• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1385-1390
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• 2006

외국에서 ASM 모델의 BNR 적용 연구결과를 국내 하수에 적용하기에는 하수농도, 온도, 슬러지농도 등이 국내와는 달라 적용상 무리가 있다. 본 연구에서 BNR 시뮬레이션을 위한 입력 자료로 활용되는 인자들은 IAWPRC task group에서 제안하는 값들을 사용하되 국내 하수성상에서 필요로 하는 인자들은 직접 실험을 통하여 부분적으로 구해냄으로써 모델 시뮬레이션의 신뢰도를 높이고자 하였다. F/M비의 변화량과 1/SRT과의 관계로부터, 종속영양미생물 생산계수 $Y_H$값을 구한결과, 0.40mg VSS/mg COD였다. 이것을 ASM No.2d에 적용하기 위하여 mg cell COD formed/mg COD oxidized 단위로 환산한 결과 0.58을 나타냈다. H 하수처리장의 1차 침전지 하수를 이용하여 호기성상태에서 OUR Test를 통한 미생물에 의한 유기물 섭취시 산소섭취율 변화를 측정하였다. 호기성상태와 무산소상태에서 구한 쉽게 분해되는 용존성유기물(Ss)값을 비교해보면 각각 35.5mg/L와 39.9mg/L로 약간의 차이는 있으나 유사한 값을 보여주고 있다. 시뮬레이션을 위한 동력학적 계수 중 무산소 상태에서 종속영양미생물의 ${\mu}_{max,H}$는 $3.56d^{-1}$로 나타났고, 호기성상태에서는 구하면 ${\mu}_{max,H}$는 $4.2d^{-1}$로 산출되었다. 종속영양미생물의 사멸계수 $b_H$를 구하기 위한 실험에서 초기 OUR의 10%이내가 될 때까지 걸린 시간은 7일정도가 걸렸으며, 사멸률 $b_H$는 $0.043hr^{-1}$로 나타났다. 독립영양미생물의 최대비성장률 ${\mu}_{max,A}$는 최대암모니아 섭취률을 이용하여 구한 결과 $0.65d^{-1}$로 나타났다.EX>$60%{\sim}87%$가 수심 10m 이내에 분포하였고, 녹조강과 남조강이 우점하는 하절기에는 5m 이내에 주로 분포하였다. 취수탑 지점의 수심이 연중 $25{\sim}35m$를 유지하는 H호의 경우 간헐식 폭기장치를 가동하는 기간은 물론 그 외 기간에도 취수구의 심도를 표층 10m 이하로 유지 할 경우 전체 조류 유입량을 60% 이상 저감할 수 있을 것으로 조사되었다.심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴 분석기간의 주식가격정보에 의하여 최대한 발휘될 수 있음을 확인하였다.(M1), 무역적자의 폭, 산업의 생산

• Proceedings of the Korea Database Society Conference
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• 1999.06a
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• pp.415-421
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• 1999

Altman의 연구(1965, 1977)나 Beaver의 연구(1986)와 같은 전통적 예측모형은 분석자의 판단에 따른 예측도가 높은 재무비율을 선정하여 다변량판별분석(MDA： multiple discriminant analysis), 로지스틱회귀분석 등과 같은 통계기법을 주로 이용해 왔으나 1980년 후반부터 인공지능 기법인 귀납적 학습방법, 인공신경망모형, 유전모형 둥이 부실기업예측에 응용되기 시작했다. 최근 연구에서는 인공신경망을 활용한 변수 및 모형개발에 관한 보고가 있다. 그러나 지금까지의 연구가 주로 기업의 재무적 비율지표를 고려한 모형에 치중되었으며 정성적 자료인 비재무지표에 대한 검증과 선정이 자의적으로 이루어져온 경향이었다. 또한 너무 많은 입력변수를 사용할 경우 다중공선성 문제를 유발시킬 위험을 내포하고 있다. 본 연구에서는 부실기업예측모형을 수립하기 위하여 정량적 요인인 재무적 지표변수와 정성적요인인 비재무적 지표변수를 모두 고려하였다. 재무적 지표변수는 상관분석 및 요인분석들을 통하여 유의한 변수들을 도출하였으며 비재무적 지표변수는 조직생태학내에서의 조직군내 조직사멸과 관련된 생태적 과정에 대한 요인들 중 조직군 내적요인으로 조직의 연령, 조직의 규모, 조직의 산업밀도를 도출하여 4개의 실험집단으로 분류하여 비재무적 지표변수를 보완하였다. 인공신경망은 다층퍼셉트론(multi-layer perceptrons)과 역방향 학습(back-propagation )알고리듬으로 입력변수와 출력변수, 그리고 하나의 은닉층을 가지는 3층 퍼셉트론(three layer perceptron)을 사용하였으며 은닉충의 노드(node)수는 3개를 사용하였다. 입력변수로 안정성, 활동성, 수익성, 성장성을 나타내는 재무적 지표변수와 조직규모, 조직연령, 그 조직이 속한 산업의 밀도를 비재무적 지표변수로 산정하여 로지스틱회귀 분석과 인공신경망 기법으로 검증하였다. 로지스틱회귀분석 결과에서는 재무적 지표변수 모형의 전체적 예측적중률이 87.50%인 반면에 재무/비재무적 지표모형은 90.18%로서 비재무적 지표변수 사용에 대한 개선의 효과가 나타났다. 표본기업들을 훈련과 시험용으로 구분하여 분석한 결과는 전체적으로 재무/비재무적 지표를 고려한 인공신경망기법의 예측적중률이 높은 것으로 나타났다. 즉, 로지스틱회귀분석의 재무적 지표모형은 훈련, 시험용이 84.45%, 85.10%인 반면, 재무/비재무적 지표모형은 84.45%, 85.08%로서 거의 동일한 예측적중률을 가졌으나 인공신경망기법 분석에서는 재무적 지표모형이 92.23%, 85.10%인 반면, 재무/비재무적 지표모형에서는 91.12%, 88.06%로서 향상된 예측적 중률을 나타내었다.

• Journal of Nutrition and Health
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• v.53 no.2
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• pp.111-120
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• 2020

Purpose: Corosolic acid (CA), also known as 2α-hydroxyursolic acid, is present in numerous plants, and is reported to exhibit anti-cancer and anti-proliferative activities in various cancer cells such as osteosarcoma, hepatocellular carcinoma, lung adenocarcinoma, and colon cancer. However, the anti-cancer activity of CA on human breast cancer cells and the underlying mechanisms remain to be elucidated. The present study aimed to investigate the anticancer effects of CA in the human breast cancer cell line, MDA-MB-231. Methods: Cell viability, reactive oxygen species (ROS) production, apoptosis marker protein expression, migration, invasion rate, and vascular endothelial growth factor (VEGF) levels were assessed by treating MDA-MB-231 cells to increasing concentrations of CA. Results: The results showed that CA significantly inhibited the cell proliferation of MDA-MB-231 cells in a dose-dependent manner. To assess the effect of CA on apoptosis, nuclei of MDA-MB-231 cells were stained with DAPI solution. Chromatin condensation, which indicates apoptosis, was observed to increase dose-dependently. In addition, western-blot analysis revealed elevated levels of the apoptosis marker proteins (Bax and cleaved caspase 3) subsequent to MDA-MB-231 exposure to CA. ROS production was also increased in the CA-induced apoptosis in MDA-MB-231 treated cells. Interestingly, CA exposure resulted in significantly decreased migration and invasion rates in the MDA-MB-231 cells. Data further revealed that exposure to CA markedly decreased the VEGF concentration, thereby contributing to a reduction in angiogenesis. Conclusion: Our results determined that exposure to CA induces anti-proliferation, apoptosis, and ROS production, and suppresses cell migration and invasion rate in MDA-MB-231 cells. Taken together, these results indicate the potential of CA to be applied as an effective chemotherapeutic agent for treating breast cancer.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.3
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• pp.101-109
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• 2006

Earthworms(Eisenia fetida) were fed with paper mill sludge produced from P&G or Yuhan Kimberly paper manufacturing factory, or cow dung manure. Turnover rate of feed into earthworm biomass and excreting rate on each feed were investigated on dry weight base. Biomass of earthworm population was increased on paper mill sludge, but it was fallen to death on cow dung manure, which had high electrical conductivity and low redox potential. When P&G paper mill sludge was supplied to adult, elder juvenile or younger juvenile for 84 days, turnover rate of feed into earthworm biomass was 0.48, 0.40 and 0.76%, respectively, and on Yuhan Kimberly paper mill sludge 0.26, 0.45, 0.42%. When P&G paper mill sludge was supplied to adult, elder juvenile or younger juvenile, excreting rate was 49.02, 54.32 and 55.39%, respectively and on Yuhan Kimberly paper mill sludge 32.22, 41.86, 40.69%, and on cow dung manure, 73.73, 57.89. 76.38%.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.202-206
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• 2013

High-grade mucoepidermoid carcinomas (MECs) have difficulty in cure and 5-year survival rate is quiet low. Therefore, we need new therapeutic agents and molecular targets. Betulinic acid (BA) is one of the materials which is easily found in the world and shows tumor-suppress effects in various tumor types. In addition, many kinds of normal tissues have a resistance to BA treatment. In this study, we investigated the anti-proliferative activity of BA and its molecular targets in MC-3 human MEC cells using western blot analysis and DAPI staining. BA inhibited cell viability and induced apoptosis in MC-3 cells. It affected Specificity protein 1 (Sp1) and its downstream molecule, survivin whereas it did not affect myeloid cell leukemia-1 (Mcl-1). Therefore, we suggest that BA can be a potential anti-cancer drug candidate regulating Sp 1 and survivin to exert apoptotic cell death.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.5
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• pp.675-681
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• 2011

In this paper, we dealt with the design and fabrication of a medium pressure ultra-violet (UV) lamp and a magnetic ballast which are main components for ballast water treatment systems (BWTS). To acquire an optimal discharge condition of UV lamp, electrical and optical characteristics depending on the argon gas volume and the amount of mercury were experimentally analyzed. Rated voltage, current and power consumption of a prototype lamp were 490 [V], 8.6 [A] and 4.0 [kW], respectively. UV intensity of the lamp was 15 [%] higher than that of an equivalent lamp which is used in a BWTS. The magnetic ballast was designed in a UI core type through theoretical analysis and simulation. The open voltage and the rated power consumption of the ballast were 920 [V] and 8.5 [kVA] respectively. The disinfection efficacy which is carried out in a BWTS equipped with the UV lamp and magnetic ballast was over 99.99 [%], and this satisfy the IMO regulations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.411-419
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• 2018

This study investigated the survival rates and physiological responses of Korean rockfish, Sebastes schlegeli, in live fish containers ($8^{\circ}C$, 33 psu) for 18 days. The survival rate was 99% and 97% in the control and experimental groups, respectively. Hematocrit and hemoglobin did not differ significantly between the control and experimental groups. Glucose and cortisol rose immediately on the first day of containment, but both gradually normalized. Aspartate aminotransferase and alanine aminotransferase did not differ significantly between the two groups after recovery. $NH_3$ continued to rise after the first day, but decreased to a level not significantly different from that of the control group during the recovery period. Plasma ions and osmolality did not change abnormally. The hemocyte population was not significantly different from that of the control. The ratios of apoptotic and necrotic cells indicated no specific variation in hemocyte viability. The histological changes in the skin and gills were not significantly different from those seen in the control. The experimental data obtained in this study suggest that live fish containers may be used to transport Korean rockfish without significantly affecting their physiology or survival.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.452-457
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• 1999

Algicidal bacteria were isolated from the mud of south coastal sea of Korean peninsula and screened to evaluate algicidal activity on Cochlodinium polykrikoides. The optimum condition for the development of highest algicidal activity was determined, The optimum sodium chloride concentration for algicidal activity of isolated algicidal bacteria was $3\%$. The optimum temperature, pH and culture time for the highest algicidal activity were $30^{\circ}C$, pH 7 and above 24 hr, respectively. The algicidal activity were significantly increased at the stationary phase of the cell growth and continuously increased up to maximum at the death phase, probably due to the release of algicidal substance by cell Iysis. The effect of zinc ion addition on algicidal activity, was observed and indicated that the substance requires zinc for its activity. The candidate for the algicidal substance may be $\alpha$-mannosidase.

• Korean Journal of Organic Agriculture
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• v.30 no.3
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• pp.393-407
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• 2022

The effect of Neobacillus sp. JC05 extract on the defense response in cucumber plants against root-knot nematode (RKN) was evaluated. As a result of drench treatment of JC05-extract in cucumber plants, formation of egg mass per plants and disease severity were significantly decreased compared to untreated control plants; the malondialdehyde contents also decreased in JC05-extract treated plants. When eggs of Meloidogyne incognita were inoculated, cucumber plants treated with JC05-extract elevated pathogenesis-related gene expression such as chitinase and lipoxygenase, these are well known as inducing resistance in plants, in addition, peroxidase among antioxidant enzymes was significantly activated. Moreover, the JC05-extract enhanced FDAse activity in soils grown cucumber plants inoculated by eggs of M. incognita. Taken together, these results suggest that the JC05-extract could involve in activation of defense-related mechanisms of cucumber plants and result in decrease of disease occurrence caused by M. incognita.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.81-85
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• 2013

The stored-product insects have been a serious problem during the entire process of distribution on the food industry. Especially, the Indian meal moth (Plodia interpunctella) is one of stored-product insects which causes harm through penetrating into the food packaging. The objective of this study was to develop the anti-insect packaging material with fennel (Foeniculum vulgare) oil (FO). The FO has been selected for insecticidal substance against P. interpunctella, which was tested by fumigant toxicity assay. An anti-insect sachet was prepared by FO and filterpaper placed in a small paper bag. Repellent test was performed to evaluate the repellent activity of anti-insect sachet. In addition, the controlled release of FO from the anti-insect sachet was determined at $28^{\circ}C$ by gas chromatography (GC). It was demonstrated that FO was an effective substance against P. interpunctella. The mortality of FO was 56% at 800 mg/0.5 L in 120 h. In repellent test, the FO sachet showed effective repellency against P. interpunctella. The developed anti-insect sachet could be a promising source for insect repellent materials in food packaging.