Models of the dynamic response of the lumbar spine have been used to examine vertebral fractures (VFx) during falls and whole body vibration transmission in the occupational setting. Although understanding the viscoelastic stiffness or damping characteristics of the lumbar spine are necessary for modeling the dynamics of the spine, little is known about the effect of intervertebral disk degener...

nonlinear hunting speeds of railway vehicles running on a tangent track are analytically obtained using hopf bifurcation theory in this paper. the railway vehicle model consists of nonlinear primary yaw dampers, nonlinear flange contact stiffness as well as the clearance between the wheel flange and rail tread. linear and nonlinear critical speeds are obtained using bogoliubov method. a compreh...

Self-avoiding walks self-interacting via nearest neighbours (ISAW) and self-avoiding trails interacting via multiply-visited sites (ISAT) are two models of the polymer collapse transition of a polymer in a dilute solution. On the square lattice it has been established numerically that the collapse transition of each model lies in a different universality class. It has been shown that by adding ...

To effectively improve the tire grounding behaviors of wheelchair robots, an analytical method is proposed to analyze and optimize the tire grounding safety. Firstly, taking the cushion and tires as the vibration isolation elements with stiffness and damping, the vertical vibration model of the human-wheelchair robot is established. Then, taking the random excitation as the typical input, the f...

Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mec...

In this paper we present the first extension of the backstepping methods developed for control of parabolic PDEs (modeling thermal, fluid, and chemical reaction dynamics, including Navier-Stokes equations and turbulence) to secondorder PDE systems (often referred loosely as hyperbolic) which model flexible structures and acoustic. We introduce controller and observer designs capable of adding d...

In the inelastic time history analyses of structures in seismic motion, part of the seismic energy that is imparted to the structure is absorbed by the inelastic structural model, and Rayleigh damping is commonly used in practice as an additional energy dissipation source. It has been acknowledged that Rayleigh damping models lack physical consistency and that, in turn, it must be carefully use...