• Journal of Hydrogen and New Energy
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• v.35 no.2
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• pp.175-184
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• 2024

This study focuses on investigating the importance of managing greenhouse gas emissions from global energy consumption, specifically examining domestic targets for clean hydrogen production. Using life cycle assessment, we evaluated reductions in global warming potential and assessed the carbon neutrality contribution of the domestic hydrogen sector. Transitioning from brown or grey hydrogen to blue or green hydrogen can significantly reduce emissions, potentially lowering CO₂ equivalent levels by 2030 and 2050. These research findings underscore the effectiveness of clean hydrogen as an energy management strategy and offer valuable insights for technology development.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.400-406
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• 2013

This study was conducted to investigate the growth and flowering of African marigold (Tagetes erecta L.) and salvia (Salvia splendens F. Sello ex Ruem & Schult.) seedlings before and after storage under fluorescent lamps and green LED radiation conditions with different light intensities during storage. The both seedlings were kept under a storage room controlled at $8^{\circ}C$ air temperature and $40{\pm}10%$ relative humidity conditions. Light intensities were maintained at 15 and $30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ during storage. In lighting treatments, dry weight of African marigold at 28 days after storage was not significantly different, and decreased approximately 29% compared to pre-storage under dark treatment. There was no significant difference in the leaf area of salvia seedlings stored under dark condition compared to before storage, but the leaf area under green light radiation with higher light intensity (treatment GH) was two times greater than before storage. The survival rate after transplanting of African marigold stored under dark condition was 10%, and days to flowering increased compared to those stored under fluorescent and green light with higher light intensity (treatment FLH, GH). Comparing to before storage, growth and flowering of the both seedlings after storage were significantly promoted by the light exposure during storage. The present experimental results show that the light intensity should be decided to maintain minimum growth during lighting storage and storage quality of the seedlings such as flowering promotion and extended blooming period after lighting treatment during storage period from the above results.

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.125-135
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• 2013

Analysis and evaluation of uncertainty is adopting the advanced methodology among the methods for greenhouse gas emission assessment that was defined in GPS2000 (Good practice guideline 2000) and GPG-LULUCF (GPG Land Use, Land-Use Change and Forestry). In 2006 IPCC guideline, two approaches are suggested to explain the uncertainty for each section with a national net emission and a prediction value on uncertainty as follows; 1) Spread sheet calculation based on the error propagation algorithm that was simplified with some assumptions, and 2) Monte carlo simulation that can be utilized in general purposes. There are few researches on the agricultural field including greenhouse gas emission that is generated from livestock and cultivation lands due to lack of information for statistic data, emission coefficient, and complicated emission formula. The main objective of this study is to suggest an evaluation method for the uncertainty of greenhouse gas emission in agricultural field by means of intercomparison of the prediction value on uncertainties which were estimated by spread sheet calculation and monte carlo simulation. A statistic analysis for probability density function for uncertainty of emission rate was carried out by targeting livestock intestinal fermentation, excrements treatment, and direct/indirect emission from agricultural lands and rice cultivation. It was suggested to minimize uncertainty by means of extraction of emission coefficient according to each targeting section.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.43-47
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• 1997

This study was carried out in the laboratory to clarify effects of different temperature of Protopulvinaria mangiferae(Green) on development, survivorship and reproduction. Developmental period of the mango shieldscale from crawlers to preoviposition adult decreased as temperature increased. The threshold temperature andthermal constants for the development of one generation were 11.7"C and 1000.0 day-degrees, respectively. At25$^{\circ}$C and 30$^{\circ}$C, survival rate from egg to preoviposition adult were 82% and 6096, respectively. Hatchability ofeggs was more than 99% at both condition. The reproductive period overaged 50 days(2SnC) and 33 days(30$^{\circ}$C). After mature adult began to reporduce, and more than 50% of the crawlers emerged during the firsthalf of their life time. The net reproduction rate per generation(R), mean length of a generation0 and intrinsicrate of natural increase(r, ) were higher at 25$^{\circ}$C than at 30"C, and the values measured at 25$^{\circ}$C were 132.6, 76.2 and 0.064/female/day, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.10
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• pp.1302-1309
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• 2021

Recently, the Korean Government announced the Korean New Deal as a national development strategy to overcome the economic recession from the pandemic crisis and lead the global action against structural changes. In the Korean New Deal, the Green New Deal related with the energy aims to achieve net-zero emissions and accelerates the transition towards a low-carbon and green economy. To this end, the government plans to promote an increased use of renewable energy in the society at large. This paper introduces a binary power generation using unused low-grade thermal energy to accelerate the transition towards a low-carbon and green economy and examines a control system based on Neural Network which is capable maintenance at low-cost by an unmanned automated operation in actual power generation environment. It is expected that the realization of binary power generation accelerates introduction of renewable energy along with solar and wind power.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.557-560
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• 2021

In the face of the COVID-19 pandemic, the Korean Government announced the Korean New Deal as a national development strategy to overcome the economic recession from the pandemic crisis and lead the global action aginst sturctural changes. The Green New Deal related with the energy aims to achieve net-zero emissions and accelerates the transition towards a low-carbon and green economy. To this end, the government plans to promete an increased use of renewable energy in the the society at large. This paper introduces a compact-binary power plant using unused thermal energy and a control system based on Neural Network in order to accelerate the transition towards a low-carbon and green economy. It is expected that he compact-binary power plant accelerate introduction of renewable energy along with solar and wind power.

• Journal of Environmental Science International
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• v.33 no.6
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• pp.417-425
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• 2024

This study investigated the effects of various planting models on the joint cultivation of eggplant (Solanum melongena) and marigold (Tagetes erecta)to enhance sustainable rooftop urban farming. Rooftop agriculture is increasingly valued to boost the food supply and benefit the environment. Integrating such practices into urban planning is viewed as a way to sustainably manage resources and improve the food-energy-water cycle in cities. The experiment was conducted on a rooftop in Chungju, South Korea from May to August. Four different planting setups were used: central eggplant with peripheral marigold (SET), eggplant with a protective net (SIC), central marigold with peripheral eggplant (TES), and control with only eggplant (CON S). These models tested the effects of companion planting versus monoculture using a lightweight soil mix ideal for rooftops made from cocopeat and perlite and enriched with organic fertilizer. Measurements focused on soil conditions and plant health and assessed soil temperature, moisture, conductivity, plant height, width, and leaf size. The results indicated that the SET modelyielded the best growth. This setup benefited from marigold pest control properties and its ability to improve soil conditions by enhancing moisture and nutrient levels and aiding eggplant growth. These findings underscore the potential of mixed planting on rooftops and suggest that such approaches can be effectively incorporated into urban agriculture to boost yield and environmental sustainability. This study supports the idea that diverse planting methods can significantly affect plant growth and promote urban greening and food security.

• Korean Journal of Environment and Ecology
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• v.33 no.3
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• pp.354-365
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• 2019

This study measured and analyzed the weather characteristics and the air-ion characteristics of walking space by land use type in Chungju, Chungcheongbuk Province during the heat wave. We used the land registration map to classify the type of land use in walking areas in the studied into the production and green area, the residential area, and the commercial area. We then selected 44 measurement points in about 4.1 km. They included 12 walking space points in the green area, 14 in the residential area, and 18 in the commercial area. Moreover, we calculated the ion index by analyzing the impact of weather factors such as temperature, relative humidity, solar radiation, and net radiation in the walking space on the anion generation and cation generation by land use type during the heat wave. Comparison of air ion characteristics in walking space by type of land use during the heat wave showed that the average cation generation was in the order of commercial area ($700.73cations/cm^3$) > residential area ($600.76cations/cm^3$) > green area ($589.73cations/cm^3$). The average anion generation was in the order of green area ($663.95anions/cm^3$) > residential area ($628.48anions/cm^3$) > commercial area ($527.48anions/cm^3$). The average ion index was in the order of green area (1.13) > residential area (1.04) > commercial area (0.75). This study checked the weather characteristics, cation generation, and anion generation in walking space according to the land use type during the heat wave and checked the difference of ion indexes in the walking space according to the land use type. However, there were limitations in the lack of accurate comparison according to the land use due to the moving measurement and the insufficient quantitative comparison according to the change of road width. Therefore, we recommend further studies that consider the road characteristics.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.190-197
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• 2012

The purpose of this study was to evaluate thermal environment and heat budget of light thin layer green roof through an experiment in order to quantify its heat budget. Two concrete model boxes($1.2m(W){\times}1.2m(D){\times}1.0m(H)$) were constructed: One experiment box with Zoysia japonica planted on substrate depth of 10cm and one control box without any plant. Between June 6th and 7th, 2012, outside climatic conditions(air temperature, relative humidity, wind direction, wind speed), evapotranspiration, surface and ceiling temperature, heat flux, and heat budget of the boxes were measured. Daily maximum temperature of those two days was $29.4^{\circ}C$ and $30^{\circ}C$, and daily evapotranspiration was $2,686.1g/m^2$ and $3,312.8g/m^2$, respectively. It was found that evapotranspiration increased as the quantity of solar radiation increased. A surface and ceiling temperature of those two boxes was compared when outside air temperature was the greatest. and control box showed a greater temperature in both cases. Thus it was found that green roof was effective in reducing temperature. As results of heat budget analysis, heat budget of a green roof showed a greater proportion of net radiation and latent heat while heat budget of the control box showed a greater proportion of sensible heat and conduction heat. The significance of this study was to analyze heat budget of green roof temperature reduction. As substrate depth and types, species and seasonal changes may have influences on temperature reduction of green roof, further study is necessary.

• Korean Chemical Engineering Research
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• v.49 no.2
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• pp.244-249
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• 2011

In this study, performance and economic analysis of 500 MWe coal-fired power plant with $CO_{2}$ capture process was performed. For this purpose, chemical absorption method which is commercially available and most suitable for thermal power plant was studied and a criteria for technical and economic assessment of power plants suggested by IEA Greenhouse Gas R&D Programme was used. And we performed the sensitivity analysis focused on regeneration energy which exceed half of the total capture energy. Based on MEA(Monoethanoleamine) as a main chemical solvent and 3.31 GJ/ton$CO_{2}$ regeneration energy in the stripper, net power efficiency was reduced from 41.0% (no capture) to 31.6%(with capture) and the cost of $CO_{2}$ avoided was estimated 43.3 $/ton$CO_{2}$. And in case of 2.0 GJ/ton$CO_{2}$ regeneration energy, the cost of $CO_{2}$ avoided was calculated as 36.7 $/ton$CO_{2}$.