• 대한전기학회논문지:전력기술부문A
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• 제50권9호
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• pp.406-410
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• 2001

This paper develops an efficient evolutionary programming based algorithm for solving the environmentally constrained economic dispatch problem in thermal power system. The proposed algorithm can deal with the power balance constraints and the emission constraints which are equality and inequality constraints, respectively. Numerical results show that the proposed algorithm can provide superior solutions within reasonable time through its application to a test system.

• 한국전기전자재료학회논문지
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• 제11권10호
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• pp.918-923
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• 1998

Poly-silicon thin film transistors were fabricated on quartz substrates by high temperature processes. Electrical characteristics were measured and compared for 3 transistor structures of Standard Inverted Gate(SIG), Lightly Doped Drain(LDD), and Dual Gate(DG). Leakage currents of DG and LDD TFT's were smaller that od SIG transistor, while ON-current of LDD transistor is much smaller than that of SIG and DG transistors. Temperature dependence of the leakage currents showed that SIG and DG TFT's had thermal generation current at small drian bias and Frenkel-Poole emission current at hight gate and drain biases, respectively. In case of LDD transistor, thermal generation was the dominant mechanism of leakage current at all bias conditions. It was found that the leakage current was closely related to the reduction of the electric field in the drain depletion region.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2126-2130
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• 2008

Gasoline engine have proved its utility in light, medium and heavy duty vehicle in every sector of the world community. The concern about long term availability of petroleum and the increasing threat for the environment by the increasing load of vehicular emission, compel the technology to upgrade itself for meeting the challenges. CNG is environmentally clean alternative to the existing SI Engines with out much change in the hardware. Many researchers have found this as a potential substitute to meet the energy requirement. Higher octane number and higher self ignition temperature make it a good gaseous fuel. Although power output is slightly lesser than the gasoline it's thermal efficiency is better than the gasoline for the same SI Engine. Results showed that reduced CO, hydrocarbon emissions is a favorable outcome, with slight increase in $NO_x$ emission when compared with gasoline fuel to dual fuel mode in the existing SI Engines.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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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.

• 한국자동차공학회논문집
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• 제8권2호
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• pp.57-63
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• 2000

This paper deals with a study on combustion and emission characteristics of a direct injection diesel engine dual fueled with natural gas. Dual fuelling systems tend to emit high unburned fuel especially at low load, resulting in a decreased thermal efficiency. This is because natural gas-air mixtures are too lean for flame to propagate under low load conditions. Suction air quantity and injection timing controls are very useful to improve emissions and thermal efficiency at low load.

• 한국표면공학회지
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• 제45권5호
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• pp.193-197
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• 2012

The influence of annealing process in an $O_2$ atmosphere on the photoluminescence (PL) spectra properties of ZnS nanowires has been investigated. ZnS nanowires with the diameters approximately 100 nm and the lengths a few tens micrometers were synthesized by evaporating ZnS powders on Si substrates while using an Au thin film as a catalyst. ZnS nanowires had an NBE emission band at 430 nm in the violet region. The emission intensity was improved drastically by a process in which ZnS nanowires were heat-treated at $500^{\circ}C$ in an $O_2$ atmosphere for 45 minutes.

• 천문학회보
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• 제43권2호
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• pp.52.2-52.2
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• 2018

The shape of a galaxy's spectral energy distribution ranging from ultraviolet (UV) to infrared (IR) wavelengths provides crucial information about the underlying stellar populations, metal contents, and star-formation history. Therefore, analysis of the SED is the main means through which astronomers study distant galaxies. However, interstellar dust absorbs and scatters UV and optical light, re-emitting the absorbed energy in the mid-IR and Far-IR. I present the updated 3D Monte-Carlo radaitive transfer code MoCafe to compute the radiative transfer of stellar, dust emission through a dusty medium. The code calculates the emission expected from dust not only in pure thermal equilibrium state but also in non-thermal equilibrium state. The stochastic heating of very small dust grains and/or PAHs is calculated by solving the transition probability matrix equation between different vibrational, internal energy states. The calculation of stochastic heating is computationally expensive. A pilot study of radiative transfer models of SEDs in clumpy (turbulent), galactic environments, which has been successfully used to understand the Calzetti attenuation curves in Seon & Draine (2016), is also presented.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.50-50
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• 2011

The aluminum nitride films were prepared by RF magnetron sputtering using an AlN ceramic target. The crystallinity, grain size, Al-N bonding and thermal conductivity were investigated in dependence on the plasma power densities (4.93, 7.40, 9.87 W/$cm^2$) during sputtering. High thermal conductivity is important properties of A1N passivation layer for functioning properly in thermal inkjet printhead. The crytallinity, grain size, Al-N bonding formation and chemical composition were observed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. The AlN thin film was changed from amorphous to crystalline as the power density was increased, and the largest grain size appeared at medium power density. The near stoichiometry Al-N bonding ratio was acquired at medium power density. So, we know that the AlN thin film had better thermal conductivity with crystalline phase and near stoichometry Al-N bonding ratio at 7.40 W/$cm^2$ power density.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.208-213
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• 2011

In the former study, it is obtained that thermal storage effect of the apartment structure is the disadvantage to maintain comfort indoor thermal environment. However, because the thermal storage effect can be changed of its aspect in heating season, field measurement at the same apartment with the measurement in summer season was conducted in winter season. As results, thermal storage effect of apartment structure was the disadvantage in winter season, too.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.1-3
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• 2013

The premixed combustion system applying exhaust gas recirculation was investigated to achieve the low pollutant emission and the high thermal efficiency. In this study, it was studied the effects of EGR on the thermal efficiency, $NO_x$ and CO emissions with various EGR ratios and equivalence ratios. As results, when equivalence ratio was increased, thermal efficiency increased and $NO_x$ and CO concentration increased. When EGR was applied, $NO_x$ and CO concentration decreased and thermal efficiency increased. Especially, in the case of 15% of EGR ratio at 0.85 of equivalence ratio, $NO_x$ and CO concentration will be a smaller than these of a current operating condition of the boiler and thermal efficiency was about 1.7% higher.