• 한국진공학회지
• /
• 제8권4A호
• /
• pp.417-424
• /
• 1999

In order to investigate field emission mechanism of undoped polycrystalline diamond films, diamond films with different structural properties were deposited by varying positive substrate bias and/or $CH_4$ concentration. When increasing $CH_4$ concentration and positive substrate bias voltage, nondiamond carbon content in diamond films increased. Increase of nondiamond carbon content with increasing substrate voltage is ascribed to increase of substrate and excess generation of $CH_n$ radicals. Field emission properties of undoped polycrystalline diamond films ere significantly enhanced with increasing nondiamond carbon content. For diamond films with a small amount of nondiamond carbon, electrons are emitted through diamond surface while for the films with a large amount of nondiamond carbon, electron emission occurs through diamond bulk as well as surface. From this study, depending on nondiamond carbon content two field emission mechanisms were suggested.

• KIEAE Journal
• /
• 제10권5호
• /
• pp.123-129
• /
• 2010

This study aimed at analyzing the trend of carbon dioxide emission for direct and indirect areas by using inter industry relations table between 2000, 2003 and 2005 in the key building materials and components. Results of this study are as follows; First, the material and components for this study was selected in 20 industries of products such as sand, gravel, cement, concrete articles, rebar, and steel bar. Second, among the 20 selected key building materials, the group with the highest carbon-dioxide emission was shown in ready-mixed concrete, concrete articles, and primary aluminum goods. Third, as a result of analyzing the changes to the units of carbon dioxide emission according to passage of time, the number of items which is changed in such as sustained increase or decrease over time was insignificant in carbon-emission change trend.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 추계학술대회 논문집
• /
• pp.519-523
• /
• 2000

Using plasma-enhanced chemical vapor deposition (PECVD), carbon thin film as electron field emitter were fabricated. These carbon thin film were deposited on Si(100) substrate at several RF power. These film were estimated by raman spectroscopy, scanning electron microscopy, and field emission. The field electron emission property of these carbon thin film was estimated by a diode technique. As the result, we observed that the field emission properties of these films were promoted by higher RF power. These results are explained as change of surface morphology and structural properties of carbon thin film

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
• /
• pp.692-695
• /
• 2004

Fabrication of photosensitive carbon nanotubes paste and its post-treatment has been developed for high resolution with good electron emission uniformity. We report novel post-treatment techniques including rubber-rolling and multiple field emission cycling from which we could improve the field emission properties of printed carbon nanotubes. These techniques would be easily applicable to large area field emission display using paste of carbon nanotubes

• 한국결정성장학회지
• /
• 제14권5호
• /
• pp.211-214
• /
• 2004

Carbon nanofiber bundles were formed on silicon substrate using microwave plasma-enhanced chemical vapor deposition system. These bundles were vertically well-grown under the high negative bias voltage condition. The bundles were composed of the individual carbon nanofiber having less than 100 nm diameters. Turn-on voltage of the field emission was measured around 0.8 V/$\mu\textrm{m}$. Fowler-Nordheim plot of the measured values confirmed the field emission characteristic of the measured current.

• 환경영향평가
• /
• 제20권1호
• /
• pp.79-87
• /
• 2011

In this study, we investigated the effect of carbon sequestration and sink on the environmental impact assessment of a housing redevelopment project. Through the case study, we found that the amount of carbon sequestration and sink increased with the increase of the area of park and green space and, furthermore, the amount of carbon emission decreased slightly with implementation of district heating and renewable energy. Therefore, it is necessary for its land use plan to be established to minimize the amount of net carbon emission, taking account of both the amount of present carbon emission and the amount of the future carbon sink, sequestration, and emission.

• 대한공간정보학회지
• /
• 제19권4호
• /
• pp.81-89
• /
• 2011

저탄소 녹색성장은 국내외적으로 중요한 이슈가 되고 있으며, 중앙정부 및 각 지자체별로 기본계획 및 데이터베이스를 구축하고 다양한 관련 연구를 진행중이다. 이러한 관점에서 지자체의 탄소배출량 및 탄소흡수량을 계산한 탄소배출총량은 향후 도시계획 및 관리에 있어 중요한 요소가 될 수 있다. 본 연구에서는 경기도를 대상으로 통계자료 및 수치임상도를 이용하여 탄소발생총량을 산출하고 탄소발생환경을 분석해 보았으며, 그 결과 산림면적이 넓고 탄소흡수율이 우수한 품종을 많이 보유한 가평군, 양평군, 연천군, 과천시, 동두천시, 여주군 등의 탄소발생총량이 비교적 적은 것으로 분석되었다. 향후 주기적인 연차별 데이터베이스 구축을 위해서는 위성영상 등을 이용한 탄소흡수량 추정 등이 필요하며, 이러한 기반 자료들은 저탄소 녹색성장을 위한 정책기반자료로서 활용가능할 것이다.

• Spatial Information Research
• /
• 제19권3호
• /
• pp.11-22
• /
• 2011

이산화탄소의 배출량을 산정하는 방식은 주로 제련소, 화력발전소 등 제조공정에서 소비되는 에너지 통계에 의거하여 배출량을 추정하는 방식으로 이루어지고 있다. 본 연구는 지목이 토지이용패턴에 따라 다르게 배출되는 이산화탄소를 감시하기 위한 지표로 활용될 수 있는지를 평가하고자 수행되었다. 그리하여 사례 연구지역에서 이산화탄소 배출량을 측정하여 토지이용의 관점에서 지목별 변화 추세에 대한 평가가 이루어졌다. 정부통계에만 의존하는 간접추계 방식과 달리 지목 기반의 평가는 광역적인 이산화탄소 농도의 분포실태를 단시간에 제시하였다. 특히 대지 등 비자연적인 지목에서 높은 수치를 보여주었다. 반면, 임야 등 흡수원으로 특성을 지닌 지목은 전체적으로 배출원에 비해 낮은 수치를 보여주었다. 본 연구의 가장 큰 성과는 지목별 이산화탄소 배출량 변화 실태를 정량적으로 제시하고 있기 때문에 각종 개발사업의 계획단계부터 배출원과 흡수원을 지정하고 관리함에 있어 지목에 의거 도로 건설 등 저탄소 도시에 부정적인 영향을 미치는 개발사업을 규제하는 과정에서 온실가스 배출을 최소화하기 위한 지표로서 설득력을 지닌 근거자료로 지목의 가능성을 보여주었다. 본 연구의 가장 큰 성과는 "지목 기반의 이산화탄소 배출 감시"라는 새로운 개념을 제시하였다는 데 있을 것이다.

• The Journal of Asian Finance, Economics and Business
• /
• 제4권4호
• /
• pp.61-66
• /
• 2017

Environmental awareness and its relation to the development of economy has garnered increased attention in recent years. Researchers, over the years, have argued that sustainable development warrants for minimizing environmental degradation since one depends on the other. This study analyzes the relationship between environmental degradation (carbon emission taken as proxy for degradation), economic growth, total energy consumption and industrial production index growth in Bangladesh from year 1998 to 2013. This study uses Vector Autoregression (VAR) Model and variance decomposition of VAR to analyze the effect of these variables on carbon emission and vice-versa. The findings of VAR model suggest that industrial production and GDP per capita has significant relationship with carbon emission. Further analysis through variance decomposition shows carbon emission has consistent impact on industrial production over time, whereas, industrial production has high impact on emission in the short run which fades in the long run which is consistent with Environmental Kuznets Curve (EKC) hypothesis. Carbon emission rising along with GDP per capita and at the same time having low impact in the long run on industrial index indicates there may be other sources of pollution introduced with the rise in income of the economy over time.

• 한국조경학회지
• /
• 제23권3호
• /
• pp.80-93
• /
• 1995

The purpose of this study was to assess functioni fo urban greenspace to reduce atmospheric CO\sub 2\ concentration. The study quantified carbon storage in urban greenspace and carbon emission by fossil fuel consumptio in Chuncheon. The amount of carbon storage in vegetation by land use type was 0.02kg/$m^2$ for commercial land, 4.36kg/$m^2$ for natural land, and 0.54kg/$m^2$ for the other urban lands. In 1994, total amount of carbon emission by fossil fuel consumption was about 257,358 metric tons, and the per capita carbon emission was 1.4 metric ton. Total amount of carbon storage in vegetation was 42,942 metric tons, approximately 17% of the carbon emission. This study excluded quantification of carbon storage in soils. The role of urban greenspace to sequester atomspheric carbon might be much greater, if a soil greenspace to sequester atmospheric carbon might be much greater, if a soil greenspace to sequester atmospheric carbon might be much greater, if a soil carbon storage is included quantification of carbon storage is included. However, increasing coverage of trees and managing them for healthy growth would not be sufficient for avoiding adverse impacts by future climate change. Additional measures should be followed such as an increase of energy use efficiency and development of substitute energy.