• 설비공학논문집
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• 제14권6호
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• pp.503-511
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• 2002

Heat flow characteristics during hot water extraction process was studied experimentally. Data were taken at various outlet port type for the fixed inlet port type, inlet-outlet temperature differences and mass flow rates. In this study, the temperature distribution in a storage tank and an outlet temperature were measured to predict a degree of stratification in the storage tank, and a useful rate of hot water was analysed with respect to the variables dominating a extraction process. Experimental results show that the degree of stratification and useful rate of hot water are all high in a low flow rate in case of using modified distributor I (MDI) as the outlet port type.

• 대한설비공학회지:설비저널
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• 제16권3호
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• pp.295-304
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• 1987

The purpose of this study is to develop a computer model for simulating the water-lit hium bromide absorption heat transformer (AHT) Including all major components and to find the flexibility in operation. The effect of source hot water temperature, cooling water temperature, useful hot water flow rate, cooling water flow rate and evaporator circulation flow rate were investigated. The coefficient of performance (COP), temperature boost $({\Delta}T\;=\;T_A\;-\;Ti)$ and concentration variations can be predicted. The performance study indicates that the performance of AHT increases for the waste hot water temperature increasing and with a decrease of the cooling water temperature. The effect on performances of useful hot water flow rape is significant except on temperature boost. Also the effects on performance of cooling water flow rate and evaporator circulation flow rate are small. It is shown that the computer program is valuable to predict the performance of absorp-tion heat transformer units at various working corditions.

• 태양에너지
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• 제18권3호
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• pp.71-80
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• 1998

In thermal energy storage system, energy collected from many types of heat source is stored in a storage tank and then supply to load for demand. Lately, practical use of thermal energy storage system and attention to essential use of energy have been increased. From this point of view, especially, a study about the energy extraction process from a storage tank is necessary. So in this study, useful rate of hot water and hot water extraction efficiency was analysed respect to dynamic and geometric parameters dominating the hot water extraction process.

• 태양에너지
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• 제13권2_3호
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• pp.45-52
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• 1993

현열저장에서 열성층의 이점을 태양열 주택에 적용해보았다. 성층으로 인하여 에너지 입력의 열이용 효율이 증가되는 효과가 논의되었고, 실험과 시뮤레이션을 통하여 설명되었다. 성층을 촉진시키기 위하여 Distributor를 사용하였으며, 본 실험에서 Q=8 liter/min, ${\Delta}T=40^{\circ}C$일 때, 최대 90%의 열이용 효율을 얻을 수 있었다. 한편 성층을 촉진시키기 위하여 Distributor의 적은 구멍에서 나오는 유동(속도와 압력)이 같게 제작할 수만 있다면 그 이상의 열이용효율도 얻을 수 있음이 입증되었다.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2005년도 연구개발 발표회 논문집
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• pp.448-453
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• 2005

Temperature Control Valve (TCV) is one of the useful temperature control devices, which is used to control constant temperature of working fluid in power and chemical plants and domestic water supply systems. TCV is composed of body, cylinder and piston, and the body shape has a symmetrical H-type. In general, it has several inlet and outlet holes, and its shape is like as tubular sleeve. The piston has three rings two rings of the end of piston have the function of controlling inlet flow rate with hot and cold working fluids, the center ring has the function of preventing hot and cold water from intermixing. Consequently, the shapes of piston and cylinder are the main design parameters in the performance of TCV. In this study, numerical analyses were carried out with two different piston and cylinder shapes to investigate the functions as a temperature control valve and the flow characteristics according to piston opening grade in TCV. Using a commercial code, FLUENT, velocity and pressure fields in TCV are obtained under steady, standard $k -{\epsilon}$ turbulence model and no-slip condition.

• 동의신경정신과학회지
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• 제20권3호
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• pp.49-64
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• 2009

Objectives : The water and methanol extracts of Aconitum carmichaeli(Aconiti Tuber Preparat) were investigated for their anti-depressant effects. Methods : In this study, reserpine-induced hypothermia test, tail suspension test and hot plate test. Additionally, the brain monoamine oxidase activity was determined in vivo. Results: In the reserpine-induced hypothermia test, both extracts suppressed the fall of body temperature compared to the control group in a dose-dependent manner, suggesting the inhibition on hypothermia. In the tail suspension test, the methanol extract dose-dependently reduced the duration of immobility by 28.4% at a dose of 1 g/kg compared to control group, which is more effective than the water extract. In the hot plate test, the water extract and methanol extract increased the jump latency time compared to the control group, showing the inhibition rate of 198% and 182%, respectively, at a dose of 1 g/kg. Methanol extracts potently inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, showing 84.6% inhibition, but the water extract revealed very weak activity. Conclusions : Above results suggested that the extract of Aconitum carmichaeli can be useful for the prevention and treatment of depression.

• 한국식품영양과학회지
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• 제34권6호
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• pp.790-796
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• 2005

복분자의 열수추출물과 에탄올 농도별 추출물의 항산화 및 생리 활성효과를 비교하였다. 각 추출물의 총 페놀 함량은 열수추출물에서 41.4 mg/g으로 가장 높았으며, 에탄올 추출물은 $60\%$에서 41.3 mg/g으로 높았다. 복분자 추출물의 항산화 효과는 ABTS가 $60\%$ 에탄을 추출물에서 99.8$\%$, 열수추출물에서 $99.3\%$로 나타났으며, PF는 1.3, 1.2, DPPH가 $93.3\%$, $91.1\%$, TBARS가$ 0.03(\times\;100\mu M),\;0.04(\times\;100\mu M)$로 나타났다 복분자 추출물의 생리활성효과는 XOase 활성억제 효과와 pancreatin $\alpha$-amylase 활성억제효과가 열수추출물이 $60\%$ 에탄을 추출물보다 높았으며, ACE 활성억제효과는 열수추출물과과 $60\%$ 에탄올 추출물이 같은 활성억제효과를 나타내었다. 복분자 추출물로부터 생리활성효과에 영향을 미치는 페놀물질을 알아보기 위해 4가지 페놀화합물인 protocatecuic acid, caffeic acid, courmaric acid, rosemarinic acid를 선정하여 HPLC로 분석해 본 결과 $60\%$ 에탄을 추출물과 열수추출물 모두 protocatecuic acid가 12.5 mg/g, 10 mg/g으로 4가지 페놀화합물 가운데 가장 많이 검출되었다. 이상의 결과로 복분자 추출물의 생리활성효과는 천연항산화제 및 기능성 식품으로 이용 가능할 것으로 판단되었다

• 설비공학논문집
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• 제3권4호
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• pp.276-285
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• 1991

The transient heat transfer characteristics in the radiant heating panel were predicted by numerical analysis. Thermal behaviors of panel, such as temperature distributions in panel and convective and radiative heat fluxes in panel surface with respect to time were obtained. Heating hours per day, rate of energy supplied and maximum temperature differences at panel surface were also compared for several important parameters. The performance and thermal comfort of heating panel were studied and compared for various operating and design conditions such as pipe pitch, pipe location, pipe diameter and flow rate of hot water for the purpose of producing useful data, which can be used for the test and decision of efficient operating condition of the conventional heating systems or the optimal design of the new panel heating systems.

• 한국작물학회지
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• 제68권4호
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• pp.371-382
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• 2023

본 연구는 온탕침지법과 석회유황합제 처리가 유기농 조경밀, 금강밀, 새금강밀 및 백강밀 종자의 발아와 소독에 미치는 영향을 구명하고자 수행하였다. 4종의 밀 품종은 소독 전 종자의 발아율이 평균 86.3±2.5~87.5±2.9%이었으나 곰팡이와 세균에 의한 감염 정도는 각각 평균 22.5±2.9~38.3±2.5%, 18.8±4.8~23.8±2.5%로 나타났다. 4종의 밀 품종에 대한 온탕침지 조건에 따른 종자의 발아율은 무처리에 비해 동일하거나 높았으며 온탕침지 온도와 처리 시간이 증가할수록 곰팡이와 세균의 오염도가 감소하였다. 밀 종자에 대한 최적 온탕침지 조건 55℃에서 10분간 처리하는 것이 무처리에 비해 발아율이 평균 90.0±0.0~97.5±2.9%로 동일하거나 높았고 곰팡이와 세균의 소독효과는 각각 평균 83.3~93.5%와 100%로 높았다. 또한, 0.2%와 0.4% 석회유황합제의 처리시간에 따른 밀품종별 발아율과 곰팡이, 세균의 소독효과를 조사하였더니, 처리 시간의 경과에 따라 밀 품종 간에 발아율의 차이를 보이지 않았으나 무처리(86.3~87.5%)에 비해 발아율이 높았고 최적 처리 시간은 7분 또는 10분으로 곰팡이와 세균의 오염도를 평균 90.0~96.0% 감소시켰다. 따라서 4종의 유기농 밀 종자 소독을 위해 적용한 온탕침지와 석회유황합제의 처리 조건에 따라 발아율과 소독효과의 차이는 있으나 55℃, 10분 온탕침지 처리를 하거나 0.2% 또는 0.4% 석회유황합제를 10분간 처리하는 것이 무처리에 비해 발아율을 증진하고 종자에 오염된 곰팡이와 세균의 밀도를 감소시켜 친환경적인 밀 종자 소독기술로 농업현장에서 활용도가 높을 것으로 판단된다.

• 동의신경정신과학회지
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• 제16권1호
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• pp.171-183
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• 2005

Objective : The Korean famous medicinal prescription of Subi-jeon was investigated for their antidepressant effects by tail suspension test, hot plate test, reserpine-induced hypothermia test. In addition, the monoamine oxidase activity was determined in vivo. Methods : The methanol extract reduced dose-dependently the duration of immobility in the tail suspension test, by 31.4 and 34%(p<0.05) at doses of 500mg/kg and 1g/kg, respectively, compared with control group. In comparison with this, the effect of the water extract was very weak. Results : 1. In the hot plate test, the methanol extract potently increased the jump latency time(p<0.05) compared to the control group, exhibiting the inhibition rate of 197% and 256% at doses of 500mg/kg and 1g/kg(per os), respectively, which is more effective than the water extract. 2. Both extracts suppressed the fall of body temperature induced by reserpine(reserpine-induced hypothermia) in a dose-dependent manner, showing the less effect at lower doses and better effect at higher doses compared to the water extract. 3. Both extracts inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, the activity of water extract was better than that of the methanol extract. Conclusion : The prescription of Subi-jeon can be useful for the prevention and treatment of depression.