scholarly journals Multiple night-time light-emitting diode lighting strategies impact grassland invertebrate assemblages

2017 ◽  
Vol 23 (7) ◽  
pp. 2641-2648 ◽  
Author(s):  
Thomas W. Davies ◽  
Jonathan Bennie ◽  
Dave Cruse ◽  
Dan Blumgart ◽  
Richard Inger ◽  
...  
2016 ◽  
Vol 50 (2) ◽  
pp. 266-281 ◽  
Author(s):  
A Shahar ◽  
R Brémond ◽  
C Villa

Road delineation treatments enhance the ability of drivers to control their vehicle safely on winding roads. A simulator experiment compared night-time driving on a country road under three conditions: on an unlit road, on a road illuminated on curves by typical road luminaires, and on a road with an active lane delineation application, where self-luminous road studs are turned on to outline the lane and road edges as the driver approaches and passes the curves. The unlit condition induces greater lateral position variability and longer crossovers relative to the studs condition, demonstrating better lateral vehicle control in the latter. The luminaires condition induce greater lateral position variability in left curves, and longer crossovers in right curves, relative to the studs condition, which also demonstrates a better lateral vehicle control in the studs condition. At a subjective level, the participants perceived both the studs condition and the luminaires condition as safer, more comfortable and allowing better control than the unlit road. It was concluded that the tested application enhanced the ability of drivers to control the virtual car, as compared to an unlit road or road lighting.


Author(s):  
Adrian Sandt ◽  
Haitham Al-Deek

Limited access facility wrong-way driving (WWD) crashes are typically more severe than other crashes. Deploying advanced WWD countermeasures, such as rectangular flashing beacon (RFB) and light-emitting diode (LED) technologies, at exit ramps can reduce WWD crashes, injuries, and fatalities. No previous research has developed a methodology to quantify the potential fatality and injury savings because of future countermeasure deployments. This paper developed such a methodology and applied it to Florida’s Turnpike Enterprise (FTE) toll road network. From 2011–2016, there were 53 FTE WWD crashes, resulting in 16 fatalities and annual injury costs of $37 million. The proportion of these crashes occurring during night-time was 87%. RFB and LED life-cycle injury savings and costs were determined for all 216 FTE exits. The total savings were $424 million for RFBs (benefit–cost [B/C] ratio of 23.20) and $144 million for LEDs (B/C ratio of 13.13). Deploying countermeasures at the 103 exits with the highest B/C ratios would provide 70% of the total possible savings by equipping 40% of the ramps. For the same capital investment, RFBs provide more savings than LEDs. Spending $1 million to deploy RFBs will provide similar savings as spending $3.4 million to deploy LEDs. Evaluating the existing FTE RFB and LED ramps shows that RFBs are more effective at night-time and can provide three times the savings of LEDs. The results of this paper show the improved performance of RFBs over LEDs and provide an example that other agencies could follow to identify savings and cost-effectively deploy advanced WWD countermeasures.


2021 ◽  
Vol 13 (16) ◽  
pp. 3311
Author(s):  
Alejandro Sánchez de Miguel ◽  
Jonathan Bennie ◽  
Emma Rosenfeld ◽  
Simon Dzurjak ◽  
Kevin J. Gaston

The global spread of artificial light is eroding the natural night-time environment. The estimation of the pattern and rate of growth of light pollution on multi-decadal scales has nonetheless proven challenging. Here we show that the power of global satellite observable light emissions increased from 1992 to 2017 by at least 49%. We estimate the hidden impact of the transition to solid-state light-emitting diode (LED) technology, which increases emissions at visible wavelengths undetectable to existing satellite sensors, suggesting that the true increase in radiance in the visible spectrum may be as high as globally 270% and 400% on specific regions. These dynamics vary by region, but there is limited evidence that advances in lighting technology have led to decreased emissions.


2015 ◽  
Vol 11 (4) ◽  
pp. 20150080 ◽  
Author(s):  
Thomas W. Davies ◽  
Matthew Coleman ◽  
Katherine M. Griffith ◽  
Stuart R. Jenkins

Marine benthic communities face multiple anthropogenic pressures that compromise the future of some of the most biodiverse and functionally important ecosystems in the world. Yet one of the pressures these ecosystems face, night-time lighting, remains unstudied. Light is an important cue in guiding the settlement of invertebrate larvae, and altering natural regimes of nocturnal illumination could modify patterns of recruitment among sessile epifauna. We present the first evidence of night-time lighting changing the composition of temperate epifaunal marine invertebrate communities. Illuminating settlement surfaces with white light-emitting diode lighting at night, to levels experienced by these communities locally, both inhibited and encouraged the colonization of 39% of the taxa analysed, including three sessile and two mobile species. Our results indicate that ecological light pollution from coastal development, shipping and offshore infrastructure could be changing the composition of marine epifaunal communities.


2020 ◽  
pp. 144-148

Chaos synchronization of delayed quantum dot light emitting diode has been studied theortetically which are coupled via the unidirectional and bidirectional. at synchronization of chaotic, The dynamics is identical with delayed optical feedback for those coupling methods. Depending on the coupling parameters and delay time the system exhibits complete synchronization, . Under proper conditions, the receiver quantum dot light emitting diode can be satisfactorily synchronized with the transmitter quantum dot light emitting diode due to the optical feedback effect.


PIERS Online ◽  
2007 ◽  
Vol 3 (6) ◽  
pp. 821-824 ◽  
Author(s):  
Chien-Chang Tseng ◽  
Liang-Wen Ji ◽  
Yu Sheng Tsai ◽  
Fuh-Shyang Juang

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