|   | 
Details
   web
Records
Author (down) Hampf, D.; Rowell, G.; Wild, N.; Sudholz, T.; Horns, D.; Tluczykont, M.
Title Measurement of night sky brightness in southern Australia Type Journal Article
Year 2011 Publication Advances in Space Research Abbreviated Journal Advances in Space Research
Volume 48 Issue 6 Pages 1017-1025
Keywords Observatories and site testing; Airglow and aurorae; Photometric, polarimetric, and spectroscopic instrumentation
Abstract Night sky brightness is a major source of noise both for Cherenkov telescopes as well as for wide-angle Cherenkov detectors. Therefore, it is important to know the level of night sky brightness at potential sites for future experiments.

The measurements of night sky brightness presented here were carried out at Fowler’s Gap, a research station in New South Wales, Australia, which is a potential site for the proposed TenTen Cherenkov telescope system and the planned wide-angle Cherenkov detector system HiSCORE.

A portable instrument was developed and measurements of the night sky brightness were taken in February and August 2010. Brightness levels were measured for a range of different sky regions and in various spectral bands.

The night sky brightness in the relevant wavelength regime for photomultipliers was found to be at the same level as measured in similar campaigns at the established Cherenkov telescope sites of Khomas, Namibia, and at La Palma. The brightness of dark regions in the sky is about 2 × 1012 photons/(s sr m2) between 300 nm and 650 nm, and up to four times brighter in bright regions of the sky towards the galactic plane. The brightness in V band is 21.6 magnitudes per arcsec2 in the dark regions. All brightness levels are averaged over the field of view of the instrument of about 1.3 × 10−3 sr.

The spectrum of the night sky brightness was found to be dominated by longer wavelengths, which allows to apply filters to separate the night sky brightness from the blue Cherenkov light. The possible gain in the signal to noise ratio was found to be up to 1.2, assuming an ideal low-pass filter.
Address Department of Physics, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0273-1177 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 189
Permanent link to this record
 

 
Author (down) Gu, Y., Uprety, S., Blonski, S., Zhang, B., & Cao, C.
Title Improved algorithm for determining the Visible Infrared Imaging Radiometer Suite Day/Night Band high-gain stage dark offset free from light contamination Type Journal Article
Year 2019 Publication Applied Optics Abbreviated Journal
Volume 58 Issue 6 Pages 1400-1407
Keywords Remote Sensing; Instrumentation
Abstract Dark offset is one of the key parameters for Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) high-gain stage (HGS) radiometric calibration, whose accuracy strongly impacts applications of DNB low-light detection for Earth observation at nighttime. Currently, DNB observation of the VIIRS onboard calibrator blackbody (OBCBB) view, together with its observation of deep space during the spacecraft pitch maneuver performed early in the mission, has been used to compute the HGS dark offset continuously. However, the relationship between the DNB OBCBB data and the Earth view (EV) data is unclear due to electronic timing differences between these two views. It is questionable whether the DNB OBCBB data can monitor the EV HGS dark offset change. Through comprehensive analysis of the DNB OBCBB data and EV data acquired from the monthly special acquisitions known as the VIIRS recommended operating procedures (VROPs), we have shown that the OBCBB data can only track the dark current component of the DNB HGS EV dark offset, instead of the total dark offset. The DNB observation of deep space during the spacecraft pitch maneuver was also contaminated by starlight. With such background, in this paper we propose an improved algorithm for determining the DNB HGS dark offset. By combined use of the DNB OBCBB data and the DNB VROP data, the generated DNB HGS dark offset is both free from light contamination and capable of tracking continuous drift. The improved algorithm could potentially improve the DNB radiometric performance at low radiance level. Our results provide a solid theoretical basis for dark offset calibration of the VIIRS DNB onboard Suomi National Polar-Orbiting Partnership satellite and the following Joint Polar Satellite System satellites.
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 Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ intern @ Serial 2358
Permanent link to this record
 

 
Author (down) Gaydecki, P.
Title Automated moth flight analysis in the vicinity of artificial light Type Journal Article
Year 2018 Publication Bulletin of Entomological Research Abbreviated Journal Bull Entomol Res
Volume 109 Issue 1 Pages 127-140
Keywords Instrumentation; Animals
Abstract Instrumentation and software for the automated analysis of insect flight trajectories is described, intended for quantifying the behavioural dynamics of moths in the vicinity of artificial light. For its time, this moth imaging system was relatively advanced and revealed hitherto undocumented insights into moth flight behaviour. The illumination source comprised a 125 W mercury vapour light, operating in the visible and near ultraviolet wavelengths, mounted on top of a mobile telescopic mast at heights of 5 and 7.1 m, depending upon the experiment. Moths were imaged in early September, at night and in field conditions, using a ground level video camera with associated optics including a heated steering mirror, wide angle lens and an electronic image intensifier. Moth flight coordinates were recorded at a rate of 50 images per second (fields) and transferred to a computer using a light pen (the only non-automated operation in the processing sequence). Software extracted ground speed vectors and, by instantaneous subtraction of wind speed data supplied by fast-response anemometers, the airspeed vectors. Accumulated density profiles of the track data revealed that moths spend most of their time at a radius of between 40 and 50 cm from the source, and rarely fly directly above it, from close range. Furthermore, the proportion of insects caught by the trap as a proportion of the number influenced by the light (and within the field of view of the camera) was very low; of 1600 individual tracks recorded over five nights, a total of only 12 were caught. Although trap efficiency is strongly dependent on trap height, time of night, season, moonlight and weather, the data analysis confirmed that moths do not exhibit straightforward positive phototaxis. In general, trajectory patterns become more complex with reduced distance from the illumination, with higher recorded values of speeds and angular velocities. However, these characteristics are further qualified by the direction of travel of the insect; the highest accelerations tended to occur when the insect was at close range, but moving away from the source. Rather than manifesting a simple positive phototaxis, the trajectories were suggestive of disorientation. Based on the data and the complex behavioural response, mathematical models were developed that described ideal density distribution in calm air and light wind speed conditions. The models did not offer a physiological hypothesis regarding the behavioural changes, but rather were tools for quantification and prediction. Since the time that the system was developed, instrumentation, computers and software have advanced considerably, allowing much more to be achieved at a small fraction of the original cost. Nevertheless, the analytical tools remain useful for automated trajectory analysis of airborne insects.
Address School of Electrical and Electronic Engineering, University of Manchester,Manchester M13 9PL,UK
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 Edition
ISSN 0007-4853 ISBN Medium
Area Expedition Conference
Notes PMID:29745349 Approved no
Call Number GFZ @ kyba @ Serial 1895
Permanent link to this record
 

 
Author (down) Gaston, K.J.
Title Sustainability: A green light for efficiency Type Journal Article
Year 2013 Publication Nature Abbreviated Journal Nature
Volume 497 Issue 7451 Pages 560-561
Keywords Editorial; Animals; Atmosphere/chemistry; Carbon Dioxide/analysis; Circadian Rhythm/physiology; Conservation of Energy Resources/economics/*methods/*trends; Global Warming/prevention & control; Humans; Lighting/*economics/instrumentation/statistics & numerical data/*trends; Public Health
Abstract
Address Environment and Sustainability Institute, University of Exeter, Penryn, UK. k.j.gaston@exeter.ac.uk
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 Edition
ISSN 0028-0836 ISBN Medium
Area Expedition Conference
Notes PMID:23719447 Approved no
Call Number LoNNe @ christopher.kyba @ Serial 459
Permanent link to this record
 

 
Author (down) Fiorentin, P.; Boscaro, F.
Title A method for measuring the light output of video advertising reproduced by LED billboards Type Journal Article
Year 2019 Publication Measurement Abbreviated Journal Measurement
Volume 138 Issue Pages 25-33
Keywords Lighting; Energy; Instrumentation; Planning; Light-emitting diode displays; Photometry; Video recording; Image analysis; CCD image sensors; Luminance; Glare
Abstract Improving knowledge of the light output of digital billboards is important to better assess their effect on driver distraction when they are installed along roads. In this work the emission of an LED based billboard is measured when playing advertising video-clips. In particular the average and the maximum values of the luminance are evaluated. The same video-clips are also analyzed when shown on an LCD monitor, aiming at separating the variability of the videos and of the playing device. The results allow to evaluate an utilization factor of the billboard: the videos have an average luminance around 11% and a peak luminance of 35% of the maximum luminance obtainable from the billboard. The power consumption of the billboard is measured, aside the photometric analysis. The luminance of the device are found linearly dependent on both the power and the effective current absorbed by the device from the grid, with a discrepancy within 6%. It could be a useful information for billboard manufacturers to qualify their product when they do not own photometric instruments.
Address Department of Industrial Engineering, University of Padova, Padova, Italy; pietro.fiorentin(at)unipd.it
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 Edition
ISSN 0263-2241 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2214
Permanent link to this record