• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.3
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• pp.218-223
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• 2019

To prevent the low heating effect of heating system caused by the high sheet resistance of CVD graphene, multi-layered graphene was laminated to implement a Transparent plane heating system with good optical properties of low-resistance. Low-resistance plane heating system implemented by $300{\times}400{\times}5mm$ heating plane laminated multi-layered CVD graphene film and PWM control system to drive efficient power. A plane resistance value of $85.5{\Omega}/sq$ was measured on average for 4-layer CVD graphene film used as a heating plane. Thus, the transfer by thermal film as the method of implementing low-resistance CVD graphene is reasonable. The experimental results of heat test show that an average heat-rise rate in low-resistance, transperent plane heating system using CVD graphene is $10^{\circ}C/min$ and has an optical transmittance rate of 86.44%. Therefore, the proposed heating system is applicable to large window glass and vehicle heating window-shild-glass.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.276-280
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• 2002

환경적ㆍ산업적으로 크게 문제되는 폐기물인 Steel 음료캔과 Aluminum 음료캔을 사용하여 기존의 콘크리트와 다른 다양한 관점에서 음료캔 발열콘크리트의 강도와 전기적 특성에 관하여 실험했다. 본 연구에서는 2002년 3월 8일부터 2002년 10월 9일 까지 장기간에 걸쳐서 계절이 바뀌는 자연현상에서 음료캔 발열콘크리트의 특성파악을 위한 전기ㆍ전도 특성과 축열효과 관점에서 저항률 변화를 계속 실험, 연구하였다.

• Journal of Sensor Science and Technology
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• v.6 no.5
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• pp.400-406
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• 1997

The electrical and physical characteristics of aluminum oxide and Pt thin films on it, deposited by reactive sputtering and DC magnetron sputtering, respectively, were analyzed with increasing annealing temperature($400{\sim}800^{\circ}C$) by four point probe, SEM and XRD. Under $600^{\circ}C$ of annealing temperature, aluminum oxide had the properties of improving Pt adhesion to $SiO_{2}$ and insulation without chemical reaction to Pt thin films and the resistivity of Pt thin films was improved. But these properties of aluminum oxide and Pt thin films on it were degraded over $700^{\circ}C$ of annealing temperature because aluminum oxide was changed into metal aluminum and then reacted to Pt thin films deposited on it. The thermal characteristics of Pt micro heater were analyzed with Pt-RTD integrated on the same substrate. In the analysis of properties of Pt micro heater, active area was smaller size, Pt micro heater had better thermal characteristics. The temperature of Pt micro heater with active area, $200{\mu}m{\times}200{\mu}m$ was up to $400^{\circ}C$ with 1.5watts of the heating power.

• Fire Science and Engineering
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• v.34 no.1
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• pp.66-71
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• 2020

The process of discharging batteries using salt water, when used for the disposal of a lithium-ion (Li-ion) batteries, is likely to cause a fire. However, there is a dearth of studies in the literature on the risk of fire while discharging mobile phone batteries in salt water. In order to investigate the possibility of fire by elucidating the discharge characteristics and the generation of heat, we conducted experiments by varying the concentration of the salt water, number of overlapping batteries, and type of the mobile phone batteries used as experimental specimen. The discharging voltage and the temperature of the batteries were measured, and the fire risk was predicted by analyzing the data. The results of the experiment showed that the higher the salt water concentration, the greater the discharge value of the mobile phone battery and the higher the exothermic temperature. Moreover, the exothermic temperatures of the overlapping batteries were higher than that of the single battery submerged in salt water. The highest exothermic temperature points of the battery occurred at the positive and negative poles.

• Transactions of the KSME C: Technology and Education
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• v.1 no.2
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• pp.179-186
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• 2013

Far-infrared radiation therapies are becoming more popular for blood circulation disorders, cardiovascular disease, skin diseases, inhibit cancer cell, etc replacing conventional operations. In this research, thermal characteristics of heating part in panel radiators, which is effective on the blood circulation disorders were experimentally analyzed. The heating line supplies heat energy to insulation coatings with heat flux of $150mW/m^2$ in normal status and as a result the coatings reached 20% of the heating line temperature. In other words, the insulation itself could increase surface temperature of heating plates by 20% and raise thermal time constant promote blood circulation effect. We also found that space arrangement of the heating lines was an important factor in designing heating parts and both coefficient of heat conduction and density of the heating plate should be also considered for superimpose of thermal diffusion.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.1
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• pp.90-94
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• 2023

Carbon fiber(CF) with excellent thermal conductivity and electrical conductivity is attracting attention as an alternative material because metal heating elements have problems such as high heat loss and fire risk. However, since CF is oxidized and disconnected at about 200℃ or higher, the application of heating elements is limited, and CF heating elements in the form of vacuum tubes are currently used in some commercial heaters. In this work, polyimide(PI) with high heat resistance was coated on the surface of carbon fiber by electrophoretic deposition to prevent oxidation of CF in the atmosphere without using a vacuum tube, and the coating thickness and heat resistance were investigated according to the applied voltage. The heater made by connecting the PI-coated CF heating elements in series showed stable heating characteristics up to 292℃, which was similar to the heating temperature result of the heat transfer simulation. The PI layer coated by the electrophoretic deposition method is effective in preventing oxidation of CF at 200℃ or higher and is expected to be applicable to various heating components such as secondary batteries, aerospace, and electric vehicles that require heat stability.

• Journal of Power System Engineering
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• v.10 no.1
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• pp.71-76
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• 2006

This paper aims to study several type heaters which are mica heater, film heater, quartz heater and rod heater and to get an temteraturel and electrical characteristics. These four type heaters have a merit in many fields than present electric heater with nichrome wire. Carbon and mica plate heater have higher heat efficiency and less electromagnetic waves. Also it has been reported that far infrared ray emission from this heater is good for our health. Additionally heating element is thin and lighter plate. For these reasons, they will be widely used to various application such as room-heating or manufacturing goods. Experimental result confirmed that when 220V current authorized, the temperature, electric current, electric power and the resistance rise to stationary state in early stage. Moreover, the temperatures and electric characteristics show a good stability.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.05a
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• pp.47-50
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• 2003

잉크젯 헤드의 발열체에 적용하기 위해 $poly-Si/SiO_2/Si$ 의 다층기판 위에 결정화된 안정한 $SiO_2$ 코발트 실리사이드 박막을 증착하여 발열체를 제작하고 이들 발열체의 구조적 형상과 온도저항계수 등 전기적 특성을 조사하였다. $SiO_2$ 코발트실리사이드 박막의 형성은 금속 Co 박막을 급속 열처리장치를 이용하여 $800^{\circ}C$에서 20 초 동안 질소 분위기에서 열처리하여 실리사이드 박막을 형성하였다. 발열체의 온도저항계수 값은 약 $^0.0014/{\circ}C$ 값을 얻을 수 있었다. 인가전압 10V, 주파수 10 kHz 및 펄스간격 $1\mu\textrm{s}$ 인가시 발열체의 순간전력은 최대 2 watt를 나타내었다.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.1
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• pp.134-142
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• 2007

In this study the physico-chemical characteristics of solid waste and the thermagravimetric analysis of waste investigated. It was found that the combustible component, water and ash were 61%, 32%, 7% respectively. The amount of combustible component was much higher than those of others. It was shown that the total carbon and hydrogen of the waste 94% and the high heating value was 2897,883(Kcal/kg). The thermagravimetric analysis showed that the weight loss of wastes occurred as temperature increased, and the rate was higher in the temperature range of $300^{\circ}C$ to $500^{\circ}C$.

• Magazine of the Korea Concrete Institute
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• v.6 no.5
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• pp.203-212
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• 1994

The setting and hardening of concrete is accompanied by nonlinear temperature distribution caused by developing heat of cement hydration. This leads to tensile stresses that may exceed the strength of the young concrete, and cracks occur. In this present study, the heat of hydration characteristics are obtained from a study in which insulated concrete cubes were tested. Based on test results, concrete heat of hydration characteristics according to unit weight cement and flyash replacement quantity are determined, then employed in a numerical temperature analysis that consider both environmental interaction and concreting phases. The numerical results are performed by ADINA - T. The analytical results are in good agreement with experimental data.