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Free Convection in an Inclined Concentric Annular Square Cavities Filled With Porous Medium and Heated By Non-Uniform Temperature
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A numerical study of the two-dimensional steady free convection flow in an inclined annulus between two concentric square cavities filled with a porous medium is presented in this paper for the case when the side outer walls are kept with differentially heated temperature while the horizontal outer walls and the inner walls are insulated. The heated wall is assumed to have spatial sinusoidal temperature variation about a constant mean value. The Darcy model is used and the fluid is assumed to be a standard Boussinesq fluid. For the Cartesian coordinate system, the governing equations which were used in stream function form are discretized by using the finite difference method with successive under – relaxation method (SUR) and are solved by Gauss-Siedel iterative method. The upwind scheme was used for the transport terms in the energy conservation equation. The results are presented to demonstrate the streamlines, the isotherms, and the Nusselt number depending on the Rayleigh number ranging from (Ra =10 to 1000), dimension ratio from (Dr = 0.15 to 0.45), and the inclination angle from (= 0o to 45o). Also the effects of the amplitude (=0 to 1) and the wave number (f =0 to 5) of the heated side wall temperature variation on the free convection are investigated. The results show the effect of previous parameters (Ra, Dr,, , and f) on the flow fields and temperature profiles. It also show that the average Nusselt number is a strong function of the Rayleigh number, inclination angle, dimension ratio, and temperature variation. The peak value of the average Nusselt number based on the hot wall temperature is observed to occur at dimension ratio of (0.15), inclination angle of (40.1°), amplitude and wave  number (1 & 0.75) for Rayleigh number of (1000).

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Publication Date
Tue Dec 13 2022
Journal Name
Frontiers In Chemistry
Numerical analysis of the energy-storage performance of a PCM-based triplex-tube containment system equipped with arc-shaped fins
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This study numerically intends to evaluate the effects of arc-shaped fins on the melting capability of a triplex-tube confinement system filled with phase-change materials (PCMs). In contrast to situations with no fins, where PCM exhibits relatively poor heat response, in this study, the thermal performance is modified using novel arc-shaped fins with various circular angles and orientations compared with traditional rectangular fins. Several inline and staggered layouts are also assessed to maximize the fin’s efficacy. The effect of the nearby natural convection is further investigated by adding a fin to the bottom of the heat-storage domain. Additionally, the Reynolds number and temperature of the heat-transfer fluid (HTF) are e

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Publication Date
Sun Dec 06 2009
Journal Name
Baghdad Science Journal
Study of properties of electrical conductivity of Tin dioxide thin films treated with Xenon impulse radiation used as Gas sensors
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During of Experimental result of this work , we found that the change of electrical conductivity proprieties of tin dioxide with the change of gas concentration at temperatures 260oC and 360oC after treatment by photons rays have similar character after treatment isothermally. We found that intensive short duration impulse annealing during the fractions of a second leads to crystallization of the films and to the high values of its gas sensitivity.

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Publication Date
Wed Aug 20 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Photogrammetric analysis of facial soft tissue profile of Iraqi adults sample with Class I normal occlusion: (A cross sectional study)
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Background: The purposes of this study were to determine the photogrammetric soft tissue facial profile measurements for Iraqi adults sample with class I normal occlusion using Standardized photographic techniques and to verify the existence of possible gender differences. Materials and methods: Eighty Iraqi adult subjects (40 males and 40 females) with an age ranged between 18-25 years having class I normal occlusion were chosen for this study. Each individual was subjected to clinical examination and digital standardized right side photographic records were taken in the natural head position which is mirror position which the patient looking straight into his eyes into the mirror mounted on the stand. The photographs were analyzed using A

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Virtual ( Electronic ) Reference Services In Academic Libraries: Virtual ( Electronic ) Reference Services In Academic Libraries
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Abstract
This paper deals with the concept of electronic reference services in academic
libraries , showing forms of communications , training needs for reference librarians
and the role of the librarian in the new technological environment.

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Publication Date
Sun Dec 20 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Auditing agricultural role in initiative for agricultural development: Applied research in agriculture Muthanna Directorate
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The study aims to indicate the role of the agricultural initiative in building agricultural development, mediated by activation of the role of internal and external audit on agricultural initiative projects, for the purpose of meeting the challenges of abuses on agricultural land and lack of water used in agriculture and proportions of high poverty, which led to the rural people of the migration to the city and leave agriculture and livestock, and that of the main conclusions reached by the researcher. When comparing the work of the external auditing agencies (the Federal Office of Financial Supervision) on the initiative of agricultural projects with internal audit services in the Directorate of Agriculture and branches of the Agricultu

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Publication Date
Mon Feb 01 2016
Journal Name
Al-academy
Calendar art activities in private schools Secondary School in Baghdad: سناء عبد الامير حسين
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The technical activities designed to highlight the creations of students by providing activities appropriate to their abilities and capabilities within and outside the school, which is a way for the development of learning and learner behavior aimed at directing guidance educationally and artistically.As a result of the efforts of modern educational activities, art has become part of the philosophy of the modern school and part of the modern curriculum. Because it is enough to configure the practices and habits of a satisfactory and acceptable, and is characterized by precision, order and beauty.Through the researcher with a survey of previous studies that dealt with art activities and found that all studies have been confined to a calen

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Publication Date
Sun Apr 17 2016
Journal Name
Al-academy
Expressionism in painting contemporary in Iraq Study features formalism: عبد الرزاق جبار رحيل الكناني
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In the present research is marked (expressive drawing in contemporary Iraq, the study of morphological features) eating expressive as the direction of modern art in the drawing for the period before and after World Wars I and II. And follow the tracks. And in research and investigation about the origins and sources and characteristics of expressionist painting at adult patrons and art gatherings, and the extent of their impact in the drawing for contemporary Iraqi sixties and seventies generation (generation of professors) and down to the younger generation in the eighties of the last century. Over the nearly two decades of history of fine movement in Iraq, a period specified in the search within the limits of temporal boundaries, and by

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Publication Date
Wed Oct 01 2014
Journal Name
Al–bahith Al–a'alami
Student Survey in Public Relations Services, Registration and Counseling, A Case Study of Petra University for the academic year 2013/2014.
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The research discusses the public relations services, registration, and academic advising at Petra University for the years 2013-2014. Using a field study and surveying Petra University students to be informed about the services and to cover the tiny details that have to do with public relations role in the university as a specialized department interested in serving public and gaining their trust in terms of what is legal and possible to build and enhance the university reputation. And gain mutual trust between the university and its publics.
The public relations is consi

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Publication Date
Tue Sep 15 2020
Journal Name
Al-academy
Forbidden Montage and the transition Technique in one-snapshot Movies 1917 Film- A model: محمد عبد الجبار كاظم-عذراء محمد حسن
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  Starting from the term (forbidden montage) initiated by the French critic (Andre Bazin) as a method of processing the movies that depend on (mise en scene) achieved by the action of the camera and its ability to photograph and employ the depth of the field, in addition to the possibility of free movement without interruption in the filming environment in order to avoid montage as much as possible (the montage that distorts focus and distracts attention and moves away from realism, which is the most important theoretical pillar of Bazin in photography). The pursuit was behind a cinema that depicts its topics in one integrated snapshot with all its details thus approximating reality without any interference of montage. Our study sta

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Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Use of lower squares and restricted boxes In the estimation of the first-order self-regression parameter AR (1) (simulation study)
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Use of lower squares and restricted boxes
In the estimation of the first-order self-regression parameter
AR (1) (simulation study)

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