• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.584-584
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• 2015

최근 기후변화로 인한 국지성 집중호우와 태풍 등으로 홍수피해가 급증하고 있음에 따라 침수지역에 대한 공간적인 분석과 사전 예측으로 피해를 최소화하려는 노력이 필요하다. 따라서 본 연구에서는 소유역 별 평균화된 매개변수로 홍수량을 산정하는 집중형 모형이 아닌 분포형 모형을 적용하여 남강댐 유역의 유출량 산정 및 침수예측을 분석하였다. 분포형 모형은 격자체계를 기반으로 유역에 각 격자별 공간적 특성이 반영된 매개변수를 적용하므로 유역의 특성을 효과적으로 반영하므로 집중형 모형보다 정확한 해석이 가능하다. DEM, 토양도, 토지피복도 등의 격자크기 $240{\times}240$의 지형공간 자료를 ArcGIS를 이용하여 남강댐유역의 Flow direction, 경사도, 하도경사, 불투수율, 유효공극률, 조도계수, 토양심도, 수리전도도, 토양흡인수두 등의 수문매개변수를 추출하였다. 강우 자료의 경우 티센(Thiessen)법에 의해 선정된 남강댐유역 주변의 장수, 거창, 진주, 합천, 산청, 남원 강우관측소의 100년빈도 확률강우량 산정하여 24시간 확률강우를 3분위 Huff 분포시킨 후 강우의 공간적 통계특성을 반영하는 크리깅(Kriging)기법으로 적용하여 강우보간을 실시하였다. 침수예측을 위해 $Vflo^{TM}$모형을 이용해 48시간의 강우모의시간 홍수수문곡선 유도 및 홍수량 산정하였으며, 시간에 따른 침수 시뮬레이션하여 침수예측도를 작성하였다. 작성 시 침수심의 정도에 따라 5개의 구간으로 분류해 침수위험지역을 확인 할 수 있도록 도식화하였다. 본 연구에서는 남강댐유역의 침수위험지역을 개략적으로 예측할 수 있었으며, 추후 연구에서는 보다 조밀한 격자크기와 강우를 이용하여 분석한다면 향후 피난 정보 제공과 홍수재해지도 작성, 홍수방지 시설물 건설 또는 홍수보험계획 등에 응용이 될 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.225-225
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• 2019

건물, 차량, 사회인프라시설과 달리 농작물이란 물리적인 시설이 아닌 농업경제 활동의 결과물로서 최종적으로 판매를 통해 수익을 창출하는 행위에서 재난으로 인하여 지장을 받게 되는 경제적 피해가 고려되어야 한다. 이를 위해 본 연구는 홍수로 인한 농작물 피해를 "생산비 매몰비용"과 "순수익 손해"를 농작물 피해추정의 척도로 하였다. 생산비 매몰비용이란 경작시작부터 피해발생까지 투입된 생산비의 회수불가에 따른 피해이며, 순수익 손해란 피해발생에 따른 기대 순수익 하락에 따른 피해를 의미한다. 다양한 작물 가운데 10종의 대표작물을 선택하고, 각 작물의 표준생산비와 표준순수익을 농업생산 및 수익과 관련한 통계자료로부터 결정하였다. 이로부터 생육경과율과 홍수 발생시기(6~9월)를 고려하여 월별 투입생산비 및 기대순수익을 결정하였다. 대상지역 내 재난에 노출된 작물정보를 정의하는 농작물 인벤토리는 농림축산식품부에서 제작된 스마트 팜 맵(농경지 전자지도)을 활용하였고, 다양한 작물이 혼재된 밭의 경우 농업면적조사 결과를 토대로 결정한 밭작물 재배현황비를 고려하였다. 홍수에 따른 취약성을 설명하는 농작물 손상함수는 영향인자는 침수심, 침수기간이며, 이를 기준으로 한 손상함수는 농림부의 농업재해피해조사요령과 일본 치수경제조사메뉴얼을 참고하여 제시하였다. 본 연구에서 제시한 농작물 피해 추정 방법은 기존 방법인 다차원 홍수피해산정법(MD-FDA)과 비교할 때 대표작물의 현실화, 국내 실정을 고려한 손상함수, 그리고 면적 기반의 원단위를 사용함으로써 실무적으로 명확하고 실용적으로 사용될 것으로 기대된다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.4
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• pp.211-218
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• 2019

The Ministry of Land, Infrastructure and Transport is planning to launch CAS-500 (Compact Advanced Satellite 500) 1 and 2 in 2019 and 2020. Satellite image information collected through CAS-500 can be used in various fields such as global environmental monitoring, topographic map production, analysis for disaster prevention. In order to utilize in various fields like this, it is important to get the location accuracy of the satellite image. In order to establish the precise geometry of the satellite image, it is necessary to establish a precise sensor model using the GCP (Ground Control Point). In order to utilize various fields, step - by - step automation for orthoimage construction is required. To do this, a database of satellite image GCP chip should be structured systematically. Therefore, in this study, we will analyze various techniques for automatic GCP extraction for precise geometry of satellite images.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.5
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• pp.927-940
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• 2017

Landslide has been a major disaster in Indonesia, and recent climate change and indiscriminate urban development around the mountains have increased landslide risks. Java Island, Indonesia, where more than half of Indonesia's population lives, is experiencing a great deal of damage due to frequent landslides. However, even in such a dangerous situation, the number of inhabitants residing in the landslide-prone area increases year by year, and it is necessary to develop a technique for analyzing landslide-hazardous and vulnerable areas. In this regard, this study aims to evaluate landslide susceptibility of Java, an island of Indonesia, by using GIS-based spatial prediction models. We constructed the geospatial database such as landslide locations, topography, hydrology, soil type, and land cover over the study area and created spatial prediction models by applying Weight of Evidence (WoE), decision trees algorithm and artificial neural network. The three models showed prediction accuracy of 66.95%, 67.04%, and 69.67%, respectively. The results of the study are expected to be useful for prevention of landslide damage for the future and landslide disaster management policies in Indonesia.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.634-634
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• 2015

최근 국지성 호우와 잦은 태풍으로 인한 돌발홍수가 빈번하게 발생하여 도심지에서의 호안유실과 범람으로 많은 외수침수의 피해가 발생하고 있다. 또한 기후변화에 따른 강우량의 증가와 집중호우로 인한 홍수 피해는 지속적으로 증가할 것으로 예상됨에 따라 대하천 유역을 중심으로 홍수범람예측 연구가 활발히 진행되고 있지만 대하천을 제외한 지방 중소하천의 연구가 미비한 실정이다. 이에 본 연구에서는 지방 중소하천 중 태풍과 집중호우의 영향이 많은 제주지역의 주요 하천 중의 하나인 한천 유역을 테스트베드로 선정하여 연구를 진행하였다. 한천은 강우 시에만 유출이 발생하는 건천으로, 집중호우 시 암반하상 조건, 복개, 교각 등으로 수위가 국부적으로 급격히 상승하는 경우가 있었다. 그리고 한천 하류부에는 도심이 위치하고 있어 돌발홍수 발생 시 막대한 피해가 발생한다. 이에 따라 홍수 피해를 줄이기 위한 제도화, 정책결정 등의 구조적 해결방안과 홍수 피해의 규모와 원인을 분석하는 비구조적 해결방안에 대한 연구가 시급하다. 따라서 본 연구에서는 홍수범람 등으로 인한 홍수 피해규모를 산정하여 각 정부부처 및 유관기관, 지자체에서 빠른 정책결정을 내릴 수 있는 자료를 제공하는 목적으로 제주도의 특성을 고려한 홍수범람위험도 산정 알고리즘을 개발하고자 한다. 본 연구에서는 제주 한천유역의 단면 자료와 빈도별 홍수량 자료를 이용하여 HEC-RAS 모형으로 수리학적 흐름특성 모의를 실사하였다. 모의된 결과를 바탕으로 ArcGIS 소프트웨어인 ESRI사의 ArcMap을 이용하여 빈도별 홍수위 자료와 제주지역 수치표고모형 자료를 활용한 빈도별 홍수범람지도를 산정하고, 좌안과 우안의 제방고로부터 위험도를 산정하여 홍수범람위험도를 각각 구축하였다. 구축된 결과를 이용하여 분석하고자하는 해당 빈도의 홍수위와 홍수량이 발생할 때의 피해지역을 예측하였으며, 예측된 지역과 제주시의 공시지가 자료를 중첩하여 피해지역에 대한 피해액을 산정하였다. 본 연구의 알고리즘을 적용한 2007년 태풍 '나리' 사상의 경우와 비교한 결과, '나리' 사상의 침수 흔적도와 유사한 홍수범람지도를 획득 할 수 있었으며, 모의된 유역의 하천 복개구간을 중심으로 홍수범람이 발생한다는 점과 우안보다 좌안에서의 홍수범람위험도와 피해액이 더 크게 나타난 점 등의 홍수범람 특성을 파악할 수 있었다. 본 연구에서 제시된 기법을 이용할 경우, 홍수에 의한 취약지에 대한 제방 설계 강화, 하천의 보수 정비 등 정책적 결정에 사용될 수 있을 것이며, 실시간 자료제공, 재해정보시스템 등에 적용하여 홍수범람 피해를 줄일 수 있는 기반기술이 될 것으로 사료된다.

• Economic and Environmental Geology
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• v.54 no.1
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• pp.91-103
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• 2021

In order to estimate the vertical and horizontal structural in the Yangsan fault core line (Naengsuri area, Pohang), we carried out gravity field measurements and interpretation procedures such as Euler deconvolution method and curvature analysis in addition to the forward modelling technique (i.e. IGMAS+). We found a prominent gravity difference of more than 1.5 mGal across the fault core. This indicates a distinct density difference between the western and eastern crustal area across the Yangsan fault line. Comparing this gravity field interpretation with other existent geologic and geophysical survey data (e.g. LiDAR, trenching, electric resistivity measurements), It is concluded that (1) the prominent gravity difference is caused by the density difference of about 0.1 g/㎤ between the Bulguksa Granite in the west and the Cretaceous Sandstone in the east side, (2) the fault core is elongated vertically into a depth of about 2,000 meters and extended horizontally 3,000 meters to the NNE direction from Naengsuri area. Our results present that the gravity field method is a very effective tool to estimate a three -dimensional image of the active fault core.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.479-495
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• 2021

To improve on the efficient management of forest resources, it is necessary to create a forest soil map, which represents a comprehensive database of forest lands. Although a 1:25,000 scale forest site map has been used in Korea, the need for a large-scale forest soil map with high precision and information on forest lands that is specialized for individual purposes has been identified. Moreover, to keep pace with the advancement in forest management and transition to a digital society, it is essential to develop a method for constructing new forest soil maps that can diversify its use. Therefore, this paper presented a developmental process and used a 1:5,000 scale forest soil map to propose future directions. National maps showing the soil type, depth, and texture were produced based on the survey and analysis of forest soils, followed by the Forest Land Soil Map (1:5,000) Production Standard Manual. Alternatively, forest soil map data were the basis on which various other maps that can be used to prevent and predict forest disasters and evaluate environmental capacities were developed. Accordingly, ways to provide appropriate information to achieve the national forest plan, secure forestry big data, and accomplish sustainable forest management that corresponds to the national development plan are proposed based on results from the current study.

• Journal of The Geomorphological Association of Korea
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• v.20 no.1
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• pp.85-96
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• 2013

This study collected national secondary and tertiary nationwide natural environment survey data of the National Institute of Environmental Research as well as the National Park's secondary and tertiary natural resource research data executed by the Korea National Park Service. The data collection is aimed at reclassification the geomorphological landscape resources of each park in varying types. The results generated a total of 3,169 geomorphological landscape resources within all the national parks. Among all the geomorphological landscape resources, 794 landscape resources were judged as Level I, which accounts for 36.9%. Next, 546 landscape resources were judged as Level II, or 25.3%, and 459 landscape resources judged as Level III, or 21.3%. Lastly, 191 landscape resources were judged as Level IV, having the lowest conservation level, or 8.9%. The number of Level I landscape resources for each national park includes 207 sites on Seoraksan, 92 sites on Dadohaehaesang Park, 84 sites on Jirisan, and 60 sites at the Taeanhaean, respectively. Dadohaehaesang National Park, Seoraksan National Park, Taeanhaean National Park, Jirisan National Park, Songnisan National Park, and Gyeryongsan National Park were evaluated as national parks having excellent landscape resources. To use these excellent landscape resources, there is a need to increase visitors' satisfaction and increase their interest in and understanding of landscape resources. To achieve this, a landscape viewpoint map must be composed and installed at the entrance or at certain points to provide visitors with useful information regarding the geomorphological landscape resources.

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.1
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• pp.87-107
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• 2005

Land Remote Sensing' is defined as the science (and to some extent, art) of acquiring information about the Earth's surface without actually being in contact with it. Narrowly speaking, this is done by sensing and recording reflected or emitted energy and processing, analyzing, and applying that information. Remote sensing technology was initially developed with certain purposes in mind ie. military and environmental observation. However, after 1970s, as these high-technologies were taught to private industries, remote sensing began to be more commercialized. Recently, we are witnessing a 0.61-meter high-resolution satellite image on a free market. While privatization of land remote sensing has enabled one to use this information for disaster prevention, map creation, resource exploration and more, it can also create serious threat to a sensed nation's national security, if such high resolution images fall into a hostile group ie. terrorists. The United States, a leading nation for land remote sensing technology, has been preparing and developing legislative control measures against the remote sensing industry, and has successfully created various policies to do so. Through the National Oceanic and Atmospheric Administration's authority under the Land Remote Sensing Policy Act, the US can restrict sensing and recording of resolution of 0.5 meter or better, and prohibit distributing/circulating any images for the first 24 hours. In 1994, Presidential Decision Directive 23 ordered a 'Shutter Control' policy that details heightened level of restriction from sensing to commercializing such sensitive data. The Directive 23 was even more strengthened in 2003 when the Congress passed US Commercial Remote Sensing Policy. These policies allow Secretary of Defense and Secretary of State to set up guidelines in authorizing land remote sensing, and to limit sensing and distributing satellite images in the name of the national security - US government can use the civilian remote sensing systems when needed for the national security purpose. The fact that the world's leading aerospace technology country acknowledged the magnitude of land remote sensing in the context of national security, and it has made and is making much effort to create necessary legislative measures to control the powerful technology gives much suggestions to our divided Korean peninsula. We, too, must continue working on the Korea National Space Development Act and laws to develop the necessary policies to ensure not only the development of space industry, but also to ensure the national security.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.21-36
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• 2019

Dead fuel moisture content is a key variable in fire danger rating as it affects fire ignition and behavior. This study evaluates simple regression models estimating the moisture content of standardized 10-h fuel stick (10-h FMC) at three sites with different characteristics(urban and outside/inside the forest). Equilibrium moisture content (EMC) was used as an independent variable, and in-situ measured 10-h FMC was used as a dependent variable and validation data. 10-h FMC spatial distribution maps were created for dates with the most frequent fire occurrence during 2013-2018. Also, 10-h FMC values of the dates were analyzed to investigate under which 10-h FMC condition forest fire is likely to occur. As the results, fitted equations could explain considerable part of the variance in 10-h FMC (62~78%). Compared to the validation data, the models performed well with R2 ranged from 0.53 to 0.68, root mean squared error (RMSE) ranged from 2.52% to 3.43%, and bias ranged from -0.41% to 1.10%. When the 10-h FMC model fitted for one site was applied to the other sites, $R^2$ was maintained as the same while RMSE and bias increased up to 5.13% and 3.68%, respectively. The major deficiency of the 10-h FMC model was that it poorly caught the difference in the drying process after rainfall between 10-h FMC and EMC. From the analysis of 10-h FMC during the dates fire occurred, more than 70% of the fires occurred under a 10-h FMC condition of less than 10.5%. Overall, the present study suggested a simple model estimating 10-h FMC with acceptable performance. Applying the 10-h FMC model to the automatic mountain weather observation system was successfully tested to produce a national-scale 10-h FMC spatial distribution map. This data will be fundamental information for forest fire research, and will support the policy maker.