This paper considers the problem of damping the oscillation of a plane pendulum by moving the pivot in the vertical plane and the weight along the rod of the pendulum, with limited amplitudes. Conditions for stability of the motion of the pendulum are derived using energybased methods, and based on them energy-based controls satisfying the amplitude constraints are developed, which move the piv...

The proportional and derivative nonlinear potential feedback controls via piezoelectric sensor and actuator layers are used. A simple and consistent model combining the geometrical nonlinear affects and the feedback control of a piezoelectric/elastic/piezoelectric sandwich beams is derived. A mathematical methodology based on the multiple scales method for nonlinear vibration control of seconda...

Background: Many people suffer from nerve injury. The time consuming nature of the treatments makes the condition worse. Therefore, finding a way to accelerate the process of nerve repair is very important.Objective: To determine the effect of ultrasound on the acceleration of crushed peripheral nerve regeneration.Methods: The experimental model included crushed rat’s sciatic nerve. 40 rats w...

This study deals with tree-like structures that mimic a trunk with either first-order branches or both first and second-order branches of a sympodial tree. The corresponding mechanical model comprises physical pendula coupled with torsional springs and viscous dampers. Natural frequencies and modal shapes are obtained analytically and the effects of a branching angle and a stiffness ratio on th...