An experimental investigation of the shock-induced interfacial instability (RichtmyerMeshkov instability) is undertaken in an effort to study temporal evolution of interfacial perturbations in the nonlinear regime. The experiments are performed in a vertical shock tube with a square cross-section. A membraneless interface is prepared by retracting a sinusoidally shaped metal plate initially sep...

We conducted a human fear conditioning experiment in which three different color cues were followed by an aversive electric shock on 0, 50, and 100% of the trials, and thus induced low (L), partial (P), and high (H) shock expectancy, respectively. The cues differed with respect to the strength of their shock association (L < P < H) and the uncertainty of their prediction (L < P > H). During con...

The process of cosmic-ray first-order Fermi acceleration at relativistic shock waves is studied with the method of Monte Carlo simulations. The simulations are based on numerical integration of particle equations of motion in a turbulent magnetic field near the shock. In comparison to earlier studies, a few “realistic” features of the magnetic field structure are included. The upstream field co...

This paper presents a geometric measure that can be used to gauge the similarity of 2D shapes by comparing their skeletons. The measure is defined to be the rate of change of boundary length with distance along the skeleton. We demonstrate that this measure varies continuously when the shape undergoes deformations. Moreover, we show that ligatures are associated with low values of the shape-mea...

The shock graph is an emerging shape representation for object recognition, in which a 2-D silhouette is decomposed into a set of qualitative parts, captured in a directed acyclic graph. Although a number of approaches have been proposed for shock graph matching, these approaches do not address the equally important indexing problem. We extend our previous work in both shock graph matching and ...

We present a model for the non-thermal radio emission from bright O stars, in terms of synchrotron emission from wind-embedded shocks. The model is an extension of an earlier one, with an improved treatment of the cooling of relativistic electrons. This improvement limits the synchrotron-emitting volume to a series of fairly narrow layers behind the shocks. We show that the width of these layer...

The influence of the plug shape on the performance of an aerospike nozzle thrust force is studied in different back pressure conditions. To generate smooth plug contours, Cubic B-Spline technique is employed. In the current research, basis functions are obtained using Deboor’s relation. The flow field around the aerospike nozzle is investigated implementing various shapes and the best of the ge...

1 The observed spectrum of a supernova remnant (SNR) is a superposition of many " local " spectra emitted by regions of SNRs that are under different physical conditions. The question remains as to whether the broadening of the high-energy end of the observed nonthermal spectrum of SNRs, like in G347.3-0.5 and SN 1006, can be an artifact of observations or it is a consequence of the microphysic...

The immunofluorescence patterns for actin, myosin, calmodulin and tubulin were observed in Euglena gracilis Klebs strain Z during the biological clock-controlled shape changes observed with division-synchronized cells, and during two shock responses that induce cell rounding. The fluorescence patterns for actin, myosin, calmodulin and tubulin show a high degree of coincidence and are visualized...

In this paper, we have investigated the effect of uncertainties on the interactions of a bubble with a shock, based on a widely studied experiment case of helium-air shockbubble interaction. Gas contamination inside the bubble and deformation of the initial bubble shape were selected as the uncertainty parameters, and the statistics of the interface evolution and the primary baroclinic vorticit...