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Author Kim, K.-M.; Kim, Y.-W.; Oh, S.-T.; Lim, J.-H. url  doi
openurl 
  Title (up) Development of a natural light reproduction system for maintaining the circadian rhythm Type Journal Article
  Year 2019 Publication Indoor and Built Environment Abbreviated Journal Indoor and Built Environment  
  Volume in press Issue Pages 1420326X19855421  
  Keywords Lighting; Human Health; Circadian Rhythm; indoor light  
  Abstract Circadian rhythm is linked to sleep, arousal and human health overall, affecting body temperature and heart rate. A 24-h natural-light cycle provides optimum lighting environment for humans. However, as people increasingly stay indoors with artificial lighting, lacking periodic characteristics, imbalance in the circadian rhythm ensues. Previous lighting-related studies to resolve such problem partially provided the colour temperatures of natural light but failed to reproduce the 24-h periodic characteristics of it. This study proposes a natural light-reproducing system that provides the daylight cycle characteristics of natural light in order to maintain the circadian rhythm. Natural light was measured through an optical measurement equipment, while the characteristics (colour temperature and short-wavelength ratio) of natural light by season and time were analysed. Subsequently, the control indicator of seasonal and hourly lighting was extracted and applied to the light-emitting diode lighting to provide lighting service, executing a daylight cycle that reflects the characteristics of natural light. After the sunset, especially, the circadian rhythm was maintained by minimizing the short-wavelength ratio of the lighting while maintaining indoor illumination.  
  Address Department of Computer Science & Engineering, Kongju National University, Cheonan-si, South Korea  
  Corporate Author Thesis  
  Publisher Sage Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1420-326X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2591  
Permanent link to this record
 

 
Author Huang, B.J.; Wu, M.S.; Hsu, P.C.; Chen, J.W.; Chen, K.Y. url  doi
openurl 
  Title (up) Development of high-performance solar LED lighting system Type Journal Article
  Year 2010 Publication Energy Conversion and Management Abbreviated Journal Energy Conversion and Management  
  Volume 51 Issue 8 Pages 1669-1675  
  Keywords Stand-alone solar system; Off-grid solar system; Solar-powered lighting; LED lighting; Solar LED lighting; LED; outdoor lighting  
  Abstract The present study developed a high-performance charge/discharge controller for stand-alone solar LED lighting system by incorporating an nMPPO system design, a PWM battery charge control, and a PWM battery discharge control to directly drive the LED. The MPPT controller can then be removed from the stand-alone solar system and the charged capacity of the battery increases 9.7%. For LED driven by PWM current directly from battery, a reliability test for the light decay of LED lamps was performed continuously for 13,200 h. It has shown that the light decay of PWM-driven LED is the same as that of constant-current driven LED. The switching energy loss of the MOSFET in the PWM battery discharge control is less than 1%. Three solar-powered LED lighting systems (18 W, 100 W and 150 W LED) were designed and built. The long-term outdoor field test results have shown that the system performance is satisfactory with the control system developed in the present study. The loss of load probability for the 18 W solar LED system is 14.1% in winter and zero in summer. For the 100 W solar LED system, the loss of load probability is 3.6% in spring.  
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  ISSN 0196-8904 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 330  
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Author Agbo David, O., Madukwe Chinaza, A., & Anyalewechi Chika, J. url  doi
openurl 
  Title (up) Development of Solar Power Intelligent Street Lights System Type Journal Article
  Year 2019 Publication International Journal of Scientific and Research Publications Abbreviated Journal  
  Volume 9 Issue 6 Pages  
  Keywords Lighting; Energy  
  Abstract The lack of natural light during night time in the urban environment has always been a problem. From people not being able to see where they are going, to the greater chance of being attacked or mugged at night which as we all know is a problem that has been in existence since humans started living together. The main advantage of this system exists in the reduction of costs related to energy consumption by the street light by integrating a vehicle/human detection algorithm into the system. The introduction of this vehicle/human detection algorithm further reduces the power consumption costs. In this project, solar PV is used to supply the energy to charge the battery. The battery later powers the operation of the whole system. The 12- 17V of the solar is buck to a steady 12V for battery charging. A light sensor is connected to the microcontroller that sense the light during day time, when the presence of day light is sensed the microcontroller turns ON the mosfet of the buck converter. If the voltage of the solar PV is greater than 12V, it charges the battery and switches off the load transistor. But at dawn, when the solar PV voltage is less than 12V the microcontroller turn OFF the buck converter mosfet and switch ON the load transistor. When no vehicle or human is detected for 10mins the microcontroller dims the LED lamp. If vehicle or human is detected the microcontroller brighten the LED lamp and inform the next microcontroller to brighten its LED lamp. If the next street light did not detect a vehicle or human after 10 mins it dims the lamp but if it detects a vehicle or human the lamp remain brightened. The microcontroller uses the ultrasonic sensor to detect object and the PIR sensor to detect human. The RF module is used for communication between the microcontrollers to inform each other the presence of vehicle or human.  
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  Notes Approved no  
  Call Number IDA @ intern @ Serial 2971  
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Author Kobler, R. ( url  openurl
  Title (up) Die Lichtverschmutzung in der Schweiz. Mögliche Auswirkungen und praktische Lösungsansätze Type Journal Article
  Year 2002 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Lighting  
  Abstract  
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  Notes Approved no  
  Call Number LoNNe @ kagoburian @ Serial 641  
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Author Fonken, L.K.; Aubrecht, T.G.; Melendez-Fernandez, O.H.; Weil, Z.M.; Nelson, R.J. url  doi
openurl 
  Title (up) Dim light at night disrupts molecular circadian rhythms and increases body weight Type Journal Article
  Year 2013 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume 28 Issue 4 Pages 262-271  
  Keywords Animals; Blood Glucose/metabolism; Body Weight/*physiology; CLOCK Proteins/biosynthesis/genetics; Circadian Rhythm/*physiology; Corticosterone/metabolism; Feeding Behavior/physiology; Immunohistochemistry; Light; *Lighting; Male; Mice; Motor Activity; Polymerase Chain Reaction; Suprachiasmatic Nucleus/metabolism/physiology; clock genes; feeding rhythm; light pollution; obesity  
  Abstract With the exception of high latitudes, life has evolved under bright days and dark nights. Most organisms have developed endogenously driven circadian rhythms that are synchronized to this daily light/dark cycle. In recent years, humans have shifted away from the naturally occurring solar light cycle in favor of artificial and sometimes irregular light schedules produced by electric lighting. Exposure to unnatural light cycles is increasingly associated with obesity and metabolic syndrome; however, the means by which environmental lighting alters metabolism are poorly understood. Thus, we exposed mice to dim light at night and investigated changes in the circadian system and metabolism. Here we report that exposure to ecologically relevant levels of dim (5 lux) light at night altered core circadian clock rhythms in the hypothalamus at both the gene and protein level. Circadian rhythms in clock expression persisted during light at night; however, the amplitude of Per1 and Per2 rhythms was attenuated in the hypothalamus. Circadian oscillations were also altered in peripheral tissues critical for metabolic regulation. Exposure to dimly illuminated, as compared to dark, nights decreased the rhythmic expression in all but one of the core circadian clock genes assessed in the liver. Additionally, mice exposed to dim light at night attenuated Rev-Erb expression in the liver and adipose tissue. Changes in the circadian clock were associated with temporal alterations in feeding behavior and increased weight gain. These results are significant because they provide evidence that mild changes in environmental lighting can alter circadian and metabolic function. Detailed analysis of temporal changes induced by nighttime light exposure may provide insight into the onset and progression of obesity and metabolic syndrome, as well as other disorders involving sleep and circadian rhythm disruption.  
  Address Department of Neuroscience and Institute for Behavioral Medicine Research, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA. fonken.1@osu.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0748-7304 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23929553; PMCID:PMC4033305 Approved no  
  Call Number IDA @ john @ Serial 28  
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