Flutter is a phenomenon resulting from the interaction between aerodynamic and structural dynamic forces and may lead to a destructive instability. The aerodynamic forces on an oscillating airfoil combination of two independent degrees of freedom have been determined. The problem resolves itself into the solution of certain definite integrals, which have been identified as Theodorsen functions. The theory, being based on potential flow and the Kutta condition, is fundamentally equivalent to the conventional wing-ection theory relating to the steady case. The mechanism of aerodynamic instability has been analyzed in detail. An exact solution, involving potential flow and the adoption of the Kutta condition, has been analyzed in detail. Th

The paper presents an investigation to the flutter speed of composite wing for different ply orientation. Structurally the composite wing was idealized as a composite beam load carrying structure. Theodorsen’s expression was used to get the 2- dimension unsteady lifting force and pitching moment in the limit of incompressible flow and subsonic speed which were integrated over the wing span. A free vibration analysis was first carried out to get the natural frequencies and mode shapes .The velocity-damping (V-g) method was used to calculate the flutter speed and the flutter frequency. A wing of unmanned aerial vehicle was manufactured from woven glass and polyester resin where the flutter speed was calculated experimentally by the wind

The study aimed to survey mushroom species from fields among herbs, palm trunks, and trees in central Iraq and to identify them on the basis of morphological and molecular characteristics. As a molecular identification result with polymerase chain reaction six species were recorded (with eight isolates): Agaricus bitorquis (Quéllt) Saccardo. 1887 (SHA14); Candolleomyces candolleanus (Fr.) D. Wächter & Melzer, 2020 (SHA15); Cyclocybe cylindracea (D.C.) Vizzini & Angelini, 2014 (SHA13); Leucoagaricus hesperius Vellinga, 2010 (SHA16); Volvariella sp. (SHA17), and Volvopluteus gloiocephalus (D. C.) Vizzini, Contu & Justo, 2011 (SHA10, SHA101 and SHA12), belonging to four families of Basidiomycetes: Agaricaceae, Pluteaceae,

The research has designed for studying the relationship between manufacturing strategy and its flexibility under the flexible manufacturing system with their reflection on the competitive environmental performance of the firm. To interpret and tackle the problem, a hypothesis has formulated stating that “ the competitive performance of a firm is interpreted by the manufacturing strategy and flexibility which are derived from the firm and its business  strategies under the flexible manufacturing system”. Related literatures with their theoretical dissertations, which enhanced the thoughtful content, have analyzed. An illustrative case study on the flexible manufacturing system at Toyota Motors Corporation working at the g

The aim of this research is to study the extent of the impact of government funding decisions on the financial performance of the directorate of Diyala province. The research problem was based on the financial reality of the directorate, and the data were collected from the financial divisions, planning and follow-up, implementation, and engineers of the resident engineer departments. Demonstrate the impact of government funding decisions on financial performance. Using scientific methods in estimating their financial needs through the annual estimated budget. The use of financial analysis to assess the performance of the Directorate, for the purpose of assessing the financial situation of the Directorate of research. The researc

It is necessary to use the means of recovery and other means that help to get rid of the effects of fatigue, as the game of badminton and the effectiveness of running 800 meters fall within the mixed system with the superiority of the anaerobic system by more than the air system, so requires the development of energy systems In proportion to the time of the match for badminton players and their travels and high performance and ability to tolerate the high level of lactic acid in the muscles and blood and increase the pain associated with the fatigue that occurs during the performance. In light of the physical and physiological processes of these actions N it should seek through training programs to develop your endurance and wind energy sys

Achieving high achievement in the sport of fencing requires thinking, awareness and visual tracking, as visual tracking is one of the important visual abilities that a fencing player needs and is considered one of the special visual abilities as it contributes and helps in the correct motor, mental and mental performance and gives the fencing the ability to perfect and accomplished performance in training and competition. Where the research problem lies in the weak skill performance of the fencing players as a result of the weakness in possessing visual and mental abilities. The two researchers used the experimental method in a controlled manner (experimental and control groups) with a pre and post-test. The research community was identifie

Total Quality Assurance Concept have appeared in Higher Education Institutions as a result of the continuous criticism for the lower quality of the outputs of these institutions and their inappropriacy to the needs of the job market. The faculty, i.e. teaching staff member, is one of the most important output for his/her responsibility to achieve the stated goals in higher education. This represents a problem that may influence the construction of society which has to limit his tasks, responsibilities, and competencies that should be found in a faculty, and evaluating his teaching profession in light of the prerequisites of the century to become an input to achieve quality assurance in Higher Education. Therefore, the present study aims