• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.379-379
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• 2015

최근 몇 년간 기록적인 집중호우와 태풍으로 인해 홍수피해가 점점 증가하고 있다. 국내 대부분의 하천은 고수부지 또는 제방으로 정비되어있다. 국지적으로 발생되는 집중호우는 수위를 급격하게 증가시켜 하천의 고수부지 또는 제방범람을 야기한다. 집중호우로 인한 흐름이 고수부지 또는 제방을 지나면 흐름양상은 매우 복잡하게 변화한다. 그러나 급격히 증가하는 흐름에 의해 하천의 제방, 옹벽 또는 계단지형으로 형성된 고수부지 등을 지나는 흐름특성을 분석하는 것은 매우 어렵고 이러한 불연속 단면을 고려하여 예측하기는 불가능하다. 이와 같이 급변하는 흐름이 계단형 구조물을 지날 때 잠김/드러남 특성을 조사하기위해 수리 실험을 실시하였다. 수리실험은 길이 6 m, 폭 0.4 m로 제작된 직선수로에서 수행되었다. 급격히 증가하는 댐 붕괴 흐름을 재현하기위해 수로중간에 게이트를 설치하고 상류에 물을 채운 후 빠른 속도로 게이트를 개방하였다. 하류에는 수로를 따라 계단형 구조물을 설치하고 하류경계는 물이 빠져나갈 수 있게 하였다. 하류 초기수위는 첫 번째 계단보다 약간 낮게 설정하였다. 계단형 구조물과 그 주변에 파고계를 설치하여 시간에 따른 수위변화를 측정하였다. 다양한 수리조건을 적용하여 수리실험을 수행하였고 측정된 데이터를 이용하여 급변한 비정상흐름이 계단형 구조물을 지날 때 잠김/드러남 특성을 분석하였다. 차후 이 실험 결과는 하천의 제방 및 계단지형을 고려할 수 있는 고정확도 수치모형을 개발하는 검증자료로 유용하게 사용될 수 있을 것이다.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.225-233
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• 2007

The engineering properties of surface soils in natural terrain are changed due to wildfire. This change of engineering properties induced by wildfire is related to landslides occurrence. To investigate the change of soil properties caused by wildfire, the various soil tests are performed. The soil samples are obtained from the recently burned slopes of Yangyang area, Kangwon Province. The soil samples obtained from the burned slopes are classified into three types depending on the burning grade: the perfect burning grade, the intermediate burning grade, the non-burning grade. As the result of tests, the specific gravity and the dry unit weight of soils obtained from perfect and alternative burning grades are less than those of soils obtained from non-burning grade. It judges that an electronic force, ionic components and of soils are changed and organic matters in soils are burned by wildfire. The permeability of soil obtained from alternative burning grade is the lowest and that of soil obtained from perfect burning grade is the highest. The water-repellent layer is formed on soil surface by wildfire. The water-repellent layer is existed at the area of alternative turning grade, while the layer is not existed at the area of perfect burning grade. The water-repellent layer is collapsed in high temperature more than about $400^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.274-282
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• 2013

This study was carried out to find out the physicochemical properties of rice grains of 8 varieties having various amylose content. Amylose contents of 8 varieties were ranged from 6.3 to 30.9% and could be classified into 4 groups, such as waxy, low-amylose, nonglutinous, and high-amylose. Protein contents were ranged from 5.8% to 7.5% varied depending on variety, but there was no significant difference in protein contents among groups. The hardness of milled rice grains in low-amylose and non-glutinous was stronger than waxy and low-amylose group. Whiteness of waxy group grains was the highest while non-glutinous group was the lowest. The alkaline digestive values were evenly distributed from 5.2 to 6.9 and highly correlated with amylose content. There was significant difference in pasting properties of rice flours among groups. High-amylose group showed the highest initial pasting temperature and total setback viscosity, and the lowest peaks for trough and breakdown viscosity. Low-amylose group showed the highest breakdown viscosity but the lowest setback viscosity as well as high peak viscosity. Although amylose content was significantly correlated with alkali spreading value in milled rice, initial pasting temperature, and total setback, but it was negatively correlated with toyo-meter value and setback viscosity.

• Industry Promotion Research
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• v.6 no.4
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• pp.39-45
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• 2021

This study presented the role of the counselor's transitional object through literature research, focusing on Winnicott's theory. In the process of development, infants experience anxiety when they move from absolute dependence to relative dependence with their mother. In this way, the counselor's role as an transitional object buffers separation anxiety and depressive anxiety about the loss experience, and mediates from the omnipotent fantasy to the real world. transitional objects are new objects and have a function of contributing to adaptation in reality. And it leads to the stage of separation and individualization through transitional object and transitional phenomena. It can be said that he acquires a sense of the real other that exists in order to create and destroy omnipotent, and to adapt to reality. A good enough mother makes the child's omnipotence meaningful. In this case, the true self helps the infant's weak self to grow and lead him to live his own life. When the mother fails to satisfy the infant's needs, her fantasies and spontaneous impulses are lacking. In other words, when the mother fails to reflect the infant's needs, the infant looks at her mother's mood, giving up her true self and creating a false self. The pathology of the absolute dependence phase is caused by the failure of a good enough mother's empathy and nurturing environment. At this time, the child experiences the collapse of the omnipotence illusion and experiences annihilation anxiety. Therefore, effective counseling can be carried out when providing a comfortable and stable environment by reducing separation anxiety and depressive anxiety of clients through the role of the counselor's transitional object in the counseling field.

• Journal of the Korean Geotechnical Society
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• v.27 no.2
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• pp.27-34
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• 2011

This study analyzes the determination of slope failure model due to changes in ground condition followed by heavy rainfall. With a simulated rainfall system, the movement of a slope from the rainfall penetrating the unsaturated soil is investigated with respect to various conditions of pore-water pressure, earth pressure, and moisture content, considering rainfall duration and permeability. As a result of the experiment, under the persistent precipitation of 50mm/h, pore-water pressure of weathered granite soil started increasing from the upper position of the slope, and then the pressure increased in middle and bottom portion of it in timely manner. In case of the pore-water pressure of the standard soil, the pressure increased from the middle and bottom portion, and the cause of the different order is suspected to be the difference in permeability between the standard soil and the weathered granite soil. As an outcome, though the result may vary by each foundation, there exists a danger of slope failure not only when the cumulative rainfall is more than 120 mm but also when the saturation level amounts to 60~75%.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.167-172
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• 2010

CANDU spent fuel is to be disposed of at repository finally rather than recycled because of its low fissile nuclide concentration. But the difficult situation of finding a repository site can not help introducing a interim storage in the short term. It is required to find an optimum timing of geological disposal of CANDU spent fuels related to the interim storage operation period. The major factors for determining the disposal starting time are considered as safety, economics, and public acceptance. Safety factor is compared in terms of the decay heat and non-proliferation. Economics factor is compared from the point of the operation cost, and public acceptance factor is reviewed from the point of retrievability and inter-generation ethics. This paper recommended the best solution for the disposal starting time by analyzing the above factors. It is concluded that the optimum timing for the CANDU spent fuel disposal is around 2041 and that the sooner disposal time, the better from the point of technical and safety aspects.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.256-270
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• 2020

The collapse of the medical and healthcare system in the pandemic is resulting in the voluntary participation of civil society and a new way of responding. Some of new countermeasure can be immediately utilized at the forefront of the health crisis. Appropriate technology is no longer an intermediate technology, demonstrating its role as a technology capable of overcoming the crisis of not only developing countries but also any countries where the health system has collapsed. In this Part 2, examples of health fields such medical devices as negative pressure chambers and ventilators, diagnostic chips, and diagnostic techniques, are being discussed as a quick response to the collapse of health systems under COVID-19, within the framework of appropriate technologies. Finally, the important role of scientists and engineers is discussed for the prevention of severe impacts on the vulnerable people in terms of socioeconomic status.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.427-434
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• 2019

The role of hydrophobic residues on protein folding reaction was studied by folding kinetics measurements in conjunction with protein engineering. The HubWA, which was derived from human ubiquitin by mutating the residues at 45 (Phe to Trp) and 26 (Val to Ala), was used as a mutational background. Fourteen hydrophobic residues were mutated to alanine. Among fourteen variants generated, only four variant proteins (V5A, I13A, V17A, and I36A) were suitable for folding study. The folding kinetics of these variants was measured by stopped-flow fluorescence spectroscopy. The folding kinetics of HubWA and V17A was observed to follow a three-state on-pathway mechanism. On the other hand, folding kinetics of V5A, I13A, and I36A was observed to follow a two-state mechanism. Based on these observations, transition of protein folding reaction from collision-diffusion mechanism to nucleation-condensation mechanism was discussed.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.277-277
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• 2022

급경사 산지하천은 호우 시 퇴적 하상이 붕괴하여 하천 유사량을 급격히 증가시키는 계곡형 토석류가 발생하고 도로와 교량에 피해를 일으키기도 한다. 이러한 하천재해를 저감하기 위하여 돌망태 낙차공을 설치하여 하상 안정을 강화하고 급경사에 따른 유수에너지를 줄일 수 있다. 급경사 하상에 설치한 돌망태 낙차공은 하류부 하상의 국부세굴에 따른 파괴위험이 완경사 하상의 경우에 비하여 높으므로 이를 줄이기 위한 연구가 필요하다. 이 연구에서는 광폭경사조절 개수로에 돌망태 낙차공을 설치하고 낙차공의 채움재가 복류의 특성에 미치는 영향을 파악하기 위하여 수리실험을 하였다. 수리실험에서는 최대 20º까지 경사를 조절할 수 있는 길이 1.44m, 폭 0.14m인 직사각형 단면 개수로에 SUS304 구슬을 사용하여 하상과 돌망태 낙차공을 설치하고 실험하였다. 구슬은 크기에 따라 작은구슬(10.31mm), 중간구슬(15.08mm), 큰구슬(20.63mm)을 사용하고, 하상에는 작은구슬을 깔았다. 낙차공의 크기는 길이 16cm이고 폭과 높이는 12cm이며, 돌망태는 작은구슬을 사용한 단일돌망태와 구슬 크기를 달리한 계층돌망태로 구분하였다. 계층돌망태의 상층은 작은구슬, 중층은 중간구슬, 하층은 큰구슬이 채움재로 사용되었다. 단일돌망태의 공극율은 0.399이고 계층돌망태의 공극률은 상층 0.393, 중층 0.517, 하층 0.54이다. 실험유량의 변화는 낙차공 하단부에서 표면류가 발생하지 않는 범위로 한정하였다. 낙차공 하단에서 상류 68cm 지점의 소류력과 낙차공 내부 복류의 수면경사를 측정하였다. 그 결과 단일돌망태보다 계층돌망태가 소류력과 수면경사가 더 작은 것으로 나타났으며 돌망태의 공극을 통한 통수능 차이 때문인 것으로 판단된다.

• Food Science and Preservation
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• v.14 no.3
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• pp.288-293
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• 2007

Intermediate moisture-apple snail products were prepared by adding glycerol, sorbitol, kiwi, or pineapple(2% or 5% w/w), as tenderizers, and by drying at $4^{\circ}C$ for 24 hr. The effects of the tenderizers on textural and sensory properties of the apple snail products at intermediate moisture levels were investigated. Moisture content and water activity of the products were ranged from 26.25 to 34.48% and from 0.83 to 0.87, respectively. The addition of glycerol significantly lowered water activity of apple snail samples compared to control prepared without tenderizers. On the other hand, significant increases in moisture content and water activity were observed in apple snail samples treated with kiwi or pineapple(p<0.05). All apple snail samples treated with tenderizers showed a lower shear force than did the control. Apple snail samples treated with 5%(v/v) glycerol showed a higher equilibrium moisture content than did the other samples. SDS-PAGE indicated that proteolytic enzymes in kiwi and pineapple clearly changed the structure of the myosin heavy chain and actin filaments of myofibrillar protein in apple snail samples. Intermediate moisture apple snail samples treated with tenderizers showed significantly improved overall sensory characteristics. The highest overall acceptability was obtained from apple snail samples treated with 5% pineapple, while the lowest overall acceptability was noted in the control sample. This study demonstrates that an acceptable apple snail, with intermediate moisture content, may be produced by using tenderizers at appropriate concentrations.