• 제목/요약/키워드: switches

검색결과 1,791건 처리시간 0.033초

순차적으로 전압 인가된 RF MEMS스위치를 이용한 재구성 슬롯 안테나의 설계 (Design of a Reconfigurable Slot Antenna using Sequentially Voltage-Applied RF MEMS Switches)

  • 심준환;윤동식;박동국;강인호
    • 한국항해항만학회지
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    • 제28권5호
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    • pp.429-434
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    • 2004
  • 본 논문은 순차적으로 전압 인가된 RF MEMS 스위치를 이용하여 재구성 슬롯 안테나를 설계하였다. MEMS 스위치의 구동전압은 하부 전극과 상부 스위치 사이의 에어캡 높이에 따른 스위치의 특성을 ANSYS 시뮬레이션으로 분석하였다. MEMS 스위치의 구동전압은 하부전극과 상부 스위치 사이의 에어캡 높이와 스위치 형상에 의해 결정된다. 설계된 MEMS 스위치의 길이는 각각 240$\mu\textrm{m}$, 320 $\mu\textrm{m}$, 400 $\mu\textrm{m}$ 이고, 에어캡은 6$\mu\textrm{m}$이었다. 설계된 슬롯 안테나는 전체크기가 10 mm x 10 mm이며, 슬롯의 크기는 길이가 500 $\mu\textrm{m}$, 폭이 200 $\mu\textrm{m}$이었다. 그리고 CPW 급전선은 전체의 길이는 5 mm이며, 입구에서의 CPW는 30-80-30 $\mu\textrm{m}$이괴, 슬롯에서의 CPW는 150-300-150 $\mu\textrm{m}$이다. 세안된 소사의 공진주파수의 튜닝은 RF MEMS 스위치에 DC 바이어스를 인가함으로서 안테나의 전기적인 길이를 변화시켜 이루어진다. 설계된 슬롯 안테나를 시뮬레이션, 제조 및 측정을 하였다.

준 공유 출력 버퍼형 스위치 구조 (Quasi-Shared Output Buffered Switch)

  • 남승엽;성단근;안윤영
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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    • pp.283-286
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    • 2000
  • One major drawback of conventional output buffered switches is that the speed of writing cells into output buffer should be N times faster than input link speed. This paper proposes a new output buffer switch that divides one output buffer into several buffers and virtually shares the divided buffers by using a distributor. The proposed switch makes it possible to reduce the memory speed. The proposed switch is evaluated in terms of the average cell latency compared with the input buffered switches which use the arbitration alogorithms, i.e., iSLIP or wrapped wave front arbiter(WWFA).

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AC-PDP Sustain Driver using Bidirectional Switches

  • Kang, Feel-Soon
    • Journal of Electrical Engineering and Technology
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    • 제6권1호
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    • pp.86-93
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    • 2011
  • To minimize the cost and power consumption of PDP TV, a practical sustain circuit topology is presented with an address-and-display-period-separated driving scheme. The proposed sustain driver employs bidirectional switches to reduce the number of components. Operational principles and corresponding features are illustrated and compared with the conventional approach. The valuable contributions of the proposed high-performing sustainer has been proven by computer-aided simulations and experiments by using a prototype equipped with 7.5-inch diagonal panel operated at 200 kHz switching frequency.

A RELATIONSHIP BETWEEN VERTICES AND QUASI-ISOMORPHISMS FOR A CLASS OF BRACKET GROUPS

  • Yom, Peter Dong-Jun
    • 대한수학회지
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    • 제44권6호
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    • pp.1197-1211
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    • 2007
  • In this article, we characterize the quasi-isomorphism classes of bracket groups in terms of vertices using vertex-switches. In particular, if two bracket groups are quasi-isomorphic, then there is a sequence of vertex-switches transforming a collection of vertices of a group to a collection of vertices of the other group.

전력용반도체 소자를 이용한 새로운 고전압 펄스발생회로 (High Voltage Pulse Generator using Power Semiconductor Switches)

  • 이영운
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2000년도 전력전자학술대회 논문집
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    • pp.30-33
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    • 2000
  • Using power semiconductor switches such as IGBTs diodes and L-C circuits novel repetitive impulse voltage generator is developed. In the presented circuits high voltage pulse is generated by series-connection of capacitors and IGBTs. The charging of capacitors and voltage balance of IGBTs is done automatically. To verify the proposed circuit 20kV, 300A pulse generator is manufactured and tested.

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The p-Hydroxyphenacyl Photoremovable Protecting Group

  • Richard S. Givens;Lee, Jong-Ill
    • Journal of Photoscience
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    • 제10권1호
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    • pp.37-48
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    • 2003
  • A review of the background and development of the p-hydroxyphenacyl group (pHP) as a photoprotecting group for biological substrates is chronicled. The pHP group has promise as an efficient, rapid phototrigger for the study of very fast biological processes. Applications include the release of neurotransmittors and second messengers, enzyme switches and nucleotides.

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Novel energy recovery circuit using an address voltage source

  • Yi, Kang-Hyun;Moon, Gun-Woo
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2008년도 하계학술대회 논문집
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    • pp.416-418
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    • 2008
  • Cost effective and high efficiency energy recovery circuit (ERC) using an address voltage source is proposed. Different from prior ERC, the proposed circuit uses a voltage source to charge a panel and a current source to discharge the panel. As a result, it can be achieved zero voltage switching (ZVS) of switches in H-bridge inverter and zero current switching (ZCS) of switches of the ERC. Moreover, the proposed ERC can obtain high efficiency, high performance and the decrease of the cost and the size.

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소프트 스위칭방식의 보조스위치를 갖는 새로운 ZCS-PWM 컨버터 (New Zero-Current-Switching PWM Converters with Soft-Switching Auxiliary Switch)

  • 마근수;김양모
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.1002-1004
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    • 2001
  • In conventional zero-current-switching(ZCS) PWM converters, the switching loss, stress and noise can't be minimized because they adopt auxiliary switches operated in hard-switching. In this paper, new ZCS-PWM converters of which auxiliary switches always operate with soft-switching are proposed. Therefore, the proposed ZCS-PWM converters are most suitable for systems requiring high-power density. The characteristics of these converters are verified by experimental results.

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간단한 보조회로를 이용한 새로운 IGBT 직렬 구동 기법에 관한 연구 (The study on novel method of IGBTs series connection using simple auxiliary circuit)

  • 백주원;류명효;김성철;이영식;유동욱;김흥근
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1999년도 전력전자학술대회 논문집
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    • pp.206-209
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    • 1999
  • There exists an acute need for high voltage solid-state-switches in a broad area of applications. With the proposed method using simple voltage balancing circuit with series connected IGBTs, it is realized high voltage semiconductor switches with working voltages of several order kilo-volts. The operation principle of the proposed circuit is explained and analyzed. Transient and static voltage-balancing is tested on a experimenta 3kV/45A switch with four series-connected IGBTs.

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다기능개폐기를 이용한 선로운전자동화 (The feeder automation using the switches with multi functions)

  • 송병권;홍순학;하복남
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 A
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    • pp.183-186
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    • 1992
  • The distribution automation functions include feeder automation, data acquisition and processing, remote meter reading and load management. This report explains the function of feeder automation and the accomplishment method of feeder automation using the switches of distribution system with multi functions.

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