• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.145-152
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• 2011

In order to heat greenhouse nearby river channel, riverbank filtration water source heat pump was developed for getting plenty of heat flux from geothermal energy. Recharging well, thermal storage tank with separating insulation plate and filtering tank for eliminating iron, manganese were mainly developed for making the coefficient of performance (COP) of heat pump higher. Heating system using riverbank filtration water source heat pump was installed at a paprika greenhouse in the Jinju region where a single fold of vinyl cover and 2 layers of horizontal thermal curtain were installed as a part of temperature keeping and heat insulation with a greenhouse area of 3,185 $m^2$. 320,000 kcal/h was supplied for performing a site application tests. A greenhouse heating test was performed from Feb. 1, 2011 to Apr. 30, 2011. As the result of that, COPh of the heat pump was measured in the range of 4.0~4.5, while COPS of the system was represented as 2.9~3.3. COP measured of the heat pump was very good and well responded to indoor heating temperature of the environment control system of a greenhouse.

• 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.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.286-294
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• 2021

The International Maritime Organization (IMO) has been seeking measures to prevent climate change caused by shipping and actively discussing the initial strategy of reducing ship greenhouse gas emissions adopted in 2018. Member states are proposing various reduction measures in the IMO's 5th International Working Group on the Reduction of Greenhouse-gas emissions. However, each member country's method of measuring impact assessment differs, making it impossible to objectively compare impact assessment by country. As such, various measures have been proposed by each country to reduce greenhouse gas emissions, and it is necessary to determine a standard impact assessment measurement method that can be applied to all countries before 2023, when IMO's greenhouse gas reduction strategy is implemented. Therefore, this study seeks to develop detailed guidelines for impact assessment to objectively compare the impact assessment results of ships' greenhouse gas reduction measures. Drawing detailed guidelines that can compare the effectiveness of each country's reduction strategies will enable the IMO leading marine environment GHG reduction.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.11 no.2
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• pp.39-45
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• 2012

In recent years the USN(Ubiquitous Sensor Networks) technology has been applied in the greenhouse in order to control temperature and humidity automatically. In this paper, we proposed a control algorithm using feedback linearization techniques based on a mathematical model for temperature and humidity environment. Especially, Control algorithm is presented to the operation of the ventilator affecting on the temperature and humidity system at the same time. The System has been designed taking into account the disturbance(External temperature, soil temperature, external humidity, solar radiation and wind). In conclusion, I will present a way to control multiple actuator through simulations. The proposed control algorithm is validated using the Matlab/Simulink tools.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.340-345
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• 2000

This study was carried out to analyze the light and thermal environment in model greenhouse using infrared absorption film as shading screen and to compare with the case of no shading and using general shading screen such as aluminum foil-backed film, black polyethylene film and thermal blanket. PPFD(photosynthetic photon flux density) of inside the model greenhouse under infrared absorption film was increased by 22% than under general shading screen on the average. And temperature of inside air under infrared absorption film was 2$^{\circ}C$ lower than under general shading screen on the average. So, it is expected that infrared absorption film is useful as shading screen.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.126-129
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• 1999

Natural ventilation is achieved by air exchanges through multiple openings due to natural pressure variations inside and outside the greenhouse. Wind is the primary driving force making natural ventilation systems very difficult to design properly because of variations in wind velocity and direction. The optimization of these systems for acceptable climate control requires a thorough knowledge of the airflow rates and patterns as related to weather conditions and greenhouse structural details. (omitted)

• Journal of Bio-Environment Control
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• v.31 no.2
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• pp.79-89
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• 2022

With the wide use of greenhouses, the working hours have been increasing inside the greenhouse for workers. In the closed ventilated greenhouse, the internal environment has less affected to external weather during making a suitable temperature for crop growth. Greenhouse workers are exposed to organic dust including soil dust, pollen, pesticide residues, microorganisms during tillage process, soil grading, fertilizing, and harvesting operations. Therefore, the health status and working environment exposed to workers should be considered inside the greenhouse. It is necessary to secure basic data on particulate matter (PM) concentrations in order to set up dust reduction and health safety plans. To understand the PM concentration of working environment in greenhouse, the PM concnentrations were monitored in the cut-rose and Hallabong greenhouses in terms of PM size, working type, and working period. Compare to no-work (move) period, a significant increase in PM concentration was found during tillage operation in Hallabong greenhouse by 4.94 times on TSP (total suspended particle), 2.71 times on PM-10 (particle size of 10 ㎛ or larger), and 1.53 times on PM-2.5, respectively. During pruning operation in cut-rose greenhouse, TSP concentration was 7.4 times higher and PM-10 concentration was 3.2 times higher than during no-work period. As a result of analysis of PM contribution ratio by particle sizes, it was shown that PM-10 constitute the largest percentage. There was a significant difference in the PM concentration between work and no-work periods, and the concentration of PM during work was significant higher (p < 0.001). It was found that workers were generally exposed to a high level of dust concentration from 2.5 ㎛ to 35.15 ㎛ during tillage operation.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.3
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• pp.223-232
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• 2014

Monthly variations of radiative forcing (RF) and mean temperature changes by greenhouse gases emitted from commercial aircraft were estimated based on the simplified expression at four international airports (Incheon, Gimpo, Jeju, and Gimhae Airports) during the years of 2009~2010. The highest RF and mean temperature change in the study area occurred at Incheon Airport, whereas the lowest RF and mean temperature change at Gimhae Airport. During 2009~2010, the mean RF and mean temperature change estimated from aircraft $CO_2$ emissions at Incheon Airport were approximately 30.0 $mW/m^2$ and $0.022^{\circ}K$, respectively. The mean RF and mean temperature changes caused by other greenhouse gas $N_2O$ was significantly small (<<0.1 $mW/m^2$ and << $1{\times}10^{-3}^{\circ}K$). Meanwhile, $CH_4$ emissions caused negative mean RF ($-4.45{\times}10^{-3}mW/m^2$ at Incheon Airport) and the decrease of mean temperature ($-3.83{\times}10^{-6}^{\circ}K$) due to consumption of atmospheric $CH_4$ in the aircraft engine.

• Journal of Bio-Environment Control
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• v.8 no.4
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• pp.232-241
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• 1999

The automatic irrigation system using the stem diameter monitoring and the transpiration model for the determination, respectively, of irrigation timing and amount was designed and evaluated for its applicability in pot and field culture of greenhouse tomato. In the pot culture condition, the yield and quality of greenhouse tomato were improved when irrigation was practiced based on the stem diameter monitoring and the transpiration model as compared to the irrigation practice based on soil moisture monitoring. However, the effects were not significant in the field culture condition.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.290-297
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• 2010

The effect of supplemental light such as metal, Na and fluorescent lamp on the growth and productivity of tomato for 5 hours a day The growth rate of tomatoes under artificial light were increased 6~10% rather than the growth rate of tomatoes under no light treatment. Also the quantity and productivity of tomatoes under artificial light were increased rather than the quantity and productivity of tomatoes under no light treatment. Increasing profitability per 10a under artificial light were 9.4~28.2 million won.