Abstract  

All central air conditioning systems contain piping system with various components, sizes, material, and layouts. If such systems in operating mode, the flow in piping system and its component such as valves can produce severe vibration due to some flow phenomenon’s. In this research, experimental measurements and numerical simulation are used to study the flow-induced vibration in valves. Computational fluid dynamics (CFD) concepts are included with one-way and two-way fluid-structure interaction concepts by using finite element software Package (ANSYS 14.57). Detection analysis is performed on flow characteristics under operation conditions and relations with structural vibration. Most of

A computerized investigation has been carried out on the design of six electrodes electrostatic lenses used in electron gun application. The Finite-Element Method (FEM) was used in the solution of Laplace equation for determine the axial potential distribution. The electron trajectory under zero magnification condition. The optical properties, spherical and chromatic aberrations, the object and image focal length and object and image position are calculated. A very good futures for the electron gun with these lenses have been computed where are a beam current of 8.7*10-7A can be supplied using cathode tip of radius 10nm.

Feminism is a diverse set of social theories, political movements and ethos driven by women's causes. Feminists and feminists agree that the ultimate goal is to eliminate the forms of gender-related oppression It should be noted that feminism originated at the beginning as an emancipation movement aimed only at lifting the injustice and suffering of European women, but over time evolved and crystallized to form an independent thought in itself swimming against all the universals known to humanity in the relationship between male and female nature This study posits a hypothesis that the feminist movement is characterized by multiple and varied trends, different in its analyzes of the causes of women's oppression, but all agreed on the need t

الاتحاد المغاربي ومشكلة الصحراء الغربية

The Estimation Of The Reliability Function Depends On The Accuracy Of The Data Used To Estimate The Parameters Of The Probability distribution, and Because Some Data Suffer from a Skew in their Data to Estimate the Parameters and Calculate the Reliability Function in light of the Presence of Some Skew in the Data, there must be a Distribution that has flexibility in dealing with that Data. As in the data of Diyala Company for Electrical Industries, as it was observed that there was a positive twisting in the data collected from the Power and Machinery Department, which required distribution that deals with those data and searches for methods that accommodate this problem and lead to accurate estimates of the reliability function,

The research tacklets the role of risks arising from the excessive use of derivative contracts for trading in financial crises, including the recent global financial crisis in (2008) which is known the mortgage crisis.

   In order to prove the hypothesis of the research, the risk index of derivative contracts has been chosed as expressed in the measure of (value at risk) to be the main field for testing the hypothesis of research. The duration of the contract  has been also chased  for (15) years between the years (2001- 2015), the period preceding the global financial crisis, while the second represents the period of time that followed. The research reached a number of conclusions, bu

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

Increased the need to promote the profession of auditing, and improving the performance of the audit process, which comes through the effective implementation of its tasks, where the auditor collects the necessary data about the nature of client activity, and any other information it deems necessary to carry out the planning and development of the strategy for how to determine the procedures for implementing the audit process and the scope and timing for evidence clues in order to form an opinion technician neutral about the fairness of the financial statements, as required by the standards of the field work of the planning and supervision of the internal control and evidence to prove, but the failure of the auditor whether in th