• Korean Journal of Poultry Science
• /
• v.45 no.4
• /
• pp.245-252
• /
• 2018

This study investigated the effect of LED light wavelength (color) on reproductive hormones and egg production of brown laying hens raised on floor. Red, blue, green and white colors of LED light were four treatments with four pens per treatment. One hundred forty four Hy-line brown laying hens (47 wks old) were allocated in a floor pen for six weeks trial. Egg production, egg quality, yolk cholesterol and hormones ($17{\beta}$-estradiol, progesterone) concentrations in plasma and oviduct were analyzed. Egg production of red group was higher (P<0.01) than that of green group. Haugh unit of eggs from red group was higher (P<0.01) than that of blue and green groups. Egg weight of green group was heavier (P<0.05) than that of red group. Shell of blue group was stronger (P<0.05) than that of red and white groups. Shell color of white group was browner (P<0.01) than that of blue and green groups. Yolk cholesterol of red group was higher (P<0.01) than that of others. Plasma $17{\beta}$-estradiol of red group was higher (P<0.05) than that of others at $3^{rd}$ week, but that of white group was highest (P<0.05) at $6^{th}$ week. Oviduct progesterone of green group was higher (P<0.01) than that of others. The result showed that the LED colors affect the reproductive hormone concentrations, egg production, egg weight and egg quality. This study suggested that red LED would be the most appropriate color for floor raising brown laying hens to sustain the egg production when it begins to decline with aging.

• Korean Journal of Optics and Photonics
• /
• v.20 no.2
• /
• pp.110-117
• /
• 2009

This work introduces the uncertainty evaluation formulation on color measurement of light sources and display devices, such as CIE 1931 (x, y) chromaticity, CIE 1960 (u, v) chromaticity, correlated color temperature, and distribution temperature. All the mentioned quantities are reduced from spectral data in the visible range, for which uncertainties are strongly correlated between different wavelengths. Using matrix algebra we have formulated the uncertainty propagation from the SI- traceable spectral irradiance standard to the individual color related measurement quantities taking the correlation between wavelengths into account. As a result, we have demonstrated uncertainty evaluation examples of 3 types of light sources: CIE illuminant A, LED white light, and LCD white light. This method can be applied to any other quantities based on spectral measurement such as solar irradiance, material color measurement, etc.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.26 no.1
• /
• pp.80-82
• /
• 2013

White light emitting diode (LED) determined the most appropriate color temperature in reading lighting evaluated fatigue degree of eye according to color temperature. The eye fatigue degrees are determined by brightness and color temperature. Therefore, we measured the results of eyes test according to the change of color temperature and brightness. Experiments except for astigmatic corrected visual acuity of 0.8 more and age 20 to 25 years old, male and female college students was conducted in 100 patients. And constant illumination conditions, visual acuity was measured by varying the color temperature. The optometry at 10 minutes in the darkroom adapted eye. And then the temperature of $25{\pm}3$ degrees, the humidity was carried out at $50{\pm}5%$. As a result of typical color temperature of white light (5,600 K) has identification of the readability.

• Journal of Broadcast Engineering
• /
• v.15 no.1
• /
• pp.76-88
• /
• 2010

Recently, LED background image devices are used for the production of broadcasting programs. But the effective advantages of LED background image devices are not realized for good HD video quality because the correlations between lighting sources and LED background image devices are not analyzed yet. In this paper, we analyze the color change and light intensity that lighting sources and the light intensity ratio of LED background images influence on a subject, making use of equipments used in real broadcasting, and examine the correlations between HD video quality and the light intensity ratio of LED background images. As a result in this experiment, the video is most expressed having an 20[IRE] effect on a subject when the light intensity of LED background image is 6%. When the LED background image is light, the light and darkness of video is distorted and when the LED background image is dark, the colors of image are distorted.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.63 no.9
• /
• pp.1312-1316
• /
• 2014

The color and the installation position of the LED lamp for night voyage of the ship are changed by the purpose of it. The power dissipation occurs because a navigation light is on and off or continuously on. In addition, in case that the light is produced by operating generator in the ship, it's very inefficient except that it's on a voyage. Therefore in this dissertation, we construct auxiliary power system for the LED lamp of the ship, producing and developing a module, a panel, and a charging system using Dye-sensitize Solar Cell.

• Journal of Information Display
• /
• v.13 no.1
• /
• pp.37-42
• /
• 2012

An empirical functional form was suggested for the analysis of the emission spectrum of high-power light-emitting diode (LED) consisting of a sharp blue peak from the LED chips and a broad yellow peak from the phosphor layer. The peak positions, half widths, shape parameters, and amplitudes of these two peaks were reliably obtained as a function of the temperature, and the results were discussed qualitatively in relation with the junction temperature. The adoption of an inert liquid was found to have significantly reduced the LED temperature and the color shift of the emitted light. The phenomenological approach used in this study may be helpful in the simulation of the LED spectrum under various thermal conditions, and may thus be helpful in the improvement of the device performance.

• Proceedings of the KIEE Conference
• /
• 2006.04a
• /
• pp.348-350
• /
• 2006

Currently the indication method of the traffic signal light which is established in our country displays each "red, yellow, green" using the brightness LED signal light. In this paper, one LED circular arrangement replaces the Current indication method of the traffic signal light using two color LED. Also the blinking signal function of present time uses the MCU of AVR series and it is embodied with magnification and abridgment of the circular arrangement for recognizing easily far away. The signal light indication method which is proposed will be able to substitute the signal light of 3 colors with 1 signal light with economic profit presented the reform measure of energy efficiency improvement together.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2008.05a
• /
• pp.168-171
• /
• 2008

항로표지용 LED 등명기는 완전방수형 구조이며, 발광형태도 섬광 특성을 가진다. LED 등명기의 색도 및 광도 측정에 있어 섬광형태로 측정하는 것은 그 한계가 있으며, 이에 부동광(연속광)으로 측정이 이루어진다. 이때 중요하게 취급되어져야 할 것이 예열시간이며, 적정한 예열시간 선정에 따라 Field와의 오차를 줄일 수 있다. 본 논문에서는 해상용 LED 등명기의 색도 측정 시에 고려해야 하는 예열 시간을 실험을 통하여 산정해 보았다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.05a
• /
• pp.204-207
• /
• 2009

LED 광원의 광학적 성능이 발전함에 따라 광원으로서의 광학효율이 기존 광원을 대체할 정도의 수준을 만족하고 있으며, 이에 의해 실내 조명광원으로서 활용도가 점차 증가하고 있다. 하지만, LED 광원의 경우 기존 광원과는 판이한 분광분포를 가지고 있으며, 소형 광원의 군집체로서 조명기구를 형성하기 때문에 이를 이용하는 사용자들에게 이전의 조명기구와는 크게 다른 느낌, 분위기 등을 가질 수가 있다. 본 연구에서는 기존광원과 LED 광원과의 차이점을 분석하고 이러한 차이점 즉, 분광분포 및 조명기구의 구성 형태 등에 따른 피험자들이 느끼는 색 편차, 조명 분위기의 변화 등을 평가 시험할 수 있는 실험실의 구성안을 제시하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.05a
• /
• pp.466-471
• /
• 2009

Generally LED lamp has many advantages to compare with a general lamp, long life and no pollution matter like the mercury. Also it is excellence for color rendering and need to small consumption electric rower. However LED lamp has some disadvantages to compare to general fluorescent lamp and That is small light flux about 50% and narrow light distribution than fluorescent lamp. Therefore, to apply LED lamp in an office building, after analyze a illuminance distribution with an environment analysis and cooling, heating and light energy. The purpose of this study is to analyze light environment. light, cooling and heating energy simulation in Office building.