The steady state laminar mixed convection and radiation through inclined rectangular duct with an interior circular tube is investigated numerically for a thermally and hydrodynamicaly fully developed flow. The two heat transfer mechanisms of convection and radiation are treated independently and simultaneously. The governing equations which used are continuity, momentum and energy equations. These equations are normalized and solved using the Vorticity-Stream function and the Body Fitted Coordinates (B.F.C) methods. The finite difference approach with the Line Successive Over-Relaxation (LSOR) method is used to obtain all the computational results. The (B.F.C) method is used to generate the grid of the problem. A computer program (Fortran 90) is built to calculate the steady state Nusselt number (Nu) for Aspect Ratio AR (0.55-1) and Geometry Ratio GR (0.1-0.9). The fluid Prandtl number is 0.7, Rayleigh number Ra = 400, Reynolds number Re = 100, Optical Thickness (0 ≤ t ≤ 10), Conduction- Radiation parameter (0 ≤ N ≤ 100) and Inclination angle λ = 45. For the range of parameters considered, results show that radiation enhance heat transfer. It is also indicated in the results that heat transfer from the surface of the circle exceeds that of the rectangular duct. Generally, Nu is increased with increasing GR, t and N but it decreased with AR increase. When the radiation effect added to the heat transfer mechanism, the heat transfer rate increased. This effect increased with increasing in GR and decreasing with AR. The increasing in radiation properties lead to increase the radiation effect. Tecplot 7 program was used to plot the curves which cleared these relations and isotherms and streamlines which illustrate the behavior of air through the channel and its variation with other parameters. A correlation equation is concluded to describe the radiation effect. Comparison of the results with the previous work shows a good agreement.
For the first time in Iraq, the crustacean Ergasilus ogawai Kabata,
1992 was recorded from the gills of Silurus triostegus, Mastacembelus mastacembelus, Mystus pelusius and Acanthopagrus latus out of 12 fish species caught from Garmat Ali river north of Basrah city during the period from September 1999 till August 2000. The percentage incidence of infestations of these four fish species were 98.9%, 100%,
49.6% and 71.4% while the intensity of infestations were 417, 81.8,
3.4 and 2, respectively. No significant differences in infestations of
male and female hosts with this crustacean were detected.
This research was conducted in order to monitor and measure the dimensions of media policy in satellite channels directed from the point of view of the communicator, and this research is classified among the descriptive studies, as the researcher used the survey method to answer the questions that were formulated in light of the research problem represented by the main question: What are the dimensions of media policy in Directed satellite channels? .
To achieve the objectives of the study, the researcher used the following tools:
The questionnaire, in order to survey the attitudes of communicators about the extent to which the media policy during crises reflects on their professional standards. The research community is represente
(1)
This research is concerned with studying the representations of the event in the drawings of the ancient civilizations of the world, and the research consists of two axes, the axis of the theoretical framework, which included (the research problem, its aim, its limits, and the definition of its terminology).
The research aims to reveal how the event pattern was formulated by the artist on the surface of his visual achievement, and the limits of the search were spatial in the ancient civilizations of Iraq, Egypt, Greece and Rome, but the limits of the temporal research could not be determined because they were before birth, and objectively:
representations of the event in the civilizations of the ancient world This axis also in
The research aims to know the impact of workers values on their performance which is reflected on increasing productivity and improving its quality as well as the organization's progress and success. Application of this research took place in the General Company Of Electrical Industries; it contained four main pillars; the first involved research methodology، regarding the problem، importance، aim، basic theory، and method of data collection، the second is dedicated to the theoretical framework related to the research basic variables (values and workgroups) the third is assigned to analyze the actual data by using number of statistical methods، such as mathematical medium and standard deviation and also spearman rank
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This study presents the determination of the paleostress magnitudes and orientation of Bekhme Structure in Shaqlawa area, northeastern Iraq. Paleostress analysis of slip-fault measurements is performed using Right dihedral, Lisle diagram, and Mohr Circles methods. Depending on Mohr Circles, Bott law, and vertical thickness, the magnitudes of the paleostress at the time of the tectonic activity were determined. Firstly, Georient Software was used to estimate the orientation of the paleostresses (σ1, σ2, and σ3). Secondly, using the rupture –friction law, taking into account the depth of the overburden and the vertical stress (σv),the magnitudes of the paleostresses were calculated (σ1=4500 bars, σ2=1900 bars and σ3=700 bars). &nb
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The importance of the accounting profession in creating data and accounting information for economic resources and their sources and changes therein , through the effectiveness of this information and the degree of suitability and providing accurate and timely manner and in a form that makes it able to rationalize decisions and performance reporting , and there are several elements and behaviors control how the effectiveness of these reports and these behaviors work ethic that govern the work of management accountant when preparing performance reports , which are the ethics of the work of professional control principles and rules of accounting , legal, such as objectivity and reliability , neutrality and timeliness that must be a
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The parasite E.histolytica was first isolated from a stool sample, and then cultivated and maintained in vitro using Locke-egg medium (LEM) and Liver infusion agar medium (LIAM) . Then, the effect of some types of erythrocytes (human and sheep), on the growth and activity of the parasite in the two culture media was investigated. The parasite was able to ingest and lysis erythrocytes of human and sheep that were supplemented to the culture media and such manipulation was able to augment the reproduction rate of the cultivated E. histolytica, however, such consequence was media- and concentration-dependent. The reproduction rate was significantly increased (66.0, 57.5 and 58.6%, respectively) in LEM medium containing human erythrocytes ty
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Abstract
The multiple linear regression model of the important regression models used in the analysis for different fields of science Such as business, economics, medicine and social sciences high in data has undesirable effects on analysis results . The multicollinearity is a major problem in multiple linear regression. In its simplest state, it leads to the departure of the model parameter that is capable of its scientific properties, Also there is an important problem in regression analysis is the presence of high leverage points in the data have undesirable effects on the results of the analysis , In this research , we present some of
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The construction of development is required to develop various economic sectors with the necessity to meet the various requirement of both individuals and institutions , or through the import process , which must be commensurate with the needs of the market and the economy and development. But in fact , we find that the process of import in Iraq after 2003 took a turn dangerous excesses on limits of philosophy and objectives of the import , which is reflected at the level of national production as well as the policy of dumping and given and the lack of matching a lot of goods and materials imported for Standards and Measures of quality and stands behind it causes many of them exposure to the market and weak sectors with an overlap betwee
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Abstract
The research the impact of the application of some of the production system tools in the specified time, which can be adapted in the service sectors (banking sector) over the improvement and increase the quality of banking services, and highlights the research problem in the low quality of banking services provided to customers because of the reliance on traditional banking systems in the provision of services Because of the lack keep pace with global developments in the banking industry, and the goal of research is to clarify the applicability of the production system in the time specified in the service sector and th
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