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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 Mar 06 2002
Journal Name
Journal Of Engineering
The effect of technology on interior space
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Publication Date
Sat May 23 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Studying the effect of addition a composite of silanized Nano-Al2O3 and plasma treated polypropylene fibers on some physical and mechanical properties of heat cured PMMA denture base material
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Background: Polymethyl methacrylate (PMMA) is the most commonly used material in denture fabrication. The material is far from ideal in fulfilling the mechanical requirements, like low impact and transverse strength, poor thermal conductivity. The purpose of this study was to evaluate the effect of addition a composite of surface treated Nano Aluminum oxide (Al2O3) filler and plasma treated polypropylene fiber (PP) on some properties of denture base material. Materials and methods: One hundred fifty prepared specimens were divided into 5 groups according to the tests, each group consisted of 30 specimens and these were subdivided into 3 groups (unreinforced heat cured acrylic resin as control group),reinforced acrylic resin with( 0.5%wt Nan

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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Effect of electronic governance in Auditing Quality Research applied at the Economic Organization
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The research paper aims to highlight the impact of electronic governance in improving the quality of auditing through accounting disclosure and how to make use out of it in resolving many of the problems by economic units in general and in particular the financial problems in particular. It focuses on the most important financial information of the loss of confidence and credibility in the financial information of the economic units, This study  has  been carried out through the use and application of many of the principles and rules contained in the electronic governance, The most important Which is the accounting disclosure, and hence the dimensions of accounting for electronic governance through the achievement of ac

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Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Rational Emotional Visualization Style in Reducing Fear of Failure among Athletes
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The research seeks to design a program of guidance in the form of emotional perception rational to reduce the fear of failure, to identify the effect of method of emotional perception rational in reducing the fear of failure. To achieve these objectives, the researcher adopted the null-hypotheses, which assume there are no statistically significant differences in the degree of fear of failure (for the control group) in the pre-posttest. There are no statistically significant differences in the fear of failure (for the experimental group) in the pre-posttest. There were no statistically significant differences in the fear of failure of the groups (experimental and control) after the application of the program in the post-test. In order to

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
THE IMPACT OF CURRENCY AUCTION ON THE VARIABILITY OF THE EXCHANGE RATE IN IRAQ 2004-2015
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The transition states that Iraq economy lived it after 2003, and the change in tools used by monetary policy based on C.B.I law 56 in 2004, under the especially situation for the economy (structural imbalances and the weakness of banking & financial sector).

The monetary policy adopted the inflation targeting policy to mantain the monetary stability in the economy and considered it an incubator for future growth. It used the exchange rate as a nominal anchor to achieve the goal (because the rentier of economy, finance Shallowness & separation between real sector and finance sector, all this cause the normal channel to transfer the effect of monetary policy (interest rate) ineffective.

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Publication Date
Fri Jan 01 2021
Journal Name
Journal Of Economics And Administrative Sciences
Measuring and analyzing the effect of foreign debt on the gross domestic product in Morocco for the period 1990-2017 using the ARDL Test
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The research aims to identify the magnitude of the impact of external debt on the gross domestic product in Morocco, and the importance of research lies in the role that external debt plays in addressing structural imbalances, if it is best disposed of according to well-studied economic plans by specialists in this regard, especially if these debts are directed with Other resources, as it helps pay the costs of these debts (debt servicing) that the external debt also raises the level of gross domestic product, and the research starts from the hypothesis that: There is an effect of foreign debt on the GDP in Morocco, has contributed in one way or another to The exacerbation of the external debt, which affected the m

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Publication Date
Tue Feb 01 2022
Journal Name
Baghdad Science Journal
Study the Inhibition Effect of Amoxicillin Drug for Corrosion of Carbon Steel in Saline Media
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          Potentiostatic polarization and weight loss methods have been used to investigate the corrosion behavior of carbon steel in sodium chloride solution at different concentrations (0.1, 0.4 and 0.6) M under the influence of temperatures ( 293, 298, 303, 308 and 313) K. The inhibition efficiency of the amoxicillin drug on carbon steel in 0.6 M NaCl has also been studied based on concentration and temperature. The corrosion rate showed that all salt concentrations ( NaCl solution) resulted in corrosion of carbon steel in varying ratio and 0.6 M of salt solution  was the highest rate (50.46 g/m².d). The results also indicate that the rate of corrosion increases at a temperature of 313 K.. Potentiodynamic polarization studi

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Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
THE EFFECT OF SPREACL of KNOWLEDGE ON ETHICS
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THE EFFECT OF SPREACL of KNOWLEDGE ON ETHICS

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
The effect of self management in the hardiness at work / study analytic in hospital Alshaheed Gaze Alharery
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The research is Concerned the Relationship between Self Management which is a modern administrative term and its dimensions "Self Control, Trust, and Conscientiousness" with the Hardiness and its dimensions "Challenge, Commitment, and Control". And the impact of the first variable on the second in The Hospital of Alshaheed Gaze Alharery.

The Questionnaire used and distributed on sample (60) Persons, contain from (40) Doctor, and (20) Employees from the total society (103).

The statistical methods have been used for testing the hypothesis is the mean, standard deviation correlation coefficient.

    The resea

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
The effect of Investment in Human Capital on Economic Growth in Algeria A standard Study within the period of: 1970 – 2015
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The summary:

This research paper presents a standard economic study. This study aims to build an economic standard form of the investment effect in Human Capital on Economic Growth in Algeria. The study showed that there is an inverse relationship between the investment and human capital. This is expressed by expending on education and economic growth. This contradicts with the economic theory. Such matter could be explained by that expending on education does not contribute in the economic growth. This refers to that the education sector result does not employee or save jobs. Thus, it does not contribute in growth; in addition, the Algerian economy depends on petrol in the first class. This means the ab

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