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Numerical Investigation of Transient Heat Conduction through a Thermal Insulation of Temperature Dependant Thermal Properties
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The two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the interface between adjacent control volumes. A temperature dependent specific heat capacity proposed by a 4th Degree polynomial is fitted. A good agreement is obtained when the predicted results are compared with those obtained from the analytical solution.

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Publication Date
Thu Aug 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Economic contributions to small industrial projects (Selected international experiences with special reference to Iraq)
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Abstract:

Most of the studies on this subject, small industrial projects, by researchers and scholars in the economic field show the great and increasing importance of doing this kind of projects, the extent of which can be determined by the contribution of these projects to indicators and macroeconomic and sectorial variables. So this research aims to show the extent of the economic contribution of projects in selected international experiences and in the Iraqi economy. As international experiences have provided the opportunity for the progress and growth of small projects in their economies, which led to an increase in the contribution of these projects in the recruitment of economically active manpower, in added

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Publication Date
Mon Jan 23 2023
Journal Name
Arab Science Heritage Journal
العلاقات السياسية والعسكرية للإمارة العلوية في طبرستان مع الإمارة الطاهرية والصفارية والسامانية
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The stage of the establishment of the Alawite state in tabaristan was one of the most important stages in the history of the Shiite sect in Iran

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Publication Date
Tue Dec 16 2008
Journal Name
Journal Of Planner And Development
Housing finance and housing needs in Iraq with reference to some Arab experiences
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the financial resources represent a basic factor of production ;It is obvious that the housing sector needs the resources to finance the building operation to produce all the housing units. Finance is the cornerstone of any housing strategy , as its successes dependent on the success of the financing methods and the creation of charnels and effective methods for the provision of the required finances for both individuals and instantly concerned with the production of housing units. The kinds of financial institutions vary from one country to another according to the nature of the economic and financial system. The lending conditions also vary as well as the capital cost of the housing units needed The housing operations is concer

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Publication Date
Sat Jun 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Compared Some Estimators Ordinary Ridge Regression And Bayesian Ridge Regression With Practical Application
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Maulticollinearity is a problem that always occurs when two or more predictor variables are correlated with each other. consist of the breach of one basic assumptions of the ordinary least squares method with biased estimates results, There are several methods which are proposed to handle this problem including the  method To address a problem  and  method To address a problem , In this research a comparisons are employed between the biased   method and unbiased   method with Bayesian   using Gamma distribution  method  addition to Ordinary Least Square metho

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Budget Deficiency and Its Treatment Prospects and Policies with Reference to Iraq (2003-2012)
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Developed and underdevelopment countries, on equal terms, face the problem of budget deficiency. Budget deficiency means that the public expenditure surpasses the public revenues. This, on the international level, is one of the most serious economic problems with many direct effects on the national economy, and depends, basically, on its finance chosen method. Looking for a solution to this problem, for this reason and many other ones, has been highlighted in spite of the many attempts to reduce the role of the governmental expenditure. Budget deficiency can not be attributed to a single unique cause since it is complex phenomenons the causes of which are related to many factors contribute to its occurrence, some of which refer t

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Planner And Development
The "actor network theory" approach in dealing with landscapes in historical centers
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The historical center's landscape suffers from neglect, despite their importance and broad capabilities in enhancing the cultural value of the historical center, as landscape includes many heterogeneous human and non-human components, material and immaterial, natural and manufactured, also different historical layers, ancient, modern and contemporary. Due to the difference in these components and layers, it has become difficult for the designer to deal with it. Therefore, the research was directed by following a methodology of actor-network theory as it deals with such a complex system and concerned with an advanced method to connect the various components of considering landscape as a ground that can include various elements and deal wi

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Publication Date
Fri Sep 30 2011
Journal Name
Al-khwarizmi Engineering Journal
Studying the Effect of Addition Particles of Alumina (Al2O3) and Zirconia (ZrO2), on Some Mechanical Properties for Matrix Composites (Al-Si-Mg) Alloy
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This study is concerned with the effect of adding two kinds of ceramic materials on the mechanical properties of (Al-7%Si- 0.3%Mg) alloy, which are zirconia with particle size (20μm > P.S ≥ 0.1μm) and alumina with particle size (20μm > P.S ≥ 0.1μm) and adding them to the alloy with weight ratios (0.2, 0.4, 0.6, 0.8 and 1%). Stirring casting method has been used to make composite material by using vortex technique which is used to pull the particles to inside the melted metals and distributed them homogenously.

After that solution treatment was done to the samples at (520ºC) and artificial ageing at (170ºC) in different times, it has been noticed that the values of hardness is increased with the aging time of the o

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Publication Date
Wed Oct 05 2016
Journal Name
Al-academy
Relationship of psychological time with elements of movie's expression Example) movies, which their events takes, place in one day / as)
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This research deals with and which was entitled: relationship between psychological time and elements of filming expression (one-day event filmsas an example). It is about the relationship of psychological time (internal) with the elements of filming expression and how the time affected when using these elements in terms of its deceleration or acceleration. In particular, this research focus on elements that slow down time or stops it when using these elements. As one day time is short and heavy at the time of spectators in terms of the large number of film events which makes the viewer runs out of breath to understand the nature of those events and then identify the causes and consequences, as they occur in a short time (one day time) a

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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
Effects of rotation and MHD on the Nonlinear Peristaltic Flow of a Jeffery Fluid in an Asymmetric Channel through a Porous Medium
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In this paper, the effect of both rotation and magnetic field on peristaltic transport of Jeffery fluid through a porous medium in a channel are studied analytically and computed numerically. Mathematical modeling is carried out by utilizing long wavelength and low Reynolds number assumptions. Closed form expressions for the pressure gradient, pressure rise, stream function, velocity and shear stress on the channel walls have been computed numerically. Effects of Hartman number, time mean flow, wave amplitude, porosity and rotation on the pressure gradient, pressure rise, stream function, velocity and shear stress are discussed in detail and shown graphically. The results indicate that the effect of Hartman number, time mean flow, wave a

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Publication Date
Mon Dec 11 2017
Journal Name
Al-khwarizmi Engineering Journal
Simulation Model of Wind Turbine Power Control System with Fuzzy Regulation by Mamdani and Larsen Algorithms
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Abstract 

     The aim of this work is to create a power control system for wind turbines based on fuzzy logic. Three power control loop was considered including: changing the pitch angle of  the blade, changing the length of the blade and turning the nacelle. The stochastic law was given for changes and instant inaccurate assessment of wind conditions changes. Two different algorithms were used for fuzzy inference in the control loop, the Mamdani and Larsen algorithms. These two different algorithms are materialized and developed in this study in Matlab-Fuzzy logic toolbox which has been practically implemented using necessary intelligent control system in electrical engineerin

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