• 수산해양기술연구
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• 제45권2호
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• pp.114-121
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• 2009

There are increased in using the bio-ethanol, as the carbon neutral attracts many researchers due to a reduction in carbon dioxide spotted as the global warming gas. A gasoline engine with 100% of the bioethanol was developed and used in Brazil already, but researches of using the bio-ethanol in diesel engines are lack. In this study, combustion tests with blend fuel of the gas oil and bio ethanol by 50% maximally due to a low cetane number of bio-ethanol were accomplished as a basic study of introduction of using the bioethanol in diesel engines. The result was that smoke emission was decreased with increase in proportion of the bio-ethanol, due to the increase of a amount of pre-mixed combustion with ignition delay. Although the amount of $CO_2$ is reduced according as the bio-ethanol is used(carbon neutral), the emission of $CO_2$ with increase in the proportion of the bio-ethanol was more increased due to lower a heat value of bio-ethanol than gas oil.

• 한국조경학회지
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• 제27권5호
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• pp.38-47
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• 2000

Carbon dioxide is a major greenhouse gas causing climate change. This study quantified annual direct and indirect uptake of carbon by urban greenspace, and annual carbon release from vegetation maintenance and fossil fuel consumption. The study area was whole Chuncheon and Kangleung, and also two districts of Kangnam and Junglang in Seoul, cities located in middle Korea. Carbon uptake by urban greenspace played an important role through offsetting carbon release by 6-7% annually in Chuncheon and Kangleung. For Kangnam and Junglang, where the population density was relatively higher, urban greenspace annually offset carbon release by 1-2%. Future possible tree plantings could double annual carbon uptake by existing trees in urban lands (except natural and agricultural lands) of a study city. Based on study results, planning and management guidelines for urban greenspace were suggested to save energy and to reduce atmospheric $CO_2$ concentrations. They included selection of optimum tree species, proper planting location from buildings, design of multilayered planting, amendment of existing regulations for greenspace enlargement, avoidance f intensive vegetation maintenance, and conservation of natural vegetation.

• 환경영향평가
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• 제17권3호
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• pp.201-211
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• 2008

According to IPCC fourth assessment report in 2007, global mean temperatures have risen by 0.74 degrees Celsius over the past 100 years. Moreover, in the recent 25 years, global mean temperatures have risen by 0.45 degrees Celsius, which is 2.4-times larger than those in the past 100 years. The evidences for climate change, such as sea level rise, arctic glacier melt, and desertification in Asia, have occurred and increased over the globe. In Korea, because regional climate has been changed, types of agriculture and fishery should be replaced. And as precipitation pattern behave differently from the past decades, water management would be more difficult, furthermore, atmospheric environment, related to concentrations for ozone, sulfate, etc., could be worse. Nevertheless, we have only focused on greenhouse gas reduction duty for the Convention of Climate Change. Fortunately, in the fourth plan on climate change, we have planned to manage climate change more actively since 2007. In Korea, the emission of carbon dioxide has increased about 1.9-times more, from 311million ton in 1990 to 591million ton in 2004. And also about 2 ppm rise every year for concentrations of carbon dioxide in the atmosphere. As a result, ecosystem, quality of water and atmosphere would be affected. Here, the emission of greenhouse gases over the globe is examined, and the effect of greenhouse gases for climate change is reviewed from the results of previous studies. In addition, the countermeasures of mitigation and adaptation on climate change were discussed for the understanding.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.119-124
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• 2000

We hypothesized that the extent of hypoxic injury would be involved in reduction of oxygen delivery to the tissue. Livers isolated from 18 hr-fasted rats were subjected to $N_2$-induced hypoxia or low flow hypoxia. Livers were perfused with nitrogen/carbon dioxide gas for 45min or perfused with normoxic Krebs-Henseleit bicarbonate buffer (KHBB) at low flow rates around 1 ml/g liver/min far 45min, which caused cells to become hypoxic because of insufficient delivery of oxygen. When normal flow rates(4 ml/g liver/min) of KHBB (pH 7.4, 37$^{\circ}C$, oxygen/carbon dioxide gas) were restored for 30min reoxygenation injury occurred. Lactate dehydrogenase release gradually increased in $N_2$-induced hypoxia, whereas it rapidly increased in low flow hypoxia. Total glutathione in liver tissue was not changed but oxidized glutathione markedly increased after hypoxia and reoxygenation, expecially in $N_2$-induced hypoxia. Similarly, lipid peroxidation in liver tissue significantly increased after hypoxia and reoxygenation in low flow hypoxia. Hepatic drug metabolizing functions (phase I, II) were suppressed during hypoxia, especially in $N_2$-induced hypoxia but improved by reoxygenation in both models. Our findings suggest that hypoxia results in abnormalities in drug metabolizing function caused by oxidative stress and that this injury is dependent on hypoxic conditions.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.745-751
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• 2009

The anchor is used extensively for a cutting slope, an earth retaining wall, an uplift resistance of sub-structures and so on at civil engineering projects and is classified by aim in use, tendon material, and ground/tension fixing type. It can be distinguished extensively into friction type, bearing type, and complex type by ground fixing type. Generally, bond length of friction type anchor has application to 3~10m depending on the friction-resistance characteristics. In this study, 'DEW(double enlargement wedge) bearing type anchor' of new concept is devised. The bond length is about 0.6~0.8m. It can be used on the ground to have the strength characteristics above it of weathered rock. There are merits which are 'period reduction' and 'cost saving' through the minimum of the boring length. In addition, it is so called environmentally friendly Methods because it can reduce the quantity of carbon dioxide through the reducing drilling machine operation time.

• KIEAE Journal
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• 제12권6호
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• pp.39-47
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• 2012

Recently, the green building and energy connection system are establishing. But, National certification system for environment-Friendly Buildings is indicated hangup about energy efficiency of building. Commissioning, energy conservation, renewable energy, carbon dioxide emissions, it is determined that the energy associated with LEED and GBCC four items of the comparative analysis showed the following results. First, on the practical performance of the system after the completion of commissioning of the energy associated with the system completed until after the final performance for secure operation from the planning stage to verify and document systematically how to perform, but the domestic review and verification is incomplete. Second, the use of energy-saving and renewable energy is directly related to the energy consumption of the building, but GBCC the strengthening of standards on how to evaluate it is deemed necessary. Finally, the evaluation of the reduction of carbon dioxide emissions, LEED Unlike GBCC the life-cycle of the system without considering the global warming index only because a substantial step in the operating efficiency can not be assessed. Based on this study GBCC energy savings through efficiency to actively carry out research through a systematic analysis of the basic guidelines to proceed.

• Journal of Animal Science and Technology
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• 제61권3호
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• pp.122-137
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• 2019

Methane, one of the important greenhouse gas, has a higher global warming potential than that of carbon dioxide. Agriculture, especially livestock, is considered as the biggest sector in producing anthropogenic methane. Among livestock, ruminants are the highest emitters of enteric methane. Methanogenesis, a continuous process in the rumen, carried out by archaea either with a hydrogenotrophic pathway that converts hydrogen and carbon dioxide to methane or with methylotrophic pathway, which the substrate for methanogenesis is methyl groups. For accurate estimation of methane from ruminants, three methods have been successfully used in various experiments under different environmental conditions such as respiration chamber, sulfur hexafluoride tracer technique, and the automated head-chamber or GreenFeed system. Methane production and emission from ruminants are increasing day by day with an increase of ruminants which help to meet up the nutrient demands of the increasing human population throughout the world. Several mitigation strategies have been taken separately for methane abatement from ruminant productions such as animal intervention, diet selection, dietary feed additives, probiotics, defaunation, supplementation of fats, oils, organic acids, plant secondary metabolites, etc. However, sustainable mitigation strategies are not established yet. A cumulative approach of accurate enteric methane measurement and existing mitigation strategies with more focusing on the biological reduction of methane emission by direct-fed microbials could be the sustainable methane mitigation approaches.

• Asian Journal of Business Environment
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• 제11권1호
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• pp.39-50
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• 2021

Purpose: This study seeks to establish the environmental damage theory applicable to Kenya. The analysis is based on annual data drawn from World Bank on carbon dioxide emissions (CO2e) and gross domestic product per capita (GDPPC) for Kenya spanning 1963 to 2017. Research Methodology: The study adopts explanatory research design and autoregressive distributed lag model for analysis. Results: The results revealed a coefficient of -0.017 for GDPPC and 0.004 for GDPPC squared indicating that economic growth has negative effect on CO2e in the initial stages of growth but positive effect in the high growth regime with the marginal effect being higher in the initial growth regime. The findings suggest a U-shaped relationship consistent with Brundtland Curve Hypothesis (BCH). Conclusions: The findings emphasize the need for sustainable development path that enables present generations to meet own needs without compromising the capacity of future generations to meet their own. Sustainable development may include, investment in renewable energies like wind, solar and adoption of energy efficient technologies in production and manufacturing. The study concludes that BCH is applicable to Kenya and that developing affordable and effective mechanisms to boost sustainable development implementation is necessary to decrease the anthropogenic impact in the environment without any attendant reduction in the economic growth.

• 공업화학전망
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• 제23권4호
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• pp.1-12
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• 2020

최근 실내 공기질(IAQ; indoor air quality)을 악화시키는 물질 중 하나인 이산화탄소 저감 연구가 다수 진행되고 있다. 현재 이산화탄소를 저감하는 방법에는 흡착법, 흡수법, 막분리법 등이 있다. 그 중 흡수법은 액체 상태의 흡수제를 분사하는 공정 특성상 실내에 적용하기 어렵고 2차 오염물 또는 폐수가 발생할 수 있다. 또한, 막분리법은 이산화탄소 분리를 위한 응집 및 침전과 같은 전처리 과정이 필요하므로 실내 이산화탄소 저감에 적합하지 않다. 반면, 흡착법은 비교적 저렴하고 운영이 간단하여 적용 사례가 증가하였으며, 유동 인구가 많고 환기가 어려운 지하철, 버스 등의 대중교통 차량 내부 및 교실, 사무실, 공공시설에서 배출되는 실내 이산화탄소를 제어할 수 있다는 장점이 있어 가장 적합한 해결책으로 알려져 있다. 흡착 공정에 사용되는 대표적인 흡착제 종류에는 활성탄, 제올라이트, 알루미나 등이 있으며, 이 흡착제들을 개질 및 성형하여 흡착제의 성능 및 기계적 강도를 증진시키는 고도화 연구가 활발히 수행되고 있다. 이처럼 적용 대상 내 설치 및 교체가 용이하도록 하는 흡착제 제조 기술 개발이 필요한 실정이며, 흡착제를 상용화 수준까지 발전시킴으로써 강화된 실내 공기질 규제 기준에 대한 대응 및 삶의 질 향상이 기대된다.

• 무역학회지
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• 제47권1호
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• pp.1-12
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• 2022

This study analyzes FCEV among measures to respond to climate change policies. In particular, it proposes alternatives to solve this problem in the trade industry, which relies on transportation sectors with high greenhouse gas emissions such as exports and imports of goods. Therefore, when FCEV is introduced in the transportation sector, changes in CO2 emissions, a greenhouse gas, and changes in logistics costs for changes in CO2 emissions are set through scenarios to evaluate the impact on product trade, such as imports and exports. As a result, the increase in logistics costs due to carbon dioxide emissions affected the import and export volume of goods, and when FCEV was introduced, the export volume would increase by up to 5.6%, and the import volume by up to 30%. In addition, CO2 emissions decreased to about 60% in 2050. Therefore, the introduction of FCEV in the transportation sector will greatly contribute to increasing sales in the trading industry and will be able to solve environmental problems such as greenhouse gas reduction.