7 research outputs found

    Characterization of Imaging Luminance Measurement Devices (ILMDs)

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    CIE 244:2021This document describes the elements, function and characterization of imaging luminance measuring devices (ILMDs). Furthermore, the calibration of ILMDs is described and some guidelines for their use are provided. Using ILMDs the projection of the luminance distribution of a scene can be recorded and made available for further evaluation. In addition to a simple documentation of measurements, the geometrical assignment of the image points into the object coordinate system often allows more complex calculations by combining luminance, directional and, if necessary, solid angle information (e.g. for glare evaluation). In addition to the flexible evaluation option, it is possible to acquire a large number of measured values quickly and, if necessary, even synchronously. Furthermore, the type of evaluation can also be coupled to the image content, i.e. the image areas to be evaluated can be determined in the image either by their position within the image or by their luminance value

    Multiple Angle Observations Would Benefit Visible Band Remote Sensing Using Night Lights

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    The spatial and angular emission patterns of artificial and natural light emitted, scattered, and reflected from the Earth at night are far more complex than those for scattered and reflected solar radiation during daytime. In this commentary, we use examples to show that there is additional information contained in the angular distribution of emitted light. We argue that this information could be used to improve existing remote sensing retrievals based on night lights, and in some cases could make entirely new remote sensing analyses possible. This work will be challenging, so we hope this article will encourage researchers and funding agencies to pursue further study of how multi‐angle views can be analyzed or acquired

    Occupational electromagnetic spectrum hazards and the significance of artificial optical radiation: country report for Greece

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    Background: The electromagnetic spectrum spans over an enormous range from 0 up to more than 1020 Hz in the deep ionizing region, significant exposures exist in specific occupational environments. Between the ionizing and the electromagnetic fields (EMF) part of the spectrum, the ‘optical radiation’ (OR) region has specific properties. Comparative and concise evaluation enables action prioritization. Methods: Following the transposition and imple-mentation periods of the artificial optical radiation (AOR) and EMF European Directives, the Hellenic Ministry of Labour in collaboration with the Greek Atomic Energy Commission (EEAE) and the National Technical University of Athens, conducted thorough occupational exposure investigation in Greece. Using dedicated measuring equipment and procedures, the majority of EMF emitting installations in Greece and also AOR emitting installations including arc welding, lasers and PC monitors has been assessed. Results: Measurement results from occupational settings reveal that it is the non-coherent metal arc welding AOR that can pose even sub-second overexposures. Rare EMF overexposures are manageable and EMF concern is not justified. Maintenance procedures demand proper attention. Preliminary laser safety assessment reveals OHS gaps and potential eye and skin hazards. Blue light exposure from computer monitors is well below safety limits. Conclusions: This electromagnetic spectrum risk assessment conducted in Greece enables the justification of the real occupational hazards, in this sense: i) EMF exposure assessment has to be concentrated to maintenance procedures; ii) AOR measuring setups are challenging and standardized measurement procedures are missing, and iii) AOR overexposures from arc welding pose significant eye and skin hazards. © 2022, Mattioli 1885. All rights reserved

    Multiple Angle Observations Would Benefit Visible Band Remote Sensing Using Night Lights

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    The spatial and angular emission patterns of artificial and natural light emitted, scattered, and reflected from the Earth at night are far more complex than those for scattered and reflected solar radiation during daytime. In this commentary, we use examples to show that there is additional information contained in the angular distribution of emitted light. We argue that this information could be used to improve existing remote sensing retrievals based on night lights, and in some cases could make entirely new remote sensing analyses possible. This work will be challenging, so we hope this article will encourage researchers and funding agencies to pursue further study of how multi‐angle views can be analyzed or acquired.Plain Language Summary: When satellites take images of Earth, they usually do so from directly above (or as close to it as is reasonably possible). In this comment, we show that for studies that use imagery of Earth at night, it may be beneficial to take several images of the same area at different angles within a short period of time. For example, different types of lights shine in different directions (street lights usually shine down, while video advertisements shine sideways), and tall buildings can block the view of a street from some viewing angles. Additionally, since views from different directions pass through different amounts of air, imagery at multiple angles could be used to obtain information about Earth's atmosphere, and measure artificial and natural night sky brightness. The main point of the paper is to encourage researchers, funding agencies, and space agencies to think about what new possibilities could be achieved in the future with views of night lights at different angles.Key Points: Remote sensing using the visible band at night is more complex than during the daytime, especially due to the variety of artificial lights. Views of night lights intentionally taken from multiple angles provide several advantages over near‐nadir or circumstantial view geometries. Night lights remote sensing would benefit from greater consideration of the role viewing geometry plays in the observed radiance.EC H2020 H2020 Societal Challenges http://dx.doi.org/10.13039/100010676Helmholtz Association http://dx.doi.org/10.13039/501100009318Slovak Research and Development AgencyXunta de Galicia (Regional Government of Galicia) http://dx.doi.org/10.13039/501100010801National Aeronautics and Space Administration http://dx.doi.org/10.13039/100000104University of Hong Kong http://dx.doi.org/10.13039/501100003803Fonds de recherche du QuĂ©becEC Emprego, Assuntos Sociais e InclusĂŁo European Social Fund http://dx.doi.org/10.13039/501100004895Natural Environment Research Council http://dx.doi.org/10.13039/501100000270City of Cologne, German
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