• 제목/요약/키워드: Huh Jun

검색결과 447건 처리시간 0.026초

HIGH RESOLUTION IMAGE ACQUISITION MODE USING PANCHROMATIC REDUNDANT CHANNEL

  • Chang, Young-Jun;Kong, Jong-Pil;Huh, Haeng-Pal;Kim, Young-Sun;Park, Jong-Uk
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.800-803
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    • 2006
  • The Space-borne electro-optical camera system, like KOMPSAT has panchromatic redundant image channel as well as primary channel in order to increase reliability of satellite system. In most case redundant channel never been used during the whole mission period. Staggered array configuration using redundant image channel and new operation mode proposed which operates primary and redundant channel simultaneously. Without new hardware design, fast electronics and system complexity, we can get 1.414 times more fine GSD image of original system and aliasing effect which corrupt high frequency information of image can be minimized. To get the more efficiency from staggered array configuration, we introduce masked pixel CCD.

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유압 구동계 에너지 재생 브레이크를 적용한 자동차 테일게이트 개폐장치에 대한 동특성 해석 (Dynamic Analysis on the Tail Gate System for Vehicle with the Energy Regenerative Brake of Hydraulic Driven Systems)

  • 최순우;허준영
    • 유공압시스템학회논문집
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    • 제7권2호
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    • pp.19-26
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    • 2010
  • The typical trunk lid system for vehicle is composed of a hinge having 4-bar link and gas lifter. Here, the energy regenerative brake of hydraulic driven systems is applied to the tail gate system for vehicle and removed the gas lifter. The new tail gate system is composed of a hydraulic pump by electric motor, a hydraulic motor, four check valves, an accumulator, a relief valve and a directional control valve. The dynamic characteristics of the hydraulic motor system, such as the surge pressure and response time, are investigated in both brake action and acceleration action. The capacity selection method of accumulator by mathematical model is based upon trial and error approach and computer simulation by AMEsim software is carried out.

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단거리용 무선 광통신 트랜시버의 제작 및 성능평가 (Fabrication and evaluation of the short-range optical wireless transceiver)

  • 정희성;허형준;김희수;곽노민;조규만;최영완;조규섭
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2003년도 하계학술대회
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    • pp.180-182
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    • 2003
  • 200m 이하의 전송거리를 가지며 송신기와 수신기가 일체화된 단거리 무선 광통신용 트랜시버를 제작하고, 그 성능을 평가하였다. 이러한 단거리 무선 광통신 트랜시버는 가격이 저렴한 저출력의 레이저를 광원으로 사용할 수 있고, 능동 정렬이 필요 없을 뿐만 아니라, 작은 구경의 렌즈를 사용할 수 있기 때문에 크기가 작고, 가벼우며, 설치가 쉽다는 장점을 가진다. 특히 패키징 개념을 사용하여 송신기와 수신기의 광축을 미리 수평으로 정렬한 후 영구고정함으로서 기계공작이 최소화되고, 송신기 부분의 정렬만으로 수신기가 정렬되므로 링크의 정렬이 매우 간단하며, 저렴한 무선 광통신 시스템의 구성이 가능하다.

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단거리용 무선 광통신 모듈의 링크 설치 결과 및 환경 요인 분석 (The Environmental Influence on the Performance of Short Range Free Space Communication Link)

  • 허형준;김희수;곽노민;조규만;정희성;최영완;조규섭
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2003년도 하계학술대회
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    • pp.379-381
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    • 2003
  • 155Mbps 단거리용 무선 광통신 모듈을 120m 의 짧은 거리에 설치하였다. 그 결과 99.98% 이상의 error free availability와 99.99% 이상의 severely error free second rating을 가졌다. error의 요인을 분석한 결과 30mm/h 정도의 비에도 크게 영향을 받지 않음을 알 수 있었다. 맑은 날에도 error가 발생하였는데 그 원인은 날아가는 새와 같은 물체가 링크를 가리기 때문이었다.

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Client Technology on a Server for Mobile Cloud

  • ;;;이준형;허의남
    • 정보와 통신
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    • 제28권10호
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    • pp.3-10
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    • 2011
  • The increasing ubiquity of wireless networks and decreasing cost of hardware is fueling a proliferation of mobile devices. These devices are enabling a new revolution in mobile technology, not only running locally on them, but running on cloud as a service as well. From web browsing, email, or video conferencing, presentations to movie and music entertainment or games, multimedia applications, mobile cloud enables providing such diverse applications. Many technologies have been designed to address the limited hardware and performance in thin client PC. However, with the assorted network and graphic condition, those proposed technologies is obligated to alter aim to adapt mobile cloud. In this paper, we provide a survey of client technology on a Server that can be sufficed the requirements of Mobile Cloud. We also analyze each technology and classify with its individual difficulties and challenges.

소아에서 복강경을 이용한 메켈씨 게실 절제술 (Laparoscopic Meckel's Diverticulectomy in Children)

  • 한석주;김준영;허정욱;한애리;황의호
    • Advances in pediatric surgery
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    • 제7권2호
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    • pp.157-161
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    • 2001
  • Meckel's diverticulum is one of the common causes of gastrointestinal bleeding in the pediatric patient requiring laparotomy. Two children with Meckel's diverticulum have been successfully treated by laparoscopic excision. Both patients recovered without incident and were discharged at 3 and 5 days after surgery. The authors believe that laparoscopic diverticulectomy is a safe, effective. and minimal invasive treatment of Meckel's diverticulum in children.

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일반 점검사진에서 교량의 정적 변위 추출을 위한 영상처리기법 (Image Processing Technique for Measuring the Static Displacement of Bridges from General Inspection Photograph)

  • 조준상;허영
    • 대한토목학회논문집
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    • 제31권3A호
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    • pp.173-180
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    • 2011
  • 본 연구에서는 일반 점검용 사진목적으로 촬영되어 저장되어 있는 데이터베이스(Data Base)의 이미지에서 목표물의 색, 형태 및 공간이동 정보를 수치 해석적으로 접근하여 교량의 변위를 산출하는 비접촉, 비타켓 방식의 영상처리기법(Image Processing Technique)을 제안하였다. 수치해석 및 모형실험을 통하여, 일반 교량점검 사진에서 교량의 변위를 추출하는 방법으로 타당함을 검증하였다. 이를 활용하여 공용중인 교량의 온도에 의해 변화하는 교량의 정적 거동특성을 파악할 수 있다.

Temperature control of a batch PMMA polymerization reactor using adaptive predictive control algorithm

  • Huh, Yun-Jun;Ahn, Sung-Mo;Rhee, Hyun-Ku
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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    • pp.51-55
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    • 1995
  • An adaptive unified predictive control (UPC) algorithm is applied to a batch polymerization reactor for poly(methyl methancrylate) (PMMA) and the effects of controller parameters are investigated. Computational studies are performed for a batch polymerization system model developed in this study. A transfer function in parametric form is estimated by recursive least squares (RLS) method, and the UPC algorithm is implemented to control the reactor temperature on the basis of this transfer function. The adaptive unified predictive controller shows a better performance than the PID controller for tracking set point changes, especially in the latter part of reaction course when gel effect becomes significant. Various performance can be acquired by selecting adequate values for parameters of the adaptive unified predictive controller; in other words, the optimal set of parameters exists for a given set of reaction conditions and control objective.

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Neoparamoeba sp. Infection on Gills of Olive Flounder, Paralichthys olivaceus in Korea

  • Kim, Hyoung-Jun;Cho, Jae-Bum;Lee, Mu-Kun;Huh, Min-Do;Kim, Ki-Hong
    • 한국어병학회지
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    • 제18권2호
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    • pp.125-131
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    • 2005
  • Amoebic gill disease of flounder, Paralichthys olivaceus was diagnosed at commerical culture facility in South Korea. The amoeba was identified as a species of the genus Neoparamoeba based on the morpholgical characteristics of trophozoites. Transmisson electron microscopy revealed the presence of a symbiotic organism, parasome in the cytoplasm and dense glycocalyx on the surface of the trophozoites. They lacked the boat-shaped microscales on the surface and contained numerous vacuoles and channels, mitochondria in the cytoplasm. Colonization of amoebae on gill tissue elicited extensive fusion and hyperplasia of gill lamella.