• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4D
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• pp.603-611
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• 2011

After Kyoto Protocol was adopted for green gas reduction, each nations are stepping up efforts to reduce $CO_2$ of a typical green gas. Construction industry also is trying $CO_2$ reduction with the techniques of two types which are software and hardware techniques. The software technique are Passive Design considered green gas emission and the environment impact assessment by LCA. The hardware techniques are adjustment of equipment system and development of eco- friendly material. But, it is nonexistent that a study related to $CO_2$ emission considered detail process in construction industry. This study analyzed the correlation of equipment combination, $CO_2$ emission and duration by calculate $CO_2$ emission follow to equipment combination on earth-work which is the process emitted most $CO_2$ among railway bedding construction.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.6
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• pp.393-398
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• 2008

Several researchers have proposed models or equations to predict soil $CO_2$ flux from more readily available biotic and abiotic measurement. Tree commonly used abiotic variables were N mineral and soil temperature and soil water content. This study was conducted to determine $CO_2$ emission to mineral N, soil water content and soil temperature with clay loam and sandy loam in pepper cultivation in 2004~2005. $CO_2$ flux in the upland with different levels of soil water potential was measured at least once in two weeks during the cropping period in the pepper cultivation plots. Soil water potential in the clay loam and sandy loam soils was established at -30kPa and -50kPa by measuring the soil gravimetric water content with two replications. $CO_2$ emission rate from the differently managed plots was highly correlation coefficient to between the mineral N ($R=0.830^{**}$, $0.876^{**}$) and soil temperature ($r^2=0.793^{**}$, $0.804^{**}$) in the clay loam and sandy loam, respectively. However, the relationships between $CO_2$ emission and soil water content were non-significant. $CO_2$ emissions at sandy loam soils was lower to 21~37% than at clay loam soils for both soil water conditions without differences in yield. At difference levels of soil water conditions, $CO_2$ emission at -50kPa decreased to 37.5% in comparison with that at -30kPa. From the path analysis as to contribution factors of GHGs, it appeared that contribution rate was in the order of soil temperature (54.9%), mineral N (32.7%), and soil moisture content (12.4%).

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.1
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• pp.80-87
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• 2011

Blast furnance slag cement is a cement manufactured with using industrial by-product and it can reduce $CO_2$ by replacing cement when same uit volume concrete is produced. But Blast furnance slag has a short point that early strength of concrete is not good in winter season and it can be used. So, in this study, as long as replacement ratio of Blast furnance slag to original portland cement is under 30%, developed cement, ecoment, improve early strength of concrete and it applied to constructoin site. As a result, it improves 37% in terms of 1-day strength, it reduces 6.7% in terms of $CO_2$ emission when $1m^3$ concrete was produced. The importance and applicability of study wll be expected to increase cosidering global effort and green growth-strategy in country for reducing greenhouse gases.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.1
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• pp.1-8
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• 2023

In this study, to reduce CO₂ emission in the cement manufacturing process, we evaluated the limestone that is used as a raw material for cement, substituted with steel slag by the various substituted levels. Based on the chemical composition of each raw materials including limestone, and blast furnace slow cooling slag, converter slag, and KR slag as an alternative raw material, we simulated the optimal cement raw mixture by the substitution levels of limestone. Test results indicated that the steel slags contain a certain level of CaO that can be used as alternative decarbonated raw materials, and it has enough to partially reduce the amount of limestonem. And we estimated the maximum usable levels of each raw material. In particular, it was confirmed that by using a mixture of these raw materials rather than using them one by one, the effect of reducing limestone was increased and CO₂ emission from the cement manufacturing process could be reduced.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.297-304
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• 2013

Due to its excessive $CO_2$ emissions, road transport sector becomes a target for emission reduction strategies. Although precise and reliable emissions inventories are necessary for evaluating plans and strategies, developing the region-wide inventory is a difficult task mainly because of a lack of data including travel patterns and modal volumes in the reginonal context. Most existing inventory methodologies employ fuel sale data within the target region, which ignores actual regional traffic patterns and thus not suited to its geographical context. To overcome these problems, this study develops region-wide $CO_2$ emissions inventory methodology by utilizing the Korea Transport DB (KTDB). KTDB provides a number of useful information and data, such as road network with which one can identify in and out trips over the entire region, traffic volumes of various modes, distance of travel, travel speed and so on. A model of equations that allow the computation of volume of $CO_2$ emitting from the road transport activities within the target region is developed. Using the model, numerical analyses are performed for the case of Busan Metropolitan City to demonstrate the applicability of the developed model. This study is indeed exploratory in the sense that using the existing data, it develops the $CO_2$ emissions inventory methodology which can produce better results than those from conventional fuel sales methodology. This study also suggests further reresarch directions to develop more refined methodologies in region-wide basis.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.248-249
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• 1999

지구온난화의 주요 주범인 $CO_2$의 감축을 위해 자동차 연비 및 배출허용기준등을 전 세계적으로 강화하고 있으며 이에따라 선진국에서는 Super Car 및 3L Car Project등을 통해 초저연비자동차 개발을 추진하고 있다. 이런 추세에 따라 압축비가 높아 연소효율이 좋고 연표경제성이 가솔린엔진보다 우수한 경유엔진은 $CO_2$ 배출이 적어 향후 그 보급이 더욱 확대될 것으로 기대되고 있다.(중략)

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.177-184
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• 2011

There are several differences between freeways and general national roads in terms of structures, conditions and limited speeds. Likewise, the characteristics of $CO_2$ emission in these roads differ depending on the road types. For these reasons, it is necessary to compare the two types of roads in terms of $CO_2$ emissions. The study was performed targeting Gyeongbu Expressway and National Highway 1. Firstly, the amount of $CO_2$ emission each car was compared in the whole sections of the both. Secondly, top 10 sections were picked out, and then $CO_2$ emission each section were compared. Lastly, two sections which were with the highest and lowest amount of $CO_2$ emission per car, were compared. As results, it were found that there were less amount of $CO_2$ emission on freeways. because cars are running on uniform velocity at relatively high speed, and that there were more amount of $CO_2$ emission on the national highway. because of frequent intersections and associated congestion. It may be concluded that the amount of $CO_2$ emission at the national highway could be reduced if signal coordination and intersection intervals are improved there.

• Clean Technology
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• v.28 no.1
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• pp.9-17
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• 2022

Electrochemical carbon dioxide (CO₂) reduction technology, one of the promising solutions for climate change, can convert CO₂, a representative greenhouse gas (GHG), into valuable base chemicals using electric energy. In particular, carbon monoxide (CO), among various candidate products, is attracting much attention from both academia and industry because of its high Faraday efficiency, promising economic feasibility, and relatively large market size. Although numerous previous studies have recently analyzed the GHG reduction potential of this technology, the assumptions made and inventory data used are neither consistent nor transparent. In this study, a comparative life cycle assessment was carried out to analyze the potential for reducing GHG emissions in the electrochemical CO production process in a more transparent way. By defining three different system boundaries, the global warming impact was compared with that of a fossil fuel-based CO production process. The results confirmed that the emission factor of electric energy supplied to CO₂-electrolyzers should be much lower than that of the current national power generation sector in order to mitigate GHG emissions by replacing conventional CO production with electrochemical CO production. Also, it is important to disclose transparently inventory data of the conventional CO production process for a more reliable analysis of GHG reduction potential.

• Journal of Korea Ship Safrty Technology Authority
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• s.27
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• pp.15-24
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• 2009

최근 IMO에서는 온실가스 배출을 규제화 하고자 하는 동향이 있으며 조만간 선박에서 온실가스 배출의 규제가 실현될 것으로 예상된다. 선박에서 배출되는 온실가스는 CO$_2$가 대부분을 차지하고 있으며 세계경제상황에 따른 영향이 고려되지만 지속적으로 증가추세에 있는 CO$_2$를 감소시키기 위한 아국의 대처방안이 필요한 시점이다. 또한 향후 발효될 EEDI를 소개하고 결과적으로 GHG를 저감시키기 위한 방안인 선형개선, 폐열회수시스템, 친환경연료사용기관, SEMP 등에 관한 내용을 다루어 보았다. 이 보고서에서는 GHG를 비롯한 NOx, SOx 및 PM과 같은 유해배출물질을 Top Down방식으로 평가함으로써 선박에서 기인하는 대기오염물질 관련 국내정책 및 해운산업의 장기적인 발전전략에 유용하게 사용될 것으로 기대한다.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.604-612
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• 2012

Self-management plan for GHG (Greenhouse Gas) reduction should be prepared in academic facilities, which occupy a large amount of energy consumption. In this study, a university was chosen as one of the major academic facilities and its energy consuming pattern and GHG emission were analyzed. The results have shown that annual $CO_2$ emission from university buildings was 10,452 ton-$CO_2$ (0.65 ton-$CO_2/m^2$), and dependent upon 78.0% electricity, 20.5% LNG and 1.5% oil, respectively as energy sources. According to more detail analysis by usage of energy consumption, appliances occupies 36.7% followed by gas heating (18.9%), lighting (18.6%), heating with electricity (12.5%), cooling with electricity (10.2%), transportation (1.5%), gas cooling (1.2%) and cooking (0.4%). Furthermore, annual $CO_2$ emissions per unit area and a student by electricity usage were evaluated to 51.30 kg-$CO_2/m^2$ and 981.86 kg-$CO_2$/capita, respectively and those by LNG usage were 14.61 kg-$CO_2/m^2$ and 241.01 kg-$CO_2$/capita.