• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1160-1163
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• 2009

Many researches showed that perceived image contrast increases as the relative surround luminance increases. However, most experiments were conducted under limited surround conditions. In this research, a psychophysical experiment was conducted to investigate the change in perceived image contrast under wide range of surround luminance up to 1820 cd/$m^2$. A large area illuminator was used as a backlight. It consists of 23 dimmable fluorescent lamps and a sheet of diffuser. The luminance could be adjusted to 7 different surround ratios: 0, 0.3, 0.56, 0.96, 2.24, 5.81, and 9.99. Results showed that perceived image contrast changes as a typical band-pass shape and the maximum contrast is found near $S_R$=1.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1209-1211
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• 2000

This paper presents a PSPICE circuit model for the simulation of both static and dynamic characteristics of fluorescent lamps. The model can by utilized for an electric ballast simulation with continuous dimming and transient mode simulation such as step dimming Characteristics of a Rosen-type piezoelectric transformer were analyzed by combining an equivalent circuit with piezoelectric equations and the relation between the characteristics and the dimension of the PT was studied.

• Journal of Information Display
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• 제13권4호
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• pp.167-177
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• 2012

Cold cathode fluorescent lamps (CCFLs) are used to provide lighting for liquid crystal displays (LCDs). This paper presents a set of guidelines for measurement characterization and design to reduce the power consumption of CCFL LCD backlight inverters and panel electronics. The proposed methods aim to reduce the backlight power consumption by fine-tuning a back-light inverter for a specific LCD, using several methods. First, the authors describe their power measurement methodology; and next, they identify different areas for tuning a backlight inverter for a given display. The experiment results showed that power savings can range from 50 to 200mW if the backlight inverter is properly tuned. This paper also proposes an optimized configuration for light-emitting device (LED) panels to reduce power loss by selecting a LED with a specific input voltage and number of cells to help minimize power loss.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제52권1호
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• pp.27-32
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• 2003

The thesis is used by PSpice circuit model to the characteristics of a fluorescent lamp modified form of he classical Cassie and Mayr equations in order to show the characteristics of HID(High-Intensity Discharge) Lamp. This is useful for applying high-frequency electric ballast for HID Lamp, and show that the result of experimentations and simulations, such as lamp rating, input voltage, high-frequency electric ballast which is using the ABM circuit model of the low pressure sodium lamp, come to the voltage and current wave.

• 산업공학
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• 제14권2호
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• pp.205-209
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• 2001

The number of tunnel has fast increased with the rapid expansion of highway network. Tunnel should be designed to provide for drivers both safety and pleasant driving conditions. In this perspective, the design for tunnel lightning is very important in order to provide its safety, pleasantness, and cost-efficienty of maintenance, all of which should be considered and analyzed for a better tunnel lighting. This paper attempts to compare the low-pressure sodium lamp, which has usually been used for tunnel lighting, with the fluorescent lamp, which we consider as an alternative for the former. In an effort to determine the number of lamps to meet the required illuminance in the tunnel, this research employs a simulation technique which would allow us to conjecture, with the aid of basic model, the life cycle cost for illumination per each tunnel. This analysis is expected to provide a basic method and related information for tunnel development and design.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1997년도 추계학술발표회논문집
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• pp.11-13
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• 1997

Abstract - An electronic starter using MOSFET has been designed to take advantage of ideal preheating and starting features which can extend the lifetime of fluorescent lamps. The preheating circuit of the developed electronic starter is consisted of four parts - afull-wave rectifier circuit, an FET switching circuit a timer circuit for the gate switching, and a circuit for end-of-life protection. The circuit is analyzed by using PSpice simulation, and is improved to give an appropriate starting-time through control of R-C time constant of the timer circuit. And the circuit is also provided with an end-of-life protection feature, which utilizes the negative resistance characteristics of a thermistor that is thermally linked to FET through a heatsink. This also protects the FET from any overheating problems. From the results of simulation it is possible to obtain an appropriate value on the starting time for proper ignition and also it is verified that the limit for resistance of the thermistor is dependant on the value of resistance is the timer circuit

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.131-134
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• 2004

Characteristics of electrodelss lamp as a load of the ballast is different compared to normal fluorescent lamp because the lamp includes the magnetics for inductive discharging process. So somewhat different modeling is necessary to make a proper power match between the lamp and ballast. Modeling of an electrodeless lamps, Endura of Osram, is presented in this paper. Simulation with a result of experiment is given for a verification of proposed model.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.313-317
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• 2004

This paper shows the structure of a control System for Fluorescent fin Dimming Ballasts. The control system is composed of phase angle controller, a transducer, many dimmable ballasts. For the implementation of the control system, We made a controller and the transducer that transform the phase angle controlled signal into the DC level. we used the conventional dimmable ballast In this ballast, dimming control is achieved by varying the switching frequency that is controlled by the external DC level. This has non-linear illumination characteristics as the dimming control. Therefore we compensate characteristics using the transducer proposed in this paper. We measured the illumination of two FL-28 lamps with dimming controller.

• 전력전자학회논문지
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• 제5권3호
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• pp.291-299
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• 2000

형광등의 수명은 형광등 안정기의 시동 시나리오와 형광등 전류의 파고율에 영향을 받는다. 본 논문에서는 특히 파고율을 주로 다루며, 파고율을 줄이기 위한 새로운 방법을 제시하고자 한다. 제안하고자 하는 방법은 펄스 주파수 변조기법(Pulse Frequency Modulation, PFM)을 이용하며, PFC(Power Factor Correction)가 만드는 50% 벨리필 전압 파형을 PFM 제어 신호로 사용한다. 본 논문에서는 제안하는 PFM 제어 기법으로 파고율을 1.7 이하로 낮출 수 있음을 모의 실험과 실험을 통해 확인하여, 제안한 기법의 타당성을 검증한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.289-292
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• 2004

전극 양단에 캐패시터를 포함한 냉음극 형광램프와 외관전극의 용량성 결합으로 동작되는 외부전극 형광램프는 동일한 전류-전압 특성을 갖는다. 냉음극 형광램프 양단에 부착하는 캐패시터의 크기는 외부전극 형광램프의 전극의 길이와 등가적으로 대응되며, 캐패시터가 클수록 그리고 외관 전극의 길이가 길수록 저 전압에서 고 휘도를 얻는다.