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Author Bagan, H.; Borjigin, H.; Yamagata, Y.
Title Assessing nighttime lights for mapping the urban areas of 50 cities across the globe Type Journal Article
Year 2018 Publication Environment and Planning B: Urban Analytics and City Science Abbreviated Journal Environment and Planning B: Urban Analytics and City Science
Volume Issue Pages 2399808317752926
Keywords Remote Sensing
Abstract Nighttime data from the Defense Meteorological Satellite Program Operational Linescan System have been widely used to map urban/built-up areas (hereafter referred to as “built-up area”), but to date there has not been a geographically comprehensive evaluation of the effectiveness of using nighttime lights data to map urban areas. We created accurate, convenient, and scalable grid cells based on Defense Meteorological Satellite Program/Operational Linescan System nighttime light pixels. We then calculated the density of Landsat-derived built-up areas within each grid cell. We explored the relationship between Defense Meteorological Satellite Program/Operational Linescan System nighttime lights data and the density of built-up areas to assess the utility of nighttime lights for mapping urban areas in 50 cities across the globe. We found that the brightness of nighttime lights was only in moderate agreement with the density of built-up areas; moreover, correlations between nighttime lights and Landsat-derived built-up areas were weak. Even in relatively sparsely populated urban regions (where the density of the built-up area is less than 20%), the highest correlation coefficient (R2) was only 0.4. Furthermore, nighttime lights showed lighted areas that extended beyond the area of large cities, and nighttime lights reduced the area of small cities. The results suggest that it is difficult to use the regression model to calibrate the Defense Meteorological Satellite Program/Operational Linescan System nighttime lights to fit urban built up areas.
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 (up) Edition
ISSN 2399-8083 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kyba @; GFZ @ kyba @ Serial 1795
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Author Bará, S.; Escofet, J.
Title On lamps, walls, and eyes: The spectral radiance field and the evaluation of light pollution indoors Type Journal Article
Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal J of Quant Spect and Rad Trans
Volume 205 Issue Pages 267-277
Keywords Instrumentation; Light pollution; Artificial light at night; Light field; Radiance field; Radiometry; Photometry
Abstract Light plays a key role in the regulation of different physiological processes, through several visual and non-visual retinal phototransduction channels whose basic features are being unveiled by recent research. The growing body of evidence on the significance of these effects has sparked a renewed interest in the determination of the light field at the entrance pupil of the eye in indoor spaces. Since photic interactions are strongly wavelength-dependent, a significant effort is being devoted to assess the relative merits of the spectra of the different types of light sources available for use at home and in the workplace. The spectral content of the light reaching the observer eyes in indoor spaces, however, does not depend exclusively on the sources: it is partially modulated by the spectral reflectance of the walls and surrounding surfaces, through the multiple reflections of the light beams along all possible paths from the source to the observer. This modulation can modify significantly the non-visual photic inputs that would be produced by the lamps alone, and opens the way for controlling—to a certain extent—the subject's exposure to different regions of the optical spectrum. In this work we evaluate the expected magnitude of this effect and we show that, for factorizable sources, the spectral modulation can be conveniently described in terms of a set of effective filter-like functions that provide useful insights for lighting design and light pollution assessment. The radiance field also provides a suitable bridge between indoor and outdoor light pollution studies.
Address Área de Óptica, Departamento de Física Aplicada, Universidade de Santiago de Compostela, Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es
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 (up) Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 2163
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Author Wu, W.; Zhao, H.; Jiang, S.
Title A Zipf's Law-Based Method for Mapping Urban Areas Using NPP-VIIRS Nighttime Light Data Type Journal Article
Year 2018 Publication Remote Sensing Abbreviated Journal Remote Sensing
Volume 10 Issue 1 Pages 130
Keywords Remote Sensing
Abstract A significant difficulty in urban studies is obtaining urban areas. Nighttime light (NTL) data provide efficient approaches to map urban areas. Previous methods have utilized visual particularities of cities with ancillary data to obtain the optimal thresholds. How cities behave differently from rural areas should be considered. A Zipf’s law-based method is proposed to bootstrap the optimal threshold based on the statistical properties of a Zipf’s law model on continuous thresholds at the country scale. In our method, the Zipf’s law model is utilized to quantify fractal, self-organized, and agglomeration behaviors of cities. The three-phase cluster dynamics are discovered and the abrupt transition between Phase 1 and Phase 2 denotes the rural-urban demarcation point. The urban areas are derived by the proposed method from the Suomi National Polar-Orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS) NTL data in 2013 in China. An accuracy assessment is conducted to compare it with the GlobeLand30-2010 data and the overall accuracy has directly confirmed the effectiveness of the method. The validation using point of interest (POI) data verifies that the urban areas show strong responses to social interactions and production with R2 values of 0.91 and 0.92, respectively, implying that the city areas extracted by our method can be a proxy for human activities. Comparisons with existing methods validate the effectiveness and high degree of automation of the proposed method in mapping urban areas at the country level. According to our analyses, the Zipf’s law-based method shows great potential to provide a universal criterion to map urban areas from the perspective of the behaviors of urban systems without ancillary data, and a valuable tool for spatial and temporal urban studies.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue (up) Edition
ISSN 2072-4292 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kyba @ Serial 1797
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Author Nagare, R.; Plitnick, B.; Figueiro, M.
Title Does the iPad Night Shift mode reduce melatonin suppression? Type Journal Article
Year 2018 Publication Lighting Research & Technology Abbreviated Journal Lighting Research & Technology
Volume 51 Issue 3 Pages 373-383
Keywords Human Health
Abstract The increased use of self-luminous displays, especially in the evening prior to bedtime, has been associated with melatonin suppression, delayed sleep and sleep curtailment. The present study set out to investigate whether the Night Shift application provided by Apple Inc. for use on its portable electronic devices is effective for reducing acute melatonin suppression, a well-established marker of circadian phase. Participants experienced four experimental conditions: a dim light control, a high circadian stimulus true positive intervention and two Night Shift interventions delivering low and high correlated colour temperature light from the devices. Melatonin suppression did not significantly differ between the two Night Shift interventions, which indicates that changing the spectral composition of self-luminous displays without changing their brightness settings may be insufficient for preventing impacts on melatonin suppression.
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 (up) Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kyba @; GFZ @ kyba @ Serial 1798
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Author Foster, J.J.; Smolka, J.; Nilsson, D.-E.; Dacke, M.
Title How animals follow the stars Type Journal Article
Year 2018 Publication Proceedings. Biological Sciences Abbreviated Journal Proc Biol Sci
Volume 285 Issue 1871 Pages
Keywords Vision; Animals
Abstract Throughout history, the stars have provided humans with ever more information about our world, enabling increasingly accurate systems of navigation in addition to fuelling some of the greatest scientific controversies. What information animals have evolved to extract from a starry sky and how they do so, is a topic of study that combines the practical and theoretical challenges faced by both astronomers and field biologists. While a number of animal species have been demonstrated to use the stars as a source of directional information, the strategies that these animals use to convert this complex and variable pattern of dim-light points into a reliable 'stellar orientation' cue have been more difficult to ascertain. In this review, we assess the stars as a visual stimulus that conveys directional information, and compare the bodies of evidence available for the different stellar orientation strategies proposed to date. In this context, we also introduce new technologies that may aid in the study of stellar orientation, and suggest how field experiments may be used to characterize the mechanisms underlying stellar orientation.
Address Department of Biology, Lund University, Solvegatan 35, Lund 223 62, Sweden
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue (up) Edition
ISSN 0962-8452 ISBN Medium
Area Expedition Conference
Notes PMID:29367394 Approved no
Call Number LoNNe @ kyba @ Serial 1802
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