The experimental study introduces an unload-induced direct-shear model to investigate the frictional slip of a layer of simulated granular gouges induced by the combination of a decreasing normal stress and a constant shear stress. A frictional equilibrium state of the gouge layer is initially established under fixed normal and shear stresses. The normal stress is proposed to decrease at a cons...

1. Abstract In this work a multi-criteria optimization model is developed to obtain the optimal geometry of the femoral component of a hip prostheses. The objective function minimizes both the relative tangential displacement and the contact normal stress. For cementless stems, these two factors are relevant for the prostheses stability and therefore for the implant success. In fact, “small” re...

Unexpected sudden perturbations challenge postural equilibrium and require reactive compensation. This study aimed to assess interaction effects of the direction, displacement and velocity of perturbations on electromyographic (EMG) activity, centre of pressure (COP) displacement and joint kinematics to detect neuromuscular characteristics (phasic and segmental) and kinematic strategies of comp...

i n the past decades, the effect of different tax amendments on various economic issues has been studied. the majority of these studies have avoided considering shadow economy as part of the calculation and analysis, and an issue, which has received little attention, is the relationship between green tax reforms and shadow economy, as for informal labor, which is well-connected to unemployment ...

in this paper, we introduce fractional order of a planar fractional prey-predator system with a nonmonotonic functional response and anti-predator behaviour such that the adult preys can attack vulnerable predators. we analyze the existence and stability of all possibleequilibria. numerical simulations reveal that anti-predator behaviour notonly makes the coexistence of the prey and predator po...

We update the method of the Holmberg & Flynn (2000) study, including an updated model of the Milky Way’s interstellar gas, radial velocities, an updated reddening map, and a careful statistical analysis, to bound the allowed surface density and scale height of a dark disk. We pay careful attention to the self-consistency of the model, including the gravitational influence of the dark disk on ot...

We update the method of the Holmberg & Flynn (2000) study, including an updated model of the Milky Way’s interstellar gas, radial velocities, an updated reddening map, and a careful statistical analysis, to bound the allowed surface density and scale height of a dark disk. We pay careful attention to the self-consistency of the model, including the gravitational influence of the dark disk on ot...

Ground settlement is often the most serious concern when tunneling under an old city with numerous historic monuments. A successful engineering design under these conditions would require getting the most out of the ground strength parameters and avoiding any weakening maneuver throughout the operation. Knowing that surface settlement is highly affected by tunneling parameters in EPB shield tun...