• 한국환경과학회지
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• 제21권2호
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• pp.165-179
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• 2012

Indirect $CO_2$ effect due to non-methane volatile organic compound (NMVOC) emissions from solvent and product use and fugitive NMVOC emissions from fuels in the Republic of Korea and 13 Annex I countries under United Nations Framework on Climate Change were estimated and the proportions of them to total greenhouse gas (GHG) emissions ranged from 0.092% to 0.45% in 2006. Indirect greenhouse effect ($CO_2$, $CH_4$, and $O_3$) were estimated at 13 photochemical assessment monitoring sites in the Republic of Korea using concentrations of 8 NMVOCs of which indirect global warming potential (GWP) were available. The contribution of toluene to mixing ratio was highest at 11 sites and however, the contribution of toluene to indirect greenhouse effect was highest at nine sites. In contrast to toluene, the contributions of ethane, butane, and ethylene were enhanced. The indirect greenhouse effects of ethane and propane, of which ozone formation potentials are the lowest and the third lowest respectively among targeted 10 NMVOCs, ranked first and fourth highest respectively. Acetaldehyde has relatively higher maximum incremental reactivity and is classified as probable human carcinogen however, its indirect GWP ranked second lowest.

• 설비공학논문집
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• 제26권11호
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• pp.547-552
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• 2014

As global warming in recent years has raised ever more critical concern, refrigerants with high global warming potentials (GWP) are facing the challenge of being phased out. R410A, with a GWP of 2,088, has been widely used in residential air-conditioning and heat pump systems. A potential substitute for R410A is R32, which has a GWP of 675. The present study presents experimental results of an inverter heat pump system that uses R32 as an alternative refrigerant to R410A. Drop-in tests with R32 indicated that the energy efficiency ratio of the system increased by 5.3% in cooling standard mode, and by 4.2% in heating standard mode at the same capacity; and that the cooling and heating capacity increased by about 12% at the same compressor operating frequency, while the annual performance factor (APF) of the system increased by 5.3%.

• 한국대기환경학회지
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• 제30권4호
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• pp.387-397
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• 2014

This work aims at estimating global warming potentials (GWP) of $CF_3Br$ and HFC-134a among green house gases. It has been reported that they have much higher GWP than $CO_2$ in the atmosphere. $CF_3Br$, halon 1301 which is well known to be a fire extinguisher, as one of the bromine-containing halons has been banned since 2003 due to destruction of ozone. HFCs, a kind of chiller which replaced chlorofluorocarbons (CFCs) are one of greenhouse gases regulated by the Kyoto Protocol. In this study, we produced GWPs of $CF_3Br$ and HFC-134a by calculating a life time and measuring an absorption cross section to obtain a radiative forcing (RF). Their absorption cross sections were measured by using Fourier-transformed infrared spectroscopy (FTS) with a gas cell filled with their certified reference materials at room temperature. As a result, the RFs of $CF_3Br$ and HFC-134a were 0.32 and $0.168Wm^{-2}ppb^{-1}$, respectively and the GWPs were calculated as 7989, 6076, 3903 for $CF_3Br$ and 3855, 1300, 656 for HFC-134a for the time horizon of 20, 100, 500 years, respectively. Overall, uncertainty of the estimated GWPs can be estimated to be about 2.6%. Our results were compared with those proposed by the previous studies (IPCC, 2007; WMO, 1999).

• 한국지열·수열에너지학회논문집
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• 제13권4호
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• pp.14-20
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• 2017

Refrigerant having high global warming potentials will be phased out due to environmental protection issues. R410A has been widely used in geothermal heat pump. However, it has a little high GWP by 2088 value. One of the recommended substitute for R410A refrigerant is R452B which having a GWP by 698 value. In this paper, the heating and cooling performance of the water-to-water geothermal heat pump unit with R452B was experimentally investigated. The performance of the heat pump adopting R452B was also compared with the system applying R410A. The heating and cooling capacity of R452B heat pump system showed a slightly lower values within 2% comparing with R410A system. However, the R452B system's coefficient of performance was enhanced by 5.2% and 13.7% at heating and cooling mode, respectively.

• 한국토양비료학회지
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• 제36권4호
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• pp.256-262
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• 2003

밭벼와 콩 재배지에서 메탄과 아산화질소 배출을 측정하였다. 2001년 4월 28일 폭 30 cm 간격으로 대진벼를 파종하였다. 포장의 물관리는 스프링클러 관개와 천연강우 관개로 하였다. 콩 품종 장엽콩, 태광콩, 황금콩을 2001년 6월 16일에 $60{\times}15cm$ 간격으로 한 구멍에 2알씩 파종하였다. 기체시료는 주 2회씩 채취하여 메탄과 아산화질소를 분석하였다. 밭벼 작기중 메탄 배출은 스프링클러 관개구에서 $3.5kg\;CH_4\;ha^{-1}$ 였었고 천연관개구에서 $-1.7kg\;CH_4\;ha^{-1}$ 였었다. 밭벼 작기중 아산화질소 배출은 스프링클러 관개구에서 $50.8kg\;N_2O\;ha^{-1}$ 였었고 천연관개구에서 $8.3kg\;N_2O\;ha^{-1}$ 였었다. 밭벼 재배지에서 배출하는 온실가스 GWP는 스프링클러 관개구와 천연관개구에서 각각 15,822 및 $2,216kg\;CO_2\;ha^{-1}$ 였었다. 콩 작기중 메탄 배출은 장엽콩 재배구에서 $-14.7kg\;CH_4\;ha^{-1}$ 였었고 태광콩 재배구에서 $-4.3kg\;CH_4\;ha^{-1}$, 황금콩 재배구에서 $4.8kg\;CH_4\;ha^{-1}$ 였었다. 콩 작기중 아산화질소 배출은 장엽콩 재배구에서 $4.7kg\;N_2O\;ha^{-1}$, 태광콩 재배구에서 $4.6kg\;N_2O\;ha^{-1}$, 그리고 황금콩 재배구에서 $3.0kg\;N_2O\;ha^{-1}$ 였었다. 콩 작기중 배출하는 온실가스 GWP는 장엽콩, 태광콩, 황금콩 재배구에서 각각 1,152, 1,323 및 $1,027kg\;CO_2\;ha^{-1}$ 였었다.