• Journal of the Korean GEO-environmental Society
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• v.22 no.2
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• pp.35-39
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• 2021

Photogrammetry using drone can produce high-resolution ortho image and acquire high-accuracy 3D information, which is useful. Therefore, this study attempted to determine the possibility of using drone-photogrammetry in park construction by producing a topographic map using drone-photogrammetry and analyzing the problems and accuracy generated during production. For this purpose, we created ortho image and DSM (digital surface model) using drone images and created topographic status map by vectorizing them. Accuracy was compared based on topographic status map by GPS (global positioning system) and TS (total station). The resulting of analyzing mean of the residuals at check points showed that 0.044 m in plane and 0.066 m in elevation, satisfying the tolerance range of 1/1,000 numerical maps, and result of compared lake size showed a difference of about 4.4%. On the other hand, it was difficult to obtain accurate height values for terrain in which existed vegetation when producing the topographic map, and in the case of underground buried objects, it is not possible to confirm it in the image, so direct spatial information acquisition was necessary. Therefore, it is judged that the topographic status map using drone photogrammetry can be efficiently constructed if direct spatial data acquisition is achieved for some terrain.

• The Journal of Engineering Geology
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• v.21 no.3
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• pp.199-212
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• 2011

To investigate the causes of ground deformation around the Dogye coal waste depot in Samcheok city, Gangwon Province, we undertook a field survey and performed boring tests and a topographic analysis using maps compiled in various years. The results of boring tests and analyses of ground fractures indicate that the thickness of the soil layer ranges from 9 to 28.5 m and that ground deformation has occurred to the $240{\sim}250^{\circ}$ direction. The topographic analysis revealed that the topography of the site has changed continuously due to the dumping of coal waste. The causes of ground deformation, investigated by both field surveys and the topographic analysis, were the thick layer of soil at this site, the loading weight of coal waste, and the excavation at the lower part of the slope.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.129-134
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• 2005

Ths study was carried out to understand the geo-topographical characteristics of the landslide area (1.5 ha) in Maeri, Sangdong-myeon, Gimhaesi, Gyeongsangnam-do. The bedrock of the landslide area was diollites and the area in and around the upper slope with the scattered talus was composed of Masanam originated from Igneous rocks. The landslide occurred in 19th of April, 2004 and the amount of rainfall for 3 days before the landslide was 74mm. The landslide by land creeping in this area was mainly attributed to geo-topographical characteristics such as well developed colluvial and/or weathered soils, and land cutting in lower slope, although the landslide could be affected by the rainfall. The type of the landslide can be classified into the land creeping by concave colluvial soils.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.321-325
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• 2003

The technology for the multi-dimensional terrain perspective view can be used as an important factors in planning and designing for the various construction projects. In this study, the stereo image perspective view has been generated for the multi-dimension analysis by combining useful digital map and remotely sensed satellite images. In the course of experimenting with the multi-dimensional topography generated by the combination of the front-projected image by the precise GCP and DEM from the contour line, the technology has been developed to offer the multi-dimensional access to the potential construction sites from the nearby main roads. This stereo image bird's eye view has made it possible to make multi-dimensional analysis on the terrain, which provides real time virtual access to the designated construction sites and will be a versatile application for development planning and construction projects.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.3
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• pp.1-8
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• 2002

The technology for the three-dimensional terrain perspective view can be used as an important factor in planning and designing for the various construction projects. In this study, the stereo image perspective view has been generated for the multi-dimension analysis by combining useful digital map and remotely sensed satellite images. In the course of experimenting with the three-dimensional topography generated by the combination of the orthopimage by the precise GCP and DEM from the contour line, the technology has been developed to offer the multi-dimensional access to the potential construction sites from the nearby main roads. This stereo image bird's eye view has made it possible to make multi-dimensional analysis on the terrain, which provides real-time virtual access to the designated construction sites and will be a versatile application for development planning and construction projects.

• Journal of The Geomorphological Association of Korea
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• v.19 no.4
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• pp.97-108
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• 2012

There exist plenty of geomorphological resources in Haean Basin, Yonghwasan Mt., and Gandong Basin in Eastern DMZ area in Gangwon Province which can be used as geotourism resources. Meticulous strategies are necessary to improve the geotourism bases in such a mountainous region. Potential geosites including Yongneup and Simjeog wetlands are nearby, so it is necessary to include these geosites when planning geotourism courses. The values of these sites coinciding with the goal of geopark are as follows: this region shows contrasting landforms derived from distinctive rocks such as gneiss and biotite granite, and there are many landforms derived from differential weathering of granite too. They can be used to explain the developmental history of numerous basin structures in entire Korean peninsula.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.44-55
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• 2003

The wetland in the city could be mainly divided into the deep water type and the abandoned paddy type, so this study was conducted to analyze characteristics between the two types of the wetland. The former sample site was located near the Olympic village in Songpa-gu of Seoul, and the latter sample site was in front of the Mt. Bukhan fortress in Eunpyeong-gu of Seoul. The actual vegetation, vascular plants, and avian fauna were researched. In the actual vegetation, the deep water type had the broad surface of water and the emerged plant as Phragmites communis have grown widely, but the abandoned paddy type had the narrow sur-face of water and hydrophyte as Persicaria thunbergii have grown widely. It might be judged because the water depth of the abandoned paddy type were shallow wholly. And the floating-leaved plants and the free-floating planktonic plants were not observed such as Nymphaea tetragona var. angusta, Lemna paucicostata in the abandoned paddy type wetland. The wild birds were mainly observed at the edge of the wetland(at the edge of woodland) in the abandoned paddy type, but were observed equally in the deep water type. 28 families 433 species were observed at the former site and 32 families 365 species were observed at latter site. It was judged that the various topographical structure(habitat diversity) might make all items various.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.45-49
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• 2011

This research was carried out to investigate frost damage of mulberry tree (Morus alba) according to topographic characteristics in Buan province. The first bud-break, leafing, blooming and harvest date of mulberry tree in 2010 were two, four, fourteen and eight days later than those in 2009, respectively. These results were that daily mean temperature during March and April in 2010 were lower than those in 2009 by $2.3^{\circ}C$ and $2.4^{\circ}C$. Frost damage of orchards at flat-bottomed valley, flat near hill and lake, and plain were 50.0%,12.0%, and 4.2%, respectively. Also, frost damage of branch of below 15 mm in diameter was serious than that of branch over 16 mm, but orchard at flat-bottomed valley was high as the range of 46.2~54.0%. These results in 2010 were caused by occurrence of below zero temperatures in leafing stage. Since then, many shoots came out at accessary bud on proximal and the top part of the branches. Therefore, frost damage of mulberry tree in Buan province in 2010 was caused by occurrence of below zero temperatures on April and topographic characteristics of orchard.

• The Journal of the Petrological Society of Korea
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• v.26 no.3
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• pp.167-181
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• 2017

Cheongryangsan area ($49.51km^2$) has been designated as the Provincial Park in 1982, because it has magnificent aspect and seasonally spectacular landscapes. Especially, Cheongryangsa sitey ($4.09km^2$) has been designated as Noted Scenery No. 23 in 2007, because it has the same topographical landscape as rock cliffs, rock peaks and caves. The most spectacular landscapes are exhibited in the Cheongryangsan Conglomerate and Osipbong Basalt. There are twelve rock peaks on the ridges of the two strata, and many rock cliffs in the several valleys of strata, in which a few caves are formed by differential weathering and erosion. The valleys, in which flow Cheongryang, Bukgok and Cheonae streams, are classified as fault valleys along WNW-ESE faults. The rock cliffs were generated from vertical joints parallel to WNW-ESE faults in the two strata, and the caves were formed by differential weathering and erosion along bedding of sandstones and shales intercalated in the conglomerates. The rock peaks are landscapes formed by differential erosion along crossed vertical joints in the ridges. The vertical joints are developed subparallel to two WNW-ESE faults and a NNE-WWS fault. Therefore the topographical features are caused by existence of the faults and Lithologic difference in the Cheongryangsan Conglomerate and Osipbong Basalt, and by differential weathering and erosion along them.

• Journal of the Korean Geographical Society
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• v.48 no.2
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• pp.204-217
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• 2013

This study shows the geomorphological processes of Yuga alluvial fan at Dalseong-gun, Daegu in Korea, based on characteristics of geomorphological surfaces, analysis of geomorphological deposits and OSL age dating. Alluvial fans of this area are classified into three surfaces(YG-F1, YG-F2, YG-F3) and were formed by the depositional processes resulting from the changes in hydraulic geometry of flowing water which was a stream flowing out of mountains debouched on to a plain, not by a sudden decrease in surface gradient of river bed. YG-F3 surface, about 110,000 yr B.P.(MIS 5.4), was formed as Yongri river deposited a lot of debris. This result was due to the process that the deposition took place actively with the upward of base level as the last interglacial period began. Later, the denudation of the river valley and geomorphological surface constantly occurred and the local and seasonal changes were found in precipitation and stream discharge with the beginning of the interstadial of the last glacial stages(MIS 3), leading to YG-F2 formed by debris flow, earth flow, mud flow and stream flow. Then, short-term climate changes and temporal climate events repeatedly caused aggradation and denudation over time and going through these processes, YG-F1 is believed to have been made by earth flow or mudflow during the last glacial maximum(MIS 2).