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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
Thu Jun 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Comparing Some of Robust the Non-Parametric Methods for Semi-Parametric Regression Models Estimation
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In this research, some robust non-parametric methods were used to estimate the semi-parametric regression model, and then  these methods were compared using the MSE comparison criterion, different sample sizes, levels of variance, pollution rates, and three different models were used. These methods are S-LLS S-Estimation -local smoothing, (M-LLS)M- Estimation -local smoothing, (S-NW) S-Estimation-NadaryaWatson Smoothing, and (M-NW) M-Estimation-Nadarya-Watson Smoothing.

The results in the first model proved that the (S-LLS) method was the best in the case of large sample sizes, and small sample sizes showed that the

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Crossref
Publication Date
Sun Apr 30 2023
Journal Name
Iraqi Journal Of Science
Estimation the Levels of Some Inflammatory Markers Among Young Iraqi Smokers and Non Smokers
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In this study it was found that a significant decrease in the level of leptin in young
Iraqi smokers (16+ 0.7ng/mL) compared to non smokers(24.2+ 4.5ng/mL) while, B2
microglobulin and CRPwas significantly increased in the smokers (1.2 + 0.3μg/mL),
(4.07+ 0.02mg/L) respectively, compared to non smokers (0.6 + 0.9μg/mL) ,( 2.88+
0.002mg/L) respectively, the presented data indicates the effect of smoking on these
immunological markers.

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Publication Date
Wed Mar 02 2022
Journal Name
Journal Of Educational And Psychological Researches
The Nature of Non-verbal Communication Skills Practiced by Educational Counselors in Individual Guidance
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This research is an attempt to achieve the following objectives: 1. identifying the nature of the non-verbal communication skills practiced by educational counselors in individual guidance. 2. Identifying the significant differences between non-verbal communication skills exercised by educational counselors from their point of view in regard to their gender (male-female). The researcher used a questionnaire as a tool prepared based on exploratory questions of educational counselors and literature. It has consisted of (26) items over four domains applied to a sample of (50) educational counselors (male and female) who have been chosen randomly from schools located in Baghdad Education Directorate Rusafa / 2. It was treated statistically u

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Publication Date
Thu Mar 31 2022
Journal Name
Journal Of The College Of Education For Women
News of Zubarah Family- Unionists in Nishapur and their Scientific Contributions in the two Centuries (4-6 AH/10-12 AD)
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This research is concerned with qualitatively studying the history of an ancient family, one of the most prominent noble, Alawite families, that assumed the position of the Student Union for the Alawite Supervision in the city of Nishapur in Khorasan during the centries (4-6 H./ 10-12 A.H.). Thus, the research aims to investgate the historical news, and the outstanding Zubarah figures who experience the supereme the religious, historical and scientific position in Khorasan generally and Nishapur particularily. It further aims at arriving at the true meaning of the name Zubarah, and to whom it was called, and the extent of this family’s affiliation to the noble Alawi House, and how they moved to live and settle in the cities of the East

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Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
Ecofriendly Control for Stored-Product Pest, Oryzaephilus surinamensis (Order: Coleoptera, Family: Silvanidae)
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Dates are considered one of the most important foods consumed in Arab countries. Dates are commonly infested with the sawtoothed grain beetle, Oryzaephilus surinamensis. Consequently, the date yield, quantity, and quality (economic value and seed viability) are negatively affected. This study was designed to investigate the effectiveness of air evacuation as eco-friendly and safe control method against adult O. surinamensis. Insects were obtained from the infested date purchased from a private store in sakaka city, Aljouf region, Saudi Arabia. Air evacuation (using a vacuum pump) and food deprivation were applied to O. surinamensis, and insect mortality was observed daily in comparison with the control group (a

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Scopus Crossref
Publication Date
Sun Apr 01 2012
Journal Name
Journal Of Educational And Psychological Researches
Family Atmosphere and Relationship to Academic Adjustment for Student at Baghdad University
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The research aimed: 1. Definition of family climate for the university students. 2. Definition of statistical significance of differences in family climate variable depending on the sex (males - females) and specialization (Scientific - humanity). 3. Definition of academic adjustment for university students. 4. Definition of correlation between climate and academic adjustment. The research sample formed of (300) male and female students by (150) male of scientific and humanitarian specialization and (150) female of scientific and humanitarian specialization randomly selected from the research community. To achieve the objectives of the research the researcher prepared a tool to measure family climate. And adopted the measure (Azzam 2010)

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Publication Date
Thu Jan 30 2014
Journal Name
Al-kindy College Medical Journal
Ventriculoperitonealshunt, Programmable or non-programmable
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Background:Hydrocephalus is dilatation of the ventricular system due to excessive production and/ or obstruction of cerebrospinal fluid (CSF) pathways. Different surgical procedure are used to treat this disease. Ventriculo peritoneal shunt is by far the most popular technique for CSF diversion..
Objective;To compare the programmable and non-programmable valves regarding the complications of both types
Methods:This study was conducted in the Neurosurgical hospital of Baghdad/Iraq over a period of 3 years from July 2008 to August 2011.
A special inclusion criteria has been tabulated for the selection of patients..
Results:.Fifty cases with hydrocephalus admitted and diagnosed by CT scan and treated by ventriculoperitoneal shun

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Publication Date
Tue Jan 01 2019
Wide-range tunable subwavelength band-stop filter for the far-infrared wavelengths based on single-layer graphene sheet
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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The importance of foreign direct investment in stimulating non-oil exports Of Iraq According to the Turkish experience
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Foreign trade is very important in global economies because of its impact on the sustainability of economic growth by stimulating economic activity, creating jobs and expanding production . On the other side , this policy is a major obstacle to many developing countries and the reason is due to the nature of the economies of those countries because they rely mostly on one or a few economic resources, which makes them rely mostly on exports to that resource while they import most of the needs of their  local market Which makes them in a spiral of underdevelopment ,  dependence and economic exposure, which requires them to break that cycle and the launch of economic development Perhaps one of the most important means to a

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Crossref
Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Study Effect of Lighting of Non – Regular on Statistical Properties for the Written Text on Whiteboard
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 Lighting is a very important element of treatment if the color contains many imaging system (digital cameras) and the unit of light and the light within these units are not strong , but usefel when the light is low , in different lighting intensities conditions image quality will not persist good enough and image may become dark or slightly exposed to light which leads to lower the details in image where we can not modify contrast or light ness to compensate thr decrease without losing the light and dark deatials . So we went in this research to study the variation colored texts written on the painting and lighting cases of non –regular ( a few) and different distances . As the diversity of these texts written on the board a

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