• 제목/요약/키워드: light requirement

검색결과 252건 처리시간 0.032초

고해상도 광학영상장비 반사경 구조해석 (Mirror Structure Analysis of High Resolution Optical Imaging Payload)

  • 권우근;김광로;이영신
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.462-467
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    • 2003
  • For the Space-borne optical imaging payload system design, light weighting and moderate stiffness of mirror and/or mirror fixation device is very important aspects. The front surface of mirror is regulated by optical performance requirement, but the shape of backplate of mirror is to be optimised while satisfing the required stiffness and weight. According to the results, the best shape of backplate cell is triangular. And also related geometric dimensions and the optimised mounting point of MFD(Mirror Fixation Device) is presented. Finally, natural frequencies and shpaes of mirror structure are analysed.

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데크 크레인용 페데스탈의 구조해석 및 최적화 (Structural Analysis and Optimization of a Pedestal for Deck Crane)

  • 최동환;이권희
    • 한국기계가공학회지
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    • 제11권1호
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    • pp.95-100
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    • 2012
  • A deck crane is installed on the deck of a ship when there is no adequate facility for loading and unloading in dock or harbor. Deck cranes in Korea have been imported from abroad, and the import-substitution effect will arise if its production can be localized. Now, it is required to suggest the structural design of a deck crane that meet the domestic criterion, considering loading condition. In this study, the structural analysis of a pedestal in the deck crane was peformed by finite element method to investigate the strength requirement. In addition, the structural design of a pedestal was suggested by using ANSYS and VisualDOC. The optimized structure of a pedestal was determined, considering lightweight design.

한글문자 인식을 위한 수정3차 위상SDF필터 (Modified Ternary Phase-Only SDF Filter for Korean Character Recognition)

  • 도양회;김정우;정신일;하영호;김수중
    • 대한전자공학회논문지
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    • 제26권8호
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    • pp.1262-1269
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    • 1989
  • For the efficient recognition of Korean characters, a modified ternary phase-only synthetic discriminanty function filter(MTPOF-SDF) is proposed. MTPOF-SDF can not only discriminate the true class patterns and the similar, symmetric, or patially included false ones but also recognize the diverse variations in true class patterns due to combinatorial form as the same ones. And scale and rotation-invariant recognition is achieved. To preserve the features of the characters, phase information should be used. And to contsrol phase information easily, ternary quantization of the phase is preferred. Also low resolution requirement is achieved for compatibility with low resulution devices such as spatial light modulators.

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미세 트랙킹을 위한 마이크로미러 액튜에이터의 구동 특성 (ACTUATION CHARACTERISTICS OF A MICROMIRROR FOR FINE-TRACKING)

  • 이영주;부종욱;김수경
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.1521-1527
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    • 2000
  • A micromirror actuated by piezoelectric unimorph cantilevers is proposed as a tine-tracking device for high-density optical data storage. Bending motions of the metal/PZT/metal unimorphs translate an integrated micromirror along the out-of-plane vertical direction. The micromirror alters the optical path of the incident laser beam and linearly steers the reflected laser beam by its out-of-plane parallel actuation. Numerical analysis shows that the actuated micromirror can satisfy the tracking speed imposed by the requirement on the access time for the high-density optical data storage up to few tens Gbitlin2 owing to the light mass of the micromirror. In this paper, preliminary characteristics of the micro-machined PZT actuated micromirror (PAM) are reported. Only a 360 nm-thick PZT film deposited by sol-gel process shows both good electrical and mechanical characteristics for the fine-tracking actuator. The micromirror can be easily actuated up to several micrometers under low voltage operation condition well below 10 volts.

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직렬 연결된 두개의 트랜스포머를 갖는 새로운 위상천이 풀 브릿지 컨버터 (A New Phase Shift Full Bridge Converter with Serially Connected Two Transformers)

  • 구관본;김태성;문건우;윤명중
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2002년도 전력전자학술대회 논문집
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    • pp.370-373
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    • 2002
  • A new phase shift full bridge converter(PSFB) with serially connected two transformers is proposed. It is well suited for applications in the communication equipment of a few hundred watts. The main features of the proposed converter are a wide input voltage range, an easiness to meet the requirement for zero voltage switching (ZVS) condition at a light load, and a small output voltage ripple. Furthermore, it features high power density since serially connected two transformers can replace both a main transformer and an output inductor. A mode analysis and experimental results are presented to verify the validity of the proposed converter.

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COMS EAST/WEST STATIONKEEPING FUEL CONUMPTION CONSIDERING MANDATORY OBSERVATION TIME SOLOTS OF OPTICAL PAYLOADS

  • Park, Bong-Kyu;Lee, Sang-Cherl;Yang, Koon-Ho
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.166-170
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    • 2007
  • This paper discusses stationkeeping of COMS which accommodates two optical payloads. In order to provide good quality images to the users, the east/west stationkeeping which is strong perturbing sources shall be performed outside of mandatory observation time slots asked by users. If the east/west stationkeeping time is resulted inside of the mandatory time slots, it shall be shifted in order to be performed outside of mandatory time slot, or a new stationkeeping shall be planned. This constraint is expected to ask additional fuel consumption in comparison with tradition stationkeeping. This paper analyzes the impact of mandatory time slots to the stationkeeping fuel consumption. Orbit simulations have been conducted to determine validity of given constraints in the light of fuel requirement and stationkeeping accuracy.

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주요잡초 종자의 발아시 산소 요구도 (Oxygen Requirement for Germination of Weed Seeds)

  • 김소연
    • 한국작물학회지
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    • 제23권2호
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    • pp.145-149
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    • 1978
  • 산소농도에 따른 질소, 산소혼합 gas중에서 7종의 잡초의 발아시험을 실시발아시의 산소요구도를 조사하였다. 1, 같은 잡초라도 종자의 전역에 따라 발아시의 산소요구도가 다른 경우가 있다. 2. 초종간의 발아시 산소요구도는 ヒメイヌボエ 여뀌>사마귀풀>물피>돌피>올챙고랭이>물달개비로서 올챙고랭이와 물달개비는 공기중 보다도 산소농도가 낮은 조건에서 발아가 양호 하였다. .3. 산소농도가 어느 농도보다도 저하하게 되면 유아의 신장 엽색의 발현이라던가 발근이 조해되었다.

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HandButton: Gesture Recognition of Transceiver-free Object by Using Wireless Networks

  • Zhang, Dian;Zheng, Weiling
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권2호
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    • pp.787-806
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    • 2016
  • Traditional radio-based gesture recognition approaches usually require the target to carry a device (e.g., an EMG sensor or an accelerometer sensor). However, such requirement cannot be satisfied in many applications. For example, in smart home, users want to control the light on/off by some specific hand gesture, without finding and pressing the button especially in dark area. They will not carry any device in this scenario. To overcome this drawback, in this paper, we propose three algorithms able to recognize the target gesture (mainly the human hand gesture) without carrying any device, based on just Radio Signal Strength Indicator (RSSI). Our platform utilizes only 6 telosB sensor nodes with a very easy deployment. Experiment results show that the successful recognition radio can reach around 80% in our system.

Trichophyton tonsurans의 진균학적 성상 (Mycologic Characteristics of Trichophyton tonsurans)

  • 방용준;김쌍용;신두만
    • 대한임상검사과학회지
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    • 제36권1호
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    • pp.7-12
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    • 2004
  • Trichophyton(T.) tonsurans has been identified for the first time in Korea in 1995 and has been increasing in number of reported in wrestlers, in judo players, and in korean - style wrestlers. Author tried mycological studies with T. tonsurans is isolated in Daegu Korea. The results are as follows: All 16 strains of T. tonsurans tested for nutritional requirement, showed strongly stimulated growth by thiamine, mild to moderate growth on casamino acid agar, poor growth on ammonium nitrates base agar. All 16 strains of T. tonsurans tested showed positive results for hair perforation and urease test. Gross findings of T. tonsurans showed that fine granular surface with light yellow hue or white color and mahogany brown color on the reverse side. Microscopic findings showed that septated hyphae, chlamydoconidia and microcondia. Microconidia were characteristic in their arrangerment and shape : round or oval shaped microconidia laterally to hyphae, some were match - head like terminal swelling.

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High Luminance $Zn_2SiO_4:Mn$ Phosphors Prepared by Homogeneous Precipitation Method

  • Sohn, Kee-Sun;Choi, Yoon-Young;Jung, Ha-Kyun;Park, Hee-Dong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.31-32
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    • 2000
  • $Zn_2SiO_4:Mn$ phosphors have been recently spotlighted as a green component for plasma TV application. Commercial phosphors such as P1 and P39 have been known to be a very efficient green light emitter for lamp and CRT application. Unfortunately, such commercial phosphors are not suitable for the plasma TV application as both the emission intensity and the decay time do not meet the requirement for plasma TV. The present investigation aims at improving the existing $Zn_2SiO_4:Mn$ phosphors for the purpose of adapting them to PDP application.

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