• Title/Summary/Keyword: 송환

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Efficiency Characteristics of Half-bridge Series Resonant Converter for the Contact-less Power Supply (Half-bridge 직렬공진 컨버터 적용 무접점 전원장치 효율특성)

  • Lee, Hyun-Kwan;Song, Hwan-Kook;Kim, Eun-Soo;Kim, Yoon-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.5
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    • pp.884-891
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    • 2007
  • Comparing with the conventional transformer without the air gap, a contact-less transformer with the large air-gap (4.8cm) between the long primary winding and the secondary winding has the increased leakage inductance and the reduced magnetizing inductance. By the increased leakage inductance and the reduced magnetizing inductance on the primary of the contact-less transformer, a good deal of the primary current circulates through magnetizing inductance, which results in a massive loss and the high voltage gain characteristics for load variations in contact-less power supply (CPS). To consider these characteristics, in this paper, the efficiency characteristics of the contact-less power supply using a series resonant converter is presented, described and verified through theoretical analysis, computer simulation and experimental test of 2.5kW prototype.

Patent Analysis of e-Navigation Technology in Korea and the US (한국과 미국의 e-내비게이션 기술분야 특허분석 연구)

  • Song, Hwan Been
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 2017.05a
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    • pp.43-65
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    • 2017
  • UN 산하 국제해사기구(IMO)는 2020년 국제적인 시행을 목표로 e-내비게이션 분야의 국제기술표준 개발을 추진 중에 있다. e-내비게이션은 차세대 해양안전 종합관리시스템으로서 각종 해상 운항정보를 디지털화 해 선박 운항자에게 실시간 맞춤형 정보를 제공해 준다. 해수부는 2020년 이후 약 1,000조원의 시장이 열릴 것으로 내다보고 있으며, 진입 장벽이 높은 해양 장비 시장에 우리나라도 ICT 강점을 바탕으로 주도권을 잡기 위해 노력중이다. 이를 위하여 한국과 미국의 e-내비게이션 분야의 핵심기술 중심으로 기술분야별 특허동향, 기술시장 성장 단계, 국가간 기술경쟁력, 그리고 특허 Key Player별 보유 특허 포트폴리오, 피인용 분석을 통한 경쟁력, 특허 거래 및 소송 분석을 통하여 양 국가의 기술개발 동향을 파악하고자 한다.

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3D Head Pose Estimation Using The Stereo Image (스테레오 영상을 이용한 3차원 포즈 추정)

  • 양욱일;송환종;이용욱;손광훈
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.1887-1890
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    • 2003
  • This paper presents a three-dimensional (3D) head pose estimation algorithm using the stereo image. Given a pair of stereo image, we automatically extract several important facial feature points using the disparity map, the gabor filter and the canny edge detector. To detect the facial feature region , we propose a region dividing method using the disparity map. On the indoor head & shoulder stereo image, a face region has a larger disparity than a background. So we separate a face region from a background by a divergence of disparity. To estimate 3D head pose, we propose a 2D-3D Error Compensated-SVD (EC-SVD) algorithm. We estimate the 3D coordinates of the facial features using the correspondence of a stereo image. We can estimate the head pose of an input image using Error Compensated-SVD (EC-SVD) method. Experimental results show that the proposed method is capable of estimating pose accurately.

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Pose Invariant 3D Face Recognition (포즈 변화에 강인한 3차원 얼굴인식)

  • 송환종;양욱일;이용욱;손광훈
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2000-2003
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    • 2003
  • This paper presents a three-dimensional (3D) head pose estimation algorithm for robust face recognition. Given a 3D input image, we automatically extract several important 3D facial feature points based on the facial geometry. To estimate 3D head pose accurately, we propose an Error Compensated-SVD (EC-SVD) algorithm. We estimate the initial 3D head pose of an input image using Singular Value Decomposition (SVD) method, and then perform a Pose refinement procedure in the normalized face space to compensate for the error for each axis. Experimental results show that the proposed method is capable of estimating pose accurately, therefore suitable for 3D face recognition.

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Image Compression Technique using Variable Blocks in the Wavelet Transform Domain (웨이블릿 변환 영역에서의 가변블록을 이용한 영상압축)

  • 권세안;장우영;송환종;손광훈
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1998.06a
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    • pp.181-184
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    • 1998
  • 본 논문에서는 웨이블릿 변환[1]을 기반으로 하여 가변블록을 이용하는 영상압축방식을 제안하였다. 영상을 웨이블릿 변환한 후의 계수들은 각 부밴드별로 그 통계적, 특성, 에너지 특성 그리고 방향 특성 등이 각각 다르기 때문에 이를 이용하여 각 부밴드별로 가변블록을 이용하여 비트할당을 통한 영상압축을 수행한다. 제안 알고리듬에는 손실 압축방식으로서 양자화기를 거친 후에 부가적인 무손실 압축방식으로서 엔트로피를 이용하는 arithmetic 부호화기[2]를 거쳐 최종적으로 압축된 데이터를 얻어낸다. 시뮬레이션 결과 제안알고리듬은 기존 압축알고리즘에 비해 객관적인 향상된 압축률과 PSNR면에서 향상된 성능을 보여주고, 주관적으로는 낮은 BPP를 갖는 압축에서 나타나는 블록화 현상이 나타나지 않음을 확인하였다.

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Improved H.263+ Rate Control via Variable Frame Rate Adjustment and Hybrid I-frame Coding

  • 송환준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.5A
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    • pp.726-742
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    • 2000
  • A novel rte control algorithm consisting of two major components, i.e. a variable encoding frame rate method and a hybrid DCT/wavelet I-frame coding scheme, is proposed in this work for low bit rate video coding. Most existing rate control algorithms for low bit rate video focus on bit allocation at the macroblock level under a constant frame rate assumption. The proposed rate control algorithm is able to adjust the encoding frame rate at the expense of tolerable time-delay. Furthermore, an R-D optimized hybrid DCT/wavelet scheme is used for effective I-frame coding. The new rate-control algorithm attempts to achieve a good balance between spatial quality and temporal quality to enhance the overall human perceptual quality at low bit rates. It is demonstrated that the rate control algorithm achieves higher coding efficiency at low bit rates with a low additional computational cost. The variable frame rate method and hybrid I-frame coding scheme are compatible with the bi stream structure of H.263+.

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Inhibition of Xanthine Oxidase by Flavonols from Onion Skin (양파껍질에서 분리한 플라보놀의 Xanthine Oxidase 저해기작)

  • 서형주;나경수;배송환;손홍수;정수현
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.4
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    • pp.693-697
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    • 1998
  • The influence of flavonols from onion skin on xanthine oxidase was investigated. Methanol extract was showed 12.8% of yield, 661.3mg% of flavonoids contents and 88.7% of inhibitory effect on xanthine oxidase F1 and F2 fractions were obtained from the methanol extract by ODS and Sephadex LH-20 chromatography. F1 and F2 fractions flavonols(3-OH free) identified by UV/visible spectroscopy. Inhibitory effect of F1 and F2 on xanthine oxidase were increased with increasing concentration. IC50s of F1 and F2 were 0.95$\mu\textrm{g}$ and 0.67$\mu\textrm{g}$, respectively. To confirm the specificity of F1 and F2 against xanthine oxidase, albumin was added to the reaction mixture. The inhibition of F1 and F2 may be due to specific binding to xanthine oxidase. The modes of their inhibitions were of mixed type with respect to xanthine as a substrate.

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Contactless Power Supply for DC Power Service in Hybrid Home Generation System (직류수용가 서비스를 위한 무접점 전원장치)

  • Kang, J.W.;Song, H.K.;Kim, J.H.;Kim, E.S.;Kim, Y.H.
    • Proceedings of the KIPE Conference
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    • 2007.07a
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    • pp.104-107
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    • 2007
  • Among the alternative energy sources, the solar energy is recognized as an important energy source and its application is increasing. Especially in future, the hybrid solar energy generation system with battery will be widely used as an independent distributed power generation system. In this paper, a solar power hybrid home generation system using a contact-less power supply (CPS) that can transfer an electric power without any mechanical contact by using magnetic coupling instead of the power transfer by directly supplying the DC power to the home electric system is proposed. The proposed system consists of a ZVS boost converter, a half bridge LLC resonant converter and contact-less transformer.

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Environmental Control Smart Farm (환경조절 스마트팜)

  • An, Sang-Hyun;Bae, Sang-Jin;Song, HwanSeok;Lee, Jeong-Won;Lee, Eun-Ser
    • Proceedings of the Korea Information Processing Society Conference
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    • 2021.11a
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    • pp.430-433
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    • 2021
  • 라즈베리파이에 아두이노를 사용해 조도, 냉각기, 열선패드 등의 센서를 사용하여 하드웨어를 구축한다. 또한 라즈베리파이에 웹 서버(PHP)를 구축하고 데이터베이스(MySQL)에 센서 값을 담아 실시간으로 웹 서버에 출력하고 제어한다. 본 논문에서는 환경이 조절되는 스마트팜의 설계 과정(UML, Use Case, DataBase 설계, 모듈 설계 등)을 포함하고 웹 서버에서 센서를 동작할 수 있게끔 만드는 과정을 설명한다.