• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.799-802
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• 2004

In this paper, the active backlight control technology with data processing algorithm was developed in order to improve image quality for IPS-mode LCD-TV applications. The image blinking problem caused by repeatedly abrupt change of the backlight luminance was solved by algorithms-Fba(Flexible Boundary algorithm) and Cfa(Cumulative Feedback algorithm)-and the optimized number and space of backlight dimming steps based on perception. In the IPS-mode 42" TFT-LCD panel, the dynamic contrast ratio can be more than twice the typical level by means of lower block luminance and higher white luminance. Additionally, Power consumption and LCD temperature was decreased.

• Journal of IKEEE
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• v.19 no.4
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• pp.603-609
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• 2015

Thermal comfort is one of the fundamental aspects of indoor environmental quality and it is strongly related to occupant satisfaction and energy used in building. In this paper, we proposes smart comfort algorithm that save energy and provide a pleasant and comfortable environment for workers by the indoor comfort conditions(Predictive Mean Vote) detection and controlling the temperature and humidity, air flow. Simulation results, heating and cooling control of the thermal comfort control can be compared with the existing general air conditioners reduces the power of 0.5kW and indoor comfort can be maintained. Also, It showed a 49.2% improvement in the light by lighting control algorithm.

• Journal of Navigation and Port Research
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• v.34 no.10
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• pp.763-768
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• 2010

Today the light of mankind since the dawn of mankind and that they were living "lives" on the huge influence across space is a dynamic energy. Because of this, when all human beings with the light and you can feel more comfortable with a stable mind to the beauty and the pursuit of happiness is to have instincts. In this paper, a fuzzy control system using a combination of external environmental factors, respectively, the conversion of quantitative uncertainty information into the LED lighting is designed to express algorithms, available in indoor circadian control circuit was designed and fabricated LED. Factor in the external environment temperature, humidity, and light intensity values to the controller through the sensor to accept these values and the optimal values for lighting the fuzzy control algorithm is converted into human emotion to feel comfortable to express through the dimming control LED lighting.

• ETRI Journal
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• v.35 no.5
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• pp.927-930
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• 2013

We propose a visible light communication system in which the color and brightness are controllable. Pulse width modulation and variable pulse position modulation (VPPM) schemes are used to control the color and brightness, respectively. A digital algorithm to decode VPPM signals is suggested and implemented. A seamless transmission is observed in a testbed experiment under various environmental conditions. The proposed scheme can be applied to emotional-lighting-based wireless optical communication.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.73-74
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• 2013

본 논문은 LED Driver 휘도(Luminance) 제어 방식인 펄스폭 변조(PWM), 진폭변조 방식(PAM)을 조합한 스마트디밍 알고리즘에 대해 제안한다. 제안된 방식은 LED 구동 순방향 전류($I_f$)양에 따라 순방향 전압($V_f$)이 비례적으로 변화되는 특성을 이용한 것으로, LED Backlight 적용 LCM의 소비전력을 저감할 수 있다. 본 논문에서는 스마트 디밍 (CPWAM=Conditional Pulse Width Amplitude Modulation) 알고리즘에 대해 소개하고 실험을 통해 제안된 알고리즘의 타당성을 검증한다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.7
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• pp.572-575
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• 2009

In this study, we proposed WLED(White-Light Emitting Diode) driver IC for mobile applications. This IC drove WLED for mobile applications with low input voltage and high efficiency by using boost converter. The device was designed by using boost converter applied current-mode control algorithm and provided PWM(Pulse Width Modulation) & analog dimming. Designed IC consisted of bias block, drive block, control block, protection block. We confirmed this device worked well through a application PCB (Printed Circuit Board) test.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.169-172
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• 2009

Daylight responsive dimming system, which is one of the method for utilizing available daylight. continuously adjusts lighting output with an algorithm of the correlation of photosensor signal and workplane illuminance levels. This system must be related with shading systems which are to control penetrating daylight. The purpose of this research is to analyze illuminance distributions by artificial lighting in different shading systems. Lighting power is changed by 5 levels in nighttime for comparing correlation between illuminance and lighting power in different shading systems.

• Journal of the Korean Solar Energy Society
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• v.24 no.4
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• pp.35-43
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• 2004

Illuminance and luminous levels in a small office space due to daylight were calculated to analyze the impact of daylight on contrast and lighting energy savings. Computer simulations were performed for four blind conditions under a clear sky condition. The blind conditions significantly impacted the illuminance an4 luminance level. Visual performance scores were calculated according to the transfer function that uses absolute contrast between target and background surface. The blind condition that had 45 tilted angle toward ground provided good contrast and performance scores. Using a control algorithm of an automated daylight dimming control system lighting energy sayings were predicted. For all blind conditions minimum lighting energy was consumed.

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.420-422
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• 2007

Nowadays, the demand for home networking system is gradually increasing. But most of vendors use their own protocols. KNX/EIB ( European Installation Bus / Konnex) is a standard protocol approved as an European (EN 50090 - EN 13321-1) and a World-wide standard (ISO/IEC 14543). In this study, we develop on/off and dimming lighting control system using BIM. In this system, BIM communicates to micro-controller using PEI(Physical External Interface) communication. And this enables including more KNX/EIB communication objects in lighting control system, and providing lighting control algorithm. The technology in this paper can help to adapt the world-wide standards.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.289-292
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• 2008

This paper represents the electric energy saving using light control system. Without Light Control System(LCS), it is very hard to classify the amount of electric energy saving for lighting, since it is determined by the end-user's preference in times. Typical LCS has an fixed algorithm to control each light's intensity by ON/Off Control, Step Control, or Dimming Control. We have studied the electric energy saving effect in a LCS equiped building with natural lighting. The electric power consumption at the peak power consumption time with LCS reduced up to 65% of the non-controled case.