During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the s...During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.展开更多
A nonlinear saturation mechanism for reversed shear Alfvén eigenmode(RSAE)is proposed and analyzed,and is shown to be of relevance to typical reactor parameter region.The saturation is achieved through the genera...A nonlinear saturation mechanism for reversed shear Alfvén eigenmode(RSAE)is proposed and analyzed,and is shown to be of relevance to typical reactor parameter region.The saturation is achieved through the generation of high-frequency quasi-mode due to nonlinear coupling of two RSAEs,which is then damped due to coupling with the shear Alfvén continuum,and leads to the nonlinear saturation of the primary RSAEs.An estimation of the nonlinear damping rate is also provided.展开更多
This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic mo...This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering.展开更多
Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain.The five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,...Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain.The five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,respectively.The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and discussed.The results show that the yield stress of the lithosphere has profound effects on the tectonic convective modes.With the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes.Additionally,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes increases.Specifically,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic modes.Furthermore,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate increases.The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental petrography.If the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective mode.The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution.If the lithospheric strength was only 150 MPa,plate tectonics in the early mantle rapid cooling model would have begun before 3.8 Ga,and plate tectonics in the late mantle rapid cooling model would have begun at approximately 1.5 Ga.However,at a lithospheric strength of 200 MPa,plate tectonics in the late mantle rapid cooling model would have begun later than 0.95 Ga,and plate tectonics in the early mantle rapid cooling model would have begun at approximately 2 Ga.The early Earth was in the episodic stagnant-lid convective mode,which means that subduction might still have occurred at that time.The presence of the episodic plate-like mobile-lid convective mode in Earth's later history indicates that there might also have been intermittent surface stagnation during plate tectonics,which may provide an explanation for the quiet period of tectonic activity at approximately 1.0 Ga on Earth.This indicates that tectonic inactivity during a geological period is not an indicator that plate tectonics did not begin.展开更多
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.展开更多
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine. NRR publishes original contributions written by experts and leaders in the fields of neuroanatomy, pathology, physiology, biochemistry, pharmacology, immunology, and auxanology approaches to examine neural regeneration research;展开更多
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.展开更多
The latest research achievements will be presented in each periodical, including articles concerning cerebral structure and function, spinal structure and function, and peripheral nerve structure and function.
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineeringand neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.展开更多
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve ceils and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve ceils and tissue elements during development and disease. The joumal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.展开更多
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and展开更多
The latest research achievements will be presented in each periodical, including articles concerning cerebral structure and function, spinal structure and function, and peripheral nerve structure and function.
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysioiogical changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.展开更多
In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements duri...In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.展开更多
The latest research achievements will be presented in each periodical, including articles conceming cerebral structure and function, spinal structure and function, and peripheral nerve structure and function.
基金supported by the National Natural Science Foundation of China [grant number 42088101]。
文摘During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB0790000)the Collaborative Innovation Program of Hefei Science Center,CAS(No.2022HSC-CIP008)National Natural Science Foundation of China(Nos.12275236 and 12261131622)。
文摘A nonlinear saturation mechanism for reversed shear Alfvén eigenmode(RSAE)is proposed and analyzed,and is shown to be of relevance to typical reactor parameter region.The saturation is achieved through the generation of high-frequency quasi-mode due to nonlinear coupling of two RSAEs,which is then damped due to coupling with the shear Alfvén continuum,and leads to the nonlinear saturation of the primary RSAEs.An estimation of the nonlinear damping rate is also provided.
基金supported by the National Natural Science Foundation of China(Nos.62103052 and No.52175214)。
文摘This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering.
基金supported by the National Natural Science Foundation of China(Grant Nos.42074105 and 92155204)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB 41000000)。
文摘Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain.The five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,respectively.The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and discussed.The results show that the yield stress of the lithosphere has profound effects on the tectonic convective modes.With the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes.Additionally,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes increases.Specifically,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic modes.Furthermore,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate increases.The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental petrography.If the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective mode.The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution.If the lithospheric strength was only 150 MPa,plate tectonics in the early mantle rapid cooling model would have begun before 3.8 Ga,and plate tectonics in the late mantle rapid cooling model would have begun at approximately 1.5 Ga.However,at a lithospheric strength of 200 MPa,plate tectonics in the late mantle rapid cooling model would have begun later than 0.95 Ga,and plate tectonics in the early mantle rapid cooling model would have begun at approximately 2 Ga.The early Earth was in the episodic stagnant-lid convective mode,which means that subduction might still have occurred at that time.The presence of the episodic plate-like mobile-lid convective mode in Earth's later history indicates that there might also have been intermittent surface stagnation during plate tectonics,which may provide an explanation for the quiet period of tectonic activity at approximately 1.0 Ga on Earth.This indicates that tectonic inactivity during a geological period is not an indicator that plate tectonics did not begin.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine. NRR publishes original contributions written by experts and leaders in the fields of neuroanatomy, pathology, physiology, biochemistry, pharmacology, immunology, and auxanology approaches to examine neural regeneration research;
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.
文摘The latest research achievements will be presented in each periodical, including articles concerning cerebral structure and function, spinal structure and function, and peripheral nerve structure and function.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineeringand neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve ceils and tissue elements during development and disease. The joumal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and
文摘The latest research achievements will be presented in each periodical, including articles concerning cerebral structure and function, spinal structure and function, and peripheral nerve structure and function.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysioiogical changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.
文摘In 2009, NRR will emphasis on novel findings in the mechanism research of nerve cells and tissue regeneration, involved in structure change, interactions and specific properties of nerve cells and tissue elements during development and disease. The journal has focused on research concerning the histomorphological changes of nerve cells, neural tissue engineering and neurodegeneration, and also the pathophysiological changes during nerve cells and tissue regeneration with treatment of traditional Chinese medicine.
文摘The latest research achievements will be presented in each periodical, including articles conceming cerebral structure and function, spinal structure and function, and peripheral nerve structure and function.
