• Korean Journal of Agricultural Science
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• v.28 no.2
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• pp.99-107
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• 2001

It is difficult to install a ventilation window on the roof of single span greenhouses of arch shape. Investigation on the roof ventilation structures for those greenhouses was conducted. In small greenhouses with spans of 5 to 8 m, circular or chimney type ridge vents made of plastic were employed. In large greenhouses with spans of 12 to 18 m, even span roll-up ridge vents made of steel pipe were employed. The effect of roof ventilation was evaluated by comparative experiments between greenhouse installing ridge vents and having controlled side vents only. Roof ventilation contributed greatly to restraint of temperature rise and maintenance of uniform temperature distribution in greenhouses. And ventilation efficiency was analyzed by experiments on the opening and closing operation of the ridge and side vent. There were no temperature differences according to opening and closing sequence of ventilation window. But for greenhouse temperature control by ventilation, it is desirable to open side vents after ridge vents and to close ridge vents after side vents.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.334-342
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• 2016

In order to evaluate the modified installation methods of roof ventilation devices, derived from the previous experiment ('investigation into the optimum capacity of roof ventilation devices and their deployment'), the conventional and modified (improved) roof ventilation systems were installed in the single-span plastic greenhouse for growing oriental melons. The roof vents ($60{\varphi}$) and roof fans (maximum air capacity of $38m^3/min$) were installed in the spacing of 15m (FT, modified 'side vent+roof fan' ventilation) and 6m (TT, modified 'side vent+roof vent' ventilation) respectively on the roof of greenhouses for the modified roof ventilation treatments, and 20m (FC, conventional 'side vent+roof fan' ventilation) and 8m (TC, conventional 'side vent+roof vent' ventilation) for the conventional ones. The stem diameter, leaf blade lengh, petiole length, and leaf width were lower in the FT and TT treatments than those in the conventional treatments, FC and TC. Although the fruit weight and total yields were slightly lower in the FT and TT treatments, the marketable fruit ratio (%) were higher, as a result of increased fruiting ratio (%) in these treatments, than those of FC and TC. The marketable yields (kg/10a) in the FT and TT treatments were 8,391 kg/10a and 7,283 kg/10a, which were respectively 661 kg/10a and 487 kg/10a higher than those in the treatments of FC and TC. The modified installation methods of roof fan resulted in production of more female flowers and lower fruit drop ratio (%) compared to conventional meathods. In the treatment of the conventional ventilation with roof vent, the fruit weight, fruit length & width, and flesh thickness were higher than in other treatments, but there were no significant differences in the fruit width and flesh thickness among the treatments.

• 월간낙농육우
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• v.37 no.7
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• pp.114-117
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• 2017

하절기 목장의 축산시설 관리 포인트는 무엇일까? 우선 유우사는 개방식 축사이기 때문에 지붕의 재료에 따라 다르지만 햇빛과 바람 관리만 잘해도 우사환경은 개선되는데, 계절적으로 하절기로 접어들면서 소가 더위에 시달리며 산유량이 떨어지는 목장이 많아지고 있다. 따라서 농가에서 무조건 환기팬의 대수만 많이 설치하면 된다고 생각하여 환기팬을 추가적으로 많이 설치해주고 있는 실정이다. 그러나 환기는 지붕의 구조와 소의 사육단계 등을 근거로 환기량을 결정해야 한다. 특히 여름철은 우사내 습도 관리를 잘해주어야 소의 생산성과 사료효율을 최적화할 수 있다. 따라서 적절한 채광을 해주고 바람의 이용과 차단을 해준다면 소는 하절기에 시원함을 느끼고 청결을 유지하며 관리자의 노력도 최소화되는 환경을 만들 수 있다. 따라서 본고에서는 시설 및 환기개선을 통한 하절기 축사관리 방법에 대하여 알아보고자 한다.

• Journal of Animal Environmental Science
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• v.10 no.1
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• pp.23-28
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• 2004

This study was conducted to improve a ventilation system on the enclosed farrowing-nursery pig house in Korean swine facilities. This survey ventilation system types four major structures. The first structure has planer slot inlet, where air comes in, and these are placed outside the wall under the eave. Then the air from the pig house flows out through the chimney outlet operated by an exhaust fan(V1). The second structure has an air input through the perforated ceiling inlet, then the air from the pig house flows out through the chimney outlet operated by an exhaust fan(V2). Through the circular duct inlet placed inside the juncture of the entry wall, air also comes in(third structure). Then, air from the pig house flows out through the chimney outlet operated by an exhaust fan(V3), Similarly, air comes in through the circular duct inlet placed inside the juncture of the entry wall, but air from the pig house flows out through the side wall by an exhaust fan(V4). Temperature, relative humidity, air velocity and ammonia concentration(NH$_3$) were measured in the interior farrowing-nursery pig house during winter. The results were as follows; Interior temperature at the pig house was not remarkably different in all ventilation systems. The V4 system had low area air velocity, and this was better than other systems. It also had a lower ammonia concentration than other systems. V3 and V4 systems had stable airflow patterns, better than other systems. Therefore, it is suggested that the V3 and V4 ventilation system be applied in the enclosed farrowing-nursery pig house in winter.

• Journal of architectural history
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• v.26 no.4
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• pp.7-17
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• 2017

Suncheon Songgwangsa has unique ventilation roofs. In the meantime, these roofs have been known as a characteristic element of Songgwangsa architecture and a unique element of Korean traditional architecture. I would like to review the installation time of the ventilation roof and check the installation time through Songgwangsa's records and photographs. According to the results of this study, it was confirmed that the ventilation roofs installed in various buildings including the temple of Songgwangsa were installed between the 1920s and 1930s. This can be summarized by comparing the history of Songgwangsa and the history of each building of Songgwangsa by comparing the paintings of Songgwangsa in 1886 and 1915 with the photographs of 1920s and Songgwangsa in the 1930s. It is a matter of further study whether the installation of the ventilation roof of Songgwangsa Temple is influenced by the Japanese occupation period.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.9-18
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• 1999

Natural ventilation in a four and one-half span, double polyethylene commercial greenhouse was investigated with actual data collected at Quailcrest Farm near Wooster, Ohio. Moreover, a computational fluid dynamics (CFD) numerical technique, FLUENT V4.3, was used to predict natural ventilation rates, thermal conditions, and airflow distributions in the greenhouse. The collected climate data showed that the multi-span greenhouse was well ventilated by the natural ventilation system during the typical summer weather conditions. The maximum recorded air temperature difference between inside and outside the greenhouse was 3.5$^{\circ}C$ during the hottest (34.7$^{\circ}C$) recorded sunny day; the air temperatures in the greenhouse were very uniform with the maximum temperature difference between six widely dispersed locations being only 1.7$^{\circ}C$. The CFD models predicted that air exchange rates were as high as 0.9 volume per minute (A.C. .min$^{-1}$ ) with 2.5m.s$^{-1}$ winds from the west as designed.

• 월간낙농육우
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• v.36 no.3
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• pp.146-150
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• 2016

봄맞이를 위한 목장의 축산 환경 관리 및 점검 포인트는 무엇일까? 우선 유우사는 대부분 개방식 축사이기 때문에 햇빛과 바람(공기) 관리만 잘해도 우사 환경은 개선되는데, 계절적으로 봄철로 접어들면서 겨울철 질퍽해진 축사바닥 및 환기를 조절해주어야 하는 시점에 접어드는 시기이다. 우사환경을 개선하기 위한 포인트는 첫째, 지붕 구조(재료)의 구성방법을 파악해 보고, 둘째, 환기방법을 점검해 보아야 한다. 따라서 본 원고에서는 시설 및 환기개선을 통하여 봄철만 아니라 사계절을 위한 축사 환경관리 방법에 대하여 알아보고자 한다.

• KOREAN POULTRY JOURNAL
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• v.36 no.6 s.416
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• pp.96-99
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• 2004

사계절이 뚜렷한 국내에서는 여름철 혹서기 사양관리를 하는 방법에 따라 산란율이나 폐사계의 발생빈도가 확연히 차이가 날 수 있다. 이러한 까닭에 기존계사에 비해 단열 및 환기문제에 있어서 보다 효과적인 무창계사라는 현대식 계사가 최근 강조되고 있는 것이다. 그러나 현재 전체 계사의 과반수 이상이 단열이 엉성하고, 완전 자연환기에 의존하는 계사는 물론 적절한 지붕단열, 일부 기계식 환기를 도입한 절충형 계사에서 사육되고 있으므로 이번 여름을 맞이하여 나름대로 대책을 세울 필요가 있다. 특히 지구 온난화 등의 환경적 요인 등을 고려할 때 해가 거듭될수록 여름은 과거 못지않은 수준일 것이라 예상되기 때문이다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.1
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• pp.17-23
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• 2018

A fire simulation was performed to analyze the temperature and smoke exhaust performance of roof vents of the arcade traditional market by comparing a basic model (Case A) and an improvement model (Case B~Case E). Temperature analysis by heat showed a low temperature distribution because Case E discharged smoke in both directions of length compared to other cases. However, the effect of heat by life safety standards was satisfied. The smoke exhaust analysis by smoke showed the highest performance because Case C was exhausted to 1 m on both sides of length.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.78-82
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• 2011

Ventilation rates, inside and outside weather data were measured in a arch-shape single-span plastic greenhouse growing tomatoes. On the roof of the experimental greenhouse, round windows which have a diameter of 0.6 m were installed at intervals of 8m. It showed that the number of air changes in this greenhouse were average 0.17 volumes per minute and in the range of 0.02 to 0.32 volumes per minute. These air changes are insufficient to meet the recommended ventilation rate for commercial greenhouses, and it is estimated that interval of 6 m is appropriate for spring or fall season. For summer season, it is necessary to narrow the space or to enlarge the open area of roof windows. Using the heat balance model, the evapotranspiration coefficients of greenhouse tomatoes were estimated from experimental ventilation data, overall heat transfer and solar radiation. It showed that the evapotranspiration coefficients were average 0.62 and in the 0.39 to 0.85 range. We suggest applying 0.6 as the evapotranspiration coefficient in design of ventilation for the single-span tomato greenhouses.