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This paper presents a novel crack size estimation method based on dilated convolution and time series fine tuning using in‐situ Lamb wave. The contributions of this proposed method are twofold: (1) a dilated convolution‐based neural network which is an effective representation learning methods with larger receptive fields for periodic signals and (2) a crack length adjustment approach based on previous estimations with a time series fine tuning method. The time series fine tuning method utilizes the monotonicity of the crack length with respect to time. A new evaluation metric has been adopted, which considers prediction errors, time errors, and monotonicity errors. The proposed method outperforms the previous feature extraction‐based methods with or without time series fine tuning in this new evaluation metric. Highlights: Crack estimation method using deep learning and time series fine tuning was proposed.The neural network using a combination of dilated convolution and long short‐term memory (LSTM) network was designed.The proposed method outperformed prior manual feature extraction‐based approaches. [ABSTRACT FROM AUTHOR]

A study of the micromechanical behavior to predict the overall response of short fiber-reinforced composites under cyclic mechanical and thermal loading is presented. The instantaneous average over a “representative volume” of the material is considered. The influence of the short fiber’s aspect ratio, volume fraction, and spatial orientation has been investigated. The linear combined hardening model is used to describe the cyclic hardening effects in the case of metal matrix. A numerical procedure is used to predict the response of composites under mechanical and thermal conditions. The results of the numerical procedure have been compared to the results of three different models and to published experimental data.

Abstract: The dynamic compressive properties of SiC particle reinforced pure Al matrix composites, fabricated by spark plasma sintering technique with mixture powders prepared by mechanical alloying process, were tested in this paper. Two different average SiC particle sizes of 12μm and 45μm were adopted, and the compressive tests of these composites at strain rates ranging from 800/s to 5200/s were conducted by split Hopkinson pressure bar. The damage mechanism of the SiCp/Al composites was analyzed through the microstructural observations and high-precision density measurements. Results show that the dynamic properties and damage accumulation of these composites are significantly affected by the particle distribution, size, particle cracking, particle/matrix interface debonding and adiabatic heat softening. The composites containing smaller SiC particles exhibit higher flow stress, lower strain rate sensitivity, and less damage at high strain rate deformation. [Copyright &y& Elsevier]

A theoretical model is developed to describe the influence of external loads on the equilibrium shapes of adhering tubular lipid vesicles. In the case of nonspecific adhesion, the equilibrium shape equations and boundary conditions are derived through the method analogous to previous research. For a range of applied forces, locally stable bound shapes are simulated. Along with the increase or decrease the external force, the process for adhering vesicle disengaging from or sprawling to the substrate is predicted and analyzed. [ABSTRACT FROM AUTHOR]

Equilibrium shapes of vesicles composed of a mixture of partially miscible amphiphiles are investigated. To take into account the influences of the composition, a simple phenomenological coupling between the co mposition and the curvatures, including the mean curvature and the Gauss curvature of the membrane surface, is suggested. By minimizing the potential functional, the general shape equation is obtained and solved analytically for vesicles with simple shapes. Besides, the geometrical constraint equation and geometrically permissible condition for the two-component lipid vesicles are put forward. The influences of physical parameters on the geometrically permissible phase diagrams are predicted. The close relations between the predictions and existing experimental phenomena published recently are shown. [ABSTRACT FROM AUTHOR]