conclusions the study revealed the significance of anthropometric variables related to heading, such as age and head perimeter. therefore, it was concluded that these variables should be considered when teaching and practicing the heading technique with players of different ages and anthropometric sizes. results significant correlations existed between the force exerted on the head during headi...

BACKGROUND Soccer heading has been proposed as a potential cause of cerebral dysfunction. OBJECTIVE To examine the acute effects of two types of soccer heading on postural control. METHODS Collegiate soccer players were randomly assigned to one of four groups: control, linear heading, simulated rotational heading, or rotational heading. Each subject completed a baseline postural stability a...

Auxiliary ventilation of the blind development heading in underground mines is one of the most challenging work activities amongst mining underground operations. The auxiliary forcing ventilation system provides positive pressure, cooling, controlling gas layering, and removing diesel fumes and dust levels from development headings, stopes, and services facilities. The effectiveness of the auxi...

We present a collocation method to obtain the approximate solution of Troesch's problem which arises in the confinement of a plasma column by radiation pressure and applied physics. By using the Christov rational functions and collocation points, this method transforms Troesch's problem into a system of nonlinear algebraic equations. The rate of convergence is shown to be exponential. The numer...

we present a collocation method to obtain the approximate solutionof troesch's problem which arises in the confinement of a plasmacolumn by radiation pressure and applied physics. by using thechristov rational functions and collocation points, this methodtransforms troesch's problem into a system of nonlinear algebraicequations. the rate of convergence is shown to be exponential. then...

This paper presents the results of modeling tests of the Effect of Confinement Pressure on footing bearing capacity of two kinds of square and strip footing. Footings bearing capacity depends upon many factors including soil kind, depth, form and kind of loading. Soil behavior is variable regarding the kind of loading and the kind of deformations in that can have great importance in the amount ...

Gas mixtures containing c-C4F8 /Ar are commonly used for the plasma etching of dielectric materials such as SiO2 . To quantify the dependence of fundamental plasma parameters of systems using these mixtures, inductively coupled plasmas in the pressure range of 6–20 mTorr, with and without magnetic confinement, were investigated. Measurements were also made in pure Ar and O2 to provide a compari...

The fluctuation pressure of a lipid-bilayer membrane is important for the stability of lamellar phases and the adhesion of membranes to surfaces. In contrast to many theoretical studies, which predict a decrease of the pressure with the cubed inverse distance between the membranes, Freund suggested very recently a linear inverse distance dependence [Proc. Natl. Acad. Sci. USA 110, 2047 (2013)]....

In this article the effects of different engineering parameters of rf-driven ion sources with an external spiral antenna and a quartz rf window are studied. This article consists of three main topics: the effect of source geometry on the operation gas pressure, the effect of source materials and magnetic confinement on extracted current density and ion species, and the effect of different anten...