• Journal of Advanced Marine Engineering and Technology
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• v.24 no.4
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• pp.441-445
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• 2000

Considering international status of our country as world class ship builder and geographical characteristics encircled by sea in three facets, controlling of air pollutants emission from marine engines becomes more and more important issue in recent days. Implementation of immediate pollutants emission control regulation and standardization of test and certification procedure are required to reduce air pollution from marine engines. But cost increments due to additional equipment of emission control device and development and certification test expenses as well as depreciation of fuel economy should be considered. To satisfy those air pollution reduction and economic requirements, we should make our own interpretation of IMO standard and implementation schedule depending on our country's status. For this purpose we measured NOx emission from small and middle class marine engines to calculate emission factor and total pollutant emission in our country. With the comparison and analysis of other countries emission control regulation we proposed basic data of total emission from marine engine and future emission control standard in our country. According to our estimation, 62% of total NOx emission of marine engines comes from fishing boat and 38% from commercial vessels. The portion of NOx emission from marine engine is 18.6% of whole country NOx emission. Due to the voyage characteristics of middle and large vessel and necessity of international harmonization of marine engine pollutants emission control standard, it is inevitable to adopt IMO standard for middle and large marine engines. But considering technological and cost effect of fishing boat operating in near sea, it is resonable to set a standard within 80% of measured value at the moment and gradually implement the same IMO standard in near future.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.2
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• pp.153-162
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• 1995

As exhaust emission standards for new passenger cars amended in 1987 have become more stringent, vehicle manufacturers have employed three-way catalyst in order to meet these requirements. The purpose of this study was to gather informations on new emission control systems in customer use for in-use vehicles from the 1987 through 1992 model years were capable of achieving low exhaust emission levels although high levels do occur due to defects, deterioration or maladjustments with the emission control equipment. The vehicles with closed loop electronic control fuel injection system emitted low exhaust emission, but the carburetor control system equipped vehicles emitted high exhaust emissions and the high mileage vehicles exhibited higher average emissions than low mileage vehicles. It was also found that the useful life of 80, 000km is very important to maintain the low emission levels within customer service period.

• Journal of the korean Society of Automotive Engineers
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• v.11 no.5
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• pp.1-12
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• 1989

This short report describes the trend of exhaust emission control of the diesel engine vehicles in Korea, which originally was motivated from the newly proposed Emission Control Regulation of Diesel Engine Vehicles possible to be activated in 1991 by Korean Environmental Protection Agency. This short survey report has been prepared by the special working group of The Korea Society of Automotive Engineers (KSAE) on this particular subject. This report includes (1) estimation of portions of contribution of diesel engine vehicle emission to total air pollution, (2) comparison of proposals of new articles/regulations/laws in Korea with those of other selected countries such as USA, European countries, and Japan, (3) comparison of vehical emission control regulations in Korea with those in other selected countries, (4) technical aspects of possibilities of reduction of diesel engine vehicle emissions, (5) additional administrational aspects of technology development program, (6) social impact resulted from the severe emission control regulation on diesel engine vehicles, and (7) proposals, prepared by the special working group of the KSAE, on the emission control regulation of diesel engine vehicles, which can possibly bring better cleaner air released from the air pollution resulted from diesel engine exhaust emissions in real sense with minimal financial contribution, with optimal technological efforts, with less social impacts, within five to ten year period.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.10
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• pp.37-44
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• 2018

In this study, the effects of considering hourly metabolic rate variations for predicted mean vote (PMV) control on the heating and cooling energy and greenhouse gas emission were investigated. The case adopting PMV control taking the hourly metabolic rate into account was comparatively analyzed against the conventional dry-bulb air temperature control, using a detailed simulation technique. Under the assumption that all the apartments in Korea adopt the PMV control incorporating real-time metabolic rate measurements, nationwide reductions of primary energy and greenhouse gas emission were analyzed. As a result, PMV control considering hourly metabolic rate variations is expected to reduce national primary energy by 6.2% compared to conventional dry-bulb air temperature control, corresponding to reduction of 10,342 GWh. In addition, it turned out that 6.6% of tCO2 emission can be reduced by adopting PMV control, corresponding to nationwide reduction of greenhouse gas emission by approximately 1,720,000 tCO2.

• Journal of Multimedia Information System
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• v.2 no.4
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• pp.317-326
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• 2015

The paper deals with the analysis of the effectiveness of acoustic emission monitoring and diagnostics of engineering products. We discuss the results of the processing results of the field experiment to study the acoustic emission in the alloy and its welded joints in the presence of technological defects. We study the characteristics of the output of acoustic emission signals at different stages of elastic-plastic deformation of alloys. Analyzed acoustic chart and the output waveform of the acoustic emission for the different types of welds. Studies have shown the effectiveness of the Acoustic emission techniques and help improve the accuracy of non-destructive testing systems in problems of automation and control.

• Geomechanics and Engineering
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• v.10 no.3
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• pp.297-314
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• 2016

With the mining depth continuously increasing, gas emission behaviors become more and more complex. Gas emission is an important basis for choosing the method of gas drainage, gas controlling. Thus, the accurate prediction of gas emission is of great significance for coal mine. In this work, based on the sources of gas emission from the heading faces and the fluid-solid coupling process, we established a gas continuous dynamic emission model, numerically simulated and applied it to the engineering. The result was roughly consistent with the actual situation and shows the model is correct. We proposed the measures of reducing the excavation distance and borehole gas drainage based on the model. The measures were applied and the result shows the overproof problem of gas emission disappears. The model considered the influence factors of gas emission wholly, and has a wide applicability, promotional value. The research is of great significance for the controlling of gas disaster, gas drainage and pre-warning coal and gas outbursts based on gas emission anomaly at the heading face.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.5
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• pp.410-419
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• 2009

Generally, air pollutant emission at workplace is estimated by two methods: indirect methods using emission factors and direct methods based on CEMS (Continuous Emission Monitoring System). CAPSS (Clean Air Policy Support System) is a representative indirect method and the national air pollutant database of Korea. However, characteristics of some workplaces may create a gap between CAPSS and CEMS data. For improving of emission data accuracy, emission data of CEMS (named CleanSYS) equipped at 138 target workplaces were compared with those of CAPSS. As a result, $SO_x$ and $PM_{10}$ emission levels obtained by CAPSS were lower than those of CleanSYS. $SO_x$ and $PM_{10}$emission ratios were 61.5% and 71.2% lower respectively, showing the biggest gaps. On the other hand, $NO_x$ emission of CAPSS was higher by 10.4%. $SO_x$ showed the biggest difference in 'Energy industry combustion' and $NO_x$ did in 'Production Process' within the SCC category. $PM_{10}$ presented a large gap in 'Manufacturing industry combustion.' The differences in $SO_x$ between the two systems occurred because some large-size facilities lack pollution controllers or efficient pollution controllers. Based on this study, CAPSS emission database of Korea will improve accuracy through adopting CEMS emission system, which enables more efficient national atmospheric policies and workplace management.

• Journal of the Semiconductor & Display Technology
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• v.9 no.4
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• pp.7-12
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• 2010

Field-emission characteristics of carbon nanotubes(CNTs), which were grown on conical-type tungsten micro-tips by using an electrophoretic deposition(EPD) method, were examined. The EPD method proved to be convenient to manipulate and arrange CNTs from well dispersed suspensions onto such tip-type substrates. The growth rate of CNTs was proportional to the applied d.c. bias voltage and the process time. It was observed from the Raman study that the EPDproduced CNTs showed better crystal qualities with the Raman intensity ratio( $I_D$/$I_G$) of 0.41-0.42 than the CVD-produced CNTs and their crystal qualities could be further improved by thermal annealing. The electron emitters based on the EPDCNTs showed excellent field emission properties, such as the threshold voltage for electron emission of about 620 V and the maximum emission current of about 345 ${\mu}A$. In addition, the EPD-CNTs exhibited the stable long-term(up to 40 h) emission capability and the emission stability was enhanced by thermal annealing.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.5
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• pp.507-516
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• 2010

Stationary combustion sources such as coal-fired power plants, waste incinerators, industrial manufacturing, etc. are recognized as major sources of mercury emissions. Due to rapid economic growth, zinc production in Korea has increased significantly during the last 30 years. Total zinc production in Korea exceeded 739,000 tons in 2008, and Korea is currently the third largest zinc producing country in the world. Previous studies have revealed that zinc smelting has become one of the largest single sectors of total mercury emissions in the World. However, studies on this sector are very limited, and a large gap in the knowledge regarding emissions from this sector needs to be bridged. In this paper, Hg emission measurements were performed to develop emission factors from zinc smelting process. Stack sampling and analysis were carried out utilizing the Ontario Hydro method and US EPA method 101A. Preliminary data showed that $Hg^0$ concentrations in the flue gas ranged from 4.56 to $9.90\;{\mu}g/m^3$ with an average of $6.40\;{\mu}g/m^3$, Hg(p) concentrations ranged from 0.03 to $0.09\;{\mu}g/m^3$ with an average of $0.04\;{\mu}g/m^3$, and RGM concentrations ranged from 0.23 to $1.17\;{\mu}g/m^3$ with an average of $6.40\;{\mu}g/m^3$. To date, emission factors of 7.5~8.0 g/ton for Europe, North America and Australia, and of 20 or 25 g/ton for Africa, Asia and South America are widely accepted by researchers. In this study, Hg emission factors were estimated using the data measured at the commercial facilities as emissions per ton of zinc product. Emission factors for mercury from zinc smelting pross ranged from 4.32 to 12.96 mg/ton with an average of 8.31 mg/ton. The emission factors that we obtained in this study are relatively low, considering Hg contents in the zinc ores and control technology in use. However, as these values are estimated by limited data of single measurement of each, the emission factor and total emission amount must be updated in future.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.485-493
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• 2011

In Korea, PM (Particulate Matter) emissions caused by coal-fired power plants are measured by a system, so called Clean Air Policy Support System (CAPSS), which uses foreign emission factors. However, the system fails to reflect the characteristics of domestic power plants. In this regard, this study aims to develop local, accurate domestic emission factors. The study measured the amount of TSP (Total Suspended Particulates), PM10 and PM2.5 by collecting samples from the latter parts of pollution control devices which were installed at 3 bituminous-fired power plants and 3 anthracite-fired power plants. The results showed that the average concentrations of TSP, PM10 and PM2.5 measured at bituminous-fired power plants were 4.63 mg/$Sm^3$, 2.96 mg/$Sm^3$ and 3.07 mg/$Sm^3$ respectively, much higher than those from anthracite-fired power plants (2.96 mg/$Sm^3$, 2.47 mg/$Sm^3$ and 1.37 mg/$Sm^3$, respectively). In addition, bituminous-fired power plants showed higher ratios of PM10/TSP and PM2.5/TSP with 0.66 and 0.92, respectively, compared to 0.82 and 0.46, the ratios of PM10/TSP and PM2.5/TSP measured in anthracite-fired power plants. Emission factors based-on concentration measurements were also higher for bituminous-fired power plants, and PM with smaller particles tended to have bigger difference in emission factors between the two fuels. This study calculated the amount of PM emissions by using the estimated emission factors. When it comes to the PM emissions, it was less than that of CAPSS while similar to that of CleanSYS in its amount. It is expected that the emission factors developed by this study will be used in Korea replacing foreign emission factors currently used in Korea by ensuring the objectivity and reliability as domestic emission factors.