• 제목/요약/키워드: light requirement

검색결과 252건 처리시간 0.026초

인삼의 광환경과 생리반응 I.자생지. 임간 및 일복 재배에서 광경험과 광조절 방법의 변천 (Light environment and physiological response of Panax ginseng I. Experience on light in natural habitat,through cultivation under forest and artificial shade, and change of light control technique)

  • 박훈
    • Journal of Ginseng Research
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    • 제7권2호
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    • pp.172-192
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    • 1983
  • Light environment and growth of Panax ginseng In habitat and cultivation under natural shade were renewed. Grower's experiences on ginseng stand In relation to light environment were assessed. Change of shading method and grower's concepts on light requirement of ginseng plant in Korea, Manchuria and Japan was counted. Growth of wild ginseng was better under rich light. Optimum crown density index appeared to be 0.7 In natural habitat and 0.4 to 0.7 for the cultivation in forest. Change of light Intensity in forest was greatest in May and reached near to constant value (from 40% to 3% for broad leaf deciduous forest and loom 4% to 2% for pine forest). Insufficient light condition induced long and thin stem, poor flowering and seed bearing, and sequent dormancy. Relation between light and ginseng strand was not clear but light Interception with cool weather was effective. Topography and orientation of bed have been deeply considered for light environment. Panel or bark of won were used for shading in deep forest manly In Manchuria while reed blind and straw thatch were used in Korea. Kinds and number of shades material and seasonal or daily schedule have been simplified probably by labor pressure due to eulargement of plantation. Post height has been greater while width of roof, bed and ditch has changed lisle. Scientific survey in the past omitted important light control methods (complete light hardening etc) which has been practiced in specific areas. The concept and technique of light control in the past in Korea were delicate and intensive including the control of temperature and moisture. For the application of old concept in modem cultivation precise Investigation of the technique including the measurement of light, temperature and moisture is needed.

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멀티코어 이미지 프로세서 기반 열화상 이미지 시스템 개발 (Development of Thermal Image System Based Multi-Core Image Processor)

  • 차정우;한준환;박찬;김용진
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제9권2호
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    • pp.25-30
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    • 2020
  • 열화상 시스템은 물체로부터 발산되는 적외선을 영상화하여 물체를 탐지하는 장점으로 인해 군수 분야에 많이 활용되었다. 그러나 Security 시스템과 자동차 시장에 수요가 증가함에 따라 민수 분야로 활용분야가 넓어지고 있다. 기존에는 대부분 FPGA 기반으로 열화상 열상 모듈을 개발하였지만 민수 분야에 다양한 요구사항 및 범용성에 유연한 대처가 힘든 실정이다. 따라서 다양한 요구사항과 범용성을 만족하기 위한 시스템의 필요성이 대두되었다. 본 논문에서는 멀티코어 이미지 프로세서를 이용한 열화상 영상 처리 시스템을 제안한다. 제안된 시스템은 기존 FPGA 기반 시스템이 아닌 멀티코어 이미지 프로세서를 사용함으로써 범용 영상 입·출력 인터페이스 및 각종 디바이스를 지원함에 따라 다양한 요구사항과 범용성을 만족한다. 따라서 시스템 구축 시 뛰어난 접근성으로 인하여 시스템 추가/변경으로 인한 개발 비용 및 기간을 단축할 수 있다. 이러한 장점으로 다양한 고객 요구사항 만족, 개발 비용 및 시간 단축, 제품 출시일 등 다양한 이점을 얻을 것으로 기대한다.

Protective Role of Light in Heat-Induced Inhibition of Photosynthesis in Isolated Chloroplasts

  • Jun, Sung-Soo;Kim, Chang-Hoon;Hong, Young-Nam
    • Journal of Photoscience
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    • 제5권4호
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    • pp.157-162
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    • 1998
  • The effect of heat treatment in the light on the subsequent CO2 fixation was studied with isolated spinach chloroplasts to define the role of light during heat stress. The degree of inhibition in CO2 fixation after heat treatment at 35$^{\circ}C$ under full light intensity (600W/$m^2$) was same as that in the dark. However, heat treatment of isolated chloroplasts in the light manifested thylakoidal damage, which did not occur in the dark. Under weak light (10~30 W/$m^2$ ) where no thylakoidal damage occurred, the inhibition was substantially alleviated , showing protective effect of light . The inhibition caused by heat treatment in the dark or light is prevented by the addition of a few combined compounds to the medium prior to treatment. Fructose-1-6- bisphosphate(with aldolase)and ribose-5-phosphate, known to be effective combined with oxaloacetate in preventing inhibition after heat treatment in the dark were equally effective in the light even without oxaloacetate. Addition of sugar phosphate reduced the Mehler reaction, which may occur in fast rae under high light. However, the addition of bicarbnate and catalase that would remove Mehler reaction did not provide any protection, indicating that protective role of sugar phosphate is elsewhere. Furghermore, in whole plants rapid recovery from heat stress was observed in the light. The apparently lesser or equal inhibition in spite of additional thylakoidal damage under heat stres in the light and less requirement for the protection against heat treatment suggest that the inhibitory effect of heat stress is alleviated by light treatment.

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레이저 슬릿빔과 CCD 카메라를 이용한 3차원 영상인식 (3D image processing using laser slit beam and CCD camera)

  • 김동기;윤광의;강이석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.40-43
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    • 1997
  • This paper presents a 3D object recognition method for generation of 3D environmental map or obstacle recognition of mobile robots. An active light source projects a stripe pattern of light onto the object surface, while the camera observes the projected pattern from its offset point. The system consists of a laser unit and a camera on a pan/tilt device. The line segment in 2D camera image implies an object surface plane. The scaling, filtering, edge extraction, object extraction and line thinning are used for the enhancement of the light stripe image. We can get faithful depth informations of the object surface from the line segment interpretation. The performance of the proposed method has demonstrated in detail through the experiments for varies type objects. Experimental results show that the method has a good position accuracy, effectively eliminates optical noises in the image, greatly reduces memory requirement, and also greatly cut down the image processing time for the 3D object recognition compared to the conventional object recognition.

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초소형 쿼드로터 개발을 위한 기체형상 설계변경 (Design Modification of Airframe Shape for Ultra Light Quad-Rotor Development)

  • 박대진;이상철;박생진;송태훈
    • 한국항공운항학회지
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    • 제25권4호
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    • pp.44-51
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    • 2017
  • An ultra light quad-rotor is utilized in various areas for military and commercial purpose. Especially, the airframe shape is designed with various airframe size, weight and purpose. In this paper, the initial airframe shape of the quad-rotor was designed and manufactured. Flight test was conducted for the quad-rotor. The design modification of airframe shape was conducted to meet design requirement. By changing design, weight of airframe structure was reduced and payloads were placed to the best position. By reinforcing ribs and reducing vehicle's legs, the durability of airframe structure was enhanced.

Scheduling with Heterogeneous QoS Provisioning for Indoor Visible-light Communication

  • Dong, Xiaoli;Chi, Xuefen;Sun, Hongliang;Zhu, Yuhong
    • Current Optics and Photonics
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    • 제2권1호
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    • pp.39-46
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    • 2018
  • Visible-light communication (VLC) combined with advanced illumination can be expected to become an integral part of next-generation communication networks. One of the major concerns in VLC implementation is developing resource-allocation schemes in a multi-user scenario. However, the scheduling for heterogeneous quality of service (QoS) traffic has not been studied so far, for the indoor VLC downlink system. In this paper, we creatively introduce effective-bandwidth and effective-capacity theory into the multi-user scheduling (MUS) problem, to guarantee the user's statistical delay QoS. We also take account of the aggregate interference (AI) in the indoor VLC downlink system, and analyze its impact on the user-centric MUS problem for the first time. Simulations show that the AI has a nonnegligible influence on the scheduling result, and that the proposed scheduling scheme could guarantee the user's QoS requirement under the premise of ensuring sum capacity.

유전 알고리즘을 이용한 Mn4+ 활성 적색 형광체 탐색 (Search for Mn4+-Activated Red Phosphor by Genetic Algorithm)

  • 김민석;박운배
    • 한국재료학회지
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    • 제27권6호
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    • pp.312-317
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    • 2017
  • In the construction of a white LED, the region of the red emission is a very important factor. Red light emitting materials play an important role in improving the color rendering index of commercial lighting. These materials also increase the color gamut of display products. Therefore, the development of novel phosphors with red emission and the study of color tuning are actively underway to improve product quality. In the present study, heuristic algorithms were used to search for phosphors capable of increasing the color rendering index and color gamut. Using a heuristic algorithm, the phosphors that were identified were $SrGe_4O_9:Mn^{4+}$ and $BaGe_4O_9:Mn^{4+}$. Emission spectra study confirmed that these phosphors emit light in the deep red wavelength region, which can fulfill the requirement for the improvement in color rendering index and color gamut for a white LED.

Faraday 효과를 이용한 클램프형 광-전류 변류기 연구 (Study of Clamp-type Optical Current Transformer using Faraday Effect)

  • 김수길;이용욱;이병호;임용훈;홍선기
    • 조명전기설비학회논문지
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    • 제17권6호
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    • pp.60-65
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    • 2003
  • 본 논문에서는 Faraday 효과를 이용한 클램프형 구조의 광-전류 변류기 헤드 설계시에 고려해야할 조건을 이론적으로 해석하고, 이를 토대로 한 클램프형 광-전류 변류기 헤드를 제작하여, 도선에 흐르는 전류, 광의 입사각에 따른 광출력의 변화 및 감도를 측정하고 분석함으로써 전류계로서의 가능성을 입증하였다.

T-50/A-50 조종사의 인체 진동 영향성 평가 (The Evaluation of Human Vibration Effect on T-50/A-50 Pilot)

  • 문성욱;조대현;김영익
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.546-549
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    • 2004
  • The T-50/A-50 Golden Eagle was developed for a supersonic trainer and light combat aircraft. At the design stage, vibration control plans were established and applied. For cockpit vibration, crew comfort vibration level was defined by the requirement of MIL-A-8892. It is found that the T-50/A-50 meets the requirement of cockpit vibration from the flight test data analysis. This paper contains the results of cockpit vibration analysis using the flight test data and the results of human vibration analysis lot the pilot inside aircraft. The human vibration level of pilot is increased as dynamic pressure is increased and at the specific high dynamic pressure, the ride comfort indicates 'a little uncomfortable'. Overall analysis results show that the vibration level of T-50/A-50 cockpit is tolerable and not critical for pilot's comfort.

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경량전철사업 시스템엔지니어링 전산모델 검증에 관한 연구 (A Study on the Systems Engineering based Verification of a Systems Engineering Application Model for a LRT Project)

  • 한석윤;김주욱;최명성
    • 한국산학기술학회논문지
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    • 제17권7호
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    • pp.425-433
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    • 2016
  • 경량전철시스템의 건설은 노선당 수천억 원에서 조 단위의 건설비가 소요되는 대형 복합인프라 사업으로, 건설된 시스템은 장기간 운영되기 때문에 생명주기관점에서 사업을 추진하는 것이 매우 중요하다. 시스템엔지니어링은 고객의 요구를 성공적으로 구현하는 수단 및 방법론으로 경량전철사업과 같은 대형 사업에 매우 유용하다. 이러한 시스템엔지니어링 접근법을 경량전철사업에 적용하기 위해 개발된 전산모델 SELRT(Systems Engineering application model for Light Rail Transit project)가 현장에서 활용되기 위해서는 모델에 대한 검증이 필요하다. 시스템엔지니어링에서의 검증은 시스템요구사항을 만족하였음을 확인하는 것이다. 따라서 본 논문에서는 시스템엔지니어링 방법론에 따라 검증 절차와 검증 아키텍처를 제시하고, 이에 따라 시스템요구사항을 식별하였다. 또한 시스템요구사항을 검증하기 위해 국제 표준규격 등 참조규격을 참고하여 검증요구사항 및 검증항목과 검증기준을 도출하였으며, 검증절차에 따라 SELRT를 시연하고 결과를 검증요구사항과 비교하였다. 그 결과 시스템요구사항과 검증요구사항의 추적성, 검증요구사항별 검증방법, 전산도구의 시연결과가 상호 연결되고, 최초요구사항이 SELRT에 명확히 구현되었음을 확인할 수 있어, 제안된 방법이 SELRT 검증에 유효하며, SELRT도 경량전철사업현장에서 활용될 수 있음이 확인되었다.