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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 Sep 30 2019
Journal Name
College Of Islamic Sciences
The provisions of the monkey in Islamic jurisprudence
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The provisions of the monkey in Islamic jurisprudence

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Publication Date
Wed Feb 12 2025
Journal Name
Sciences Journal Of Physical Education
Perceived organizational support and its relationship to the cognitive competence of the Iraqi National Olympic Committee from the point of view of members of the Olympic sports federations in Iraq
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Publication Date
Wed Oct 02 2024
Journal Name
International Development Planning Review
COMPARISON OF THE PERFORMANCE OF THE FOREHANDKICK (STRAIGHT AND ACCOMPANIED BY FORWARD ROTATION) IN TERMS OF ACCURACY AND SPEED AMONG THE PLAYERS OF THE NATIONAL TEAM (ADVANCED CATEGORY) IN TENNIS
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Publication Date
Wed Oct 02 2024
Journal Name
International Development Planning Review
COMPARISON OF THE PERFORMANCE OF THE FOREHANDKICK (STRAIGHT AND ACCOMPANIED BY FORWARD ROTATION) IN TERMS OF ACCURACY AND SPEED AMONG THE PLAYERS OF THE NATIONAL TEAM (ADVANCED CATEGORY) IN TENNIS
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Publication Date
Fri Oct 02 2020
Journal Name
International Development Planning Review
COMPARISON OF THE PERFORMANCE OF THE FOREHANDKICK (STRAIGHT AND ACCOMPANIED BY FORWARD ROTATION) IN TERMS OF ACCURACY AND SPEED AMONG THE PLAYERS OF THE NATIONAL TEAM (ADVANCED CATEGORY) IN TENNIS
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Publication Date
Wed Oct 02 2024
Journal Name
International Development Planning Review
COMPARISON OF THE PERFORMANCE OF THE FOREHANDKICK (STRAIGHT AND ACCOMPANIED BY FORWARD ROTATION) IN TERMS OF ACCURACY AND SPEED AMONG THE PLAYERS OF THE NATIONAL TEAM (ADVANCED CATEGORY) IN TENNIS
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Publication Date
Mon Jan 29 2024
Journal Name
Eximia
The cognitive and educational importance of the academic teacher for developing the applied skills of third-stage female students in the subject of teaching methods from their point of view
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The research aimed to prepare a measure of the importance of enlightenment, academic education, and applied skills for third-stage female students, including teaching methods from their point of view/College of Education and Sports Sciences/University of Baghdad/Al-Jadriyah. The researchers used descriptive description in the comprehensive research procedures, an appropriate methodology in achieving the research objectives, sufficient for interpretations, how important is the academic teacher’s knowledge of teaching methods for student learning, what are the roles that the learners have acquired from the academic teacher. The scale of importance and horror consists of 15 items. The research population includes female students of t

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Publication Date
Sun May 15 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Population growth and the culture of consumption A field study in the city of Arbil.: Population growth and the culture of consumption A field study in the city of Arbil.
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research objectives to:
1. identify the social, economic and cultural factors affecting consumption.
2. detect the consumption culture among the population in the city of Erbil.
3. Identify the GATT consumer protection and rights.
The most important results:
1. that there is variation in the answers of respondents about keep up with modernity in the basic consumption (necessary), it swallowed the proportion of yes answers about keep up with modernity in food consumption (72%), and is an indication of growing consumer awareness of the individual in the side of nutrition. The clothing on the side of the proportion of yes answers amounted to (85%), in the health field note that the percentage of yes answers (83%), who are abr

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Publication Date
Tue Nov 24 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
The Impact of External Environment Factors on the Quality of Educational Services (An Empirical Study): The Impact of External Environment Factors on the Quality of Educational Services (An Empirical Study)
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This research aims to identify the role of external environment factors on the quality of educational services, from the academic point of view, where the distribution of a questionnaire to a random sample of (100) university professors, and then analyzing a model, and test the validity of this model using structural modeling (SEM) (Structural Equation Modeling).
And then test the relationships between variables using the software of Statistical Package for Social Sciences (SPSS V.18), the research found a number of conclusions, the most important conclusion is: the external environment factors has significant impact on the quality of educational services.

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Publication Date
Thu Dec 20 2018
Journal Name
مجلة العلوم الاجتماعية والتربوية (ريس)
The acquisition of the concepts of nanotechnology by the students of chemistry in the college of Education for pure Sciences/ibn Al-Haytham and it`s relation to their technological
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One of the scientific education aims, preparing a student able to keep up with the scientific developments and innovations around him and make him contribute, adapt, investment and continue development. The concepts of nanotechnology from scientific innovation open up an important area of thinking and intervention in the field of chemistry applications in daily life, the technological changes lead to social, political and economic changes which result that the students to have the knowledge, understanding, awareness, appreciation and sense in applications of modern technology for their use optimally, in order to cope with these scientific and technological changes. The research aims at finding out the correlation between the acquisi

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