• Title/Summary/Keyword: lighting condition

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A Simulation Study on the Improvement of Lighting Condition on Sidewalks Considering the Type and Growth of Roadside Trees (가로수의 유형 및 성장을 고려한 보행로 조명환경 개선에 관한 시뮬레이션 연구)

  • Lee, Jong-Sung;Lee, Seok-Jun
    • Journal of the Korea Safety Management & Science
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    • v.15 no.3
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    • pp.93-103
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    • 2013
  • In recently, a growing concern for the health of urban residents increased interests in a variety of outdoor activities simply be done in terms of cost and time. They are specially interested in low-impact and safe exercises around residential or working area. Walking is the one of easily doing exercise in daytime or nighttime near residential area. The sidewalks of boulevard near the residential area is the best place for exercise because of easy access and the green space with roadside trees. However, if the nighttime is not guaranteed the proper lighting condition, the possibility of exposure to crime and the threat to pedestrian safety can be increased. Because roadside trees are one of the potential obstacle for lighting condition, supplementary lightings are important to mitigate interruption for safety. To meet such a need, the purpose of this study is to propose a simulation approach which improves lighting condition on sidewalks of boulevard with variety of roadside trees. To do so, the simulation approach is applied for analyzing the interrupted condition by classified five standard types of roadside trees considering the growth of them and finding optimal layout of supplementary luminaires by lighting types. The results of this approach shows that it is useful for assessing the safety of pedestrian in nighttime.

Evaluation of the Lighting Characteristics in High Power White LED Module with Cooling Condition (방열 조건에 따른 5W급 고출력 백색 LED 모듈의 광 특성 평가)

  • Yun, Janghee;Ryeom, Jeongduk
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.12
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    • pp.1-8
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    • 2012
  • The performance and lighting characteristics of the LED depend on cooling condition because the power LED generates lots of heat. In this paper, the effect of the generated heat from power LED module on lighting characteristics and performance is measured and evaluated. For experiments, the transient temperature of a power LED module with cooling condition is measured. In addition, the temperature and lighting characteristics of the LED module are measured during the steady state. As a result, the cooling condition is less effective on the lighting characteristics of the LED module at rated current but the cooling condition extremely affects those of the LED module over the rated current. Because high temperature of the power LED module causes the low phosphor conversion, luminance efficiency becomes low and color temperature becomes high. When power LED module are driven over the rated condition, higher temperature is directly related to lighting characteristics and performance of the LED module rather than higher current.

A Study on the Actual Condition of Illumination Environment in Public Libraries in Daegu

  • Seo, Ji-Eun;Kim, Hyun-Ji;Kim, Sung-Hwa;An, Ok-Hee
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.3
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    • pp.1-9
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    • 2009
  • This study investigated the actual condition focusing on the lighting environment which is a major element in aspect of indoor environment of a public library and assessed user satisfaction. Research results are as follows: Firstly, numbers of lighting fixtures per dimension of a reading room in a public library were inconsistent due to the lack of definite regulations, which was found to have negative effect on night time illuminance. Secondly, it was assessed that illuminance between the day time influenced by natural lighting and in the nighttime without natural lighting has more than 10-fold difference. Therefore, such a condition is judged to be inappropriate for lighting environment of a reading room where users spend a long time studying and thus, it is considered that an appropriate measures should be taken. Thirdly, as the survey result on users' satisfaction with lighting environment was revealed to be lesser than 3 points, lighting plan in consideration of its users should be progressed.

Suggested Accelerated Life Test Method of SMPS for Outdoor Lighting LED (실외조명 LED용 SMPS의 가속수명시험법 제안)

  • Lim, Seong-Yong;Hyong, Jae-Phill;Lim, Hong-Woo;Oh, Geun-Tae
    • Journal of Applied Reliability
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    • v.18 no.1
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    • pp.8-19
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    • 2018
  • Purpose: This study has developed the accelerated lifetime test method for smps for outdoor lighting LED through two factors of temperature and humidity. Methods: Acceleration condition was confirmed for each stress and model, and acceleration life test model was estimated according to acceleration condition. Results: As a result of confirming the accelerated life test model, in the case of humidity, acceleration was established only in the foreign products. Therefore, it is confirmed that the acceleration condition is insufficient. However, the estimated parameters for temperature are relatively constant. It is therefore suitable for power supply acceleration tests for outdoor lighting LEDs. Conclusion: The SMPS acceleration test for outdoor lighting LED can improve the availability of the product by developing an accelerated life test method that guarantees the reliability of the product.

Effect of Different Lighting Sources on Behavior and Growth of Weanling Pigs

  • Glatz, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.2
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    • pp.280-287
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    • 2001
  • These studies aimed to determine how lighting might be used to improve feed intake and reduce aggressive behavior in newly weaned pigs. To examine whether this objective could be achieved an experiment was conducted to compare performance, behavior and body condition of weaners over 17-45 days, provided similar lighting quality (i.e. color temperature, color rendering index and lighting distribution) after weaning that piglets experienced prior to weaning. Triphosphor (TP) lighting to simulate daylight was provided during the day while at night, Pascal red (PR) lighting was provided to simulate the night-light piglets previously had received from infrared heating lamps. This treatment was compared to weaners provided conventional cool-white fluorescent light during the day only. Weaners on treatment lighting from 17-45 days of age showed no improvement in body weight or feed conversion at 24, 31, 38 and 45 days compared to the controls. There was, however, a significant improvement (p<0.05) in feed intake in the first week of weaning for weaners provided TP/PR lighting. Over the first 3 days of weaning, pigs on TP/PR lighting showed an increase (p<0.05) in the incidence of ear chewing but reduced (p<0.05) levels of nosing the abdomen of other pigs and reduced (p<0.05) occurrences of being stood on by other pigs. Females exhibited more (p<0.05) mounting and nosing behaviors and rubbing the heads of other pigs than males. On the other hand, males engaged in more (p<0.05) fighting, nipping, ear chewing and standing on other pigs compared to females. Pigs provided PR lighting on the first night of weaning engaged in higher (p<0.05) incidences of nosing and tail sucking behaviors, more (p<0.05) head thrusting, fighting and ear chewing compared to control pigs. The body condition of weaners provided the TP/PR lighting treatment was significantly poorer (p<0.05) compared to weaners on control lighting. In conclusion there was no improvement in production performance of weaners provided new technology lighting apart from the improvement in feed intake in the first week weaners were exposed to the TP/PR lighting.

Prediction of Contrast and Lighting Energy Saivings in a Small Office Space according to Daylight Conditions (소규모 사무실공간에서 주광조건에 따른 대비효과 및 조명에너지 절약예측)

  • Kim, Soo-Young
    • 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.

The Study of Costomer's Mood Preferences Influenced From The Lighting Environment-In Coffee Shop- (조명환경이 제공하는 MOOD에 대한 고객의 선호도 조사연구-Coffee Shop을 중심으로-)

  • 강무진
    • Korean Institute of Interior Design Journal
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    • no.4
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    • pp.16-21
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    • 1995
  • Although it has been suggested that lighting influences our moods, little is known about dimensionality of mood patterns. The knowledge of consumer's mood pattern in lighting condition may provide interior designers with a valuable information for the lighting design. This article investigates the underlying structure of moods occuring in lighting conditions. Meanwhile, this examines custom-ers' desired mood type of lighting, and explores the influ-ence of individual characteristics on selecting the preffered lighting moods. The result uncovers five discriminable patterns of mood-dynamic, intimate, delightful, elegant, and serene feeling results from well organized lighting system. Among the five moods, serene atmosphere appears to be the most preffered mood from respondants. It is also found that the perceived preference of lighting atmo-sphere varies across personal characteristics of the cus-tomers, socio-economic differences and the visiting pur-poses to the coffeeshop. These findings present interest-ing and potentially valuable implications for interior de-signers that proper planning of lights which inducemoods can achieve dramatic effects and aid in the cre-ation of the desired atmosphere.

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A Study on the Condition of LED Lights Flicker (국내 LED 조명등에서 플리커 현상에 관한 연구)

  • Heo, Min;Ko, Jae-jun;Kim, Chung-hyeok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.11
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    • pp.729-735
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    • 2016
  • It is highly important issue to use an energy efficiently for sustainable prosperity of mankind. From this point of view, using LED lighting can be a good alternative because it has a lot of advantages such as high efficiency, long life time and eco-friendly manufacturing process. That is the reason why using LED lighting has been encouraged worldwide. However, in situations that LED lighting is replacing traditional lighting quickly, the problem of the flicker of LED lighting has emerged as an important issue. Therefore, in foreign countries like US or Japan in order to ensure the reliability of LED lighting, study for flickering effects of the human body and test methods are have been actively conducted. But related research in domestic situation is an insufficient condition. In this study, a flicker characteristic was measured conventional lamps such as incandescent lamps or fluorescent lamp and 81 items of LED lightings which are distributed in domestic markets.

A Study on the Plant Cultivation by comparing Ultra Constant Discharge (UCD) Lamp lighting and Hi-Pressure Sodium Lamp lighting (초정압방전램프(UCD)와 나트륨램프를 적용한 식물재배에 관한 연구)

  • JEONG, P.G.;KIM, Y.C.;YANG, H.S.
    • Journal of the Korean Society of Mechanical Technology
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    • v.13 no.1
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    • pp.31-40
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    • 2011
  • This study was conducted to research how UCD(Ultra Constant Discharge) lamp lighting affects plant cultivation. To get the results within a short time, lettuce seedling was selected as a plant and nutrient hydroponic beds were used in a dark room for 100% artificial lighting. Two beds were installed for same distance lighting condition with UCD lamp and Hi-pressure Sodium lamp each and another two beds were installed for same light intensity condition with each type of lamp. After 15 days of cultivation, for both conditions, the yields under UCD lamp were weighed more than that under Hi-pressure Sodium lamp. The result can be analyzed that the spectrum of UCD lamp having near sunlight characteristic is much superior to that of Hi-pressure Sodium lamp having a line spectrum characteristic on yellow and red wavelengths for plant cultivation.

Face Identification Method Using Face Shape Independent of Lighting Conditions

  • Takimoto, H.;Mitsukura, Y.;Akamatsu, N.
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2213-2216
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    • 2003
  • In this paper, we propose the face identification method which is robust for lighting based on the feature points method. First of all, the proposed method extracts an edge of facial feature. Then, by the hough transform, it determines ellipse parameters of each facial feature from the extracted edge. Finally, proposed method performs the face identification by using parameters. Even if face image is taken under various lighting condition, it is easy to extract the facial feature edge. Moreover, it is possible to extract a subject even if the object has not appeared enough because this method extracts approximately the parameters by the hough transformation. Therefore, proposed method is robust for the lighting condition compared with conventional method. In order to show the effectiveness of the proposed method, computer simulations are done by using the real images.

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