• Title/Summary/Keyword: 2D arrays

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Adaptive planar vision marker composed of LED arrays for sensing under low visibility

  • Kim, Kyukwang;Hyun, Jieum;Myung, Hyun
    • Advances in robotics research
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    • v.2 no.2
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    • pp.141-149
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    • 2018
  • In image processing and robotic applications, two-dimensional (2D) black and white patterned planar markers are widely used. However, these markers are not detectable in low visibility environment and they are not changeable. This research proposes an active and adaptive marker node, which displays 2D marker patterns using light emitting diode (LED) arrays for easier recognition in the foggy or turbid underwater environments. Because each node is made to blink at a different frequency, active LED marker nodes were distinguishable from each other from a long distance without increasing the size of the marker. We expect that the proposed system can be used in various harsh conditions where the conventional marker systems are not applicable because of low visibility issues. The proposed system is still compatible with the conventional marker as the displayed patterns are identical.

Reliability improvement and real-tiem reconfiguration of fault tolerant VLSI arrays using symmetrical pseudo faulty processing elements genration technique (대칭적 의사결함처리요소 생성 기법에 의한 결함허용 VLSI 어레이의 신뢰도 향상과 실시간 재구성)

  • 신동석;우종호
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.5
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    • pp.188-202
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    • 1996
  • In this paper, we propose a symmetrical pseudo faulty processing elements genration technique to improve the overall reliability of arrays with fixed hardware resources on the fault tolerant VLSI arrays based on single-track switches. We have analyzed the reliability of fault tolerant VLSI arrays and designed control logic for real-tiem reconfiguration. Applying this technique to reconfiguration of VLSI 2-D arrays, we have found that the proposed scheme achieves a higher reliability than the previus methods of similar condition. And we have found that the results of reliability analyzed by mathematic computation are very close to simulated ones. Furthermore, the time overhead for reconfiguration is independent of the array size because the control for reconfiguration is distributively executed by each processing elements. And the proposed scheme has an advantage which maintained properties of VLSI arrays by keeping the locality of interconnections as high as possible even after the reconfiguration.

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A Study on Optimization of Structure for Hexagon Tile Sub-array Antenna System (Hexagon 타일 부배열 안테나 시스템 구조 최적화에 관한 연구)

  • Jung, Jinwoo;Pyo, Seongmin
    • Journal of IKEEE
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    • v.26 no.1
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    • pp.129-132
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    • 2022
  • In this paper, a technique for optimizing the sub-array system structure that can minimize the side lobe level of the phased-array antenna is proposed. Optimization of the proposed array antenna structure is to adjust the spacing between sub-arrays and sub-arrays by using a hexagonal array structure of one sub-array and a hexagonal sub-array for six hexagonal arrays, and thus the entire phased array antenna system of the radiation pattern was optimized. Compared to the 2-dimensional planar antenna system, the proposed technique maintains a gain of 24.3 dBi and a half-power beam-width of 8.46 degrees without change, and only reduces -3.4 dB and -6.5 dB in the x-axis and y-axis directions, respectively.

A two-dimensional positioning system by use of correlation of vague M-arrays

  • Kashiwagi, Hiroshi;Sakata, Masato;Ohtomo, Atsushi
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.1059-1062
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    • 1989
  • This paper describes a new method for two-dimensional(2D) positioning system by use of crosscorrelation of vague M-arrays. An M-array pattern is attached on an object to be positioned and it is observed by a TV camera in out-of-focus condition. The crosscorrelation between the observed image data and the reference M-array gives us the information about the 2D position of the object.

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Effectiveness of the Electrode Arrays for Delineating 2-D Subsurface Structure (2차원 지하구조 규명을 위한 전극배열의 효율성)

  • Yoon, Jong-Ryeol;Lee, Kiehwa
    • Economic and Environmental Geology
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    • v.29 no.3
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    • pp.345-355
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    • 1996
  • The effectiveness of various electrode configurations in horizontal mappings and 1-D inversions of vertical sounding data for delineating 2-D structures was studied. Apparent resistivity values of three point, dipole-dipole, Wenner, and Schlumberger mappings were simulated for such structures as vertical dyke, tabular prism, buried vertical fault, ramp and complex structure by finite difference method (FDM) and they were compared with each other. Also 2-D cross sections for three structures obtained by interpolation of 1-D inverted sounding data in terms of three layers were compared for Schlumberger and Wenner arrays. On these cross sections, horizontal and vertical resistivity interfaces of the 2-D structures are revealed relatively clearly. Apparent resistivity curves of Schlumberger mapping show vertical resistivity discontinuities very well. On the whole, Schlumberger array is superior to the other arrays in electric sounding as well as mapping. This study clearly indicates that interpretations of 2-D structures based on 1-D inversion are possible.

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Scan Blindness Analysis of 1D and 2D Ka-Band Printed Dipole Array Antenna (일차원과 이차원 Ka-대역 프린티드 다이폴 배열 안테나의 스캔 블라인드니스 분석)

  • Koo, Hanni;Song, Sungchan;Nam, Sangwook
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.30 no.3
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    • pp.202-208
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    • 2019
  • In this study, an active element pattern (AEP) of a printed dipole was analyzed in 1D and 2D arrays. First, an AEP of the printed dipole was obtained using the simulation in the 2D infinite array. The scan blindness in the 2D array occurred in the E-plane direction at around ${\pm}36^{\circ}$; however, it was barely observed in the 1D array. To analyze the cause of the scan blindness in the 2D array, the dispersion properties of a unit cell was obtained and compared with the scan blindness by frequency change. The difference between the scan blindness of the 1D and 2D arrays was clarified using the comparison of the Q value in the unit cell in the 1D and 2D arrays. Then, the coupling of the electric field in the E-plane direction was observed when nine elements were separated between the two ports in a linearly arranged dipole structure. Finally, the printed dipole array was fabricated, and an AEP was measured for the $11{\times}1$ and $11{\times}3$ sub arrays. The proposed theory was verified using these observations and by comparison with the simulation results.

MARCINKIEWICZ-TYPE LAW OF LARGE NUMBERS FOR DOUBLE ARRAYS

  • Hong, Dug-Hun;Volodin, Andrei I.
    • Journal of the Korean Mathematical Society
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    • v.36 no.6
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    • pp.1133-1143
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    • 1999
  • Chaterji strengthened version of a theorem for martin-gales which is a generalization of a theorem of Marcinkiewicz proving that if $X_n$ is a sequence of independent, identically distributed random variables with $E{\mid}X_n{\mid}^p\;<\;{\infty}$, 0 < P < 2 and $EX_1\;=\;1{\leq}\;p\;<\;2$ then $n^{-1/p}{\sum^n}_{i=1}X_i\;\rightarrow\;0$ a,s, and in $L^p$. In this paper, we probe a version of law of large numbers for double arrays. If ${X_{ij}}$ is a double sequence of random variables with $E{\mid}X_{11}\mid^log^+\mid X_{11}\mid^p\;<\infty$, 0 < P <2, then $lim_{m{\vee}n{\rightarrow}\infty}\frac{{\sum^m}_{i=1}{\sum^n}_{j=1}(X_{ij-a_{ij}}}{(mn)^\frac{1}{p}}\;=0$ a.s. and in $L^p$, where $a_{ij}$ = 0 if 0 < p < 1, and $a_{ij}\;=\;E[X_{ij}\midF_[ij}]$ if $1{\leq}p{\leq}2$, which is a generalization of Etemadi's marcinkiewicz-type SLLN for double arrays. this also generalize earlier results of Smythe, and Gut for double arrays of i.i.d. r.v's.

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Fabrication of Pair-Photonic Crystal Arrays using Multiple-Exposure Nanosphere Lithography (다중노광 나노구 리소그라피를 이용한 쌍-광자결정 어레이 제작)

  • Yeo, Jong-Bin;Han, Gwang-Min;Lee, Hyun-Yong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.3
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    • pp.245-249
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    • 2010
  • Two dimensional(2D) pair-photonic crystals (pair-PCs) have been fabricated by a multiple-exposure nanosphere lithography (MENSL) method using the self-assembled nanospheres as lens-mask patterns and the collimated laser beam as a multiple-exposing source. The arrays of the 2D pair-PCs exhibited variable lattice structures and shape the control of rotating angle (${\Theta}$), tilting angle (${\gamma}$) and the exposure conditions. In addition, the base period or filling factor of pair-PCs as well as their shapes could be changed by experimental conditions and nanosphere size. A 1.18-${\mu}m$-thick resist was spincoated on Si substrate and the multiple exposure was carried out at change of ${\gamma}$ and ${\Theta}$. Images of prepared 2D pair-PCs were observed by SEM. We believe that the MENSL method is a suitable useful tool to realize the pair-periodic arrays of large area.