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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
Sun Oct 01 2017
Journal Name
Journal Of Engineering
Comparison the Physical and Mechanical Properties of Composite Materials (Al /SiC and Al/ B4C) Produced by Powder Technology
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In this investigation, metal matrix composites (MMCs) were manufactured by using powder technology. Aluminum 6061 is reinforced with two different ceramics particles (SiC and B4C) with different volume fractions as (3, 6, 9 and 12 wt. %). The most important applications of particulate reinforcement of aluminum matrix are: Pistons, Connecting rods etc. The specimens were prepared by using aluminum powder with 150 µm in particle size and SiC, B4C powder with 200 µm in particle size. The chosen powders were mixed by using planetary mixing setup at 250 rpm for 4hr.with zinc stearate as an activator material in steel ball milling. After mixing process the powders were compacted by hydraulic

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Publication Date
Mon Dec 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Analysis of the Effects of Aggressive Shot Peening on Fatigue Life of 7075 – T6 Aluminum Alloy
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 For many years controlled shot peening was considered as a surface treatment. It is now clear that the performance of control shot peening in terms of fatigue depends on the balance between its beneficial (compressive residual stress and work hardening) and beneficial effects (surface hardening).

The overall aim of this paper is to study the effects of aggressive shot peening on fatigue life of 7075 – T6 aluminum alloy. The fatigue life reduction factor (LRF) due to the aggressive shot peening was established and empirical relations were proposed to describe the behavior of LRF, roughness and fatigue life. The benefits of shot peering in terms of fatigue life are dependent on the shot peening time (SPT).

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Publication Date
Fri Jan 01 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Auditor's Evaluation of The Detected Misstatements and Their Reflection on The Administration's Actions is: an Applied Research in the General Company for Grain Processing
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Some auditors may think that the audit process ends with discovering misstatements and informing management about them, while the discovery of misstatements may be classified by some as the first step in the phase of separating these distortions, as the auditor should collect these misstatements, evaluate them and detail them into misstatements involving errors or misstatements involving fraud Then evaluating it to material or immaterial according to what was stated in the international auditing standards and directing management to amend the essential ones.  The importance of this research lies in identifying the concept of distortions and their types, identifying the method of evaluating distortions into substantial and non-essent

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Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Study the effect of adding TiO2 nano-powder on some surface properties of TiO2 thin film prepared on stainless steel substrate
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In this research TiO2 nano-powder was prepared by a spray pyrolysis technique and then adds to the TiO2 powder with particle size (0.523 μm) in ratio (0, 5, 10, 15 at %) atomic percentage, and then deposition of the mixture on the stainless steel 316 L substrate in order to use in medical and industrial applications.
Structure properties including x-ray diffraction (XRD) and scanning electron microscope (SEM0, also some of mechanical properties and the effect of thermal annealing in different temperature have been studied. The results show that the particle size of a prepared nano-powder was 50 up to 75 nm from SEM, and the crystal structure of the powders (original and nano powder) was rutile with tetragonal cell. An improvement in

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Publication Date
Wed Jan 01 2020
Journal Name
Plant Archives
Morpho-physiological study on the effect of lead stress and selenium foliar application on growth of dill plant anethum graveolens l
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The experiment was carried out in the green house of botanical garden belong to Department of Biology/College of Education for Pure Science Ibn AL-Haitham, University of Baghdad for growing season 2017-2018 to evaluate effect of lead stress with concentrations (0, 50, 100, 150) mg.L -1 and Selenium concentrations (0, 15, 30) mg.L-1 on growth of dill plant using pots. The experiment was designed according to completely randomized design (CRD) with three replications. Result indicated that dill plants subjected to lead stress with height concentrations caused decrease in plant parameters (plant height, no. of branches. plant-1, root length, shoot dry weight, the content of nitrogen, phosphorus and potassium, protein concentration, no. of umbe

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Publication Date
Sat Mar 04 2023
Journal Name
Baghdad Science Journal
Nordhaus-Gaddum Type Relations on Open Support Independence Number of Some Path Related Graphs Under Addition and Multiplication
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In this paper, Nordhaus-Gaddum type relations on open support independence number of some derived graphs of path related graphs under addition and multiplication are studied.

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Publication Date
Mon Sep 01 2014
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Forensic accounting role in governance and its impact on the quality of accounting information
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That the structural changes in the environment, business and finance and the spread of business and the diversity of transactions between economic organizations and breadth of a commercial scale in the world have left their clear on the need to keep up with the accounting for these variables as one of the social sciences affect and are affected by the surrounding environment because of the various economic and social factors, technical, legal and others.

As a result of these variables emerged a new field of accounting called Forensic Accounting, which involves the use of expertise of multiple pour in the end to the accounting profession, where the Forensic Accounting cover a large area of ​​disciplines including strengthening

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Publication Date
Mon Jan 16 2023
Journal Name
Iraqi National Journal Of Nursing Specialties
English Influence of Workplace Incivility on Psychological Well-being of Nurses in the Southern of Iraq
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Abstract

Objectives: The main objective of this study is to find the influence level of nursing incivility on psychological well-being among nurses in southeastern Iraq.

Methods: In this descriptive correlational study, a convenience sample of 250 nurses working in three government hospitals in Missan province in the south of Iraq were surveyed using the nursing incivility scale (NIS) and Ryff's psychological well-being scale (PWB) from November 2021, to July 2022. A multivariate multiple regression analysis was done to analyze the multivariate effect of workplace incivility on the psychological well-being of nurses.

Results: The study results show a

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Publication Date
Thu Aug 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Knowledge Sharing In the Human Resource Capability
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Abstract
         The role of the independent variable and human resources capabilities was the role of the adopted variable. The aim of the research is to identify the level of participation in the knowledge of the organization through human resources and the rigorous scientific investigation to develop new mechanisms of action that help To manage the organization in the implementation of its mission and achieve its main objectives that have been found for it is to encourage the work of scientific research and maintain the preservation of its continuity to increase the competencies of knowledge, technical and skill to form a future workforce qualified to work In the sectors of society.

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Publication Date
Wed Jun 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of the Strategic Leadership in Strategic Learning Exploratory Research at Anbar University
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        This study aims to know the extent of the impact of Strategic Leadership as an independent variable in Strategic Learning as a dependent variable to help the senior leadership in Anbar University to take the right decisions to develop Strategic Learning programs in light of the circumstances of the Covid-19 and the sudden decisions adopted by the university to switch to E-learning and to blend. The survey was conducted by distributing a questionnaire that was adopted as a primary tool in data collection from the study sample represented by the university's senior leaders, An intentional random sample of (105) was selected from our community of (127), the data were analyzed by (SPSS) Depe

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