• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.89-98
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• 1993

The purpose of this study was to investigate crop growth responses under various rain shelters which were devised to improve the indoor environment in summer season. For developing the proper type of rain shelter, the improved rain shelters with the roof of saw - tooth type(saw-tooth type) and 3 span-arch type(improved arch type) were compared with the conventional one with the roof of single arch type(conventional arch type) and no rain shelter (open field ). The results were summarized as follows ; 1. The air temperature in the improved arch type was 4$^{\circ}C$ and 1$^{\circ}C$ lower than those in the conventional arch type and the saw - tooth type, respectively. 2. The air temperature drop by the evaporative cooling + improved drainage was 1.3$^{\circ}C$ which was 0.9$^{\circ}C$lower than that by the improved drainage only. 3. The effect of labour saving in the saw-tooth type was superior to any other type because its frames were used as props and the labour for ventilation was not needed. 4. The highest marketable yield of tomato was 4,897kg/10a in the improved arch type and the total leaf areas which related to photosynthesis was the largest in the saw - tooth type. 5. The improved arch type was proved to be proper to raise yield potential. The effect of the underground environment treatment on the quality and quantity of vegetable showed to be outstanding in the saw- tooth type with the evaporative cooling + improved drainage, and in the improved and conventional arch type with the trickle improved drainage. 6. In conclusion, the saw - tooth type and the improved arch type were proved to be labour saving rain shelters and the indoor environments in both types were better than that in the conventional arch type.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.185-191
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• 2009

The construction of experimental greenhouses, operating test, and analysis on variation of different environment factors were conducted to provide fundamental data for design of Korean style air-inflated double-layer plastic greenhouse. The development of technology of attaching plastic to the structure and fasteners to be able to keep airtight was required in order to maintain proper static pressure in air space of double layer coverings. The insulation effect of air inflated greenhouse was better than conventional type. The temperature of arch type roof was greater about $2^{\circ}C$ than peach type roof in air inflated greenhouse. It was recommended that the plastic should be attached at the edges without clearance length in order to ease installation and raise airtightness of double layer coverings. The transmittance of arch type roof was greater than peach type in air inflated one span greenhouse. The transmittance of air inflated greenhouse was greater than conventional type due to frame ratio and distance between double layers in three span greenhouse. The condensation occurred on conventional type greenhouse was more than air inflated type. It was required to examine for a long time in order to analyze it quantitatively.

• 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.