• Journal of Practical Agriculture & Fisheries Research
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• v.21 no.1
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• pp.115-122
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• 2019

Foliar fertilization of carbonated water during lettuce hydroponic cultivation was increased photosynthetic rate and stomatal conductance as higher carbon dioxide concentration of carbonated water The higher the carbon dioxide concentration in the carbonated water was better growth of lettuce. However, the carbon dioxide concentration of 500 ppm and 700 ppm in the carbonated water was increased the tip-burn occurrence, and the yield was higher in the 300 ppm. the carbon dioxide concentration of 300 ppm in the carbonated water was lower in the fresh weight but increased yield resulted in the lower of the tip-burn occurrence The high temperature limits for growth were 32℃ in the control, 33℃ in the 300ppm and 34℃ in the 500 ppm according to analyze chlorophyll fluorescent Fo. The high temperature tolerance in lettuce increased approximately 4℃ by foliar fertilization treatments of carbonated water under this experiment conditions. Also the activity of SOD(superoxide dismutase), the antioxidant enzyme, was higher with high carbon dioxide concentration of the carbonated water.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.3
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• pp.138-149
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• 2008

Rapid accumulation of carbon dioxide in the atmosphere for the past century leads to acidify the surface ocean and contributes to the global warming as it forms acid in the ocean and it is a green house gas. In order to curb the green house gas emissions, in particular carbon dioxide, various multilateral agreements and programs have been established including UN Convention of Climate Change and its Kyoto Protocol for the last decades. Also a number of geo-engineering projects to manipulate the radiation balance of the earth have been proposed both from the science and industrial community worldwide. One of them is ocean fertilization to sequester carbon dioxide from the atmosphere through the photosynthesis of phytoplankton in the sea. Deliberate fertilization of the ocean with iron or nitrogen to large areas of the ocean has been proposed by commercial sector recently. Unfortunately the environmental consequences of the large scale ocean iron fertilization are not known and the current scientific information is still not sufcient to predict. In 2007, the joint meeting of parties of the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 and 1996 Protocol (London Convention/Protocol) has started considering the purposes and circumstances of proposed large-scale ocean iron fertilization operations and examined whether these activities are compatible with the aims of the Convention and Protocol and explore the need, and the potential mechanisms for regulation of such operations. The aim of this paper is to review the current development on the commercial ocean fertilization activities and management regimes in the potential ocean fertilization activities in the territorial sea, exclusive economic zone, and high seas, respectively, and further to have a view on the emerging international management regime to be London Convention/Protocol in conjunction with a support from the United Nations General Assembly through The United Nations Open-ended Informal Consultative Process on Oceans and the Law of the Sea.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.29-39
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• 2009

The influence of windbreak to minimize the ventilation velocity near the plant canopy of a greenhouse strawberry was thoroughly investigated using computational fluid dynamics (CFD) technology. Windbreaks were constructed surrounding the plant canopy to control ventilation and maintain the concentration of the supplied $CO_2$ from the soil surface close to the strawberry plants. The influence of no windbreak, 0.15 m and 0.30 m height windbreaks with varied air velocity of 0.5, 1.0 and 1.5 m/s were simulated in the study. The concentrations of supplied $CO_2$ within the plant canopy of were measured. To simplify the model, plants were not included in the final model. Considering 1.0m/s wind velocity which is the normal wind velocity of greenhouses, the concentrations of $CO_2$ were approximately 420, 580 and 653 ppm ($1{\times}10^{-9}kg/m^3$) for no windbreak, 0.15 and 0.30 m windbreak height, respectively. Considering that the maximum concentration of $CO_2$ for the strawberry plants was around 600-800 ppm, the 0.30 m windbreak height is highly recommended. This study revealed that the windbreak was very effective in preserving $CO_2$ gas within the plant canopy. More so, the study also proved that the CFD technique can be used to determine the concentration of $CO_2$ within the plant canopy for the plants consumption at any designed condition. For an in-depth application of this study, the plants as well as the different conditions for $CO_2$ utilization, etc. should be considered.

• Korean Journal of Environment and Ecology
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• v.13 no.2
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• pp.101-108
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• 1999

이산화탄소는 기후변화를 야기시키는 주요 온실가스이다. 본 연구는 춘천시, 강릉시, 서울시 강남구 및 중랑구를 대상으로 토지이용유형별 식생관리에 기인한 에너지소비 및 탄소방출을 잔디깎기, 전정, 관수, 시비, 살충제시용 등의 식생관리실태를 면담설문 및 일부 실측을 통해 파악하였다. 동일 토지이용유형 내 식생관리강도는 대체로 도시간 및 구간 통계적으로 유의한 차이가 없었다. 수목관리에 의한 연간 총탄소방출량은 토지이용유형에 따라 단위피도면적당 36.0~209.7g/m2로서 교통용지에서 가장 많았다. 잔디관리에 의한 연간 총탄소방출량은 단위잔디면적당 7.4~69.3g/m2로서 공원에서 가장 많았다. 이들 총탄소방출량 중 수목의 경우 전정이 토지이용유형에 따라 96.8~99.7%를, 잔디의 경우 잔디깎기가 91.9~100%를 각각 차지하였다. 도시식생의 연간 순탄소흡수를 최대화하기 위해서 가로수의 전정과 공원 내 잔디깎기에 의한 탄소방출을 최소화할 식재계획 및 관리가 요구된다.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2018.06a
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• pp.77-78
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• 2018

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.352-357
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• 2007

We investigated effects of concentration and duration were investigated in order to promote efficiency of $CO_2$ enrichment in winter. The treatments were conducted with two levels of $CO_2$ concentration, namely 400 ppm, 700 ppm, two levels of duration, 3 h (9:00-12:00), 6 h (9:00-15:00), and control (nonenrichment $CO_2$). Fresh weight of leaves increased under longer exposure to $CO_2$ and higher $CO_2$ concentration. Fresh weight of stem and root increased under longer exposure to $CO_2$, but decreased under higher $CO_2$ concentration. Total dry weight increased under longer exposure to $CO_2$ and higher $CO_2$ concentration. Combination treatment of longer exposure to $CO_2$ and higher $CO_2$ concentration showed the largest decrease of Root : Shoot dry weight ratio. The $700ppm{\times}6h$ treatment showed higher fruit number and yield than control. The results suggested that the growth under longer exposure to 400 ppm $CO_2$ was better than that under higher $CO_2$ concentration.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.140-145
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• 2017

This study was conducted to find out the effects of $CO_2$ fertilization (1,000ppm) on the quality and storability of 'Maehyang' strawberry fruits. Qualities such as firmness, soluble solid, and acidity of strawberry fruits showed higher numbers in those treated with $CO_2$ fertilization compared to those after harvest. Strawberry fruits were stored at $8^{\circ}C$; MA condition using $20,000cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ OTR (oxygen transmission rate) films and conventional condition using unsealed PE box stored for 20 and 10 days, respectively. Fresh weight loss rate was less than 1.0% in MA storage regardless of $CO_2$ fertilization treatment. Concentrations of oxygen, carbon dioxide, and ethylene in OTR films did not show any significant difference between $CO_2$ fertilization treatment and control (nontreatment) during storage. $CO_2$ fertilization treatments maintained higher firmness after storage regardless of storage methods, but soluble solid, acidity, and surface color did not differ among the treatments. Visual quality and off-flavor based on sensory evaluation was the highest in $CO_2$ fertilization treated strawberry and stored at a MA condition, and was the lowest in $CO_2$ fertilization treated strawberry and those stored in a conventional condition, respectively. The fungal incidence rate of strawberry fruits showed less in $CO_2$ fertilization treatment than control during both MA and conventional storage. These results suggest that $CO_2$ fertilization can improve firmness, increase visual quality after harvest and storage at $8^{\circ}C$, and the MA storage method enhances the shelf-life of 'Maehyang' strawberry fruits.

• Proceedings of the KIPE Conference
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• 2009.11a
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• pp.78-80
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• 2009

최근 화석에너지원의 고갈과 고유가 및 지구 온난화 방지를 위해 국가별로 이산화탄소 배출량을 규제하기 시작하면서 신재생 에너지의 사용에 대한 관심이 높아지고 있다. 그 중 연료전지가 한 부분을 차지하고 있으며, 연료전지는 친환경적이고 효율적인 에너지원으로서 근 미래의 새로운 대체 에너지로서 각광 받으며 여러 분야의 전기장치로 사용될 수 있다. 연료전지는 낮은 출력전압과 높은 출력전류를 갖는 특징이 있으며, 부하에 따라 출력전압이 변화하는 특성이 있기 때문에 연료전지의 사용을 위해서는 다양한 부하조건에서 연료전지와 연동된 승압 또는 강압형 컨버터의 제작이 반드시 필요하다. 본 논문에서는 DSP를 이용하여 컨버터의 디지털 제어가 가능하며, 고정 시비율로 동작하는 LLC 공진형 컨버터를 이용한 2kW급 연료전지용 양방향 컨버터를 제안하였다. 제안한 컨버터는 양방향으로 동작하며, 에너지 저장 및 재사용을 목적으로 하고, 출력은 24V 배터리가 된다.

• FLOWER RESEARCH JOURNAL
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• v.17 no.1
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• pp.29-35
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• 2009

The study was conducted to examine effective concentration and fertilization time of $CO_2$ for the growth of potted Phalaenopsis in growth chambers. Enrichment level of $CO_2$ was 1,000 or $2,000{\mu}mol{\cdot}mol^{-1}$ and fertilization time was 06:00~12:00, 00:00~06:00, or 18:00~24:00. Two, seven, or twelve month-old clonal micropropagules of Phalaenopsis cultivars were cultured for 99 days. Leaf number, leaf length, leaf width, root length and fresh weight of all Phalaenopsis cultivars in $2,000{\mu}mol{\cdot}mol^{-1}$ $CO_2$ were significantly greater than that of $1,000{\mu}mol{\cdot}mol^{-1}\;CO_2$. $CO_2$ fertilization time was the greatest growth in 0:00~06:00.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.3
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• pp.108-118
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• 2012

To investigate the responses of yellow poplar (Liriodendron tulipifera L.) seedlings to the interactive effects of the elevated atmospheric $CO_2$ level and nitrogen addition, we measured biomass, photosynthetic pigments, photosynthesis, and the contents of nitrogen (N) and carbon (C) from the seedlings after 16 weeks of the treatments. Yellow poplar seedlings were grown under the ambient ($400{\mu}mol\;mol^{-1}$) and the elevated (560 and $720{\mu}mol\;mol^{-1}$) CO2 concentratoins with three different N addition levels (1.2, 2.4, and $3.6g\;kg^{-1}$) in the Open Top Chambers (OTC). The dry weight of the seedlings enhanced with the increased N levels under the elevated $CO_2$ concentrations and the increment of the dry weight differed among the different N levels. Photosynthetic pigment content of the yellow poplar leaves also increased with the increase of the $CO_2$ concentration levels. The effects of the N levels on the photosynthetic pigment content, however, were significantly different among the $CO_2$ levels. Photosynthetic rates were affected by the levels of $CO_2$ and N concentrations. Stomatal conductance and transpiration rates increased with increasing $CO_2$ concentration. The carboxylation efficiency of the seedlings without N addition increased under the higher $CO_2$ concentrations whereas that with N addition decreased under the elevated $CO_2$ concentrations. Nitrogen and carbon uptake in leaf, stem, and root increased with the elevated $CO_2$ concentration level and N addition. In conclusion, under the elevated $CO_2$ concentrations, physiological characteristics and carbon uptake of the yellow poplar seedling were improved and increased with N addition.