• 제목/요약/키워드: Planar.

검색결과 3,651건 처리시간 0.031초

불균일 트랜스듀서 감도를 갖는 평면 배열의 빔 설계 기법 (A Beam Design Method for Planar Array with Unequal Transducer Sensitivities)

  • 조치영;권오조
    • 소음진동
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    • 제8권4호
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    • pp.663-669
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    • 1998
  • In this paper, a beam design method is presented for the planar array with unequal transducer sensitivities. Basically the proposed method consists of two steps. At first, the optimum weightings are designed with the assumption that all array elements have an uniform sensitivity. Next, the compesnated weightings for the unequal transducer sensitivities can reversely be determined from an inverse problem utilizing the design beam pattern evaluated by the predetermined optimal weightings. A numerical example is inculded to illustrate the proposed method.

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Silica-Based Planar Lightwave Circuits for WDM Applications

  • Okamoto, Katsunari;Inoue, Yasuyuki;Tanaka, Takuya;Ohmori, Yasuji
    • E2M - 전기 전자와 첨단 소재
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    • 제11권11호
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    • pp.53-65
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    • 1998
  • Planar lightwave circuits (PLCs) provide various important devices for optical wavelength division multiplexing (WDM) systems, subscriber networks and etc. This paper reviews the recent progress and future prospects of PLC technologies including arrayed-waveguide grating multiplexers, optical add/drop multiplexers, programmable dispersion equalizers and hybrid optoelectronics integration technologies.

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대용량 광신호 연결을 위한 평판 마이크로 광학계 (Planer microoptics for massively parallel aptical interconnections)

  • 송석호
    • 한국광학회:학술대회논문집
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    • 한국광학회 1995년도 광학 및 양자전자학 워크샵 논문집
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    • pp.43-52
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    • 1995
  • For massicely parallel optical interconnections, we propose three types of planar optical configurations for crossover photonic switching netweek, backboard optical signal distribution, and high speed packet address detection. The planar overalsy allow 2-D pixel arrays located on a wafer scale intergated circuit to be interconnected in a compact and vibrationally robust configuration. By the laser writing technique surface relief of microopical Fresnel lenses and multiplex gratigs used in the planar optics are successfully fabricated.

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3차원 해석에 의한 유입변압기 PD발생점 탐지 (PD Source Detection of Oil Transformer Using Three-dimensional Construction)

  • 윤철섭;최길수;이은석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.1036-1038
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    • 1998
  • The while, PD source detection in the oil TR was the level of the planar source detection. and it is to respected scientific research. The planar source detection technique had limits which have difficulties finding out the point of deterioration generation. In this study, our purpose is a development of PD source detection technique with Three-Dimensional using a principle and a technique of the planar source location.

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Design of Scannable Non-uniform Planar Array Structure for Maximum Side-Lobe Reduction

  • Bae, Ji-Hoon;Kim, Kyung-Tae;Pyo, Cheol-Sig;Chae, Jong-Suk
    • ETRI Journal
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    • 제26권1호
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    • pp.53-56
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    • 2004
  • In this letter, we propose a novel design scheme for an optimal non-uniform planar array geometry in view of maximum side-lobe reduction. This is implemented by a thinned array using a genetic algorithm. We show that the proposed method can maintain a low side-lobe level without pattern distortion during beam steering.

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Wideband Rectangular Planar Monopole Antenna for OAM Wave Generation

  • Qasem, Nidal;Alamayreh, Ahmad
    • International Journal of Computer Science & Network Security
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    • 제21권3호
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    • pp.55-59
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    • 2021
  • Generating electromagnetic waves with Orbital Angular Momentum (OAM) properties is a fast-growing research subject in both radio and optics. This paper describes the generation of OAM carrying waves using a circular array of rectangular planar monopole antennas. The proposed design combines simplicity, compactness, and most importantly very wideband of operating frequencies (about 20-160 GHz, bandwidth ratio about 1:8) which makes it suitable for future applications.

Conducting Polymer Material Characterization Using High Frequency Planar Transmission Line Measurement

  • Cho, Young-Seek;Franklin, Rhonda R.
    • Transactions on Electrical and Electronic Materials
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    • 제13권5호
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    • pp.237-240
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    • 2012
  • A conducting polymer, poly 3-hexylthiophene (P3HT) is characterized with the metal-insulator-semiconductor (MIS) measurement method and the high frequency planar circuit method. From the MIS measurement method, the relative dielectric constant of the P3HT film is estimated to be 4.4. For the high frequency planar circuit method, a coplanar waveguide is fabricated on the P3HT film. When applying +20 V to the CPW on P3HT film, the P3HT film is in accumulation mode and becomes lossy. The CPW on P3HT film is 1.5 dB lossier than the CPW on $SiO_2$ film without P3HT film at 50 GHz.

초음파(超音波) 탐촉자 특성(特性)이 판형결함(板形缺陷)의 크기 평가(評價)에 미치는 영향(影響) (The effect of ultrasonic search units on the detectability and size evaluation of planar flaws)

  • 이종포;김병철;임형택;주영상
    • 비파괴검사학회지
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    • 제6권2호
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    • pp.46-56
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    • 1987
  • The effect of ultrasonic search units on the detectability and size evaluation of planar flaws was studied for thicker ferritic material using the technique of the DAC curve and reference level. Cylindrical holes were used as calibration reflectors. The planar flaws such as disc and band types were machined. They were detected and evaluated with different search units and sizing criteria. The value evaluated was compared with the actual dimension of planar flaws.

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Study of the Energy Level Alignment of Organic Materials' Planar Junction Prepared by Electrospray Vacuum Deposition

  • 김지훈;홍종암;서재원;권대견;맹민재;박용섭
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.235-235
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    • 2012
  • We investigated the energy levels of valence region at the planar junction of poly (3-hexylthiophene) (P3HT) and C61-butyric acid methylester (PCBM) using ultraviolet photoemission spectroscopy (UPS) with ultra high vacuum. These are the most widely used materials for bulk heterojunction (BHJ) organic solar cells due to their high efficiency. In order to make the planar junction, we carried out the electrospray vacuum deposition (EVD) of PCBM onto spin-coated P3HT in high vacuum conditions (${\sim}10^{-5}-10^{-6}$). The planar junction interface exhibited 0.71 eV for the offset between P3HT HOMO and PCBM LUMO, which is different from the gap (0.85 eV) of individual values and is closer to the open circuit voltage of solar cells fabricated with the same material combination.

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순간중심을 이용한 평면 3 자유도 자동차 모델의 롤 운동 해석 (Roll Motion Analysis of a 3 D.O.F. Planar Car Model using Instantaneous Centers)

  • 이재길;심재경
    • 한국자동차공학회논문집
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    • 제14권4호
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    • pp.92-98
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    • 2006
  • In this paper, a planar car model with 3 degrees of freedom was analyzed using the concept of the roll center. To avoid ambiguity, force components which require experimental data were excluded. Only kinematic approach was used to find the position and orientation of the vehicle body and the position of the roll center. The roll center was found by the pole with infinitesimal movement and Kennedy-Aronhold theorem. Centrodes, which are the loci of instantaneous centers of planar motion, were constructed with analyzed results to show characteristics of vehicle body motion. To verify the presented analysis method in this paper, the locus of the roll center and the motion of a 3 D.O.F. planar car model were compared with those of the 1 D.O.F. model.