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A new damage-adaptive bone remodeling model, in which an algorithm incorporating both strain and damage stimuli, is developed in this paper. Typically, a human proximal femur model is established to predict the bone mass distribution during bone remodeling process. And human physiology damage-repair cycle is considered in the model. The governing equations of the mathematical model, digesting the predecessors' ideas, are numerically solved and implemented into ANSYS software via the user interface of finite element algorithm. With the aid of this novel model, the whole healing behavior of human proximal femur is elucidated properly.

A theoretical model for surface bone remodeling under electromagnetic loads is proposed in this paper. In the model, surface bone remodeling is assumed to be related to growth factors. Growth factors in latent form in osteocytes are released to the bone fluid after the osteocytes are absorbed by osteoclasts, and then regulate the bone formation process. At the same time, environmental loadings can influence the generation of growth factors. This paper shows how surface bone remodeling is triggered under the influence of growth factors. Based on this hypothesis, a computational model is established that simulates the bone coupling remodeling process, including internal and surface bone remodeling. The effects of various loadings, including electrical and magnetic loadings, are simulated and compared. The interactions between internal and surface bone remodeling are investigated via the numerical method. The results indicate that an electromagnetic field can strongly influence the bone remodeling process and that the remodeling process will be altered after surface bone remodeling is triggered, compared to the sole effect of the internal remodeling process.

Buckling and postbuckling behaviors of multi-walled carbon nanotubes (MWCNTs) under a compressive force are studied. MWCNTs are modeled by Donnell's shallow shell nonlinear theory with the allowance of van der Waals (vdW) interaction between the walls. It is shown herein that the buckling load decreases while the buckling strain increases as the innermost radius of MWCNT increases. For the postbuckling behavior, the shortening-load curves show an initial steep gradient that gradually level up when the radius of the innermost tube changes from a small value to a large value. However, the deflection-load curves are almost level for various radii of MWCNTs. In addition, the analytical results showed that the shortening-load curves are almost linear but the deflection-load curves are nonlinear and the stability of MWCNTs can be enhanced by adding tubes.

A direct constraint technique, based on the hybrid-Trefftz finite element method, is first presented to solve elastic contact problems without friction. For efficiency, static condensation is employed to condense a large model down to a smaller one which

Theoretical prediction of surface bone remodeling in the diaphysis of the long bone under various external loads are made within the framework of adaptive elastic theory. These loads include external lateral pressure, electric and thermal loads. Two solutions are presented for analyzing thermoelectroelastic problems of surface bone remodeling. The analytical solution that gives explicit formulation is capable of modeling homogeneous bone materials, while the semi-analytical solution is suitable for analyzing inhomogeneous cases. Numerical results are presented to verify the proposed formulation and to show the effects of mechanical, thermal and electric loads on surface bone remodeling process.