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Author Fiorentin, P.; Boscaro, F. url  doi
openurl 
  Title A method for measuring the light output of video advertising reproduced by LED billboards Type Journal Article
  Year 2019 Publication Measurement Abbreviated Journal Measurement  
  Volume (down) 138 Issue Pages 25-33  
  Keywords Lighting; Energy; Instrumentation; Planning; Light-emitting diode displays; Photometry; Video recording; Image analysis; CCD image sensors; Luminance; Glare  
  Abstract Improving knowledge of the light output of digital billboards is important to better assess their effect on driver distraction when they are installed along roads. In this work the emission of an LED based billboard is measured when playing advertising video-clips. In particular the average and the maximum values of the luminance are evaluated. The same video-clips are also analyzed when shown on an LCD monitor, aiming at separating the variability of the videos and of the playing device. The results allow to evaluate an utilization factor of the billboard: the videos have an average luminance around 11% and a peak luminance of 35% of the maximum luminance obtainable from the billboard. The power consumption of the billboard is measured, aside the photometric analysis. The luminance of the device are found linearly dependent on both the power and the effective current absorbed by the device from the grid, with a discrepancy within 6%. It could be a useful information for billboard manufacturers to qualify their product when they do not own photometric instruments.  
  Address Department of Industrial Engineering, University of Padova, Padova, Italy; pietro.fiorentin(at)unipd.it  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0263-2241 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2214  
Permanent link to this record
 

 
Author BjÖRnberg, T.K.S.; Wilbur, K.M. url  doi
openurl 
  Title Copepod Phototaxis And Vertical Migration Influenced By Xanthene Dyes Type Journal Article
  Year 1968 Publication The Biological Bulletin Abbreviated Journal The Biological Bulletin  
  Volume (down) 134 Issue 3 Pages 398-410  
  Keywords Animals  
  Abstract 1. Phototaxis of the copepods Paracalanus crassirostris, Calanopia americana, and Acartia lillijeborgi has been measured by determining the percentage of a population moving toward or away from a point source of light per unit time. Quantitative differences in positive phototaxis were found between the species. Photopositive responses differed during the day and night in Acartia but not in Paracalanus and Calanopia.

2. Rhodamine B (8.4 x 10-6 M) brought about the following effects: (a) Locomotor activity was reversibly inhibited in all species. (b) Photopositive responses were increased in Calanopia and Acartia but decreased in Paracalanus. (c) The difference between day and night responses to a point source of light was abolished in Acartia and induced in Calanopia. (d) Somersaulting was induced in Paracalanus but not in the other species.

3. Pyronine B (8.4 x 10-6 M) also decreased locomotor activity. Fluorescein sodium (1.1 x 10-5 M and 1.1 x 10-4 M) was without significant effect.

4. Paracalanus, Calanopia, and Acartia exhibited characteristically distinct diurnal migratory cycles in vertical cylinders, which correlated well with behavior in natural waters. Calanopia and Acartia migrated to the bottom in the daylight whereas Paracalanus and young forms of Acartia were widely distributed vertically during daylight. Specimens of Calanopia and Acartia kept in the dark did not migrate.

5. The effects of rhodamine B (8.4 x 10-6 M) on vertical migration depended upon species, developmental stage, and time of day. In general, rhodamine increased the concentration of animals at the surface at night and at the bottom in daylight. Fluorescein sodium (1.1 x 10-5 M and 1.1 x 10-4 M) had little effect on vertical migration.

6. The effectiveness of rhodamine B and pyronine B is probably related to the presence of diethylamine groups lacking in fluorescein.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-3185 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2469  
Permanent link to this record
 

 
Author Zhu, X.; Guo, X.; Zhang, J.; Liu, J.; Jiang, F. url  doi
openurl 
  Title Phosphor-free, color-mixed, and efficient illuminant: Multi-chip packaged LEDs for optimizing blue light hazard and non-visual biological effects Type Journal Article
  Year 2020 Publication Optics and Lasers in Engineering Abbreviated Journal Optics and Lasers in Engineering  
  Volume (down) 134 Issue Pages 106174  
  Keywords Lighting; Human Health  
  Abstract Currently many evaluation models on the photobiological effects (PBE) of light sources do not consider the influence of age and luminance on the pupil diameter, which affects the light radiation intensity on the human retina. In this study, the pupil diameter is taken into consideration when evaluating the PBE of several light sources. Moreover, the correction factor M is proposed. The blue light hazard (BLH) efficacy and the circadian rhythm (CR) effects of the daylight at dusk, together with three indoor light sources with a correlated color temperature (CCT) of about 3000 K were evaluated by using a corrected evaluation model. The results show that an incandescent lamp is more photobiologically friendly for humans, despite being inefficient. Based on high wall-plug efficiency (WPE) GaN-based yellow (565 nm, 24.3%@20 A/cm2) and green (522 nm, 41.3%@20 A/cm2) LEDs on silicon substrate, incandescent-like spectrum and phosphor-free color-mixed white LEDs (CM-LEDs) with a general color rendering index (CRI) of 94, a CCT of 2866 K, and an efficiency of 131 lm/W were manufactured by mixing blue, cyan, green, yellow and red LEDs. The PBE evaluation results of such CM-LEDs are superior to those of an incandescent lamp. Moreover, blue light free and candlelight-toned LEDs with an efficiency of 120.3 lm/W, a general CRI of 84, a special CRI R9 of 93.3, and a CCT of 1810 K were fabricated by mixing yellow and red LEDs (R&Y-mixed LEDs). The R&Y-mixed LEDs show no blue light weighted quantities and have a weaker influence on the CR shift. They are photobiologically friendly for humans and suitable for nocturnal indoor and outdoor lighting environments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0143-8166 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2983  
Permanent link to this record
 

 
Author Cochard, P.; Galstian, T.; Cloutier, C. url  doi
openurl 
  Title The proportion of blue light affects parasitoid wasp behavior in LED-extended photoperiod in greenhouses: Increased parasitism and offspring sex ratio bias Type Journal Article
  Year 2019 Publication Biological Control Abbreviated Journal Biological Control  
  Volume (down) 133 Issue Pages 9-17  
  Keywords Animals  
  Abstract The increasing use of specific wavelengths involving light-emitting diodes (LEDs) under greenhouses enables to overcome the lack of light during winter months, helping crops photosynthesis or vegetative growth. However, modification of the light environment as well as the photoperiod may also alter directly or indirectly the activity of both beneficial and pest insects that depend on plants. Here, we submitted the parasitic wasp Aphidius ervi and its main host the pea aphid, to 4 ratios of red(R): blue(B) LEDs used to lengthen the photoperiod inside a growth chamber. We recorded the parasitism rate of aphids and the sex ratio of newly emerged wasps to evaluate if A. ervi could remain an efficient biological control agent under modified light environments. We found that increasing the 8 h of photophase to 16 h by supplementing with R/B LEDs increased the daily parasitic activity of the wasp as well as their egg laying behavior. Under the 100R light supplement, about 80% of the emerged adults were males, against 50% under 25R:75B light treatment. These results indicate that A. ervi remains a good biological control agent when the light environment is modified. However, the use of red light to extend the photophase has the potential to negatively affect population dynamics of these parasitoids due to its male-bias impact on the sex ratio.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1049-9644 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2253  
Permanent link to this record
 

 
Author Obayashi, K.; Yamagami, Y.; Tatsumi, S.; Kurumatani, N.; Saeki, K. url  doi
openurl 
  Title Indoor light pollution and progression of carotid atherosclerosis: A longitudinal study of the HEIJO-KYO cohort Type Journal Article
  Year 2019 Publication Environment International Abbreviated Journal Environment International  
  Volume (down) 133 Issue Pages 105184  
  Keywords Human Health  
  Abstract Exposure to light at inappropriate times in relation to the solar cycle can disturb circadian endocrine and metabolic rhythms. Previous studies have suggested an association between light exposure at night (LAN) and obesity, an important risk factor of atherosclerosis, although it remains unclear whether LAN associates with progression of atherosclerosis. To evaluate the longitudinal association between bedroom LAN intensity and progression of carotid atherosclerosis, light intensity in the bedroom at baseline and carotid artery intima-media thickness (IMT) at baseline and follow-up were measured in 989 elderly participants (945 at baseline and 780 at a median follow-up time of 34 months). The mean age of the participants was 71.4 ± 6.9 years. The average mean and maximal carotid IMT at baseline were 0.88 ± 0.15 and 1.10 ± 0.32 mm, respectively. The median intensity of bedroom LAN was 0.68 lx (IQR, 0.07–3.29). In multivariable analysis adjusted for potential confounders, the highest LAN group exhibited a significant increase in mean carotid IMT (adjusted β, 0.028; 95% CI, 0.005–0.052; P = 0.019) compared with the lowest LAN quartile group. A similar relationship was found between LAN and maximal carotid IMT (adjusted β, 0.083; 95% CI, 0.037–0.129; P < 0.001).

In conclusion, we found a clear and significant association between bedroom LAN intensity and progression of subclinical carotid atherosclerosis, which was independent of known risk factors for atherosclerosis, including age, obesity, smoking, economic status, hypertension, and diabetes. Indoor light pollution may be a potential risk factor for atherosclerosis in the general population.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0160-4120 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2706  
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