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Author Zhang, K.; Zhong, X.; Zhang, G.; Li, D.; Su, Z.; Meng, Y.; Jiang, Y. url  doi
openurl 
  Title Thermal Stability Optimization of the Luojia 1-01 Nighttime Light Remote-Sensing Camera's Principal Distance Type Journal Article
  Year (down) 2019 Publication Sensors (Basel, Switzerland) Abbreviated Journal Sensors (Basel)  
  Volume 19 Issue 5 Pages  
  Keywords Instrumentation  
  Abstract The instability of the principal distance of the nighttime light remote-sensing camera of the Luojia 1-01 satellite directly affects the geometric accuracy of images, consequently affecting the results of analysis of nighttime light remote-sensing data. Based on the theory of optical passive athermal design, a mathematical model of optical-passive athermal design for principal distance stabilization is established. Positive and negative lenses of different materials and the mechanical structures of different materials are matched to optimize the optical system. According to the index requirements of the Luojia 1-01 camera, an image-telecentric optical system was designed under the guidance of the established mathematical model. In the temperature range of -20 degrees C to +60 degrees C, the principal distance of the system changes from -0.01 mum to +0.28 mum. After on-orbit testing, the geometric accuracy of the designed nighttime light remote-sensing camera is better than 0.20 pixels and less than index requirement of 0.3 pixels, which indicating that the principal distance maintains good stability on-orbit and meets the application requirements of nighttime light remote sensing.  
  Address School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China. jiangyh@whu.edu.cn  
  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:30813556 Approved no  
  Call Number GFZ @ kyba @ Serial 2238  
Permanent link to this record
 

 
Author Cao, X.; Hu, Y.; Zhu, X.; Shi, F.; Zhuo, L.; Chen, J. url  doi
openurl 
  Title A simple self-adjusting model for correcting the blooming effects in DMSP-OLS nighttime light images Type Journal Article
  Year (down) 2019 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment  
  Volume 224 Issue Pages 401-411  
  Keywords Remote Sensing  
  Abstract Night-time light (NTL) data from the Defense Meteorological Satellite Program (DMSP) Operation Linescan System (OLS) provide important observations of human activities; however, DMSP-OLS NTL data suffer from problems such as saturation and blooming. This research developed a self-adjusting model (SEAM) to correct blooming effects in DMSP-OLS NTL data based on a spatial response function and without using any ancillary data. By assuming that the pixels adjacent to the background contain no lights (i.e., pseudo light pixels, PLPs), the blooming effect intensity, a parameter in the SEAM model, can be estimated by pixel-based regression using PLPs and their neighboring light sources. SEAM was applied to all of China, and its performance was assessed for twelve cities with different population sizes. The results show that SEAM can largely reduce the blooming effect in the original DMSP-OLS dataset and enhance its quality. The images after blooming effect correction have higher spatial similarity with Suomi National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (VIIRS) images and higher spatial variability than the original DMSP-OLS data. We also found that the average effective blooming distance is approximately 3.5 km in China, which may be amplified if the city is surrounded by water surfaces, and that the blooming effect intensity is positively correlated to atmospheric quality. The effectiveness of the proposed model will improve the capacity of DMSP-OLS images for mapping the urban extent and modeling socioeconomic parameters.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0034-4257 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2239  
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Author Nagare, R.; Rea, M.S.; Plitnick, B.; Figueiro, M.G. url  doi
openurl 
  Title Effect of White Light Devoid of “Cyan” Spectrum Radiation on Nighttime Melatonin Suppression Over a 1-h Exposure Duration Type Journal Article
  Year (down) 2019 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume in press Issue Pages  
  Keywords Human Health  
  Abstract The intrinsically photosensitive retinal ganglion cells are the main conduit of the light signal emanating from the retina to the biological clock located in the suprachiasmatic nuclei of the hypothalamus. Lighting manufacturers are developing white light sources that are devoid of wavelengths around 480 nm (“cyan gap”) to reduce their impact on the circadian system. The present study was designed to investigate whether exposure to a “cyan-gap,” 3000 K white light source, spectrally tuned to reduce radiant power between 475 and 495 nm (reducing stimulation of the melanopsin-containing photoreceptor), would suppress melatonin less than a conventional 3000 K light source. The study's 2 phases employed a within-subjects experimental design involving the same 16 adult participants. In Phase 1, participants were exposed for 1 h to 3 experimental conditions over the course of 3 consecutive weeks: 1) dim light control (<5 lux at the eyes); 2) 800 lux at the eyes of a 3000 K light source; and 3) 800 lux at the eyes of a 3000 K, “cyan-gap” modified (3000 K mod) light source. The same protocol was repeated in Phase 2, but light levels were reduced to 400 lux at the eyes. As hypothesized, there were significant main effects of light level ( F1,12 = 9.1, p < 0.05, etap(2) = 0.43) and exposure duration ( F1,12 = 47.7, p < 0.05, etap(2) = 0.80) but there was no significant main effect of spectrum ( F1,12 = 0.16, p > 0.05, etap(2) = 0.01). There were no significant interactions with spectrum. Contrary to our model predictions, our results showed that short-term exposures (</= 1 h) to “cyan-gap” light sources suppressed melatonin similarly to conventional light sources of the same CCT and photopic illuminance at the eyes.  
  Address Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0748-7304 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30821188 Approved no  
  Call Number GFZ @ kyba @ Serial 2240  
Permanent link to this record
 

 
Author Marinac, C.R.; Quante, M.; Mariani, S.; Weng, J.; Redline, S.; Cespedes Feliciano, E.M.; Hipp, J.A.; Wang, D.; Kaplan, E.R.; James, P.; Mitchell, J.A. url  doi
openurl 
  Title Associations Between Timing of Meals, Physical Activity, Light Exposure, and Sleep With Body Mass Index in Free-Living Adults Type Journal Article
  Year (down) 2019 Publication Journal of Physical Activity & Health Abbreviated Journal J Phys Act Health  
  Volume 16 Issue 3 Pages 214-221  
  Keywords Human Health  
  Abstract BACKGROUND: This study tested if the timing of meals, physical activity, light exposure, and sleep cluster within individuals and are associated with body mass index (BMI) in a sample of free-living adults (N = 125). METHODS: Data were collected between November 2015 and March 2016 at the University of California, San Diego, Children's Hospital of Philadelphia, and Washington University in St Louis. Height and weight were measured, and BMI (kg/m(2)) was calculated. Sleep timing was estimated using actigraphy, and timing of meals, physical activity, and light exposure were self-reported using a smartphone application. General linear models estimated the mean BMI across time categories of behaviors, adjusting for covariates. A latent class analysis was used to identify patterns of timing variables that clustered within individuals and test for associations between identified patterns and BMI. RESULTS: Later exposure to outdoor light was associated with a lower BMI (P trend < .01). The timing of other behaviors was not independently associated with BMI. The latent class analysis identified 2 distinct groups related to behavioral timing, reflecting an “early bird” and “night owl” phenotype. These phenotypes were not associated with BMI (P > .05). CONCLUSION: Timing of exposures to light, meals, sleep, and physical activity were not strongly associated with BMI in this sample.  
  Address  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1543-3080 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:30798690 Approved no  
  Call Number GFZ @ kyba @ Serial 2241  
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Author Hu, T.; Huang, X. url  doi
openurl 
  Title A novel locally adaptive method for modeling the spatiotemporal dynamics of global electric power consumption based on DMSP-OLS nighttime stable light data Type Journal Article
  Year (down) 2019 Publication Applied Energy Abbreviated Journal Applied Energy  
  Volume 240 Issue Pages 778-792  
  Keywords Remote Sensing  
  Abstract Timely and reliable estimation of electricity power consumption (EPC) is essential to the rational deployment of electricity power resources. Nighttime stable light (NSL) data from the Defense Meteorological Satellite Program Operational Linescan System (DMSP-OLS) have the potential to model global 1-km gridded EPC. A processing chain to estimate EPC includes: (1) NSL data correction; and (2) regression model between EPC statistics and NSL data. For the global gridded EPC estimation, the current approach is to correct the global NSL image in a uniform manner and establish the linear relationships between NSL and EPC. However, the impacts of local socioeconomic inconsistencies on the NSL correction and model establishment are not fully considered. Therefore, in this paper, we propose a novel locally adaptive method for global EPC estimation. Firstly, we set up two options (with or without the correction) for each local area considering the global NSL image is not saturated everywhere. Secondly, three directions (forward, backward, or average) are alternatives for the inter-annual correction to remove the discontinuity effect of NSL data. Thirdly, four optional models (linear, logarithmic, exponential, or second-order polynomial) are adopted for the EPC estimation of each local area with different socioeconomic dynamic. Finally, the options for each step constitute all candidate processing chains, from which the optimal one is adaptively chosen for each local area based on the coefficient of determination. The results demonstrate that our product outperforms the existing one, at global, continental, and national scales. Particularly, the proportion of countries/districts with a high accuracy (MARE (mean of the absolute relative error)  ≤ 10%) increases from 17.8% to 57.8% and the percentage of countries/districts with inaccurate results (MARE > 50%) decreases sharply from 23.0% to 3.7%. This product can enhance the detailed understanding of the spatiotemporal dynamics of global EPC.  
  Address  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0306-2619 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2242  
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