The highly dynamic nature of agro-ecosystems in space and time usually leads to high intra-class variance and low inter-class separability in the fine spatial resolution(FSR)remotely sensed imagery.This makes traditio...The highly dynamic nature of agro-ecosystems in space and time usually leads to high intra-class variance and low inter-class separability in the fine spatial resolution(FSR)remotely sensed imagery.This makes traditional classifiers essentially relying on spectral information for crop mapping from FSR imagery an extremely challenging task.To mine effectively the rich spectral and spatial information in FSR imagery,this paper proposed a Scale Sequence Object-based Convolutional Neural Network(SS-OCNN)that classifies images at the object level by taking segmented objects(crop parcels)as basic units of analysis,thus,ensuring that the boundaries between crop parcels are delineated precisely.These segmented objects were subsequently classified using a CNN model integrated with an automatically generated scale sequence of input patch sizes.This scale sequence can fuse effectively the features learned at different scales by transforming progressively the information extracted at small scales to larger scales.The effectiveness of the SS-OCNN was investigated using two heterogeneous agricultural areas with FSR SAR and optical imagery,respectively.Experimental results revealed that the SS-OCNN consistently achieved the most accurate classification results.The SS-OCNN,thus,provides a new paradigm for crop classification over heterogeneous areas using FSR imagery,and has a wide application prospect.展开更多
This review outlines the benefits of using multiple approaches to improve model design and facilitate multidisciplinary research into infectious diseases,as well as showing and proposing practical examples of effectiv...This review outlines the benefits of using multiple approaches to improve model design and facilitate multidisciplinary research into infectious diseases,as well as showing and proposing practical examples of effective integration.It looks particularly at the benefits of using participatory research in conjunction with traditional modelling methods to potentially improve disease research,control and management.Integrated approaches can lead to more realistic mathematical models which in turn can assist with making policy decisions that reduce disease and benefit local people.The emergence,risk,spread and control of diseases are affected by many complex bio-physical,environmental and socio-economic factors.These include climate and environmental change,land-use variation,changes in population and people’s behaviour.The evidence base for this scoping review comes from the work of a consortium,with the aim of integrating modelling approaches traditionally used in epidemiological,ecological and development research.A total of five examples of the impacts of participatory research on the choice of model structure are presented.Example 1 focused on using participatory research as a tool to structure a model.Example 2 looks at identifying the most relevant parameters of the system.Example 3 concentrates on identifying the most relevant regime of the system(e.g.,temporal stability or otherwise),Example 4 examines the feedbacks from mathematical models to guide participatory research and Example 5 goes beyond the so-far described two-way interplay between participatory and mathematical approaches to look at the integration of multiple methods and frameworks.This scoping review describes examples of best practice in the use of participatory methods,illustrating their potential to overcome disciplinary hurdles and promote multidisciplinary collaboration,with the aim of making models and their predictions more useful for decision-making and policy formulation.展开更多
Soil moisture,a crucial property for Earth surface research,has been focused widely in various studies.The Soil Moisture Active Passive(SMAP)global products at 36 km and 9 km(called P36 and AP9 in this research)have b...Soil moisture,a crucial property for Earth surface research,has been focused widely in various studies.The Soil Moisture Active Passive(SMAP)global products at 36 km and 9 km(called P36 and AP9 in this research)have been published from April 2015.However,the 9 km AP9 product was retrieved from the active radar and L-band passive radiometer and the active radar failed in July 2015.In this research,the virtual image pair-based spatiotemporal fusion model was coupled with a spatial weighting scheme(VIPSTF-SW)to simulate the 9 km AP9 data after failure of the active radar.The method makes full use of all the historical AP9 and P36 data available between April and July 2015.As a result,8-day composited 9 km SMAP data at the global scale were produced from 2015 to 2020,by downscaling the corresponding 8-day composited P36 data.The available AP9 data and in situ reference data were used to validate the predicted 9 km data.Generally,the predicted 9 km SMAP data can provide more spatial details than P36 and are more accurate than the existing EP9 product.The VIPSTF-SW-predicted 9 km SMAP data are an accurate substitute for AP9 and will be made freely available to support research and applications in hydrology,climatology,ecology,and many other fields at the global scale.展开更多
基金supported by the National Natural Science Foundation of China(41301465)the Capital Construction Fund of Jilin Province(2021C045-2)the Open Fund of State Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University(grant number 20R04).
文摘The highly dynamic nature of agro-ecosystems in space and time usually leads to high intra-class variance and low inter-class separability in the fine spatial resolution(FSR)remotely sensed imagery.This makes traditional classifiers essentially relying on spectral information for crop mapping from FSR imagery an extremely challenging task.To mine effectively the rich spectral and spatial information in FSR imagery,this paper proposed a Scale Sequence Object-based Convolutional Neural Network(SS-OCNN)that classifies images at the object level by taking segmented objects(crop parcels)as basic units of analysis,thus,ensuring that the boundaries between crop parcels are delineated precisely.These segmented objects were subsequently classified using a CNN model integrated with an automatically generated scale sequence of input patch sizes.This scale sequence can fuse effectively the features learned at different scales by transforming progressively the information extracted at small scales to larger scales.The effectiveness of the SS-OCNN was investigated using two heterogeneous agricultural areas with FSR SAR and optical imagery,respectively.Experimental results revealed that the SS-OCNN consistently achieved the most accurate classification results.The SS-OCNN,thus,provides a new paradigm for crop classification over heterogeneous areas using FSR imagery,and has a wide application prospect.
基金Dynamic Drivers of Disease in Africa Consortium,NERC project no.NE-J001570-1was funded with support from the Ecosystem Services for Poverty Alleviation(ESPA)programme+1 种基金The ESPA programme is funded by the Department for International Development(DFID)the Economic and Social Research Council(ESRC)and the Natural Environment Research Council(NERC).
文摘This review outlines the benefits of using multiple approaches to improve model design and facilitate multidisciplinary research into infectious diseases,as well as showing and proposing practical examples of effective integration.It looks particularly at the benefits of using participatory research in conjunction with traditional modelling methods to potentially improve disease research,control and management.Integrated approaches can lead to more realistic mathematical models which in turn can assist with making policy decisions that reduce disease and benefit local people.The emergence,risk,spread and control of diseases are affected by many complex bio-physical,environmental and socio-economic factors.These include climate and environmental change,land-use variation,changes in population and people’s behaviour.The evidence base for this scoping review comes from the work of a consortium,with the aim of integrating modelling approaches traditionally used in epidemiological,ecological and development research.A total of five examples of the impacts of participatory research on the choice of model structure are presented.Example 1 focused on using participatory research as a tool to structure a model.Example 2 looks at identifying the most relevant parameters of the system.Example 3 concentrates on identifying the most relevant regime of the system(e.g.,temporal stability or otherwise),Example 4 examines the feedbacks from mathematical models to guide participatory research and Example 5 goes beyond the so-far described two-way interplay between participatory and mathematical approaches to look at the integration of multiple methods and frameworks.This scoping review describes examples of best practice in the use of participatory methods,illustrating their potential to overcome disciplinary hurdles and promote multidisciplinary collaboration,with the aim of making models and their predictions more useful for decision-making and policy formulation.
基金This research was supported by the National Natural Science Foundation of China under Grants 42171345 and 41971297Tongji University under Grant 02502350047.
文摘Soil moisture,a crucial property for Earth surface research,has been focused widely in various studies.The Soil Moisture Active Passive(SMAP)global products at 36 km and 9 km(called P36 and AP9 in this research)have been published from April 2015.However,the 9 km AP9 product was retrieved from the active radar and L-band passive radiometer and the active radar failed in July 2015.In this research,the virtual image pair-based spatiotemporal fusion model was coupled with a spatial weighting scheme(VIPSTF-SW)to simulate the 9 km AP9 data after failure of the active radar.The method makes full use of all the historical AP9 and P36 data available between April and July 2015.As a result,8-day composited 9 km SMAP data at the global scale were produced from 2015 to 2020,by downscaling the corresponding 8-day composited P36 data.The available AP9 data and in situ reference data were used to validate the predicted 9 km data.Generally,the predicted 9 km SMAP data can provide more spatial details than P36 and are more accurate than the existing EP9 product.The VIPSTF-SW-predicted 9 km SMAP data are an accurate substitute for AP9 and will be made freely available to support research and applications in hydrology,climatology,ecology,and many other fields at the global scale.