• Horticultural Science & Technology
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• v.32 no.4
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• pp.448-453
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• 2014

Influences of shading and irrigation in summer hot pepper cultivation on the plant growth and mesophyll tissue were investigated. Hot pepper plants were exposed to three shade levels (0, $30{\pm}5$ and $80{\pm}5%$) and irrigated or non-irrigated in greenhouse condition. Plant height and leaf area were highest in 30% shading and stem diameter and fresh and dry weights were highest in no shading. Plant growth was better in rain shelters with irrigation than in those without irrigation. The numbers of hot pepper fruits in the beginning of harvest were 49 in rain shelters without irrigation and shading, 22 in those with irrigation and without shading, 5 in those without irrigation with 30% shading, and 1 in those with irrigation and 30% shading. However, 80% shading showed lowest flower number and flower abscission, resulting in no fruit set, regardless of irritation. This is because carbohydrate translocation from leaves to reproductive organs may be not enough for developing fruits due to the lack of sunlight. The yield of hot pepper tended to be higher in rain shelter with irrigation than in those without irrigation. In optical microscopy observation, the thickness and development of mesophyll tissues decreased as increasing the degree of shading but no effect of irrigation on mesophyll tissues was observed. When stomata were observed with scanning electron microscope (SEM), the shape of stomata was normal but tissues surrounding stomata were slightly wrinkled in plants grown under 30% shading. The large number of abnormal stomata and wrinkled leaves was observed among plants grown in rain shelters with 80% shading. In plants grown in rain shelters without irrigation, tissues surrounding stomata were wrinkled and 10-20% decrease in the number of stomata was observed. Therefore, in hot pepper cultivation in summer with high temperature, shading was not effective for fruit yield and mesophyll tissue development; if shading is unavoidable, high degree of shading is not advisable. Further studies are needed for appropriate cultivar selection and environment-control techniques in hot pepper cultivation in summer with high temperature.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.61-72
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• 2014

This paper analyzed transition pathways toward a low carbon society in Korea to meet global $2^{\circ}C$ climate target. Lower economic growth, industrial structure change, enhance of energy demand management, decarbonization of power sector, and replacement of low carbon fuel could reduce greenhouse gas (GHG) emission from fuel combustion in 2050 by 67% against in 2011, or by 74% against in BAU (Business-As-Usual). Lower economic growth contributes to 13% of cumulative emission reduction relative to BAU, industrial structure change 9%, enhance of energy demand management 72%, decarbonization of power sector 5% and replacement of low carbon fuel 1% respectively. Final energy consumption in 2050 needs to be reduced to 50% relative to 2011, or to 41% relative to BAU. Nuclear, coal and renewable energy represent 31%, 40%, 2% respectively among electricity generation in 2011, but 38%, 2%, 32% in 2050. CCS represents 23% of total generation in 2050. Emission intensity of electricity in 2050 was decreased to 19% relative to 2011, or to 24% relative to BAU. Primary energy in 2050 was decreased to 64% compared to 2011, or to 44% compared to BAU. Final energy consumption, primary energy supply and GHG emission from fuel combustion from 1990 to 2011 increased by 176%, 197%, 146%. Radical change from historical trend is required to transit toward a low carbon society by 2050. Appropriate economic growth, structural change to non-energy intensive industries, energy technology research, development and deployment (RD&D) in terms of enhancement of energy efficiency and low carbon energy supply technologies, and fuel change to electricity and renewable energy are key instruments.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.781-796
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• 2015

This study was carried out to investigate the effect of no-tillage and split irrigation on the growth of pepper plant under green house condition in Jeonnam province. Moisture content of soil at whole quantity irrigation in tillage was increased rapidly regardless of soil depth for initial irrigation and then was decreased continuously until next irrigation. Deviation of moisture content in soil was decreased with increasing depth of soil. Moisture contents of top soil and subsoil (20 cm) at whole quantity irrigation in no-tillage were increased with sunrise, and then decreased with sunset. Moisture contents of top soil in tillage, and top soil and subsoil (20 cm) in no-tillage at half quantity irrigation indicated a cyclic diurnal variation by evapotranspiration. Salinity of soil was increased after initial irrigation and then was decreased continuously until next irrigation. With increasing depth of soil, increases of salinity in soil was delayed. Salinity of top soil in no-tillage was increased between AM 11:00 and AM 12:00, and then showed the highest level between PM 2:00 and PM 6:00 on a cyclic diurnal variation by evapotranspiration. Salinity of subsoil (30 cm) in no-tillage was not measured a cyclic diurnal variation. Moisture content and salinity of soil was positive correlation regardless of tillage and no-tillage cultivation. Growth of pepper in no-tillage cultivation was higher than that in tillage cultivation. Main branch Length and stem diameter of half quantity irrigation plot was higher than that of whole quantity irrigation plot regardless of tillage and no-tillage cultivation. After harvesting, the number of pepper fruits of half quantity irrigation plot was increased remarkably by 49% and 47%, in tillage and no-tillage cultivation, respectively. Pepper yield of no-tillage cultivation plot was higher by 8% than that of tillage cultivation plot. Pepper yield of half quantity irrigation plot was increased remarkably by 36% and 39%, in tillage and no-tillage cultivation, respectively.

• Journal of Bio-Environment Control
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• v.19 no.3
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• pp.159-164
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• 2010

This study was carried out to compare the storability of Salsola komarovi Iljin and Suaeda maritima L. Dum which stored at different storage temperatures in MA storage. These plants that had grown in greenhouse packed with $50\;{\mu}m$ ceramic film and then stored in $2^{\circ}C$, $10^{\circ}C$, and $25^{\circ}C$ temperature. The fresh weight loss both plants was less than 1% in all temperature treatments. The highest fresh weight loss showed at $25^{\circ}C$ among storage temperature treatments in Salsola komarovi Iljin between plants. The highest carbon dioxide contents in package showed at $25^{\circ}C$ among storage temperature treatments in Salsola komarovi Iljin between plants, and at $2^{\circ}C$ and $10^{\circ}C$ temperature treatments remained less than 1%. Oxygen contents in package both plants showed the highest level at $2^{\circ}C$ temperature treatment, but Salsola komarovi Iljin showed less oxygen contents than Suaeda maritima L. Dum. Although there was no significant difference ethylene contents in package between $2^{\circ}C$ and $10^{\circ}C$ temperature treatments, the higher showed in $10^{\circ}C$ than $2^{\circ}C$ temperature treatments. The ethylene contents in package both plants were roughly $20\;{\mu}L{\cdot}L^{-1}$ and the higher was in Suaeda maritima L. Dum than Salsola komarovi Iljin at $2^{\circ}C$. As increasing the storage temperature, the contents of carbon dioxide and ethylene in package also increased in both plants. The carbon dioxide and ethylene contents of Salsola komarovi Iljin showed a significant difference between $2^{\circ}C$ and $10^{\circ}C$ temperature treatments, but Suaeda maritima L. Dum did not show. The shelf life of Salsola komarovi Iljin based on visual quality was 14 days at $2^{\circ}C$ temperature treatment and 7.5 days at $10^{\circ}C$ temperature treatment. However, the shelf life of Suaeda maritima L. Dum did not show a significant difference between $2^{\circ}C$ temperature treatment that was 11 days, and $10^{\circ}C$ temperature treatment that was 9.5 days. Considering visual quality and gas contents in package, Suaeda maritima L. Dum might appear chilling injury at $2^{\circ}C$ temperature treatment.

• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.188-193
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• 2017

The purpose of this study was to investigate the changes of environmental conditions and the quality and yield of melon fruit by heat fan operation in greenhouses at winter season. The average daily temperature inside the tunnels during January 1 to 31, 2017 was $0.9^{\circ}C$ higher than that of the control $17.8^{\circ}C$. The air flow rate of heater fan treatment was 4.8 times higher than the control (untreated $0.05m{\cdot}s^{-1}$) at 20cm above the ground where the korean melon grew. The temperature of the heater pan was $5.6^{\circ}C$ higher than that of the untreated at $35.3^{\circ}C$ and the relative humidity was 8.1% lower than that of the untreated at 39.1%. The flowering rate of the heater fan treatment was 96%, 5% higher than the control. The number of first harvest days of heater fan treatment was shortened by 4 days than that of untreated treatment. Fruit quality and marketable fruit yield increased by 3.4% and 38% compared to untreated respectively, the heater fan treatment increased the temperature inside the greenhouse and air flow rete, which were beneficial for growing the korean melon in greenhouses at winter season.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.15-24
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• 2019

The study was compared for soil chemical and microbial properties as well as growth of the cherry tomato (Lycopersicon esculentum var. cerasiforme) plants environmentally friendly gown for 3 years and 5 years, which had been fertigated with homemade liquid fertilizer (LF) with indigenous microorganism as an additional fertilizer. Treatment included LF with indigenous microorganism for 3 years (3-year IM-LF) and for 5 years (5-year IM-LF), with an effective microorganism for 10 years (EM-LF), which had been applied with 1,000 times of dilution in the farmhouse. IM-LF and EM-LF materials had increased pH pattern for 16 weeks, in particular for increase of 1.2 for EM-LF. IM-LF material contained slightly higher EC but similar level of 0.2 dS/m to EM-LF. For a pot experiment in the greenhouse, IM-LF treatment increased root dry weight of the cherry tomato plants. In the farmhouse experiment, IM-LF treatment increased to 7.5 of soil pH and 8.4 dS/m of EC, indicating high salt accumulation. EM-LF treatment increased to 62 g/kg of soil OM, which would have affected concentrations of macro essential nutrients, including T-N in the soil. However, the optimum soil chemical levels for growth of cherry tomato plants were observed on the IM-LF plots. EM-LF treatment increased number of bacteria and actinobacteria in the soil. EM-LF treatment increased concentrations of macro essential nutrients in the plants, except for P, with similar nutrient concentrations observed between 3-year IM-LF and 5-year IM-LF-treated plants. Leaf SPAD and PS II levels decreased in the plants treated with 3-year IM-LF. EM-LF treatment increased leaf width and length, number of leaves, canopy area, plant height, and stem diameter in the mid-term stage of growth, which were not significantly different between the treatments. EM-LF treated-plants had two times higher leaf dry weight than those of values observed on the IM-LF plants, which was the opposite result observed on the number of fruit.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.72-77
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• 2017

This study was conducted to examine the effect by application method and concentration of plant growth regulator (PGR) on the growth and runner production of strawberry (Fragaria ${\times}$ ananassa Duch. cv. Maehyang) in a velno-type greenhouse. The seedlings of strawberry were transplanted in pot ($64{\times}27{\times}18cm$) filled with commercial mixed medium (Tosilee) on February 22nd, 2016. The 6-benzylaminopurine (6-BAP) was applied with foliar spray or drench, respectively as 900, 1,200 or $1,500mg{\cdot}L^{-1}$ (50 mL per plant) at 3 weeks after transplanting. Nutrient solution was sufficiently supplied by the drip irrigation as EC $0.65dS{\cdot}m^{-1}$ for rooting during 7 days. After rooting, the 450 mL nutrient solution supplied per pot twice a day (10 min). Plant height and crown diameter of 'Maehyang' mother plant appeared no significantly difference. The other growth characteristics, such as root length, number of primary roots, leaf length, leaf width, leaf area and fresh and dry weights of the shoot or root, were significantly the greatest in the control. And, the SPAD value of strawberry was the highest as 44.2 in the drench with $900mg{\cdot}L^{-1}$. The foiler spray was more effective in runner production than drench, and the number of runners appeared high values at the 900 and $1,500mg{\cdot}L^{-1}$. Whereas, the number of strawberry plantlets was effective in the drench. The results indicate that both growth and the number of runners of strawberry plant were the best achieved by foliar spray application at the $900mg{\cdot}L^{-1}$.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.999-1005
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• 2008

The main reaction for soil washing with using sodium hydroxide(NaOH) and hydrogen peroxide(H$_2$O$_2$) was desorption and flotation of petrochemical contaminant by means of oxygen bubble. We found the rate of decomposition by rate constant according to various temperature. For the purpose of optimizing the operation factor, we examined the effect of concentration of NaOH and H$_2$O$_2$, washing time, and soil:water ratio. The rate of decomposition for H$_2$O$_2$ in liquid phase is the first order reaction by its concentration. The rate constant of k$_1$ was 0.9439 $\times$ exp(-1376.82/RT) when concentration of NaOH was lower than 0.1 M, and the rate constant of k$_2$ was 17.3588 $\times$ exp(-2320.06/RT) when it was higher than NaOH of 0.1 M. It found that NaOH was facilitated at the beyond of specific concentration. We confirmed the optimum concentration of NaOH/H$_2$O$_2$ by means of rate constants during soil washing. Also, the optimum conditions during soil washing were washing time of 15 min, soil : water ratio of 1 : 3, and NaOH/H$_2$O$_2$ concentration of 0.25 M/0.1 M.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.2
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• pp.94-101
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• 2015

To mitigate the greenhouse gas emission, many carbon capture and storage projects are underway all over the world. In Korea, many studies focus on the storage of $CO_2$ in the offshore sediment. Assurance of safety is one of the most important issues in the geological storage of $CO_2$. Especially, the assessment of possibility of leakage and amount of leaked $CO_2$ is very crucial to analyze the safety of marine geological storage of $CO_2$. In this study, the leakage of injected $CO_2$ through fault was numerically studied. TOUGH2-MP ECO2N was used to simulate the subsurface behavior of injected $CO_2$. The storage site was 150 m thick saline aquifer located 825 m under the continental shelf. It was assumed that $CO_2$ leak was happened through the fault located 1,000 m away from the injection well. The injected $CO_2$ could migrate through the aquifer by both pressure difference driven by injection and buoyancy force. The enough pressure differences made it possible the $CO_2$ to migrate to the bottom of the fault. The $CO_2$ could be leaked to seabed through the fault due to the buoyancy force. Prior to leakage of the injected $CO_2$, the formation water leaked to seabed. When $CO_2$ reached the seabed, leakage of formation water stopped but the same amount of sea water starts to flow into the underground as the amount of leaked $CO_2$. To analyze the effect of injection rate on the leakage behavior, the injection rate of $CO_2$ was varied as 0.5, 0.75, and $1MtCO_2/year$. The starting times of leakage at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 11.3, 15.6 and 23.2 years after the injection, respectively. The leakage of $CO_2$ to the seabed continued for a period time after the end of $CO_2$ injection. The ratios of total leaked $CO_2$ to total injected $CO_2$ at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 19.5%, 11.5% and 2.8%, respectively.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.236-241
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• 2012

The characteristics of chlorpyrifos was studied to clarify the effect of the cultivation season, spray intervals, spray volume and concentration on residues in chilli and sweet peppers cultivated under greenhouse condition. Residue levels of chlorpyrifos detected in chilli pepper fruit cultivated were 1.5 to 2.7 times higher in winter(February-March) than those in summer(June-July). During winter season residue levels of chlorpyrifos in chilli peppers were 6.9~3.2 times higher than those in sweet peppers for 10 days after 3 times application with 7 days interval. Residue levels in chilli pepper were from 2.070 mg/kg at 1 day to 0.929 mg/kg at 10 day, while those in sweet pepper were from 0.302 mg/kg to 0.291 mg/kg. Residue levels in sweet pepper to which are 3 times applied with 7 days interval were from 0.302 mg/kg at 1 day to 0.291 mg/kg at 7 day, and the residue levels in sweet pepper which are 3 times applied with 3 days interval were from 0.498 mg/kg at 1 day to 0.470 mg/kg at 7 day. Residue levels of chlorpyrifos in the sweet peppers applied by double concentration were 2.5 times higher than those sprayed by normal standard amounts diluted in double volume.