• 제목/요약/키워드: Noise matching

검색결과 549건 처리시간 0.027초

A FAST TEMPLATE MATCHING METHOD USING VECTOR SUMMATION OF SUBIMAGE PROJECTION

  • Kim, Whoi-Yul;Park, Yong-Sup
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1999년도 KOBA 방송기술 워크샵 KOBA Broadcasting Technology Workshop
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    • pp.171-176
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    • 1999
  • Template matching is one of the most often used techniques for machine vision applications to find a template of size M$\times$M or subimage in a scene image of size N$\times$N. Most template matching methods, however, require pixel operations between the template and the image under analysis resulting in high computational cost of O(M2N2). So in this thesis, we present a two stage template matching method. In the first stage, we use a novel low cost feature whose complexity is approaching O(N2) to select matching candidates. In the second stage, we use conventional template matching method to find out the exact matching point. We compare the result with other methods in terms of complexity, efficiency and performance. Proposed method was proved to have constant time complexity and to be quite invariant to noise.

의료기기용 MedRadio 대역 저전력 저잡음 증폭기 (A MedRadio-Band Low Power Low Noise Amplifier for Medical Devices)

  • 김태종;권구덕
    • 전자공학회논문지
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    • 제53권9호
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    • pp.62-66
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    • 2016
  • 본 논문에서는 의료기기용 MedRadio 대역의 저전력 저잡음 증폭기를 제안한다. 제안한 저잡음 증폭기는 전류 재사용 저항 피드백 증폭기 구조를 채택하여 $g_m$을 증폭시키고 소스 인덕터 없이 입력 매칭을 가능하도록 하였다. 추가적으로 제안한 직렬 저항, 인덕터, 커패시터 입력 매칭 네트워크의 Q-factor를 통해 저잡음 증폭기의 전압 이득을 증가시켜 잡음 지수를 최소화 했다. 로드저항이 없는 구조를 채택하여 낮은 전원 전압으로 전력 소모를 줄였다. 제안한 MedRadio 대역 저전력 저잡음 증폭기는 $0.13{\mu}m$ CMOS 공정을 사용하여 설계하였고, 전원 전압 1 V에서 0.18 mA의 전류를 소모하면서 0.85 dB의 잡음 지수, 30 dB의 전압 이득, -7.9 dBm의 IIP3의 성능을 보인다.

Sound Field Controller Design Method based on Partial Model Matching on Frequency Domain

  • Kumon, Makoto;Eguchi, Kazuki;Mizumoto, Ikuro;Iwai, Zenta
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1398-1403
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    • 2003
  • In this paper, a simple method to design an MIMO sound field control system was proposed. The control system was designed to achieve 1) noise attenuation and 2) sound equalization by utilizing feedback and feedforward controllers. The method was based on partial model matching on frequency domain which only required measured frequency response data, or impulse response data in order to tune parameters of the controller. The proposed method was applied to a normal office room and results of experiment showed effectiveness of the proposed method.

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홍채 인식 성능에 영향을 미치는 화질 저하 요인 분석 (Analysis on Iris Image Degradation Factors)

  • 윤소원;김재희
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.863-864
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    • 2008
  • To predict the iris matching performance and guarantee its reliability, image quality measure prior to matching is desired. An analysis on iris image degradation factors which deteriorate matching performance is a basic step for iris image quality measure. We considered five degradation factors-white-out, black-out, noise, blur, and occlusion by specular reflection-which happen generally during the iris image acquisition process. Experimental results show that noise and white-out degraded the EER most significantly, while others on EER were either insignificant or degradation images resulted in even better performance in some cases of blur. This means that degradation factors that affect the performance can be different from those based on human perception or image degradation evaluation.

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유도 초음파 이용 결함 진단을 위한 정합추적 기법 (Matching Pursuit Approach for Guided Wave-based Damage Inspection)

  • 홍진철;선경호;김윤영
    • 한국소음진동공학회논문집
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    • 제15권4호
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    • pp.382-387
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    • 2005
  • For successful guided-wave damage inspection, the appropriate signal processing of measured wave signals is very important. The objective of this paper is to introduce an efficient signal processing technique especially suitable for the guided-waves used for damage detection. The key idea of this technique is to model guided-waves by chirp functions of special form considering the dispersion phenomenon. To determine the parameter of the chirp functions simulating guided-waves, the matching pursuit algorithm is employed. The damage information in waveguides can be extracted by pulse-characterizing parameters. The effectiveness of present method is checked with the guided wave-based damage inspection.

가보 펄스 기반 정합추적 알고리즘 : 웨이브가이드 결함진단에서의 응용 (Gabor Pulse-Based Matching Pursuit Algorithm : Applications in Waveguide Damage Detection)

  • 선경호;홍진철;김윤영
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.969-974
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    • 2004
  • Although guided-waves are very efficient for long-range nondestructive damage inspection, it is not easy to extract meaningful pulses of small magnitude out of noisy signals. The ultimate goal of this research is to develop an efficient signal processing technique for the current guided-wave technology. The specific contribution of this investigation towards achieving this goal, a two-stage Gabor pulse-based matching pursuit algorithm is proposed : rough approximations with a set for predetermined parameters characterizing the Gabor pulse and fine adjustments of the parameters by optimization. The parameters estimated from the measured signal are then used to assess not only the location but also the size of a crack existing in a rod. To validate the effectiveness of the proposed method, the longitudinal wave-based damage detection in rods is considered. To estimate the crack size, Love's theory for the dispersion of longitudinal waves is employed.

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A Transformer Feedback CMOS LNA for UWB Application

  • Jeon, Ji Yeon;Kim, Sang Gyun;Jung, Seung Hwan;Kim, In Bok;Eo, Yun Seong
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권6호
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    • pp.754-759
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    • 2016
  • A transformer feedback low-noise amplifier (LNA) is implemented in a standard $0.18{\mu}m$ CMOS process, which exploits drain-to-gate transformer feedback technique for wideband input matching and operates across entire 3~5 GHz ultra-wideband (UWB). The proposed LNA achieves power gain above 9.5 dB, input return loss less than 15.0 dB, and noise figure below 4.8 dB, while consuming 8.1 mW from a 1.8-V supply. To the authors' knowledge, drain-to-gate transformer feedback for wideband input matching cascode LNA is the first adopted technique for UWB application.

23GHz대 1단 저잡음 증폭기의 설계 기술에 관한 연구 (A study on the design technologies for the 1-state 23GHz LNAs)

  • 장동필;안동식
    • 한국통신학회논문지
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    • 제22권5호
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    • pp.974-980
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    • 1997
  • The 23GHz 1-state LNA was designed by using MPIE numerical analysis and conventional design EEsof softwares. The circuit was designed using conventional tools but analyzed and modified by using numerical MPIE tools. he matching sections was designed with parallel coupled filter-type, which gives impedance matching and DC blocking and has small discontinuities. THe FET chip is directly attached to the graound metal. The designed LNA gives 5.8dB gain and 2.5dB noise figure withoug considering the loss and impedance shift of connectors that degenerate the gain and noise figure considerably. this results gives very promising characteristics for our design process and matching schemes and fabrication technologies.

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불일치 절점을 가지는 경우의 축약된 모델을 이용한 동특성 변경법 (Structural Dynamics Modification using Reduced Model for Having Non-matching Nodes)

  • 강옥현;박윤식;박영진
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.830-833
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    • 2005
  • SDM(Structural Dynamics Modification) is to improve dynamic characteristics of a structure, more specifically of a base structure, by adding or deleting auxiliary(modifying) structures. In this paper, I will focus on the optimal layout of the stiffeners which are attached to the plate to maximize 1st natural frequency. Recently, a new topology method was proposed by yamazaki. He uses growing and branching tree model. I modified the growing and branching tree model. The method is designated modified tree model. To expand the layout of stiffeners, I will consider non-matching problem. The problem is solved by using local lagrange multiplier without the mesh regeneration. Moreover The CMS(Component mode synthesis) method is employed to reduce the computing time of eigen reanalysis using reduced componet models.

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유도 초음파 이용 결함 진단을 위한 정합추적 기법 (Matching Pursuit Approach for Guided Wave-Based Damage Inspection)

  • 홍진철;선경호;김윤영
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.615-618
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    • 2004
  • For successful guided-wave damage inspection, the appropriate signal processing of measured wave signals is very important. The objective of this paper is to introduce an efficient signal processing technique especially suitable for the guided-waves used for damage detection. The key idea of this technique is to model guided-waves by chirp functions of special form considering the dispersion phenomenon. To determine the parameter of the chirp functions simulating guided-waves, the matching pursuit algorithm is employed. The damage information in waveguides can be extracted by pulse-characterizing parameters. The effectiveness of present method is checked with the longitudinal wave-based damage inspection.

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