• Proceedings of the KSME Conference
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• 2008.11b
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• pp.3026-3031
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• 2008

In conventional closed-loop crankcase ventilation systems, the lubrication oil had to be re-circulated to the intake manifold, in the form of oil mist mixed with the blow-by gas. This blow-by gas containing the engine lubricant oil affects on the engine problems and the exhaust emissions. A high-efficient oil separator is required to minimize consumption of engine oil and reduce harmful emissions. In the conventional oil separator of CI engines, it has good oil separation performance even though separator design is simple, due to lots of the blow-by gas. As the emission regulation becomes severe, the oil separator for SI engines is also required. But in SI engines, separator design should be optimized, due to small size of oil particles and little amount of blow-by gas. In this study, oil separation performance classified by diameter of oil mist in cylinder head cover internal model which has three cyclones and two baffle plates for SI engine is calculated with CFD methodology.

• Journal of Conservation Science
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• v.30 no.2
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• pp.235-241
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• 2014

In this study, we are trying to verify humidity control capability of the exhibition environment of cultural property by measuring adsorption and desorption performance, the control ability of harmful substances by the adsorption experiments of harmful gases. In the experiment of adsorption and desorption performance, in the low humidity area, Artsorb desorbed overwhelmingly more than activated carbon whereas activated carbon absorbed more. Adsorption speed was faster slightly in Artsorb absorption speed was similar in both. In the middle humidity area, absorption by artsorb was slightly more and desorption was similar in both so characteristic of Artsorb didn't appear. Also, Adsorption speed was faster in activated carbon but in the process of desorption, the speed of Artsorb was faster. In adsorption experiment of harmful substances, the concentration in the environment with activated carbon was lower than one with Artsorb, but the difference appeared small. And as a result of observation of the difference in concentration due to adsorption of harmful gas by the change in the metal specimen, the most change was shown in lead specimen and the color difference between the lead specimens of the activated carbon and Artsorb appeared greatly.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.431-438
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• 2016

Recently, Both rapid economic growth and high-quality native finishing materials demand in buildings such as local infrastructure facilities and cultural facilities have increased along with local quarries. So, increasing local quarries and environmental pollution occurred in quarries get the eyes to damaged area of the surroundings. As an example, carcinogen such as solid formed to fixing asbestos and dust have damaged to local resident. Especially, Radon gas released from asbestos can exist everywhere on earth, released soil and rock as radioactive substances, can be caused lung cancer followed by a smoking. When pollution source to indoor air quality that lacking ventilation rate of the residential building moved in a cycle, human responses such as headache, dizziness, etc. get appear, so on it threatened resident's physical condition. Thus, we need to urgent attention to reduction harmful substance. In the case of radon gas of the pollution source to indoor air quality in housing, it has characteristic that keep on going through half-life released from source, we need to control radon gas source than source removal. We set on vermiculite addition ratio to 10% which has harmful substances adsorption performance, proceed experiment to basalt waste rock addition ratio 50, 60, 70, 80(%). The result of an experiment, based on 'KS F 4035, precast terrazzo', we can be obtainable in the best terrazzo at basalt waste rock addition ratio 70%.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.5
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• pp.249-254
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• 2016

In this study, we investigated the main characteristics of off-gas generated from melting process and off-gas treatment system operation example to provide some primary data for commercial vitrification facility design. The purpose of vitrification facility operation is to treat hazardous materials in the radioactive wastes and harmful off-gas containing a variety of chemical species generated in the glass melting process. Constructing and operating vitrification facility essentially need to be licensed through safety analysis; it is very important to treat radionuclide and hazardous materials below the legal environment emissions regulation level. We must accurately understand the characteristics of off-gas and apply an appropriate off-gas treatment process accordingly. Thus, to design the appropriate off-gas treatment there must be a wide range of elements taken into account such as characteristics of waste and melter, regulation guidance of off-gas, characteristics of generated off-gas and off-gas treatment system performance assessment.

• Special Issue of the Society of Naval Architects of Korea
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• 2013.12a
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• pp.30-34
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• 2013

Prevention of exhaust gas back flow becomes a great interest to shipyards and shipowners in large container carriers because exhaust gas pollutes cargoes, flows back into the deck house and the engine room area through fresh air intakes and fan rooms, gives harmful damages to the crew's health and also gives thermal damages to electric equipments on the navigation deck. The phenomena of exhaust gas back flow has been studied with the analysis of sea trial records and wind tunnel tests and the height of the exhaust gas pipe, the front area of the deck house, the inflow speed and the position of the radar mast platform has been confirmed as the principal factors of exhaust gas back flow phenomena. The simple empirical formula to estimate exhaust gas back flow phenomena and the design guidances of exhaust gas related structures on deck has been introduced. In future, parametric studies for the exhaust gas back flow factors will be carried out with the CFD analysis. The results of this study will be the guide for development of the prevention method of exhaust gas back flow phenomena for large container carriers.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.1
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• pp.14-21
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• 2008

Synthetic gas is defined as reformed gas from hydrocarbon-based fuel and the major chemical species of the synthetic gas are $H_2$, CO and $N_2$. Among them, hydrogen from synthetic gas is very useful species in chemical process such as combustion. It is a main reason that many studies have been performed to develop an effective reforming device. Furthermore, other technologies have been studied for synthetic gas application, such as the ESGI(Exhaust Synthetic Gas Injection) technology. ESGI injects and burns synthetic gas in the exhaust pipe so that heat from hydrogen combustion helps fast warmup of the close-coupled catalyst and reduction of harmful emissions. However, it is very hard to understand combustion characteristic of hydrogen under low oxygen environment and complicated variation in chemical species in exhaust gas. This study focuses on the characteristics of hydrogen combustion under ESGI operating conditions using a CVC(Constant Volume Chamber). Measurements of pressure variation and flame speed have been performed for various oxygen and hydrogen concentrations. Results have been analyzed to understand ignition and combustion characteristics of hydrogen under lower oxygen conditions. The CVC experiments showed that under lower oxygen concentration, amount of active chemicals in the combustion chamber was a crucial factor to influence hydrogen combustion as well as hydrogen/oxygen ratio. It is also found that increase in volume fraction of oxygen is effective for the fast and stable burning of hydrogen by virtue of increase in flame speed.

• Journal of Power System Engineering
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• v.19 no.6
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• pp.47-53
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• 2015

Korea is the geographic location during the summer, the temperature rising to $35^{\circ}C$ and winter temperature is $-15^{\circ}C$ to reduce the air temperature changes, such as relatively large compared to other countries. This increase or decrease of the harmful exhaust gas discharged from automobile substantially inconvenience a significant impact on the active side of the car engine temperature and exhaust gas reducing device receives a large impact on the atmospheric temperature is regulation to be different. However, domestic vehicle emissions test temperature of $20{\sim}30^{\circ}C$ is it does not reflect this situation the actual test temperature to accurately measure the exhaust gas volume of the vehicle is difficult. In this study, domestic automobile exhaust gas test conditions of a test temperature $20{\sim}30^{\circ}C$ various temperatures, including (35, 25, 0, -7, -15, $-25^{\circ}C$) under the two vehicles (2.0L MPI, 2.4 L GDI) as was discussed with respect to the exhaust gas characteristics of the vehicle according to the ambient temperature gas. As a result, domestic emissions test temperature of $25^{\circ}C$ than average conditions were temperature decreases greenhouse gas emissions and increase overall increased by up to 15 times higher. Air temperature and the engine exhaust gas inconvenience a direct effect on the activation temperature required in the reduction unit is determined to be an increase of emissions and greenhouse gases, and also an increase in the variety of lubricants based lubricating and viscosity reduction, such as the engine oil due to the low temperature of these result It is considered that shows the.

• Proceedings of the Korea Contents Association Conference
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• 2010.05a
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• pp.396-398
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• 2010

밀폐된 공간으로 이루어진 작업장은 여러 가지 유해가스가 많이 발생된다. 이로 인해 환기가 불충분한 작업공간에서는 산소결핍 및 유해가스로 인한 건강장해와 인화성 물질에 의한 화재, 폭발 등의 위험이 존재한다. 따라서 유해가스 정보를 작업장 내의 센서를 통해서 실시간으로 모니터링하고, 위험으로부터 작업자의 안전을 보장할 수 있는 모니터링 시스템이 필요하다. 특히, 상황에 맞는 의사결정이 가능하도록 하기 위해 상황인식 시스템의 도입이 필요하다. 이 논문에서는 작업장의 유해가스 정보를 모니터링하기 위한 추론 규칙을 JESS를 기반으로 설계한다.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.3
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• pp.211-222
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• 2014

Pork belly meat is one of the most preferred food items for many Korean people. The odorants released from cooking of pork belly meat were measured by three kinds of cooking methods (Charcoal-grill (C), Electric Pan (E), and Gas burner-pan (G)). A total of 16 target compounds including carbonyl compounds, volatile organic compounds, and poly aromatic hydrocarbon were selected and analyzed for comparative purposes. Their emission concentrations were quantified using HPLC-UV, GC-MS, GC-TOF-MS, etc. The gas samples collected by Charcoal-grill cooking showed generally enhanced concentrations of most target compounds among all three kinds of cooking methods. In Charcoal-grill, concentration of benzene, formaldehyde and pyrene went up to 543, 516, and 402 ppb, respectively. It the results are compared in terms of the sum of odor intensity, the highest value (4.25) was also seen from Charcoal-grill. The results of this study confirm that the significantly reduced emission of harmful pollutants can be attained, it pork belly meat is cooked by the Gas or electric pan instead of Charcoal-grill.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.335-346
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• 2015

The objective of this study was to evaluate the effect of dietary rosemary on performance, microflora population in cecum and noxious gas emission from litter of broiler. A total of 216 broiler chicks at 7 days old were fed the commercial diet (control), added 0.5% level of dried rosemary leaves (5 g/kg diet, T1) and 1.0% level of dried rosemary leaves (10 g/kg diet, T2) for 4 weeks. The body weight gain and feed conversion ratio were improved by feeding rosemary at 7 to 35 days of age (P<0.05), but there was no difference between T1 and T2. Amount of feed intake and mortality were not different among the three group. There was an increase in the microflora population of Lactobacillus (P<0.05) and decreased in E. coli and salmonella (P<0.05) in the cecum contents at 21 and 35 days of age. Emission of ammonia gas from litter was significantly decreased by supplementary rosemary at 21 to 35 days of age (P<0.05), but there was no difference between T1 and T2. These results indicated that feeding 0.5 to 1.0% level of dried rosemary leaves during broiler production improved in the body weight gain and feed conversion ratio because of increasing nutrient digestibility from feed, also increase in intestinal beneficial bacteria and decrease in harmful bacteria in the cecum contents, and decreasing emission of ammonia gas from litter.