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| Author | Wahl, F.; Kantermann, T.; Amft, O. | ||||
| Title | How much Light do you get? Estimating Daily Light Exposure using Smartphones | Type  |
Conference Article | ||
| Year | 2014 | Publication | Proceedings of the 2014 ACM International Symposium on Wearable Computers | Abbreviated Journal | Proc. of the 2014 ACM International Symposium on Wearable Computers |
| Volume | n/a | Issue | n/a | Pages | 43-46 |
| Keywords | Instrumentation; light exposure; context inference, light intensity; light intake; circadian clock; circadian rhythm; mobile sensing | ||||
| Abstract | We present an approach to estimate a persons light exposure using smartphones. We used web-sourced weather reports combined with smartphone light sensor data, time of day, and indoor/outdoor information, to estimate illuminance around the user throughout a day. Since light dominates every human’s circadian rhythm and influences the sleep-wake cycle, we developed a smartphone-based system that does not re- quire additional sensors for illuminance estimation. To evaluate our approach, we conducted a free-living study with 12 users, each carrying a smartphone, a head-mounted light reference sensor, and a wrist-worn light sensing device for six consecutive days. Estimated light values were compared to the head-mounted reference, the wrist-worn device and a mean value estimate. Our results show that illuminance could be estimated at less than 20% error for all study participants, outperforming the wrist-worn device. In 9 out of 12 participants the estimation deviated less than 10% from the reference measurements. | ||||
| Address | ACTLab, Chair of Sensor Technology, University of Passau (florian.wahl@uni-passau.de) | ||||
| Corporate Author | Thesis | ||||
| Publisher | ACM | Place of Publication | Editor | ||
| Language | English | Summary Language | English | Original Title | |
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| Series Volume | Series Issue | Edition | |||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | IDA @ john @ | Serial | 1206 | ||
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| Author | Allik, T.; Ramboyong, L.; Roberts, M.; Walters, M.; Soyka, T.; Dixon, R.; Cho, J. | ||||
| Title | Enhanced oil spill detection sensors in low-light environments | Type |
Conference Article | ||
| Year | 2016 | Publication | Proc. SPIE 9827, Ocean Sensing and Monitoring VIII, 98270B (May 17, 2016) | Abbreviated Journal | Proc. SPIE 9827 |
| Volume | Issue | Pages | |||
| Keywords | Instrumentation; Sensors; Cameras; Long wavelength infrared; Short wave infrared radiation; Spectroscopy; Calibration; Remote sensing; Water; Near infrared; Night vision | ||||
| Abstract | Although advances have been made in oil spill remote detection, many electro-optic sensors do not provide real-time images, do not work well under degraded visual environments, nor provide a measure of extreme oil thickness in marine environments. A joint program now exists between BSEE and NVESD that addresses these capability gaps in remote sensing of oil spills. Laboratory experiments, calibration techniques, and field tests were performed at Fort Belvoir, Virginia; Santa Barbara, California; and the Ohmsett Test Facility in Leonardo, New Jersey. Weathered crude oils were studied spectroscopically and characterized with LWIR, and low-light-level visible/NIR, and SWIR cameras. We designed and fabricated an oil emulsion thickness calibration cell for spectroscopic analysis and ground truth, field measurements. Digital night vision cameras provided real-time, wide-dynamic-range imagery, and were able to detect and recognize oil from full sun to partial moon light. The LWIR camera provided quantitative oil analysis (identification) for >1 mm thick crude oils both day and night. Two filtered, co-registered, SWIR cameras were used to determine whether oil thickness could be measured in real time. Spectroscopic results revealed that oil emulsions vary with location and weathered state and some oils (e.g., ANS and Santa Barbara seeps) do not show the spectral rich features from archived Deep Water Horizon hyperspectral data. Multi-sensor imagery collected during the 2015 USCG Airborne Oil Spill Remote Sensing and Reporting Exercise and the design of a compact, multiband imager are discussed. | ||||
| Address | Active EO Inc. | ||||
| Corporate Author | Thesis | ||||
| Publisher | SPIE | Place of Publication | Editor | ||
| Language | English | Summary Language | English | Original Title | |
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | IDA @ john @ | Serial | 1475 | ||
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| Author | 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. |
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| 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 | Schnitt, S.; Ruhtz, T.; Fischer, J.; Hölker, F.; Kyba, C.C.M. | ||||
| Title | Temperature stability of the sky quality meter | Type |
Journal Article | ||
| Year | 2013 | Publication | Sensors (Basel, Switzerland) | Abbreviated Journal | Sensors (Basel) |
| Volume | 13 | Issue | 9 | Pages | 12166-12174 |
| Keywords | *Artifacts; Atmosphere/*analysis; Environmental Monitoring/*instrumentation; Equipment Design; Equipment Failure Analysis; Photometry/*instrumentation; Reproducibility of Results; Sensitivity and Specificity; Temperature; *Transducers; Sky Quality Meter; SQM | ||||
| Abstract | The stability of radiance measurements taken by the Sky Quality Meter (SQM)was tested under rapidly changing temperature conditions during exposure to a stable light field in the laboratory. The reported radiance was found to be negatively correlated with temperature, but remained within 7% of the initial reported radiance over a temperature range of -15 degrees C to 35 degrees C, and during temperature changes of -33 degrees C/h and +70 degrees C/h.This is smaller than the manufacturer's quoted unit-to-unit systematic uncertainty of 10%,indicating that the temperature compensation of the SQM is adequate under expected outdoor operating conditions. | ||||
| Address | Institute for Space Sciences, Freie Universitat Berlin, Carl-Heinrich-Becker-Weg 6-10, Berlin 12165, Germany. christopher.kyba@wew.fu-berlin.de | ||||
| 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 | 1424-8220 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:24030682; PMCID:PMC3821345 | Approved | no | ||
| Call Number | IDA @ john @ | Serial | 194 | ||
| Permanent link to this record | |||||
| Author | den Outer, P.; Lolkema, D.; Haaima, M.; van der Hoff, R.; Spoelstra, H.; Schmidt, W. | ||||
| Title | Intercomparisons of nine sky brightness detectors | Type |
Journal Article | ||
| Year | 2011 | Publication | Sensors (Basel, Switzerland) | Abbreviated Journal | Sensors (Basel) |
| Volume | 11 | Issue | 10 | Pages | 9603-9612 |
| Keywords | Calibration; Darkness; *Extraterrestrial Environment; Humans; Light; Luminescent Measurements; Netherlands; *Optical Phenomena; Optics and Photonics/*instrumentation/*methods; Sky Quality Meter; artificial lighting; intercalibration; intercomparison; light pollution; night sky brightness | ||||
| Abstract | Nine Sky Quality Meters (SQMs) have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across The Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between +/-14%. Individual night time sums range from -16% to +20%. Intercalibration reduces this to 0.5%, and -7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 +/- 0.003 mcd/m(2) on 12 April, and the largest value was 5.94 +/- 0.03 mcd/m(2) on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent. | ||||
| Address | National Institute for Public Health and the Environment, A. van Leeuwenhoeklaan 9, 3720 BA Bilthoven, The Netherlands. peter.den.outer@rivm.nl | ||||
| 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 | 1424-8220 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:22163715; PMCID:PMC3231263 | Approved | no | ||
| Call Number | IDA @ john @ | Serial | 196 | ||
| Permanent link to this record | |||||