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검색결과 7,003건 처리시간 0.044초

퍼지 이론을 사용한 Sensor-based Local Homing 알고리즘 개발 (Sensor-based Local Homing Algorithm using Fuzzy Theory)

  • 방석원;이지연;김성도;유원필;정명진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 A
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    • pp.387-390
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    • 1993
  • The most important technique for an indoor robot navigation is to find out the direction and the distance from the current location to the destination through the information achieved from the sensor. For this purpose, we suggest sensor-based local homing method which compares the destination sensory data with the current location. As for the sensors, we use the CCD camera and the ultrasonic sensor, and recorded entire 360 degree panoramic data. We match the features of the image data, and the distance and the direction of the matched point will be considered as fuzzy numbers. Through a simple fuzzy arithmetic, we infer the geometric relations between the current location and the destination location.

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하드 스위칭 인버터를 위한 새로운 IGBT용 게이트 드라이버 (A New IGBT Gate Driver for Hard Switching Inverter)

  • 정용채;김학성;정재훈;이병우;조규형
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 B
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    • pp.746-748
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    • 1993
  • To overcome the problem of the diode reverse recovery in high switching frequency inverter, a new gate drive scheme is proposed for IGBT in this paper. Using this circuit, the reverse recovery current can be controlled and faster switching time can be achieved for hard switching inverter. The over-current protection method, which is suitable for the proposed gate driver, is also presented. The operation of the proposed circuit is investigated and its usefulness is verified through the experimental results.

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Automated Image Receiving and Processing System for Landsat 7

  • Park, Sung-Og;Kim, Moon-Gyu;Kim, Tae-Jung;Ji-Hyeon, Shin;Choi, Myung-jin;Park, Jeong-Hyun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.573-577
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    • 2002
  • The Landsat Program is the longest running enterprise for acquisition of imagery of the Earth from space. The first Landsat satellite was launched in 1972 and the most recent, Landsat 7, was launched on April 15, 1999. The Landsat satellites have acquired millions of images. The Landsat 7 receiving station is installed at more than 25 sites and will be installed in Korea. This paper will address the work being carried out for the development of image receiving and processing system for the Landsat 7 image data, which will be used at ground station of Landsat 7 in Korea.

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휴대폰용 카메라 모듈의 조립에 대한 연구 (A Research on the Assembly of the Camera Modules for Mobile Phones)

  • 최재성;이경수;임동현;송준엽;이창우;곽윤근;김수현
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.989-992
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    • 2005
  • This paper is about the assembly of camera modules for mobile phones. We have particularly researched the assembly process proper for mega-pixel lens assemblies in the camera modules. Herein, we propose that self-adjustment function makes it possible to assemble these lens assemblies without fraction of components. In advance, we observed the assembly process of the lens assemblies to verify the possibility, and checked out it through experiments based on some assumptions.

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Comparison of Slowness Profiles of Lamb Wave with Elastic Moduli and Crystal Structure in Single Crystalline Silicon Wafers

  • Min, Youngjae;Yun, Gyeongwon;Kim, Kyung-Min;Roh, Yuji;Kim, Young H.
    • 비파괴검사학회지
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    • 제36권1호
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    • pp.1-8
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    • 2016
  • Single crystalline silicon wafers having (100), (110), and (111) directions are employed as specimens for obtaining slowness profiles. Leaky Lamb waves (LLW) from immersed wafers were detected by varying the incident angles of the specimens and rotating the specimens. From an analysis of LLW signals for different propagation directions and phase velocities of each specimen, slowness profiles were obtained, which showed a unique symmetry with different symmetric axes. Slowness profiles were compared with elastic moduli of each wafer. They showed the same symmetries as crystal structures. In addition, slowness profiles showed expected patterns and values that can be inferred from elastic moduli. This implies that slowness profiles can be used to examine crystal structures of anisotropic solids.

DB 자동 구축을 위한 필기 형식문서 인식 시스템의 개발 (Development of Handwritten Form Recognition System for Automated Database Construction)

  • 김동준;조성정;류성호;이택헌;김진형
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2000년도 제13회 춘계학술대회 및 임시총회 학술발표 논문집
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    • pp.1047-1050
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    • 2000
  • 형식문서는 현재 정보의 체계화된 표현 및 저장 수단으로서 널리 사용되어 왔다. 최근 이러한 형식문서들을 데이터베이스화해주는 시스템들이 보급되고 있다. 그러나 대부분 외국의 시스템을 기반으로 작성되어 한글, 영어, 숫자, 한자등 다양한 필기 문자들이 사용되는 국내 환경의 특수성을 적절히 반영하지 못하고 있다. 그 결과, 대부분의 경우 아직도 사람이 직접 자료를 입력해야만 한다. 본 논문에서는 이러한 국내 실정에 맞게 다양한 언어의 필기 문자 인식기를 결합하여 형식 문서의 정보를 자동으로 데이터베이스에 입력해 주는 시스템을 제안한다. 제안된 시스템은 영상을 인식한 뒤 그 결과를 검증하는 방법을 통하여 정보의 입력을 보다 효율적으로 수행할 수 있을 뿐 아니라, 전체 작업을 단계별로 분할하여 병렬적으로 수행할 수 있게 함으로써 처리율을 향상시킬 수 있게 하였다.

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지리적 특성을 고려한 클라우드 컴퓨팅 서비스 관리 기법 연구 (Research of GeoLocation based Cloud Computing Service Management)

  • 강동기;김성환;김우중;하윤기;윤찬현
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2013년도 추계학술발표대회
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    • pp.205-207
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    • 2013
  • 멀티 클라우드 서비스 제공자가 연동된 환경에서 각 데이터 센터에 위치하고 있는 물리 노드들의 위치에 따라서 클라우드 서비스 사용자와 연결된 네트워크 속도에 차이가 발생하고 이에 의해서 각 물리 노드에서 생성되는 가상 자원 인스턴스의 작업 처리 성능에도 영향을 미치게 된다. 특히 웹 어플리케이션과 같은 네트워크 성능에 의존도가 높은 응용의 경우 이에 대한 성능 영향의 정도가 매우 크게 증가한다. 본 논문에서는 이러한 문제를 해결하기 위하여 클라우드 서비스 사용자와 가상 자원 인스턴스간의 물리적인 거리 및 동적인 네트워크 상황을 고려한 적응적 가상 자원 할당 기법을 소개한다.

Classification of Arrhythmia Based on Discrete Wavelet Transform and Rough Set Theory

  • Kim, M.J.;J.-S. Han;Park, K.H.;W.C. Bang;Z. Zenn Bien
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.28.5-28
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    • 2001
  • This paper investigates a classification method of the electrocardiogram (ECG) into different disease categories. The features for the classification of the ECG are the coefficients of the discrete wavelet transform (DWT) of ECG signals. The coefficients are calculated with Haar wavelet, and after DWT we can get 64 coefficients. Each coefficient has morphological information and they may be good features when conventional time-domain features are not available. Since all of them are not meaningful, it is needed to reduce the size of meaningful coefficients set. The distributions of each coefficient can be the rules to classify ECG signal. The optimally reduced feature set is obtained by fuzzy c-means algorithm and rough set theory. First, the each coefficient is clustered by fuzzy c-means algorithm and the clustered ...

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Development of confocal scanning microscopy using acousto-optica1 deflector

  • J.W. Seo;D.K. Kang;H.G. Yun;Kim, K.H.;D.G. Gweon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.161.6-161
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    • 2001
  • Confocal scanning microscopy (CSM) has an important role as the three-dimensional profiler. An image distribution can be reconstructed by a correlation analysis of spots with the bandwidth of radio frequency. But it is a serious problem for the high performance to align the optical components. Especially, the parasitic motion of focus on the detector gives rise to the fatal distortion of an image profile named the extinction effect while using acousto-optical(AO) deflector. An image profile can be regenerated in CSM with many advantages of non-contact, high speed and high resolution comparatively. In addition to the axial response of the primary focus, the lateral movement of it gives a necessity of the unitary lens to the scanning system. While using the beam deflector, the pupil of beam may be fixed at the nominal position. Furthermore, the use of a deflector may result in ...

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Displacement measurement sensor using astigmatic confocal technology

  • J.W. Seo;D.K. Kang;Lee, J.H.;Kim, D.M.;D.G. Gweon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.163.2-163
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    • 2001
  • Confocal scanning microscopy (CSM) has been reported as an excellent method using the optical probe in scanning probe microscopy (SPM). Transmission or reflection confocal scanning microscopy (TCSM, RCSM) has been used in the three-dimensional reconstruction of specimen or the non-destructive measurement in vivo. The axial movement of the primary focal point having the information of specimen gives a good measurement performance with the great sensitivity. Application of the confocal theory and astigmatism to displacement measurement sensor uses the aperture as the pinhole or slit after collecting lens relating to confocal response in non-contact measurement; and astigmatic lens using four-segments detector as short-range sensor, long-range one combining the grating and rotary one hating the rotary directional grating. The aperture type can play an ...

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