• 제목/요약/키워드: array

검색결과 9,431건 처리시간 0.041초

Simultaneous Optimization of Multiple Responses to the Combined Array

  • 권용만
    • Journal of the Korean Data and Information Science Society
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    • 제12권2호
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    • pp.57-64
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    • 2001
  • In the Taguchi parameter design, the product-array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined-array approach, was suggested by Welch et al (1990) and studied by Vining and Myers (1990) and others. In these studies, only single respouse variable was considered. We propose how to simultaneously optimize multiple responses when there are correlations among responses.

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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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THE LONG BASELINE ARRAY

  • EDWARDS, PHILIP G.;PHILLIPS, CHRIS
    • 천문학논총
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    • 제30권2호
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    • pp.659-661
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    • 2015
  • The Long Baseline Array is an array of radio telescopes using the technique of Very Long Baseline Interferometry to achieve milli-arcsecond-scale angular resolution. The core telescopes are located in Australia, with telescopes in New Zealand and South Africa also participating regularly. In this paper the capabilities of the Long Baseline Array are described, and examples of the science undertaken with the array are given.

선형 Halbach 배열의 자기부상열차 제동시스템의 적용 (Linear Halbach array application of MagLev brake system)

  • 장석명;차상도;이성호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.318-320
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    • 2001
  • This paper deal with analysis linear Halbach array. For the theoretical analysis of linear Halbach array, each magnetic vector of permanent magnet is displied by the Furiere series. A result of analytical method to calculate the magnetic flux density compared with a result of numerical method. when linear Halbach array moves above a conductivity material, a developed force between linear Halbach array and a closed loop is analyzed by the theoretical analysis.

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Wideband Capon Beamforming for a Planar Phased Radar Array with Antenna Switching

  • Lee, Moon-Sik
    • ETRI Journal
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    • 제31권3호
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    • pp.321-323
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    • 2009
  • A wideband beamforming algorithm for estimating the azimuth angle, elevation angle, velocity, and range using a planar phased radar array with antenna switching is proposed. It uses the time-variant steering vector model. Simulation results illustrating the performance of the proposed beamformer are presented.

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Schelkunoff 다항식을 사용한 다중의 넓은 Null들을 가지는 선형 배열 안테나 패턴 합성 (Synthesis of Linear Antenna Array Patterns with Multiple Broad Nulls Using Schelkunoff Polynomial)

  • 박의준
    • 한국전자파학회논문지
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    • 제22권12호
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    • pp.1132-1138
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    • 2011
  • 본 논문에서는 간섭 신호 방향으로 넓은 폭의 null(BN)들을 가지도록 하는 선형 배열 안테나 패턴 합성 방법을 새로이 제안한다. 배열 소자들의 가중치들을 최적화시켜 BN을 제어하는 기존의 방법과는 달리, 본 방법에서는 배열계수를 Schelkunoff 다항식으로 변환하고, 이 다항식에 내재된 영점들을 최적 섭동시킴으로써 다중의 BN 방향 및 폭의 제어를 간단히 하였다. 또한, 이 방법은 위상 배열 안테나에도 쉽게 적용됨을 보였다. 도출된 복소 가중치들을 배열계수에 대입함으로써 제안한 방법의 타당성을 수치적으로 검증하였다.

공초점 현미경용 장초점 마이크로렌즈 제작 (Fabrication of Micro-Lens Array with Long Focal Length for Confocal Microscopy)

  • 김기홍;임형준;정미라;이재종;최기봉;이형석;도이미
    • 한국생산제조학회지
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    • 제20권4호
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    • pp.472-477
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    • 2011
  • This paper shows the method of fabrication of a micro lens array comprised of a Nipkow disk used in a large-area, high-speed confocal microscopy. A Nipkow disk has two components, a micro lens array disk and a pinhole array disk. The microlens array focuses illumination light onto the pinhole array disk and redirects reflected light from a surface to a sensor. The micro lens which are positioned in order on a disk have a hemispheric shape with a few tens of micron in diameter, and can be fabricated by a variety of methods like mechanical machining, semiconductor process, replication process like imprinting process. This paper shows how to fabricate the micro lens array which has a long focal length by reflow and imprinting process.

Planar Array of a Probe Excited Circular Ring Radiating Bidirectional Pattern

  • Phongcharoenpanich, Chuwong;Sroysuwan, Thanarart;Wounchoum, Phairote;Kosulvit, Sompol;Krairiksh, Monai
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.719-722
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    • 2002
  • This paper reports the characteristics of a bidirectional antenna by using a planar array of a probe excited circular ring. The element of a bidirectional antenna is first designed to achieve the maximum directivity. The directivity can be further increased by arranging these elements to form the linear array. There are two types of linear array to be investigated i.e., on axis and off axis arrangement. On-axis linear array yields better directivity than off-axis linear array. Therefore, this orientation is further used to form the planar array. The radiation characteristics of this optimum planar array are rigorously reported. The proposed structure is very useful to extend the distance between the base station in PCT system.

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주파수영역 빔형성 기법을 이용한 3차원 소음원 가시화 (Study on 3D Sound Source Visualization Using Frequency Domain Beamforming Method)

  • 황은수;이재형;이욱;최종수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.490-495
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    • 2009
  • An approach to 3D visualization of multiple sound sources has been developed with the application of a moving array technique. Frequency-domain beamforming algorithm is used to generate a beam power map and the sound source is modeled as a point source. When a conventional delay and sum beamformer is used, it is considered that 2D distribution of sensors leads to have deficiency in spatial resolution along a measurement distance. The goal of moving an array in this study is to form 3D array aperture surrounding multiple sound sources so that the improved spatial resolution in a virtual space can be expected. Numerical simulation was made to examine source localization capabilities of various shapes of array. The 3D beam power maps of hemispherical and spherical distribution are found to have very sharp resolution. For experiments, two sound sources were placed in the middle of defined virtual space and arc-shaped line array was rotated around the sources. It is observed that spherical array show the most accurate determination of multiple sources' positions.

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주파수영역 빔형성 기법을 이용한 3차원 소음원 가시화 (Study on 3D Sound Source Visualization Using Frequency Domain Beamforming Method)

  • 황은수;이재형;이욱;최종수
    • 한국소음진동공학회논문집
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    • 제19권9호
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    • pp.907-914
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    • 2009
  • An approach to 3D visualization of multiple sound sources has been developed with the application of a moving array technique. Frequency domain beamforming algorithm is used to generate a beam power map and the sound source is modeled as a point source. When a conventional delay and sum beamformer is used, it is considered that 2D distribution of sensors leads to have deficiency in spatial resolution along a measurement distance. The goal of moving an array in this study is to form 3D array aperture surrounding multiple sound sources so that the improved spatial resolution in a virtual space can be expected. Numerical simulation was made to examine source localization capabilities of various shapes of array. The 3D beam power maps of hemispherical and spherical distribution are found to have very sharp resolution. For experiments, several sound sources were placed in the middle of defined virtual space and arc-shaped line array was rotated around the sources. It is observed that spherical array shows the most accurate determination of multiple sources' positions.