• 한국공작기계학회논문집
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• 제13권4호
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• pp.100-105
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• 2004

Fin-tube type(Fin-type) heat exchanger has been tested in order to replace the heat exchanger of parallel flow type(P.F -type) which is now widly used in automobile air conditioning system The following conclusions are drawn by the comparison of the characteristics of the heat exchangers. Evaporator and condenser capacities and COP(Coefficience of performance) were varied as with the compressor speed, outdoor air temperature and air flow rate changed, which much influenced on the characteristics of the air conditioning system Evaporator and condenser capacities were increased with increasing compressor speed and outdoor air temperature. Evaporator and condenser pressures of Fin-type were decreased by 7% and 5% respectively compared with those of P.F-type. The COP of Fin-type was decreased with increasing outdoor air temperature and compressor speed. The COP of P.F-type was decreased by 14% compared with that of Fin-type.

• Journal of Advanced Marine Engineering and Technology
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• 제38권7호
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• pp.814-820
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• 2014

문명의 발전과 도시화, 산업화를 통하여 인류는 의식주의 해결뿐 아니라 더 낳은 생활환경을 추구하였다. 그 결과 냉동 및 공조 분야의 연구와 개발이 활발히 진행되어 왔다. 하지만 인류는 21세기에 들어 상승하는 고유가와 환경문제를 더 이상 간과할 수 없게 되었다. 그 대안으로, 해수의 열원을 이용한 열펌프의 개발이 진행되었다. 본 논문에서는 2010년의 해수와 대기의 온도를 분석하여 열펌프의 국내적용을 위한 성능평가 시뮬레이션을 HYSYS 프로그램을 이용하여 전수식과 전공기식에 적용하였다. 그 결과, 총 평균 성능계수는 전수식에서 3.37 그리고 전공기식에서 3.48을 기록하였다. 이와 같은 결과로 해수열원을 이용한 열펌프 시스템이 국내사용에 적합함을 알 수 있었다.

• 대한수의학회지
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• 제44권1호
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• pp.23-28
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• 2004

We established a new method to analyze moxidectin using high performance liquid chromatography(HPLC) with fluorescence derivatization in order to obtain its residual profiles in biological samples. Recovery of moxidectin in tissue was 62% at 10 ppb. Average detection reproducibility in terms of coefficience variation was 4.47% at 0.32 to 10 ppb. Residual of moxidectin was studied in 44 Yorkshire-Landrace mixed bred male pigs administered subcutaneously 0, 200, or $800{\mu}g/kg$ body weight (BW) Residual profiles of moxdectin in blood, muscle, liver, kidney and fat of pigs were described. The concentration of the moxidectin in liver after administration of moxidectin was the highest among the tissues examined. Moxidectin in liver after administration of moxidectin as $200{\mu}g/kg$ BW was declined from $10.0{\pm}3.7ng/g$ at 10 day post administration to $0.5{\pm}0.3ng/g$ level at 40 day post administration. Residual levels of moxidectin in all samples were estimated to fall below the limit of quantitation (0.32 ng/ml) after 50 day after treatment of $200{\mu}g/kg$. Moxidectin showed no abnormal observations in all the clinical findings at any concentrations under these experimental conditions. In conclusion, this analysis method by HPLC after fluorescence derivatization was very effective for the detection of moxidectin in biological samples. We suggest that 50-day is safe enough for the withdrawal time of moxidectin in pigs, following the recommendation dose by the manufacturer.