Fast-moving legged animals bounce along the ground with spring-like legs and agilely traverse variable terrain. Previous research has shown that hopping and running humans maintain the same bouncing movement of the body's centre of mass on a range of elastic surfaces by adjusting their spring-like legs to exactly offset changes in surface stiffness. This study investigated human hopping on damp...

The string pendulum consists of a mass attached to the end of an inextensible string which is fastened to a support. Applying an external forcing to the pendulum’s support is motivated by understanding the behavior of suspension bridges or of tethered structures during earthquakes. The forced string pendulum can go from taut to slack states and vice versa, and is capable of exhibiting interesti...

anaerobic treatment methods are more suitable for the treatment of concentrated wastewater streams, offer lower operating costs, the production of usable biogas product. the aim of this study was to investigate the performance of an anaerobic fluidized bed reactor (afbr)-aerobic moving bed bio reactor (mbbr) in series arrangement to treat currant wastewater.the bed materials of afbr were cylind...

Present time the main issue of automobile industry are weight reduction. The automobile industry has looking for any implementation or modification to reduce the weight of the vehicle. The suspension leaf spring is one of the potential items for weight reduction in automobile as it accounts for 10% to 20% of the unsprung weight. The introduction of composite leaf spring made of glass fiber rein...

• A model of locally resonant piezoelectric/elastic phononic crystal double-layer nanobeam is proposed. Band structures with nonlocal effects are calculated by plane wave expansion method. Symmetric and antisymmetric bands divided. Influences various parameters on band discussed. The paper proposed a (LR) (PC) periodically attached “spring-mass” resonator additional spring between upper lower n...

the nonlocal nonlinear buckling of a double layer graphene sheet (dlgs) covered by zinc oxide (zno) piezoelectric layers is investigated in this study. the surrounding circumstances of the system are considered as a pasternak foundation including spring constants and a shear layer. graphene sheets are subjected to longitudinal magnetic field and biaxial forces. on the other hand, the zno piezoe...

These experiments determined the magnitude of loads that rhinoceros beetles (Scarabaeidae) can carry and also the metabolic energy required for carrying loads. I hypothesized that, like many other animals, these beetles would have metabolic rates in direct proportion to the total load (body mass plus added mass). Eight beetles (Xylorctes thestalus) walked at 1 cm s-1 on a motorized treadmill en...

Two noncanonical Hamiltonian models are presented for the dynamics of a rigid body with an constrained moving point mass. One of these models is used to analyze stability of steady principal axis rotation of a rigid body with a spring-mass oscillator. The analysis gives necessary and sufficient conditions for stability of steady major axis rotation, as well as sufficient conditions for instabil...

in this paper, the dynamic simulation for a high pressure regulator is performed to obtain the regulator behavior. to analyze the regulator performance, the equation of motion for inner parts, the continuity equation for diverse chambers and the equation for mass flow rate were derived. because of nonlinearity and coupling, these equations are solved using numerical methods and the results are ...