• 제목/요약/키워드: light signal

검색결과 1,263건 처리시간 0.024초

경량전철 기술개발 종합시험을 위한 시험선로 건설 사례 (Construct Test Line of Light Rail Transit for Overall Test and Commissioning)

  • 이안호;이덕영
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.1118-1123
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    • 2004
  • Launched in 1999 and funded by the Korean government, the R&D project of developing the. light train system technology is finally wrapped up to produce its prototype train prototype and all the research activities on signal, communication, power supply third rail Type and infra-structure have been completed. In an attempt to verify the usability of the system through an actual testing and as a preliminary step to the application of the system to overall light train construction projects to be implemented in different cities in Korea, testing lines are under construction now. Here we'd like to introduce people to the general overview of the test line construction and interface found in the process of project.

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LCTV 공간 광 변조기를 이용한 비선형 홀로그래픽 연상메모리의 광학적 실현 (Optical Implementation of Nonlinear Holographic Associative Memory using LCTV Spatial Light Modulator)

  • 황의인;이승현;이우상;김은수
    • 대한전자공학회논문지
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    • 제26권11호
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    • pp.1872-1879
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    • 1989
  • In this paper, we implement optical holographic associative memory based on the two-dimensional neural network model by using commercial LCTV as a spatial light modulator. The system consists of the simple Vander Lugt correlator utilizing plane Fourier hologram and the pinhole array. The associated output signal is detected on a two-dimensional CCD camera and electronically thresholded and fed back to the input plane of the system. Through the experimental demonstration of nonlinear holographic associative memory, it is suggested that commercial LCTV can be used as a new coherent spatial light modurator.

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A Novel Driving Algorithm for Reducing Dynamic False Contour in PDPs

  • Yoon, Seok-Jeong;Choi, Sang-Yoon;Lee, Seung-Yong;Choi, Byong-Deok;Kwon, Oh-Kyong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1269-1272
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    • 2005
  • We propose a simple and efficient driving algorithm to reduce Dynamic False Contour(DFC) in Plasma Display Panels(PDPs) by using both accumulation and combination of light emission periods. Although the accumulative way of light emission in sustain period is regarded as more effective than combinational way to reduce DFC, it takes much addressing time to express high gray-scale. Therefore, we combine accumulative and combinational light emission methods to reduce DFC. In the proposed method, one TV field (16.7ms) is composed of four combinational subfields for expressing small gray scales and fifteen accumulative subfields for large gray scales. In addition, we use some Graphic Signal Processing(GSP) algorithm to get more natural images by reducing DFC.

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A Comparative Study Between Light Extinction and Direct Sampling Methods for Measuring Volume Fractions of Twin-Hole Sprays Using Tomographic Reconstruction

  • Lee, Choong-Hoon
    • Journal of Mechanical Science and Technology
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    • 제17권12호
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    • pp.1986-1993
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    • 2003
  • The spatially resolved spray volume fractions from both line-of-sight data of direct measuring cells and a laser diffraction particle analyzer (LDPA) are tomographically reconstructed by the Convolution Fourier transformation, respectively. Asymmetric sprays generated from a twin-hole injector are tested with 12 equiangular projections of measurements. For each projection angle, a line-of-sight integrated injection rate was measured using a direct sampling method and also a liquid volume fraction from a set of line-of-sight Fraunhofer diffraction measurements was measured using a light extinction method. Interpolated data between the projection angles effectively increase the number of projections, significantly enhancing the signal-to-noise level in the reconstructed data. The reconstructed volume fractions from the direct sampling cells were used as reference data for evaluating the accuracy of the volume fractions from the LDPA.

반도체 레이저의 광 주입을 이용한 혼동 통신망의 암호화 기법 분석 (Analyses of Encryption Method for Chaos Communication Using Optical Injection Locked Semiconductor Lasers)

  • 김정태
    • 한국정보통신학회논문지
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    • 제9권4호
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    • pp.811-815
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    • 2005
  • We theoretically studied synchronization of chaotic oscillation in semiconductor lasers with chaotic light injection feed-back induced chaotic light generated from a master semiconductor laser was injected into a solitary slave semiconductor laser. The slave laser subsequently exhibited synchronized chaotic output for a wide parameter range with strong injection and frequency detuning within the injection locking scheme. We also analytically examined chaos synchronization based on a linear stability analysis from the view point of synchronization based on a linear stability analysis from the view point of modulation response of injection locked semiconductor lasers to chaotic light signal.

비정질 셀레늄 디지털 X선 검출기에 대한 잔류 전하 제거 기술 (Latent Charge Erasing Technique for a-Se Digital X-ray Detector)

  • 강상식;최장용;박치군;조진욱;문치웅;최흥국;남상희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.505-508
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    • 2001
  • Currently there is much interested in removing latent charge that is caused to latent image effect and blurring of obtained image as well as reduction of x-ray conversion efficiency in digital radiography system. To remove latent charge a-Se film is irradiated by light with 3500 lux using halogen lamp and optical fiber. We measured dark current and photosensitivity to analyze removing effect of latent charge, then compared with and without light erasing method. The reduction of measured signal due to latent charge effect was 32.5 %, and the removal effect of latent charge by using light erase method was its 95.5 %.

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시분할 다중 전송방식을 이용한 원격 조명제어 설계 (Design of a Remote Lighting Control System Using Time Division Multiplex Transmission)

  • 정성재;김일환
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.33-33
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    • 2000
  • In this paper a new distributive control system for BA(Building Automation ) lighting control used on general microprocessors is presented. For optimal lighting control and saving energy, The system have to control the group and pattern lighting control as well as individual light control at one time. Tn this paper, This functions are accomplished with low-cost and simple microprocessor. A plurality of modulated light control terminals are connected to the central control unit through a pair of power line. This power line provide both power and signal to the each terminal and the data is transmitted through cyclic time division multiplex transmission. With this structure a low-cost distributive control system for lighting applications has been achieved, allowing energy and maintenance saving and reliability increase of the light control system.

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시동 배기가스 점화기술을 이용한 촉매의 예열시간 단축 (Fast Light-Off of Catalyst using Cranking Exhaust Gas Ignition)

  • 조용석;엄인용;이윤석;김득상;김충식;천준영;최진욱
    • 한국자동차공학회논문집
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    • 제9권2호
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    • pp.43-49
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    • 2001
  • In order to satisfy the ULEV emissions regulation, fast light-off of a catalyst is essential for reduction of HC and CO emissions during the cold start. Cranking Exhaust Gas Ignition(CEGI) method developed in this study showed that the catalyst reaches the light-off temperature in a few seconds. The CEGI stops the ignition signal for a few seconds during the cranking period, so the unburned fuel-air mixture bypasses the combustion chamber and flows through the exhaust manifold. When the unburned mixture reaches two glow plugs installed upstream of the catalyst, it burns and releases the thermal energy to heat up the catalyst, In the FTP-75 vehicle tests, the CEGI showed that the exhaust emissions reduced by 47.7% for THC and by 88.6% for CO in the cold-transient phase of the test.

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냉시동시 촉매의 예열시간 단축에 관한 연구 (A Study for Fast Light-Off of a Catalyst During Cold Start)

  • 조용석;이윤석
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 1998년도 제17회 KOSCI SYMPOSIUM 논문집
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    • pp.69-77
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    • 1998
  • In order to meet the stringent emission regulations, fast light-off of a catalyst is essential to reduce the HC and CO emissions during cold start. Cranking Exhaust Gas Ignition (CEGI) method developed in this study showed that the catalyst reaches the light-off temperature in a few seconds after cold start. The CEGI system cuts off the ignition signal for a few seconds during the cranking period. so the unburned fuel-air mixture bypasses the combustion chamber and flows through the exhaust manifold. When the unburned mixture reaches two glow plugs installed upstream of the catalyst, it burns and releases the thermal energy to heat up the catalyst. Results from the FTP-75 tests showed that the exhaust emissions with the CEGI reduced by 47.7% for THC and by 88.6% for CO in the cold-transient phase of the test.

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Rolling Shutter CMOS 센서 기반 가시광 통신 시스템의 성능 분석 (Performance Analysis of Visible Light Communication System Using Rolling Shutter CMOS Sensor)

  • 트렁홉도;유명식
    • 한국통신학회논문지
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    • 제40권10호
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    • pp.2065-2067
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    • 2015
  • 본 논문에서는 Rolling Shutter CMOS 센서를 이용한 가시광 통신 시스템의 성능을 분석하였다. 성능분석을 위하여 ISI (Inter-symbol Interference)가 가시광통신에 미치는 영향을 분석하였다. 모의실험을 통하여 분석결과의 타당성을 검증하였다.