Ballasted tracks are common in the railway system as a means of providing necessary support for sleepers and rails. To keep them operational, tamping other maintenance actions performed based on track geometry measurements. Ballast particle rearrangement, which is caused by train load, one most important factors leading to degradation. As result, when planning maintenance, it vital predict beha...

To enhance the stability of continuous welded rail (CWR) tracks, frictional sleepers have been developed. The are new types with grooves on bottom, and different bottom improve lateral resistances at magnitudes. In this study, single sleeper push test (SSPT) its model discrete element method (DEM) were carried out to confirm how much arrowhead groove (AGF) increases resistance ballasted track. ...

BACKGROUND Dual-channel transmit technology improves the image quality in cardiovascular magnetic resonance (CMR) at 3 T by reducing the degree of radiofrequency (RF) shading over the heart by using RF shimming. Further improvements in image quality have been shown on a dual-transmit system using high permittivity pads. The aim of this study is to investigate the transmit field (B 1 (+)) homoge...

Knuckle pads occur from benign thickening of the skin, principally the epidermis, and are occasionally seen in children. Despite the name, knuckle pads most commonly overlie the proximal interphalangeal joints. They must be differentiated from a variety of other cutaneous abnormalities. There is no consistently effective treatment, but knuckle pads have been reported to resolve spontaneously in...

Abstract A new time-delayed periodic boundary condition (PBC) has been proposed for discrete element modelling (DEM) of structures subject to moving loads such as railway track based on a box test which is normally used an testing model. The PBC approached by predicting forces acting ghost particles with the consideration different loading phases adjacent sleepers whereas normal simply gives sa...

BACKGROUND Primary antibody deficiencies (PADs) are heterogeneous group of disorders, characterized by hypogammaglobulinemia and increased susceptibility to recurrent infections. To evaluate the diagnostic delay in Iranian PADs in association with their infections, we scored such manifestations to find an association between such delay and the scoring system. METHODS Forty-eight patients with...

It is well known that the regular continued fraction expansion of a quadratic irrational is symmetric about its centre; we refer to this symmetry as horizontal. However, an additional vertical symmetry is exhibited by the continued fraction expansions arising from a family of quadratics known as Schinzel sleepers. This paper provides a method for generating every Schinzel sleeper and investigat...