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.
The research aims to study the reliability of government institutions, including the audit directors, which are one of the most important oversight formations in the Ministry of Construction, Housing and Public Municipalities, on which the responsibility for comprehensive auditing of all the Ministry's (municipalities) formations falls on the Managing the Audit Program according to the specification (ISO 19011: 2018) to improve the audit performance which requires compliance with the application of the audit management system in accordance with the standard Specification (ISO 19011: 2018), depending on the methodology of the case study, and using of checklists, which were chosen ac
... Show MoreAbstract:
If we neglect the value of historical fashions as a source of inspiration for
contemporary fashion designers we will neglect a treasure of original designs.
In neglecting such a treasure how could we then know what is original. Today
the most famous fashion designers are often inspired, in the outwardly from
and internal lines of their fashions, by fashion designed during the ages of the
past.
Designers can find such fashions in books of history and museums. But
the historical ages are not equal in the fertility of the originality and novelty of
their fashions. Thus the contemporary designer may not find the old designs
inspiring so he invents them.
The researcher was keen in this paper to inclu
Atheism is one of the most dangerous absurd doctrines that have swept the world in the modern era. Its strength lies in the bodies that stand behind it and adopt its ideologies which are accompanied by the tremendous media momentum of the theses of its supporters based on scientific and non-scientific levels. And since the denial of the existence of the Creator is the main focus and central point which the atheists based their view towards the universe, life and man, this humble research came to discuss the claim of the existence of the world by pure chance, and try to explain this scientifically through the theory of natural selection and survival of the fittest developed by the English biologist Charles Darwin. The resea
... Show MoreАннотация
В данном исследовании рассматривается символичность (( Джикора )) в лирике иракского поэта ас-Саййаба и перевода лирики o деревне и городе с арабского на русский. Русский читатель пока не имеет возможности познакомиться с стихотворениями Бадра Шакера.
Abstract
The paper aims at making the Russian reader acquainted with the Iraqi Poet Badr Shakir as-Sayyab, and showing the effect of the village an
... Show MoreThis study is about the role of the Internet in spreading rumors, especially through social networking sites "Facebook" model as the effectiveness of social networks lies in the speed of transmission of events; these two characteristics are important to the public, making the Internet a strong contender for television and its relationship with the public. That's why we find that the Internet today has become a fertile environment for the growth and spread of rumors. The more limited the platforms and places of publication, the greater the responsibility in the search for the original source in spreading this or that rumor, as the Internet is considered an easy means in the production, spreading and re-spreading of
... Show MoreDealing with this study to find a link principle in the construction of the system and disorder to the promise of the principles and concepts of intellectual and philosophical form and content in the act of interior design of the halls education in the Ministry of Labor and Social Affairs , which leads to a reaction design objective and functionally and to increase the strength of the effect on users of the coaches and trainers . As it informs the side cognitive and developmental study of the design of the interior spaces . So it was the goal of research in the detection of the nature of the system and disorder with Focus indicators and the type of regulations and privacy and what constitutes the framework of knowledge in order to explai
... Show MoreThe use of the word “war” alone raises horror and fear in the hearts of the recipients, especially if this war aimed at human’s life, his health and his future. It is the electronic advertising war among rival international companies that use cyberspace to create fear and horror in the hearts of the recipients because it connects the use of the product with human’s death or serious illness.
The problem of this research sheds light on the new uses of cyberspace which fucked by international companies to strike the interests of each other by displaying the defects of their products and its negative impact on citizen’s life. Despite the fact that those wars have opposed strongly, there are supporters for those wars. Their argu
The expression is a prominent feature of the Arabic language, but it is one of the characteristics that are inseparable from it. The expressive aspects of each other.
The issue of Arab differences and their impact on the divergence of meaning is one of the issues that have preoccupied the minds of the Arabic language owners and their views went to various doctrines. Introduction: (Whenever I finished a question concluded with a verse related to any download, and followed by the need for expressing, interpretation and interpretation) I found him in some of the Aarabip more than the face of some of the vocabulary raised and erected and a jar, when the verses of the Koran, resulting in a research lies between Grammar and the Koran under
The Gulf Cooperation Council (GCC) is the only one in the Arab system, which has been able to formulate a strategic vision with its dimensions and objectives, and that for its great achievements have contributed significantly to the development of the external and internal economic relations of the Gulf Cooperation Council six through the consolidation of economic policies, projects and joint institutions . There is no doubt that the establishment of the Cooperation Council for the Arab Gulf States six, has made security expensive as long as the aspiration to them the leaders and peoples of the region is the adoption of the GCC countries on itself in order to build a self strength ensures cut off the road to all interference in the affai
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