• Journal of Korean Society for Atmospheric Environment
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• v.23 no.4
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• pp.498-506
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• 2007

To reduce the vehicular emissions of air pollutants, various traffic control programs (TCPs) have been used. In 2002, two TCPs have been implemented in Seoul and Busan, respectively. In this study, based on the study results on the effectiveness of the TCP in Seoul (Kim et al., 2005) and Busan (Lee et al., 2006), emission reduction by the TCP in Seoul was estimated and their contribution to the ambient air pollutants' concentrations was discussed. During the TCP period in 2002 at Seoul, emissions of air pollutants were reduced by 35% for CO and $NO_2$, 80% for HC, 23% for $PM_{10}$, and 24% for $SO_2$. Vehicular emission reduction affected the ambient concentrations significantly for $NO_2$. However, for $SO_2$, vehicular emission reduction did not affect the ambient concentration significantly. For $PM_{10}$, vehicular emission reduction did not affect the ambient concentration significantly if considering fugitive emissions.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.4
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• pp.313-320
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• 1998

The most desirable diesel oxidation catalyst (DOC) should have the properties of oxidibing CO and HC effectively at low exhaust gas temperature while minimizing the formation of sulfate at high exhaust gas temperature. Precious metals such as platinum and palladium have been known to be sufficiently active for oxidizing CO and HC and also to have high activity for the oxidation of sulfur dioxide (SO2) to sulfor trioxide (SO3). There is a need to develop a highly selective catalyst which can promote the oxidation of CO and HC efficiently, but, on the other hand, suppress the oxidation of SO2. One approach to solve this problem is to load a base metal such as vanadium in Pt-based catalyst to suppress sulfate formation. In this study, a Pt-V catalyst was prepared by impregnating platinum and vanadium onto a Ti-Si wash coated catalyst in a laboratory reactor by changing the formulations and reaction temperatures.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.3
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• pp.154-159
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• 2016

Recently it has been focused that the automobile engine has developed in a strong upward tendency for the use of the high viscosity and poorer quality fuels in achieving the high performance, fuel economy, and emission reduction. Therefore it is not easy to solve the problems between low specific fuel consumption, and exhaust emission control at automotive engine In this study, it is designed and used the test bed which is installed with fuel injector controller. In addition to equipped engine using CRDI by controlling the injection timing with modulator, it has tested and analyzed the engine cycle variation characteristics, as it is varied that they are the operating parameters: fuel injected quantity, injection timing, engine speed and scavenging pressure.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.463-476
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• 2017

Climate change is considered as the greatest threat to our future and descendants. The Korean government has set a target for 2030 to reduce emission of greenhouse gases (GHGs) by 37% from the business-as-usual levels which are projected to reach 851 million metric tons of $CO_2eq$ (Carbon dioxide equivalent). In Korea, GHGs emission from agriculture account for almost 3.1% of the total of anthropogenic GHGs. The GHGs emitted from agricultural land are largely classified into three types: carbon dioxide ($CO_2$), methane ($CH_4$), and nitrous oxide ($N_2O$). In Korea, rice paddies are one of the largest agricultural $CH_4$ sources. In order to analyze domestic research trends related to $CH_4$ emission from rice paddies, 93 academic publications including peer reviewed journals, books, working papers, reports, etc., published from 1995 to September 2017, were critically reviewed. The results were classified according to the research purposes. $CH_4$ characteristics and assessment were found to account for approximately 65.9% of the research trends, development of $CH_4$ emission factors for 9.5%, $CH_4$ emission reduction technology for 14.8%, and $CH_4$ emission modeling for 6.3%, etc. A number of research related to $CH_4$ emission characteristics and assessment have been studied in recent years, whereas further study on $CH_4$ emission factors are required to determine an accurate country-specific GHG emission from rice paddies. Future research should be directed toward both studies for reducing the release of $CH_4$ from rice paddies to the atmosphere and the understanding of the major controlling factors affecting $CH_4$ emission.

• Journal of the Korean Society of Visualization
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• v.14 no.1
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• pp.27-32
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• 2016

The reduction of $CO_2$ emissions has been a key target in the Marine Industry since the IMO's Marine Environment Protection Committee published its findings in 2009. The representative emission index is termed as the EEDI (Energy Efficiency Design Index) for the new ships. Among various flow control techniques ever proposed, the air lubrication method is the one of most promising one in terms of practical applicability. The present study examines the basic characteristics of the flat plate test with intention of applying the air lubrication technology to the reduction of the resistance of a ship. Image analysis technique is proposed as a tool to quantify the effectiveness of the air lubrication method.

• Architectural research
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• v.15 no.3
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• pp.143-150
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• 2013

The Korean government recently has rediscovered the potential value of Han-Ok, the Korean traditional house, as an eco-friendly building. In order to objectively verify the environmental performance of Han-Ok as a low carbon green building, this paper suggests the analysis method of GHG emission load of Korean traditional house, based on Life Cycle Assessment, which is commonly abbreviated to "LCA". The environmental impacts caused by building construction and operation can be analyzed through the sum of input and output data from every phase. The study particularly describes the GHG reduction effect by using traditional building materials such as wood products, traditional clay roof tiles, and mud, which are mainly used to construct Han-Ok. Also the study proposes the method for comparative analysis of quantity of GHG emissions in building's entire life cycle so that the data can be used as a reliable basis to optimize the environmental performance of building.

• Journal of the Semiconductor & Display Technology
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• v.12 no.2
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• pp.45-50
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• 2013

This paper focuses on the fundamental issues for improving the efficiency and throughput of the AC PDP (Plasma Display Panel) manufacturing. The properties of the MgO protective layer affect the PDP efficiency. Especially, the secondary electron emission efficiency was affected on the deposition rate of MgO during the evaporation. In this study, the deposition rate of 5 $\AA$/s has given the maximum efficiency value of 0.05 It is demonstrated that the impurity gases such as $H_2O$, $CO_2$, CO or $N_2$, and $O_2$ can be remained inside the PDP panel before sealing and the amount of the impurity gases decreased rapidly as the base vacuum level increased, especially near $10^{-5}$ torr. The fundamental solution in order to overcome these problems is the vacuum in-line sealing process from the MgO evaporation to the final sealing of the panel without breaking the vacuum. We have demonstrated this fundamental process technology and shown the feasibility. The firing voltage was reduced down to 285 V at the base vacuum value of $10^{-6}$ torr, whreras it was about 328 V at the base vacuum value of $10^{-3}$ torr.

• Journal of the Korean Institute of Gas
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• v.14 no.4
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• pp.51-55
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• 2010

The global activities to reduce the $CO_2$ emission as a greenhouse gas have been various efforts. Under this circumstance, small and medium sized gas field containing $CO_2$ to develop as LNG is not economic feasibility. Particularly, for the separation of $CO_2$ in gas field, separation facilities should be installed to add. This is and increase in plant construction cost and separated $CO_2$ emission into the atmosphere is not the result of greenhouse gas reduction. When the uneconomic gas field apply the KOGAS DME process, the gas field containing $CO_2$ can be increase economic feasibility because of natural gas and $CO_2$ can be use to resource gas. The Tri-reformer produced syngas as H2 and CO in KOGAS DME process and the resource gases are natural gas, steam, oxygen and $CO_2$. The $CO_2$ is used as raw material gases from recover $CO_2$ in DME process. In this study, we investigated range of application of $CO_2$ in gas field.

• Atmosphere
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• v.31 no.5
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• pp.593-606
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• 2021

The Korea Meteorological Administration/National Institute of Meteorological Sciences (KMA/NIMS) has monitored atmospheric CO₂ at Anmyeondo (AMY) World Meteorological Organization (WMO) Global Atmosphere Watch Programme (GAW) regional station since 1999, and expanded its observations at Jeju Gosan Suwolbong station (JGS) in the South and at Ulleungdo-Dokdo stations in the East (ULD and DOK) since 2012. Due to a recent WMO CO₂ scale update and a new filter (NIMS) to select baseline levels at each station, the 22 years of CO₂ data are recalculated. After correction for the new CO₂ scale, we confirmed that those corrected records are reasonable within the compatibility goal (±0.1 ppm of CO₂) between KMA/NIMS and National Oceanic and Atmosphereic Administration (NOAA) flask-air measurements with the new scale. With the new NIMS filter, CO₂ baseline levels are now more representative of the large-scale background compared to previous values, which contained large CO₂ enhancements. Atmospheric CO₂ observed in South Korea is 4 to 8 ppm greater than the global average while the amplitude of seasonal variation is similar (10~13 ppm) to the amplitude averaged over a comparable latitude zone (30°N-60°N). Variations in CO₂ growth rate are also similar, increasing and decreasing similar to global values, as it reflects the net balance between terrestrial respiration and photosynthesis. In 2020, atmospheric CO₂ continued increasing despite the COVID-19 pandemic. Even though fossil emission was reduced (around -7% globally), we still emitted large amounts of anthropogenic CO₂. Overall, since CO₂ has large natural variations and its source was derived from not only fossil fuel but also biomass burning, the small fossil emission reduction could not affect the atmospheric level directly.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.4
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• pp.357-364
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• 2016

Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the combustion stability and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.