near-surface variations can be very complex and may distort amplitudes and arrival times of the reflections events from target reflectors. near-surface complexities include topographic variations, near-surface irregularities, variations in soil conditions and the weathered layer. these perturbations generally have a significant impact on seismic recordings. although there is a general agreement...

An approximate analytical solution is obtained for hypersonic flow past a slender elliptic cone using second-order perturbation techniques in spherical coordinate systems. The analysis is based on perturbations of hypersonic flow past a circular cone aligned with the free stream, the perturbations stemming from the small cross-section eccentricity. By means of hypersonic approximations for the ...

We consider the influence on the surface critical behaviour of a quantum Ising chain of quenched random surface perturbations decaying as a power of the distance from the surface (random Hilhorst–van Leeuwen models). We study, analytically and numerically, the multiscaling behaviour of the surface magnetization and the surface energy density in the case of marginal perturbations.

AbstractIntroduction Silicone gel breast implants are used for breast reconstruction post mastectomy. In the event of cancer recurrence, the radiation oncologists are forced to irradiate through the prosthesis device. Due to prosthesis higher atomic number dose perturbations occur during treatment. This study determined the influence of silicone gel thickness on the photon beam distribution. Ma...

Objectives Drawing on new (2011-12) and previous (1993-5, 2000-1 and 2007-8) data on suicidal behaviour reported by the Belgian Network of Sentinel General Practices (SGP), we describe trends in the key characteristics of suicidal events. We also examine patient age-related trends in the on-site attendance of sentinel general practitioners (GPs) as first professional caregivers following suicid...

Walking on uneven surfaces or while undergoing perturbations has been associated with increased gait variability in both modeling and human studies. Previous gait research involving continuous perturbations has focused on sinusoidal oscillations, which can result in individuals predicting the perturbation and/or entraining to it. Therefore, we examined the effects of continuous, pseudo-random s...

the paper is concerned with the bifurcation of limit cycles in general quadratic perturbations of a quadratic reversible and non-hamiltonian system, whose period annulus is bounded by an elliptic separatrix related to a singularity at infinity in the poincar'{e} disk. attention goes to the number of limit cycles produced by the period annulus under perturbations. by using the appropriate p...