In this paper, the problem of developing turbulent flow in rectangular duct is investigated by obtaining numerical results of the velocity profiles in duct by using large eddy simulation model in two dimensions with different Reynolds numbers, filter equations and mesh sizes. Reynolds numbers range from (11,000) to (110,000) for velocities (1 m/sec) to (50 m/sec) with (56×56), (76×76) and (96×96) mesh sizes with different filter equations. The numerical results of the large eddy simulation model are compared with k-ε model and analytic velocity distribution and validated with experimental data of other researcher. The large eddy simulation model has a good agreement with experimental data for high Reynolds number with the first, second and third mesh sizes and the agreement increase near the wall of the duct. The percentage error for the large eddy simulation model with experimental data of the (56×56) mesh size is less than 18 % and for the (76×76) mesh size is also less than 17% and for the (96×96) mesh size is less than 16 %. The large eddy simulation model show high stability and do not need extra differential equation like the k-ε model and a great saving in time and computer memory was achieved.
Abstract: In accordance with contemporary Western thinking, power is an organized force with a high ability to achieve stability and social security because it possesses tools based on rational organization, which helps it to control the behavior of the individual and society and prevent them from practicing the processes of exclusion and discrimination against others in pursuit of their interests and needs. Vision The philosophers and thinkers of the theory of social contract can consolidate it, which changed the form and nature of power from the traditional heritage to the constructionWhich has contributed to the development and development of civil society - Western political, and despite the success of this experiment, especially aft
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Background: Otitis media with effusion is characterized by accumulation of fluid in the middle ear in absence of acute inflammation and it is the most common cause of acquired hearing loss in children, and may negatively affect language development failure of medical treatment of middle ear effusion frequently require myringotomy and tympanostomy tube insertion.
Objectives: To determine tympanostomy tube complications of tube in children with chronic otitis media with effusion who were treated with Shah Grommet tube insertion.
Methods: The Medical records of 162 ears of 87 children (52 male and 35 female) were reviewed respectively, the patients ages wer
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اليورانيوم المنضب واستخدامه امريكياً في العراق
It is obvious that the constitutional- political structures which has been emerged in Iraq after the occupation in 2003 frame worked by many sectarian, ethnic, tribal and political orientations, pushing forewords to escalating the contradictions between social- political powers, however, these changes unfortunately result not just destroy and taking apart the political regime and his authority, but the state and his institutions as well, although, did not stamped as wise and rational change for better future to new Iraq and its political, civil and military institutions. Finally, as quick as Iraq start to bisects to sectarian, ethnic and national components according to the new political – social components of Iraq. Indeed, what is req
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This research tackles the play of Synge "Rider to the Sea" to find out whether the theories of Leech (1983) and Brown and Levinson (1987) can be applied or not to this study. The model of Leech (1983) consists of seven principles and for Brown and Levinson (1987),it consists of two principles of politeness where one of them is positive and the other is negative politeness. It is hypothesed that: 1. There is a relation between the two theories. 2. Synge deals with these theories in such a way to depict his characters. 3. It is also hypothesed that every character deals with these principles in such a way to show the events of the play. The study concludes that there is a relation between the two theories in depicting the characters then it s
... Show MoreThe loss of dental hard tissue as a result of odontoclastic activity is known as root resorption. It is unwanted and pathological in permanent teeth. Root resorption may happen within the root canal called internal root resorption or on the outer surface of the root called external root resorption. Regardless of where it occurs, root resorption is irreparable, can cause pain for the patient, necessitates treatment, and in some circumstances, resulting in the early loss of the affected tooth. It might be challenging to precisely diagnose and treat root resorption. There is limited information within literatures on root resorption therefore this review aims to understand the radiological and clinical characteristics of r
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Background: Squamous cell carcinoma of the oral
cavity (OSCC) is a highly invasive neoplasm. Many
MMPs play role in human cancer invasion and
metastases.
Aim: Estimating The MMp-7 expression level in
HPV-16 positive and HPV-16 negative OSCC
paraffin embedded sections.
Method: Biopsies from thirty three patients with oral
squamous cell carcinoma (OSCC) were obtained and
investigated for the presence of HPV-16 RNA with
the application of ISH and the MMP-7 expression
level using IHC .
Results: Expression level of MMP-7 found to be high
in OSCC sections 29 (87.8%) cases with no
significant difference in its expression level between
HPV-16 positive and HPV-16 negative OSCC cases
p= 1.00.
Conc
Zainab M. Al-Bahrani Department of Oral Diagnosis, College of Dentistry, University of Baghdad, Baghdad, Iraq.Corresponding author: Zainab M. Al-Bahra...
Background: Febrile convulsions are the most frequent type of seizures in children under 6 years of age. Significant percentage of these children will later suffer from recurrence of febrile convulsion.Objectives: To identify the main risk factors for recurrent febrile convulsions in children.Methods: we carried out a case control study involving 89 children those who experienced first attack of febrile convulsions and 92 children with recurrent attack of febrile convulsions. The study was conducted in Central Children Teaching Hospital, Baghdad during the period 2006- 2007. Results: Compared to children with first attack of febrile convulsion, children with recurrent seizures were younger at onset (4- 12m) (67% vs. 44%), mainly male (70
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