• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.40-45
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• 2013

Satellite's infrared detector shall be calibrated under thermal vacuum environment using a reference black body before a launch. The full aperture black body (FABB) as an infrared calibration reference shall be composed of vacuum compatible materials and temperature controlled from $-40^{\circ}C$ to $+40^{\circ}C$ with emissivity higher than 0.95. The temperature homogeneity over the central 80 % area of the FABB front surface shall be better than 2 K. The FABB designed by thermal and flow analysis was $1m{\times}1m{\times}8mm$ copper plate on which black painted aluminum honeycomb core was attached. Copper tubes were welded on the opposite side of the honeycomb core to allow temperature regulated gaseous nitrogen to flow through them. By the FABB validation test, the temperature homogeneity was observed around 1 K using 20 PT100 sensors and modified COTS infrared camera. The emissivity value was 0.975 at $40^{\circ}C$ under atmospheric pressure.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.125-135
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• 1999

In this paper, the thermal characteristics in plastic greenhouses with heating systems of electric power, hot air, and non-heating are measured and analyzed by field tests. From these tests, we were able to estimate the heating efficiency and quantitatively evaluate the characteristics of indoor thermal distributions of the particular heating system in greenhouses. The heating system of electric power was ineffective to reduce the difference of thermal distribution in the vertical direction. The hot air heating system also does not properly reduce the serious temperature fluctuation by time. By removing the above problems, these data will be utilized effectively to design better thermal environment in greenhouses.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.349-354
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• 2013

This study examined a technique for cooling root zone aimed at lowering substrate temperature for sweet pepper (Capsicum annum L. 'Orange glory') cultivation in coir substrate hydroponics during hot season, from the $16^{th}$ of July to $15^{th}$ of October in 2012. The root zone cooling technique was applied by using an air duct (${\varnothing}12$ cm, hole size 0.1 mm) to blow cool air between two slabs during night (5p.m. to 3a.m.). Between the $23^{rd}$ of July and $31^{st}$ of August (hot temperature period), average daily substrate temperature was $24.7^{\circ}C$ under the root zone cooling, whereas it was $28.2^{\circ}C$ under condition of no cooling (control). In sunny day (600~700 W $m^{-2}{\cdot}s^{-1}$), average substrate temperatures during the day (6a.m. to 8p.m.) and night (8p.m. to 6a.m.) were lower about $1.7^{\circ}C$ and $3.3^{\circ}C$, respectively, under the cooling treatment, compared to that of control. The degree of temperature reduction in the substrate was averagely $0.5^{\circ}C$ per hour under the cooling treatment during 6p.m. to 8p.m.; however, there was no decrease in the temperature under the control. The temperature difference between the cooling and control treatments was $1.3^{\circ}C$ and $0.6^{\circ}C$ in the upper and lower part of the slab, respectively. During the hot temperature period, about 32.5% reduction in the substrate temperature was observed under the cooling treatment, compared to the control. Photosynthesis, transpiration rate, and leaf water potential of plants grown under the cooling treatment were significantly higher than those under the control. The first flowering date in the cooling was faster about 4 days than in the control. Also, the number of fruits was significantly higher than that in the control. No differences in plant height, stem thickness, number of internode, and leaf width were found between the plants grown under the cooling and control, except for the leaf length with a shorter length under the cooling treatment. However, root zone cooling influenced negligibly on eliminating delay in fruiting caused by excessively higher air temperature (> $28^{\circ}C$), although the substrate temperature was reduced by $3^{\circ}C$ to $5.6^{\circ}C$. These results suggest that the technique of lowering substrate temperature by using air-duct blow needs to be incorporated into the lowering growing temperature system for growth and fruit set of health paprika.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.303-311
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• 1996

The microflora changes of 10 water-controled treatments combined with livestock manures(pig, chicken) and bulking agents(sawdust, paper sludge) were investigated. The B/F values of the P-1 and C-1(65%, $H_2O$) treatments were 3571 and 5400 respectively, but those of the P-4 and C-4(50%, $H_2O$) treatments showed very low values, 667 and 334, respectively. The B/F values tended to increase with higher water content of the treatments. In the composting processes, the successions of microflora, adapting the compost environments, took place via fluctuating temperature. In the high temperature period, the numbers of mesophilic bacteria and fungi decreased, but that of the spore forming bacteria increased. However, the number of mesophilic bacteria inereased during the cold period. The B/F values of compost ranged 25-300, which indicates a decrease in the quantity of bacteria. The time required for the temperature of compost to reach $60^{\circ}C$ showed different patterns. There was no pathogenic microorganism in the treatments which reached a high temperature in a short period of time, but, in the treatments which reached a high temperature over a Long period of time, the pathgenic microorganism was not still alive.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.117-117
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• 2010

석탄 가스화에서 유도된 합성가스는 합성반응 공정을 통하여 합성석유, 메탄올(& DME), 합성천연가스(SNG) 등의 다양한 화학원료를 제조할 수 있어 이의 활용이 점차적으로 확대될 것이다. 이 중 SNG 공정의 경우, 석탄가스화기에서 생산된 합성가스는 집진, 탈황, 수성가스전환($H_2$/CO 비를 조절), $CO_2$ 제거 등의 공정을 거쳐 메탄화 반응기로 유도되는데, 메탄화 반응에서 $CO_2$가 반응에 참여하면 탄소포집 및 저장(CCS)의 부담을 크게 줄일 수 있어 이에 대한 관심이 커지고 있다. 특히, 상업용으로 활용되고 있는 단열반응기를 직렬로 연결할 경우, 메탄화반응의 발열로 인한 반응기내의 온도 상승으로 $CO_2$가 생성되는데 이후의 2차 또는 3차의 단열반응기에서 $CO_2$ 수소화반응이 진행되면 최종 생성물인 메탄의 수율이 증가하며, 뿐만아니라 생성물 중 포함된 수소의 농도를 낮출 수 있는 장점을 가지게 된다. 따라서, 본 연구에서는 Ni계 촉매를 사용하여 풍부한 $H_2$ 분위기에서 Fe를 첨가하여 이의 함량이 $CO_2$ 수소화반응의 탄소 전환율과 생성되는 메탄의 수율에 미치는 영향을 고찰하였다.

• 월간 기계설비
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• no.2 s.187
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• pp.87-90
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• 2006

제15회 동아전람-MBC건축박람회가 지난 2월 2일부터 6일까지 5일간 서울무역전시장에서 개최되었다. 이번 전시회는 건축자재 및 인테리어, 가구, 조립식 주택 등이 출품되었는데 설비부문에는 난방부자재 및 욕실용품이 주를 이루었다. 특히 베란다 확장에 따른 리모델링의 주류를 타고 필름난방이 대거 출품되었다. 이밖에 온도조절기, 폐수를 재활용하는 자원절약의 양변기 등도 선보였다. 다음은 이번 전시회에 출품된 설비부문 자재중 눈여겨 볼만한 제품이다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.278-279
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• 2002

소각시설에서 다이옥신 배출문제가 사회문제화 되면서 대부분의 소각시설이 소석회 슬러리 분무의 반건식세정기와 백필터가 연결된 공정에 분말활성탄을 분무하는 시스템으로 운영하고 있다 원래, 다이옥신이 사회문제화 되기 이전부터 소석회 슬러리 분무의 반건식 세정기가 소각시설에서 사용되었는데 이는 주로 산성가스 제거 및 백필터 보호차원의 온도조절기능이었다. 백필터의 경우도 전기집진기와 더불어 먼지를 제거하는 기능을 담당하는 방지시설이었다. (중략)

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.36-41
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• 2001

This experiment was carried out to investigate temperature distribution in the double layer plastic greenhouse and chilling injury to watermelons grown during a cold season. Temperatures on eastern and western sides were about 6.2% and 14.7%, respectively, lower than that of central section in a south-north oriented greenhouse. Daily mean temperature in the northern part was about 1-2$^{\circ}C$ higher than that in the southern part of the greenhouse. In terms of vertical temperature distribution inside the greenhouse, temperature at ground surface was approximately 1$^{\circ}C$ lower during the day and 0.5$^{\circ}C$ higher during the night than that in the upper part, 2m from the ground surface. Leaf mould medium kept higher ground temperatures as compared to sandy soil, red clay soil, and in the northern and southern sides as compared to the central part of the greenhouse. A symptom of chilling injury on leaves was upward curling, followed by chlorosis and necrosis. A severe symptom of chilling injury to plants was the breakdown of vascular bundles. Root growth was more susceptible than stem or leaf growth to low temperatures. At 3$0^{\circ}C$, main and lateral roots grew vigorously, while lateral root growth was inhibited at 22$^{\circ}C$ and root growth was stopped at 14$^{\circ}C$ and 6$^{\circ}C$. Small and puffy fruits with dark green surface were produced at low temperatures. In cold season cultivation of watermelons, it is suggested that plants be transplanted in the central part and train to sides of the greenhouse in order to reduced chilling injuries.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.793-799
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• 2016

This study examined Platanus orientalis and Ulmus davidiana planted in downtown parks to identify the correlations among microclimatic factors such as temperature in the crown, air flow, and wind speed. For the field survey, measurements were taken at 1 hour intervals from 09:00 am to 06:00 pm in August. For the measurement of microclimatic factors, data on temperature, light intensity, air flow, and wind speed were collected using a quantum sensor (PAR Quantum Sensor SKP215), a precision thermometer (Pt1000-Sensor), and a combination anemometer (1467 G4 & HG4). The results of the analysis demonstrated that both Platanus orientalis and Ulmus davidiana, showed a greater cooling effect inside the crown as compared with the outside temperature. The cooling effect inside the crown was more evident with air flow and wind speed factors. With relation to wind, the inner temperature of the crown of Platanus orientalis decreased due to air flow while that of Ulmus davidiana decreased due to wind speed. With no wind, the average variation in temperature inside the crown was $-0.9^{\circ}C$ for Ulmus davidiana and $-0.958^{\circ}C$ for Platanus orientalis, indicating that Platanus orientalis was relatively more effective in lowering the temperature of the planting space than Ulmus davidiana. This study is significant because it shows that different tree species have different effects on the microclimate and that factors affecting the formation of the microclimate of trees may vary with species. Further studies on species other than broad leaf trees, such as evergreen trees and shrubs, are required in order to plan the distribution of landscaping trees that are effective in regulating the microclimate within urban green spaces.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04a
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• pp.43-43
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• 1999

98년말 동일제지에 도입 설치된 Condebelt 설비는 세계 최초의 대형생산설비로 국제적 인 관심을 모으고 있다. 이러한 첨단 Condebelt 기술의 국산화를 위해서는 국내 원료 특성 에 적합하도록 공정최적화가 요청된다. 본 연구에서는 KOCC를 원료로 이용한 라이너지를 C Conde belt를 이용하여 생산할 경우 주요 공정변수에 따른 물성 변화를 평가하고, 이를 통하 여 Condebelt 공정을 최적화하고자 실험실용 파일로트 건조기를 이용하여 Condebelt 공정의 주요 변수가 지질에 미치는 영향을 검토하였다. 실험용 Condebelt 건조장치의 상부플레이트는 18WC까지, 하부플레이트는 냉각수를 이용 하여 40-80'C까지 조절이 가능하도록 설계하였으며, 유압을 이용하여 압체 압력과 시간을 변화시킬 수 있도록 하였다. 구축된 실험장치를 이용하여 Conde belt 공정의 주요 변수인 온도, 압력, 압체시간, 유입 지필의 건조도 변화에 따른 라이너지의 물성 변화를 평가하고 이를 실린더 건조된 종이의 물성과 비교하였다. 그 결과 본 연구에서 검토된 모든 건조조건에서 Conde belt 건조된 종이가 실린더 건조 된 종이보다 높은 강도를 나타내었으며, 투기저항성과 광택도 역시 향상되었다. 투기저항성 과 광택도는 강도적 성질과 달리 유입지 건조도가 높을수록, 상부플레이트의 온도가 높을수 록 그 효과가 저하되었다. 일반적으로 KOCC를 원료로한 라이너지를 Conde belt로 제조할 경우 상부 고온챔버의 온도를 160'C, 압체압력을 5 bar로 조절하는 것이 가장 좋을 것으로 판단되었다. 원료펄프의 조성에 따른 Condebelt 공정의 건조효과를 연구한 결과 모든 펄프에서 공히 C Condebelt 건조방법이 실린더 건조방법에 비하여 물성 향상 효과가 있는 것으로 나타났으 며, 그 효과는 펼프의 리그닌 함량이 높을수록 크게 나타났다. 또 Condebelt의 물성개선 특 성을 이용한 원료비 절감 가능성을 평가하기 위해 AOCC와 KOCC를 이용하여 단층지와 이 층지를 제조하고 물성을 비교평가하였다. 그 결과 Condebelt를 이용하면 KOCC의 비율을 증가시키더라도 AOCC만을 이용하여 실린더 건조한 종이보다 우수한 물성을 얻을 수 있었다. 이러한 연구를 통하여 Condebelt 공정이 국내 저급원료로 제조된 종이의 강도 저하를 극복할 수 있는 기술임을 확인하였다.