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de Meester, J., & Storch, T. (2020). Optimized Performance Parameters for Nighttime Multispectral Satellite Imagery to Analyze Lightings in Urban Areas. Sensors (Basel), 20(11).
Abstract: Contrary to its daytime counterpart, nighttime visible and near infrared (VIS/NIR) satellite imagery is limited in both spectral and spatial resolution. Nevertheless, the relevance of such systems is unquestioned with applications to, e.g., examine urban areas, derive light pollution, and estimate energy consumption. To determine optimal spectral bands together with required radiometric and spatial resolution, at-sensor radiances are simulated based on combinations of lamp spectra with typical luminances according to lighting standards, surface reflectances, and radiative transfers for the consideration of atmospheric effects. Various band combinations are evaluated for their ability to differentiate between lighting types and to estimate the important lighting parameters: efficacy to produce visible light, percentage of emissions attributable to the blue part of the spectrum, and assessment of the perceived color of radiation sources. The selected bands are located in the green, blue, yellow-orange, near infrared, and red parts of the spectrum and include one panchromatic band. However, these nighttime bands tailored to artificial light emissions differ significantly from the typical daytime bands focusing on surface reflectances. Compared to existing or proposed nighttime or daytime satellites, the recommended characteristics improve, e.g., classification of lighting types by >10%. The simulations illustrate the feasible improvements in nocturnal VIS/NIR remote sensing which will lead to advanced applications.
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Scott, R. (1980). THE RELATIONSHIP BETWEEN ROAD LIGHTING QUALITY AND ACCIDENT FREQUENCY – TRRL LABORATORY REPORT 929.
Abstract: many studies have related changes in accident frequency to the presence of street lighting, and a few have examined its variation over a range of lighting quality, as measured by illuminance. this investigation attempts to find which of several measures of lighting (describing quantity – as represented by luminance or illuminance – uniformity and glare) most clearly explain variations in accident frequency. about 100 lit sites, almost all in built-up areas, were measured for lighting quality in dry-road conditions. the lighting variables measured were related to the dark:day ratios of accident frequency for the same sites. the strongest relationship found was that for average road surface luminance: in the range 0.5-2.0 candelas/m2, it is estimated that an increase of 1 cd/m2 is associated with a 35 per cent lower accident ratio. other measures of luminance and illuminance were also found to be related to accident ratio (and to each other), but not as clearly as was average road luminance, which is therefore the preferred explanatory variable. analysis of pedestrian and non-pedestrian accidents separately did not reveal a relationship between the former and lighting quality. in contrast, non-pedestrian accidents showed similar relationships to those for all accidents, with the addition of a possible relationship with overall uniformity of luminance.(a)
Keywords: Lighting; quality; accident rate; accident; frequency; luminance; glare; uniformity; urban area; daylight; darkness; surfacing; pedestrian
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Tan, M. (2016). Use of an inside buffer method to extract the extent of urban areas from DMSP/OLS night-time light data in North China. GIScience & Remote Sensing, 53(4), 444–458.
Abstract: Defense Meteorological Satellite Program (DMSP)/Operational Linescan System (OLS) night-time imagery provides a valuable data source for mapping urban areas. However, the spatial extents of large cities are often over-estimated because of the effect of over-glow from night-time light if a fixed thresholding technique is used. In the work reported here, an inside buffer method was developed to solve this issue. The method is based on the fact that the area over-estimated is proportional to the extent of the lit area if a fixed threshold is used to extract urban areas in a region/county. Using this method, the extents of urban areas in North China were extracted and validated by interpretations from Landsat Thematic Mapper images. The results showed that the lit areas had a significant linear relationship with the urban areas for 120 representative cities in North China in 2000, with an R2 value of over 0.95. This demonstrates that the inside buffer method can be used to extract urban areas. The validation results showed that the inside buffer model developed in 2000 can be directly used to extract the extent of urban areas using more recent night-time light imagery. This is of great value for the timely updating of urban area databases in large regions or countries.
Keywords: Remote Sensing; DMSP-OLS; OLS; DMSP; inside buffer model; China; over-glow; urban areas; urban; urbanism
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