Natural convection in a trapezoidal enclosure with partial heating from below and symmetrical cooling from the sides has been investigated numerically. The heating is simulated by a centrally located heat source on the bottom wall, and four different values of the dimensionless heat source length, 1/5, 2/5, 3/5, 4/5 are considered. The laminar flow field is analyzed numerically by solving the steady, two-dimensional incompressible Navier-Stokes and energy equations. The Cartesian velocity components and pressure on a collocated (non-staggered) grid are used as dependent variables in the momentum equations discretized by finite volume method; body fitted coordinates are used to represent the trapezoidal enclosure, and grid generation technique based on elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the velocity field to satisfy the conservation of mass. The range of Rayleigh number is (103≤ Ra ≤105) and Prandtl number is 0.7. The results show that the average Nusselt number increases with the increases of the source length.
المستخلص: تناول البحث الحالي " علاقة العوامل الحرجة لنقل المعرفة في فرص النجاح الاستراتيجي " إذ يحظى موضوعيّ نقل المعرفة والنجاح الاستراتيجي باهتمام متزايد لكونهما من الموضوعات المهمة والمعاصرة، والتي لها تأثير كبير على وجود المنظمات ومستقبلها. ويهدف البحث الى الوقوف على العوامل الحرجة لنقل المعرفة في بيئة التعليم الأهلي العالي والتي تُمكن ( الكليات الأهلية المبحوثة ) من تحقيق نجاحها الاستراتيجي وقد سعى الب
... Show MoreThe research aims at identifying the relationship between the process of managing intellectual knowledge and its impact on the development and sustainability of the Iraqi insurance sector by conducting an analysis of the types of intellectual knowledge owned by Iraqi insurance companies and the amount of revenues generated from each type of services provided to customers. &
... Show MoreThe current research discusses “The impact of the critical factors for the transfer of knowledge on opportunities and strategic success ", the attention have been increased on knowledge transfer and strategic success subjects because on being one of the important and contemporary issues, which have a significant impact on the existence of organizations and its future. The research aims to identify the critical factors for knowledge transfer in private high education environment which enables (the college community surveyed) to achieve strategic success, also the research sought to answer questions related to research problem by testing a number of major and minor hypothes in impact, in order to test the hypotheses I used a fiel
... Show MoreThe study aims at identifying the reasons of weakness in the reading and writing of the primary schools' pupils at Baghdad governate in Iraq from the educational supervisors' point of view.
The community research contained the educational supervisors of Baghdad governate for the academic year 2011\2012, consisting of a total number of (344), of which (175) were males and (169) were females, where as the sample of the research consisted of (100) educational supervisors.
The researcher made up a questionnaire which is consisted of (78) items, distributed over different fields ( the curriculum and the book, methods of teaching, educational technology
... Show MoreAbstract
The Verbal Violence that is directed towards sons is considered one of
the dehavioural problems that have negative reflections on the personality
of the individual . the increase in the frequency and intensity of that
behavior in the daily life may lead to psychological and behavioural
disturbances, and such behaviourhas to be stooped in an early time before it
leave negative affects on the personality of the teenager which will not be
cured or removed easily .
The family that is represented by the parents has a prominent effect In the
shaping of the teenager's personality , hence forth the normal teenage is
a reflection of a stable family life , relatively empty of disturbances and
unbalanc
This research deals with the relationship between television advertising and buying random cosmetics, where we find that TV ads influence on the purchasing behavior of women, has conducted research in the field on a sample of women in the University of Baghdad, was a random sample taken from 150 different women in the age and social levels educational and cultural students and employees and teachers in order to sample representative be for the research community, and designed a questionnaire for this purpose form as a tool to collect data and information search and analyzed they answered the sample surveyed using a statistical program (spss) to extract percentages And correlation coefficients and testing square Kay , The study found Of w
... Show Morethis study examined the various incidents of heritage and documentary dimension in relation with the contemporary history of Baghdad and the presence of religious minorities and ethnicities. The Baha'i came to Iraq in the late century and the list of religious minorities is still not recognized. In this research study
تم التحري عن انتاج انزيم الكايتنيز من خميرة Saccharomyces cerevisiae حيث زرعت هذه الخميره في وسط سائل يحتوي على الكايتين ومواد نتروجينية مختلفة . اجريت غربلة لسلالات الخميرة المستعملة لتعين السلالة الاعلى انتاجا للانزيم . بينت النتائج ان السلالة S2 اعطت اعلى فعالية نوعية بلغت 3.5 وحدة /ملغم بروتين .
Targeted research to find control procedures to reduce contamination of drinking water and whether the public water systems monitor the channels properly and it is free from all pollution to try to reduce the phenomenon of environmental pollution of drinking water and therefore its impact on improving the health status and economic development. Thus, the practical side took the proposed framework to reduce the contamination of drinking water in the province of Baghdad, and the role of environmental control to reduce this pollution and to eliminate the problem of providing drinking water in the countr.
This paper describes a microcontroller-based function generator system. By the function generator sine wave, square wave, quasi-square wave, saw-tooth and triangular waveforms are generated over a wide frequency range according to user requirements. By utilizing processing capabilities of the microcontroller the hardware is minimized exceedingly. The output waveform shapes are digitally-controlled to achieve the required wave shape. The single chip microcomputer of waveform generation equipment offers the possibility of improvements in manufacture reliability, maintenance and servicing and increased control flexibility. The system is built and tested. The results of test were satisfactory and appreciated by test engineers at different ce
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