• Journal of Surface Science and Engineering
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• v.53 no.5
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• pp.227-231
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• 2020

This article investigated the effects of stainless steel plate-patterns bonded to aluminum frypan on the thermal distortion and surface temperature of the frypan during gas or induction heating. Two different stainless steel plate-patterns were employed: type A contains only circular holes and type B has not only circular holes but also vacant spaces of 0.5 mm thick and 40 mm long straight line crossing 60 mm long curved line. The bottom of the frypan was distorted during heating when type A stainless steel plate-bonded frypan while no significant thermal distortion was observed for type B stainless steel plate-bonded frypan during heating. Temperature of the frypan surface showed the same trend during gas heating, irrespective of stainless steel plate-patterns. During induction heating, however, the frypan with type B stainless steel plate-pattern showed lower surface temperature than the frypan with type A stainless steel plate-pattern. It is concluded that Type B stainless steel plate-pattern with circular holes and vacant spaces of lines is very effective for minimizing a thermal distortion and lowering the surface temperature of an aluminum frypan during induction heating.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.779-782
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• 1990

Recently batch type cold rolling processes have been replaced by continuous annealing type processes for cold rolled sheets of mild steel and high strength steel in order to obtain higher productivity, labor saving. In the continuous annealing line, it is very important to maintain the target steel strip temperature at the exit side of each furnace. The automation system of continuous annealing line is based on a hierachical composition. This paper shows how to preset the set value of furnace temperature control for the heating section in a continuous annealing line. Saying in other words, this paper presents the development of an adaptive control approach to control the exit strip temperature in the continuous annealing line. There are three parts in this approach; one is a process modelling and another is recursive parameter estimation and the other is a design of temperature controller.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1138-1139
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• 2015

본 논문은 디젤엔진용 Heating Urea - SCR (Selective Catalytic Reduction) 시스템을 구성함에 있어 변화되는 Euro-6 규제에 근간하여 Electrically Heated Line에 대한 저항력, 전도성, 온도 특성 등 전기적 설계 기법에 관해 서술하였고 Heating Urea-SCR Line을 위한 열선 설계, 전기적 및 물리적 상수에 대해 서술하였다. 이러한 전기적 설계 기법이 향후 양산을 위한 가격, 성능, 신뢰성 부분 및 제품의 경쟁력 요소에 가장 핵심이 되는 부분이다. 본 논문에서는 이러한 설계 기법의 구현을 위해 설계 절차와 설계 결과 도출을 위한 프로그램을 구현하였다. 향후 시제품의 모의실험과 실제 제품 제작을 수행 예정이고 본 논문의 설계 결과와 실제품 결과의 지표를 비교하여 최적의 Heated Line을 개발 하고자 한다.

• Journal of Energy Engineering
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• v.20 no.4
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• pp.330-337
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• 2011

In these days, the gas or kerosene boiler was usually used as heating system. This study was carried out to investigate the merits of X-L pipe boiler with electric heat line that was specially manufactured. The electric heat line was inserted into inside of X-L pipe and voltage was impressed to electric heat line and, as a result, temperature of X-L pipe filled with heat medium was increased. As changing the number of electric heat line and voltage, the characteristics of X-L pipe boiler and its mechanism on heat generation were studied. Furthermore, the economical efficiency was evaluated by comparing heating cost of X-L pipe boiler with those of kerosene boiler and natural gas boiler, respectively. As the results, it was confirmed that heating cost of X-L pipe boiler was showed as 28% of kerosene boiler and 58% of natural gas boiler.

• Journal of Power System Engineering
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• v.20 no.5
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• pp.46-51
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• 2016

The TMCP steel has expanded in the marine structure during manufacturing process because of its excellent weld-ability and impact toughness. In the case of merchant ships, coverage of TMCP steel has been used widely on over DH36 Classifications material. The line heating process is applied to the outer surface of the steel plate for the shipbuilding. In this study, We compared between TMCP and normalizing steel for shipbuilding by analyzing some basic data through performing the natural cooling after the line heating. The experimental results show the angular misalignment changes in line heating. Heated surface of normalizing steel material expanded to $-0.3^{\circ}$ and reduced to $+0.2^{\circ}$ after cooling. And during cooling at $194^{\circ}C$ for 1,500 seconds, Angular Misalignment began from - direction to + direction, passed the critical point to the default at 2,200 seconds and did not take place any more at $103^{\circ}C$ after the 2,700 seconds. Angular Misalignment results of TMCP steels and Normalizing steel material show same angular misalignment lasted 1,200 seconds, TMCP steel has given more expansion and contraction angle which is $0.2^{\circ}$ than that of the Normalizing steel. Length difference between expansion and contraction is about 0.3 mm.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.3
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• pp.360-366
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• 2018

In shipyards hull forming is performed by the line heating method using a gas torch and by cold treatment using a roll-press. However, this forming process has some issues, such as difficulties in controlling and accurately estimating the amount of the heat input, as well as a harsh working environment due to exposure to loud noises and air pollution. The induction heating method, which is introduced in this paper, exhibits good control and allows for the estimation of precise heat input. Also, workers can carry out the induction heating in a comfortable working environment. In this research, the induction heating simulation, which consists of electro-magnetic, heat transfer and thermal elasto-plastic analysis, was developed and modified through induction heating experiments. Finally, the effective heating coil was designed for the automatic hull forming system based on the results of induction heating simulation. For the purposes of a future study, if an algorithm to obtain optimal working conditions is developed, automatic systems for hull forming can then be constructed.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.63-70
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• 2011

In the present study, we developed optimal heat supply algorithm which minimizes the heat loss through the distribution pipe line in group energy apartment. Heating load variation of group energy apartment building in accordance with outdoor air temperature was predicted by the correlation obtained from calorimeter measurements of whole households of apartment building. Supply water temperature and mass flow rate were conjugately controlled to minimize the heat loss rate through distribution pipe line. Group heating apartment located in Hwaseong city, Korea, which has 1,473 households divided in 4 regions, was selected as the object apartment for verifying the present heat supply control algorithm. Compared to the original heat supply system, 10.4% heat loss rate reduction can be accomplished by employing the present control algorithm.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.77.3-78
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• 2021

Measuring radiative loss from the solar chromospheric lines like Ha line, Ca II 8542 line helps to infer the exact amount of non-thermal heating in the solar atmosphere. By courtesy of the multi-layer spectral inversion, it is able to determine the radiative loss in the upper and lower chromosphere. Consequently, we found that the radiative loss is around 10 kW/m², which is consistent with previous studies. Comparing the radiative loss at the upper and lower chromosphere, the loss at the lower chromosphere is larger than that of upper chromosphere and tends to spread all over the field of view while the loss in the upper chromosphere tends to be localized. We hope to find a hint for specific non-thermal heating process to explain the chromospheric radiative loss.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.66.2-66.2
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• 2013

As part of the DIGIT key program, we observed GSS30-IRS1, a Class I object located in Ophiuchus (d=125 pc), with Herschel-PACS. More than 70 lines were detected in 50-200 micron band including CO, OH, H2O, and [OI]. All lines, except for [OI], were detected only at the central spaxel of $9.4^{{\prime}{\prime}}{\times}9.4^{{\prime}{\prime}}$ while the [OI] emission is extended along the NE-SW direction. One interesting feature in GSS30-IRS1 is that the continuum is extended beyond PSF, unlike line emission. It suggests that the external heating is important in GSS30-IRS1. For detail analysis of line fluxes, we apply the non-LTE LVG model, RADEX as well as simple rotational diagrams. We also use the Monte Carlo radiative transfer package, RADMC-3D to understand the heating mechanism of dust grains around GSS30-IRS1. We will discuss about heating and cooling processes associated with GSS30-IRS1.

• Proceedings of the KWS Conference
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• 2008.05a
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• pp.29-29
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• 2008