The effects of the supported angle on the stability and dynamical bifurcations of an inclined cantilevered pipe conveying fluid are investigated. First, a theoretical model of the pipe is developed through the force b...The effects of the supported angle on the stability and dynamical bifurcations of an inclined cantilevered pipe conveying fluid are investigated. First, a theoretical model of the pipe is developed through the force balance and stress-strain relationship. Second, the response surfaces, stability, and critical lines of the typical hanging system (H-S) and standing system (S-S) are discussed based on the modal analysis. Last, the bifurcation diagrams of the pipe are presented for different supported angles. It is shown that pipes will undergo a series of bifurcation processes and show rich dynamic phenomena such as buckling, Hopf bifurcation, period-doubling bifurcation, chaotic motion, and divergence motion.展开更多
Multi-sensor measurement iswidely employed in rotatingmachinery to ensure the safety ofmachines.The information provided by the single sensor is not comprehensive.Multi-sensor signals can provide complementary informa...Multi-sensor measurement iswidely employed in rotatingmachinery to ensure the safety ofmachines.The information provided by the single sensor is not comprehensive.Multi-sensor signals can provide complementary information in characterizing the health condition of machines.This paper proposed a multi-sensor fusion convolution neural network(MF-CNN)model.The proposed model adds a 2-D convolution layer before the classical 1-D CNN to automatically extract complementary features of multi-sensor signals and minimize the loss of information.A series of experiments are carried out on a rolling bearing test rig to verify the model.Vibration and sound signals are fused to achieve higher classification accuracy than typical machine learning model.In addition,the model is further applied to gas turbine abnormal detection,and shows great robustness and generalization.展开更多
Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological applications.The bond-cleavage t...Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological applications.The bond-cleavage type and position of biomolecular remain a great challenge,which determines the metabolic pathway of the targets in living systems.Herein we designed two linkages of methylene and carbonyl group attached the N-3 position of the 5-ethynyl-2’-deoxyuridine(EdU)base or the oxygen atom at deoxyribose 3’position to a photocaging group,which would be cleaved by irradiation with 365 nm ultraviolet light.EdU derivatives linked by methylene at the N-3 position had better photodecage efficiency and stability in the absence of light.This paper provides a strategy for studying the nucleoside metabolic pathways in cells,which can easily and conveniently evaluate the effect of the position and type of the linkages.The developed strategy affords a reference for controlling spatial and temporal metabolism of small-molecule drugs,allowing direct manipulation of intact cells under physiological conditions.展开更多
基金Project supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.51221004)the National Natural Science Foundation of China(Nos.11172260,11072213,and 51375434)the Higher School Specialized Research Fund for the Doctoral Program(No.20110101110016)
文摘The effects of the supported angle on the stability and dynamical bifurcations of an inclined cantilevered pipe conveying fluid are investigated. First, a theoretical model of the pipe is developed through the force balance and stress-strain relationship. Second, the response surfaces, stability, and critical lines of the typical hanging system (H-S) and standing system (S-S) are discussed based on the modal analysis. Last, the bifurcation diagrams of the pipe are presented for different supported angles. It is shown that pipes will undergo a series of bifurcation processes and show rich dynamic phenomena such as buckling, Hopf bifurcation, period-doubling bifurcation, chaotic motion, and divergence motion.
基金support from the National Natural Science Foundation of China (Grant No.U1809219)the Key Research and Development Project of Zhejiang Province (Grant No.2020C01088).
文摘Multi-sensor measurement iswidely employed in rotatingmachinery to ensure the safety ofmachines.The information provided by the single sensor is not comprehensive.Multi-sensor signals can provide complementary information in characterizing the health condition of machines.This paper proposed a multi-sensor fusion convolution neural network(MF-CNN)model.The proposed model adds a 2-D convolution layer before the classical 1-D CNN to automatically extract complementary features of multi-sensor signals and minimize the loss of information.A series of experiments are carried out on a rolling bearing test rig to verify the model.Vibration and sound signals are fused to achieve higher classification accuracy than typical machine learning model.In addition,the model is further applied to gas turbine abnormal detection,and shows great robustness and generalization.
基金supported by the National Natural Science Foundation of China(Nos.21432008,91753201 and 21721005)the large-scale instrument and equipment sharing foundation of Wuhan University。
文摘Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological applications.The bond-cleavage type and position of biomolecular remain a great challenge,which determines the metabolic pathway of the targets in living systems.Herein we designed two linkages of methylene and carbonyl group attached the N-3 position of the 5-ethynyl-2’-deoxyuridine(EdU)base or the oxygen atom at deoxyribose 3’position to a photocaging group,which would be cleaved by irradiation with 365 nm ultraviolet light.EdU derivatives linked by methylene at the N-3 position had better photodecage efficiency and stability in the absence of light.This paper provides a strategy for studying the nucleoside metabolic pathways in cells,which can easily and conveniently evaluate the effect of the position and type of the linkages.The developed strategy affords a reference for controlling spatial and temporal metabolism of small-molecule drugs,allowing direct manipulation of intact cells under physiological conditions.