• 제목/요약/키워드: image rejection

검색결과 136건 처리시간 0.034초

Neural Network를 이용한 고무 타이어의 돌출 문자 인식 (Raised characters rocognition of rubber tires using neural network)

  • 김경민;박중조;김민기;박귀태
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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    • pp.864-869
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    • 1993
  • This paper presents the problem of automatically recognizing embossed or molded characters which are raised from the side wall on rubber tire. In the tire image objects have approximately the same gray-value as the background and because of the tire geometry, illumination of the surface is nonhomogenous. Therefore it is difficult to recognize the raised tire character. In this paper, for describing the process of processing three steps have been proposed: 1) MIN & MAX smoothing operation filter, 2) edge detection algorithm using modified laplacian operator, 3) noise rejection. Afterwards, segmentation is done to attain characters from tire image by projection method. The recognition of the characters in the segmented image is carried out by using multilayered neural network, which is insensitive to the noise.

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A study on evaluating the spatial distribution of satellite image classification error

  • Kim, Yong-Il;Lee, Byoung-Kil;Chae, Myung-Ki
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.213-217
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    • 1998
  • This study overviews existing evaluation methods of classification accuracy using confusion matrix proposed by Cohen in 1960's, and proposes ISDd(Index of Spatial Distribution by distance) and ISDs(Index of Spatial Distribution by scatteredness) for the evaluation of spatial distribution of satellite image classification errors, which has not been tried yet. Index of spatial distribution offers the basis of decision on adoption/rejection of classification results at sub-image level by evaluation of distribution, such as status of local aggregation of misclassified pixels. So, users can understand the spatial distribution of misclassified pixels and, can have the basis of judgement of suitability and reliability of classification results.

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Optimized Optomechanical Anti-Aliasing Filter for Digital Camera Photography

  • Lee, Sang Won;Chang, Ryungkee;Moon, Sucbei
    • Journal of the Optical Society of Korea
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    • 제19권5호
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    • pp.456-466
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    • 2015
  • We investigated an anti-aliasing (AA) filter for digital camera photography by which the excessively high-frequency components of the image signal are suppressed to avoid the aliasing effect. Our optomechanical AA filter was implemented by applying rapid relative motions to the imaging sensor. By the engineered motion blur of the mechanical dithers, the effective point-spread function (PSF) of the imaging system could be tailored to reject the unwanted high-frequency components of the image. For optimal operations, we developed a spiral filter motion protocol that could produce a Gaussian-like PSF. We experimentally demonstrated that our AA filter provides an improved filtering characteristic with a better compromise of the rejection performance and the signal loss. We also found that the pass band characteristic can be enhanced further by a color-differential acquisition mode. Our filter scheme provides a useful method of digital photography for low-error image measurements as well as for ordinary photographic applications where annoying $moir{\acute{e}}$ patterns must be suppressed efficiently.

차량 후방 연속 영상에서 오정합점 제거방법 (False Match Rejection in Rear View Camera Image Sequences)

  • 서재규;배광혁;김재희
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.327-328
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    • 2006
  • This paper proposes a method for rejecting false matches in automobile rear view camera image sequences. Our method consists of two submethods which utilize the motion characteristics of an automobile. One is for a straight motion and the other is for a curve motion. First, we classify an image sequence into a straight motion or a curve motion and then apply an appropriate submethod. Our method works in cases where the percentage of true matches is as low as 30%.

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적응형 간섭제거 중계기에서의 이미지 제거를 통한 성능 개선 (Performance Improvement of Adaptive Interference Cancellation Repeater based on Image Rejection)

  • 김원택;권종화;박경호;김주완;하성희;반지훈;이종현
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2007년도 하계종합학술대회 논문집
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    • pp.117-118
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    • 2007
  • The received signal of ICS repeater is composed of BS(Base Station) and feedback signals. In this case, if the feedback signal is not rejected, system is oscillated. we use the IF signal for rejecting the feedback signal at ICS system. In general, SAW filter is used to reject the image of If signal. the use of this filter generates the system delay problems. In this paper, instead of SAW filter we use the Hilbert transform for rejecting image signal.

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페미니즘적 의상의 성적 이미지 지각에 관한 연구 (A study on the Perception of Feministic Fashion's Sexual Image)

  • 권미정;남후선;이정은
    • 대한가정학회지
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    • 제37권11호
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    • pp.97-113
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    • 1999
  • The purpose of this is to analyze the perception of sex image by feministic fashion based on the theory of feminism, which has been developed since the 1960’s. Feministic fashion is divided 8 style and analyzed. For this study, surveying photo of feministic fashion and making out questionnaires. The data was collected from 391 university student(184 male, 207 female) living in Taegu and Kyoungpok and is analyzed by factor analysis, t-test. The result are as follows: 1. The Tendency of perceiving Feministic Fashion’s Sexual Image Male had more positive view on the sexual image of see-through and Body-conscious styles than female. And male showed more negative view on the sexual image of lingerie, punk, madonna or disorganized style. There was no significant difference between male and female in their opinion on the sex appeal of fashion that exposed some physical part. Concerning the sexual image of unisex mode, both male and female had an idea that it had nothing to do with sex appeal. Regarding the preference for sex-expressive fashion, they favored see-through and Body-conscious styles most. 2. In relation to clothing behavior toward sex-expressive fashion, both male and female generally revealed a negative view on fashion that exposed physical part and provoked an impression of keen sex appeal. 3. Sexual perception degree about the body, in physical exposure, that physical part from which they felt sex appeal most was the breast. What they most wanted to emphasize was the breast, too. As a physical part that caused their rejection symptom and made them feel hatred both and female pointed out the hips.

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L1/L2 이중-밴드 GPS 수신기용 RF 전단부 설계 (Design of the RF Front-end for L1/L2 Dual-Band GPS Receiver)

  • 김현덕;오태수;전재완;김성균;김병성
    • 한국전자파학회논문지
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    • 제21권10호
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    • pp.1169-1176
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    • 2010
  • 본 논문에서는 L1/L2 이중-밴드 GPS(Global Positioning System) 수신기용 RF 전단부를 설계하였다. 수신기는 Low IF 구조이며, 인덕터를 사용하지 않는 광대역 저잡음 증폭기(Low Noise Amplifier: LNA)와 이미지 제거를 위하여 다상 여과기(poly-phase filter)를 포함하는 quadrature 하향 변환 주파수 혼합기(quadrature down-conversion mixer) 및 전류 모드 논리(Current Mode Logic: CML) 주파수 분배기로 구성되어 있다. 저잡음 증폭기와 이미지 제거 주파수 혼합기는 높은 이득과 헤드룸 문제를 해결하기 위하여 전류 블리딩 기술을 이용하였으며, 광대역 입력 정합을 구현하기 위하여 공통 드레인 피드백을 이용하였다. $0.18{\mu}m$ CMOS 공정을 이용해 제작된 RF 전단부는 L1 밴드에서 38 dB 그리고 L2 밴드에서 41 dB의 이득을 보이며, IIP3는 L1 밴드에서 -29 dBm, L2 밴드에서는 -33 dBm이다. 입력 정합은 50 MHz에서 3 GHz까지 -10 dB 이하를 만족하며, 잡음 지수(Noise Figure: NF)는 L1 밴드에서는 3.81dB, L2 밴드에서는 3.71 dB를 보인다. 이미지 주파수 제거율은 36.5 dB이다. 설계된 RF 전단부의 칩 사이즈는 $1.2{\times}1.35mm^2$이다.

저궤도 위성용 S-BAND 수신기 설계 및 제작 (Design and Fabrication of a S-BAND Receiver for Low Orbit Satellite)

  • 최영진
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2005년도 추계종합학술대회
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    • pp.35-38
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    • 2005
  • In this study, S-Band receiver for low orbit satellite is implemented. The developed receiver is double super-heterodyne type and STDN compatible. Input/output frequency of receiver is 2034.747MHz and 18.414MHz used for KOMPSAT 2 satellite. Overall gain(@AGC=0V) and image rejection were 92.4dB and 50.2dB respectively. It was verified that receiver has stable performance to the temperature limit, power supply voltage variation and input signal level range.

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Dual Gate FETs에 의한 마이크로파 이미지신호 제거특성 분석 (Analysis of Microwave Image signal Rejection using the Dual Gate FETs)

  • 심재우;이경보;이강훈;이영철
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2001년도 추계종합학술대회
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    • pp.234-237
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    • 2001
  • 본 논문은 마이크로파 수신기시스템에서 발생되는 이미지성분을 효과적으로 제거하기 위해서 Dual Gate FETs을 이용한 이미지 제거 특성을 분석하였다. Dual Gate를 이용한 이미지 제거능력을 모의 실험한 결과 RF신호에 대한 이미지 제거특성은 -32dBc을 보였으며, Dual Gate FETs믹서의 변환이득은 1.7 dBm, 5GHz 발진주파수는 -117.3 dBc/100KHz 임을 확인하였다.

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기판상의 인덕터를 이용한 박막 공진 여파기의 대역 외 저지특성 개선 연구 (A Study on the Out-of-Band Rejection Improvement of TFBAR Ladder Filter using On-Wafer Inductors)

  • 김종수;구명권;육종관
    • 한국전자파학회논문지
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    • 제15권3호
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    • pp.284-290
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    • 2004
  • 본 논문에서는 기판상의 인덕터가 박막공진 여파기의 성능에 미치는 영향을 고찰하기 위하여 두 종류의 사다리형 박막공진 여파기를 설계 및 제작하였다. 여파기를 이루고 있는 박막공진기들의 압전물질은 AIN이고, 전극은 백금(Pt)으로 이루어졌으며 기판에 의한 오버모드(overmode) 현상을 제거하기 위하여 air-gap 형태로 제작되었다. 듀플렉서를 이루고 있는 송신용 여파기의 특성을 보이기 위해 4개의 직렬 공진기와 2개의 병렬 공진기로 이루어진 사다리형 4/2단 여파기가 제작되었으며, 수신용 여파기의 성능을 보이기 위해서는 3/4단으로 제작되었다. 여파기의 성능을 개선하기 위해 사용된 기판상의 인덕터들은 2 ㎓ 대역에서 약 5∼9 정도의 Q값 특성을 보였으며, 인덕터가 연결된 여파기는 연결되지 않은 경우에 비해 약 10∼12 ㏈ 정도의 개선된 대역외 저지특성을 보였다.