Influence Of Dynamic Interaction Research Articles

Study on Seismic Response Characteristics of Hinge-Type Slope

Considering the influence of dynamic interaction between soil and structure, a finite element analysis model of nonlinear dynamic interaction of hinge type slope is established. Then, numerical simulation towards its seismic response has been carried out. Analysis on stress, acceleration and response characteristics of relative horizontal displacement under different seismic oscillation are conducted. Whose results represent that when at the same intensity and spectrum of earthquake motion, the maximum dynamic stress in the middle and upper part of slope is larger while the acceleration and horizontal displacement of the top and bottom is higher. If under earthquake motion with the same intensity and different spectrum, the dynamic response of slope under Loma Prieta wave is larger than that under Kobe wave. Considering the seismic response characteristics of slope, its top and bottom are weak areas. Therefore, attention should be paid to these places in seismic design, same emphasis should also be given to the middle and middle-upper part.

Spin-polarized current-induced excitations in a coupled magnetic layer system

The influence of dynamic interactions on the spin-polarized current-induced steady state oscillations has been studied numerically for a spin torque oscillator that is composed of a free layer and a synthetic antiferromagnetic (SAF) pinned layer. Two types of dynamical interactions have been considered. The first is the exchange interaction between the two layers that constitute the SAF pinned layer. The second is a mutual spin torque interaction between the free layer and the pinned SAF layer. Taking these interactions into account, the Landau-Lifshitz-Gilbert equation including the spin transfer torque has been solved simultaneously for all three layers in a macrospin approach. Besides the dynamic state diagram for such a coupled spin torque oscillator, three major results have been obtained for the dynamic excitation states: (1) the dynamic states are not in all cases steady state periodic oscillations but can present nonperiodic trajectories reminiscent of chaos, (2) due to the mutual spin torque interaction frequency jumps can occur which are interpreted in terms of resonance excitations and frequency locking between the free layer and SAF magnetizations, and (3) the acoustic-type steady state oscillations of the SAF differ from those of a single layer in that the frequency vs current dependence of the in-plane precession modes can show both redshift as well as blueshift. This is interpreted as a general property of the large-angle nonlinear dynamics of a SAF.

Influence of tractor—trailer interaction on assessment of road damaging performance

The influence of dynamic interaction between tractor and trailer on the assessment of the road damaging performance of heavy goods vehicles is investigated using simple mathematical models. Tractor and trailer damage indices are used to quantify the ‘in-service’ road damaging performance of a simulated fleet of vehicles with parametric variations typical of highway traffic in the United Kingdom. Simulated results of assessment tests on individual tractor—trailer combinations are correlated with the performance of the simulated vehicle fleet. The main aim is to establish the characteristics of a ‘standard’ semi-trailer to be used in the assessment of tractors, and a ‘standard’ tractor for testing semi-trailers. It is found that measurement of suspension ‘frequency’ gives the poorest correlation with the damage indices, while the ‘dynamic aggregate force coefficient’ gives the best correlation. Correlation achieved when assessing trailers is higher than when assessing tractors. Optimum specifications for standard test tractors and trailers to maximize test accuracy are determined.