• 조명전기설비학회논문지
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• 제26권4호
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• pp.6-13
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• 2012

In this paper, we took an indirect reflectance type that irradiates light from an LED module, which reflects light from a reflector onto the road. This LED pedestrian lighting design produces minimal glare from a relatively simple structure. Using LightTools 7.2, we conducted a study on the varying shape and curvature of the reflector. In order to further investigate this data, we researched the ratio of the DLOR and ULOR, the average illuminance, and the uniformity of the illumination. Based on this research, we selected optimum conditions to realize the actual LED pedestrian lighting using RELUX software. We found the average illuminance value to be 22[1x] and the illuminance uniformity ratio to be 0.23, which met the criteria of the proposed standards set in KS C 7658. In addition, it also satisfied the criteria of the standards set in KS A 3701 by having TI (Threshold Increment) at 7[%].

• 조명전기설비학회논문지
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• 제27권5호
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• pp.9-17
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• 2013

Preferred combinations of illuminance and color temperature of lighting depend on daily living activities. We investigated whether the illumination stimuli of LED lighting can enhance attention and relaxation level by controlling color temperature and illuminance level according to activities. Illuminations and color temperatures of LED flat panels are controlled in accordance with activities such as office work and resting. The attention and relaxation level under the task specific lightings are compared with those under normal lighting condition. Single channel EEG signals from the NeuroSky's Mindset are used to estimate attention and relaxation level of human subjects under different lighting conditions. Experiment results show that high color temperature with high illuminance of LED lightings (6600K, 800lx) shows improved attention level compared with conventional lighting conditions (4000K, 500lx).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.453-454
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• 2008

본 논문은 가로등 LED조명 설계를 위해 LED(Light Emiting Diode)소자 특성 분석 및 시뮬레이션을 통한 광 특성을 개선하고자 하였다. 시뮬레이션은 Geometry 와 Optic 특성을 고려하였으며, 광속, 스펙트럼, 지향각, 조도값 분석을 통해 제품과 시뮬레이션 특성을 비교하였다. 광 특성 개선 설계변수로는 $30^{\circ}C{\sim}50^{\circ}$ 사이의 2차 렌즈를 각도별로 설계하여 35 도 렌즈 각도일 때 최대 조도특성을 확인했으며, LED 모듈간 간격 배치는 3Cm 일 때 가장 높은 조도특성이 나타났다. 9개의 LED모둘 각도를 정면 Angle($\theta1$)과 측면 Angle($\theta2$)으로 구분하여 각도에 따라 배치 시켜본 결과, 정면 Angle($\theta1$)은 0도일 때, 측면 Angle($\theta2$)은 10도 일 때 가장 높은 조도 특성이 나타났다.

• 한국태양에너지학회 논문집
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• 제31권2호
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• pp.31-36
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• 2011

LED is expected as an environmentally friendly next generation light source with its good reliability and long lifetime. The light sources for illumination have a variety of applications in the indoor and outdoor, and the variation of optical power and color rendering of the light source limits their applications. Therefore, it is necessary to research the LED lamp and its luminaire to minimize the variation of dynamic characteristics and to improve the color rendering due to that illuminating environment. Daylight is very good light source to human and can be used as primary or a secondary light source with benefits of energy, productivity and health.This paper presents the design method of LED lighting system to improve poor property in terms of CR(color redering) characteristic to use daylight effectively.

• 전기학회논문지
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• 제62권5호
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• pp.696-704
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• 2013

In this paper, we introduce the LED emotional lighting system realized with the aid of both intelligent algorithm and RGB LED combined with White LED. Generally, the illumination is known as a design factor to form the living place that affects human's emotion and action in the light- space as well as the purpose to light up the specific space. The LED emotional lighting system that can express emotional atmosphere as well as control the quantity of light is designed by using both RGB LED to form the emotional mood and W LED to get sufficient amount of light. RBFNNs is used as the intelligent algorithm and the network model designed with the aid of LED control parameters (viz. color coordinates (x and y) related to color temperature, and lux as inputs, RGBW current as output) plays an important role to build up the LED emotional lighting system for obtaining appropriate color space. Unlike conventional RBFNNs, Fuzzy C-Means(FCM) clustering method is used to obtain the fitness values of the receptive function, and the connection weights of the consequence part of networks are expressed by polynomial functions. Also, the parameters of RBFNN model are optimized by using PSO(Particle Swarm Optimization). The proposed LED emotional lighting can save the energy by using the LED light source and improve the ability to work as well as to learn by making an adequate mood under diverse surrounding conditions.

• 한국광학회지
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• 제31권6호
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• pp.334-343
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• 2020

본 논문에서는 LED의 hot spot으로 인해 발생하는 눈부심을 감소시키기 위하여 간접광을 형성하는 조명 광학계 설계에 관한 연구를 진행하였다. LED를 실내 조명의 광원으로 사용하는 경우, 높은 휘도와 hot spot으로 인한 불균일한 휘도 분포로 인해 사용자에게 눈부심을 발생시키는 문제점이 있다. 특히, LED 스탠드의 경우 사용자의 눈에 가깝게 위치되어 있으며, 장시간 사용되기 때문에 눈부심 감소를 위한 연구가 필수적이다. 따라서 본 논문에서는 눈부심을 감소시키기 위한 LED 스탠드 광학계 구조 연구 및 설계를 진행하였다. 이후, 기존 LED 스탠드 제품과의 휘도 비교 및 분석을 통해 본 논문에서 제안한 반사형 LED 스탠드가 눈부심 면에서 더 우수한 성능을 가지는 것을 확인하였다.

• International Journal of Advanced Culture Technology
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• 제4권4호
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• pp.6-12
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• 2016

Due to the development of technology, the modern people became to require not only more convenient life but also more comfortable and emotional environment, and individually suitable living environment is applied to residents in a residential space. Recently, while the LED lighting was variously attempted in every sector in society, it is needed to express differentiated lighting according to the resident's individual lifestyle in a residential space. In this paper, we analyze the role of LED lighting suitable for the digitalized lifestyle of the modern people through the relevant literature survey and case studies. The following results are obtained in summary of the rapidly changed recent trends of LED lighting. First, LED light replace existing light sources due to the advanced new technology in LED industry, and take the spotlight as a new lighting solution with the development of variable color LED bulb and the control technology by the wired and wireless communications. Second, LED lighting can be structurally applicable to every lighting device because of its compact and lightweight units, can produce abundant light environment by expression of variable colors and moods with the easy coloring and dimming control, can be reborn as emotional lighting design. Third, as recently practices are constantly appeared that integrate LED lights in the interior elements, such as object and furniture, and combine advanced LED lighting technology to new materials, the portion of illumination on the indoor environment is further increased after integrating the LED lighting and interior elements make boundaries of lighting and product architecture become blurred. LED lighting is confirmed that is being changed from the external functionality including material, shape, color, and etc. into the contextual emotion design including the lights expression, variable color, brightness control, making image, and etc. as the light source in current smart lighting era.

• 수산해양기술연구
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• 제46권4호
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• pp.503-508
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• 2010

Common LED (Light Emitting Diode) lamp has many advantages to compare with fluorescent lamp, long life and no pollution matter like the mercury. The LED lamp is a good light source especially for shipboard lighting because of its compact structure which prevents explosion and shock. Also, low maintenance cost is expected due to its longer life time in comparison with conventional lamps. The LED lamp, however, need some estimates that change of voltage and frequency, vibration, moisture on board to definite accommodation of the LED lamp to shipboard. The purpose of this study is to compare physical properties of a fluorescent lamp with one of the common LED lamp so as to analyze accommodation of common LED lamp on board. This study was carried out in two stages. First, temperature, humidity of illumination, voltage, electric current, frequency and electric power were measured by using experimental equipments. Second, a comparative analysis of consumption electric power, annual oil charge, annual CO2 emission and lamp life time, etc of the fluorescent lamp and common LED one was made. As a result of the study, the consumption electric power of fluorescent lamp was 50% higher than one of the common LED lamp. As a result of measuring life time, it was found that life time of common LED lamp was more about 3.5 fold than one of the fluorescent lamp. Considering these results, it's thought that common LED lamp is verified that energy saving is possible and using is possible as substitute for fluorescent lamp on board.

• 전기학회논문지P
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• 제63권3호
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• pp.178-182
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• 2014

This paper investigates the lighting environment of railway system which are mainly used in KTX, Saemaul and Mugunghwa. When lighting used in KTX such as fluorescent lamp and incandescence is being replaced with LED lamp, illumination load of each railroad vehicle has been compared. The comparison result shows that the reduction of power consumption is 43.34% before and after the change. Also it has been performed the economic evaluation.

• Journal of Advanced Marine Engineering and Technology
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• 제38권2호
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• pp.169-174
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• 2014

This paper proposes a novel beehive-shaped reflector for application to light-emitting diode (LED) transceivers for illumination and bi-directional visible light communication (VLC). By using a diffuse propagation model extended to line-of-sight and direct signals, the distribution of illuminance and the path loss of the transceiver are investigated to evaluate the performance of the beehive-shaped reflector. To verify bi-directional communication, a VLC-based image capture system, comprising a complementary metal-oxide semiconductor (CMOS) image sensor and video processor unit, is demonstrated. Real-time images captured by the CMOS camera are successfully transmitted to the monitoring system via a free-space channel at a rate of 115.2 kbps.