• Journal of the Korean Geographical Society
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• v.48 no.5
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• pp.615-628
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• 2013

The waterfall can be formed by difference between the height of up and down part in new channel, is formed by channel avulsion that rapidly changing of river channel course. This study described types and processes of waterfalls by channel avulsion, and analyzed rates and factors of waterfall recession, on object to 7 waterfalls in South Korea. Bulyeong falls at Uljin-gun, Yongchu falls at Yeongdeok-gun, Jikyeon falls at Yanggu-gun and Gwangpum falls at Uljin-gun are formed by natural incised meander cutoff. Samhyeongje falls at Taebaek-si and Guryong falls are formed by river capture processes, and Palbong falls at Chungju-si is formed by artificial channel cutting for farm land secured. The locations of waterfalls gradually moved to upstream over time by head erosion. The recession rates were measured by 3~4m/ka on Bulyeong falls, Yongchu falls, Jikyeon falls and Samhyeongje falls, to estimate of formation age. Recession rates of these 4 waterfalls were analyzed that have clearly positive correlations with drainage area, precipitation, corrosion and weathering capability of bedrock, and initial height of waterfall.

• Journal of the Korean association of regional geographers
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• v.18 no.2
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• pp.129-140
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• 2012

In order to examine geomorphic characteristics such as form and retreat process of waterfalls in Jeju Island, 26 waterfalls were classified based upon materials forming a fall face. The waterfalls could be categorized into three types such as single unit, multiple units and basal soft-rock based upon the number and type of a lava flow. A block fall, composed of a pile of large blocks, could be added to the typology of waterfalls in Jeju Island. While the single unit fall is distributed in a region of trachyte or trachyandecite, the multiple units fall and basal soft-rock fall are largely developed in a region of basalt or trachybasalt. A retreat process of the single unit fall is an inclination or a replacement, but the basal soft-rock fall shows a parallel retreat. The multiple units fall exhibits three types of a retreat process according to the physical properties of a lava flow. The fall face is generally vertical due to well-developed vertical joints of a lava flow.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.36-36
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• 2019

강원도 설악산 국립공원에는 국내 최장의 토왕성 폭포가 있다. 유역면적이 $0.54km^2$에 불과하여 평소에는 폭포의 물줄기를 볼 수 없지만, 비 온 뒤에는 며칠간 하얀 물줄기의 장관을 연출한다. 본 연구에서는 물리적 기반의 수문모형인 CAT3.0을 이용하여 강우시 토왕성 폭포의 유출량을 분석하고 강우량에 따른 유출지속기간을 산정하여 강우의 누적량 및 지속기간에 따른 폭포의 물줄기를 볼 수 있는 기간을 추정하고자 하였다. CAT 3.0은 다양한 침투방정식중에 Rainfall Excess, Horton Eq., Green-Ampt. Eq.을 이용하여 강우시 토양특성(토양깊이, 투수계수)과 잠재증발산량과 토양수분량에 의한 실제증발산량을 산정하고 유출량을 계산하는 수문모형이다. 토왕성 폭포의 유출 특성을 분석하기 위하여 속초지점의 19년간(2010~2018) 관측자료를 이용하였으며, 토양의 깊이는 10 cm, 30 cm를 가정하여 비교하였다. 유출해석을 위하여 일단위 자료를 사용하였으며, 강우지속일수 및 누가강우량에 따른 유출을 산정하고 폭포의 물줄기가 확연히 보일 수 있는 한계유출량을 추정하였다. 폭포로부터의 유출량을 측정하는 관측지점이 없으므로, 폭포의 물줄기를 볼 수 있는 기간은 방송사 뉴스, 신문기사, SNS 등의 다양한 정보원으로부터 유추해석하였다. 이러한 분석결과로부터 강우에 의한 토왕성 폭포의 물줄기를 볼 수 있는 기간을 제시하였다.

• Journal of The Geomorphological Association of Korea
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• v.21 no.4
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• pp.85-96
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• 2014

A waterfall is a channel unit with steep bedrock. No strict criteria for height, water volume, gradient to define waterfalls exist in Korea. The goal of our study is to classify waterfalls based on morphological forms which are the outcomes of developmental processes. The genesis of waterfall depends upon erosional properties of waterfall. The height, gradient, bedrock strength and stream power of waterfalls are regarded as the main factors, by which waterfalls can be classified. We find out that the most important factor for the development of waterfalls is joint system. Development of joint system varies depending on bedrocks. Flow directions and erosional types are decided by the density and direction of joint system in the bedrock, which also decide the height and gradient of stream bed. Joint type decides the gradients of the bed, gradient and height of waterfalls, therefore, decides morphological forms.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.343-347
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• 2007

Cascade Stomach is commonly found in obese patients. This study examined the physical factors, such as gender, age, height, weight and level of obesity, associated with a cascade stomach. Over a 12 month period between 2007 a series upper gastrointestinal examinations were carried out on 3,320 people, which included 564 patients with a Cascade Stomach. The results are as follows : 1. A cascade stomach was observed in 564(16.9%) out of 3,320 subjects. 2. A body mass index(BMI) > 120% was observed in 226 of the 564 cascade stomach patients. 3. Among those with a BMI > 120, 63.7% were female, 45.6% were aged between 50-59 years, 49.1% were between 151-160 cm in height and 31.0% were above 76 kg in weight. 4. The symptoms observed in the cascade stomach and obesity groups were subclinical(62.6% and 57.5%, respectively), dyspepsia(16.8% and 17.3%, respectively) and gastric soreness(10.8% and 15.0%, respectively). The incidence of a cascade stomach is higher in those with obesity. In addition, there is a higher incidence in females, those aged between 50 and 59, those between 151 and 160 cm in height and those weighing more than 76 kg. The main symptoms observed were subclinical, followed in order by dyspepsia and gastric soreness. This study showed a strong association between a cascade stomach and obesity. However, more studies will be needed to confirm this.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.65-75
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• 2015

The findings of basic study on the awareness of falls in terms of Gwanpokdo(Paintings of Viewing Falls) were drawn as follows. First, there is a difference in an esthetic sense that water brings depending on the ratio of falls, and Gwanpokdo(Fall Landscape) in which falls take up more than 20% of the canvas focuses more on falls so that it brings about the awareness of landscape through direct communication with nature. Second, the diagonal composition of the canvas has symmetry between falls and a person viewing the falls, which makes view point even clear. In addition, margins of the canvas were missing due to the effect of True-View Landscape Painting during the late Joseon Dynasty, and overall composition of using the entire canvas became popular. This overall composition is stable and disposed with lopsided composition, so this heightens sense of balance and the meaning of falls. Third, Gwanpokdo(Paintings of Viewing Falls) of Josoen Dynasty showed various types of viewing falls in distant view, but as the distance between falls and persons got closer in the latter part of Joseon Dynasty, falls were no longer utopia but it expressed a sense of beauty and aesthetic contemplation through direct communication with real nature. Fourth, Gwanpokdo(Paintings of Viewing Falls) of Joseon Dynast had many drawings of a person viewing falls and viewing behaviors such as Supyeong gyeong(level landscape), Amgang gyeong(lower landscape), Bugam Gyeong(higher landscape), and glimpse viewing. Fifth, rocks out of landscape elements make falls vivid and are so expressed as yin and yang that falls and rocks are well contrasted with each other, maximizing beautiful scenery of falls. Sixth, woody plant of Gwanpokdo(Paintings of Viewing Falls) was mostly pine trees which symbolized the literati's fidelity and integrity at that time and emphasized the firm meaning of transcending the nature, matching with symbolization of falls.

• Proceedings of the Korea Contents Association Conference
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• 2015.05a
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• pp.113-114
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• 2015

본 연구는 조선시대 관폭도를 중심으로 옛 선인들의 명승 인식 태도에 관하여 살펴보고자 하였다. 연구결과 폭포 표현은 폭포의 형상이나, 조망하는 대상에 있어서 차이가 있지만 관념 산수에서의 폭포가 지니는 의미는 변하지 않았다. 폭포는 이상향과 속세의 경계이면서 동시에 관조의 매개체가 되었고, 단순히 풍경의 의미가 아닌 관조적 대상의 장면으로 인식하는 경향이 컸다.

• Journal of the Korean Vacuum Society
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• v.16 no.4
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• pp.273-278
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• 2007

For the simulation of active region in the quantum cascade lasers (QCL), we solved Schrodinger equation utilizing Runge-Kutta method and Shotting method. Wavelength, phonon resonant energy, and dipole matrix element were simulated with the variation of active region thickness. As a result of such simulation, it was suggested the tolerance range of epi-layer thickness error when 3-quantum well QCL structures are grown.

• Air Cleaning Technology
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• v.15 no.1 s.56
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• pp.84-84
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• 2002

• 산림경영
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• s.216
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• pp.40-43
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• 2015