An experimental and numerical study was carried out to investigate the heat transfer by natural convection in a three dimensional annulus enclosure filled with porous media (silica sand) between two inclined concentric cylinders with (and without) annular fins attached to the inner cylinder under steady state condition. The experiments were carried out for a range of modified Rayleigh number (0.2 ≤Ra*≤ 11) and extended to Ra*=500 for numerical study and for annulus inclination angle of (δ = 0˚, 30˚, 60˚ and 90˚). The numerical study was to give the governing equation under assumptions that used Darcy law and Boussinesq’s approximation and then it was solved numerically using finite difference approximation. It was found that t

     Solving problems via artificial intelligence techniques has widely prevailed in different aspects. Implementing artificial intelligence optimization algorithms for NP-hard problems is still challenging. In this manuscript, we work on implementing the Naked Mole-Rat Algorithm (NMRA) to solve the n-queens problems and overcome the challenge of applying NMRA to a discrete space set. An improvement of NMRA is applied using the aspect of local search in the Variable Neighborhood Search algorithm (VNS) with 2-opt and 3-opt. Introducing the Naked Mole Rat algorithm based on variable neighborhood search (NMRAVNS) to solve N-queens problems with different sizes. Finding the best solution or set of solutions within a plausible amount of t

Diffraction patterns formed by a ferronematic sample, which contains 4-(trans-4-n-hexylcyclohexyl)-isothiocyanatobenzene (6CHBT) liquid crystal doped with Fe₃O₄ rodlike magnetic nanoparticles, was studied. The studied mixture can be applicated as a liquid magnetic switch. The diffraction patterns were observed from the micro-lines scribed on the polymer layer, which was contained by the liquid crystal mixture cell, with dimensions of 4 nm for depth and 0.32 µm for width and 5000 line per 1 mm² in the case of absence and presence of the DC magnetic field. From the experimental results, it was observed that the application of the magnetic field caused more than 17% expansion in the diffraction patterns a

The research focuses on determining the role of customer relationship management in improving financial performance by surveying the opinions of a number of employees of a number of Iraqi private banks. The customer has become the focus of attention and the most important factors of success and profitability and competition. Therefore, decisions related to the customer are important decisions that support the process of making, And follow-up of administrative decisions, including financial decisions aimed at improving the financial performance of banks and distinguish them from competitors.    Thus, the techniques used in customer relations management programs to collect, analyze and use data and information have beco

Background: The purpose of this study was to verify the influence of post- pressing time of acrylic resin (immediate, 6, 12 and 24 hour) on the dimensional accuracy of denture base whish is a critical factor in the retention and stability of the complete denture that may occur during polymerization shrinkage. Materials and Methods: Forty maxillary stone casts were poured in plastic mold (Columbia Dentoform corp. NEW YORK, type III dental stone (Geastone, Zeus Sri Loc.Tamburine Roccastrada, GR, Italy). The stone casts were randomly assigned into 4 groups of 10 specimens each according to the post-pressing times into (immediate, 6, 12 and 24 h.). Heat cure acrylic resin denture base was constructed according to the previously mentioned pressi

The current paper aims at knowing the effect of  Exemplar of Wettli On Acquiring Grammatical Concepts Among Basic 7^th Class Female Students in Kurdish Language Grammar.

The current paper is confined to a sample of  Basic 7^th Class Female Students-  Khaniqin –belonged Morning schools for the academic year 2014-2015 . The sample amounted 50 female students  distributed on two sections ( A,B) . Section A represented  experimental group ( 24) female  students  studied according to the exemplar of ( Wettli) and (B) represented control group (26) female students who have studied with traditional method. The researcher has qualified between these two groups  b

The study included studying some of the optimum environmental conditions(temperature ,light intensity ) on the production of several green algae Scendesmus quadricauda and Chlorella vulgaris in a selected culture and municipal wastewater . The study also included the recording of growth rate ,doubling time and removal of phosphate and nitrate , maximum rate was recorded to the growth with minimum in doubling time and maximum removal rate of nitrogen-nitrate and phosor- phosphate in each selected culture and municipal wastewater in each species of green algae at 25 C? and a light intensity 380 µ E / m2 / s.

Titanium alloy (Ti-6Al-4V or Gr.23) was widely used as a dental alloy. In the current study, polymerization of eugenol (PE) on Gr.23 titanium alloys was conducted by an electrochemical process before and after being treated by Micro Arc Oxidation (MAO). The formed films were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The corrosion behavior of Gr.23 alloy in an artificial saliva environment at a temperature range of 293–323 K has been studied and assessed by means of electrochemical polarization and impedance spectroscopy techniques. Three cases are taken into consideration; bare Gr.23, Gr.23 coated by PE, and Gr.23 coated by PE after MAO treatment. The maxi