The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Hua Liao - One of the best experts on this subject based on the ideXlab platform.
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income elasticity of cooking fuel substitution in rural china evidence from Population Census data
Journal of Cleaner Production, 2018Co-Authors: Hua LiaoAbstract:Abstract Solid fuels are still widely used as primary cooking fuel in rural China, which brings severe health, environmental and socio-economic consequences. A sound understanding of the energy transition pattern of rural households will provide valuable insights for policy makers aiming to facilitate transition towards cleaner fuels. The most relevant questions include whether measure of improving income could help facilitate transition and how quickly the transition would happen as household income grows. Using National Population Census data (2000–2010) for over two thousand Chinese counties, we estimated the income elasticities of primary cooking fuel substitution between traditional biomass, coal, gaseous fuels, electric power and others. It is found that the income effect is positive for the cleaner fuels gases and electric power but negative for dirty solid fuels like coal and biomass. However, our estimated elasticities show that the adoption of cleaner fuels (gases and electric power) as primary cooking fuel is income elastic (elasticity>1) for rural village households but income inelastic (elasticity
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energy poverty and solid fuels use in rural china analysis based on national Population Census
Energy for Sustainable Development, 2014Co-Authors: Xin Tang, Hua LiaoAbstract:Abstract There about 490 million rural residents in China use solid fuels for cooking. Based on national Population Census data, this research evaluates the current situation and long-term trend of solid fuel use for cooking in rural China. Firstly, over three-fourths of all rural households depend on solid fuels to meet their cooking demand, while in urban area and township this figure is as low as 8% and 36% respectively. Secondly, solid fuel use was linked closely to rural household income, i.e., those regions with low per capita household income use more solid fuel. Furthermore, the proportion of rural households using solid fuel declined 17 percentage points in 2000-2010, albeit with some significant regional differences. Finally, the proportion of rural residents using clean fuels remained low, and the proportion using gas remained nearly constant over last 10 years in many provinces.
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energy poverty and solid fuels use in rural china analysis based on national Population Census
Research Papers in Economics, 2014Co-Authors: Xin Tang, Hua LiaoAbstract:China has basically achieved ubiquity of electricity access in rural areas during the latest three decades. However, solid fuels are still widely used in the rural areas, which is currently the main issue impinging upon energy poverty in China. There about 490 million rural residents in China using solid fuels for cooking. Based on national Population Census data, this research evaluates the current situation and long-term trend of solid fuel use for cooking in rural China. Firstly, over three-fourths of all rural households depend on solid fuels to meet their cooking demand, whilst in urban area and township this figure is as low as 8 % and 36 % respectively. Secondly, solid fuel use was linked closely to rural household income, i.e., those regions with low per capita household income use more solid fuel. Furthermore, rural households using solid fuel declined by 17 percent from 2000 to 2010, albeit with some significant regional differences. Finally, the proportion of rural residents using clean fuels remained low, and the proportion using gas remained nearly constant over last 10 years in many provinces. Improving access to affordable and reliable energy services for cooking remains a great challenge China need to address.
David M. Bird - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Population Census of a Large Common Tern Colony with a Small Unmanned Aircraft
2016Co-Authors: Dominique Chabot, Shawn R. Craik, David M. BirdAbstract:Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to Census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the fol-lowing day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972–0.989, P< 0.001) and regression coefficients ranged from 0.928–0.977 terns/nest. Full colony aerial counts were 93.6 % and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield Population estimates in the 93–96 % range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird research-ers and managers to consider taking advantage of this burgeoning technology
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Population Census of a large common tern colony with a small unmanned aircraft
PLOS ONE, 2015Co-Authors: Dominique Chabot, Shawn R. Craik, David M. BirdAbstract:Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to Census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972–0.989, P < 0.001) and regression coefficients ranged from 0.928–0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield Population estimates in the 93–96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology.
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Population Census of a large Common tern colony with a small unmanned aircraft
2015Co-Authors: Dominique Chabot, Shawn R. Craik, David M. BirdAbstract:Abstract: Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to Census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972-0.989, P < 0.001) and regression coefficients ranged from 0.928-0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield Population estimates in the 93-96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology. About the data: Raw aerial photos were captured in JPEG format by a Canon Powershot S90 10-megapixel camera mounted on an Aerial Insight AI-Multi electric fixed-wing UAS. The highest quality overlapping photos of each of the two islands comprising the tern colony were then mosaicked using the PTGui panoramic stitching software. Photomosaics were then imported into ArcGIS and georeferenced with ground control points collected with a Trimble Pathfinder GPS at a series of yellow or orange plastic cones (visible in the imagery) marking the centre of plots in which ground nest counts were compared to aerial tern counts. Overall disturbance levels on each of the two islands were scored on a scale of 0–2 from a distance by an observer at 30-second intervals throughout UAS flights as well as "matched" control periods starting 10 minutes following landing. For more information about this research or the data, please contact: dominique.chabot@mail.mcgill.ca
Dominique Chabot - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Population Census of a Large Common Tern Colony with a Small Unmanned Aircraft
2016Co-Authors: Dominique Chabot, Shawn R. Craik, David M. BirdAbstract:Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to Census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the fol-lowing day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972–0.989, P< 0.001) and regression coefficients ranged from 0.928–0.977 terns/nest. Full colony aerial counts were 93.6 % and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield Population estimates in the 93–96 % range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird research-ers and managers to consider taking advantage of this burgeoning technology
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Population Census of a large common tern colony with a small unmanned aircraft
PLOS ONE, 2015Co-Authors: Dominique Chabot, Shawn R. Craik, David M. BirdAbstract:Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to Census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972–0.989, P < 0.001) and regression coefficients ranged from 0.928–0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield Population estimates in the 93–96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology.
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Population Census of a large Common tern colony with a small unmanned aircraft
2015Co-Authors: Dominique Chabot, Shawn R. Craik, David M. BirdAbstract:Abstract: Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to Census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R2 = 0.972-0.989, P < 0.001) and regression coefficients ranged from 0.928-0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield Population estimates in the 93-96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology. About the data: Raw aerial photos were captured in JPEG format by a Canon Powershot S90 10-megapixel camera mounted on an Aerial Insight AI-Multi electric fixed-wing UAS. The highest quality overlapping photos of each of the two islands comprising the tern colony were then mosaicked using the PTGui panoramic stitching software. Photomosaics were then imported into ArcGIS and georeferenced with ground control points collected with a Trimble Pathfinder GPS at a series of yellow or orange plastic cones (visible in the imagery) marking the centre of plots in which ground nest counts were compared to aerial tern counts. Overall disturbance levels on each of the two islands were scored on a scale of 0–2 from a distance by an observer at 30-second intervals throughout UAS flights as well as "matched" control periods starting 10 minutes following landing. For more information about this research or the data, please contact: dominique.chabot@mail.mcgill.ca
Yoshiki Yamagata - One of the best experts on this subject based on the ideXlab platform.
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analysis of urban growth and estimating Population density using satellite images of nighttime lights and land use and Population data
Giscience & Remote Sensing, 2015Co-Authors: Hasi Bagan, Yoshiki YamagataAbstract:We investigated the spatiotemporal dynamics of urban expansion in Japan from 1990 to 2006 by using gridded land-use data, Population Census data, and satellite images of nighttime lights. First, we mapped Defense Meteorological Satellite Program (DMSP) nighttime lights and land-use data onto the 1 km2 grid cell system of Japan to determine the proportional areas of DMSP and urban land use within each grid cell. Then, we investigated the relationships among Population density, DMSP, and urban area. The urban/built-up area was strongly positively correlated with Population density, and rapid expansion of the urban/built-up area around megacities was associated with Population increases. In contrast, Population density dropped steeply in rural areas and in small towns. Statistical analysis showed that correlation coefficients between Population density and DMSP increased as the DMSP nighttime lights brightness value increased. We next estimated Population density in the Hokkaido region using an ordinary leas...
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landsat analysis of urban growth how tokyo became the world s largest megacity during the last 40 years
Remote Sensing of Environment, 2012Co-Authors: Héctor Bagán, Yoshiki YamagataAbstract:Abstract Combining remote sensing data and socio-economic data to quantitatively analyze urban growth is a topic growing in importance. We used square grid cells to investigate the spatial and temporal dynamics of urban growth in the Tokyo, Japan, metropolitan area by using remote sensing imagery from 1972 to 2011 and Census Population data from 1970 to 2010. First, we used the subspace classification method to produce land-cover maps by using Landsat images from 1972, 1987, 2001, and 2011. Next, we integrated the land-cover maps with basic grid cell maps (using the standard 1 km2 grid cell system of Japan) to represent the proportion of each land-cover category within each 1 km2 grid cell area. Finally, we combined the proportional land-cover maps and Population Census data to investigate the relationship between land-cover changes and Population density change based on grid cells. By using grid cells it is straightforward to (i) integrate remote sensing, geographic information system (GIS), and statistical data within the cells; (ii) quantify land-cover changes in terms of the percentage of area affected and rates of change and compare them with Population Census data; and (iii) analyze the spatial-temporal dynamics of urban growth patterns. Between 1972 and 2011 the rapid expansion of the urban area was accompanied by extensive shrinking of the agricultural area around the new settlements. As a result, the urban growth rate exceeded the Population growth rate by more than a factor of 2.6. We used the grid cells to investigate the spatial relationship between the changes of land-cover classes and Population density change, and then calculated the correlation coefficients of land-cover categories and Population density changes for 3 intervals between 1972 and 2011 (1972–1987, 1987–2001, and 2001–2011). The results showed that the urban/built-up density decreased in the metropolitan inner core as the city center experienced dePopulation. Spatial correlation analysis showed a strong positive correlation between urban expansion and Population density change (r = 0.59), and that urban expansion was strongly negatively correlated with cropland change (r = − 0.77). The results also demonstrated that grid cells allow remote sensing and statistics data to be combined, improving the knowledge, understanding, and analysis of urban dynamics.
Maitiniyazi Maimaitijiang - One of the best experts on this subject based on the ideXlab platform.
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drivers of land cover and land use changes in st louis metropolitan area over the past 40 years characterized by remote sensing and Census Population data
International Journal of Applied Earth Observation and Geoinformation, 2015Co-Authors: Maitiniyazi Maimaitijiang, Abduwasit Ghulam, J Onesimo S Sandoval, Matthew MaimaitiyimingAbstract:Abstract In this study, we explored the spatial and temporal patterns of land cover and land use (LCLU) and Population change dynamics in the St. Louis Metropolitan Statistical Area. The goal of this paper was to quantify the drivers of LCLU using long-term Landsat data from 1972 to 2010. First, we produced LCLU maps by using Landsat images from 1972, 1982, 1990, 2000, and 2010. Next, tract level Population data of 1970, 1980, 1990, 2000, and 2010 were converted to 1-km square grid cells. Then, the LCLU maps were integrated with basic grid cell data to represent the proportion of each land cover category within a grid cell area. Finally, the proportional land cover maps and Population Census data were combined to investigate the relationship between land cover and Population change based on grid cells using Pearson's correlation coefficient, ordinary least square (OLS), and local level geographically weighted regression (GWR). Land cover changes in terms of the percentage of area affected and rates of change were compared with Population Census data with a focus on the analysis of the spatial-temporal dynamics of urban growth patterns. The correlation coefficients of land cover categories and Population changes were calculated for two decadal intervals between 1970 and 2010. Our results showed a causal relationship between LCLU changes and Population dynamics over the last 40 years. Urban sprawl was positively correlated with Population change. However, the relationship was not linear over space and time. Spatial heterogeneity and variations in the relationship demonstrate that urban sprawl was positively correlated with Population changes in suburban area and negatively correlated in urban core and inner suburban area of the St. Louis Metropolitan Statistical Area. These results suggest that the imagery reflects processes of urban growth, inner-city decline, Population migration, and social spatial inequality. The implications provide guidance for sustainable urban planning and development. We also demonstrate that grid cells allow robust synthesis of remote sensing and socioeconomic data to advance our knowledge of urban growth dynamics from both spatial and temporal scales and its association with Population change.