An application is presented of a recently proposed system identification method for buildings that takes into account the effects of soil-structure interaction and the coupling of the horizontal and rocking motions of the foundation. The method gives the uncoupled structural fixed-base frequency f1 and rigid-body rocking frequency fR using data only from two horizontal sensors (at base and roof...

Recent studies have highlighted the potential benefits of inelastic foundation response during seismic shaking. According to an emerging seismic design scheme, termed rocking isolation, the foundation is intentionally under-designed to promote rocking and limit the inertia transmitted to the structure. Such reversal of capacity design may improve the seismic performance, drastically increasing ...

For centuries, rocking has been used to promote sleep in babies or toddlers. Recent research suggested that relaxation could play a role in facilitating the transition from waking to sleep during rocking. Breathing techniques are often used to promote relaxation. However, studies investigating head motions and body rotations showed that vestibular stimulation might elicit a vestibulo-respirator...

Complete chattering occurs when a structure undergoes theoretically infinite sequence of impacts in finite time, that eventually bring the to state persistent (continuous) contact. This study investigates conditions under which rigid rocking block complete subjected sinusoidal ground excitation. The analysis explains how acceleration amplitude excitation affects time. It also proves there exist...

Bartussek, Hänggi and Kissner studied a rocking ratchet system, in which a Brownian particle is subject to an asymmetric periodic potential together with an oscillating force, and found that the direction of the macroscopic current can be reversed by changing the parameter values characterizing the model [Europhys. Lett., 28 (1994) 459]. In this letter, we apply their ratchet theory to a rotary...

Grazing-incidence X-ray diffraction and rocking scans have quantified the structure of poly(3-hexylthiophene) and [6,6]-phenyl-C(61)-butyric acid methyl ester in the active layers of organic solar cells. Our study reveals that the device J(SC) correlates with the local structural development of pure PCBM and, to second order, the extent of out-of-plane P3HT π-stacking.

We derive explicit results for the asymptotic probability density and drift velocity in systems driven by dichotomous Markov noise, including the situation in which the asymptotic dynamics crosses unstable fixed points. The results are illustrated on the problem of the rocking ratchet.

The evolution of polarization and spin angular momentum (SAM) in periodically rocking superlattices (PRS) is investigated. Unlike in the birefringent crystal, they exhibit unusual properties. The evolution of polarization shows many remarkable trajectories and the SAM oscillates inside the PRS. The results may find applications in polarization-state or optical SAM control.