In the present paper, time dependent creep behavior of hollow circular rotating cylinders made of exponentially graded material (EGM) is investigated. Loading is composed of an internal pressure, a distributed temperature field due to steady state heat conduction with convective boundary condition and a centrifugal body force. All the material properties are assumed to be exponentially graded a...

The present paper will describe an approach for the simultaneous real-time compensation of hysteresis, creep and force-dependence effects of a piezoelectric stack actuator by a feed-forward controller. The basis of the feed-forward controller is given by so-called complex creep and hysteresis operators, which when adequately implemented, lead to a precise model of the creep and hysteresis chara...

The study is focused on the effect of transient external force induced by a passing seismic wave on fault motion in different creep regimes. Displacement along the fault is represented by the movement of a spring-block model, whereby the uniform and oscillatory motion correspond to the fault dynamics in post-seismic and inter-seismic creep regime, respectively. The effect of the external force ...

The oesophagus serves to transport food and fluid from the pharynx to the stomach. Oesophageal function is usually evaluated by means of manometry which is a proxy of the force in the radial direction. However, force measurements in the axial direction will provide a better measure of oesophageal transport function. The aim of this study was to develop a probe based on electrical impedance meas...

We report the simultaneous characterization of timeand force-dependent mechanical properties of adherent cells in the physiologically relevant regime of large forces. We used magnetic tweezers to apply forces to magnetic beads bound to the cytoskeleton, and recorded the resulting deformation (creep response). The creep response followed a weak power law at all force levels. Stress stiffening an...

The actin cytoskeleton helps maintain structural organization within living cells. In large X. laevis oocytes, gravity becomes a dominant force and is countered by a nuclear actin network that prevents liquid-like nuclear bodies from immediate sedimentation and coalescence. However, nuclear actin's mechanical properties, and how they facilitate the stabilization of nuclear bodies, remain unknow...

This paper characterized bovine extraocular muscles (EOMs) using creep, which represents long-term stretching induced by a constant force. After preliminary optimization of testing conditions, 20 fresh EOM samples were subjected to four different loading rates of 1.67, 3.33, 8.33, and 16.67%/s, after which creep was observed for 1,500 s. A published quasilinear viscoelastic (QLV) relaxation fun...

Switching dynamics of ferroelectric materials are governed by the response of domain walls to applied electric field. In epitaxial ferroelectric films, thermally-activated 'creep' motion plays a significant role in domain wall dynamics, and accordingly, detailed understanding of the system's switching properties requires that this creep motion be taken into account. Despite this importance, few...

We study the creep motion of an elastic string in a two-dimensional pinning landscape by means of Langevin dynamics simulations. We find that the velocity-force characteristics are well described by the creep formula predicted from phenomenological scaling arguments. We analyze the creep exponent mu and the roughness exponent zeta. Two regimes are identified: when the temperature is larger than...

In vivo measurements of the viscoelastic properties of breast tissue are described. Ultrasonic echo frames were recorded from volunteers at 5 fps while applying a uniaxial compressive force (1-20 N) within a 1 s ramp time and holding the force constant for up to 200 s. A time series of strain images was formed from the echo data, spatially averaged viscous creep curves were computed, and viscoe...