• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.199-202
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• 2003

우리나라 전체 시설원예 면적 52,135ha(2001년) 중 난방을 하고 있는 시설원예 면적은 12,710ha로서 약 24%정도를 차지하고 있다. 시설재배면적의 지역분포를 비교해 보면, 시설채소의 경우 중부 이북지역에 44%, 남부에 56%의 비율로 분포해 있으며, 시설화훼의 경우 중부 이북 58%, 남부 42%로서 난방비가 많이 소요되는 지역이라도 수도권을 중심으로 유통이나 지리적 면에서 유리한 지역에 시설재배면적이 많이 분포해 있다. (중략)

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.419-428
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• 2021

In order to develope a mobile-based greenhouse energy calculation program, firstly, the overall thermal transmittance of 10 types of major covers and 16 types of insulation materials were measured. In addition, to estimate the overall thermal transmittance when the cover and insulation materials were installed in double or triple layers, 24 combinations of double installations and 59 combinations of triple installations were measured using the hotbox. Also, the overall thermal transmittance value for a single material and the thermal resistance value were used to calculate the overall thermal transmittance value at the time of multi-layer installation of covering and insulating materials, and the linear regression equation was derived to correct the error with the measured values. As a result of developing the model for estimating thermal transmittance when installing multiple layers of coverings and insulating materials based on the value of overall thermal transmittance of a single-material, the model evaluation index was 0.90 (good when it is 0.5 or more), indicating that the estimated value was very close to the actual value. In addition, as a result of the on-site test, it was evaluated that the estimated heat saving rate was smaller than the actual value with a relative error of 2%. Based on these results, a mobile-based greenhouse energy calculation program was developed that was implemented as an HTML5 standard web-based mobile web application and was designed to work with various mobile device and PC browsers with N-Screen support. It had functions to provides the overall thermal transmittance(heating load coefficient) for each combination of greenhouse coverings and thermal insulation materials and to evaluate the energy consumption during a specific period of the target greenhouse. It was estimated that an energy-saving greenhouse design would be possible with the optimal selection of coverings and insulation materials according to the region and shape of the greenhouse.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.35-41
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• 2013

This study was conducted to provide data necessary for reducing the condensation on greenhouse covering in winter season. The variation of VPD (Vapor Pressure Deficit) and condensation flux was analyzed in experimental tomato greenhouse. VPD values in experimental plastic greenhouse were greater than 0.2 kPa of disease prevention threshold, and lower than 0.5 kPa of threshold for dehumidification. The surface temperature of inside covering was slightly higher than the average temperature of outside and above curtain, and changed according to outside temperature. The humidity above curtain was nearly 100% and good condition for condensation. The humidity below curtain was 75~90% and comparatively stable condition for growing. The condensation flux value in experimental greenhouse corresponded with result of Seginer and Kantz (1986).

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.189-198
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• 2009

This survey was conducted to investigate the situation of housing type in poultry farms in Korea. The number surveyed among the farm size over 30,000 heads was 1,965 farms. Poultry housing types of windowless, open sided, vinyl house type were 19.0, 47.7, 19.8%, respectively. Waterers of nipple, bell, and 8 feet trough used in smaller than 50,000 heads of poultry farm were 40.6, 11.3 and 42.8%, respectively. But the bigger farm in the farm size of over 100,000 heads used more nipple waterer. Feeders of disk, hopper and chain used in poultry farm were 54.5, 16.3, 15.8%, respectively. Manure collecting system of scraper and belt was 29.4, 71.5 %, respectively. Ventilation systems of natural ventilation, natural + mechanical ventilation, mechanical ventilation were 40.5, 39.8, 20.7%, respectively.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.763-769
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• 2018

In this research, in order to improve the heat retention of greenhouse, comparative analysis of the heat flux of the marketed multi-later insulating curtain was carried out. Experiments is conducted by fabricating a test apparatus for investigating the heat flux characteristics. The multi-later insulating curtain used for the experiment was compared using the P, N, S, U and T company, which are commercially available, and the heat flux due to temperature difference between the experimental apparatus and the outside was compared and analyzed. When the internal temperature of the experimental result is the maximum temperature $60^{\circ}C$, the heat flux of multi-later insulating curtain is T Co.($73.1W/m^2$) > S Co.($119.5W/m^2$) > U Co.($155W/m^2$) > N Co.($163.1W/m^2$) > P Co.($177.7W/m^2$). The heat flux means the quantity of heat passing through the unit time per unit area, and the higher the numerical value, the higher the quantity of heat passing through the multi-layer insulating curtain. This can be determined that high heat fluxes produce low heat resistance. Further, it has been found that the weight of the insulating curtain is largely unrelated to the heat insulating property, and the heat insulating curtain having a thickness containing a high internal air layer is excellent in the heat insulating property. In the future when manufacturing a heat insulating curtain, It is judged that it is desirable to manufacture a combination of heat insulating materials that contain a high internal air layer content and that can maintain the air layer even for long-term use while minimizing the volume.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.73-85
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• 2009

An investigation was conducted to get the basic data for establishing structural safety and environmental management of tomato greenhouses in Chungnam region. The contents of the investigation consisted of actual state of greenhouse structures and environmental control facilities. Most of greenhouses were arch type single-span plastic houses and they had too low height for growing tomatoes. Frameworks of multi-span greenhouses were suitable, but those of single-span were mostly insufficient. Every greenhouse had thermal curtain movable or covering fixed inside the greenhouse for energy saving, and heating facilities were mostly warm air heater. Irrigation facilities were mostly drip tube and controlled by manual operation or timer. Almost all of the greenhouses didn't install high level of environmental control facilities such as ventilator, air circulation fan, $CO_2$ fertilizer, insect screen, supplemental light, and cooling device.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.756-759
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• 2017

The productivity of cultivated crops in Korea is low compared to the Netherlands, which is an advanced agricultural country. In addition, modernization of facility and complex environmental control technology are needed to overcome poor growth and productivity deterioration caused by shortage of sunshine, abnormal temperature and high temperature due to abnormal climate. On the other hand, domestic facility horticulture complex environmental control is a level of machine automation that can check the internal situation of a green house with a cell phone and remotely operate a sprinkler, heat cover, curtain, ventilator, Therefore, this paper suggests the development of optimum environment control technology for facility horticulture based on the growth model and the cultivation technology knowledge base in order to realize the automation of optimal complex environment control and contribute to improvement of quality and productivity of cultivated crops.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.73-79
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• 2013

An experiment was conducted to study incidences of heat loss in greenhouse in Gyeongnam province using thermal imaging camera in order to determine ways minimizing greenhouse heat loss. Measurements of this work showed that temperature differences between two experiment zones before and after installation of thermal curtains were about $2.0{\sim}3.0^{\circ}C$ and $1.0{\sim}2.0^{\circ}C$ respectively. There was a high correlation between the temperature data measured using a thermal imaging camera and a temperature sensor. There was no serious difference among areas, but between places on the first and second floor with thermal curtains for heat insulation, there was a relatively larger heat loss on the first floor than the second floor. Then in general the greenhouse types had no particular bearing on this matter, there was a relatively large heat loss in the parts of side wall window, the gaps and the parts folded of horizontal thermal curtains, the gutter parts, and the gaps of thermal curtain in the side wall window and facade back side for heat insulation, aren't completely sealed. It was found that there was a substantial heat loss due to infiltration through cracks on covering material, doors, ventilating openings, roof gables and floors, in particular.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.428-436
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• 2012

This study aimed to develop the multi-span plastic greenhouse which is suitable for tomato cultivation and is safe against climatic disasters such as typhoon or heavy snow. The width and heights of eaves and ridge of newly developed tomato greenhouse are 7, 4.5 and 6.5 m, respectively. The width is the same but the eaves and ridge heights are 1.8 and 2 m higher than conventional 1-2 W greenhouses, respectively. Cross beam has been designed as a truss structure so it can sustain loads of tomato and equipment. Tomato greenhouse has been designed according to climatic disaster preventing design standard maintaining the high height. In other words, the material dimensions and interval of materials including column and rafter have been set to stand against $40m{\cdot}s^{-1}$ of wind and 40 cm of snow. Tomato greenhouse has been equipped with rack-pinion type roof vents which have been used in glass greenhouse in order to prevent excessive rise in air temperature. This vent type is different from that of 1-2 W type greenhouse which is made by rolling up and down the vinyl at upper part of column. Roof vents are installed at ridge, and thus external air inflow and natural ventilation are maximized. As the height increases, heating cost increase as well and, therefore, tomato greenhouse has been equipped with multi-layered thermal curtain, of which thermo-keeping is excellent, to prevent heat from escaping.

• Journal of Mushroom
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• v.14 no.2
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• pp.39-43
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• 2016

In this study, we observed differences in the fruit body genesis in with seasonal changes. The mushrooms generated different spines even when under same environmental conditions in equivalent growth chambers during different seasons. The growth chamber conditions were set at $18^{\circ}$, 1000 ppm CO and 95% humidity for uniform primordium formation. Following this, the humidity was reduced to 85% during growth and development. The characteristics of the fruit body were measured: yield (weight), length (size), hardness, and chromaticity. Each measure was relatively compared owing standard data for. We investigated the environmental factors to assess the cause of variation in fruit body. Change in temperature and humidity were especially focused on, apart from climate that can affect mushroom growth. It was observed that temperature and humidity both influence fruit body growth. Not the absolute value of the elevation, there was a change of climate which the temperature is lowered and lowered the humidity can be assumed that the changes in the environmental conditions inside the growth chamber the mushroom growth.