This paper applies the fractal dimension as a characteristic to describe the engine抯 operating condition and its developmental trend. A correlation dimension is one of the quantities that are usually used to characte...This paper applies the fractal dimension as a characteristic to describe the engine抯 operating condition and its developmental trend. A correlation dimension is one of the quantities that are usually used to characterize a strange attractor. With the operation of the phase space reconstruction, respective correlation dimensions of a series of vibration signals obtained under different conditions are calculated to find the intrinsic relationship between the indicator and the operating condition. The experiment result shows that the correlation dimension is sensitive to the condition evolution and convenient for the identification of abnormal operational states. In advanced prognostic algorithm based on the BP neural network is then applied on the correlation dimensions to predict the short-term running conditions in order to avoid severe faults and realize in-time maintenance. Experimental results are presented to illustrate the proposed methodology.展开更多
Non-carbon inorganic fullerene-like (IF) nanoscale materials have recently attracted intense interest due to their nested hollow and nanotube structures. In this letter, IF-WS2 nanoparticles prepared by solid-gas rea...Non-carbon inorganic fullerene-like (IF) nanoscale materials have recently attracted intense interest due to their nested hollow and nanotube structures. In this letter, IF-WS2 nanoparticles prepared by solid-gas reaction were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results show that the IF-WS2 nanoparticles have a nested hollow closed spherical structure with diameter of 100-150 nm.展开更多
The rigid-interface friction model is usually used in the nonlinear vibrationof the rectangular plate with dry friction support edges. The present study provides an extensionby using a hysteretic spring friction model...The rigid-interface friction model is usually used in the nonlinear vibrationof the rectangular plate with dry friction support edges. The present study provides an extensionby using a hysteretic spring friction model and taking account of the stick-slip motion of theplate. Results for a range of problem parameters have been obtained. The results show that thenonlinear frequency response behavior of the system can be quite different from the rigid-interfacefriction model. The effects of the stiffness at friction interfaces and the stick-slip motion on thenonlinear vibration of the plate are significant and hence cannot be neglected.展开更多
文摘This paper applies the fractal dimension as a characteristic to describe the engine抯 operating condition and its developmental trend. A correlation dimension is one of the quantities that are usually used to characterize a strange attractor. With the operation of the phase space reconstruction, respective correlation dimensions of a series of vibration signals obtained under different conditions are calculated to find the intrinsic relationship between the indicator and the operating condition. The experiment result shows that the correlation dimension is sensitive to the condition evolution and convenient for the identification of abnormal operational states. In advanced prognostic algorithm based on the BP neural network is then applied on the correlation dimensions to predict the short-term running conditions in order to avoid severe faults and realize in-time maintenance. Experimental results are presented to illustrate the proposed methodology.
基金This work was supported by the National Natural Science Foundation of China (50171063 20171039 20003009) the Zhejiang Provincial Natural Science Foundation of China (501074,200053) the Israeli Ministry of Science (Tashtiot) and the Israel Scie
文摘Non-carbon inorganic fullerene-like (IF) nanoscale materials have recently attracted intense interest due to their nested hollow and nanotube structures. In this letter, IF-WS2 nanoparticles prepared by solid-gas reaction were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results show that the IF-WS2 nanoparticles have a nested hollow closed spherical structure with diameter of 100-150 nm.
文摘The rigid-interface friction model is usually used in the nonlinear vibrationof the rectangular plate with dry friction support edges. The present study provides an extensionby using a hysteretic spring friction model and taking account of the stick-slip motion of theplate. Results for a range of problem parameters have been obtained. The results show that thenonlinear frequency response behavior of the system can be quite different from the rigid-interfacefriction model. The effects of the stiffness at friction interfaces and the stick-slip motion on thenonlinear vibration of the plate are significant and hence cannot be neglected.
