• 한국대기환경학회지
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• 제31권4호
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• pp.356-367
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• 2015

A consumption based study on the carbon dioxide ($CO_2$) emission change due to the changes in the bovine meat consumption behavior in Korea was carried out. It was found that if the consumption of bovine meat be reduced by half, the reduction amount of $CO_2$ emissions be over 0.8 $MtCO_2e$ in all senarios in 2023. This amount is equivalent to over 50% of the greenhouse gases (GHGs) emission reduction target in agriculture and forestry, and fishery, a significant reduction. It was also found that the $CO_2$ emission reduction amount in consumption-based approach was the largest when the consumption of the imported bovine meat be reduced, though the difference was not that large.

• 한국환경과학회지
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• 제25권1호
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• pp.23-29
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• 2016

This study has conducted greenhouse gas emission reduction test as using Oyster-shells originated PCC paper filler compare to non-Oyster shells used PCC. This examination was estimated and calculated in accordance with both IPCC (Intergovernmental Panel on Climate Change) and World Business Council for Sustainable Development (WBSCD). The greenhouse gas emission reduction estimation result indicates that, when oyster shells are recycled and used as paper filler, it reduces $27.97tCO_2\;per\;100\;ton$ of oyster shells. It is greenhouse gas emission $44.27tCO_2$ from PCC production changed to carbon emission reduction when replaced with oyster shell. LNG greenhouse gas emission $16.3tCO_2$ in relation to the pre-treatment with oyster shell per 100 ton is also reflected. As a result, it is assumed that roughly $0.2797tCO_2/oyster\;shell{\cdot}ton$.

• Journal of Photoscience
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• 제2권1호
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• pp.13-18
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• 1995

The steady-state emission spectra of dicoumarol (DC) in ethanol and EPA have been examined at various temperatures (77-298 K). At room temperature, a fluorescence spectrum of DC in ethanol shows a emission maximum at 350 nm. In EPA a Stokes-shifted emission band appears around 470 nm in addition to the 350 nm emission, and its intensity is enhanced as temperature decreases. This emission is attributed to a zwitterionic tautomer of DC formed by a single excited-state intramolecular proton transfer (ESIPT) along the internal hydrogen-bonding. The fluorescence lifetimes have been measured at 350 and 450 nm as a function of temperature. The fluorescence decay at 350 nm is single exponential at any temperature, whereas the one at 450 nm becomes biexponential at temperatures below 250 K. These results are discussed in terms of a conformational change followed by the ESIPT. The activation energy barrier for the conformational change has been determined to be 3.7 $\pm$ 0.2 kJ/mole.

• 한국자동차공학회논문집
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• 제21권4호
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• pp.106-112
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• 2013

Compression ratio is an important factor affecting engine performance and emission characteristics since thermal efficiency of spark ignition engine can be theoretically improved by increasing compression ratio. In order to evaluate the effect of compression ratio change in HCNG engine, natural gas engine was employed using HCNG30 (CNG 70 vol%, hydrogen 30 vol%). Combustion and emission characteristics of CNG and HCNG fuel was analyzed with respect to the change of compression ratio at each operating condition. The results showed that thermal efficiency improved and $CH_4$, $CO_2$ emission decreased with the increase in compression ratio while $NO_x$ emissions were decreased at a certain excess air ratio condition. Higher thermal efficiency and further reduction of exhaust emissions can be achieved by the increase of compression ratio and the retard of spark timing.

• 한국기후변화학회지
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• 제5권4호
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• pp.359-366
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• 2014

This research was conducted to estimate methane emission from paddy field of 16 local government levels using the DNDC(DeNitrification-DeComposition) model from 1990 to 2010. Four treatments used in DNDC model for methane emission calculations were (1) midseason drainage with rice straw, (2) midseason drainage without rice straw, (3) continuous flooding with rice straw, and (4) continuous flooding without rice straw. Methane emissions at continuous flooding with rice straw were the highest ($471kg\;C\;ha^{-1}$) while were the lowest ($187kg\;C\;ha^{-1}$) at midseason drainage without rice straw. The average methane emission for 21 years was the highest ($1,406Gg\;CO_{2-eq}$.) in Jeonnam province because of its large cultivation area. Jeju province had the highest the average methane emission per unit area due to the organic content in soil.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.411-412
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• 2007

EL (electro luminescent) is generally studied as a large size plane light emitting device and flexible light source because of it's simple manufacturing process. In this experiment, we manufactured flexible white emitting light source using Ni-foil with blue phosphor and color change materials. With increasing the thickness of color change material, the luminance of white emission is increased and the color coordinate of white color was shifted to pure white of (0.317,0.328) by strong emission of color change materials excited by blue excitation spectra. Also the luminance level was 30% higher in white emitting light device than blue only light source.

• 대한금속재료학회지
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• 제49권9호
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• pp.732-738
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• 2011

Silicon oxide thin films were deposited by using a plasma-enhanced chemical-vapor deposition technique to investigate the light emission properties. The photoluminescence characteristics were divided into two categories along the relative ratio of the flow rates of $SiH_4$ and $N_2O$ source gases, which show light emission in the broad/visible range and a light emission peak at 380 nm. We attribute the broad/visible light emission and the light emission peak to the quantum confinement effect of nanocrystalline silicon and the Si=O defects, respectively. Changes in the photoluminescence spectra were observed after the post-annealing processes. The photoluminescence spectra of the broad light emission in the visible range shifted to the long wavelength and were saturated above an annealing temperature of $900^{\circ}C$ or after 1 hour annealing at $970^{\circ}C$. However, the position of the light emission peak at 380 nm did not change at all after the post-annealing processes. The light emission intensities at 380 nm initially increased, and decreased at annealing temperatures above $700^{\circ}C$ or after 1 hour annealing at $700^{\circ}C$. The photoluminescence behaviors after the annealing processes can be explained bythe size change of the nanocrystalline silicon and the density change of Si=O defect in the films, respectively. These results support the possibility of using a silicon-based light source for Si-optoelectronic integrated circuits and/or display devices.

• 한국환경농학회지
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• 제40권4호
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• pp.366-372
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• 2021

BACKGROUND: Ammonia is known as a precursor to fine particulate matter, and according to CAPSS, annual ammonia emissions in the agricultural sector were 249,777 tons as of 2018, accounting for about 79.0% of Korea's total ammonia emissions. In particular, ammonia emissions from agricultural land increased by 19,566 tons (10.2%) compared to the previous year. The Ministry of Environment is setting emission statistics using the ammonia emission coefficient developed in Korea in 2008, but researchers in the agricultural field regard it as a coefficient that does not reflect the reality of Korea's agricultural environment. Accordingly, in order to develop ammonia emission coefficients from the cultivation of apples and pears, Korea's representative fruit type, test agricultural land was set in Iksan, Jeollabuk-do. METHODS AND RESULTS: This study attempted to obtain the ammonia emission coefficient by the treatment of the composite fertilizer (N-P₂O₅-K₂O=12-7-9), and the flux was measured using a dynamic flow-through chamber method. As for the chamber, a total of 12 chambers were installed repeatedly in 4 zones and used to develop emission coefficients. Using compound fertilizers during fruit tree cultivation, the ammonia emission coefficient was evaluated as 10.4 kg NH3/ton for pears and 15.3 kg NH₃/ton for apples. The reason why the ammonia emission coefficient according to the use of composite fertilizers was calculated higher for apple cultivation is believed to be due to the relatively high pH concentration of apple orchard soil. CONCLUSION(S): This study may provide basic data for upgrading the ammonia emission coefficient when using composite fertilizers in agricultural land. In the future, it might be necessary to upgrade the calculation of emissions through the development of ammonia and fine particulate matter emission coefficients considering the agricultural environment of Korea.

• 한국기후변화학회지
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• 제8권4호
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• pp.393-399
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• 2017

According to the United Nations Framework Convention on Climate Change (UNFCCC), all parties have to submit the national GHG inventory report. Estimating carbon stocks and changes in Land Use, Land-Use Changes and Forestry (LULUCF) needs an activity data and emission factors. So this study was conducted to develop carbon emission factor for Robinia pseudoacacia L., Betula platyphylla var. japonica, and Liriodendron tulipifera. As a result, the basic wood density ($g/cm_3$) was 0.64 for R. pseudoacacia, 0.55 for B. platyphylla, and 0.46 for L. tulipifera. Biomass expansion factor was 1.47 for R. pseudoacacia, 1.30 for B. platyphylla, and 1.24 for L. tulipifera. Root to shoot ratio was 0.48 for R. pseudoacacia, 0.29 for B. platyphylla, and 0.23 for L. tulipifera. Uncertainty of estimated emission factors on three species ranged from 3.39% to 27.43% within recommended value (30%) by IPCC. We calculated carbon stock and change using these emission factors. Three species stored carbon in forest and net $CO_2$ removal was $1,255,398\;t\;CO_2/yr$ during 5 years. So we concluded that our result could be used as emission factors for national GHG inventory report on forest sector.

• 한국해양환경ㆍ에너지학회지
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• 제4권4호
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• pp.42-50
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• 2001

본 논문에서는 수출입컨테이너 화물의 육상운송에서 연안운송으로의 전환을 이용한 CO₂가스 및 배기가스 배출량 삭감이 제안되어진다. 먼저 국내의 CO₂가스 배출량, 배기가스 배출량, 수출입컨테이너화물의 물동량 등에 대하여 간단히 살펴본다. 또한 경인지역과 부산항사이의 수출입컨테이너화물 수송에 대하여 육상운송에서 연안운송으로의 변환에 의한 CO₂가스 및 배기가스 배출량 삭감효과에 대하여 고찰한다. 마지막으로 연안운송의 분담율 변화와 320TEU 소형컨테이너선 이용에 따른 NOx가스 배출량 변화를 고찰한다. 본 연구의 결과 육상운송에서 연안운송으로의 전환이 CO₂가스 및 배기가스 배출량 삭감에 효과적인 것을 확인하였다.