Road Cut Failure Slope Using Unmanned Helicopter Photography System (무인 헬리콥터 사진촬영시스템을 이용한 도로 절개지 붕괴사면 3차원 입체 지형 추출)

  • Jang, Ho-Sik
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.5
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    • pp.485-491
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    • 2010
  • Acquisition of information on failure slope, which may cause apprehension of second hand damage, requires acquisition of fast and accurate topographical data and efficient expression in indirect surveying method without accessing as needed. Therefore, in this study, the images on the intended area were photographed through hovering in the air by approaching collapsed road cut slope with the use of unmanned helicopter photography system. As a result of comparing the points observed by no prism total station and the 10 coordinate points analyzed through image analysis, the averages of absolute values were shown to be 0.056m in X axis direction, 0.082m in Y axis direction and 0.066m Z axis direction. In addition, the RMSE of the error for 10 points of test points were 0.015636m in X axis direction, 0.021319m in Y axis direction and 0.018734m in Z axis direction. Therefore, this method can determine the range of slope and longitudinal and cross sections of each slope in dangerous area that cannot be approached in relational image matching method for the terrains of such collapsed cut slope.

Application of Satellite Data on Geomorphological Study of the Tidal Flats near Kum River Estuary (위성자료의 한국 금강 하구부근 조간대 지형 연구에 대한 응용)

  • 안충현;이용국;유흥룡;오재경
    • Korean Journal of Remote Sensing
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    • v.5 no.1
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    • pp.1-12
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    • 1989
  • The objective of this study is to develop the application techniques, such as geometrical correction, image overlapping etc., of LANDSAT Thematic Mapper image data especially useful to the geomorphological study of tidal flats. The developed processing techniques were applied to the Kum river estuary. The results of this study are as follows. 1) According to the analysis of the distribution and topographical profiles of the tidal flats, the geomorphological characteristics of the study area seem to be different depending on their location. 2) Even though the geomorphological changes were not always observable on the satellite images, several areas of undoubtful short-term deposition could be detected on the analytical map-image which compares two different situations of tidal flats. 3) Even though a further ditailed study is necessary, the distribution and dispersal patterns of suspended materials and sea surface temperature distribution patterns due to tidal and other meteorological conditions were analyzed by LANDSAT TM channel 3 and 6.

Micro-Landform Classification and Topographic Property of Tidal Flat in Julpo-Bay Using Satellite Image (위성영상을 이용한 줄포만 간석지의 미지형 분류와 지형적특성)

  • 조명희;조화룡
    • Korean Journal of Remote Sensing
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    • v.15 no.3
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    • pp.217-225
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    • 1999
  • Through the ISODATA method of unsupervised classification, the micro-landform of Julpo-Bay tidal flat was classified into mudflat, mixedflat, and sandflat using Landsat TM image. Each showed an apparent differences in its topographical characteristics and grain size composition. Mudflat occupied innermost part of the tidal flat, sandflat located closest to the entrance of the bay and mixed flat in the center is. For example, mudlflats are formed with flat faces and tidal channel. Topographically, mudflat consist of tidal channels and flat intermediate surface. Its average relief of them is about 2 meter. Meanwhile, sandflat comprised very flat landform with well-developed ripple marks of less than 10cm average relief. And Mixed flat stood in between. In addition, Out of 7 bands of Landsat TM images, band 5 and 7 provided the highest power level for discrimination between micro-landforms of the tidal flat. Band 4 showed a clear boundary between the land and tidal flat, and band 3 did its share by showing well a boundary between the sea surface and the tidal flat.

A base study of an Ecological Mapping technique by using GIS and Remote Sensing (GIS와 RS를 이용한 생태지도 작성기법에 관한 기초연구)

  • Yi, Gi-Chul;Lee, Won-Hwa;Yoon, Hae-Soon;Nam, Chun-Hee;Kim, Gu-Yeon;Kim, Seong-Hwan;Suh, Sang-Hyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.7 no.3
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    • pp.57-69
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    • 2004
  • This study developed an ecological mapping technique with GIS database using the analyses of existing ecological survey reports and the change detection on the Nakdong river estuary. The data which are used to establish GIS DB include 2 Landsat TM images on Nov. 31, 1984 and May 17, 1997, 1:25,000 topographical maps established by National Geography Institution and various ecological survey reports published by Busan metropolitan city government. The details for producing ecological map are as follows. At first, the current methods of ecomapping efforts and previous ecological surveys of Nakdong river estuary were carefully examined. Secondly, the land cover maps were created from the classified Landsat images of 1984 and 1997 for the spatiotemporal ecosystem analysis. Thirdly, the ecosystem was evaluated by using GIS ecological database based on the criteria of botany, zoology and water quality etc. Each criteria was reclassified into 3 stages which describe the overall quality of ecological condition. At last, the comprehensive ecological map was suggested as a prototype of ecosystem assesment and management tool with the discussion of further study. The findings of this study would be a milestone for preserving and managing the ecosystem.

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Spectroscopic Comparison of Photo-oxidation of Outside and Inside of Hair by UVB Irradiation (자외선B 조사에 의한 모발 외부와 내부의 광산화에 관한 분광학적 비교)

  • Ha, Byung-Jo
    • Applied Chemistry for Engineering
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    • v.31 no.2
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    • pp.220-225
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    • 2020
  • Hair is made of proteins containing various amino acids. Ultraviolet (UV) radiation is believed to be responsible for the most damaging effects of sunlight, and also plays an important role in hair aging. The purpose of this study was to investigate the changes in morphological and chemical structures after ultraviolet B (UVB) irradiation of human hair. The UVB-irradiated hair showed characteristic morphological and structural changes, compared to those of the normal hair. The result from a scanning electron microscope (SEM) equipped with an energy dispersive X-ray diffractometer (EDX) showed that the scale of UV-irradiated hair appeared to be rough and the amount of oxygen element was higher than that of the normal hair. Fluorescence and three dimensional (3D) topographical images were obtained by a confocal laser scanning microscope (CLSM). In 3D images, the green emission intensity of normal hair was much higher than that of fluorescing UVB-irradiated hair. The intensity of green emission reflects the intrinsic fluorescence of hair protein. Also, a fluorescent imaging method using fluorescamine reagent was used to identify the free amino groups resulting from a peptide bond breakage in UVB-irradiated hair. Strong blue fluorescence of UVB-irradiated hair, which indicates a very high level of amino groups, was observed by CLSM. Therefore, the fluorescamine as an extrinsic fluorescence could provide a useful tool to identify the peptide bond breakage in UVB-irradiated hair. Infrared image mapping was also employed to assess the cross-sections of normal and UVB-irradiated specimens to examine the oxidation of disulfide bonds. The degree of peak areas with strong absorbance for the disulfide mono-oxide was spread from the outside to the inside of hair. The spectroscopic techniques used alone, or in combination, launch new possibilities in the field of hair cosmetics.

Estimation of spatial distribution of snow depth using DInSAR of Sentinel-1 SAR satellite images (Sentinel-1 SAR 위성영상의 위상차분간섭기법(DInSAR)을 이용한 적설심의 공간분포 추정)

  • Park, Heeseong;Chung, Gunhui
    • Journal of Korea Water Resources Association
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    • v.55 no.12
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    • pp.1125-1135
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    • 2022
  • Damages by heavy snow does not occur very often, but when it does, it causes damage to a wide area. To mitigate snow damage, it is necessary to know, in advance, the depth of snow that causes damage in each region. However, snow depths are measured at observatory locations, and it is difficult to understand the spatial distribution of snow depth that causes damage in a region. To understand the spatial distribution of snow depth, the point measurements are interpolated. However, estimating spatial distribution of snow depth is not easy when the number of measured snow depth is small and topographical characteristics such as altitude are not similar. To overcome this limit, satellite images such as Synthetic Aperture Radar (SAR) can be analyzed using Differential Interferometric SAR (DInSAR) method. DInSAR uses two different SAR images measured at two different times, and is generally used to track minor changes in topography. In this study, the spatial distribution of snow depth was estimated by DInSAR analysis using dual polarimetric IW mode C-band SAR data of Sentinel-1B satellite operated by the European Space Agency (ESA). In addition, snow depth was estimated using geostationary satellite Chollian-2 (GK-2A) to compare with the snow depth from DInSAR method. As a result, the accuracy of snow cover estimation in terms with grids was about 0.92% for DInSAR and about 0.71% for GK-2A, indicating high applicability of DInSAR method. Although there were cases of overestimation of the snow depth, sufficient information was provided for estimating the spatial distribution of the snow depth. And this will be helpful in understanding regional damage-causing snow depth.