• Title/Summary/Keyword: PM Skew

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Design, Fabricaiton and Testing of a Piezoresistive Cantilever-Beam Microaccelerometer for Automotive Airbag Applications (에어백용 압저항형 외팔보 미소 가속도계의 설계, 제작 및 시험)

  • Ko, Jong-Soo;Cho, Young-Ho;Kwak, Byung-Man;Park, Kwan-Hum
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.2
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    • pp.408-413
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    • 1996
  • A self-diagnostic, air-damped, piezoresitive, cantilever-beam microaccelerometer has been designed, fabricated and tested for applications to automotive electronic airbag systems. A skew-symmetric proof-mass has been designed for self-diagnostic capability and zero transverse sensitivity. Two kinds of multi-step anisotropic etching processes are developed for beam thickness control and fillet-rounding formation, UV-curing paste has been used for sillicon-to-glass bounding. The resonant frequency of 2.07kHz has been measured from the fabricated devices. The sensitivity of 195 $\mu{V}$/g is obtained with a nonlinearity of 4% over $\pm$50g ranges. Flat amplitude response and frequency-proportional phase response have been obserbed, It is shown that the design and fabricaiton methods developed in the present study yield a simple, practical and effective mean for improving the performance, reliability as well as the reproducibility of the accelerometers.

Effects of $C_2F_{6}$ Gas on Via Etching Characteristics ($C_2F_{6}$ 가스가 Via Etching 특성에 미치는 영향)

  • Ryu, Ji-Hyeong;Park, Jae-Don;Yun, Gi-Wan
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.1
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    • pp.31-38
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    • 2002
  • In order to improve the 0.35 $mutextrm{m}$-via hole etching process the etching characteristic of the gas $C_2F_{6}$ has been analyzed. The samples were triple-layer films(TEOS/SOG/TEOS) on 8-inch wafers and the orthogonal array matrix technique was used for the process. The equipment for etching was the transformer coupled plasma (TCP) source which is a type of high density plasma(HDP). This experiment showed the etching rate for $C_2F_{6}$ was 0.8 $mutextrm{m}$/min-1.1 $mutextrm{m}$/min and the measured uniformity was under $pm$6.9% in the matrix window. The CD skew comparison between pre and post-etching was under 10% which is an outstanding results in the window of profile in anisotropic etching. There was no problem in C2F6 with the flow rate of 20sccm, but when 14sccm of $C_2F_{6}$ was supplied there was a recess problem on the inner wall of SOG film. Consequently the etching characteristic of $C_2F_{6}$ shows a fast etching rate and a very wide process window in HDP TCP.

Experimental Verifications and Electromagnetic Characteristics Analysis of Multi-Pole Permanent Magnet Generator for Small-Scaled Wind Power System (소용량 풍력시스템을 위한 다극 영구자석형 발전기의 전자기적 특성 해석 및 실험적 검증)

  • Jang, Seok-Myeong;Ko, Kyoung-Jin;Kim, Hyun-Kyu;Choi, Jang-Young;Yoon, Gi-Gap
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.609_610
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    • 2009
  • This paper deals with experimental verifications and the electromagnetic characteristics analysis of multi-pole permanent magnet (PM) generator for small-scaled wind power system. Field distribution due to PMs and winding current, cogging torque considering skew effect are analyzed. In addition, using the equivalent circuit method and dynamic d-q method, generating performance analysis is performed. Analysis results are validated by comparison with nonlinear finite element analyses and experimental results.

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A Skew Correction for Document Images by the Extraction of Blank Lines (공백행 추출에 의한 기울어진 문서 영상의 보정)

  • 정재영;김문현
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10c
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    • pp.541-543
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    • 1998
  • 본 논문에서는 선형적으로 기울어진 문서 영상의 기울기를 검출하기 위한 단순하면서도 효과적인 알고리즘을 제안한다. 문서 내의 인접한 두 행 사이에는 일정한 두께의 공백 행이 존재하며, 그 공백 행의 기울기는 실제 문서의 기울어진 정도를 반영한다는 사실에 기인한다. 먼저, 간단한 모폴로지 연산을 이용하여 문자행 영역과 공백행 영역을 분리한 후, 이를 일정 간격으로 수직 샘플링하여 수직선 상에 있는 모든 공백행의 중심점(행간점)을 찾는다. 전체 영상으로부터 동일한 공백 행상에 있는 임의의 두 행간점간에 계산된 기울기들의 분포를 보면 실제 문서의 기울기에서 최대 값을 가진다. 제안한 알고리즘을 다양한 형태의 가로쓰기 문서(검출 가능한 최대 기울기 : $\pm$45$^{\circ}$)에 적용하여 0.5$^{\circ}$의 오차범위 내에서 정확한 결과를 얻을 수 있음을 보인다.

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Minimization of Cogging Force in a Stationary Discontinuous Armature Linear Permanent Magnet Motor at the Outlet Edge

  • Kim, Yong-Jae;Jung, Sang-Yong
    • Journal of Magnetics
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    • v.16 no.3
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    • pp.288-293
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    • 2011
  • Generally, the discontinuous armature permanent magnet linear synchronous motor (PM-LSM) is composed by the stator block (accelerator, re-accelerator, and decelerator) and the free running section. However, the stationary discontinuous armature design involves the velocity variation of the mover during drive when the armature's non-installation part changes over to installation part as a result of the outlet edge of the armature. Therefore, we considered deforming the shape of the outlet edge at the armature and apply skew on the permanent magnet by displacing the two magnet segments of each pole. This paper presents the results of a three-dimensional (3-D) numerical analysis with a finite element method (FEM) of the force exerted by the outlet edge.

Development of Polarization-Controllable Active Phased Array Antenna for Receiving Satellite Broadcasting (편파가변 위성 방송 수신용 능동 위상 배열 안테나 개발)

  • Choi, Jin-Young;Lee, Ho-Seon;Kong, Tong-Ook;Chun, Jong-Hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.29 no.5
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    • pp.325-335
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    • 2018
  • We herein present a study on the active phased array antenna for receiving satellite broadcasting that can electrically align its polarization to that of target transmitters in its moving condition or in the Skew angle arrangement of the broadcasting satellite receiver. Hence, we have developed an active phased array structure composed of the self-developed Vivaldi antenna and multifunction core (MFC) chip, receiving RF front end module, and control units. In particular, the new Vivaldi antenna designed in the Ku-band of 10.7 - 14.5 GHz to receive one desired polarization mode such as the horizontal or vertical by means of an MFC chip and other control units that can control the amplitude and phase of each antenna element. The test results verified that cross-polarization property is 20 dB or higher and the primary beam can be scanned clearly at approximately ${\pm}60^{\circ}$.