in the present work, a prototype of a new type of solar collectors, which called direct absorption solar collector, was built and its thermal performance is experimentally compared with conventional flat plate solar collector under transient and steady state conditions. different volume fractions of multi wall carbon nanotubes in water and ethylene glycol mixture (70%:30% in volume) were used a...

This paper deals with the experimental results of a xenon flash-lamp pumped passively Q-switched Nd:YAG laser using Cr4+:YAG saturable absorber. The need of a laser cavity to be integrated into a time-of-flight laser range finder is of great interest as an experimental investigation of several laser resonators. Two types of laser resonator, with different lengths, have been studied: the flat-fl...

In this paper, a new set of spline functions called ``Flat End Fuzzy Spline" is defined to interpolate given fuzzy data. Some important theorems on these splines together with their existence and uniqueness properties are discussed. Then numerical examples are presented to illustrate the differences between of using our spline and other interpolations that have been studied before.

Optimal linear controllers and high computational non-linear controllers are normally applied to control the nonlinear systems. Flatness control method is a control technique for linear systems as well as nonlinear systems by static and dynamic feedback namely as endogenous dynamic feedback. This method takes into account the non-linear behavior of the process while preventing complicated compu...

introduction:balance impairments are one of the important complications in subjects with functional ankle instability (fai) that has been reported to be associatedwithjoint mechanoreceptorinjuries. textured insole effecting on plantar cutaneous of the feet, may improve postural control and reduce the risk of injury in subjects with fai.the aim of this study therefore was to investigate the effe...

Background: Flexible Flat Foot (FFF), a common foot deformity decreasing medial longitudinal arch height is often comorbid with subtalar joint pronation causing physical activity difficulties in this population. Among the orthotic insoles prescribed for improving foot function, foot orthoses with medial heel skive technique have a limited research background. The present study aimed to investig...

In this paper‎, ‎we study the class of rings in which every $P$-flat‎ ‎ideal is flat and which will be called $PFF$-rings‎. ‎In particular‎, ‎Von Neumann regular rings‎, ‎hereditary rings‎, ‎semi-hereditary ring‎, ‎PID and arithmetical rings are examples of $PFF$-rings‎. ‎In the context domain‎, ‎this notion coincide with‎ ‎Pr"{u}fer domain‎. ‎We provide necessary and sufficient conditions for‎...