• 설비공학논문집
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• 제16권9호
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• pp.863-871
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• 2004

The use of fossil fuels like coal, oil and natural gases around the world causes an increase of the carbon dioxide content in the atmosphere. In order to reduce the concentration of the greenhouse gas, the idea of carbon dioxide sequestration in the ocean is proposed to be an effective mitigation strategy to counteract potential global warming due to the greenhouse effect. Therefore, in the present study, calculations of the dissolution behavior of carbon dioxide when liquid carbon dioxide is released at 1,000m and 1,500m in depth by fixed pipeline are performed. The results show that carbon dioxide droplets change to carbon dioxide bubbles in gas phase around 500m in depth, and the droplets are completely dissolved below 500 m in depth if the liquide carbon dioxide is released both at 1,000 m in depth with the initial diameter of 0.007m or less and at 1,500m in depth with the diameter of 0.011m or less.

• Clinical and Experimental Pediatrics
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• 제55권10호
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• pp.359-366
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• 2012

Although most enterovirus infections are not serious enough to be life threatening, several enteroviruses such as enterovirus 71 are responsible for severe, potentially life-threatening disease. The epidemic patterns of enteroviruses occur regularly during the year, but they may change due to environmental shifts induced by climate change due to global warming. Therefore, enterovirus epidemiological studies should be performed continuously as a basis for anti-viral studies. A great number of synthesized antiviral compounds that work against enteroviruses have been developed but only a few have demonstrated effectiveness in vivo. No proven effective antiviral agents are available for enterovirus disease therapy. The development of a new antiviral drug is a difficult task due to poor selective toxicity and cost. To overcome these limitations, one approach is to accelerate the availability of other existing antiviral drugs approved for antiviral effect against enteroviruses, and the other way is to screen traditional medicinal plants.

• 세라미스트
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• 제22권2호
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• pp.182-188
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• 2019

Alternative energy sources to the systems using hydrocarbon fuels have been actively developed due to exhaustion of fossil fuels and issue of global warming by CO₂. Fuel cells have attracted great attentions to solve these issues as electricity can be produced with product of clean H₂O by using H₂-O₂ as a fuel. Besides, using reverse reactions make it possible to produce H₂ and O₂ gas from electrolysis of water. There are various fuel cells systems depending on the types of electrolyte, and in this mini-reviews, the main aim is to focus on perovskite oxides as a catalyst for oxygen-evolution reactions in alkaline electrolysis and its potential to application of alkaline electrolysis systems.

• Journal of Electrical Engineering and Technology
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• 제11권4호
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• pp.969-973
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• 2016

Interruption tests were conducted using the same circuit breaker for an initial pressure of SF₆ 0.5 MPa (gauge pressure) and CO₂ mixture 1.0 MPa, 0.8 MPa, and 0.6 MPa. The pressure-rises in the compression and thermal expansion chambers were measured for verifying the computational results using a simplified synthetic test facility. Further, the possibility of the CO₂ mixture substituting SF₆ gas was confirmed. Moreover, in view of the thermal recovery capability, it has also been confirmed that the pressure of the CO₂ mixture can be reduced almost to the same value as that of the SF₆ gas by optimizing the design parameters of the interrupter.

• 한국지열·수열에너지학회논문집
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• 제15권1호
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• pp.9-17
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• 2019

Reducing global warming potential has become important, and as one of those methods for reducing it, economic evaluation by applying ice thermal storage air conditioning system was performed. The floor area and height of the subject building was assumed $5,000m^2$ and 20 m. Absorption chillerheater system and air source heat pump system was used for comparing to the subject system, and payback period method was used to perform economic evaluation. Although the running cost of ice thermal storage system is reduced compared to two systems, the ratio is not significant compared to the increase of initial construction expenses, and payback period was calculated to be about 7.7 and 79.3 years. However, the heat storage system should be approached from the viewpoint of long term rather than the economic standard in the present standard.

• 한국기후변화학회지
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• 제7권3호
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• pp.325-334
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• 2016

We projected the distribution of Hedera rhombea, an evergreen broad-leaved climbing plant, under current climate conditions and predicted its future distributions under global warming. Inaddition, weexplained model uncertainty by employing 9 single Species Distribution model (SDM)s to model the distribution of Hedera rhombea. 9 single SDMs were constructed with 736 presence/absence data and 3 temperature and 3 precipitation data. Uncertainty of each SDM was assessed with TSS (Ture Skill Statistics) and AUC (the Area under the curve) value of ROC (receiver operating characteristic) analyses. To reduce model uncertainty, we combined 9 single SDMs weighted by TSS and resulted in an ensemble forecast, a TSS weighted ensemble. We predicted future distributions of Hedera rhombea under future climate conditions for the period of 2050 (2040~2060), which were estimated with HadGEM2-AO. RF (Random Forest), GBM (Generalized Boosted Model) and TSS weighted ensemble model showed higher prediction accuracies (AUC > 0.95, TSS > 0.80) than other SDMs. Based on the projections of TSS weighted ensemble, potential habitats under current climate conditions showed a discrepancy with actual habitats, especially in the northern distribution limit. The observed northern boundary of Hedera rhombea is Ulsan in the eastern Korean Peninsula, but the projected limit was eastern coast of Gangwon province. Geomorphological conditions and the dispersal limitations mediated by birds, the lack of bird habitats at eastern coast of Gangwon Province, account for such discrepancy. In general, potential habitats of Hedera rhombea expanded under future climate conditions, but the extent of expansions depend on RCP scenarios. Potential Habitat of Hedera rhombea expanded into Jeolla-inland area under RCP 4.5, and into Chungnam and Wonsan under RCP 8.5. Our results would be fundamental information for understanding the potential effects of climate change on the distribution of Hedera rhombea.

• 대한지구과학교육학회지
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• 제4권3호
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• pp.199-204
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• 2011

This study examines eighteen elementary teachers knowledge and teaching practrice of climate change using the KQEM survey, modified from the survey developed by Leiserowitz, A., Smith, N. & Marlon, J.R. (2010). The survey includes 11 questions from KQEM survey and 2 open ended questions about teachers' knowledge of climate change and their understandings of important climate change concept for elementary students. All of the participant teachers were purposefully selected for the study and were participated in the study volunteerly. The data for this study were analyzed both quantitatively and qualitatively. The result of this study indicates that the teachers have knowledge of climate change specifically about the topics of causes of climate change and consequences of climate change such as shifting biome and ecological impacts. While most of the teachers described climate change phenomena using scientific knowledge, some of the teachers (N=2) showed misconceptions about climate change phenomena. Most of the teachers thought the causes of climate change and potential solutions to reduce climate change are important concept that elementary students need to understand about climate change. Actually, most of the teachers are currently teaching the causes and consequences of climate change (N=13) potential solutions to global warming (N= 8). This study could inform teacher educators about what elementary teachers understand about climate change and what elementary teachers are currently teaching about climate change.

• 에너지공학
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• 제11권2호
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• pp.106-113
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• 2002

급격히 증가하는 에너지 수요에 비해, 현재 주에너지원인 화석에너지나 원자력은 지구 온난화 및 핵폐기물 등의 환경오염 문제로 인해 그 공급을 계속적으로 증가시키는 데에는 많은 제약을 받고 있다. 이러한 에너지 공급의 한계를 극복하기 위해서는 풍부한 자연에너지를 활용할 필요가 있는데, 최근의 열펌프 기술의 발전과 더불어 하천수·해수 하수처리수 등의 온도차에너지에 대한 미활용에너지의 활용지술의 기대가 크게 증가되고 있다. 따라서 미활용에너지의 활용을 위한 기초자료를 확보하기 위하여 열원별·지역별 미활용에너지의 부존량 및 이용가능량을 조사·산정하고, 미활용에너지의 이용가능성에 대하여 평가하였다.

• 펄프종이기술
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• 제36권1호
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• pp.49-60
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• 2004

Life Cycle Assessment for the pulp, which is mainly used as the raw material of fine paper, base paper for food packaging and paper cup, has been carried out in this study to consider environmental aspects by quantifying the environmental emission and to evaluate its environmental impact potential. The system boundary was selected from cradle to gate stage(raw material acquisition, transportation of raw material and product manufacturing) of the product. Environmental impact was divided into 8 categories considering Korean situation: abiotic resource depletion, global warming, ozone depletion, acidification, eutrophication, photochemical oxidant creation, ecotoxicity and human toxicity. In Life Cycle Impact Assessment(LCIA) methodology phase, Ecopoint, Eco-indicator 95 and Korean eco-indicator were used and the results carried out by each methodology were compared. The results from this study were also compared with those of foreign study to verify the reliability of the results. The results of the study could be utilized as the basic data for Environmental Management System(EMS), Design for Environment(DfE) and Type III eco-labeling in the paper and paper-related industry.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.564-568
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• 2007

Gas hydrate has been attractive topic for two dedicates because it may cause the global warming, ocean hazards associated with the instability of marine slope due to the gas hydrate release as well as high potential of future energy resources. The study on gas hydrate in Ulleung basin has been performed since 1999 to explore the potential and distribution of gas hydrate offshore Korea. The numerous multi channel seismic data have been acquired and processed by Korea Institute of Geosciences and Mineral Resources (KIGAM). The results showed clearly the gas hydrate indicators such as pull up structure, bottom simulating reflector (BSR), seismic blanking zone. The prestack depth migration has been considered as fast and accurate technique to image the subsurface. In this paper, we will present both the conventional seismic data processing and apply Kirchhoff prestack depth migration for gas hydrate data set. The results will be applied for core sample collections and for proposal more detail 2D with long offset or 3D seismic exploration.