• Title/Summary/Keyword: Steep area

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Detailed Bathymetry and Seabed Characteristics of Wangdol-cho, Hupo Bank in the East Sea (동해 후포퇴 왕돌초 주변의 정밀해저지형 및 해저면 특성 분석)

  • Kim, Chang Hwan;Park, Chan Hong
    • Economic and Environmental Geology
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    • v.47 no.5
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    • pp.533-540
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    • 2014
  • The Wangdol-cho area, in the Hupo Bank, plays a very important role in main fishing grounds, leisure tourism and marine environmental researches of the East Sea. We analyzed the detailed bathymetry and classified the seabed characteristics of the Wangdol-cho area, based on seafloor backscattering images and sediment grain size. The Hupo Bank is developed in parallel with the eastern coastal line of Korean peninsula, and the shallowest area (Wangdol-cho) of the Hupo Bank is located along the eastern part of Hupo Port. The Wangdol-cho comprises three summits; north summit, middle summit, and south summit. The middle summit area among the three summits has the most shallow water depth with minimum about 6 m. The north summit shows about 8 m minimum depth and the south summit about 9 m. The bathymetry data around three summits represent undulating seabeds with many scattered underwater reefs and shallow water depth. The area between the underwater reefs, the flat seafloor in the northeastern part of the survey site, and the western steep slope area have relatively coarse sediments such as sandy gravel and gravelly sand. The bathymetry in the western side of the Wangdol-cho shows steep slope seabed, extending to the Hupo Basin. Fine sediments including mud and silty sand occur in the Hupo Basin area of the survey site. The submarine detailed topography and the analysis of the seafloor characteristics of the survey area are expected to contribute to management for marine environmental researches and sustainable use of ecosystems in the Wangdol-cho.

Evaluation of Flooding Characteristics of Dam Reservoir using Cumulative Flooding Area Curve (누가침수면적곡선을 이용한 댐 저수구역의 침수특성 평가)

  • Munseok Lee;Chulsang Yoo
    • Journal of Wetlands Research
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    • v.25 no.1
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    • pp.14-25
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    • 2023
  • Floodplain in a reservoir is defined as the area naturally formed between the design flood level and the normal pool level. Located around the dam reservoir, floodplain has been damaged in many different ways including cultivation. As it is impossible to restore all the damaged floodplain at once, it is necessary to determine their order of priority. This process considers various factors, among which the flooding frequency is an important hydrologic characteristic, Different from the floodplains in a river, all the floodplains around the given dam reservoir have the same flooding frequency. To overcome this problem, this study proposes to use the cumulative flooding area curve, which represents the cumulative flooding area corresponding to the reservoir water level. Especially, this study evaluates the flooding frequency of those water levels corresponding to the cumulative flooding area of 30%, 50% and 70%. As application examples, this study considers the five restoration candidates each selected in the Andong Dam, Imha Dam, Youngju Dam and Nam river Dam of the Nakdong River Basin. As a result, the cumulative flooding area curve was found to well represent the overall shape of the floodplain (i.e., steep-to-mild slope or mild-to-steep slope). Also, the flooding frequency of those water levels corresponding to the cumulative flooding area of 30%, 50% and 70% was found to be so effective to quantify the hydrologic characteristics of a floodplain.

A Study on the Runoff Characteristics m Kangwon Watershed (So-yang River Watershed) (강원도 유역의 유출 특성에 관한 연구 (소양강댐 유역 중심으로))

  • Choi, Han-Kyu;Beak, Hyo-Sun;Lee, Min-Seop
    • Journal of Industrial Technology
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    • v.21 no.B
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    • pp.223-232
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    • 2001
  • This study is finding the most appropriate model of kangwondo watershed. To synthesize each hydrograph, It is found to several parameters which are used in existing hydrographes. then the synthestic hydrograph is compared and investigated with many hydrographes of the rivers in kanwondo. These methods, Nakayasu, Clark, SCS are used to calculate the run-off of this watershed. When the calculated run-off is compared with real rating-curves, then it is found that the SCS method using the Clark's concentrantion time is the best way on this area having large watershed, long river length and gentle water slope, the Nakayasu method is more suitable on this area having small watershed, short river length and steep water slope. Also it is founded from analyzing run-off hydrographes, peak run-off and peak time that the Clark's method applied Kirpich's concentration time way is suitable in the area of kangwondo.

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Study on Risk Analysis of Debris Flow Occurrence Basin Using GIS (GIS를 이용한 토석류 발생유역 위험성분석에 관한 연구)

  • Jun, Kye-Won;Oh, Chae-Yeon
    • Journal of the Korean Society of Safety
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    • v.26 no.2
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    • pp.83-88
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    • 2011
  • Annually, many parts of the Korea have been damaged from the localized heavy rain and/or typhoons which peak between June and September, which result in extensive financial and human loss. Especially, because the most area of Gangwon province is composed of the steep slope mountains, the damages by the debris flow or land-sliding are more frequent and the frequency has been increased. To analyze the characteristics and causes of these debris flow disasters, lots of study are recently being conducted through database of weather, hydrologic, soil etc using a GIS or remote sensing. In this study, we applied GIS method to analyze the risk of the debris flow area. With the statistical analysis and infinite slope stability model(SINMAP), the debris flow risk level of the mountain slope was generated. As a result, the GIS statistical analysis showed high correlation that former model of SINMAP in determining the debris flow risk area.

Terrain Analysis of Odaesan National Park using Digital Elevation Model (수치고도모델을 이용한 오대산 국립공원지역의 지형분석)

  • 김철민;이준우;권태호
    • Korean Journal of Environment and Ecology
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    • v.9 no.1
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    • pp.70-76
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    • 1995
  • Digital elevation model for analysing terrain of Odaesan National Park was constructed by 1:50.000 topographical map. The fifty five percent of total area is located in higher than 900m in elevation, while ninty percent of the conservation area in Pirobong is above 1,100m. In other word, seventy percent of Odaesan National Park area has the slope of more than 20$^{\circ}$and is steep mountain. The aspect of the mountain mainly turned out to be eastward and westward.

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A Study on the Improvement of the Train Operation Speed for the New Metropolitan Railway (신설 광역철도 운전속도 향상방안 연구)

  • Gu, Bon-Roe;Jang, Seong-Yong
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.1-9
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    • 2008
  • A wide metropolitan railway and a metropolitan railway in metropolitan area are transportation systems to cope with possible large demand and are under construction continually. A wide metropolitan railway and a metropolitan railway in metropolitan area are running with low speed because it is difficult to improve train speed according to short distances between stations and topography. There is a few study on improving commercial speed on the existing wide metropolitan railway and metropolitan railway in metropolitan area, but there is no study on a new wide metropolitan railway. This study present speed-up scheme of the Sosa-Wonsi line by enlarging the curve radius, reducing the horizontal steep gradient, reducing the stopping time, speeding up at underground section, and installing the PSD, etc. This scheme is evaluated using the simulation technique.

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Reuse of Vacant Houses in the Old Settlements of Urban Area - Focused on the Andeokbeol in Cheongju City, Korea - (도심 옛 마을 내 빈집활용의 방향성 도출에 관한 연구 - 청주시 안덕벌 일원을 중심으로 -)

  • Cho, Sang-Min;Kim, Tai-Young
    • Journal of the Korean Institute of Rural Architecture
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    • v.21 no.1
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    • pp.17-24
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    • 2019
  • This study is to seek for the reuse of vacant houses in the old settlement of urban area, focused on the Andeokbeol in Cheongju city, Korea. The following results were derived. Firstly, the maintenance and reuse methods of vacant houses are made for a number of house type as well as a variety of locational characteristics(flatland, gentle and steep slope) of the Andeokbeol. Secondly, reuse plans of vacant houses are established for a variety of classes such as local residents, artist and youth activist around cultural complex(Cheongju old cigarette factory), and outsiders. Thirdly, owners, users and intermediaries of vacant houses should find a solution to the reuse of them in company with Andeokbeol residents. And also institutional and administrative support measures are established for reuse of vacant houses.

Landslide prediction system by wireless sensor network (무선센서 네트워크를 이용한 산사태 모니터링 기초기술 연구)

  • Kim, Hyung-Woo
    • 한국정보통신설비학회:학술대회논문집
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    • 2007.08a
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    • pp.191-195
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    • 2007
  • Recently, landslides frequently happen at a natural slope during period of intensive rainfall. With rapidly increasing population of steep terrain in Korea, landslides have become one of the most significant natural hazards. Thus, it is necessary to protect people from landslides and to minimize the damage of houses, roads and other facilities. To accomplish this goal, many landslide prediction methods have been developed in the world. In this study, a simple landslide prediction system that enables people to escape the endangered area is developed. The system is focused to debris flows which happen frequently during periods of intensive rainfall at steep slopes in Kangwondo. This system is based on the wireless sensor network that is composed of sensor nodes, gateway, and server system. Sensor nodes that are composed of sensing part and communication part are newly developed to detect sensitive ground movement. Sensing part is designed to measure tilt angle and acceleration accurately, and communication part is deployed with Bluetooth (IEEE 802.15. I) module to transmit the data to the gateway. To verify the feasibility of this landslide prediction system, a series of laboratory tests is performed at a small-scale earth slope supplying rainfall by artificial rainfall dropping device. It is found that sensing nodes installed at slope can detect the ground motion when the slope failure starts. It is expected that the landslide prediction system by wireless senor network can provide early warnings when landslides such as debris flow occurs, and can be applied to ubiquitous computing city (U-City) that is characterized by disaster free.

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Geophysical and Sedimentological Characteristics of Lomilik Seamount, West Pacific (서태평양 Lomilik 해저산 퇴적환경 특성)

  • Lee, Hyun-Bok;Oh, Jae-Kyung;Park, Cheong-Kee;Chi, Sang-Bum;Kim, Jong-Uk;Moon, Jai-Woon;Nam, Sang-Heon
    • Ocean and Polar Research
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    • v.26 no.2
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    • pp.207-218
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    • 2004
  • Lomilik Seamount in the west Pacific was seismically surveyed and photographed to illuminate the bottom topography, the condition of manganese crust, and the characteristics of sedimentary environment. Lomilik Seamount has a NW-SE elongated bottom topography with steep slopes in the NESW direction part. Even though the steep slopes of the seamount are devoid of deposits, the summit area and gentle slope of the seamount are covered with thick deposits. The seismic data indicate that Lomilik Seamount is a flat-topped and step-faulted guyot of volcanic origin. Deep-sea camera photographs show that much of the seafloor is rippled in symmetrical and asymmetrical patterns. The traces of biological activity were distinct on gentle seafloor suggesting the low-energy bottom conditions. Some photographs also show outcrops encrusted with manganese crusts. Sedimentary environments in the Lomilik Seamount appear have been governed by regional morphology and strong bottom current.

Improved Plan for Evacuation of Residents in Landslide-Prone Rural Area (산사태 대비 농촌 주민 대피계획 개선 방안)

  • Kim, Jungmeyon;Park, Sungyong;Lim, Changsu;Yeon, Kyuseok;Kim, Yongseong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.59 no.1
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    • pp.1-10
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    • 2017
  • This study has purpose on deducting problems of evacuation plan for vulnerable populations in disaster and suggesting improvement plan through analysis of disaster weakness in domestic rural region aiming at vulnerable populations in disaster like old people containing most of domestic rural population, sometimes being in blind spot of safety when landslide or disaster occur. As a result, we could know that rural regions have high proportion of vulnerable populations in disaster like old people, also being so weak to landslide and slope collapse. So we suggested development of manual describing prevention of disaster and evacuation for vulnerable populations in disaster like old people and disaster evacuation organization for house and minimizing solution for damage of human life through improvement of steep slope evaluation criteria.