In this paper, the problem of time-varying aerodynamic parameters identification under measurement noises is studied. By analyzing the key aerodynamic parameters that affect the aircraft control system, a system model...In this paper, the problem of time-varying aerodynamic parameters identification under measurement noises is studied. By analyzing the key aerodynamic parameters that affect the aircraft control system, a system model with extended states for identifying equivalent aerodynamic parameters is established, and error parameters are extended to the system state, avoiding the difficulty caused by the unknown dynamic in the system. Furthermore, an identification algorithm based on extended state Kalman filter is designed, and it is proved that the algorithm has quasi-consistency, thus, the estimation error can be evaluated in real time. Finally, the simulation results under typical flight scenarios show that the designed algorithm can accurately identify aerodynamic parameters, and has desired convergence speed and convergence precision.展开更多
Recent pandemic outbreak of the corona-virus disease 2019(COVID-19)has raised widespread concerns about the importance of the bioaerosols.They are atmospheric aerosol particles of biological origins,mainly including b...Recent pandemic outbreak of the corona-virus disease 2019(COVID-19)has raised widespread concerns about the importance of the bioaerosols.They are atmospheric aerosol particles of biological origins,mainly including bacteria,fungi,viruses,pollen,and cell debris.Bioaerosols can exert a substantial impact on ecosystems,climate change,air quality,and public health.Here,we review several relevant topics on bioaerosols,including sampling and detection techniques,characterization,effects on health and air quality,and control methods.However,very few studies have focused on the source apportionment and transport of bioaerosols.The knowledge of the sources and transport pathways of bioaerosols is essential for a comprehensive understanding of the role microorganisms play in the atmosphere and control the spread of epidemic diseases associated with them.Therefore,this review comprehensively summarizes the up to date progress on the source characteristics,source identification,and diffusion and transport process of bioaerosols.We intercompare three types of diffusion and transport models,with a special emphasis on a widely used mathematical model.This review also highlights the main factors affecting the source emission and transport process,such as biogeographic regions,land-use types,and environmental factors.Finally,this review outlines future perspectives on bioaerosols.展开更多
基金supported by the National Natural Science Foundation of China(No.62122083)Youth Innovation Promotion Association,CAS.
文摘In this paper, the problem of time-varying aerodynamic parameters identification under measurement noises is studied. By analyzing the key aerodynamic parameters that affect the aircraft control system, a system model with extended states for identifying equivalent aerodynamic parameters is established, and error parameters are extended to the system state, avoiding the difficulty caused by the unknown dynamic in the system. Furthermore, an identification algorithm based on extended state Kalman filter is designed, and it is proved that the algorithm has quasi-consistency, thus, the estimation error can be evaluated in real time. Finally, the simulation results under typical flight scenarios show that the designed algorithm can accurately identify aerodynamic parameters, and has desired convergence speed and convergence precision.
基金the National Natural Science Foundation of China(Grant No.51478045)the Fund Project of Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control(GKECHRC-07)+1 种基金the Fund Project of Shaanxi Key Laboratory of Land Consolidation(2018-ZD04)the Opening Fund of State Key Laboratory of Green Building in Western China(LSKF202008).
文摘Recent pandemic outbreak of the corona-virus disease 2019(COVID-19)has raised widespread concerns about the importance of the bioaerosols.They are atmospheric aerosol particles of biological origins,mainly including bacteria,fungi,viruses,pollen,and cell debris.Bioaerosols can exert a substantial impact on ecosystems,climate change,air quality,and public health.Here,we review several relevant topics on bioaerosols,including sampling and detection techniques,characterization,effects on health and air quality,and control methods.However,very few studies have focused on the source apportionment and transport of bioaerosols.The knowledge of the sources and transport pathways of bioaerosols is essential for a comprehensive understanding of the role microorganisms play in the atmosphere and control the spread of epidemic diseases associated with them.Therefore,this review comprehensively summarizes the up to date progress on the source characteristics,source identification,and diffusion and transport process of bioaerosols.We intercompare three types of diffusion and transport models,with a special emphasis on a widely used mathematical model.This review also highlights the main factors affecting the source emission and transport process,such as biogeographic regions,land-use types,and environmental factors.Finally,this review outlines future perspectives on bioaerosols.