Keywords: Reaction–diffusion equations Pulsating wave fronts KPP and monostable nonlinearities Uniqueness a b s t r a c t We establish the uniqueness of pulsating wave fronts for reaction–diffusion equations in time periodic media with monostable nonlinearities. For the Kolmogorov–Petrovsky– Piskunov (KPP) type nonlinearity, this result provides a complete classification of all types of KPP pul...

Introduction: The purpose of this study was to compare the accuracy of the torque wrenches used in different dental implant systems. Methods: We evaluated 42 torque wrenches used in different dental clinics in Mashhad, Iran, using a digital torque meter (Mark 10). High (25, 30 and 35 N·cm) and low (15 N·cm) levels of torque were examined. Ten tests were performed on each wrench, and the mean va...

We have performed an infrared study of pulsating B stars. The main conclusion is that none of the 163 (non-)radial pulsators shows an IR excess flux due to free-free emission, despite the fact that the sample contains several rapid rotators. Two β Cep stars and two slowly pulsating B stars do exhibit an unexpected infrared colour excess at 12 μm. The small IR excess of the B 2 IV β Cep star HD ...

We present a classification of 267 new variable Btype stars discovered by Hipparcos. We have used two different classification schemes and they both result in only a few new β Cephei stars, a huge number of new slowly pulsating B stars, quite some supergiants with αCyg-type variations and variable CP stars, and further some new periodic Be stars and eclipsing binaries. Our results clearly point...

PURPOSE Retinal venous pulsation detection is a subjective sign, which varies in elevated intracranial pressure, venous obstruction and glaucoma. To date no method can objectively measure and identify pulsating regions. METHOD Using high resolution video-recordings of the optic disk and retina we measured fluctuating light absorption by haemoglobin during pulsation. Pulsation amplitude was ca...

Aims. We test the hypothesis that the pulsations in sdB stars are correlated with the surface abundances of iron-group elements. Any correlation might explain why, when given two spectroscopically similar stars, one will pulsate while the other will not. Methods. We have obtained high-resolution ultraviolet spectra two pulsating and three non-pulsating sdB stars using the Space Telescope Imagin...

Pulsating technology joins ultra-efficient screens for the utmost in cuttings treatment, fluid recovery

Pulsations discussed will begin at the “top” of the instability strip with pulsating red giants and Miras, which are evolved stars nearing their own demise. The next discussed will be the Cepheids, both the “Classical” ones as well as the W Virginis (Population II stars). While moving down the instability strip of the HR Diagram, the next major type of variable (pulsating) star are the RR Lyrae...

In this paper, the mechanism of improvement of formability in pulsating hydroforming of T-shape tubes is investigated by the finite element simulation and experiment. It is shown that local thinning was prevented by oscillating the internal pressure, because the protrusion is formed gradually by the prevention of sharp bulging. In the hydroforming, for the pulsating pressure, several steps occu...

In this study, two-dimensional pulsating unsteady flow of nanofluid through a rectangular channel with isothermal walls is investigated numerically. The set of resultant algebraic equations is solved simultaneously using SIMPLE algorithm to obtain the velocity and pressure distribution within the channel. The effects of several parameters, such as volume fraction of different nanoparticles, Rey...