A large-scale real-life crowd steering experiment via arrow-like stimuli

We introduce "Moving Light": an unprecedented real-life crowd steering experiment that involved about 140.000 participants among the visitors of the Glow 2017 Light Festival (Eindhoven, NL). Moving Light targets one outstanding question of paramount societal and technological importance: "can we seamlessly and systematically influence routing decisions in pedestrian crowds?" Establishing effective crowd steering methods is extremely relevant in the context of crowd management, e.g. when it comes to keeping floor usage within safety limits (e.g. during public events with high attendance) or at designated comfort levels (e.g. in leisure areas). In the Moving Light setup, visitors walking in a corridor face a choice between two symmetric exits defined by a large central obstacle. Stimuli, such as arrows, alternate at random and perturb the symmetry of the environment to bias choices. While visitors move in the experiment, they are tracked with high space and time resolution, such that the efficiency of each stimulus at steering individual routing decisions can be accurately evaluated a posteriori. In this contribution, we first describe the measurement concept in the Moving Light experiment and then we investigate quantitatively the steering capability of arrow indications.Comment: 8 page

A large-scale real-life crowd steering experiment via arrow-like stimuli

We introduce “Moving Light”: an unprecedented real-life crowd steering experiment that involved about 140.000 participants among the visitors of the Glow 2017 Light Festival (Eindhoven, NL). Moving Light targets one outstanding question of paramount societal and technological importance: “can we seamlessly and systematically influence routing decisions in pedestrian crowds?” Establishing effective crowd steering methods is extremely relevant in the context of crowd management, e.g. when it comes to keeping floor usage within safety limits (e.g. during public events with high attendance) or at designated comfort levels (e.g. in leisure areas). In the Moving Light setup, visitors walking in a corridor face a choice between two symmetric exits defined by a large central obstacle. Stimuli, such as arrows, alternate at random and perturb the symmetry of the environment to bias choices. While visitors move in the experiment, they are tracked with high space and time resolution, such that the efficiency of each stimulus at steering individual routing decisions can be accurately evaluated a posteriori. In this contribution, we first describe the measurement concept in the Moving Light experiment and then we investigate quantitatively the steering capability of arrow indications

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Glare quantification for indoor volleyball

Sports facilities all over the world apply LED lighting. The combination of high luminance and small luminous surfaces causes a high probability of glare and LED lighting contains these specifications. There are specific situations for which validated glare models exist, such as offices or outdoor soccer fields, although indoor sports facilities are not one of them. Additionally, we do not know the degree to which lighting may impact athletes’ performance. Contradictory research exists on whether glare decreases task performance, and whether any decrease is due to discomfort glare or disability glare. In the current research, objective performance measurements were conducted on a volleyball court with both amateur and professional athletes from the Dutch national indoor volleyball competition—the Eredivisie. An eye tracker was used to see if gaze data contributed to a better understanding of performance or the subjective experience of glare. The results show that athletes’ performance was not decreased due to glare, although the subjective experiences, measured by discomfort and non-acceptance, increased significantly. The current unified glare rating (UGR) glare model has a strong correlation with the discomfort findings, although the combination of source luminance and background luminance predicts discomfort and non-acceptance even better. This paper demonstrates that existing glare models perform well for indoor sports environments

Glare quantification for indoor volleyball

\u3cp\u3eSports facilities all over the world apply LED lighting. The combination of high luminance and small luminous surfaces causes a high probability of glare and LED lighting contains these specifications. There are specific situations for which validated glare models exist, such as offices or outdoor soccer fields, although indoor sports facilities are not one of them. Additionally, we do not know the degree to which lighting may impact athletes’ performance. Contradictory research exists on whether glare decreases task performance, and whether any decrease is due to discomfort glare or disability glare. In the current research, objective performance measurements were conducted on a volleyball court with both amateur and professional athletes from the Dutch national indoor volleyball competition—the Eredivisie. An eye tracker was used to see if gaze data contributed to a better understanding of performance or the subjective experience of glare. The results show that athletes’ performance was not decreased due to glare, although the subjective experiences, measured by discomfort and non-acceptance, increased significantly. The current unified glare rating (UGR) glare model has a strong correlation with the discomfort findings, although the combination of source luminance and background luminance predicts discomfort and non-acceptance even better. This paper demonstrates that existing glare models perform well for indoor sports environments.\u3c/p\u3

A psychophysical model for visual discomfort based on receptive fields

© 2016, © The Chartered Institution of Building Services Engineers 2016. Visual discomfort is predicted from a luminance map with a model based on the receptive field mechanism in the human eye. A centre-surround receptive field is described by a Difference of Gaussians. Eight commercially available office luminaires are assessed for visual discomfort in a paired comparison experiment. The correlation between the subjective data and the receptive field model is optimized for three factors: the centre Gaussian width, the surround Gaussian width and the centre-to-surround weighing factor (WF). A centre and surround visual angle of 0.53 and 2.19 min arc, respectively, and a WF of 0.87 result in a coefficient of determination of 0.77. The model is validated independently with magnitude estimation data obtaining a coefficient of determination of 0.82. Where the standard unified glare rating method fails (coefficient of determination of 0.45), the receptive field model ameliorates predictability for visual discomfort. The model based on receptive fields is promising to replace current standard glare metrics, specifically when non-uniform luminaires are to be evaluated.status: publishe

Behaviour of migrating toads under artificial lights differs from other phases of their life cycle

During annual spring migration in Western Europe many amphibians are killed by traffic when they cross roads moving to reproduction sites. Especially in urban settings these roads are often equipped with street lighting. The response of amphibians to this light during migration is however poorly known. Street lighting may attract migrating amphibians increasing the risk of being struck by traffic. Using experimental illumination we tested whether light affected the migration and if adjustment of the spectral composition could mitigate effects. Barriers used to catch toads and help them cross roads safely were divided in 25 meter long sections and these were illuminated with white, green or red light or kept dark. The number of toads caught in each section was counted. Common toads avoided sections of roads that were illuminated with white or green light but not red light. Street light thus affects migrating toads but not as expected and red light with low levels of short wavelength can be used to mitigate effects

Colors of attraction: Modeling insect flight to light behavior

Light sources attract nocturnal flying insects, but some lamps attract more insects than others. The relation between the properties of a light source and the number of attracted insects is, however, poorly understood. We developed a model to quantify the attractiveness of light sources based on the spectral output. This model is fitted using data from field experiments that compare a large number of different light sources. We validated this model using two additional datasets, one for all insects and one excluding the numerous Diptera. Our model facilitates the development and application of light sources that attract fewer insects without the need for extensive field tests and it can be used to correct for spectral composition when formulating hypotheses on the ecological impact of artificial light. In addition, we present a tool allowing the conversion of the spectral output of light sources to their relative insect attraction based on this model

Green Light for Nocturnally Migrating Birds

The nighttime sky is increasingly illuminated by artificial light sources. Although this ecological light pollution is damaging ecosystems throughout the world, the topic has received relatively little attention. Many nocturnally migrating birds die or lose a large amount of their energy reserves during migration as a result of encountering artificial light sources. This happens, for instance, in the North Sea, where large numbers of nocturnally migrating birds are attracted to the many offshore platforms. Our aim is to develop bird-friendly artificial lighting that meets human demands for safety but does not attract and disorient birds. Our current working hypothesis is that artificial light interferes with the magnetic compass of the birds, one of several orientation mechanisms and especially important during overcast nights. Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the spectrum for magnetic compass orientation, whereas red light (visible long-wavelength) disrupts magnetic orientation. We designed a field study to test if and how changing light color influenced migrating birds under field conditions. We found that nocturnally migrating birds were disoriented and attracted by red and white light (containing visible long-wavelength radiation), whereas they were clearly less disoriented by blue and green light (containing less or no visible long-wavelength radiation). This was especially the case on overcast nights. Our results clearly open perspective for the development of bird-friendly artificial lighting by manipulating wavelength characteristics. Preliminary results with an experimentally developed bird-friendly light source on an offshore platform are promising. What needs to be investigated is the impact of bird-friendly light on other organisms than birds