• 제목/요약/키워드: Micro-source

검색결과 592건 처리시간 0.03초

L-band Power Enhancement through the reinsertion of backward ASE filtered by a C/L-band coupler

  • Kim Seung Taek;Gang Seong Bok;Jeong Hun;Lee Gyeong Gyun;Gang Hui Seok;Jo Yeong Jun
    • 한국광학회:학술대회논문집
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    • 한국광학회 2003년도 하계학술발표회
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    • pp.20-21
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    • 2003
  • Erbium doped fiber (EDF) sources are useful devices for characterization of optical components for wavelength division multiplexing (WDM) fiber optic communication system. Therefore, there are many efforts to extend the bandwidth and to increase the power of the light source. Especially, L-band ASE source uses the low inversion state of EDF. It makes the power efficiency very low and needs a lot of fiber as several times as the fiber needed in C-band ASE generation. (omitted)

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Study on Noise Reduction of AV Projector

  • Kim, Sang-Hoon;Bok, Ki-So;Lee, Seung-Gyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1155-1158
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    • 2007
  • To reduce acoustic noise level of an AV projector, primary noise sources of AV projector were analyzed. Based on the analyzed result, methods to control each source are presented and tried. Structure-borne noise can be controlled by anti vibration design of mounting system, and air-borne noise by reducing flow resisitvity.

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마이크로소스 인덕터 크기 결정에 관한 기초연구 (Study on Micro-Sources Modeling and optimal series inductance size)

  • 김영섭;손광명
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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    • pp.137-139
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    • 2003
  • Micro-Sources arc emerging as a providing environmentally friendly and reliable and effective solution. Micro-Source converter DC voltage of prime mover to AC voltage using voltage source inverter for interjecting with AC grid system. This paper studies optimal series inductance size for interjecting with AC grid system.

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Discimination of Decoupled Explosions from Microearthquakes

  • Kim, So-Gu
    • 한국암반공학회:학술대회논문집
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    • 한국암반공학회 1995년도 정기총회 및 학술발표회
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    • pp.108-108
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    • 1995
  • There are always some difficulties to discriminate artificial exlposions from micro-earthquakes, furthermore more difficulties to identify and determine decoupled explosions and/or multiple explosions from micro-earthquakes. In this study we use the synthetic seismogram of the in homogeneous models between the source and the observation station in order to find the source effect of the geological environment. We have found some source characteristics of the air-filled and/or water-filled cavity that we can hardly see P-n and S- waves arrivals and that the high frequency coda waves are well observed compared to the coupled explosions or earthquakes.

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최근 Micro Piezoelectric Actuator 연구 동향

  • 박준식;박효덕;강성군
    • 세라미스트
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    • 제7권3호
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    • pp.38-47
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    • 2004
  • 최근 micro structure, micro sensor, micro actuator 및 microelectronics 등을 활용하는 microelectromecha-nical systems (MEMS) 기술은 마이크로 로봇, micro manipulation, 광학 소자 및 시스템, 유체, 열, 바이오 및 화학공정 등을 위한 시스템 그리고 atomic force와 scanning tunneling microscope 등에 사용되는 다양한 소자 등 많은 잠재력을 가지고 있다. 이들 응용 분야 들은 micro actuator와 같은 mechanical power source가 요구되는 경우가 있다. 압전 특성을 포함하는 강유전체 재료는 이러한 micro actuator를 위해 여러 가지 다양한 장점을 지니고 있는데, 이들을 정리하면 다음과 같다. (중략)

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기상이동법에 의해 제조된 ZnO 결정의 형상 및 발광 특성에 미치는 TiO 첨가의 영향 (Effect of TiO Addition on Morphologies and Luminescence Properties of ZnO Crystals Fabricated by Vapor Transport Method)

  • 이근형
    • 한국재료학회지
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    • 제28권10호
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    • pp.590-594
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    • 2018
  • ZnO micro/nanocrystals are formed by a vapor transport method. Mixtures of ZnO and TiO powders are used as the source materials. The TiO powder acts as a reducing agent to reduce the ZnO to Zn and plays an important role in the formation of ZnO micro/nanocrystals. The vapor transport process is carried out in air at atmospheric pressure. When the weight ratios of TiO to ZnO in the source material are lower than 1:2, no ZnO micro/nanocrystals are formed. However, when the ratios of TiO to ZnO in the source material are greater than 1:1, the ZnO crystals with one-dimensional wire morphology are formed. In the room temperature cathodoluminescence spectra of all the products, a strong ultraviolet emission centered at 380 nm is observed. As the ratio of TiO to ZnO in the source material increases from 1:2 to 1:1, the intensity ratio of ultraviolet to visible emission increases, suggesting that the crystallinity of the ZnO crystals is improved. Only the ultraviolet emission is observed for the ZnO crystals prepared using the source material with a TiO/ZnO ratio of 2:1.

교류 펄스 전압을 이용한 평판형 대기압 유전격벽방전 플라즈마의 특성 분석 (A Study on the Dielectric Barrier Discharges Plasmas of Flat Atmospheric Pressure Using an AC Pulse Voltage)

  • 이종봉;하창승;김동현;이호준;이해준
    • 전기학회논문지
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    • 제61권5호
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    • pp.717-720
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    • 2012
  • Various types of dielectric-barrier-discharge (DBD) devices have been developed for diverse applications for the last decade. In this study, a flat non-thermal DBD micro plasma source under atmospheric pressure has been developed. The flat-panel type plasma is generated by bipolar pulse voltages, and driving gas is air. In this study, the plasma source was investigated with intensified charge coupled device (ICCD) images and Optical Emission Spectroscopy (OES). The micro discharges are generated on the crossed electrodes. For theoretical analysis, 2-dimensional fluid simulation was performed. The plasma source can be driven in air, and thus the operation cost is low and the range of application is wide.

유기 박막 트랜지스터 회로를 위한 섀도 마스크의 제작 (Fabrication of a shadow mask for OTFT circuit)

  • 이상민;박민수;이영수;이해성;주종남
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.1277-1280
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    • 2005
  • A high-aspect-ratio and high-resolution stainless steel shadow mask for organic thin-film transistors (OTFTs) circuit has been fabricated by a new method which combines photochemical machining, micro-electrical discharge machining (micro-EDM), and electrochemical etching (ECE). First, connection lines and source-drain holes are roughly machined by photochemical etching, and then the part of source and drain holes is finished by the combination of micro-EDM and ECE processes. Using this method a $100\;\mu{m}$ thick stainless steel (AISI 304) shadow mask for inverter can be fabricated with the channel length of $30\;\mu{m}\;and\;10\;\mu{m}\;respectively.\;The\;width\;of\;connection line\;is\;150\;\mu{m}$. The aspect ratio of the wall is about 5 and 15, respectively. Metal lines and source-drain electrodes of OTFTs were successfully deposited through the fabricated shadow mask.

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MLA(Micro Lens Array) 제작을 위한 광학 시뮬레이션 (The beam property simulation for the fabrication of a MLA(Micro Lens Array))

  • 오해관;서현우;김근영;위창현;송요탁;이기근;양상식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1497_1498
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    • 2009
  • This paper presents the simulation of micro-lens arrays based on dry and wet etching technique. Code V (Optical Research Associates Ltd) simulation was performed to extract optimal design parameters of a Micro-Lens Array(MLA). Thickness of UV adhesive, wavelength of laser source, curvature, and shape of lens surface were chosen for the design parameters. The simulation results showed that focal length of a MLA decreased with the increase of UV adhesive thickness. And the focal length depended on shape of lens surface and length of laser source.

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