Dense record sections from deep earthquakes in Fiji and Argentina recorded on hundreds of short-period stations in California at distances of 81 o to 85° are used to investigate the detailed P wave velocity structure above the core-mantle boundary (CMB). In the Fiji data a secondary phase arriving 2 to 4 s after the direct P is identified as a precursor to PeP. This phase provides good evidence...

the aim of this paper is to present a numerical method for singularly perturbed convection-diffusion problems with a delay. the method is a combination of the asymptotic expansion technique and the reproducing kernel method (rkm). first an asymptotic expansion for the solution of the given singularly perturbed delayed boundary value problem is constructed. then the reduced regular delayed diffe...

Background: This paper explores the impact of thermal radiation on boundary layer flow of dusty hyperbolic tangent fluid over a stretching sheet in the presence of magnetic field. The flow is generated by the action of two equal and opposite. A uniform magnetic field is imposed along the y-axis and the sheet being stretched with the velocity along the x-axis. The number density is assumed to be...

Passive control of hypersonic boundary-layer transition using porous coatings has been studied by theoretical analyses, experiments, and numerical simulations. It was found that porous coating stabilizes Mack’s second mode and destabilizes Mack’s first mode. However, there are only few studies on the stabilization efficiency of porous coating. And no work has been reported about the thermochemi...

We have performed numerical simulations of the atmosphere for typical daytime convective conditions at Chajnantor, and derived the resulting wet and dry contributions to the atmospheric phase fluctuations. The simulations show that: ◦ Dry phase fluctuations are concentrated in two layers – near to the ground, and at the temperature inversion. The wet fluctuations are concentrated at the inversi...

The threshold electric field E(th) for a transition from the anticlinic to the synclinic phase of enantiomeric mixtures of the liquid crystal TFMHPOBC was measured as a function of temperature T and enantiomeric excess X. For small X the phase boundary curve on a temperature-electric-field phase diagram exhibits the phase sequence synclinic-anticlinic-reentrant synclinic on decreasing the tempe...

Measurements of frequency spectra of pressure along a wind-tunnel wall have been made by single microphones and by a longitudinal array of four flush 0.8-inch circular microphones connected with alternating and with common phase. The alternating-phase array was designed to suppress by its wavenumber filtering the background acoustic duct noise at frequencies near 3 kHz. The measured levels set ...

The dynamics of an ensemble of linear disturbances in boundary-layer flows at various Reynolds numbers is studied through an analysis of the transport equations for the mean disturbance kinetic energy and energy dissipation rate. Effects of adverse and favorable pressure-gradients on the disturbance dynamics are also included in the analysis. Unlike the fully turbulent regime where nonlinear ph...