OBJECTIVES Arterial tortuosity is a frequent manifestation of vascular disease and collateral vessel growth, but its causes are poorly understood. This study was designed to assess the relationship between the development of tortuosity and the mechanical forces that are imposed on arterial tissue. METHODS AND RESULTS Axial strain in rabbit carotid arteries was reduced from 62+/-2% to 33+/-2% ...

A practical data recovery method is proposed for the strain data lost during the safety monitoring of mega columns. The analytical relations among the measured strains are derived to recover the data lost due to unexpected errors in long-term measurement during construction. The proposed technique is applied to recovery of axial strain data of a mega column in an irregular building structure du...

PURPOSE This study aims to compare the biomechanical properties of the novel pedicle screw and plate system with the traditional rod system in asymmetrical posterior stabilization for minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). We compared the immediate stabilizing effects of fusion segment and the strain distribution on the vertebral body. METHODS Seven fresh calf lu...

A structure-based model that accurately predicts micro- or macromechanical behavior of blood vessels is necessary to understand vascular physiology. Based on recently measured microstructural data, we propose a three-dimensional microstructural model of coronary adventitia that incorporates the elastin and collagen distributions throughout the wall. The role of ground substance was found to be ...

We analyze the stability of homogeneous simple tensile/compressive deformations of an isotropic heat-conducting thermoviscoplastic bar by studying the growth of infinitesimal perturbations superimposed upon a homogeneous deformation. The smallest axial strain at which the superimposed perturbation has a positive initial growth rate is called the instability strain. Two criteria are used to dete...

In this paper, transverse and longitudinal vibration of nonlinear plate under exciting of orbiting mass is considered based on first-order shear deformation theory. The nonlinear governing equation of motion are discretized by the finite element method in combination with Newmark’s time integration scheme under von Karman strain-displacement assumptions. For validation of method and formulation...

The parametric resonance of the axial vibrations of a cantilever pipe conveying harmonically perturbed two-phase flow is investigated using the method of multiple scale perturbation. The nonlinear coupled and uncoupled planar dynamics of the pipe are examined for a scenario when the axial vibration is parametrically excited by the pulsating frequencies of the two phases conveyed by the pipe. Aw...

In this paper, semi-analytical method for asymmetrical eccentrically stiffened FGM cylindrical shells under external pressure and surrounded by a linear and non-linear elastic foundation is presented. The proposed linear model is based on two parameter elastic foundation Winkler and Pasternak. According to the von Karman nonlinear equations and the classical plate theory of shells, strain-displ...

This article describes coherent gradient sensing ~CGS! as an optical, full-field, real-time, nonintrusive, and noncontact technique for the measurement of curvatures and nonuniform curvature changes in film–substrate systems. The technique is applied to the study of curvature fields in thin Al films ~6 mm! deposited on thin circular silicon wafers ~105 mm! of ‘‘large’’ in-plane dimensions ~50.8...

A major objective of the theory of defects is to relate the mechanical behaviour of macroscopic materials to the spatio-temporal evolution of the microstructure. The present paper deals with the dislocation-dynamical foundations of plastic instabilities and the propagation of slip in coherent plastic deformation modes (solitary plastic waves). Solitary waves arise from a proper balance between ...