• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.162-165
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• 2015

본 연구는 ${\bigcirc}{\bigcirc}$ 공구 공유수면 매립공사 수행 중에 매립토량의 부족이 발생함에 따라 이를 대상으로 원인을 분석하고자 수행하였다. 매립지의 토량부족 원인을 파악하기 위해 설계 및 계측자료를 수집하여 시공 현황을 파악하고 지반조사를 통해 해안지역과 매립지반의 시료를 채취하여 성상분석과 원지반에 대한 공학적 특성을 비교 검토하였다. 특히. 현장 시추조사에 의한 경계면 분석과 토질 종류를 점성토, 사질토, 부유토로 구분하고 침하량 공식에 따라 발생량을 산출하였다. 구역의 구분은 설계 시와 동일한 조건에서 침하량을 계산하였고 설계 시 지반고가 침식과 퇴적으로 인해 일부 변경되어 설계시 지반고와 착공시 지반고를 구분하여 기재하고 각각의 침하량을 비교하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.1
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• pp.189-196
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• 1991

The objective of this study was to investigate the effect of temperature on microbial characteristics and treatment efficiency in aerated submerged biofilm process. From the results of the research, conclusions were derived as following: 1. Biofilm density, attached biomass and biofilm thickness were $30-42mg/cm^3$, $1.2-2.7mg/cm^2$ and $380-690{\mu}m$, respectively. These were greatly affected by the variation of temperature ($5-20^{\circ}C$) and packing ratio(45-90%). 2. The ratio of suspended biomass to the total biomass in the reactor was in the range of 10 to 50 % in accordance with the variation of temperature and packing ratio. Therefore, the portion of suspended biomass cannot be neglected. 3. BOD removal efficiency increased as either temperature or biomass(suspended and attached) concentration increased. 4. The aerated submerged biofilm process appeared to be less affected by temperature variation and the estimated temperature correction coefficient of the Van't Hoff-Arrhenenius equation was 1.042.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.1
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• pp.79-92
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• 1984

The analysis of total load was carried out by using the theory of unit stseam power (USP). The dimensionless USP equation of $S_R$ which was the rate of suspended load and bed load was derived from the USP function by applying the Einstein's reference concentration and Stokes' fall velocity. And the R relationship between the water discharge and Reynolds number (Re) was discussed, and it was shown that USP was closely related with Re. The value of $S_R$ was determined from the experimental data of Han River downstream and Mantz. And it was tested to several observatories of Korean Rivers. A good correlation among USP, suspended load and $S_R$ was shown and USP was increased with the increment of the turbulent intensity. Judging from the above results, it is considered this study can be contributed to estimate the total load.

• Journal of Ocean Engineering and Technology
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• v.26 no.4
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• pp.50-56
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• 2012

When a liquid cargo tank is partially filled with fluid, internal impact loads can be occurred from the vessel's motions. In this study, liquid sloshing problems with a thin top layer of particles with a lighter density than water and the coupling effects of the liquid-sloshing/vessel-motion were investigated in order to reduce the sloshing-induced impact loads. The PNU-MPS (Pusan-National-University-modified Moving Particle Simulation) method for solving the liquid motion inside a tank and the CHARM3D BEM (Boundary Element Method) based time-domain ship motion analysis program for vessel-motion simulation were coupled. From the simulation results, we could see that the floaters seemed to be quite effective at reducing the sloshing impact loads in the case of tank-only sloshing problems, but not as much for the coupling problem with vessel motion.

• Korean Journal of Organic Agriculture
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• v.18 no.3
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• pp.377-386
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• 2010

Sweet persimmon, 'Fuyu', is the major cultivar for MA storage, but browning of blossom end part and fruit surface darkening occur during storage and decrease fruit qualities in fresh fruit market. Calcium (Ca) has a very important role in cell membrane and reduces Ca-related fruit disorder. Therefore, this study was conducted to investigate the effect of soluble Ca fertigation and foliar applications on soil chemical properties, root activity, and leaf nutrient status. Ca concentration in the soil was higher in both Ca fertigation (Ca-FG) and Ca+IBA fertigation (Ca+IBA) treatments than the other treatments, such as control (Cont), Ca foliar application (Ca-FA), and IBA fertigation (IBA). The increase in soil Ca improved soil pH. The Ca+IBA treatment increased root activity. Leaf Ca concentration was significantly increased by the CA-F A application, followed by Ca+IBA, and Ca-FG treatments.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.138-138
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• 2011

식생된 개수로에서 식생의 영향을 파악하기 위해 k-$\in$ 난류 모형을 이용하여 수치모의를 하였다. 식생의 영향을 고려하기 위해 항력항을 추가한 지배방정식을 구성하였으며, 지배방정식을 해석하기 위하여 유한체적법을 사용하였다. 수치모의에서 구한 식생된 개수로의 흐름구조를 기존의 수리실험 결과와 비교하여 비교적 잘 일치함을 확인할 수 있다. 난류의 생성과 소멸을 수치모의한 결과, 부분구간 식생된 경우 식생높이 보다 낮은 구간에서는 후류에 의한 난류 생성이 지배적이며, 식생높이보다 높은 구간에서는 주로 마찰에 의한 난류 생성이 지배적임을 보였다. 기존의 연구들은 식생의 영향을 고려하여 개수로의 흐름을 연구한 예는 드물며, 현재까지 진행되어진 국내의 연구는 난류모형을 이용하여 식생된 개수로에서의 흐름 구조를 모의하였다. 따라서 난류흐름을 모의하는데 가장 보편적인 k-$\in$ 난류모형을 이용하여 식생된 개수로에서 수직방향으로의 흐름구조와 식생의 영향을 해석하는 것은 그 자체로도 의미 있는 연구이며, 앞으로의 환경수리 문제를 해결하기 위해 선행되어야 하는 연구이다. 식생된 개수로에서의 난류구조와 부유사 이동에 대한 식생의 영향을 비정상 1차원 수직모형으로 해석하였으며, 폐합문제를 위해 2-방정식인 k-$\in$ 난류모형을 사용하였다. k-$\in$ 난류모형에 식생에 의한 항력항을 더하여 지배방정식을 구성하였다. 수직방향에 대해 흐름방향 유속 u, 난류에너지 k, 그리고 난류에너지 소산율 $\in$의 분포를 구하고, 부유사에 대한 수송방정식을 풀었다. 식생된 개수로와 식생되지 않은 개수로에서의 유속분포, 난류강도, 레이놀즈 응력 분포와 난류의 생성과 소멸을 구하여 식생이 난류흐름에 미치는 영향을 분석하였다.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.92-94
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• 2003

The standard cultured sheet grafts for large full-thickness burn wound has been tempered by weak points such as long culture periods, difficulty in handling the fragile sheets, high costs and the detachment of the skin cells from the culture dishes by enzymatic digestion. Here we report on a new technique of using skin cells cultured on spherical microcarriers for skin regeneration. We cultured the human skin cells on biodegradable polymer microcarriers and transplanted onto wounds in the back of nude mice. After 21 days, histological examination showed the regeneration of epithelium. The technique developed in this study overcomes the drawbacks of the current artificial skin grafts, and could be utilized as an efficient skin wound regeneration therapy.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.135-142
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• 2000

The purpose of this study was to investigate the effects of onion and garlic juice on the lipid oxidation of fish oil as antioxidants and quality characteristics of fish muscle. The samples were treated with onion and garlic juice at 5%(w/w) or 10%(w/w) of fish muscle, and stored at 4$\pm$1$\^{C}$ and -18$\pm$2$\^{C}$ for 7 and 42 days, respectively. The results of this study were as follows: Lipid oxidation in samples was measured by AV, POV and TBA value. AV and TBA values of the samples treated with 5% onion and garlic juice were lower than those treated with l0% onion and garlic juice. POV of the samples treated with onion were lower than those treated with garlic juice. Lightness and yellowness of the sample were the highest in 10% onion and garlic juice-treated ones. The score of overall quality in sensory evaluation was the highest in the samples treated with onion juice stored at 4$\pm$1$\^{C}$.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.78-82
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• 1978

In a series of studies on the utilization of persimmons, the purpose of this experiment was to examine the optimum thickness of film using different number of persimmons per film bag. 'Fuyu', persimmon variety was used in this investigation. The results obtained were as follows: The optimum thickness of the film bag was 0.08mm, 0.06mm, and 0.04mm for the bags packed with 3, 10 and 50 persimnons, respectively. The changes in the ratio of firmness, loss of fresh weight, titrable acidity and percentage of sugar contents were minimal in these three optimum combinations than the others. These results could be explained by the balanced optimum gas concentration, $CO_2$ 5-10% and $O_2$ 5%, in those three optimum combination. Therefore, it was suggested that the different thickness of film bag needs a particular number of fruits packed per bag for the long term storage in persimmons.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.3
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• pp.165-174
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• 2015

Non-point source pollution associated with suspended solids in stormwater has been known to often adversely affect surface water ecosystems. Various methods of treating stormwater in the basin area before the stormwater reaches the receiving body of water have been developed. However, these treatment methods tend to be costly to install and also to maintain. In this study, an economical way of removing TSS (total suspended solids) from stormwater runoff with a fabric filter system was developed. Polyester was chosen as a fabric-filter material, because it was found to be economical in cost and relatively resistant to various chemicals. An experimental device was developed and used to determine filtration rates through polyester fabric samples of a series of several pore-opening sizes ($20{\mu}m$ to $94{\mu}m$) under a series of water-heads (0.25 to 1 m). It was found that the filtration rate increased as the size of water head increased. It was also found that the smaller the pore size of the fiber filter was, the higher the TSS removal efficiency was. However, the TSS removal efficiency was not found to be much different among the filters with different sizes of pore opening due to the fact that most mass of TSS was associated with large particles.