The high strain rate behavior of two cellular materials was investigated using a quasi-static loading stage and a Kolsky bar apparatus. The yield stress of these core materials under dynamic loading was found higher than in quasi-static loading. However, the plateau stress after yielding is not so sensitive to strain rate. For Aluminum foam materials, the deformation was more localized for quas...

Piezoelectric materials are used in many engineering application. When modeling piezoelectric materials the standard assumption is that the electromagnetic field which is used to actuate the piezoelectric material is quasi static. In this paper we show that although the assumption of a quasi static electrical field is valid when one is interested in simulating a piezoelectric material, this ass...

The study of mechanical behavior of the structural steel S400 under quasi- static and dynamic loading has been the subject of this investigation. In oder to obtain different stress - triaxiality conditions the specimens were notched with 1, 1.5, 2 and 3.5 mm notch radius. The results of fractography show as the velocity of tension increases, ductility reduces and a ductile-brittle transition oc...

The simulation of the store separation using the automatic coupling of dynamic equations with flow aerodynamics is addressed. The precision and cost (calculation time) were considered as comparators. The method used in the present research decreased the calculation cost while limiting the solution error within a specific and tolerable interval. The methods applied to model the aerodynamic force...

Oscillatory behavior in a chain of masses connected by springs with continuous but non-monotonic spring forces can be induced under quasi-static loading. Insight into the birth of this behavior is obtained from a single mass system. A bifurcation study shows the potential for equilibrium jumps between multiple equilibria. As such, the transients occurring under quasi-static loading do not conve...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Jiaran Qi Name of the doctoral dissertation Dispersion of dielectric composites: quasi-dynamic characterizations and applications Publisher School of Electrical Engineering Unit Department of Radio Science and Engineering Series Aalto University publication series DOCTORAL DISSERTATIONS 61/2011 Field of research Electromagneti...

The elastic pressure/volume (P/V) curve obtained by the multiple linear regression (MLR) technique using a new model, was compared with the quasi-static P/V points obtained by the rapid airway occlusion technique. Seven infants were studied during mechanical ventilation using a pressure controlled mode. The resistive pressure was subtracted from airway opening pressure, thus determining the ela...

this study aims to numerically investigate on the crashworthiness of thin-walled square tubes by consideration of 3-d oblique loading. in this type of loading, direction of loading is defined by using two spatial angles relative to the position of the tube. to this aim, finite element (fe) analysis is employed to simulate the loading for 8 different numerical models with different loading orien...

The problem of unbounded uniaxial chiral omega media in the presence of both static electric and magnetic point charges is investigated. For this purpose scalar electric and magnetic potentials in these media are introduced. Using these potentials, the corresponding electric and magnetic fields are determined. The similar problem of static electric and magnetic current sources with the goal of ...