• Journal of the Korean Society of Combustion
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• v.8 no.1
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• pp.17-24
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• 2003

The conventional regenerative system has a high thermal efficiency as well as energy saving using the high preheated combustion air. in spite of these advantages, it can not avoid high nitric oxide emissions. Recently, flameless combustion has received much attention to solve these problems. In this research, numerical analysis is performed for flow-combustion phenomena in the self regenerative burner. In this analysis we used Fluent 6.0 code. the that is developed for commercial use, Methane gas is used as a fuel and two-step reaction model for methane and Zeldovich mechanism for NO generation are used. the velocity of the preheated combustion air is used as a parameter and we analyze the characteristics of flow-field, temperature distributions and NO emissions. Due to the increased recirculation rate, the maximum temperature of flame is significantly increased and NOx emissions is reduced.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.7
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• pp.588-594
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• 2001

The purpose of this study is to investigate the thermal and hydrodynamic characteristics of the channel in corrugated plate type heat exchangers numerically. Numerical work has been conducted using the Reynolds Stress Model(RSM) by utilizing the commercial finite-volume code, FLUENT. Based on this model, the dependence of heat transfer and friction factor on geometrical parameters have been investigated. It is found that larger corrugation angle give higher values of heat transfer coefficients and friction factors. As the reynolds number increases, the heat transfer coefficient also increases. It is also observed that the heat transfer coefficient reaches maximum while the friction factor stays relatively low at same corrugation angle. Through the analysis, it is found that the optimum corrugation angle for the heat exchanger performance exists. It is noted that the flow repulsions at the contact point of the two fluid streams make the low mixing more active for larger corrugation angle and high reynolds number.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.98-103
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• 2008

The glass for crystalline PV module fabrication should have high thermal and mechanical resistance to environmental also have high transparency. In this paper, we analyze the optical characteristics of glasses for photovoltaic module application. The transmittance of several glasses are measured. The effects of texturing on low iron glass, glass thickness, anti-reflective glass, photocatalyst-treated glass and special glass are compared each other. Then this will give some information to select PV glass for manufacturing. The detailed analysis is described in the following paper.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.452-454
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• 2002

In case the overload of an existing power line is expected as the consumption of electric power increase, we substitute STACIR/AW which has better thermal characteristic for ACSR. That can approximately double the transmission capacity. In that case the mechanical characteristics of STACIR/AW should meet the design condition of the existing tower. However, the strength of invar in STACIR/AW is lower than that of steel in ACSR, which makes it difficult to keep the safety of a conductor specially in a long span In this regard, this paper presents the new conductor model using the AMC and the analysis of its characteristics.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.878-885
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• 2011

A kinematically-hybrid 5-axis machine tool is analyzed from the perspective of machine tool design. Its kinematic characteristics are pointed out, which should be considered during the conceptual design process. A result of the structural analysis of the machine is presented, which is performed during the detailed design process. It is also presented how we improve the thermal characteristics of the machine tool by changing the installation position of the actuators.

• KSBB Journal
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• v.14 no.3
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• pp.273-278
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• 1999

The molecularly imprinted polymers(MIPs) synthesized at various polymerization conditions were examined as ibuprofen receptors in terms of binding characteristics. The 4-vinylpyridine polymers had 1.2 times higher adsorption capability for (S)-(+)-ibuprofen than the methacrylic acid polymers. The methacrylic acid polymers synthesized by UV radiation had 1.9 times higher selectivity for (S)-(+)-ibuprofen compared to those by thermal initiation. Effects of various solvents for binding were also examined in this research. According to the Scatchard analysis, the (S)-(+)-ibuprofen artificial receptors had two different kinds of binding sites for (S)-(+)-ibuprofen while having only single kind of binding site for ketoprofen. The binding sites of (S)-(+)-ibuprofen, n were calculated as 4.3~4.9 $\mu$mol/g and the dissociation constants, $K_D$ were 0.68 mM for the specific binding.

• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.97-104
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• 2002

The conventional regenerative system has a high thermal efficiency as well as energy saving using the high preheated combustion air. in spite of these advantages, it can not avoid high nitric oxide emissions. Recently, flameless combustion has received much attention to solve these problems. In this research, numerical analysis is performed for flow-combustion phenomena in the self regenerative burner. In this analysis we used Fluent 6.0 code. the that is developed for commercial use, Methane gas is used as a fuel and two-step reaction model for methane and Zeldovich mechanism for NO generation are used. the velocity of the preheated combustion air is used as a parameter and we analyze the characteristics of flow-field, temperature distributions and NO emissions. Due to the increased recirculation rate, the maximum temperature of flame is significantly increased and NOx emissions is reduced

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.6
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• pp.903-909
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• 2012

This study analyzed the temperature distribution in DPF with five partitioned electric heaters. The temperature distribution in DPF is an important design factor for regeneration and durability of filter. The design Factors that influence the temperature distribution in DPF there are several. In this study, the characteristics of temperature distribution in DPF were analyzed according to the following changes. First, the thermal conductivity of the filter was analyzed about effect on the durability of the filter. Second, the length from exhaust manifold to inlet of DPF was analyzed about effect on the temperature distribution in DPF. The boundary conditions of analysis has been verified with comparison to the results of existing experimental study and the numerical analysis. Based on the identified boundary condition, on assuming the condition of the actual driving, the temperature distribution in DPF was analyzed according to material properties of filter and the position of DPF.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.5
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• pp.398-410
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• 2001

The flow and heat transfer characteristics for three-dimensional mixed convection flows in a radiator flat tube with U--shaped grooves are analyzed numerically. The flow and temperature fields are calculated by using the modified SIMPLE algorithm for irregular geometry. One tube specification among the various flat tube exchangers is recommended by considering the heat transfer and pressure drop. The effects of variation of coolant flow conditions and external air conditions on the flow and the thermal characteristics for the selected tube are investigated. the results show that inlet velocity of coolant flow is the very important factor in heat transfer and pressure drop, and top side is better position than the others as fin cleave to tube.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.352-358
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• 2004

The firing reaction and calcination characteristics of the waste shellfish were examined for the future use as absorbent. The weight variation was measured according to thermal-decomposition using TGA and observed variation of the phase. The qualitative and quantitative analysis of the sample were performed using XRD and the structural analysis, SEM. The results of TGA and XRD experiments showed that the almost all of the raw Corbicula Japonica and Ostrea virginjca were changed from calcite to lime by firing and calcination reaction. The result of SEM experiment showed that the plate type of the raw sample was changed to circle type, so the surface area ratio was increased. Above results suggested that waste shellfish were usable as absorbent in the viewpoint of the reuse of resource and the decrease of environmental pollution.