• Animal cells and systems
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• 제9권3호
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• pp.139-144
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• 2005

The attractant (orange light) or repellent (white light) signal is transmitted from SRI (Sensory Rhodopsin I) via protein-protein interaction with its transducer Htrl (Halobacterial Transducer for Sensory Rhodopsin I) which in turn controls a cytoplasmic phospho-transfer pathway that modulates flagella motor switching in Halobacterium salinarum. Some mutations in both SRI and Htrl showed an unusual mutant phenotype called inverted signaling, in which the cell produces a repellent response to normally attractant light. Twelve mutations at the Glutamate 56 (E56) position in the second transmembrane helix of Htrl were introduced by site-specific random mutagenesis. Almost all E56 mutants showed orange-light inverted responses in pH and temperature-dependent manners except E56D and E56Y. Except for these two mutants, all mutants accelerated the $S_{373}$ decay compared to wild-type at $18^{\circ}C$. This supported that there is an interaction between SRI and the second transmembrane of Htrl. Also a structural model of Htrl based on the Tar crystal structure and the secondary structure prediction program proposed the E56 residue to be in the middle of the proton channel. The most important observation is that the E56 mutant provides the evidence that this residue is very sensitive for signal relay, which can be explained by the open and closed conformations of the channel (A and R conformations) in SRI, as was postulated by the unified conformational shuttling model for transport and signaling.

• Journal of Multimedia Information System
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• 제6권4호
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• pp.329-332
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• 2019

Recently, smart lighting systems are the combination between sensors and lights. These systems turn on/off and adjust the brightness of lights based on the motion of object and the brightness of environment. These systems are often applied in places such as buildings, rooms, garages and parking lot. However, these lighting systems are controlled by lighting sensors, motion sensors based on illumination environment and motion detection. In this paper, we propose an automatic lighting control system using one single camera for buildings, rooms and garages. The proposed system is one integration the results of digital image processing as motion detection, hand gesture detection to control and dim the lighting system. The experimental results showed that the proposed system work very well and could consider to apply for automatic lighting spaces.

• Transactions on Electrical and Electronic Materials
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• 제8권4호
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• pp.166-169
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• 2007

In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold type display mode, we made an experiment to drive TN-LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by counting between on time and off time for video signal input during 1 frame (16.7 ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by CCFL blinking drive and TN-LCD overdriving. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

• Current Optics and Photonics
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• 제2권6호
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• pp.532-539
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• 2018

Multiple LED arrays can be utilized in visible-light communication (VLC) to improve communication efficiency, while maintaining smart illumination functionality through dimming control. This paper proposes a modulation scheme called "Spatial Intensity Modulation" (SIM), where the effective number of turned-on LEDs is employed for data modulation and dimming control in VLC systems. Unlike the conventional pulse-amplitude modulation (PAM), symbol intensity levels are not determined by the amplitude levels of a VLC signal from each LED, but by counting the number of turned-on LEDs, illuminating with a single amplitude level. Because the intensity of a SIM symbol and the target dimming level are determined solely in the spatial domain, the problems of conventional PAM-based VLC and related MIMO VLC schemes, such as unstable dimming control, non uniform illumination functionality, and burdens of channel prediction, can be solved. By varying the number and formation of turned-on LEDs around the target dimming level in time, the proposed SIM scheme guarantees homogeneous illumination over a target area. An analysis of the dimming capacity, which is the achievable communication rate under the target dimming level in VLC, is provided by deriving the turn-on probability to maximize the entropy of the SIM-based VLC system. In addition, a practical design of dimmable SIM scheme applying the multilevel inverse source coding (MISC) method is proposed. The simulation results under a range of parameters provide baseline data to verify the performance of the proposed dimmable SIM scheme and applications in real systems.

• 한국산학기술학회논문지
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• 제21권6호
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• pp.296-301
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• 2020

국내 신호등은 2색등, 3색등, 4색등의 신호체계를 적용하고 있다. 2색등은 적색•녹색 등화로 주로 횡단보도에서 사용되며 3색등은 적색•황색•녹색(녹색화살표)등화로 T자형 교차로, 4색등화 표시는 적색•황색•녹색화살표•녹색으로 일반적인 교차로에서 사용되고 있다. 교차로에 진입하는 운전자는 딜레마 존 영역에서 교차로 진입 또는 정지선에 정지 판단을 해야 한다. 교차로 진입 전 딜레마 존에서 운전자는 교차로 폭, 차량속도, 인지반응시간, 기준 황색신호 시간에 따라 교차로 통과 또는 정지선에 정지, 과속차량, 꼬리물기, 끼어들기, 신호위반 차량 등 많은 정보를 수집 판단하고 있다. 본 논문은 교차로 3,4색 신호등의 기준 황색신호 시간과 교차로 통과 속도를 50km/h, 60km/h하향 조정에 따른 딜레마 존 영역 길이 변화가 황색신호 시간에 영향을 줄 수 있음을 제시한다. 이러한 영향에 따른 황색신호 시간은 0.1~2.3초 증가함을 알 수 있었으며 딜레마 존 영역도 1.22~26[m] 증가함을 알 수 있었다. 교차로 사고 감소를 위해 딜레마 존의 운전자에게 빠른 판단할 수 있도록 직진(3색,4색) 녹색신호의 잔여시간을 표시함으로써 교차로 통행에 발생하는 교통사고를 줄이는 방안을 제시하며, 심야시간에 운영되어지는 교차로 점멸신호에 진입하는 차량에 적색(LED 손바닥)신호와 좌회전 녹색 화살표 신호를 교차 점멸함으로 안전한 진입 방안을 제시하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.160-163
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• 2004

A passive lossless turn-on/turn-off snubber network is proposed for the boost PWM converter. Previous AC/DC PFC Boost Converter perceives feed forward signal of output for average current-mode control. Previous Boost Convertor, the Quantity of input current will be decreased by the decrease of output current in light load, and also Power factor comes to be decreased. Also the efficiency of converter will be decreased by the decrease of power factor. The proposed converter presents the good PFC, low line current harmonic distortions and tight output voltage regulations using energy recovery circuit. All of the semiconductor devices in the converter are turned on under exact or near zero voltage switching(ZVS). No additional voltage and current stresses on the main switch and main diode occur. To show the superiority of this converter is verified through the experiment with a 640W, 100kHz prototype converter.

• 한국위성정보통신학회논문지
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• 제7권3호
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• pp.145-148
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• 2012

최근의 TV용 TFT-LCD에서는 동화상에서의 잔상발생을 줄이는 것이 중요한 기술적 요구사항이 되었다. Single-LVDS 신호체계에서 3D를 대응하기 위한 Quad Signal Package 까지 진화하면서 보다 빠른 신호를 정해진 시간안에 처리해야 하는 문제가 발생하고 있으며, 이러한 특성을 구현하기 위해서 잔상효과가 없는 Backlight에 대한 연구가 활발히 진행되고 있다. 본 연구에서는 점멸방식의 Backlight 를 사용하여, 1Frame의 시간안에 이 동작이 가능하게 구현하는 것을 목표로 삼았으며, 광원으로는 기존의 냉음극관램프를 사용하였다. 통상 냉음극관램프는 주 발광파장대를 담당하는 녹색의 잔광시간이 길어서 위와 같은 특성을 구현하기에 어려움이 있었으나, 본 연구에서는 단잔광 특성을 가지는 녹색 및 적색 형광체를 적용한 냉음극관램프를 적용하여, 1Video Frame의 시간안에 점멸동작이 가능한 백라이트를 제작하였으며, 이를 사용하여, 동화상에서 비약적인 잔상 해결 효과를 확인할 수 있었다.

• 한국도로학회논문집
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• 제10권4호
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• pp.199-211
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• 2008

본 연구는 청주시 4지 신호교차로에서 발생한 측면직각 충돌사고를 다루고 있다. 연구의 목적은 측면직각 충돌사고의 특성을 분석하고, 순서형 프로빗 모형을 이용하여 사고의 심각도에 영향을 주는 사고요인을 파악하는 것이다. 이를 위해 본 연구는 2004년과 2005년의 2년간 181개 교차로에서 발생한 580건의 측면직각 충돌사고 자료를 이용한다. 사고특성 분석결과, 야간과 직진 중에 가장 많은 교통사고가 발생하였으며, 주된 원인은 신호위반으로 밝혀졌다. 사고심각도 모형개발의 주요결과는 다음과 같다. 첫째, 모형의 적합도를 나타내는 우도비(${\rho}^2$)값은 0.094이며, 변수의 적합성을 나타내는 t-ratio 값은 모두 통계적으로 유의한 것으로 분석되었다. 둘째, 측면직각 충돌사고의 심각도에 영향을 미치는 변수로는 부도로 교통량, 부도로 차로수, 주도로 좌회전차로, 주도로 좌회전신호유무, 주도로 황색신호시간, 교차각, 주도로 부도로 제한속도가 선정되었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권9호
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• pp.407-413
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• 2005

The optical current transformer was developed for 170 kV GIS using optical fiber. The sensor optimized on the optical CT was wound 3 turns and twisted 4 times per a turn at the pipe with a diameter of 130 m. To optimize the optical CT, the output signal was measured according to the setting angle of polarizer and analyzer, The asymmetry and distortion of the output signals were improved when the parallel polarized light was incident to the fiber sensor and under the angle of analyzer was $45^{o}$. The measurement error for the linearity was only $\pm{0.42}\;\%$ to 1,000 A in the case of reflection type.

• International Journal of Internet, Broadcasting and Communication
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• 제9권2호
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• pp.70-77
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• 2017

Where there are all the flowers, the songs of all kinds of insects and birds are put in, the sunshine and shadows flicker The forest through which the water sound flows is an optimum resting space. All living creatures in these spaces will awaken the five senses of humans and perhaps turn the sensibility index (EQ). The forest meditation in the forest, which can be an optimal shelter for the people who need it, needs to feel the reverence of nature, to refine emotions, to be a self-reflection, to have a mind to respect, Have an important meaning. In this paper, we tried to consider the cause of the influence of forest sounds on human hearing from the acoustical aspect. The type of sound source of forest was divided into four seasons of spring, summer, autumn, winter. And the change in the duration of the sound during the four seasons, so that the general characteristics of the sounds of the four seasons are as follows: It can be seen that the change in the ratio of sub-band energy is almost equal to the change in dB in frequency of the equal-light curve. To compare this phenomenon, the criterion for changing the sound duration of each forest is natural The main forms of the luminance curve, such as the change in the duration of the white signal in the sound, are determined by the minimum, maximum audible frequency and the most sensitive frequency band, and the auditory characteristics of the other three inflection points Determines the overall shape of the equal-light curve.