• 제목/요약/키워드: In-direct Heater

검색결과 30건 처리시간 0.026초

Glow-Plug를 이용한 가솔린 연료의 조기증발 특성 실험 연구 (The Experimental Study of Early Fuel Evaporation Characteristics Gasoline Engine Using Glow-Plug)

  • 문영호;김진구;오영택
    • 한국자동차공학회논문집
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    • 제9권2호
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    • pp.1-10
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    • 2001
  • In order to reduce hydrocarbon emissions of spark ignition engine, it is important not only to improve catalyst conversion efficiency but also to reduce direct engine out hydrocarbon emissions, during cold starting and warm up process. Tjerefore many researchers have been attracted to develop an early fuel evaporator (EFE) by introducing a ceramic heater for a solution of engine out hydrocarbon emissions in SI engine. But, the performance of the EFE in MPI engine to reduce the exhaust emissions and to improve the cold startability has nat been clarified yet. The purpose of this study is to evaluate the feasibility of a glow plug for EFE.

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전립선 전용 전자쑥뜸 발열단자의 개발 (Development of the Special Heat Generating Terminal of Cauterizer for Prostate)

  • 조봉관;이윤호
    • Journal of Acupuncture Research
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    • 제26권2호
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    • pp.41-48
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    • 2009
  • Objectives : The conventional direct and indirect moxibustion therapies for prostate treatment could not been applied to the acupuncture point of $CV_1$(Conception Vessel Meridian 1, 會陰) because of its boring body region. The position of $CV_1$(會陰) is the back side of hard part between the anus and the genital organ. The conventional moxibustion methods have many troubles in operating to the acupuncture point of $CV_1$(會陰). In order to get rid of these problems, we have suggested the special heat generating terminal especially for prostate. The features of the special heat generating terminal for prostate are the low temperature infrared heater and the adhesive moxa-pad. These features are no burnt, no fiery and especially suitable for the point of $CV_1$(會陰). Methods: The heat generating terminal which is a part of the moxa-extract moxibustion cauterizer is composed of a PTC(Positive Temperature Coefficients) ceramic heater and the adhesive moxa-pad We had got the experimental demonstrations by the stimulating the acupuncture points which are $CV_1$(會陰), $BL_{28}$(Bladder Meridian 28, 膀胱兪), and $CV_3$(Conception Vessel Meridian 3, 中極) with the special heat generating terminal for the prostatitis and the benign prosthetic hypertrophy. And the stimulation level was 43$^{\circ}C$ infrared heat for one hour. The type of thermography is IRIS-5000. Results : With one subject suffering the prostatitis and another subject suffering the benign prosthetic hypertrophy, we cauterized the acupuncture points $CV_1$(會陰), $BL_{28}$(膀胱兪) and $CV_3$(中極) with the special heat generating terminal for prostate. We measured the temperature variations by the thermography before and after stimulations. Finally we estimated the tendency of temperature decreasing in the region of post-stroke urinary symptoms and the improvement of nocturnal enuresis after the stimulations. Conclusions : We suggest that the special heat generating terminal of moxa-extract moxibustion cauterizer proposed herein is effective for the treatment of prostate by NIH-CPSI and IPSS.

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히트펌프를 이용한 PEMFC 기반 열병합 발전 시스템 (PEMFC Based Cogeneration System Using Heat Pump)

  • 뚜안앵;김영상;이동근;안국영
    • 한국수소및신에너지학회논문집
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    • 제32권5호
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    • pp.324-330
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    • 2021
  • In recent years, polymer electrolyte membrane fuel cell (PEMFC) based cogeneration system has received more and more attention from energy researchers because beside electricity, the system also meets the residential thermal demand. However, the low-quality heat exited from PEMFC should be increased temperature before direct use or storage. This study proposes a method to utilize the heat exhausted from a 10 kW PEMFC by coupling a heat pump. Two different configuration using heat pump and a reference layout with heater are analyzed in term of thermal and total efficiency. The system coefficient of performance (COP) increases from 0.87 in layout with heaters to 1.26 and 1.29 in configuration with heat pump and cascade heat pump, respectively. Lastly, based on system performance result, another study in economics point of view is proposed.

뜸의 특성 연구 방법론에 대한 문헌고찰 (Literature Review on Research Methodology Assessing Properties of Moxibustion)

  • 임진웅;이상훈
    • Journal of Acupuncture Research
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    • 제29권6호
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    • pp.1-10
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    • 2012
  • Objectives : The aim of this review was to summarize and assess researches reporting thermal properties of moxibustion. Methods and Materials : We searched one electronic database(PubMed) and two journals(The Journal of Korean Medicine and The Journal of Korean Acupuncture & Moxibustion Society) and for the articles published until Nov. 2012. The articles reporting thermal characteristic of moxibustion were selected and reviewed. 31 articles were included and assessed in this review. The type of moxibustion, the material beneath moxbustion, main outcome and the amount of information were reviewed. The amount of information was defined as 1 for one main outcome reported in each article. Results : Direct moxibustion were used in 15 articles and indirect moxibustion were used in 19 articles. 11 researches used anti-heating plate for the material beneath moxibustion, one article used steel ring, agar with anti-heating plate, six articles used skin and another six articles used heater. Two articles used animals and another two articles used metals. The mean value of the amount of information was $4.41{\pm}2.94$(SD). Conclusions : Research articles assessing properties of moxibustion have been consistently published since 1993, and employed various methodologies. The amount of information has been associated with four section analysis and is currently decreasing. Research assessing properties of moxibustion with clinical effectiveness is needed.

YBCO - film production by thermal co-evaporation for microwave and electrical power applications

  • Prusseit, W.;Semerad, R.
    • 한국초전도학회:학술대회논문집
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    • 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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    • pp.145-145
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    • 2000
  • Large area YBCO - films are series produced by thermal co-evaporation using a deposition scheme known as Garching process, which allows intermittent oxygen supply in a high vacuum ambient by an oxygen cup spaced closely underneath the moving substrates. The deposition area of 9" diameter is capable to handle very large wafers up to 8" diam. or numerous smaller wafers. The large distance between substrates and boat sources and an elaborate heater design guarantee excellent film uniformity over the entire deposition area. YBCO - films deposited by this technique are commercially fabricated for a variety of applications - the most prominent are resistive fault current limiters and microwave filters for mobile or satellite communications. IMUX and OMUX - filters are currently space qualined by Robert Bosch GmbH and are expected to be launched and installed on an experimental platform of the international space station ALPHA in 2001. Both of the above applications require quite different film specifications on the one hand, but at the same time extremely high uniformity and reproducibility on the other hand, since hundreds of YBCO - films are combined to large systems or have to be approved for manned space missions. The success of such projects is direct evidence that the technique of thermal evaporation is readily capable to meet these high demands and has become the major deposition technique to support the emerging HTS market.

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전기차용 고전압 케이블의 화재 위험성에 관한 연구 (A Study on the Fire Risk of High-voltage Cables for Electrical Vehicles)

  • 강신동;박예진;김시현;김재호
    • 한국안전학회지
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    • 제38권4호
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    • pp.8-14
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    • 2023
  • This study presents the characteristics of short circuits (SCs) caused by excessive currents in high-voltage cables used in electric vehicles and emphasizes the need to calculate the cross-sectional areas of these cables according to the SC current. Three direct current power supplies were connected in parallel to test the SC characteristics caused by excessive currents, and a timer and a magnetic contactor were used to deliver the conduction time and SC current. A circular infrared-radiation heater was used to test the temperature-dependent SC characteristics, a thermocouple was used to measure the temperature, and a shunt resistor was used to measure the current. As the SC current increased, the fusing time of the cable decreased. Additionally, a high-voltage cable (with an area of 16 mm2 ) used in electric vehicles fused when a current (approximately equal to 55 times the allowable current) flowed for 0.2 s (operating time of the protective device). When the SC current is 10 kA, the cable may fuse during the operating time of the protective device, thus creating a fire hazard. In electric vehicles, the size of the SC current increases in proportion to the capacity of the battery. Thus, the cross-sectional areas of the cables used should be calculated accordingly, and cable operations should be properly coordinated with the surrounding protective devices.

Si-Containing Nanostructures for Energy-Storage, Sub-10 nm Lithography, and Nonvolatile Memory Applications

  • 정연식
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.108-109
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    • 2012
  • This talk will begin with the demonstration of facile synthesis of silicon nanostructures using the magnesiothermic reduction on silica nanostructures prepared via self-assembly, which will be followed by the characterization results of their performance for energy storage. This talk will also report the fabrication and characterization of highly porous, stretchable, and conductive polymer nanocomposites embedded with carbon nanotubes (CNTs) for application in flexible lithium-ion batteries. It will be presented that the porous CNT-embedded PDMS nanocomposites are capable of good electrochemical performance with mechanical flexibility, suggesting these nanocomposites could be outstanding anode candidates for use in flexible lithium-ion batteries. Directed self-assembly (DSA) of block copolymers (BCPs) can generate uniform and periodic patterns within guiding templates, and has been one of the promising nanofabrication methodologies for resolving the resolution limit of optical lithography. BCP self-assembly processing is scalable and of low cost, and is well-suited for integration with existing semiconductor manufacturing techniques. This talk will introduce recent research results (of my research group) on the self-assembly of Si-containing block copolymers for the achievement of sub-10 nm resolution, fast pattern generation, transfer-printing capability onto nonplanar substrates, and device applications for nonvolatile memories. An extraordinarily facile nanofabrication approach that enables sub-10 nm resolutions through the synergic combination of nanotransfer printing (nTP) and DSA of block copolymers is also introduced. This simple printing method can be applied on oxides, metals, polymers, and non-planar substrates without pretreatments. This talk will also report the direct formation of ordered memristor nanostructures on metal and graphene electrodes by the self-assembly of Si-containing BCPs. This approach offers a practical pathway to fabricate high-density resistive memory devices without using high-cost lithography and pattern-transfer processes. Finally, this talk will present a novel approach that can relieve the power consumption issue of phase-change memories by incorporating a thin $SiO_x$ layer formed by BCP self-assembly, which locally blocks the contact between a heater electrode and a phase-change material and reduces the phase-change volume. The writing current decreases by 5 times (corresponding to a power reduction of 1/20) as the occupying area fraction of $SiO_x$ nanostructures varies.

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흡광 액체의 펄스 레이저 가열에 의해 생성된 기포 거동의 실험적 해석 (Experimental Analysis of Bubble Dynamics Induced by Pulsed-Laser Heating of Absorbing Liquid)

  • 장덕석;홍종간;좌성훈;김동식
    • 대한기계학회논문집B
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    • 제30권5호
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    • pp.413-421
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    • 2006
  • The bubble dynamics induced by direct laser heating is experimentally analyzed as a first step to assess the technical feasibility of laser-based ink-jet technology. To understand the interaction between laser light and ink, the absorption spectrum is measured for various ink colors and concentrations. The hydrodynamics of laser-generated bubbles is examined by the laser-flash photography. When an Ar ion laser pulse (wavelength 488 nm) with an output power up to 600 mW is incident on the ink solution through a transparent window, a hemispherical bubble with a diameter up to ${\sim}100{\mu}m$ can be formed with a lifetime in a few tens of microsecond depending on the laser power and the focal-spot size. Parametric study has been performed to reveal the effect of laser pulse width, output power, ink concentration, and color on the bubble dynamics. The results show that the bubble generated by a laser pulse is largely similar to that produced by a thin-film heater. Consequently, the present work demonstrates the feasibility of developing a laser-actuated droplet generation mechanism for applications in ink-jet print heads. Furthermore, the results of this work indicate that the droplet generation frequency is likely to be further increased by optimizing the process parameters.

외부공기 유입방식에 따른 느타리버섯 생육실의 온도변화 및 자실체의 생육특성 (Heating and cooling properties in cultivation room and cultural characteristics of oyster mushroom according to type of air exchange)

  • 장명준;이윤혜;주영철
    • 한국버섯학회지
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    • 제11권4호
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    • pp.214-218
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    • 2013
  • 외부공기 유입방식에 따른 느타리버섯의 생육특성을 조사하기 위하여 3가지 처리구를 두어 실험한 결과 모든 처리구에서 재배기간 중 온도편차가 발생하였고, 처리구 모두 1, 2, 8월에 가장 높았으며, T2(열교환기)와 T3(기밀실)에서 T1(외부공기 직접유입) 보다 온도편차가 작은 경향이었다. 재배기간 중 냉방시간은 T1(외부공기 직접유입)은 1,090.3시간, T2(열교환기)는 661.1시간, T3(기밀실)은 865.0시간이었고, 평균 냉방절감율은 T1(외부공기 직접유입) 대비 T2(열교환기)는 21%, T3(기밀실)은 11%이었다. 재배기간 동안 난방기의 년중 가동시간은 T1(외부공기 직접유입)은 1,506.9시간, T2(열교환기)는 875.6시간, T3(기밀실)은 1,054.2시간으로 T2의 가동시간이 가장 작았고, 년중 평균 난방절감율은 T1(외부공기 직접유입) 대비 T2(열교환기)는 22%, T3(기밀실)은 16%이었다. 외부공기 유입방식에 따른 냉방정도(CD-H)는 T1(외부공기 직접유입)>T3(기밀실)>T2(열교환기)의 순이었고, 난방정도(HD-H)도 냉방정도(CD-H)의 경우와 동일하였다. 수량은 T2(열교환기)와 T3(기밀실)에서 T1(외부공기 직접유입) 보다 4, 9, 10월을 제외한 전 기간에서 높았다. 이와 같은 결과로 시설재배사에서 느타리버섯 병재배시 열교환기 또는 기밀실을 설치하여 재배할 경우 에너지를 절감할 수 있고, 수량 및 고품질의 느타리버섯을 수확할 수 있어 농가소득증대에 기여할 것으로 판단되었다.

온침의 온도변화 특성에 대한 문헌 고찰 연구 (A Review on the Characteristics of Temperature Variation in Warm Needle)

  • 이주현;조효림;김선혜;이연선;박세원;문소리;정찬영;성원석;조현석;김경호;이병욱;김은정
    • 대한한의학회지
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    • 제40권3호
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    • pp.112-138
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    • 2019
  • Objectives: The purpose of this study is to organize the research methods and results of studies related to the temperature of the warm needle for systematic utilization of warm needling technique. Methods: This study used the databases of nine (Pubmed, Science Direct, Cochrane Central, 4 Korean databases, CNKI, CiNii) to analyze temperature-related studies of the warm needle from 2000 to June 2019. Results: A total of 19 papers were included. Of these, 15 were used for mugwort, 2 for high frequency, and 1 for both mugwort and high frequency, and the other one for a ceramic heater. The maximum temperature rises as the amount of moxibustion increases. It is also affected by the density of moxa and the ignition part. There were 16 papers using stainless steel needles and 4 papers using a needle made of gold or silver to compare. In the area of the needle, the closer it is to moxibustion, the hotter it is. Compared to stainless steel needles, gold and silver needles showed almost twice the temperature. The effects of environment and radiant heat should be considered during warm needle procedures. Conclusions: There are various experimental methods such as warm needle technique materials, methods, measuring parts, measuring instruments, etc. The results were also very diverse. When setting the heating source, ignition part, size of moxibustion, etc. of warm needles, it should be implemented in a way that takes safety and validity into account. Considerations for temperature characteristics, radiant heat, etc. of warm needles will be needed when making warm needle apparatus.