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Author Song, J.; Tong, X.; Wang, L.; Zhao, C.; Prishchepov, A.V.
Title Monitoring finer-scale population density in urban functional zones: A remote sensing data fusion approach Type Journal Article
Year 2019 Publication Landscape and Urban Planning Abbreviated Journal Landscape and Urban Planning
Volume 190 Issue Pages (down) 103580
Keywords Remote Sensing; nighttime light; numerical methods
Abstract Spatial distribution information on population density is essential for understanding urban dynamics. In recent decades, remote sensing techniques have often been applied to assess population density, particularly night-time light data (NTL). However, such attempts have resulted in mapped population density at coarse/medium resolution, which often limits the applicability of such data for fine-scale territorial planning. The improved quality and availability of multi-source remote sensing imagery and location-based service data (LBS) (from mobile networks or social media) offers new potential for providing more accurate population information at the micro-scale level. In this paper, we developed a fine-scale population distribution mapping approach by combining the functional zones (FZ) mapped with high-resolution satellite images, NTL data, and LBS data. Considering the possible variations in the relationship between population distribution and nightlight brightness in functional zones, we tested and found spatial heterogeneity of the relationship between NTL and the population density of LBS samples. Geographically weighted regression (GWR) was thus implemented to test potential improvements to the mapping accuracy. The performance of the following four models was evaluated: only ordinary least squares regression (OLS), only GWR, OLS with functional zones (OLS&FZ) and GWR with functional zones (GWR&FZ). The results showed that NTL-based GWR&FZ was the most accurate and robust approach, with an accuracy of 0.71, while the mapped population density was at a unit of 30 m spatial resolution. The detailed population density maps developed in our approach can contribute to fine-scale urban planning, healthcare and emergency responses in many parts of the world.
Address Department of Geosciences and Natural Resource Management, University of Copenhagen, 1350 Copenhagen, Denmark; songjinchao08(at)163.com
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 0169-2046 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2516
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Author Chen, S.; Li, W.; Yang, S.; Zhang, B.; Li, T.; Du, Y.; Yang, M.; Zhao, H.
Title Evaluation method and reduction measures for the flicker effect in road lighting using fixed Low Mounting Height Luminaires Type Journal Article
Year 2019 Publication Tunnelling and Underground Space Technology Abbreviated Journal Tunnelling and Underground Space Technology
Volume 93 Issue Pages (down) 103101
Keywords Lighting; Vision
Abstract Low Mounting Height Luminaires (LMHL) are used in many cities on viaducts, cross-sea and cross-river bridges due to their unique advantages. However, the flicker effect is an important factor that needs to be considered in road lighting using fixed LMHL. At present, there are not many researchers in the field of international lighting. Previous types of road lighting design were based on the method of the tunnel lighting flicker effect. At the same time, the flicker effect is mainly based on the subjective feelings of people but is not quantified. In this paper, the Flicker Index (FI) is calculated by measuring the parameters of streetlamps to evaluation flicker effect. Secondly, the suggestion to offset the flicker effect in CIE 88-2004 “Guide for the Lighting of Road Tunnels and Underpasses” is to limit the speed of the vehicle and adjust the road light spacing to avoid the flicker sensitive area on human eyes, while ignoring the essential problem of how the flicker effect is generated through the energy level of the stimulating optical signal. Two factors affecting the strength of the flicker effect are proposed: energy ratio and duty cycle. The duty cycle, in time, refers to the proportion of the strong and weak flashing signals during the period; in space, it refers to the proportional relationship between the length of the luminaire and the distance between the lamps, which is related to the running speed of the vehicle. It is consistent with the CIE recommendations for flicker. Thirdly, the essence of the flicker effect is the problem of the energy level of the stimulus signal. This study investigated the reduction in the brightness of the light source, hence reducing the energy of the visual stimulation signal to the human eye in order to judge the degree of fatigue in human vision. The experimental results show that the degree of fatigue in human vision decreases when the brightness of the experimental light source decreases. Therefore, the key to changing the flicker effect of LMHL is to reduce the contrast between the surface brightness of the luminaire and the brightness of the spatial background.
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 0886-7798 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2663
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Author Heger, M.P.; Neumayer, E.
Title The impact of the Indian Ocean tsunami on Aceh's long-term economic growth Type Journal Article
Year 2019 Publication Journal of Development Economics Abbreviated Journal Journal of Development Economics
Volume 141 Issue Pages (down) 102365
Keywords Remote Sensing; Natural disasters; Aceh; Indonesia
Abstract Existing studies typically find that natural disasters have negative economic consequences, resulting in, at best, a recovery to trend after initial losses or, at worst, longer term sustained losses. We exploit the unexpected nature of the 2004 Indian Ocean tsunami for carrying out a quasi-experimental difference-in-differences analysis of flooded districts and sub-districts in Aceh. The Indonesian province saw the single largest aid and reconstruction effort of any developing world region ever afflicted by a natural disaster. We show that this effort triggered higher long-term economic output than would have happened in the absence of the tsunami.
Address The World Bank, Washington D.C., USA
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 0304-3878 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2558
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Author Wang, C.; Chen, Z.; Yang, C.; Li, Q.; Wu, Q.; Wu, J.; Zhang, G.; Yu, B.
Title Analyzing parcel-level relationships between Luojia 1-01 nighttime light intensity and artificial surface features across Shanghai, China: A comparison with NPP-VIIRS data Type Journal Article
Year 2020 Publication International Journal of Applied Earth Observation and Geoinformation Abbreviated Journal International Journal of Applied Earth Observation and Geoinformation
Volume 85 Issue Pages (down) 101989
Keywords Remote Sensing
Abstract Nighttime light (NTL) remote sensing data have been widely used to derive socioeconomic indices at national and regional scales. However, few studies analyzed the factors that may explain NTL variations at a fine scale due to the limited resolution of existing NTL data. As a new generation NTL satellite, Luojia 1-01 provides NTL data with a finer spatial resolution of ∼130 m and can be used to assess the relationship between NTL intensity and artificial surface features on an unprecedented scale. This study represents the first efforts to assess the relationship between Luojia 1-01 NTL intensity and artificial surface features at the parcel level in comparison to the Suomi National Polar-orbiting Partnership-Visible Infrared Imaging Radiometer Suite (NPP-VIIRS) NTL data. Points-of-interest (POIs) and land-use/land-cover (LULC) data were used in random forest (RF) regression models for both Luojia 1-01 and NPP-VIIRS to analyze the feature contribution of artificial surface features to NTL intensity. The results show that luminosity variations in Luojia 1-01 data for different land-use types were more significant than those in NPP-VIIRS data because of the finer spatial resolution and wider measurement range. Seventeen variables extracted from POI and LULC data explained the Luojia 1-01 and NPP-VIIRS NTL intensity, with a good out-of-bag score of 0.62 and 0.76, respectively. Moreover, Luojia 1-01 data had fewer “blooming” phenomena than NPP-VIIRS data, especially for cropland, water body, and rural area. Luojia 1-01 is more suitable for estimating socioeconomic activities and can attain more comprehensive information on human activities, since the feature contribution of POI variables is more sensitive to NTL intensity in the Luojia 1-01 RF regression model than that in the NPP-VIIRS RF regression model.
Address
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Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0303-2434 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2745
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Author Liu, M.; Li, W.; Zhang, B.; Hao, Q.; Xiaowei, G.; Yuchuan, L.
Title Research on the Influence of Weather Conditions on Urban Night Light Environment Type Journal Article
Year 2019 Publication Sustainable Cities and Society Abbreviated Journal Sustainable Cities and Society
Volume 54 Issue Pages (down) 101980
Keywords Skyglow; Weather; sky brightness; Urban
Abstract The increasingly serious urban light pollution has deepened the relevant research, and weather conditions indeed have great impact on the urban night light environment. Based on the SQM instrument, fish-eye camera and weather-related systems, this paper analyzes the changing law of night sky with time and weather. The brightness of the typical clear night sky changes regularly with time, and mainly includes five phases: rapid decline phase, slow decline phase, unstable decline phase, smooth phase, and rapid increase phase of sky brightness. In two phases of the smooth sky brightness, the average sky brightness in the high and low brightness phase respectively is 18.123 mag/arcsecond2 and 18.82 mag/arcsecond2, and about 15 times and 8 times higher than those of the natural night sky. This paper establishes the regression model of typical clear night sky brightness in rapid decline phase and rapid increase phase of sky brightness. The sky magnitude brightness in rainy weather is much lower than that in clear weather, the difference is about 3 mag/arcsecond2, the brightness can be reach 15.63 mag / arcsecond2; the average magnitude brightness in snowy days is about 0.17 mag/arcsecond2 higher than that in cloudy weather. There is a significant correlation among the air quality index, the ground illumination ratio of moon, the atmospheric visibility and the sky brightness. The deepened air pollution can also intensify light pollution, which can increase to 3 and 10 times higher than the night sky brightness under the moderate and severe air pollution. The lunar cycle has the least impact on light pollution in clear days, the sky brightness with the full moon is about 2 and 3 times higher than that without the moon.
Address Corresponding author at: No.2, Ling Gong Road, Gan Jing Zi District, School of Architecture and Fine Art, Dalian University of Technology, Dalian, Liao Ning Province 116024, China; iumingyitj(at)163.com
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 2210-6707 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number GFZ @ kyba @ Serial 2759
Permanent link to this record