• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.478-486
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• 1993

For satisfactory greenhouse culture, environmental factors must be kept in proper conditions. Therefore, it is important to know relations between environmental conditions and greenhouse systems. In this study, the environment variations and distributions in different types of greenhouses were measured and analyzed. The elements of environment analyzed were temperature , relative humidity, illumination, carbon dioxide and wind velocity. The analyzed greenhouse types were three different types. One of them, A type, was propagation model type by government and the other one, B type, was multiple continuous arches type which was made by farmers himself. The last one, C type, was single arch type which has no environment control system without manual temperature keeping method. The results of this study can be used for reasonable greenhouse environments managements and control.

• Korean Institute of Interior Design Journal
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• v.18 no.6
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• pp.221-228
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• 2009

Recently severity of ecological adaptation and climatic change due to global warming grows larger. According to the fourth report of IPCC in 2007, emission quantity of the earth greenhouse gas(GHGs) generated by activity of mankind increased with 80% since 1970. And it is forecasted that worldwide greenhouse gas will be increased with 25~90%(corresponding to $CO_2$) between 2000 and 2030. This increment of greenhouse gas($CO_2$) is expected to raise average temperature of the earth with the maximum $6.4^{\circ}C$, and sea surface with 59cm in 2090. Like this, destruction of environment by greenhouse gas is regarded as universal problem threatening the existence, not only the problem of one nation. Consequently, systematic correspondence to the global warming at the aspect of energy consumption is also needed in Korea. From the analysis result of 'Statistics of Energy Consumption' published by Green Korea in 2007, energy consumption increment of domestic universities was higher as many as 3.7 times than 22.5% of the whole energy consumption increment in our country. This says to be the direct example which shows that universities are huge sources of greenhouse gas emission. New constructing and enlarging buildings of each universities within campus are the most major reason for such a large increment of energy consumption in universities. The opinion that the possibility of causing energy waste and efficiency reduction is raised by increased buildings of universities has been propounded. That is, universities should make concrete goal and the plan for reducing emission of green house gas against climatic change, and should practice. Accordingly, there is the meaning that 2 aspects of environment-friendly design characteristics, that is application of energy utilizing technology, material usage of energy efficiency-side and environment-side, and introduction of natural element in the environmental aspect, were analyzed for facilities of university campus designed in environment-friendly point of view from initial stage of plan, and direction of environment-friendly design of university facilities in the future was groped in order to grasp environment-friendly design tendency of internal and external University facilities based on this analysis of this paper.

• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.10-14
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• 2001

The cooling effect of a fog cooling system has a close relationship to air flow and relative humidity in the greenhouse. From the VETH chart for cooling design, a cooling efficiency can be improved by means of increasing the air exchange rate and the amount of sprayed water. In the no shading experimental greenhouse by time control, when average air exchange rate was 0.77 times.min$^{-1}$ and spray water amount was 2,009g, inside temperature of the greenhouse was 31$^{\circ}C$ that was almost close to outside temperature and cooling efficiency was 82%. When average air exchange rate was close to temperature of the greenhouse that was no cooling and 70% shading greenhouse environment. When average air exchange rate was 2.59times.min$^{-1}$ , spray water amount was 2,009g and shading rate was 70%, inside relative humidity of the greenhouse was increased was 2,009 g and shading rate was 70%, inside relative humidity of the greenhouse was increased, but temperature was not decreased. When average air exchange rate was 2.33 times.min$^{-1}$ and spray water amount was 2,009g, inside temperature was 31.4 and at that time maximum wind speed at the air inlet of greenhouse was 1.9m.s$^{-1}$ . Since time controller sprayed amount of constant water at a given interval, some of sprayed water remained not to be evaporated, which increased relative humidity and decreased cooling efficiency. Because the shading screen prevented air flow in the greenhouse, it also caused the evaporation efficiency to be decreased. In order to increase cooling efficiency, it was necessary to study on controling by relative humidity and air circulation in the greenhouse.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.1-7
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• 2006

This study was conducted to develop a system and an control algorithm for control the environment of a plant factory. The greenhouse control system for environmental control was largely composed of a computer and a PLC. The screen of control program was composed of a greenhouse figure which was included machinery and equipments for greenhouse, the graph of environmental factors of inside greenhouse and the image of greenhouse. In order to reduce temperature change, the operation time of ventilation window was changed by 3 stage according to difference between a target and present temperature. When is heating, a temperature variation was shown to be $16.7{\pm}0.8^{\circ}C$. When is cooling, a temperature variation was shown to be $23.1{\pm}0.6^{\circ}C$. When is humidifing, a humidity variation was shown to be $39.3{\pm}1.6^{\circ}C$ %RH. An environmental control system and a control algorithm were proved that it was shown a good performance in a control accuracy. So a computer control system should be adapted to a control system of a greenhouse and a plant factory.

• Solar Energy
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• v.6 no.2
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• pp.22-32
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• 1986

This study was carried out to analyze solar radiation in plastic greenhouse which is covered with polyethylene or polyvinyl chrolide film. A computer model for solar radiation analysis in the plastic greenhouse was developed and solar gain factors for E-W and N-S oriented plastic greenhouse in the greenhouse farming area during winter were investigated. Solar gain factors for E-W plastic greenhouse were 60 to 75 percent which were 10 to 15 percent higher than those for N-S plastic greenhouse from November to January. However, the values were apparently decreased in February and reversed in March, showing 3 to 5 percent higher in E-W plastic greenhouse. About 67 to 72 percent of the total solar radiation was attributed to the south-directed wall and roof for the E-W plastic greenhouse and about 30 percent through walls and 60 percent through roofs for the N-S plastic greenhouse.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.230-236
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• 1998

Thermal environment of greenhouse was investigated by thermo-tracer in this study. The Thermo-tracer is a high-sensitivity infrared thermometer of non-contact type. The infrared energy emitted from the measured object is converted into an electrical signal by the detector(HgCdTe) and display as a color or black & white thermal image by way of optical scanning, The experiment was conducted for Venlo-type greenhouse with pad & fan system. The temperature difference between measured by Thermo-trace and measured by HOBO sensor is maximum 0.8$^{\circ}C$. Thermo-trace is possible to use for the thermal environment analysis and diagnosis of a cooling and heating system of greenhouse.

• Journal of Biosystems Engineering
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• v.23 no.2
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• pp.147-156
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• 1998

It is desirable to use the renewable energy for the greenhouse heating in winter season, it make possible not only to save fossil fuel and conserve green environment but also to promote the quality of agricultural products and reduce the agricultural production cost. In this study the heat pump - PCM latent heat storage system has been developed to use the natural energy as much as possible for the thermal environment control of greenhouse. The coefficient of performance (COP) of the heat pump system was 3~4 with the ambient temperature ranging from 8$^{\circ}C$ to -8$^{\circ}C$, and greenhouse heating effect of the heat pump-PCM latent heat storage system on the basis of the ambient temperature was about 12-15$^{\circ}C$.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.6
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• pp.912-921
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• 2006

This study examines greenhouse gas reduction potentials in cement manufacturing industry of Korea. An energy system model in the MARKAL (MARKet ALlocation) modeling framework was used in order to identify appropriate energy technologies and to quantify their possible implications In terms of greenhouse gas reduction. The model is characterized as mathematical tool for the long term energy system analysis provides an useful informations on technical assessment. Four scenarios are developed that covers the ti me span from 2000 to 2020. Being technology as a fundamental driving factor of the evolution of energy systems, it is essential to study the basic mechanisms of technological change and its role in developing more efficient, productive and clean energy systems. For this reasons, the learning curves on technologies for greenhouse gas reduction is specially considered. The analysis in this study shows that it is not easy to mitigate greenhouse gas with low cost in cement manufacturing industry under the current cap and trade method of Kyoto protocol.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.418-423
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• 1999

This study was performed to find an efficient method to overcome extremely high temperature within greehhouse in summer season. The actual states of practical use for greenhouse in hot summer season were investigated. About 21.6% of the investigated greenhouse farms were no cultivation, and most greenhouse farms were cultivating under the very inferior environment . To examine thermal enviornment of greenhouse according to cooling or assistant cooling , greenhouses were treated with natural ventilation, shading, roof sprinkling , and evaporative cooling with air cool fan. Shading and operating air col fan showed a drop in temperature of 3.8∼4.2$^{\circ}C$ as compared with natural ventilation, and most greenhouse air temperatures were maintained below 35$^{\circ}C$.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.1101-1116
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• 1996

It is desirable to use the renewable energy for the greenhouse heating in winter season, it makes possible not only to save fossil fuel and conserve green farm environment but also to promote the quality of agricultural products and reduce the agricultural production cost. In this study the heat pump system was developed to use the natural energy as thermal energy resource for the thermal environment control of the greenhouse.