• 한국태양에너지학회 논문집
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• 제22권1호
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• pp.67-72
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• 2002

Solar Air Systems (SAS) have unique advantages for space heating and tempering ventilation air. Air, unlike water, needs no protection against freezing nor are leaks damaging to the building structure or its contents. In contrast to glazed collector, unglazed steel solar collector may have higher efficiencies over glazed flat collector due to the absence of the glass. Therefore, the monitoring of SAS is so important to evaluate actual performance of SAS for right applications. This study is to provide a testing method with a movable test cell developed in KIER to evaluate the thermal performance of SAS based on international standard method ASHRAE 93-86, "Method of Testing to Determine the Thermal Performance of Solar Collectors". The monitoring tool used advanced technique LabVIEW 6i with portable notebook computer. Sample results have been obtained to access the performance of a reference and a target SAS module. The process and tool introduced here could be used to provide a performance verification data for future implementation study applications.

• 수산해양기술연구
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• 제50권1호
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• pp.67-74
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• 2014

Most of steam power plants in Korea are using the method of heating the feed water whenever the ambient temperature around the power plant area below $5^{\circ}C$ to prevent freezing water flowing in the pipe in winter time. But this kind of heat supplying system is not useful to save energy. If we take the method that the temperature of the each pipe is controled by direct measure of temperature by attaching sensor on the outside surface of the feed water tubes, then we can expect that a plenty of energy can be saved. In this study, the computer simulation is used to compare the energy consumption loads of both systems. Energy saving rate is calculated for the location of Incheon area in winter season. Four convection heat transfer coefficients for the ambient air and three initial flowing water temperature inside the tube were used. The result shows that the temperature control system using sensor represents more than 95% of energy saving rate in Incheon area. Even in the severe January weather condition, the energy saving rate is almost 75% in two days basis and even 83% in one day basis.

• KSBB Journal
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• 제29권1호
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• pp.22-28
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• 2014

In this study, we investigate the effect of pretreatment method on lipid extraction from Enteromorpha intestinalis using physical, thermo-chemical, and enzymatic process such as ultrasonication, high temperature treatment, freezing, microwave irradiation, osmotic shock, pH shock, homogenizing, and enzymatic treatment. In pretreatment with separated lipid extraction, the high extraction yield was obtained by high temperature treatment ($121^{\circ}C$ for 5 min) with 0.1 N HCl, which is 1.4 times higher than that of control. In pretreatment with direct lipid extraction, the high extraction yields were obtained by 0.1 N HCl pretreatment, microwave irradiation (700W, 1 min with twice), and 10% NaCl pretreatment, which is 1.45 times higher than that of control. In the result of enzymatic pretreatment with 17 kinds of enzymes, Cellic CTec II showed the high extraction yield of 5.3%, and which is 1.9 times higher than that of control. Moreover, the extraction yield was increased by the increase of enzyme amounts. In 10% enzyme amount, about 5.8% yield was obtained.

• Archives of Pharmacal Research
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• 제14권4호
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• pp.298-304
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• 1991

Isoprinosine, an antiviral agent with a bitter taste, has been clinically used up to a maximum of 4 g daily in 4-8 doses. In this investigation, isoprinosine was microencapsulated with ethylcellulose 22 cps, 50 cps and 100 cps by means of polymer deposition from cyclohexane through temperature change. Complete removal of cyclohexane from the microcapsules was necessary, since ethylcellulose-coated microcapsules obtained from cyclohexane medium were heavily solvated with cyclohexane and formed lumps even after drying. The displacement of cyclohexane by n-hexane during isolation of microcapsules (Method III) or the freezing of the anal-washed microcapsules before drying (Mothod II) provided the dried products which were more discrete microcapsules than those which were simply dried in the air overnight (Method I). Method III was especially the most effective procedure in preparing finer and more discrete microcapsules. The drug-release from microcapsules was influenced by the ratio of core to wall, the viscosity grade of ethylcellulose and the overall microcapsule size. The release rate was adequately fitted to both the first-order and the diffusion-controlled processes. It is therefore possible to design the release-controlled microcapsules with ethylcellulose of different viscosity along with various core to wall ratio.

• 한국구조물진단유지관리공학회지
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• 제18권4호
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• pp.2-8
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• 2014

본 고는 동절기 이후 무근 콘크리트의 상부에서 쉽게 발생하는 스케일링 현상에 주목하여 무근 콘크리트의 동해 발생원인을 고찰하고, 이에 대한 내구성을 향상시키기 위한 방안을 기존문헌조사를 통하여 1) 강도향상, 2) 진공배수공법 적용, 3) 흡수방지재 시공의 방법을 선정하였다. 그 후 각 방법의 동결융해저항성 향상 평가를 정량적으로 평가하기위하여 동결융해 시험을 통한 상대동탄성계수를 측정하였다. 그 결과 1), 2)번의 경우 동탄성계수가 약 15% 향상, 3)의 경우 강도에 따라 7~13%향상됨을 실험적으로 확인하였다. 따라서 상기의 방법 모두 무근 콘크리트의 동결융해 저항성 향상에 유효한 방법으로 판단되며, 이를 통해 무근콘크리트의 빈번히 발생하는 품질저하 및 이로인한 유지보수비용 절감을 도모할 수 있을 것으로 사료된다.

• 대한약침학회지
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• 제11권3호
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• pp.93-97
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• 2008

Objective: This study was done to investigate the safety of Fel Ursi pharmacopuncture solution manufactured with freezing dryness method to use eye drop. Methods: The eye irritation test of this material was performed according to the Regulation of Korea Food & Drug Administration(2005. 10. 21, KFDA 2005-60). After Fel Ursi pharmacopuncture solution was medicated in the left eye of the rabbits, the author observed eye irritation of the cornea, iris, conjunctiva at 1, 2, 3, 4 & 7day. Results: 1. After Fel Ursi pharmacopuncture solution was medicated in the left eye of the rabbits, there wasn't physical problem at 9 rabbits. 2. After Fel Ursi pharmacopuncture solution was medicated in the left eye of the rabbits, there wasn't eye irritation of the cornea, iris, conjunctiva at 1, 2, 3, 4 & 7day. Conclusions: I suggested that Fel Ursi pharmacopuncture solution didn't induced eye irritation in rabbits.

• 대한약침학회지
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• 제11권3호
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• pp.99-104
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• 2008

Objective: This study was done to investigate the safety of Fel Ursi & Bovis Calculus pharmacopuncture solution manufactured with freezing dryness method to use eye drop. Methods: The eye irritation test of this material was performed according to the Regulation of Korea Food & Drug Administration(2005. 10. 21, KFDA 2005-60). After Fel Ursi & Bovis Calculus pharmacopuncture solution was medicated in the left eye of the rabbits, the author observed eye irritation of the cornea, iris, conjunctiva at 1, 2, 3, 4 & 7day. Results: 1. After Fel Ursi & Bovis Calculus pharmacopuncture solution was medicated in the left eye of the rabbits, there wasn't physical problem at 9 rabbits. 2. After Fel Ursi & Bovis Calculus pharmacopuncture solution was medicated in the left eye of the rabbits, there wasn't eye irritation of the cornea, iris, conjunctiva at 1, 2, 3, 4 & 7day. Conclusions: I suggested that Fel Ursi & Bovis Calculus pharmacopuncture solution didn't induced eye irritation in rabbits.

• 한국포장학회지
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• 제11권2호
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• pp.75-79
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• 2005

With three kinds of agricultural products such as perilla leaves, this research is focussed on how to keep a freshness of agricultural products during long time transport by sea. In case of export fresh agricultural products by sea, research on products loading method onto the pallet is very important factor for keeping effective cold air circulation inside the freezing marine container. Details are as follows: Clear examination of palletization for cold air ventilation inside the container. Optimization of package dimension for best loading efficiency onto the standard pallet. Best layout of palletized products inside the container. Research for the change of circumstance and product quality inside the pack.

• 설비공학논문집
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• 제23권5호
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• pp.327-333
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• 2011

In the present work, a new freeze protection method has been proposed for a natural circulation system of solar water heater. Though electrothermal wire is popularly used for the purpose, there are freezing troubles by wire cut-off and shortage of excessive electric power consumption. In the experimental device, hot water in storage tank was used to heat the outlet pipe from the tank if the pipe surface temperature falls lower than a set point. The cold water pipe to the storage tank was installed to directly contact the hot water pipe surface temperature rose by transferred heat.

• International Journal of Industrial Entomology and Biomaterials
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• 제27권1호
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• pp.180-184
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• 2013

Recently, silk sericin has attracted the attention of researchers owing to its useful properties as a biomaterial including 1) good wound healing and cell activities, 2) fast gelation character, and 3) high water retention property. In the present study, silk sericin was prepared using different extraction times in hot water and the effect of extraction time on the rheological properties of sericin solutions and gels was examined. It was found that the production yield of sericin increased with extraction time. The shear viscosity of sericin solutions and gels decreased with increasing extraction time due to a decrease in sericin molecular weight. When the sericin solution transformed to a gel, the viscosity increased and the shear thinning behavior was more evident. In addition, the shear stress measurements indicated that the slip between the sericin samples and the measuring plate of the rheometer was increased by the gelation of sericin. The compression strength of sericin gel could be increased remarkably (by more than 100 fold) by preparation using the freezing and thawing method.