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The Convective Instability of BEK Family of Non-Newtonian Rotating Boundary-Layer Flows
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The BEK family of flows have many important practical applications such as centrifugal pumps, steam turbines, turbo-machinery and rotor-stator devices. The Bödewadt, Ekman and von Kármán flows are particular cases within this family. The convective instability of the BEK family of rotating boundary-layer flows has been considered for generalised Newtonian fluids, power-law and Carreau fluids. A linear stability analysis is conducted using a Chebyshev collocation method in order to investigate the effect of shear-thinning and shear-thickening fluids for generalised Newtonian fluids on the convective Type I (inviscid crossflow) and Type II (viscous streamline curvature) modes of instability. The results reveal that shear-thinning power-law fluids have a universal stabilising effect across the entire BEK family of flows. However, the convective instability characteristics for the shear-thinning and shear-thickening Carreau fluids are affected by the value of the relaxation parameter k. The results reveal that Shear-thinning Carreau fluids have a small destabilising effect, while shear -thickening fluids have a slight stabilising effect on the Type I and Type II mode for the BEK family of flows when k =100. On the other hand, shear-thinning and shear-thickening Carreau fluids are found to have stabilising and destabilising effect, respectively for optimal relaxation value ko. The results are presented in terms of neutral curves and growth rates. Furthermore, an energy analysis is presented to gain insight into the underlying physical mechanisms behind the stabilising effects of generalized Newtonian fluids. In conclusion, the use of shear-thinning power-law and Carreau fluids with optimal value ko can be recommended to reduce skin-friction drag in enclosed rotor-stator devices for the entire BEK family of flows.

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Publication Date
Mon Jul 09 2018
Journal Name
اتحاد الاحصائيين العربوقائع المؤتمر الدولي العلمي السادس لاتحاد الاحصائيين العرب
The Use of Markov Chain to reveal the reality of non- oil econ0miv indicators in Iraq
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The research mainly seeks to predict the amounts of non- oil Iraqi exports which concludes ) Food & Animals , Raw materials and non- tanned Leather and fur , Mineral fuels and Lubricating Oil , Chemical substances and amounts , Manufactured goods , Electrical and non - electrical machines , Supplies and Total non- Oil exports ) by using Markov Chain as one of Statistical approach to forecasting in future . In this search We estimate the transliteration probabilities matrix according to Maximum Likelihood on a data collected from central organization for Statistics and information technology represents an index numbers of non- Oil exports amount in Iraq from 2004 to 2015 depending on 2007 as a basic year . Results shown that trend of index

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Influence of Rotation and Inclined Magnetic Field with Mixed Convective Heat and Mass Transfer in an Inclined Symmetric Channel on Peristaltic Flow with Slip Conditions
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     In paper, we study the impact of the rotationn inclined magnetic felid and inclined symmetric channel with slip condition on peristaltic transport using incompressible non-Newtonian fluid. Slip conditions for the concentration and heat transfer are considered. We use the conditions on the fluid, namely infinite wavelength and low - Reynolds number to simplify the governed equations that described - motion flow, energy and concentration. These equations ofroblem are solved by the perturbation technique and restricted the number of Bingham to a small value to find the final expression of the stream function. The Bingham number, Brinkman number, Soret number, Dufour number, temperature, Hartman number and other parameters are teste

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Publication Date
Fri Jan 01 2021
Journal Name
Ieee Access
Fast Shot Boundary Detection Based on Separable Moments and Support Vector Machine
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Publication Date
Mon Apr 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Solving Linear Boundary Value Problem Using Shooting Continuous Explicit Runge-Kutta Method
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  In this paper we shall generalize fifth explicit Runge-Kutta Feldberg(ERKF(5)) and Continuous explicit Runge-Kutta (CERK) method using shooting method to solve second order boundary value problem  which can be reduced to order one.These methods we shall call them as shooting Continuous Explicit Runge-Kutta method, the results are computed using matlab program.

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Publication Date
Mon Sep 30 2024
Journal Name
Joiv : International Journal On Informatics Visualization
Evaluation of the Performance of Kernel Non-parametric Regression and Ordinary Least Squares Regression
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Researchers need to understand the differences between parametric and nonparametric regression models and how they work with available information about the relationship between response and explanatory variables and the distribution of random errors. This paper proposes a new nonparametric regression function for the kernel and employs it with the Nadaraya-Watson kernel estimator method and the Gaussian kernel function. The proposed kernel function (AMS) is then compared to the Gaussian kernel and the traditional parametric method, the ordinary least squares method (OLS). The objective of this study is to examine the effectiveness of nonparametric regression and identify the best-performing model when employing the Nadaraya-Watson

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Publication Date
Thu Jul 01 2010
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
DISTRIBUTION OF HADJELIA TRUNCATA CREPLIN, 1825 (HABRONEMATIDAE,SPIRURIDEA) AMONG MEMBERS OF THE AVIAN FAMILY COLUMBIDAE IN AL-DIWANIYA PROVINCE, CENTRAL IRAQ
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A total of 28 birds were examined to investigate about the distribution of the nematode Hadjelia truncata among some members of the avian family Columbidae in Al-Diwaniya Province, Central Iraq. The percentages of the infection rate with this nematode were 27.27, 37.5, 14.28 and 0 in Columba livia, C. palumbis, Streptopelia decaocto, and S. turtur respectively. Reporting Hadjelia truncata from Streptopelia decaocto constitutes a new host record.

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Publication Date
Thu May 28 2020
Journal Name
Iraqi Journal Of Science
Morphological and Molecular Identification of Three Genera of the Family Heptageniidae (Ephemeroptera) from Ava Sheen Branch/ Greater Zab Tributary, North of Iraq
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The aquatic Heptageniidae family of Ava-sheen branch (Greater Zab Tributary) in Duhok Governorate/ Iraq was studied. Samples were collected using Surber stream sampler to study their diagnostic morphological characteristics and molecular phylogenetic profile using a nuclear gene 16s ribosomal RNA. The morphological and molecular identification supported that the three species, Epeorus longimanus, Heptagenia elegantula and Ephemerella cornutus belong to Heptageniidae family, while the molecular results also confirmed the monophyletic origin of these three genera.

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Publication Date
Tue Sep 01 2015
Journal Name
Nano Science And Nano Technology
Preparation CuInSe2 (CIS) by arrested precipitation method as alight absorption layer of photovoltaic solar-cells
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The CuInSe2 (CIS) nanocrystals are synthesized by arrested precipitation from molecular precursors are added to a hot solvent with organic cap- ping ligands to control nanocrystal formation and growth. CIS thin films deposited onto glass substrate by spray - coating, then selenized in Ar- atmosphere to form CIS thin films. PVs were made with power conversion efficiencies of 0.631% as -deposited and 0.846% after selenization, for Mo coated, under AM 1.5 illumination. X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) analysis it is evident that CIS have the chalcopyrite structure as the major phase with a preferred orientation along (112) direction and the atomic ratio of Cu : In : Se in the nanocrystals is nearly 1 : 1 : 2

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Publication Date
Thu Jan 23 2020
Journal Name
Acoustics Australia
Absorption Coefficient of a Double-Layer Inhomogeneous Micro-perforated Panel Backed with Multiple Cavity Depths
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Double-layer micro-perforated panels (MPPs) have been studied extensively as sound absorption systems to increase the absorption performance of single-layer MPPs. However, existing proposed models indicate that there is still room for improvement regarding the frequency bands of absorption for the double-layer MPP. This study presents a double-layer MPP formed with two single MPPs with inhomogeneous perforation backed by multiple cavities of varying depths. The theoretical formulation is developed using the electrical equivalent circuit method to calculate the absorption coefficient under a normal incident sound. The simulation results show that the proposed model can produce absorption coefficient with wider absorption bandwidth compared w

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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
The Role of the Family in investment Effect of the Mates in Evaluating the Childs Acceptance (2-5 years) of rich foods and inhancemenl rein for cement of the social love concepts: The Role of the Family in investment Effect of the Mates in Evaluating the Childs Acceptance (2-5 years) of rich foods and inhancemenl rein for cement of the social love concepts
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Abstract:
The aim of the present research is to evaluate the child’s nutritional
method (2-5 years old) which is based on his resistance of the food highly rich
with nutritional elements and his acceptance of the food of a low nutritional
value in addition to his having forbidden food with other mates and making
use of all mates when having food, in establishing the sound social values and
affection since child hood. The required statistical equation have been used
by the researcher namely (Z test).
The sample of the present study consists of (26) children who were selected
intentionally and randomly from the kindergartens of Al-Bayaa region and the
college of Education for women. The questionnaires were d

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