• 제목/요약/키워드: 발열 특성

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A Study on the Thermal Characteristics Depending on Poor Contact of Wire Connection Part in Terminal Block (단자대 전선접속개소의 접촉불량에 따른 발열특성에 관한 연구)

  • Park, Sang-Min;Jee, Seung-Wook;Kim, Si-Kuk;Lee, Chun-Ha
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.11a
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    • pp.48-51
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    • 2011
  • 본 논문은 나사조임 단자대 내에 접속되는 전선의 접촉불량에 따른 발열특성을 분석하고자 단자대 접속개소의 조임토크를 KS C 2625에서 규정한 정상조임토크와 인위적인 불량조임토크를 변수로 설정하여 조임토크의 크기별로 동일한 부하를 인가한 후, 열화상카메라를 이용하여 접속불량에 따른 발열특성을 비교 분석하였다.

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Temperature performance improvement of SMPS using thermal simulation (열 해석을 이용한 SMPS 온도 특성 개선)

  • Na, Tae-Kwon;Jung, Jee-Hoon;Choo, Jong-Yang;Kwon, Joong-Gi
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.183-185
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    • 2008
  • 재택근무와 소규모 창업 등 사무 환경의 변화 에 따라 프린터와 복합기의 소형화가 요구 되고 있다. 이러한 소형화에 의해 프린터 내부의 발열 요소들이 제한 된 공간에 배치되어, 기기 내부의 열 유동 및 발열 개선은 제품의 수명과 안정성 확보를 위한 중요 사항이 되었다. 본 논문에서는 프린터와 복합기의 내부 요소 중 주요 발열원인 전원 공급 장치에 대하여 Computational fluid dynamics (CFD) software 인 ICEPAK을 이용하여 중요 부품의 배치 조건에 따른 대류 와 온도 특성을 확인 하고, 최적화 된 부품 배치 방법을 제안한다. 또한 제안하는 부품 배치 방법을 적용한 초박형 프린터용 50W 급 전원 공급 장치를 제작하여 실제 온도 특성이 개선됨을 확인한다.

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Natural Convection in a Horizontal Cylindrical Annulus Enclosing Heat Generating Core (發熱核 주위의 수령圓環 에서의 자연대류)

  • 장근식;오세윤
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.9 no.5
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    • pp.663-676
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    • 1985
  • 수평원통형의 복합유동층에서의 층류자연대류를 수치적으로 연구하였다. 외측의 동심원환이 내 의 발열유체로 형성된 원통형 핵을 둘러싸고, 그 사이에 두께가 유한하거나 두께를 무시할 수 있 는 간막이 벽이 존재한다. 유동특성과 열전달에 관한 매개변수적 고찰을 시행하거나 직경비, Prandt1수, 발열강도에 기준을 둔 Rayleigh수 등의 영향을 이해하게 되었다. 간막이 벽의 두께나 열전도의 효과도 제한된 범위 안에서 고려하였다.

Fever Phobia: A Survey of Children's Parents in a Pediatric Outpatient Clinic (소아청소년과 외래를 방문한 부모들의 발열공포와 관련 요인)

  • Choi, Ae-Ran;Kim, Jin Sun
    • Child Health Nursing Research
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    • v.20 no.2
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    • pp.113-122
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    • 2014
  • Purpose: Purposes of this study were to identify the level of parental fever phobia and to investigate the relationship between level of parental concern about fever and related variables. Methods: Participants were 151 parents of children who visited a pediatric outpatient clinic. A selfreported structured questionnaire was used for data collection and data were analyzed using descriptive statistics and ${\chi}^2$-test. Results: Almost half of participants defined a minimum temperature for fever as $37.8^{\circ}C$ and a minimum temperature for high fever as $38.9^{\circ}C$. About 75% of participants identified harmful effects of fever as seizure and brain damage, were 'very worried' about fever, measured their child's temperature every hour or less, provided tepid massage and woke children to give antipyretics during febrile illness. There were significant relationships between level of parental concerns about fever and prior experience of febrile seizures, and/or being parents of a single child. Conclusion: Results indicate that fever phobia is prevalent among parents. Further studies are needed to develop and evaluate childhood fever management educational programs for parents. Considering health care providers as a primary information resource about fever management, health care providers should play a vital role to reduce parental unrealistic concerns about fever.

A study on the fabrication of heatable glass using conductive metal thin film on Low-e glass (로이유리의 전도성 금속박막을 이용한 발열유리 제작에 관한 연구)

  • Oh, Chaegon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.105-112
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    • 2018
  • This paper proposes a method for fabricating heatable glass using the conduction characteristics of metal thin films deposited on the surface of Low-e(Low emissivity) glass. The heating value of Low-e glass depends on the Joule heat caused by Low-e glass sheet resistance. Hence, its prediction and design are possible by measuring the sheet resistance of the material. In this study, silver electrodes were placed at 50 mm intervals on a soft Low-e glass sample with a low emissivity layer of 11 nm. This study measured the sheet resistance using a 4-point probe, predicted the power consumption and heating value of the Low-e glass, and confirmed the heating performance through fabrication and experience. There are two conventional methods for manufacturing heatable glass. One is a method of inserting nichrome heating wire into normal glass, and the other is a method of depositing a conductive transparent thin film on normal glass. The method of inserting nichrome heating wire is excellent in terms of the heating performance, but it damages the transparency of the glass. The method for depositing a conductive transparent thin film is good in terms of transparency, but its practicality is low because of its complicated process. This paper proposes a method for manufacturing heatable glass with the desired heating performance using Low-e glass, which is used mainly to improve the insulation performance of a building. That is by emitting a laser beam to the conductive metal film coated on the entire surface of the Low-e glass. The proposed method is superior in terms of transparency to the conventional method of inserting nichrome heating wire, and the manufacturing process is simpler than the method of depositing a conductive transparent thin film. In addition, the heat characteristics were compared according to the patterning of the surface thin film of the Low-e glass by an emitting laser and the laser output conditions suitable for Low-e glass.

Heating Characteristics of Planar Heater Fabricated with Different Mixing Ratios of MXene-CNT-WPU Composites (MXene-CNT-WPU 복합소재 기반 면상발열체의 배합 비율에 따른 발열 특성)

  • Hyo-Jun, Oh;Quy-Dat, Nguyen;Yoonsik, Yi;Choon-Gi, Choi
    • Clean Technology
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    • v.28 no.4
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    • pp.278-284
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    • 2022
  • This study presents an excellent planar heater based on low-dimensional composites. By optimizing the ratio of 1D carbon nanotubes (CNT) and 2D MXene (Ti3C2TX), it is possible to create a planar heater that has superior electrical conductivity and high heat generation characteristics. Low-dimensional composites were prepared by mixing CNT paste and MXene solution with eco-friendly waterborne polyurethane (WPU). In order to find the optimal mixing ratio for the MXene-CNT-WPU composites, samples with MXene to CNT weight ratios of 3:1, 1:1, 1:3, 1:7, and 1:14 were investigated. In addition to these different weight ratios, 5 wt% WPU was equally applied to each sample. It was confirmed that the higher the weight ratio of CNT, the lower the sheet resistance and the higher the heating temperature. In particular, when the MXene-CNT-WPU planar heater was fabricated by mixing MXene and CNT at a weight ratio of 1:7 and 1:14, the heating temperature was higher than the heating temperature of a CNT-WPU planar heater. These characteristics are due to the optimized mixture of the 1D materials (CNT) and the 2D materials (MXene) causing the formation of a flat surface and a dense network structure. The low-dimensional composites manufactured with the optimized mixing ratios found in this study are expected to be applied in flexible electronic devices.

Temperature Maintenance of an ITO Nanoparticle Film Heater (ITO 나노입자 면상발열체의 온도유지에 대한 연구)

  • Yang, Kyungwhan;Cho, Kyoungah;Im, Kiju;Kim, Sangsig
    • Journal of IKEEE
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    • v.20 no.2
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    • pp.171-173
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    • 2016
  • In this study, we fabricate a high efficiency heater consisting of the indium tin oxide (ITO) nanoparticle (NP)-paste and polydimethylsiloxane (PDMS) and investigate the effect of PDMS on temperature maintenance of the heater through the comparison with the PDMS-free ITO film heater. Compared to the ITO film heater, the temperature of the PDMS/ITO film heater lasts 1.5 times longer. And the power consumption of the PDMS/ITO film heater is reduced by 35%, owing to the low thermal conductivity of the PDMS layer.

A Study on the Fabrication and Characteristics of Ceramic Heater Apparatus with High Efficiency (고효율 세라믹 발열체 제작 및 특성 시험에 관한 연구)

  • Cho, Hyun-Seob;Oh, Myoung-Kwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.3
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    • pp.1275-1278
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    • 2012
  • Compositional design and optimization of processing parameters are key factors for controlling and improving the properties of electroconductive ceramic composites. Temperature rising time of sheath heater is 1.1 times faster than SiC ceramic heater. Heating insulation of SiC ceramic heater is 2.7 times larger than sheath heater. If SiC ceramic heater is one body type of a product application, contact resistance will decrease. I think that temperature initial rising time is faster than now. The more SiC ceramic heater is used for a long time, the more economic benefit is larger in the view point of heat insulation.

Numerical Analysis on Body Temperature Change with Heating Life Vest (발열구명동의 착용에 의한 인체의 체온변화에 관한 수치해석)

  • Kim, Myoung-Jun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.3
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    • pp.241-245
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    • 2008
  • The characteristics of temperature profile around human body with heating life vest at sea were investigated in this paper. Especially, the temperature profile of human body was numerically calculated by finite difference method with Mathcad. The main parameters were seasonal mean sea water temperature, heating amount and heating duration time of heating life vest. In this paper, the boundary layer was composed by the difference matters, and the thermal conductivity was calculated with an adjacent cells using thermal resistance method. It was clarified that the body temperature was kept highly and the risk of death from hypothermia was reduced by wearing heating life vest.

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