• Journal of Climate Change Research
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• v.2 no.2
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• pp.93-106
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• 2011

Republic of Korea officially announced its mid term reduction target which reduce about 30% of BAU GHG emission by 2020 in the 15th meeting of UNFCCC(COP 15) held in Copenhagen, Denmark 2009. To achieve this goal, it is necessary to understand the serious of climate change and take part in GHG reduction not only industry but also the nation. However, such positive participation in green life which may cause inconvenient of the life of the people. It should be accomplished with providing reliable information. This study suggests the scientific potentialities of GHG emission by guideline on low carbon life and green life to form and change a lifestyle suitable for coping with climate change. And also, this study quantitate the GHG reduction which may reduce demand for air conditioning by cool biz and warm biz. In Korea, this campaign has become known as 'CoolMaebsi' by Ministry of Environmental of Korea. 'CoolMaebsi' is a compound word of 'Cool' which means feel refreshed, and 'Maebsi' is a Korean word which means attire. Though this campaign is effective and significant to reduce the GHG emission yet there were no study on quantitative analysis. Therefore this study calculated reduced energy consumption and potential GHG emission by measuring variation of skin temperature. As the result, wearing warm biz and cool biz have an effect of reducing not only the energy consumption but also GHG emission. To achieve the low carbon society, it is necessary to improve the energy saving system and introduce the policy which guide to change a life style.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.391-399
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• 2018

In this paper, experimental study performed on steel-pipe connections for structural members of a greenhouse is presented. By those experiments performed, bending moment, deformation and stress distribution of specimens were investigated under four point bending test. The bending performance according to connection method using pin and the stretching is also investigated. The results of bending performance of the no connection specimen were compared to those of other connection specimens. The pin and stretching connection specimens showed lower banding performance than the no connection specimen. The stretching connection method was relatively higher bending performance than the pin connection specimens. According to the results, we proposed the connection method with good bending performance that can be applied to steel-pipe connection in greenhouse.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.606-612
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• 2022

Relatively high indoor CO₂ concentration (>1,000 ppm) has a negative impact on human health. In this work, indoor CO₂ adsorbent was developed by impregnating KOH or K₂CO₃ on commercial activated carbon, named as KOH/AC and K₂CO₃/AC. Commercial activated carbon (AC) showed relatively high BET surface area (929 m²/g) whereas KOH/AC and K₂CO₃/AC presented lower BET surface area of 13.6 m²/g and 289 m²/g. Two experimental methods of TGA (2,000 ppmCO₂, weight basis) and chamber test (initial concentration: 2,000 ppmCO₂, CO₂ IR analyzer) were used to investigate the adsorption capacity. KOH/AC and K₂CO₃/AC exhibited similar adsorption capacities (145~150 mg_CO2/g), higher than K₂CO₃/Al+Si supports adsorbent (84.1 mg_CO2/g_sample). Similarly, chamber test also showed similar trend. Both KOH/AC and K₂CO₃/AC represented higher adsorption capacities (KOH/AC: 93.5 mg_CO2/g K₂CO₃/AC: 94.5 mg_CO2/g_sample) K₂CO₃/Al+Si supports. This is due to the KOH or K₂CO₃ impregnation increased alkaline active sites (chemical adsorption), which is beneficial for CO₂ adsorption. In addition, the regeneration test results showed both K-based adsorbents pose a good regeneration and reusability. Finally, the current study suggested that both KOH/AC and K₂CO₃/AC have a great potential to be used as CO₂ adsorbent for indoor CO₂ adsorption.

• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.73-79
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• 2020

The objective of this study is to analyze the heat transfer loss of covering materials in a single-span plastic greenhouse under the steady-state wind environment. To achieve this objective, the following were conducted: (1) design of a small-scaled wind tunnel (SCWT) to analyze heat losses of the greenhouse and its performance; (2) determination of the overall heat transfer coefficient (OHTC) for the covering materials using a small-scaled greenhouse model. The SCWT consists of the blowing, dispersion, steady flow, reduction and testing areas. Each part of the SCWT was customized and designed to maintain air flow at steady state and to minimize the variances in the SCWT test. In this study, the OHTCs of the covering materials were calculated by separating each with the roof, side wall, front and back of the small-scaled greenhouse model. The results of this study show that the OHTC of the roof increases as wind speed increases but the zones in which the increase rate of the OHTC decreased, were distinguished by wind tunnel wing speed of 2 ms^-1. For the side wall, the increase rate of the OHTC was particularly higher in the 0-1 ms^-1 zone.

• Journal of Bio-Environment Control
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• v.11 no.2
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• pp.56-60
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• 2002

Since the transmittance of solar radiation directly affected by the structural frames of greenhouse can be changed according to the ratio of diffuse to direct radiations, it is necessary to investigate the transmittance of greenhouse at the different weather conditions. We can easily get the data of total solar radiation from the Meteorological Administration, but we have to personally measure the photosynthetic photon flux (PPF). If the relationship between total solar radiation and PPF is established, the PPF can be simply acquired from the relationship. Sol it is required to develop the equation to calculate PPF depending on weather condition. This study was conducted to determine the transmittance of PPF at canopy level in glasshouse and the correlation between total solar radiation and PPF at clear and cloudy days. The variation phase of greenhouse transmittance at clear day was very different from that at cloudy day. It was concluded that the proper transmittance, depending on the weather condition, should be adopted to calculate the accurate total solar radiation and PPF in greenhouse. The transmittance of solar radiation was the same as that of PPF in greenhouse. It was confirmed that the ratio of PPF to total radiation increased as the amount of cloud increased. The correlation between the hourly total solar radiation and PPF was derived.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.4
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• pp.129-134
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• 2018

Recently, the artificial neural network (ANN) model is a promising technique in the prediction, numerical control, robot control and pattern recognition. We predicted the outside temperature of greenhouse using ANN and utilized the model in greenhouse control. The performance of ANN model was evaluated and compared with multiple regression model(MRM) and support vector machine (SVM) model. The 10-fold cross validation was used as the evaluation method. In order to improve the prediction performance, the data reduction was performed by correlation analysis and new factor were extracted from measured data to improve the reliability of training data. The backpropagation algorithm was used for constructing ANN, multiple regression model was constructed by M5 method. And SVM model was constructed by epsilon-SVM method. As the result showed that the RMSE (Root Mean Squared Error) value of ANN, MRM and SVM were 0.9256, 1.8503 and 7.5521 respectively. In addition, by applying the prediction model to greenhouse heating load calculation, it can increase the income by reducing the energy cost in the greenhouse. The heating load of the experimented greenhouse was 3326.4kcal/h and the fuel consumption was estimated to be 453.8L as the total heating time is $10000^{\circ}C/h$. Therefore, data mining technology of ANN can be applied to various agricultural fields such as precise greenhouse control, cultivation techniques, and harvest prediction, thereby contributing to the development of smart agriculture.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.532-538
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• 1996

GA4/7 spray, injection and several cultural treatments were applied to the greenhouse-grown potted hybrid larch(Larix decidua${\times}$leptolepis) grafts and field-grown European larch seedlings to induce early flowering. A treatment consisting of repeat-ed GA4/7 sprays, alone, was the most effective flower induction treatment for greenhouse-grown, potted larch grafts. Root pruning as a adjunct treatment did not show synergistic effects. Injection for potted grafts with GA4/7 was not useful approach in this study and it resulted in increased mortality. In the field experiment with 10-Year-old larch seedlings, repeated GA4/7 sprays in combination with root pruning or with plastic mulching appears to be useful and practical means for inducing larch flowers:

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.220-227
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• 2013

This study examined the electric power quantity derived from solar radiation after installing a photovoltaic power generation system on the rooftop of building adjacent to a greenhouse with a view to reducing the operating expenses of the greenhouse by securing electric energy required to run it. Results of the study can be summed up as follows: The maximum, mean, and minimum solar radiation on the horizontal plane was $26.1MJ{\cdot}m^{-2}$, $14,0MJ{\cdot}m^{-2}$, and $0.6MJ{\cdot}m^{-2}$, respectively and individual the daily electric energy generated was about 6.1 kWh, 3.7 kWh, and 0.01 kWh. The cumulative total amounts of solar radiation and electric energy was about $4,378.2MJ{\cdot}m^{-2}$ and 1,163.2 kWh, respectively. Maximum, mean and minimum cumulative electric energy consumed through each load respectively was 4.5 kWh, 2.4 kWh, and 0.0 kWh and the cumulative electric energy were 739.2 kWh, which accounted for about 63.5% of generated power. In case of the mean amount of power consumption of the system used for this study, the small capacity of heater and the short operating hours meant there was enough power; while big capacity of heater led to a shortage, and if the array surface temperature increased relatively, the energy became proportionate to solar radiation and generated power does not increase. The correlation coefficient between the two factors was 0.851, which indicates a high correlation coefficient.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.202-209
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• 2015

This study compared and analyzed the measurements of pullout load according to the depth of reclamation in the foundation, compaction ratio of soil, spiral diameter, and soil textures in an experiment with a model and reached the following conclusions: The comparison results of extreme pullout load between farm and reclaimed soil show that farmland soil recorded a score that was 1.2~3 times higher than that of reclaimed soil. The investigator measured pullout load in farmland and reclaimed soil and observed a tendency of rising extreme pullout load according to the increasing depth of reclamation and compaction ratio with a similar load-displacement curve between the two types of soil. Extreme pullout load made a greater increase by the rising size of diameter than the increasing depth of reclamation, also making a considerably bigger increase according to the rising compaction ratio than the other conditions. Therefore, the spirals bar is expected to be available in soft soil foundation, as well as farmland as increasing buried deep of foundations, compaction rate, diameter of the spiral, ect.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.475-480
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• 2011

This study was conducted to investigate the effects of different feeding level of TDN (Total Digestible Nutrients) on the generation of main greenhouse gases such as carbon dioxide and methane in Hanwoo cows. The diet TDN (kg) adjusted to achieve ADG of 0 g/day (Control), 200 g/day (T1), and 400 g/day (T2) of the maintenance level TMR (Total Mixed Ration) delivered twice a day at 08:30 and 17:30. Cow are housed in a respiration chamber and the environmental temperature was maintained at $20^{\circ}C$. The gases were measured for 24 hours using the multi-detector instrument Mamos-300. The analyzed methane emissions of T1 and T2 were 33.5% and 69.6% higher than control, respectively, and the carbon dioxide emissions were 21.1% and 40.6% higher than control. Also, the hourly pattern of carbon dioxide and methane production were showed very similar emission. Gas production showed peak after 1 hour of feeding and this gap was wider in the afternoon than in the morning hours. It is clearly conducted that $CO_2$ and $CH_4$ emissions were different by limited intake levels of feed.