• 한국농공학회지
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• 제45권1호
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• pp.91-101
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• 2003

Boryeong Seadike located at southwestern seashore of Korean peninsula completed in 1997. Sluice gate operation can be an important factor to maintain lake water quality and reduce retaining time of pollutants within lake. The lake water quality simulation model, WASPS was adopted and tested to find out proper gate operation timing and discharge amount. From the simulation of sluice gate operation, the results showed that the later the time of discharge for loosing 1 day successively to 6 days, the better the quality of water. Discharge amount showed relatively minor changes of water quality. This means that pollutants flowed into lake from watershed do not have enough time to mix up with deep water when the gate opened at early time. About 3 days delay of discharge caused the dilution effect to stabilize the lake water quality in case of Boryeong freshwater lake.

• 한국축산식품학회지
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• 제36권4호
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• pp.435-444
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• 2016

This review addresses the role of fat in beef palatability and healthfulness. Particular emphasis is placed on the content of oleic acid in beef, and how this increases with time when cattle are fed a grain-based diet. Oleic acid decreases the melting point of lipids from beef, increasing the perception of juiciness and improving beef flavor. Clinical trials have demonstrated that ground beef containing elevated oleic acid increases, or at the least has no negative effects on the concentration of HDL cholesterol. The amount of fat in published ground beef intervention trials greatly exceeds the amount of fat in equivalent portions of beef from U.S. domestic or Korean Hanwoo cattle. Thus, we conclude 1) Beef cattle should be raised under production conditions that increase the concentration of oleic acid in their edible tissues (i.e., by grain feeding over extended periods of time); and 2) The amount of fat consumed in a typical portion of beef will not increase risk factors for cardiovascular disease.

• 동아시아식생활학회지
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• 제15권3호
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• pp.334-339
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• 2005

This study was conducted to test the white bread dough with substitution of 1, 2, 3, 4 and $5\%$ kimchi powder on farinograph, extensograph, amylograph, and pH to find the dough development time, stability, extensibility, resistance to extension, temperature at gelatinization, and temperature at maximum viscosity. Dough with kimchi powder showed less moisture absorption than control. Upon increasing amount of kimchi powder, pH was decreased and dough development time was increased Extensibility of dough showed negative correlation with amount of kimchi powder added Gelatinization temperature increased but maximum viscosity temperature decreased as the amount of kimchi powder increased Overall, the samples with substitution of kimchi powder showed better extensibility than the control sample at the first fermentation.

• 한국환경보건학회지
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• 제24권2호
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• pp.145-150
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• 1998

This study was carried out to investigate the loss amount of collection at the different of precipitatation time, high voltage and gas speed. This work has focused on the dependence of the collection efficiency in the collector zone with gas speed and high voltage. This advanced Model is developed by research of the different parameter as the conventionnal modem of study. In order to investigate collection efficiency of electrostatic precipitator, the loss amount of knocking was measured with Monitek-Treubung and the particle size was analyzed by He-Ne laser diffraction spectroscopy.

• 한국치위생학회지
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• 제15권6호
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• pp.1063-1071
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• 2015

Objectives: The purpose of the study is to investigate the quantitative detection of periodontal pathogens before and after scaling by real-time polymerase chain reaction. Methods: Participants were voluntarily recruited at D university, and saliva samples were extracted before and after scaling. Multiple real-time polymerase chain reactions were used to analyze characteristics and the amount of nine kinds of periodontal pathogens; Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Parvimonas micra, Campylobacter rectus, and Eikenella corrodens. Results: After scaling, most periodontal pathogens except Eikenella corrodens were significantly decreased in all subjects(p<0.05). In addition, the percentage of microorganisms associated with disease, the microorganism risk index of periodontitis and the prevalence of red complex, orange complex, and Aggregatibacter actinomycetemcomitans was also significantly reduced after scaling(p<0.05). Conclusions: Scaling decreased in the amount of major periodontal pathogens and periodontitis prevalence rate.

• 지질공학
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• 제18권2호
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• pp.207-214
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• 2008

점토함량에 따른 미고결 이암의 시간 의존적 변형을 비교하기 위해 측방변형이 구속된 상태에서의 일축압밀시험을 수행하였다. 미고결 이암의 변형은 응력의 증가에 따른 즉각적인 변형과 일정한 응력 하의 크리프 변형으로 구분되었다. 응력 증가분이 동일한 경우에 시간 의존적 변형은 거의 일정한 크기로 발생하였으며 응력 증가분이 증가할수록 크리프변형의 크기도 증가하여 선형점성변형의 특성을 보였다. 점토함량이 증가함에 따라 시간 의존적 변형은 증가하는 경향을 보여 점토가 이암의 시간 의존적 변형 발생에 중요한 역할을 하는 것으로 사료된다. 크리프 변형은 시간에 따라 지수함수 형태를 보여 크립 모델 중 하나인 power-law 모델로 잘 예측될 수 있었다.

• 한국초등수학교육학회지
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• 제14권2호
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• pp.421-440
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• 2010

본 연구에서는 시간 지도 개선에 관한 시사점을 찾고자 한국, 싱가포르, 일본의 초등학교 수학교과서를 비교 분석하였다. 연구 결과에 따르면, 우리나라는 두 나라에 비해 시간의 덧셈과 뺄셈의 사칙 계산과 그 알고리즘이 강조되고 있었다. 또한 두 나라에 비해 시간 지도 요소 항목이 많이 편이었으며, 소재와 시계 모형에 있어서도 유사한 것들이 반복 사용되고 있었다. 마지막으로 시간의 흐름이 적게 반영되어 있었다.

• Journal of the Korean Wood Science and Technology
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• 제36권3호
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• pp.39-46
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• 2008

고밀도 우드세라믹을 제조하기 위한 기초연구로서 수지함침율에 따라 제조된 1차 탄화 우드세라믹을 수지 재함침 후 2차 탄화하여 우드세라믹을 제조하고 그 물리적 성질을 조사하였다. 1, 2차 탄화 우드세라믹의 성질 비교에서 수지함침율이 증가함에 따라 2차 탄화 후 중량 및 밀도증가율은 감소하였고, 수지함침율 40%일 때 1차 탄화 시보다 중량은 23.8%, 그리고 밀도는 30.0% 증가하여 최고치를 나타냈다.

• 가족자원경영과 정책
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• 제17권2호
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• pp.75-91
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• 2013

This study is focused on the amount of time spent on child care by mothers with preschool children with developmental disabilities. It is designed to find out how much time mothers spend taking care of their children and to identify related factors. The subjects of this study are 162 mothers of children with developmental disabilities residing in Seoul. The findings are as follows: First, mothers with preschool children with developmental disabilities spent 6 hours and 50 minutes per day caring for their children during weekdays and 6 hours and 10 minutes on weekend days. This is double the amount of time spent by the average mother with preschool children. Second, mothers spent much more time caring for their disabled children than they do for their children without disabilities. Third, determinants of a mother's time for caring their disabled child during weekdays were mother's employment, the number of children, and gender of the disabled child. On weekend days, determinants of mother's care time were the number of children and husband's help for childrearing.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.454-457
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• 1997

The purpose of this study is to develop an optimal model, using existing models, that is able to estimate the amount of spatter utilizing artificial neural network in the short circuit transfer mode of gas metal arc (GMA) welding. The amount of spatter generated during welding can become a barometer which represents the process stability of metal transfer in GMA welding, and it depends on some factors which constitute a periodic waveforms of welding current and arc voltage in short circuit GMA welding. So, the 12 factors, which could express the characteristics for the waveforms, and the amount of spatter are used as input and output variables of the neural network, respectively. Two neural network models to estimate the amount of spatter are proposed: A neural network model, where arc extinction is not considered, and a combined neural network model where it is considered. In order to reduce the calculation time it take to produce an output, the input vector and hidden layers for each model are optimized using the correlation coefficients between each factor and the amount of spattcr. The est~mation performance of each optimized model to the amount of spatter IS assessed and compared to the est~mation performance of the model proposed by Kang. Also, through the evaluation for the estimation performance of each optimized model, it is shown that the combined neural network model can almost perfectly predict the amount of spatter.