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The Effect of Wind Velocity on the Suppression of Composite Wing Airfoil NACA 0012
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The first studies on shocks and vibrations were carried out at the beginning of the 1930s to improve the behavior of buildings during earthquakes. Vibration tests on aircraft were developed from 1940 to verify the resistance of parts and equipments prior to their first use. Flutter is a well-known example of dynamic aero elasticity, where when oscillation of structure interacted with unsteady aerodynamic forces the flutter will occur. Vibration on any structure without damping means that self-harmonic oscillation will occur, and in most cases the oscillation may start to increase until structural failure. This behavior is very similar to resonance phenomena if only the oscillation is being studied as a vibration case. In vibration suppression, the active vibration control is one of the more effective technique which is used for attenuating bad effects of disturbances on structure. In this work, two different composite wings have been used; one of them is made of Glass-fiber random matt and the other is made of woven ({0/90} Glass-fiber). The proportional-integral-derivative (PID) control is employed here for studying the suppression of active vibration wing affected by wind velocity flow through wind tunnel in the laboratory of mechanical engineering department at the university of Baghdad. Piezoelectric (PZT (transducers are used as sensors and actuators in vibration control systems. The attack angle was 10 degrees and three different velocities (15, 20, 35 m/s) have been taken to show their effect on the wings vibrations suppression. Is noticed that the suppression of the wing amplitude is reduced when the wind velocity increases for both woven and random composite wing matt. This is happened due to the vortex which has became more violent increase in wind velocity. It is concluded that the composite woven wing has high resistance more than the composite random wing. Also, the maximum control amplitude of woven matt is 1.9 cm and the damping is about 33% at 25 m/s wind velocity while the amplitude is 2.22 cm and the damping is about 53% at 10 m/s wind velocity for random wing.

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Publication Date
Wed Jan 29 2025
Journal Name
Jornal Brasileiro De Patologia E Medicina Laboratorial
First Report of Three Root-Maggot Fly Genera (Diptera: Anthomyiidae) in the Fauna of Iraq
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Publication Date
Sun Jan 03 2021
Journal Name
Le Infezioni In Medicina
Airborne transmission of SARS-CoV-2 is the dominant route of transmission: Droplets and aerosols
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Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a pandemic worldwide. On a daily basis the number of deaths associated with COVID-19 is rapidly increasing. The main transmission route of SARS-CoV-2 is through the air (airborne transmission). This review details the airborne transmission of SARS-CoV-2, the aerodynamics, and different modes of transmission (e.g. droplets, droplet nuclei, and aerosol particles). SARS-CoV-2 can be transmitted by an infected person during activities such as expiration, coughing, sneezing, and talking. During such activities and some medical procedures, aerosols and droplets contaminated with SARS-CoV-2 particles are formed. Depending on their

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Scopus (72)
Scopus
Publication Date
Tue Mar 01 2022
Journal Name
Journal Of Engineering
Numerical Investigation of the Flexure Behavior of Reinforced Concrete Spandrel Beams with Distributed Tension Reinforcement
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When the flange of a reinforced concrete spandrel beam is in tension, current design codes and specifications enable a portion of the bonded flexure tension reinforcement to be distributed over an effective flange width. The flexural behavior of the RC L-shaped spandrel beam when reinforcement is laterally displaced in the tension flange is investigated experimentally and numerically in this work. Numerical analysis utilizing the finite element method is performed on discretized flanged beam models validated using experimentally verified L-shaped beam specimens to achieve study objectives. A parametric study was carried out to evaluate the influence of various factors on the beam’s flexure behavior. Results showed that

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Publication Date
Sun Oct 06 2024
Journal Name
International Journal Of Advances In Engineering And Management (ijaem)
The makers of sedition in light of Chapters (Al-Baqarah and Yusuf)/An objective study
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The makers of strife exist in every era and time. They differ in how these temptations are created and the methods used in doing so. In our modern era, they are more; This is due to the presence of information technology and its easy availability at their fingertips, as well as the spread of social networking sites, which are rapidly spreading among ignorant groups and groups that are deficient in their use. Which led the makers of sedition to exploit these matters and create various temptations and spread them among peoples and societies. Today, we cannot predict the future of humanity in light of this huge amount of temptation. What the Holy Qur’an mentioned about the types of temptations in its noble verses and their embodiment in seve

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Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Ab–Initio large unit cell calculations of the electronic structure of Si and Ge nanocrystals
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Ab – initio restricted Hartree - Fock method within the framework of large unit cell (LUC) formalism is used to investigate the electronic structure of Si and Ge nanocrystals. The surface and core properties are investigated. A large unit cell of 8 atoms is used in the present analysis. Cohesive energy, energy gap, conduction and valence band widths are obtained from the electronic structure calculations. The results are compared with available experimental data and theoretical results of other investigators. The calculated lattice constant is found to be slightly larger than the corresponding experimental value because we use only 8 atoms and we compared the results with that of the bulk crystals, nanoclusters are expected to have str

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Publication Date
Mon Apr 15 2019
Journal Name
Journal Of Global Pharma Technology
The dual role of Gentamicin in gene expression of fibronectin binding proteins in Staphylococcus aureus
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Objectives: The current work aimed to reveal the impact of gentamicin on the fibronectin binding proteins (fnbp) gene expression and its relation to biofilm and agr type in Staphylococcus aureus. Materials and Methods: A total of 25 S. aureus isolates were enrolled in this study previously isolated from different specimens. Identification confirmation and methicillin resistance were achieved by amplification of 16SrRNA and mecA. Multiplex polymerase chain reaction (PCR) based assay was employed to evaluate the agr typing. The gene expression of fnbA and fnbB genes was tested by real-time PCR technique. Minimum inhibitory concentration was estimated by micro broth dilution methodology. Microtiter plate method was performed to determine the a

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Publication Date
Sun Sep 30 2012
Journal Name
College Of Islamic Sciences
Meaning of formulation غ more actions      In Surat Al-Baqarah at the pride of honor
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Praise be to God, who started his book with the praise of himself and prayers and peace be upon those who do not have a prophet after him and his family and companions and those who followed them with charity until the Day of Judgment. Either:
      The research examines the meanings of the formulas of the increased verbs that were mentioned in Surat Al-Baqara, at the imam of the imams of the Islamic nation, namely, Al-Fakhri Al-Razi (d. 606 AH), may God Almighty have mercy on him. With the imams of Quranic scholars.

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Publication Date
Sat Jan 01 2022
Journal Name
Revista Iberoamericana De Psicología Del Ejercicio Y El Deporte
CIVILIZED CLEVERNESS AMONG STUDENTS OF THE FACULTIES OF PHYSICAL EDUCATION SPORTS SCIENCES AND FINE ARTS
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Scopus (2)
Scopus
Publication Date
Tue Aug 01 2023
Journal Name
Journal Of Engineering
The Role of Project Health Check Reports in Identifying Indicative Factors of a Troubled Project
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Government-sponsored projects in Iraq significantly improve the economic situation and provide services but face high rates of troubling blocks. This work aims to identify indicative factors of the Troubled Project using periodic health check reports based on a literature review and interviews with Iraqi experts. As a result, a questionnaire was prepared that included four sections. The first is personal information; the second section is information about knowing the level of institutions’ implementation of project management through prepared documents. The third section is about indicative factors for the project's trouble, including 25 workers; the fourth section is about the questions in the periodic reports to che

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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Split and Merge Regions of Satellite Images using the Non-Hierarchical Algorithm of Cluster Analysis
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يعد التقطيع الصوري من الاهداف الرئيسة والضرورية في المعالجات الصورية للصور الرقمية، فهو يسعى الى تجزئة الصور المدروسة الى مناطق متعددة اكثر نفعاً تلخص فيها المناطق ذات الافادة لصور الاقمار الصناعية، وهي صور متعددة الاطياف ومجهزة من الاقمار الصناعية باستخدام مبدأ الاستشعار عن بعد والذي اصبح من المفاهيم المهمة التي تُعتمد تطبيقاته في اغلب ضروريات الحياة اليومية، وخاصة بعد التطورات المتسارعة التي شهد

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