• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.4
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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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• v.38 no.7
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• pp.814-820
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• 2014

Due to the development of human civilization, industrialization and urbanization, the human race demanded the food, clothing and shelter as well as a comfortable living environment. For the purpose of this, the refrigeration and air conditioning part was carried out research and development. However, high oil prices and environmental pollution having problems in the 21st century cannot be overlooked. As an alternative, thermal system was designed using the heat pump to applied sea water heat source. In this paper, outside and sea temperatures are analysed in 2010 and carried out the performance analysis simulation at All water and All Air heat pump system by HYSYS program for domestic use. As a result, total average COP of the system is 3.37 from All Water system and All Air is 3.48. It showed that high performance confirmed in both system.

• Korean Journal of Veterinary Research
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• v.44 no.1
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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.