• 제목/요약/키워드: Transfer device

검색결과 1,126건 처리시간 0.032초

입자층(粒子層)을 이용(利用)한 열교환기(熱交換器) 개발(開發)에 관(關)한 연구(硏究)(IV) -고정층(固定層) 열교환기(熱交換器)의 전열특성(傳熱特性)에 대한 실험적(實驗的) 연구(硏究) (Development of a Particle Bed Heat Exchanger (IV) -An Experimental Study on Heat Transfer Characteristics of Fixed Bed Heat Exchanger)

  • 양한주;서정윤
    • 설비공학논문집
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    • 제2권3호
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    • pp.234-242
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    • 1990
  • In this study, heat transfer characteristics of vertical fixed bed with air flowing through were experimentally investigated. The experiments were conducted for cases where heat was transfer steady state conditions from an immersed cylindrical heated to the surrounding fixed ved of steel balls. Based on the experimental data, the optimum conditions for heat transfer augmentation have been determined and shows in empirical forms. For the same power loss, comparison of heat transfer effect between the fixed bed and single phase forced convection device indicates that both miniaturization of heat exchange device and heat transfer augmentation at low flow velocity are possible by application of the fixed bed to heat exchangers. The present results could provide a useful design information for the heat exchangers where fixed beds are used.

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PCI 2.2에서 프리페치 요구를 이용해서 데이터 전송 효율을 향상시키는 효과적인 방법 (Method to improve the Data Transfer Efficiency in the PCI 2.2 using Prefetch Request)

  • 현유진;성광수
    • 전자공학회논문지CI
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    • 제41권4호
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    • pp.1-8
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    • 2004
  • PCI 2.2 버스 마스터가 메모리 읽기 명령으로 타겟 장치에 데이터 전송을 요구하면 타겟 장치는 내부적으로 데이터 준비하는데 시간이 필요하므로 데이터 전송 없이 장시간 PCI 버스를 점유하는 상황이 발생할 수 있다. 이는 PCI 버스 사용 효율 및 데이터 전송 효율을 떨어뜨리게 되며 이를 해결하기 위해 PCI 2.2에서는 지연 트랜잭션 메커니즘을 이용한다. 그러나 이 방법은 타겟 장치가 프리페치해야 할 정확한 데이터의 양을 알 수 없기 때문에 데이터 전송 효율이 떨어진다. 본 논문에서는 메모리 읽기 명령을 수행하고자 하는 버스 마스터가 메모리 쓰기 명령어를 이용하여 타겟 장치에게 읽어올 데이터의 양을 미리 알려주는 프리페치 요구를 이용해 보다 효율적으로 데이터를 전송하는 방법을 제안한다. 모의실험 결과 제안된 방법이 지연 트랜잭션에 비해 데이터 전송 효율이 평균 10 % 향상되었다.

무선 전력전송을 위한 초음파 트랜스듀서 시스템 개발 Part 1: 송신소자 개발 (Development of ultrasonic transducer system for wireless power transfer Part 1: Transmitter development)

  • 염우섭;황건;이성규
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 춘계학술대회 논문집
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    • pp.771-776
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    • 2012
  • Recently, wireless power transfer technology is ready to be commercialized in consumer electronics. It draws attention of not only experts but also public because of its convenience and huge market. However, previous technologies such as magnetic resonance and induction coupling have limited applications because of its short transfer distance compared to device size and magnetic intensity limitation for the safety of body exposure. As an alternative, ultrasonic wireless power transfer technology is proposed. The ultrasonic wireless power transfer system is composed of transmitter which converts electrical energy to ultrasonic energy and receiver which converts the ultrasonic energy to the electrical energy again. This paper is focused on the development of high energy conversion efficiency of ultrasonic transmitter. Optimal transfer frequency is calculated based on the acoustic radiation and damping effect. The transmitter is designed through numerical analysis, and is manufactured to match the optimal transfer frequency with the size of 100mm diameter, 12.2 mm thickness plate. The energy conversion efficiency of about 13.6% at 2m distance is obtained, experimentally. This result is quite high considered with the device size and the power transfer distance.

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다구찌 법을 이용한 전력전환차단기의 설계 (Design of an power transfer breaker by Taguchi method)

  • 김경선;김권희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집A
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    • pp.810-814
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    • 2001
  • power transfer breaker is a device used to transfer the load from the electricity power line to the emergency generators. In case of overload, it also functions as a circuit breaker. In this work, a new mechanism for the device is suggested. Among the various design challenges, optimization of the trigger mechanism is identified as of central importance. Optimal design decisions are made with the use of Taguchi method.

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Effects of Morphology on Energy transfer and Device performance in Phosphorescent Dye Doped Polymer Light Emitting Devices

  • Noh, Yong-Young;Lee, Chang-Lyoul;Kim, Jang-Joo;Yase, Kiyoshi
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.98-101
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    • 2002
  • The effect of morphology on energy transfer and device performance in phosphorescent dye doped polymer light emitting diodes is reported. We selected two host polymers (PVK and PFHP) which have nearly the same potential for the energy transfer to Ir(ppy)$_3$. The PFHP:Ir(ppy)$_3$ film showed b-micron size aggregation, whereas the PVK:Ir(ppy)$_3$ film showed homogeneous and smooth images. As a result, energy transfer is efficient with high emission efficiency in PVK:Ir(ppy)$_3$ whereas little energy transfer and low quantum efficiency are obtained in PFHP:Ir(ppy)$_3$.

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A study on BSN data collection technique through mobile devices in a cloud environment

  • Hwang, Chigon;Kim, Hyung-Seok;Lee, Jong-Yong;Jung, Kyedong
    • International journal of advanced smart convergence
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    • 제6권2호
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    • pp.82-88
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    • 2017
  • The data generated by the BSN sensor attached to the human body is mostly mobile. Accordingly, in a mobile cloud environment that processes BSN data, the service should not be fixed in a specific area but be able to support it according to the move. The mobile device must be able to process, filter and transmit the collected BSN data. The cloud server must be able to collect the data processed by the mobile device and provide it as a service. And the transfer of data requires standardized transfer between each device. In this paper, we propose a data delivery method through standard schema when mobile device processes data and provides service in cloud system and a data processing method according to the movement of the mobile device.

유기박막의 누적형태에 따른 전기특성 (Electrical Properties of Organic Thin Films by Deposition Type)

  • 송진원;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.287-290
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    • 2000
  • We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 20[mN/m]. LB layers of Arac. acid deposited by LB method were deposited onto y-type silicon wafer as x, y, z-type film. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/arachidic acid/Al, the number of accumulated layers. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V].

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전자 장비 냉각에 있어서의 분리형 써모사이펀의 적용 (The application of separate type thermosyphon for cooling of electronic equipments)

  • 김지훈;박신보;윤정호;김시범;전철호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.725-728
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    • 2002
  • A separate type thermosyphon can be utilized as a cooling device of electronic equipments (such as CPU of a personal computer or notebook). This study was carried out to investigate the cooling effect of separate type thermosyphon and to find the adequate parameters affecting the separate type thermosyphon. The heat transfer characteristics of separate type thermosyphon were obtained from experimental results. A $50{\times}50{\times}2 mm$ heat source was copied after CPU for the experiments. The results indicate that the device is capable of dissipating 60W of thermal energy and keeping the heat plate surface temperature under 50'E and the device can transfer heat from the evaporator to the condenser through natural circulation (without any external driving forces). Some transport phenomena of the working fluid and the heat transfer characteristics of the loop were observed in the experiments and are discussed in detail below.

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In-vitro 유동장에서 진동형 폐 보조장치를 이용한 산소전달 효율의 향상 (Enhancement of Oxygen Transfer Efficiency Using Vibrating lung Assist Device in In-Vitro Fluid Flow)

  • 권대규;김기범;이삼철;정경락;이성철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1332-1335
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    • 2003
  • This paper presents the enhancement of oxygen transfer efficiency using the vibrating intravascular lung assist device (VIVLAD) in in-vitro experiments for patients having chronic respiratory problems. The test section was a cylinder duct with the inner diameter of 30 mm. The flow rate was controlled by the pump and monitored by a built-in flow meter. The vibration apparatus was composed of a piezo-vibrator, a function generator. and a power amplifier. The direction of vibration was radial to the fluid flow. Gas flow rates of up to 6 l/min through the 120-cm-Jong hollow fibers have been achieved by exciting a piezo-vibrator. The output of PVDF sensor were investigated by various frequencies in VIVLAD. The experimental results showed that VIVLAD would be enhance oxygen transfer efficiency.

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Electrical Bistable Characteristics of Organic Charge Transfer Complex for Memory Device Applications

  • Lee, Chang-Lyoul
    • Applied Science and Convergence Technology
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    • 제24권6호
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    • pp.278-283
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    • 2015
  • In this work, the electrical bistability of an organic CT complex is demonstrated and the possible switching mechanism is proposed. 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tetracyanoquinodimethane (TCNQ) are used as an organic donor and acceptor, respectively, and poly-methamethylacrylate (PMMA) is used as a polymeric matrix for spin-coating. A device with the Al/($Al_2O_3$)/PMMA:BCP:TCNQ[1:1:0.5 wt%]/Al configuration demonstrated bistable and switching characteristics similar to Ovshinsky switching with a low threshold voltage and a high ON/OFF ratio. An analysis of the current-voltage curves of the device suggested that electrical switching took place due to the charge transfer mechanism.