• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.1
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• pp.39-43
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• 2015

The Energy and Green House Gas target management system was launched by the Korean Government in 2010. The Korea Emission Trading System will start in 2015. Therefore, simultaneous pursuit of energy saving and greenhouse emission reduction through energy use rationalization is an important obligation of Korean engineers, who import about 97% of domestic energy consumption. Economic analysis of the GHG emission reduction methodologies registered and approved by Korea Voluntary Emission Reduction (KVER) program was conducted. The results for waste heat recovery employed in an energy intensive pulp, paper and wood industry were reported. The emission reduction intensities were 9.7 kg $CO_2$/ton_pulp production. Net Present Value analysis showed that the GHG emission reduction was economically beneficial with an internal rate return of 60%. The results of exergy analysis indicated that the second law efficiencies of waste heat recovery system employed in KVER program were 77.3% and 53.6%. NPV decreased as the exergy decreased.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.7-13
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• 2003

This study was carried out to optimize premixed burner and heat exchanger of the condensing gas boiler which can save energy by utilizing latent heat of combustion gas and reduce pollutant in exhaust gas. The heat exchanger of the gas boiler was composed of three parts, which were an upper, lower, and coil heat exchanger. The upper heat exchanger was placed outside of the premixed burner and a lower heat exchanger was located under the upper heat exchanger. And, coil heat exchanger rounded the outer surface of an upper and lower heat exchanger. The boiler designed by this research reaches turn-down ratio 4:1 in the domain of equivalence ratio 0.75${\~}$0.8 and thermal efficiency of $97\%$. Emission of NOx and CO concentration was under 20ppm and 140ppm at equivalence ratio 0.8. When diameter of the burner is replaced from 60mm to 50mm, emission of CO was reduced about 50ppm remarkably.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.8
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• pp.675-678
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• 2001

We fabricated the organic light emittign diodes (OLEDs) with ITO/Cu-Pc/triphenyl-diamine (TPD)/TPD+tris-(8-hydroxyquinoline) aluminum (Alq$_3$)/Al. The electrical properties of Cu-Pc thin film were studied as a hole injection layer. the energy gap of Cu-Pc thin films is decreased according to the substrate heat treatment temperature increased. It could be controlled the hole mobility by changing the heat treatment condition of Cu-Pc. The emission wavelengths could be controlled by changing hole mobility and recombination zone in emission layer.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.6
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• pp.608-614
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• 2015

Nitrogen oxide(NOx) emission reductions are required to meet the strict emission regulations for environmental protection. Most of the Exhaust Gas Recirculation(EGR) system applied to a diesel engine can relatively decrease the NOx at a low cost, but it has a disadvantage in that the PM generation is promoted due to the hot intake air temperature. Thus, high heat exchange efficiency of the EGR cooler is required for an effective removal of NOx. In this study, heat exchange efficiency for various types of heat exchangers used in EGR cooler was measured under same conditions, and determined best heat exchange performance shape depending on type of heat exchanger.

• Journal of Power System Engineering
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• v.20 no.5
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• pp.37-45
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• 2016

Exhaust gas recirculation has the advantage of being low-cost and easy to control of NOx emission. Therefore, it is most generally used to reduce NOx emission according to strengthen regulation. In the case of a non-road engine, such as the agricultural engine, since it mainly operate a middle or high-load state, NOx emission is decreased in accordance with the mapping range of the EGR rate, but results in an increase in the particulate matter which is caused to deposit and fouling problem of the EGR system. This problem has become an important issue for maintaining the performance of the engine, as well as emission performance. This study had examined the effects of cooler aging on the performance of heat transfer efficiency and NOx emission in non-road diesel engine. As a result of the EGR cooler aging during 200 hours engine operation, the cooling performance decreased about 25% compared with that of fresh cooler and the NOx emission increased about 14.6% on NRSC(non-road steady cycle) and 20% on NRTC(non-road transient cycle) compared with that of fresh cooler respectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.5-6
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• 2011

CO₂ reduction is the most urgent issue the world is facing. So, there should be a measure to reduce the CO₂ emission in construction industry which has more released CO₂ gas than other industries. CO₂ emission of building depend on using energy. Then efficient energy use process working efficiently at CO₂ reduction. Therefore In this study, author find the technical possibility of saving the building energy using the PCM which is able to control heat, storage heat and potential heat. So, it considered that apply to floor heating type which is major heating system of living space in Korea. And evaluate the Using possibility.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.201-204
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• 2015

Recently, energy excessive consumption and environmental pollution are the social issued. The most efficient way to solve both energy excessive consumption and environmental pollution is existing combustion system improved. This study was part of the assume and commercial used existing waste heat recovery condensing boiler to low emission performance for exhaust gas recirculation(EGR) and thermal efficiency rise by applying the condensed water recirculation(CWR) conducted. The researchers applied the EGR and CWR develop a new concept for the condensed water recirculation waste heat recovery condensing boiler. Waste heat recovery condensing boiler applied to the condensed water recirculation thermal efficiency of the same conditions was increased by about 4.8~5.5% and pollution emission also decreased.

• Journal of ILASS-Korea
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• v.20 no.4
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• pp.254-260
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• 2015

The objective of this study is to investigate the effect of multi-hole nozzle on the performance of small CRDI engine. Combustion and exhaust emission characteristics of engine were studied by using CFD simulation with ECFM-3Z combustion model. The conditions of simulation were varied with nozzle geometry, injection timing and injection quantity. In addition, the results were compared in terms of combustion pressure, rate of heat release, $NO_x$ and soot emissions. It was found that combustion pressure was increased when injection timing was advanced. The rate of heat release of 6 hole nozzle was higher than that of 12 hole nozzle since the quantity of fuel impinged at the bottom of piston rim was different under different injection timing conditions. In the case of $NO_x$ emission, 6 hole nozzle generated more $NO_x$ emission than 12 hole nozzle. On the other hand, in the case of soot emission, 12 hole nozzle showed higher value than 6 hole nozzle because injected fuel droplets from multi-hole nozzle were coalesced.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.237-242
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• 2000

This study was carried out to optimize burner of the condensing gas boiler which can save energy by utilizing the latent heat of combustion gas and reduce pollutants emission. Three reasonable distances between burner and heat exchanger were decided through the experiments of model flat burner. The optimum burner geometry was determined from flame stability, pollutant emission characteristics and applicability to practical boiler system. The boiler designed by this research reaches turn-down ratio 5:1 in the domain of equivalence ratio 0.68∼0.85 and thermal efficiency of 98%. Emission of NOx and CO concentration was under 35ppm and 104ppm.

• Journal of Information Display
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• v.7 no.2
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• pp.22-25
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• 2006

This paper presents heating process for obtaining standing carbon nanotube emitters to improve field-emission properties from the screen-printed multiwalled carbon nanotube (MWCNT) films. In an atmosphere with optimum combination of nitrogen and air for heat treatment of CNT films, the CNT emitters can be made to protrude from the surface. This allows for high emission current and the formation of very uniform emission sites without special surface treatment. The morphological change of the CNT film by this technique has eliminated additional processing steps, such as surface treatment which may result in secondary contamination and damage to the film. Despite its simplicity the process provides high reproducibility in emission current density which makes the films suitable for practical applications.