• Title/Summary/Keyword: terrain change

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3-Dimensional Terrain Model of Ruins Distribution Using GIS (GIS를 이용한 유적분포 3차원 지형모델)

  • Kwak, Young-Joo;Kang, In-Joon;Jang, Yong-Gu;Kang, Young-Shin;Kim, Sang-Seok
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.4 s.31
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    • pp.27-33
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    • 2004
  • Recently, as a part of NGIS project, cultural-assets digital map is produced by cultural properties administration and local autonomous entities. Cultural-assets unified GIS(Geographic Information System) is essential to cultural properties managers md other organizations which are executing land related business for appling it at planning stage. With explosive national land developments, it has been obligated to implement surface survey by the cultural properties protection Art. In this paper, the authors used the district of Sachon city and made 3D terrain model using digital map which is made of 1/5000 stale. Moreover, the authors improved to RDBMS(Relational Database Management System) structure and remodeled the existing DB design in detail, and also tried recovery of past sea level, based on researches about the water level of southern area. By recover past sea level. the shell mound, apart from lever is actually near lever at past, and it make sure its nature. The authors suggested to realize shape and kind of remains which have 3D information of accuracy and actualization from surface-surveying to excavation.

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The Effects of Declination and Curvature Weight in DEM (수치표고모형에서 경사와 곡률경중율의 영향)

  • Yang, In-Tae;Choi, Seung-Pil;Kwon, Hyun;Kim, Wook-Nam
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.8 no.2
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    • pp.45-51
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    • 1990
  • DEM must have a high accuracy against the actual topographic model. A model which can compute heights responding to random plane position by using of the topographic data and interpolation must be constructed. Interpolation affected by the accuraccy of the observations included noise, which affected by the slop and curvature weight. Data smoothing is a method to reduce the noise. Average declination and area ratio are variable which result similarity in according to slope. But in local area, area ratio well shows a local change. This study try to classify the terrain by the declination to analysis the effects of the declination and curvature weights, and then to represent the most probable model. The result are following : In terrain classification by the slop, p16 and p24 were fitted in the plane surface fit p16 and S in the varying surface, and S and p24 in the irregular surface in classification by curvature, p24 and S were fitted in the plane or varying surface, and p16 in the irregular surface In case of hybrid, p16, p24 and S are fitted in the plane, varying and irregular surface respectively. Smoothing is the most effective in case of slope of 50 persentage and of curvature weight of 0.0015.

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Quantifying the Spatial Heterogeneity of the Land Surface Parameters at the Two Contrasting KoFlux Sites by Semivariogram (세미베리오그램을 이용한 KoFlux 광릉(산림) 및 해남(농경지) 관측지 지면모수의 공간 비균질성 정량화)

  • Moon, Sang-Ki;Ryu, Young-Ryel;Lee, Dong-Ho;Kim, Joon;Lim, Jong-Hwan
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.2
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    • pp.140-148
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    • 2007
  • The remote sensing observations of land surface properties are inevitably influenced by the landscape heterogeneity. In this paper, we introduce a geostatistical technique to provide a quantitative interpretation of landscape heterogeneity in terms of key land surface parameters. The study areas consist of the two KoFlux sites: (1) the Gwangneung site, covered with temperate mixed forests on a complex terrain, and (2) the Haenam site with mixed croplands on a relatively flat terrain. The semivariogram and fractal analyses were performed for both sites to characterize the spatial heterogeneity of two radiation parameters, i.e., land surface temperature (LST) and albedo. These parameters are the main factors affecting the reflected longwave and shortwave radiation components from the two study sites. We derived them from the high-resolution Landsat ETM+ satellite images collected on 23 Sep. 2001 and 14 Feb. 2002. The results of our analysis show that the characteristic scales of albedo was >1 km at the Gwangneung site and approximately 0.3 km at the Haenam site. For LST, the scale of heterogeneity was also >1 km at the Gwangneung site and >0.6 to 1.0 km at the Haenam site. At both sites, there was little change in the characteristic scales of the two parameters between the two different seasons.

Automatic Geo-referencing of Sequential Drone Images Using Linear Features and Distinct Points (선형과 특징점을 이용한 연속적인 드론영상의 자동기하보정)

  • Choi, Han Seung;Kim, Eui Myoung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.1
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    • pp.19-28
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    • 2019
  • Images captured by drone have the advantage of quickly constructing spatial information in small areas and are applied to fields that require quick decision making. If an image registration technique that can automatically register the drone image on the ortho-image with the ground coordinate system is applied, it can be used for various analyses. In this study, a methodology for geo-referencing of a single image and sequential images using drones was proposed even if they differ in spatio-temporal resolution using linear features and distinct points. Through the method using linear features, projective transformation parameters for the initial geo-referencing between images were determined, and then finally the geo-referencing of the image was performed through the template matching for distinct points that can be extracted from the images. Experimental results showed that the accuracy of the geo-referencing was high in an area where relief displacement of the terrain was not large. On the other hand, there were some errors in the quantitative aspect of the area where the change of the terrain was large. However, it was considered that the results of geo-referencing of the sequential images could be fully utilized for the qualitative analysis.

A Study on the Effect of Collector Well on the Landcreep Slope (땅밀림 비탈면내 집수정 설치 효과 연구)

  • Jeon, Byeong Chu;Lee, Su Gon
    • The Journal of Engineering Geology
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    • v.29 no.2
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    • pp.123-136
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    • 2019
  • This study examines the effect of collector well installed to reduce groundwater level in the regions with the occurrence of landcreep, a soil mass movement triggered by instability on slopes. Slopes are prone to failure as a result of instability caused by its internal, topographic and geological properties as well as due to external factors such as rainfall and earthquake. In Korea during the rain season, rainfall infiltration affects the groundwater level in soil, building up porewater pressure and load, and finally drives slopes to collapse. Slope failure caused by rainfall infiltration has been leading to a drastic forest degradation. The studied slope is located adjacent to a valley, its terrain corresponds to piedmont gentle slope, while the upper part of the failure surface is steep. After reinforcing the terrain where landcreep had occurred and installing collector well on the slope, we measured the changes in the groundwater level. In order to analyze the relationship between the well and the slope, we calculated the ratio of groundwater level to rainfall before and after the installation of the collector well. As a result, it is confirmed that the ratio increases after the installation of the well, which in turn reduces the groundwater level. Analysis of the change in groundwater level after 3, 7, 15 days antecedent rainfall showed that the higher the overall groundwater level, the less the value ($r_p$) of groundwater level-rainfall ratio is, while the value becomes relatively greater when the groundwater level is low. In particular, if a slope has a large catchment basin as is in the case of the studied site, antecedent rainfall affects groundwater level in the order of 3 < 7 < 15 days.

Comparison of Multi-angle TerraSAR-X Staring Mode Image Registration Method through Coarse to Fine Step (Coarse to Fine 단계를 통한 TerraSAR-X Staring Mode 다중 관측각 영상 정합기법 비교 분석)

  • Lee, Dongjun;Kim, Sang-Wan
    • Korean Journal of Remote Sensing
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    • v.37 no.3
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    • pp.475-491
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    • 2021
  • With the recent increase in available high-resolution (< ~1 m) satellite SAR images, the demand for precise registration of SAR images is increasing in various fields including change detection. The registration between high-resolution SAR images acquired in different look angle is difficult due to speckle noise and geometric distortion caused by the characteristics of SAR images. In this study, registration is performed in two stages, coarse and fine, using the x-band SAR data imaged at staring spotlight mode of TerraSAR-X. For the coarse registration, a method combining the adaptive sampling method and SAR-SIFT (Scale Invariant Feature Transform) is applied, and three rigid methods (NCC: Normalized Cross Correlation, Phase Congruency-NCC, MI: Mutual Information) and one non-rigid (Gefolki: Geoscience extended Flow Optical Flow Lucas-Kanade Iterative), for the fine registration stage, was performed for performance comparison. The results were compared by using RMSE (Root Mean Square Error) and FSIM (Feature Similarity) index, and all rigid models showed poor results in all image combinations. It is confirmed that the rigid models have a large registration error in the rugged terrain area. As a result of applying the Gefolki algorithm, it was confirmed that the RMSE of Gefolki showed the best result as a 1~3 pixels, and the FSIM index also obtained a higher value than 0.02~0.03 compared to other rigid methods. It was confirmed that the mis-registration due to terrain effect could be sufficiently reduced by the Gefolki algorithm.

A Study on the Characteristics and Values of Unregistered Private Households in Cholla Province, Chungcheong Province, Gyeongsang Province (향토문화유산 중 충청지역 민가정원의 역사정원으로서의 가치와 보존 방향)

  • Jin, Hye-young;Park, So-Hyun;Shin, Hyun-Sil
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.39 no.4
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    • pp.77-84
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    • 2021
  • This paper attempted to examine the value of private house garden as a historical garden among local cultural heritages remaining in Chungcheong-do Province. To this end, the following conclusions were drawn through the framework of value analysis in which the contents of Ji Cheng's Yuanye of China, Tachibana Toshitsuna's Sakuteiki in Japan, and HISTORIC GARDENS THE FLORENCE CHARTER 1981 were applied to target sites. First, local cultural heritage belong to unregistered cultural heritage, and a total of 616 local cultural heritages in Chungcheong-do Province were identified, and Cheongju City possesses the largest number of local cultural heritages. Most of the local cultural heritages are distributed in ancient capital or adjacent to it, and five of the local heritages are related to historical garden. Second, the target sites were old houses constructed during the Joseon Dynasty with a long history, and although there were few changes in spatial division, the scale of some gardens and outer yard spaces was reduced due to urban planning, etc. Third, the target site is Sangjihapui(相地合宜) and Inchacheui(因借體宜) in location and space division, so the space is divided according to the surrounding terrain and the landscape is naturally drawn to construct a garden. Fourth, the garden of the target site has a structural value of a garden that is Jeongihapui(精而合宜) and Gyoideukche(巧而得體) as it is subtle and naturally constructed with the garden by grasping the surrounding terrain. Fifth, for the continuous preservation of historical garden, it is necessary to strengthen the already enacted local cultural heritage ordinance, and to establish a documentary project for each spatial component and a plan for climate change.

Mountain Meteorology Data for Forest Disaster Prevention and Forest Management (산림재해 방지와 산림관리를 위한 산악기상정보)

  • Keunchang, Jang;Sunghyun, Min;Inhye, Kim;Junghwa, Chun;Myoungsoo, Won
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.346-352
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    • 2022
  • Mountain meteorology in South Korea that is covered mountains with complex terrain is important for understanding and managing the forest disaster and forest ecosystems. In particular, recent changes in dryness and/or rainfall intensity due to climate change may cause an increase in the possibility of forest disasters. Therefore, accurate monitoring of mountain meteorology is needed for efficient forest management. Korea Forest Service (KFS) is establishing the Automatic Mountain Meteorology Observation Stations (AMOS) in the mountain regions since 2012. 464 AMOSs are observing various meteorological variables such as air temperature, relative humidity, wind speed and direction, precipitation, soil temperature, and air pressure for every minute, which is conducted the quality control (QC) to retain data reliability. QC process includes the physical limit test, step test, internal consistency test, persistence test, climate range test, and median filter test. All of AMOS observations are open to use, which can be found from the Korean Mountain Meteorology Information System (KoMIS, http://mtweather.nifos.go.kr/) of the National Institute of Forest Science and the Public Data Portal (https://public.go.kr/). AMOS observations with guaranteed quality can be used in various forest fields including the public safety, forest recreation, forest leisure activities, etc., and can contribute to the advancement of forest science and technology. In this paper, a series of processes are introduced to collect and use the AMOS dataset in the mountain region in South Korea.

Future PMPs projection according to precipitation variation under RCP 8.5 climate change scenario (RCP 8.5 기후변화 시나리오의 강수량 변화에 따른 미래 PMPs의 전망)

  • Lee, Okjeong;Park, Myungwoo;Lee, Jeonghoon;Kim, Sangdan
    • Journal of Korea Water Resources Association
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    • v.49 no.2
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    • pp.107-119
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    • 2016
  • Since future climate scenarios indicate that extreme precipitation events will intensity, probable maximum precipitations (PMPs) without being taken climate change into account are very likely to be underestimated. In this study future PMPs in accordance with the variation of future rainfall are estimated. The hydro-meteorologic method is used to calculate PMPs. The orographic transposition factor is applied in place of the conventional terrain impact factor which has been used in previous PMPs estimation reports. Future DADs are indirectly obtained by using bias-correction and moving-averaged changing factor method based on daily precipitation projection under KMA RCM (HEDGEM3-RA) RCP 8.5 climate change scenario. As a result, future PMPs were found to increase and the spatially-averaged annual PMPs increase rate in 4-hour and $25km^2$ was projected to be 3 mm by 2045. In addition, the increased rate of future PMPs is growing increasingly in the future, but it is thought that the uncertainty of estimating PMPs caused by future precipitation projections is also increased in the distant future.

Development of Plant Phenology and Snow Cover Detection Technique in Mountains using Internet Protocol Camera System (무인카메라 기반 산악지역 식물계절 및 적설 탐지 기술 개발)

  • Keunchang, Jang;Jea-Chul, Kim;Junghwa, Chun;Seokil, Jang;Chi Hyeon, Ahn;Bong Cheol, Kim
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.318-329
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    • 2022
  • Plant phenology including flowering, leaf unfolding, and leaf coloring in a forest is important to understand the forest ecosystem. Temperature rise due to recent climate change, however, can lead to plant phenology change as well as snowfall in winter season. Therefore, accurate monitoring of forest environment changes such as plant phenology and snow cover is essential to understand the climate change effect on forest management. These changes can monitor using a digital camera system. This paper introduces the detection methods for plant phenology and snow cover at the mountain region using an unmanned camera system that is a way to monitor the change of forest environment. In this study, the Automatic Mountain Meteorology Stations (AMOS) operated by Korea Forest Service (KFS) were selected as the testbed sites in order to systematize the plant phenology and snow cover detection in complex mountain areas. Multi-directional Internet Protocol (IP) camera system that is a kind of unmanned camera was installed at AMOS located in Seoul, Pyeongchang, Geochang, and Uljin. To detect the forest plant phenology and snow cover, the Red-Green-Blue (RGB) analysis based on the IP camera imagery was developed. The results produced by using image analysis captured from IP camera showed good performance in comparison with in-situ data. This result indicates that the utilization technique of IP camera system can capture the forest environment effectively and can be applied to various forest fields such as secure safety, forest ecosystem and disaster management, forestry, etc.