• Title/Summary/Keyword: night time light

Search Result 144, Processing Time 0.023 seconds

Effects of Zinc and Its Chelators on ERG b-Wave Sensitivity During the Light Adaptation in Bullfrog Retina

  • Hwang, Kyung-Hee;Kim, Young-Hwal;Park, Jong-Seok
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.43 no.2
    • /
    • pp.33-42
    • /
    • 2011
  • Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

  • PDF

Effect of Night Interruption with Mist and Shade Cooling Systems on Subsequent Growth and Flowering of Cymbidium 'Red Fire' and 'Yokihi'

  • Kim, Yoon Jin;Kim, Ki Sun
    • Horticultural Science & Technology
    • /
    • v.32 no.6
    • /
    • pp.753-761
    • /
    • 2014
  • Growth and flowering of Cymbidium 'Red Fire' and 'Yokihi' plants were examined in a greenhouse with cooling systems in summer, and with night interruption (NI) lighting in winter as a forcing culture system. The greenhouse was divided into two sections with separate cooling controls during the summer season. One section was cooled by a mist system (mist), while the other section was cooled by a shade screen (shade). During the winter, the greenhouse was redivided into three sections within each cooling system. Plants were grown with NI either at a low light intensity of $3-7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$(LNI) or a high l ight intensity of $120{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$(HNI) u sing h igh-pressure sodium l amps during the 22:00-02:00 HR. The control plants were grown under 9 h short-day condition. NI for 16 weeks and cooling for 9 weeks were employed twice during the 2 years of the experimental period. The air temperature was approximately $2^{\circ}C$ lower in the mist than in the shade and the relative humidity was 80 ${\pm}5%$ in the mist compared to $55{\pm}5%$ in the shade. The daily light integral in the mist section was 48% higher than in the shade section. The time from initial planting to flowering pseudobulb emergence decreased with both LNI and HNI for both cultivars, regardless of the cooling treatments. Under NI conditions, however, between 60% and 1 00% of plants of both cultivars flowered in the mist, whereas no or 20% of 'Red Fire' or 'Yokihi' plants, respectively, flowered in the shade treatment over 2 years. Plants grown under the mist had bigger pseudobulbs than those grown in the shade under both NI treatments. These results show that commercial use of NI in winter and a mist cooling system in summer would decrease crop production time to 2 years and increase profits in Cymbidium forcing culture.

A development of an independent electric power generating portable flashlight by using solar battery (태양전지를 이용한 자가발전 손전등 개발에 관한 연구)

  • Kim, Hong-Il
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.10 no.8
    • /
    • pp.1795-1801
    • /
    • 2009
  • In this study, a portable flashlight which can manually generate the electricity by using sunlight was developed so that it can be used in the extreme environmental condition such as no-electricity condition. Battery is charged by using solar battery during the day, but when sunlight is not avalible during the night or rainy day, a handle is rotated to generate the electricity in order to charge the battery manually. To improve the brightness of the light, light is concentrated by using the optical lens. Low electric consumption circuit is used for the longer operating time by suppress electrical consumption while lamp is discharged. A circuit is designed and used for steady electrical curris dand voltage to insure steady battery charging. Super-discharge circuit and protection circuit are used for the super discharge of battery when it is not used for a long time. Also the constant charge is possible by using houseware adapter. As a result, a portable flashlight is designed to charge with sunlight during day, and with houseware adapter during night. A portable flashlight is also designed to irradiate longer distances by improvement of the brightness of the light using the optical lens. Thus, it forms white natural ray of light making possible for night reading.

Phototaxis of Fish 6. Responce of Sea-bass to the White Lights (어류의 주광성에 관한 연구 6. 백색광에 대한 능성어의 반응)

  • Yang, Yong Rhim
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.23 no.3
    • /
    • pp.27-27
    • /
    • 1987
  • 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 at daytime and night by using Sea-bass, Epinephelus septemfasciatus (Thunberg). An experimental tank (360 L×50 W×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 with white 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 before 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 24.13 lux (15.25~35.93 lux) at daytime and 0.41 lux (0.25~0.63 lux) at night. The variation of the gathering rate of fish in illumination time was great and did not show any definite pattern but fluctuated irregularly. Its different between daytime and night is remarkable.

Phototaxis of Fish 6. Responce of Sea-bass to the White Lights (어류의 주광성에 관한 연구 6. 백색광에 대한 능성어의 반응)

  • 양용림
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.23 no.3
    • /
    • pp.137-143
    • /
    • 1987
  • 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 at daytime and night by using Sea-bass, Epinephelus septemfasciatus (Thunberg). An experimental tank (360 L$\times$50 W$\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 with white 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 before 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 24.13 lux (15.25~35.93 lux) at daytime and 0.41 lux (0.25~0.63 lux) at night. The variation of the gathering rate of fish in illumination time was great and did not show any definite pattern but fluctuated irregularly. Its different between daytime and night is remarkable.

  • PDF

DEVELOPMENT OF REAL-TIME DATA REDUCTION PIPELINE FOR KMTNet (KMTNet 실시간 자료처리 파이프라인 개발)

  • Kim, D.J.;Lee, C.U.;Kim, S.L.;Park, B.G.
    • Publications of The Korean Astronomical Society
    • /
    • v.28 no.1
    • /
    • pp.1-6
    • /
    • 2013
  • Real-time data reduction pipeline for the Korea Microlensing Telescope Network (KMTNet) was developed by Korea Astronomy and Space Science Institute (KASI). The main goal of the data reduction pipeline is to find variable objects and to record their light variation from the large amount of observation data of about 200 GB per night per site. To achieve the goal we adopt three strategic implementations: precision pointing of telescope using the cross correlation correction for target fields, realtime data transferring using kernel-level file handling and high speed network, and segment data processing architecture using the Sun-Grid engine. We tested performance of the pipeline using simulated data which represent the similar circumstance to CTIO (Cerro Tololo Inter-American Observatory), and we have found that it takes about eight hours for whole processing of one-night data. Therefore we conclude that the pipeline works without problem in real-time if the network speed is high enough, e.g., as high as in CTIO.

Development of A Prototype Device to Capture Day/Night Cloud Images based on Whole-Sky Camera Using the Illumination Data (정밀조도정보를 이용한 전천카메라 기반의 주·야간 구름영상촬영용 원형장치 개발)

  • Lee, Jaewon;Park, Inchun;cho, Jungho;Ki, GyunDo;Kim, Young Chul
    • Atmosphere
    • /
    • v.28 no.3
    • /
    • pp.317-324
    • /
    • 2018
  • In this study, we review the ground-based whole-sky camera (WSC), which is developed to continuously capture day and night cloud images using the illumination data from a precision Lightmeter with a high temporal resolution. The WSC is combined with a precision Lightmeter developed in IYA (International Year of Astronomy) for analysis of an artificial light pollution at night and a DSLR camera equipped with a fish-eye lens widely applied in observational astronomy. The WSC is designed to adjust the shutter speed and ISO of the equipped camera according to illumination data in order to stably capture cloud images. And Raspberry Pi is applied to control automatically the related process of taking cloud and sky images every minute under various conditions depending on illumination data from Lightmeter for 24 hours. In addition, it is utilized to post-process and store the cloud images and to upload the data to web page in real time. Finally, we check the technical possibility of the method to observe the cloud distribution (cover, type, height) quantitatively and objectively by the optical system, through analysis of the captured cloud images from the developed device.

A study on the LED lighting for aids to identification of AtoN at night (야간의 항로표지 식별을 지원하는 LED 조명의 연구)

  • Oh, Jin-Seong;Jang, Chul-Woo;Choi, Jo-Cheon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2010.05a
    • /
    • pp.689-691
    • /
    • 2010
  • This study is the visually identification lighting for easy to distinguish using colors LED on AtoN facility in harbor gate, which have realized a controller for certainly express the gate of harbor by red light and green light of both sides a harbor and for synchronization at a time of right and left or sequential the harbor guidance light through synchronizer or timer by GPS. There is expectation effect that is prevent a confusion about distinguish of facility by ship's operator and to beautify a night scene of harbor, which is expressed to identification lighting differ from great many lighting of harbor with variable color lighting the lighthouse body and vertical layer color lighting using LED. Especially the function of AtoN is displayed for harbor safety message by CW lighting, and this system is the power consumption greatly reduce by candle alternated high light LED.

  • PDF

Consideration of LED Saloon light for rolling stock (철도차량 LED 실내등 적용 검토)

  • Jeong, Hyun-Jeong;Kim, Shin-Gug;Ahn, Hong-Kwan;Kim, Jae-Gi
    • Proceedings of the KSR Conference
    • /
    • 2011.05a
    • /
    • pp.1457-1465
    • /
    • 2011
  • The saloon light is the device that can offer convenience and comfort to the driver and passenger when the train is operated at night or in the tunnel. Generally, The fluorescent type saloon for the rolling stock have been used, but the problems that are short life and the generation of heat have been brought about because the saloon lihgts of rolling stock are supposed to operated continuously long time, and high power consumption. So, the development of new type of saloon lights has been requested in order to solve these problems. And recently the various LED type lights have been developed and LED type saloon lights for rolling stock also has been developed. Therefore, we survey the characteristic, function and needed condition of the LED type saloon lights for rolling stock, and analyze the good and bad point, and then research the complement of weak point. We want to find the direction and develop the design of future LED saloon light type.

  • PDF

The LED lamp synchronous light control and charge/discharge system by using GPS (GPS를 이용한 LED 동기점멸등 제어 및 충방전 시스템)

  • Jang, Hye-Young;Son, Young-Dae;Kim, Cherl-Jin
    • Proceedings of the KIEE Conference
    • /
    • 2007.10c
    • /
    • pp.157-159
    • /
    • 2007
  • For a vessel to safely navigate on the ocean, it is required to check the vessel position as frequently as possible. When a vessel navigates oil the ocean or entering/leaving a port, the target area such as islands, points and mountain peak, etc. are used. However, when such target are not available or when vessel navigates in night time, installed artificial navigation aid facilities help successful vessel navigation. Light Wave Aid helps to confirm a position to the navigator directly and quickly. So, the synchronous light to display the accurate signal has wide applications. However, lantern domestic industry is small, and most of the products show non-compatibility. Consequently, this paper presents the synchronous lighting using UTC of GPS, which maintains compatibility with different lanterns. Also, by replacing conventional electric bulb with LED lamp, simple and efficient lighting system is obtained.

  • PDF