• 한국식품영양과학회지
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• 제34권10호
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• pp.1572-1578
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• 2005

인삼을 세절하여 동결건조 시킨 후 가열에 따른 성분변화의 특성을 살펴보고자 가열온도(130, 145, 160, 175, 190$^{\circ}C$) 및 가열시간(10, 15, 20, 23, 30 min)에 따른 중심합성실험계획으로 가열처리 하여 반응표면분석하였다. 그 결과, 가용성 고형분 함량의 경우 가열온도 및 가열시간이 증가할수록 감소하는 것으로 나타났으며 갈색도는 가별온도 및 가열 시간이 증가할수록 증가하는 것으로 나타났다. 또한 산성 다당체 함량, 총 폐놀성 화합물 함량도 가열온도 및 가열시간이 증가할수록 증가하는 것으로 나타났다. 가용성 고형분 함량은 가열온도 146.05$^{\circ}C$ 및 가열시간 18.16 min일 때 최대값 58$\%$로 예측되었으며, 조사포닌 함량은 160.00$^{\circ}C$ 및 가열시간 20.00 min일 때 64.40 mg/g의 최대값으로 예측되었다. 조사포닌 함량은 가열시간에 영향을 많이 받는 것으로 나타났으며, 가용성 고형분 함량, 산성다당체 및 총 페놀성 화합물 함량은 가열온도에 영향을 많이 받는 것으로 나타났다.

• 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.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1025-1030
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• 2009

It is known that the classical tuning formula for typical PID controllers in general provides unsatisfactory results for industrial plants where the time delay exceeds the dominant lag time. For this reason, alternative strategies have been studied in order to cope with this problem and the most popular scheme is the Smith Predictor(SP). In this paper, the dynamic model of a unit apartment in the district heating system, which is the control process effected by the dead-time, is developed, and the on/off room temperature control method with the SP simulate using Matlab-Simulink. The simulation results show that the SP works effectively in outdoor temperature variation.

• 한국조리학회지
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• 제14권3호
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• pp.210-222
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• 2008

This study showed that the brown stock, which is the base of demi-glace sauce, extracted by using a high pressure heating extractor is more advantageous than that extracted by the traditional extraction method for the mass production. We compared the former with the latter in terms of minerals and free amino acids. The results of this study are summarized as follows. When mineral contents were compared, the brown stock extracted by high.pressure heating extraction showed the tendency of increase in mineral contents in proportion to heating temperature and heating time, but, from extraction temperature of 140$^{\circ}C$, the contents of K, Mg, Na and P decreased with the increase of extraction time. In addition, mineral contents in the brown stock extracted by high-pressure heating extraction were generally lower than those in brown stock extracted by the traditional extraction method. This result was produced probably because materials were added repeatedly in the traditional method. Amino acids contents in brown stock according to the extraction methods were also examined. They increased with the increase in the number of extractions in the brown stock extracted by the traditional method, and those in the brown stock extracted using a high pressure heating extractor increased with the increase in heating temperature and extraction time. The results of this study are expected to be useful as a practical material for the mass production of brown stock products.

• 대한한의학회지
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• 제15권2호
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• pp.241-252
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• 1994

It is known that the pattern of combustion temperature can be classified into preheating, heating. retaining and cooling periods. In this experiment. the authors have studied the heating mechanism by the density of moxa material during the heating and retaining periods. The starting point. the point at which it begins to reach the maximum gradient temperature. the ending point of the heating period. and the ending point of the retaining period were measured in order to get effective stmulation by repetition of moxa-combustion. For the experiment. samples of 300mg. 400mg, and 500mg of moxa material were molded into conical molds with each 10mm in diameter and height resulting in the volume of $0.26cm^3$. The following results were obtained: The $300mg/0.26cm^3$ denstiy sample reached al1 points tested faster than the samples of $400mg/0.26cm^3$ and $500mg/0.26cm^3$ It dose not reveal any statistical differences between $400mg/0.26cm^3$ and $500mg/0.26cm^3$ in the ending point. the point at which it begins to reach the maximum gradient temperature of the heating period or the ending point of the reataining period The only difference shown was in the starting point of the heating period. According to the above results. it is concluded that the lower density moxa material reached each point of the the respective period faster than the high density moxa material.

• 한국기계가공학회지
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• 제21권2호
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• pp.94-100
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• 2022

A study was conducted to significantly increase the heat transfer area by simultaneously burying the excel pipe in the floor and wall of a container house, thereby greatly reducing the initial heating time. In addition, a small hot water boiler suitable for the heating load of a small container house with a maximum area of 6 m² was studied. A wall-mounted hot water boiler was developed as a result of the study. When a hot water boiler is installed outdoors for heating, heat radiation energy is lost in winter from the hot water boiler and hot water pipe due to the low temperature. We propose an approach through which the energy loss was greatly reduced and the temperature of hot water increased in proportion to the operating time. Moreover, as the mass flow rate of the hot water flowing inside the excel pipe increased, the temperature of the hot water decreased. The temperature of the wall and floor surfaces of the container house increased in proportion to the increase in the mass flow rate of hot water flowing inside the excel tube. Natural convection heat transfer was realized from the wall and floor surfaces of the container house, and the heat transfer area was increased by a factor of 3 with respect to heat transfer area limited to the floor by the existing hot water panel. As a result, the initial temperature increase rate was much higher because of the larger heat transfer area.

• Macromolecular Research
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• 제10권6호
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• pp.318-324
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• 2002

In this paper we have extensively studied what and how processing parameters for quasi-carbonization influence the breaking strength and modulus of resulting quasi-carbon fabrics that are prepared from stabilized PAN fabrics with a spun yarn texture. Seven processing parameters have been considered as follows: applied tension, final heat-treatment temperature, heating rate, heating step, holding time, cooling rate, and purging gas purity. The results indicate that optimal uses of applied tension, final heat-treatment temperature, heating rate, and heating step during quasi-carbonization process are primarily important to increase the tensile properties of quasi-carbon fabrics and holding time, cooling rate, and purging gas purity are less importantly contributed.

• 자원ㆍ환경경제연구
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• 제27권2호
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• pp.287-313
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• 2018

본 연구는 전력수요의 냉방 및 난방 수요를 측정하고 분석한다. 이를 위해 냉난방기온효과를 추정하고 이를 Chang et al. (2014)의 전력수요함수 모형에 적용하여 전력수요를 기본수요, 냉방수요 그리고 난방수요로 분해하였다. 1999년 1월부터 2016년 12월의 한국의 일반용과 주택용 전력수요를 분석한 결과, 난방수요의 증가율이 기본수요와 냉방수요의 증가율을 월등히 상회하였으며 특히 일반용에서 난방수요 증가가 두드러졌다. 평년기온으로 통제한 기온보정된 난방수요는 실현된 난방수요보다 상대적으로 '더' 증가하였고, 냉방수요는 반대로 기온보정된 수요가 실현된 수요에 비해서 '덜' 증가하였다. 본 논문은 전력수요 내의 냉방 및 난방수요를 측정할 뿐 아니라 경제주체들의 전력수요 변화 패턴을 확인했다는 점에 의의가 있으며, 추정 결과들은 향후 전력수요예측과 에너지수요관리 정책 수립에 도움을 줄 수 있을 것으로 기대된다.

• Journal of Biosystems Engineering
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• 제15권3호
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• pp.230-243
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• 1990

This study was conducted to investigate the possibility of application of an infrared drying to drying process for red pepper. The performance of seramic heaters and the variation of temperature and moisture content of red pepper were analyzed during an infrared drying of red peppers. Also, the quality of dried red pepper was analyzed. The following results were obtained from this study. 1. The surface temperature of infrared heaters and the rising time required for steady state were mainly affected by electrical power consumed. 2. The heat energy required for heating red pepper was proposed to be calculated by the equation in terms of enthalpy of air and net heat flux by infrared heater in a drying chamber. The statistical model for net heat flux was developed. 3. The performance of the infrared heater used for heating red pepper was much affected by the distance of radiation, and the difference of temperatures appeared between the radiated surface and the inside of red pepper. 4. Electrical capacity of the infrared heater had a significant effect on the heating of red pepper. However, the effect of shape of heater on heating was not significant. 5. The variation of temperature of red pepper largely appeared in the range of 30 to 60% (db) in moisture content. The temperature of red pepper was almost constant at low moisture content. 6. The temperature of red pepper and heating time had significant effects on the quality for radiant heating. 7. When the electrical capacity of infrared heater and the distance of radiation are carefully designed in a dryer with the insulated drying chamber, infrared drying might be very effective in red pepper drying.

• 한국식품영양학회지
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• 제12권6호
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• pp.569-574
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• 1999

Response surface methodology(RSM) was applied to determine the optimum heating conditions(tem-perature and time) for the inactivation of bacteria associated with food hygiene. Coefficients of determinations(R2) for the cell growth were 0.9155(P<0.05) in Pseudomonas aeruginosa 0.8997(P<0.05) in Escherichia coli 0.9690(P<0.01) in Salmonella typhimurium 0.9393(P<0.05) in Enterobacter aerogenes and 0.7905 in Vibrio parahaemolyticus. The growth of strains was significantly affected by the temperature and time and reaction to temperature was most closely correlated to the inhibition of growth. On the basis of superimposed contour maps of cell growth the optimum range of heating conditions were 55.62-6$0^{\circ}C$ and 19.25-30 min.