• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2606-2611
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• 2003

Comprehensive study on the control system design for a RTP process has been conducted. The purpose of the control system is to maintain maximum temperature uniformity across the silicon wafer achieving precise tracking for various reference trajectories. The study has been carried out in two stages: thermal balance modeling on the basis of a semi-empirical radiation model, and optimal iterative learning controller design on the basis of a linear state space model. First, we found through steady state radiation modeling that the fourth power of wafer temperatures, lamp powers, and the fourth power of chamber wall temperature are related by an emissivity-independent linear equation. Next, for control of the MIMO system, a state space modeland LQG-based two-stage batch control technique was derived and employed to reduce the heavy computational demand in the original two-stage batch control technique. By accommodating the first result, a linear state space model for the controller design was identified between the lamp powers and the fourth power of wafer temperatures as inputs and outputs, respectively. The control system was applied to an experimental RTP equipment. As a consequence, great uniformity improvement could be attained over the entire time horizon compared to the original multi-loop PID control. In addition, controller implementation was standardized and facilitated by completely eliminating the tedious and lengthy control tuning trial.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.1
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• pp.28-33
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• 2022

The heating roller of an actual pulse output device (POD) production facility is composed of a steel roller and a rubber roller. The time to reach a specific temperature and the temperature distribution on the roller surface were analyzed and compared according to the change in the number of cartridge heaters inside the heating roller. In this analysis, a steady-state thermal analysis of a steel roller was performed for the cases of a 5-cartridge heater and 9-cartridge heater. Finite element analysis was applied with reference to the surface temperature data of the heating roller during operation and the calorific value of the cartridge heater. Using the 9-cartridge heater, faster target temperature achievement and more uniform temperature distribution were confirmed than for the 5-cartridge heater.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.341-348
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• 1991

An efficient tool to deal with a multi-dimensional radiative heat transfer is in strong demand to analyze various thermal problems combined either with other modes of heat transfer or with combustion phenomena. The current study examined the discrete ordinates method (DOM) for a coupled radiative and conductive heat transfer in rectangular enclosures in which either nonscattering or scattering medium is present. The results were compared with the other benchmarked approximate solution. The efficiency and accuracy of the DOM were thus validated.

• Journal of the Korean Vacuum Society
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• v.4 no.1
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• pp.32-39
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• 1995

SnO2/AI/Ag/AI/SnO2층 구조로 이루어진 열처리 가능한 열선반사막을 직류 스퍼터링법에 의해 soda-lime silicate 유리위에 형성시켰다. 이 코팅유리를 $650^{\circ}C$에서 열처리하면 가시광선 투과율 85%이상, plasma wavelength 970nm 이하를 얻을 수 있었다. 따라서 이 구조의 막은 유리 곡가공에 견디는 열적 안정성을 나타내었으며, 코팅유리의 열처리에 따른 전기적 특성 및 열적 안정성은 각각 Ag와 AI층의 두께에 의존하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1991.10a
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• pp.18-22
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• 1991

Far Infrared radiators should have functionality to convert thermal energy into electron wave. In order to apply the Far Infrared to the substance, the absorption characteristics of the substance should be considered. In this paper, interrelation of emissivity with emission energy according to temperature in the range of 2.5$\mu$m to 25$\mu$m after the transition element oxides (MnO2, Fe2O3, CuO, Co3O4) of first grade reagent were molded in press, then they were calcinated in 1050˚C, and they were used as samples.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.6
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• pp.32-40
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• 1995

Far Infrared radiators should have functionality to convert thermal energy into an electromagnetic wave. In order to apply the Far Infrared to the substance, the absorption characteristics of the substance should be considered. In this paper, interrelation of emissivity with emission energy according to temperature in the range of [$2.5\mu\textrm{m}$] to 25[$\mu\textrm{m}$] after the transition element oxides (MnO2, Fe2O3, CuO, Co3O4) of first grade reagent were molded in press, then they were sintered in [$1050^{\circ}C$], and they were used as samples.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.614-617
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• 2009

Elastomeric Flexible Cellular Insulation is widely used in construction fields to prevent condensation and frozen pipes, reduce energy, and improve insulation. However, when Elastomeric Flexible Cellular Insulation has been installed in buildings in Korea, there was no standardization, which resulted in heat loss Therefore, insulation design standards need to be developed and from these standards, pipe insulation should be improved to increase its efficiency. This study estimates temperature and surface-emissivity according to the thickness of insulation to evaluate thermal performance.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.3-6
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• 2012

Analysis method for the radiation heat transfer from the duct burner flame to the heat exchanger in a Heat Recovery Steam Generator (HRSG) was presented to supplement the existing thermal design process. Flame on a burner and a heat exchanger were postulated as imaginary planes and flame temperature, surface and emissivity was simplified in a aspect of engineering approach. The calculated local flame radiative heat flux on the heating surface was compared with the heat flux of 3-atomic gas radiation and convection.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.563-568
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• 2005

Land surface temperature (LST) for large areas can only be derived from surface-leaving radiation measured by satellite sensors. These measurements represent the integrated effect of the surface and are superior to point measurements on the ground, e.g. in Urban Heat Island. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is an imaging instrument that is flying on the NASA's Terra satellite launched in December 1999. ASTER acquires 14 spectral bands and can be used to obtain detailed datas of land surface temperature, emissivity, reflectance and elevation. Spatial resolution of 90m of TIR channels of ASTER is useful when we analyze the spatial variations of surface heat fluxes in urban areas. The purpose of this study is to extract the LST using ASTER TIR channels.

• Elastomers and Composites
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• v.57 no.2
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• pp.62-72
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• 2022

Passive daytime radiative cooling (PDRC) is attracting increasing attention as an eco-friendly technology that can save cooling energy by not requiring an external power supply. An ideal PDRC structure should improve solar reflectance and emissivity within the atmospheric spectral window. Early designs of photonic crystal materials demonstrated the benefits of PDRC. Since then, functional arrangements of polymer-based radiative cooling materials have played an important role and are rapidly expanding. This review summarizes the known inorganic, organic, and hybrid materials for PDRC. The review also provides a complete understanding of PDRC and highlights its practical applications.