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Aeroelastic response and limit cycle oscillations for wing-flap-tab section with freeplay in tab
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A linear and nonlinear theoretical and experimental aeroelastic investigation of a wing-flap-tab typical section model undergoing two-dimensional incompressible airflow is described. The linear flutter velocity (LFV) and frequency are predicted using linear analysis. Then a freeplay structural nonlinearity is considered in the tab. The structural equations of motion have been coupled with Theodorsen aerodynamic theory to produce the theoretical aeroelastic model which is analyzed by a state space method to predict the LFV and flutter frequency. Linear piecewise function has been used to introduce the tab spring stiffness in the freeplay state. The ground vibration test is used to measure the model structural dynamic characteristics. Then the experimental aeroelastic model is placed in a low speed wind tunnel to measure the LFV and the limit cycle oscillation (LCO) of the physical model induced by freeplay. The root main square amplitude value of the pitch, flap pitch, tab pitch and plunge degrees of freedom of the tab nonlinearities are normalized with freeplay gap size to produce a bifurcation diagram with normalized airflow velocity as the bifurcation parameter. The results show that the LCO frequency jumps from low to high frequency at a yet higher flow velocity. At the same flow velocity, the pitch and plunge motion response amplitudes drop while the flap pitch and tab pitch degrees of freedom response amplitude increase. In general the experimental measured LCO is more complicated than the theoretically calculated LCO in terms of the harmonic content of the response. On the other hand there is good agreement between the theoretical and experimental result of the linear system as well the LCO for the tab freeplay nonlinearities

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Publication Date
Mon Mar 01 2021
Journal Name
Iraqi Journal Of Physics
Linear and Non-Linear Optical Properties for Organic Semiconductor (CuPc) Thin Films
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Thin films of CuPc of various thicknesses (150,300 and 450) nm have been deposited using pulsed laser deposition technique at room temperature. The study showed that the spectra of the optical absorption of the thin films of the CuPc  are two bands of absorption one in the visible region at about 635 nm, referred to as Q-band, and the second in ultra-violet region where B-band is located at 330 nm. CuPc thin films were found to have direct band gap with values around (1.81 and 3.14 (eV respectively. The vibrational studies were carried out using Fourier transform infrared spectroscopy (FT-IR). Finally, From open and closed aperture Z-scan data non-linear absorption coefficient and non-linear refractive index have been calculated res

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Publication Date
Tue Sep 20 2022
Journal Name
Journal Of The College Of Basic Education
Building challenge test for basic skills in soccer for students -third stage
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The skill scale in most of sport activity monitoring a lot of dynamic behaviours conducted with playing situations that help the excerpt's in sport field to evaluate and put right solutions ,soccer one of games that studies in third stage in college and take skills ,dribbling , passing, shooting these skills helps to execute the plans in game ,the researchers notice that there is no test measure the skills of the game in the beginning of the first semester especially in the method of soccer in physical education college and the problem of the research were by answering the question that is there test connect between one or more that one of skill to measure the ability of students to execute the plans in soccer and the conclusion was the bui

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Publication Date
Sat Jul 04 2020
Journal Name
College Of Islamic Sciences
commiseration for lovers Study in Indication Synthetic Lamentation "Kuthaira Ouza" for instance
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There  is no doubt  various of situations for performing  a duty , The diversity of stimuli in humans with sensory, unconscious and instinct sensitive systems. Which leads to a diversity of feelings, sensations, emotions and feelings, This therefore requires different types of function linguistic structures indication , Of that linguistic potential that God willing to be unique, In the function of discharging and venting those feelings and emotions that are raised by its various stimuli, which are only needs and psychological and biological purposes require verification and access and gain it. So the language became to embrace the feelings and feelings, needs and purposes. And mirror reflected and binoculars revealing what

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Publication Date
Sat Sep 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Production Function Analyze For Almansoor General Company For Engineering Industries In Iraq
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The production function forms one of the techniques used in evaluation the  production the process for any establishment or company, and to explain the importance of contribution of element from the independent variable and it's affect on the dependent variable. Then knowing the elements which are significant or non-significant on the dependent variable.

    So the importance of this study come from estimating the Cobb-Douglas production function for Al- Mansoor General Company for Engineering industries in Iraq during the period (1989-2001)

     To explain the importance which effects the independent variable such as
(N

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Publication Date
Sun Mar 29 2020
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Water Injection for Oil Recovery in Mishrif Formation for Amarah Oil Field
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The water injection of the most important technologies to increase oil production from petroleum reservoirs. In this research, we developed a model for oil tank using the software RUBIS for reservoir simulation. This model was used to make comparison in the production of oil and the reservoir pressure for two case studies where the water was not injected in the first case study but adding new vertical wells while, later, it was injected in the second case study. It represents the results of this work that if the water is not injected, the reservoir model that has been upgraded can produce only 2.9% of the original oil in the tank. This case study also represents a drop in reservoir pressure, which was not enough to support oil production

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Publication Date
Thu Feb 28 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Use Of Artificial Neural Networks In Developing The Role Of Auditor In Discovering Fundamental Errors: An Applied Research In General Company for Electrical Industries and Nasr General Company for Mechanical Industries
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Artificial neural networks usage, as a developed technique, increased in many fields such as Auditing business. Contemporary auditor should cope with the challenges of the technology evolution in the business environment by using computerized techniques such as Artificial neural networks, This research is the first work made in the field of modern techniques of the artificial neural networks in the field of auditing; it is made by using thesample of neural networks as a sample of the artificial multi-layer Back Propagation neural networks in the field of detecting fundamental mistakes of the financial statements when making auditing. The research objectives at offering a methodology for the application of theartificial neural networks wi

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Publication Date
Mon Feb 01 2021
Journal Name
International Medical Journal
Use of immunohistochemistry and silver in situ hybridization (Sish) in evaluation of human epidermal growth factor receptor2 (HER2/neu) status in Iraqi patients with breast cancer
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Breast cancer is the commonest cause of cancer related death in women worldwide. Amplification or over-expression of the ERBB2 (HER/neu) gene occurs in approximately 15-30% of breast cancer cases and it is strongly associated with an increased disease recurrence and a poor prognosis. Determination of HER2/neu status is crucial in the treatment plan as that positive cases will respond to trastuzumab therapy. It has been used to test for HER2/neu by immunohistochemistry as a first step and then to study only the equivocal positive cases (score 2+) by in situ hybridization technique. The aim of our study is to compare between immunohistochemistry and silver in situ hybridization (SISH) in assessment of human epidermal growth factor (HER2/neu)

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Publication Date
Wed Dec 30 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Estimation of Serum CD200 and CD200R1 Levels in a Sample of Iraqi Women with Breast Cancer: Their Role as Diagnostic and Prognostic Markers
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Breast cancer is a disease in which cells in the breast grow out of control. CD200 is a cell surface glycoprotein expressed on many cells, it belongs to the immunoglobulin family (Ig) and have a great role in the regulation of inflammation in autoimmunity. CD200 is the ligand for CD200R1 receptor. To determine if serum level of CD200 and its receptor CD200R1 can be used as a diagnostic and prognostic marker in patients with breast cancer.This case control study was carried out at Oncology Teaching Hospital – Medical city in Baghdad. Six groups were enrolled, four groups were confirmed with breast cancer stage (I, II, III and IV), fifth group (benign) and sixth group was control (healthy individual). Serum is divided to me

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Publication Date
Mon Jun 22 2020
Journal Name
Baghdad Science Journal
Histological and Biochemical Parameters Follow-up in Experimental rats Administrated dexamethasone and Treated with Green Synthesis Titanium Dioxide Nanoparticles Using (Camillia sciences) Extracts
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In this study, Titanium Dioxide Nanoparticles were synthesized by an easy and eco-friendly technique (green synthesis) using green tea leaves (Camillia sinensis), Nanoparticles were analyzed using structural and optical analysis, the X-ray pattern showed that Titanium Dioxide NPs had a tetragonal structure with (Face Centered Tetragonal) FCT crystal structure, the UV-visible recorded an absorbance peak near 350 nm and calculated energy band gap was 3.5 eV, all measurements were proved the purity and Nano size of prepared Nanoparticles. Biochemical parameters evaluation also mentioned in this research, these analyzes showed that Titanium Dioxide nanoparticles in particular dose (50 mg/kg) have the ability to reduce blood glucose

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Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Clinical And Experimental Dentistry
In vitro bond strengths post thermal and fatigue load cycling of sapphire brackets bonded with self-etch primer and evaluation of enamel damage
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Background: This in vitro study compares a self-etch primer (SEP) to an etch-and-rinse (EaR) for bonding sapphire brackets by evaluation of the enamel etch-pattern, shear bond strength, amount of remnant adhesive and enamel surface damage following thermal and fatigue cyclic loading. Material and Methods: Ceramic (sapphire) brackets were bonded to 80 extracted human premolars using two enamel etching protocols: conventional EaR using 37% phosphoric acid (PA) gel (control), and a SEP (Transbond Plus). Each group was subdivided into two subgroups (n=20 teeth) according to the time of bracket debonding: after 24 h water storage or following 5000 thermo-cycles plus 5000 cycles fatigue loading, to determine the shear bond strength (SBS), adhesiv

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