• 한국의류학회지
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• 제29권11호
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• pp.1454-1464
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• 2005

The study was based on a three-stage, non-repetitive factorial experiment in which chemical-rotted kenaf fibers were treated separately with hydrogen peroxide concentrations of $0.5\%,\;1\%\;and\;2\%$, with pH solutions of 7, 9 and 11, and treatment times of 30, 60 and 90 minutes. Under optimal conditions, the study was conducted to determine the strength and elongation of kenaf fibers by the addition of chelators, penetrants and surfactants. The hydrogen peroxide concentration, solution pH and treatment time directly affected the strength of kenaf fibers. The hydrogen peroxide concentration, solution pH affected the elongation of kenaf fibers. It was found, however, that the interaction between pH and treatment time, concentration and treatment time, concentration and treatment time and pH affected the strength of kenaf fibers. Also, It was found that the interaction between pH and concentration, concentration and treatment time, concentration and treatment time and pH affected the elongation of kenaf fibers. Under the hydrogen peroxide conditions of $2\%$ concentration, pH 11 and a treatment time of 60 minutes, there were no effects on the strength and elongation of kenaf fibers with the addition of chelator SP, CA.

• 한국수정란이식학회지
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• 제11권3호
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• pp.225-231
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• 1996

This study was conducted to investigate the effects of preincubation time, concentration and exposure time of sperm on in vitro fertilization of porcine follicular oocytes rnatured in in vitro. The results obtained are as follows ; 1. Effect of preincuhation time for porcine sperm capacitation on in vitro fertilization in medium with heparin was investigated. Normal fertilization rate was highest in 15 min(26.4%). However, there were no significant differences among preincuhation times of 5~90 min, 2. Normal fertilization rates of sperm concentrations were 17.0~26.5%, and normal fertilization rate from l$\times$ l05cell /ml concentration was also higher than those of other sperm concentration. 3. Normal fertilization rates of sperm exposure time of 4, 8, 12, 16 and 20 hours were 6.1, 20.8, 27.8, 25.0 and 26.7%, respectively. Normal fertilization rate from sperm exposure time of 12 hours was also higher than that of other sperm exposure times.

• 한국식품과학회지
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• 제33권3호
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• pp.294-300
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• 2001

저장 방법의 차이에 따른 유과의 과산화물가는 대바구니 포장이 가장 높았으며, 질소 치환 포장, 냉동 저장 순으로 나타났고, 저장 기간 증가에 따라 현저히 증가하였다. 콩물 농도가 증가함에 따라 과산화물가도 증가하였으나 incubation 시간 증가에 따른 차이는 유의적이지 않았다. 유과의 hardness는 콩물 농도, incubation 시간과 저장 기간의 증가에 따라 현저한 감소를 나타냈으나 저장 방법간에는 유의적인 차이를 나타내지 않았다. Peak number는 저장 기간 10주까지는 냉동 저장군이 다른 군보다 높게 나타났으나, 12주에는 이러한 차이가 나타나지 않았고, 저장 기간 증가에 따라서 증가하였다. 저장 3개월 후 관능 검사 결과, 유과의 색은 저장 방법과 콩물의 농도에 따라서 용적 증가율은 콩물 농도와 incubation 시간에 따라 유의적인 차이가 있었다. 산패취는 저장 방법에 따라서만 유의적인 차이가 있었으며, 부드러운 정도, 맛, 종합적 기호도는 콩물의 농도에 따라서만 유의적 차이가 있었다.

• 한국식생활문화학회지
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• 제17권1호
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• pp.70-77
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• 2002

Jangachi(salted and fermented vegetable) has been made by Korean traditionally using several kinds of vegetables, which is a good source of variety of nutrients and vitamins. There are many methods for making Jangachi. Generally soy sauce Jangachi is made through two steps. First, as a pretreatment, vegetables are soaked in salt water. Second, soaked vegetables are fermented in various ingredients like soy sauce, sugar, garlic, ginger and so on. This study was performed to observe changes in contents of chemical components and sensory evaluation of pretreated perilla leaf. Perilla leaf was soaked in water with different levels of salt concentration(2, 5 and 8 %) and soaking time(1, 3 and 5 days). The optimal level of salt and soaking time was determined with the results of sensory evaluation by response surface methodology and analysis of composition. The moisture contents decreased as the levels of salt and soaking time increased. The moisture content of untreated sample was 87.5 % and when soaked for 5 days in the water of 8 % salt concentration, it became 78.27 %. pH of Perilla leaf was high in high levels of salt concentration and short soaking time. Total acidity was so opposite to pH that was low in high levels of salt concentration and short soaking time. In the water of 8 % salt concentration, total acidity was 0.14 % when soaked for 1 day, 0.20 % for 3 days and 0.30 % for 5 days. Salt contents became greater as the soaking time increased. As the results of puncture test, soaked Perilla leaf's toughness increased as the levels of salt increased and soaking time decreased. Among the sensory attributes, greenness increased as the levels of salt concentration increased when soaked for more than 3 days. Saltiness and bitterness became greater as the levels of salt concentration increased. Perilla flavor decreased with the short soaking time. Off-flavor increased with the increased levels of soaking time and decreased salt concentration when soaked for more than 3 days. Toughness decreased as the levels of soaking time increased. Crispness increased with the increased levels of salt concentration. The condition of pretreated Perilla was optimum when it soaked for 42 hours in 4 % salt concentration.

• 한국환경과학회지
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• 제11권12호
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• pp.1243-1252
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• 2002

This paper aims to find the characteristics of concentration distribution of coastal urban air pollutants. For this purpose, It was used the daily meteorological data and the hourly concentration data for $O_3$and NO$_2$ in Busan metropolitan city from 1994 to 1996. It was investigated the annual and monthly distribution of ozone and nitrogen dioxide concentration at each site in Busan, and also investigated the characteristics of concentration change of air pollutants with time under the sea breeze. As a results, the concentration of nitrogen dioxide and ozone tend to be increased every year and nitrogen dioxide concentration is higher than ozone concentration at all sites in Busan. The concentration of ozone is high in summer season and low in winter season, but the concentration of nitrogen dioxide have a reversed trend. The monthly peak concentration of ozone occurred in April and September, while the monthly minimum concentration of nitrogen dioxide occurred in August. Their trend were identified by sites near the coastline than sites stands apart from the coastline. The sea breeze occurred annual mean 81 day in Busan from 1994 to 1996. The main wind direction of sea breeze was classified into southwesterly and southeasterly. In case of southwesterly, It was pronounced the south wind and southwest wind. In case of southeasterly, the occurrence frequency of east wind was high. Especially, the concentrations of urban air pollutants, such as ozone and nitrogen dioxide, were high on time which the sea breeze flow, and the areas that ozone concentration was high moved from outside part to central part of city with time. In costal urban such as Busan, the wind direction of sea breeze is influenced the change of ozone and nitrogen dioxide concentration on time which the sea breeze flow at each site and also influenced the change of air pollutants concentration of sites on the pathway of sea breeze.

• International Journal of Air-Conditioning and Refrigeration
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• 제13권2호
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• pp.89-98
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• 2005

In this study, indoor VOCs concentration emitted from floor and furniture was measured after the installation of floor and furniture in a real residence. With the measured data, prediction method and predication equations for indoor concentration of each VOCs and BTEX were developed. The following conclusions were drawn from this study. First, according to the predicted results of concentration decrease of BTEX (benzene, toluene, ethylbenzene, m,p,o-xylene) after the installation of floor in a real residence, prediction equation can be expressed using exponential function. Second, in case of floor, more reliable prediction equation can be obtained by using cumulative value of indoor concentration than by using just hourly measured value directly. Indoor concentration of benzene can be expressed as $y=408.52(1­e^{-00031{\times}time})$ with $R^2$ of 0.94 which is significantly high value. Third, toluene showed the highest concentration in case of furniture installation indoors, and it needed the longest time for concentration decrease. However, other substances except toluene showed constant concentration throughout the measurement period. Fourth, in case of furniture installation indoors, prediction equation of toluene concentration decrease is estimated to be $y= 3616.3{\times}e^{(-0.1091{\times}time)}+513.96{\times}e^{(-0.0006{\times}time)}\;with\; R^2$ of 0.95 which is significantly high value.

• Journal of Pharmaceutical Investigation
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• 제12권2호
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• pp.31-36
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• 1982

The effect of some surfactants, such as tween 40, tween 80, span 80, and triethanolamine, on the absorption of lidocaine was studied using goldfish as a model of absorption kinetics. This model was believed that reciprocal overturn time and death time were the occurrence of biological effect versus drug absorption. The results were as follows; The threshold concentration of lidocaine was significantly reduced by the surfactants. Overturn time and death time of goldfish in the lidocaine solution were reduced by such surfactants as tween 40, tween 80, span 80 and triethanolamine, and more reduced with increasing concentration of surfactants except tween 40 and tween 80. The plots of reciprocal death time versus lidocaine concentration were linear relationship with a positive concentration intercept such as minimum effective concentration (0.2-0.8%). As results it is believed that these surfactants may form complexes with lidocaine or affect the goldfish membrane to make more permeable to lidocaine, which is adsorbed more rapidly.

• 한국식품저장유통학회지
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• 제16권6호
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• pp.908-914
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• 2009

본 연구에서는 프로폴리스의 다양한 효능을 이용한 식품 소재 개발을 위해 반응표면분석을 이용하여 프로폴리스의 에탄올 추출농도(50, 60, 70, 80, 90%)와 추출시간에 따른 항산화능, 플라보노이드 등의 품질특성을 조사하였다. 총 페놀성 화합물 함량은 에탄올 농도가 높을수록 증가하다가 80% 이상에서는 감소하는 것으로 나타났으며, 추출시간보다는 에탄올 농도에 더 큰 영향을 받는 것으로 나타났다. 추출물의 전자공여능은 에탄올 농도가 높을수록, 추출시간이 짧을수록 전자공여능이 증가하였으며, 추출시간보다는 에탄올농도에 더 큰 영향을 받는 것으로 나타났다. 항산화능이 가장 높은 범위는 에탄올 농도 65~75%, 추출시간 2.2~3.6시간이었다. 추출물의 아질산염소거능은 에탄올농도가 높을수록 증가하였고, 추출시간이 짧을수록 증가하는 경향을 나타내었다. 총 플라보노이드 함량은 에탄올 농도 68~82% 및 추출시간 2.4~3.7시간 범위에서 최대 함량을 나타내었으며, 에탄올 농도 및 추출시간 모두에 영향을 받는 것으로 나타났다. 에탄올 농도, 추출시간에 따른 반응표면을 superimposing하여 얻은 프로폴리스의 최적 추출조건의 범위는 에탄올 농도 72-82%, 추출시간 2.2-3.3시간 범위인 것으로 나타났다.

• Toxicological Research
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• 제19권2호
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• pp.99-104
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• 2003

This study was aimed to evaluate the effect of oxygen on motor activity and toxicity in male mice. The modified Porsolt forced swim test (FST) was used and the distance and time of movement by mice were analyzed in 15。C water bath for 20 minutes using the automatic Ethovision videotracking system. Analyses were carried out before and after 20 minutes of exposure to 10％-70％ concentration of normobaric oxygen. The effects of inspired oxygen tension on the distance and time of movement showed the similar trends, but changes in distance were more prominent. Both the distance and time of movement increased after exposure to 30％ and 40％ oxygen concentration. The distance and time of movement also increased upon exposure to 50％ and 60％ oxygen. In contrast, increases En movement and time under exposure to 21％ oxygen concentration were suppressed when exposed to over 50％ oxygen concentration. With exposure to 10％ oxygen, there was a significant decrease in the distance of movement and a slight suppression of movement time. During the swim test, 12.5％, 37.5％, and 87.5％ of the mice drowned after exposure to 10％, 60％, and 70％ oxygen concentration, respectively. These results suggest that motor activity can be enhanced by inspired oxygen up to 40％ concentration. When hypoxic and hyperoxic oxygen exposure over 50％, motor activity is reduced and toxicity may be induced.

• 대한물리치료과학회지
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• 제19권3호
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• pp.17-22
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• 2012

Background : The purpose of this study was to investigate the relationship between an agility and a concentration, an auditory reaction time and a muscle power. Methods : Twenty one healthy female college students who were 20-21 years participated in the experiment; after being introduced to the methods, they voluntarily signed a consent form. And they received several test related with this study; side step test for an agility, Harris & Harris test for a concentration, brain auditory evoked potential test for an auditory reaction time and vertical jump test for a muscle power. Result : There was no relationship between the agility and the concentration and the auditory reaction time. However, the muscle power related with the agility significantly. Conclusion : In conclusion, these findings suggest that a muscle power training is a good way to promote an agility. So, we can find out that, in an player who requires an agility, a muscle power training is the most important way for promoting an agility than a concentration training or an auditory reaction time training.