• Photonics industry news
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• s.36
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• pp.58-65
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• 2006

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.384-391
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• 1997

In the cultivation of Bupleurum falcatum, one of the problems to surmount is long-term germination period and unstable germination. This experiment was done to examine the effect of $GA_3$ concentration [0(water), 0.01, 0.lmM], chilling, their treatment period [2, 4, 8 days ($GA_3$) : 0, 2, 4 weeks (chilling)] and light quality (red, white, dark) given during the period as pretreatment before sowing on the seed germination of its two cultivars (cv. Jaerae, cv. Jangsu). Light treatment was given during all the periods of $GA_3$ treatment or for 0, 2, 4 days at the end of the chilling treatment. There was no difference in the mean germination rate between the levels of all the treatments except the $GA_3$ concentration meaning that water imbibition and $GA_3$ treatment had the same effect. As light quality treatment during the water imbibition was forced, the mean germination rate of Jaerae, 2 to 4 days imbibition period or red light was more increased or accelerated compared to the other levels of the same treatment, respectively. The rate of Jaerae not affected by the light quality was the greatest in the 2 days water imbibition while the rate of Jangsu was the greatest when water-imbibed for 4 days or treated by red light. No chilling before sowing showed the highest rate due to the light quality and white light forced after sowing had greater rate than the dark treatment. Although there was no difference between the rates of light quality treatment levels in the condition of no chilling before sowing and white light treatment after sowing, the rate of Jangsu was enhanced or accelerated only under illumination during 2 days water imbibition before sowing.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.37-43
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• 1989

The purpose of this study is to find the light intensity which induced maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by suing Rudder fish, Girella punctata(Gray). An experimental tank(360L*50W*55H cm) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Eight artificial light sources were prepared by combination of three light bulbs(10W, 60W, 100W) and eight filters. During the experiment water depth was maintained 50cm level in the tank. The tank was marked into six longitudinal sections each being 60cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 60 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 2.98 lux(1.90-4.40 lux) at daytime and 298.56 lux(188.44-444.96 lux) at night. The variation of the gathering rate of fish in illumination time was great and irregularly fluctuated, but did not show any definite pattern. It was somewhat difference between daytime and night.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.4
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• pp.144-149
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• 1988

The purpose of this study is to find the light intensity which induced maximum gathering rate and to observe the variation of the gathering rate both in daytime and tat night by using Striped puffer, Fugu xanthopterus (Temminck et Schlegel). An experimental tank(360L$\times$50W$\times$55H cm) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Eight artificial light sources were prepared by combination of three light bulbs (10W, 60W, 100W) and eight filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 60 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 298.56 lux (188.44-444.96 lux) at daytime and 298.56 lux (188.44-444.96 lux) at night. The variation of the gathering rate of fish in illumination time was increasing trend fluctuately and did not show any distinctive difference between day and night.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.49-56
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• 2008

Typical rose flowers, 'Red Corvette (red)', 'Nobless (pink)', 'Golden Metal (yellow)', and 'Rose Yumi (white)', were used as experimental materials to examine flower color changes as affected by pressing method and light treatment for four weeks and eight weeks by 2,000 lux fluorescent light at a 16 hours daylength. Pressing materials in silicagel mat resulted in the least change after pressing and light treatment for all kinds. On the contrary, an electric pressing device caused color to change to brown. Flower colors deteriorated the most by an electric pressing device made in Korea for pink rose; an electric pressing device made in Japan for white rose; and paper sheet made in Korea for red rose. The sequence of degree in severity of color change after pressing was pink, yellow, and white roses. Light treatment brought about the most extreme color change in yellow 'Nobless' rose, while other three cultivars were rather stable in change of color.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.558-562
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• 1986

The purpose of this study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by using marbled sole, Limanda yokohamae (Gunther). An experimental tank ($360L{\times}50W{\times}55H\;cm$) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 40 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 1.9 lux ($1.2{\sim}2.9\;lux$) in the daytime and 0.7 lux ($0.5{\sim}1.1\;lux$) at night. The variation of the gathering rate of fish in illumination time was small and comparatively fluctuated with stability.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.12
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• pp.23-30
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• 2009

LEDs are increasingly used for many applications including automotive, aviation, display, transportation and special lighting applications. Generally, the RGB multichip LED luminaire applied to signboard, emotional lighting system and display device and the white LED luminaire applied to general lighting system. white LED spectra for general lighting should be designed for high luminous efficacy as well as good color rendering. This paper describes characteristics of LED luminaire white LED and RGB multichip LED. Two type of LED luminaire prototype used experiment physical, electrical and optic test and performance analyzed. RGB multi-chip and phosphor-type white LED luminaire were analyzed by experiment on their color characteristics and luminous efficacy of radiation, distribution curve, and electrical characteristics. Research work is in progress to develop an improved performance for optic and electrical works well for two type of LED luminaires.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.5
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• pp.212-217
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• 2021

The applicability of the white LED from the blue LED of the coating film as a binder for surface and curved coatings were confirmed. The particle size of YAG is D₅₀: 9~10 ㎛, and the crystal structure is garnet (Y₃Al₅O₁₂), cubic. The coating film had no cracks, at the same time, the silica sol was uniformly coated with YAG phosphor, and the YAG content and thickness in the coating film showed a tendency to increase up to 40 ㎛ in proportion to the increase in the amount added. Furthermore, as the YAG content increased, the PL emission intensity increased and the color coordinate shift toward the end of the chromatic locus curve was confirmed.

• Korean Journal of Plant Resources
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• v.20 no.5
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• pp.466-470
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• 2007

Nowadays burcucumber(Sicyos angulatus L.) has been widely used as a rootstock of Cucurbitaceae. The study was done to examine the effects of shading with different colored fabrics(white, red and aluminum-coated) on growth and cotyledon chlorophyll content of its seedling. Shading with the white colored fabric lengthened seedling height and hypocotyl length, but shading with the red colored fabric enlarged true leaf area. Total dry weight of each seedling was decreased in the order of no shading, white, red and aluminum, in which resulted from reductions of cotyledon dry weight in white colored fabric, cotyledon and true leaf dry weight in red colored fabric, and dry weight of cotyledon, true leaf and root in aluminum colored fabric. Cotyledon chlorophyll content was reduced by shading treatments although the 3 shading treatments showed nearly same content.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.198-198
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• 2003

LED(Light Emitting Diode)는 전기 신호를 빛으로 신호를 보내고 받는데 사용되는 반도체의 일종으로 가정용 가전제품, 리모컨, 전광판, 각종 자동화 기기등에 사용된다. 3색광 백색 LED는 soft-UV 또는 blue 빛을 내는 device 와 RGB 형광체로 이루어져 있다. 현재 연구중인 3색광 백색 LED는 InGaN 또는 GaN 이 RGB 형광체를 여기 시키는것이 대부분이다. 이러한 경우에 유기물과 무기물 형과체가 백색광을 구현하기 위해 사용된다. 유기물의 경우에는 lift-time 이 짧고, 무기물의 경우에는 유해원소인 S, Cd등이 포함되기 때문에 환경오염이 야기된다. 이러한 단점을 보완하기 위해 진화 최적방법을 이용하여 alkali earth borosilicate ((Eu,Mg,Ca,Sr,Ba)$_{x}$ $B_{y}$ S $i_{z}$ $O_{d}$ ) 계열에 $^{Eu3+}$을 도핑하여 고효율 형광체를 합성하였다.