The aerodynamic and elastic forces may cause an oscillation of the structure such as the high frequency of the airfoil surfaces and the dynamic instability occurring in an aircraft in flight and failure may occur at a speed called flutter speed. In this work, analytical and numerical investigations of flutter limits of thin plates have been carried out. The flutter speed of rectangular plates were obtained and compared with some published results. Different design parameters were investigated such as aspect ratio, thickness and their effects on flutter velocity. It was found that the structural mode shape plays an important role in the determination of the flutter speed and the coupling between the bending and torsional mode is the main cause of flutter.
Abstract
The grey system model GM(1,1) is the model of the prediction of the time series and the basis of the grey theory. This research presents the methods for estimating parameters of the grey model GM(1,1) is the accumulative method (ACC), the exponential method (EXP), modified exponential method (Mod EXP) and the Particle Swarm Optimization method (PSO). These methods were compared based on the Mean square error (MSE) and the Mean Absolute percentage error (MAPE) as a basis comparator and the simulation method was adopted for the best of the four methods, The best method was obtained and then applied to real data. This data represents the consumption rate of two types of oils a he
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اعفاء عقود تراخيص الملكية الصناعية من الحظر وفقا للقانون الامريكي و الاوربي
El sumario
“la lluvia amarilla” en una novela española que es una obra biográfica de un Aldeano hombre muerte, Andrés, quien niega abandonar su pueblo, Ainielle, y después la muerte de su esposa, la vida estaba difícil y las memorias comenzaron a perseguirlo, sus Los familiares de los fallecidos comenzaron a venir en su imaginación y sentarse delante de la chimenea y le llame a ir con ellos.
Nuestra novela del autor Julio Llamazares es llena de figuras retoricas y para dar un profundo visión de las metáforas principales que son (la lluvia, el color amarillo y la soga) realizamos un estudio analítico con el Corán sagrado y hemos visto los riesgos de las diferencias y similitudes en los
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Este trabajo de investigación ofrece uno de los temas relevantes en la lengua, el cual es estudiar las dimensiones sintácticas, semánticas y pragmáticas de las preposiciones, en general, y de las dos preposiciones "Para" y "Por" en concreto, en una unidad linguística más amplia que la llamada "Oración". En la parte referida al estudio de las dos preposiciones mencionadas, estudiamos sus distntos usos funcionales, usos que se acercan, unas veces, entre sí y se alejan en otras.
Abstract
... Show Moreإن الاستخدام الفعال للأموال العامة يشكل احد الدعامات الأساسية من اجل حسن إدارة تلك الأموال و فعالية القرارات الصادرة عن السلطات المختصة ، و أن هذا الهدف لا يتحقق ما لم تكون الرقابة المالية ذات فعالية لكبح جماح حالات الفساد الإداري النظمي و تفشي ذلك في جهاز الدولة الإداري. لان ظاهرة الفساد الإداري تؤدي بجهاز الدولة الإداري إلى فقدان كيانه الموحد لصالح المنظومات الفاسدة رغم احتفاظه بكيانه الموحد شكليا، كما ت
... Show MoreHumanity has Suffered Greatly from the Economic crisis and instability, Before the Emergence of the rule of the Capitalist System, However, the reaons were Different. But almost Completely Contradictory. At a time When the Causes of the Crisis was due to the time Factor is the product of failure of productie forces, Bears modern Crises resoled by the progress that is in the embrace of the abundance, and as far as lies in the nature and content of the capitalist system itselfas a system based on the creation of productive capacities in excess unable to accomplish through demand by the chaos of production based, on the logic of the market on one hand, and the nature of the output and direction. On the other hand the relations
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معيار القصديَّة في النص هو من الدراسات الحديثة المتطورة من لسانيات الجملة الى لسانيات النص ، وتحليل الخطاب . والذي يعنى بالطرق والأدوات التي يستغلها المؤلف لتحقيق الغايات المقصديَّة
وهذا البحث ناقش مفهوم(القصديَّة) لغةً ،واصطلاحاً . فاللغة والكلام شكل من أشكال الوجود الإنساني و( الكلام) هو وسيلة التواصل بين الملقي القارئ ، والمتلقي السامع ؛ وللتوصل الى الدلالة القصديَّة الدقيقة للغة المنطوقة وا
... Show MoreThe phenomenon of Masculine and feminine is one of the important grammatical studies because of their influence on the sentence structure, words come either masculine and feminine type when using one of them in place of the other , this displacement might cause distribution in the sentence itself because,
Almost human societies are not void of poverty, as the latter accompanied the emergence of humanity, and it, thus, represents an eternal problem. To advance an individual's reality and raise the level of the poor social classes, social security networks have been established. Such networks operate in society following social systems and laws to provide food, and material support. Besides, such networks help to rehabilitate the individual academically and vocationally. They empower vulnerable groups through the establishment of courses and workshop, provide (conditional) subsidies related to the health and educational aspects in order to achieve the sustainable development goals of (2030), and apply developmental roles of social safety ne
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Evaluation is one of the most important elements of teaching process. The recent trends in evaluation and educational reform movements have called for using alternative evaluation, which focuses on performance evaluation. Authentic assessment is usually described as formative, in which students participate in their acquisition, in addition to the fact that students are productive and active, which is reflected in the students' achievement and skill level. The study aims to reveal the degree of knowledge and use of alternative assessment tools by primary school teachers in Gaza -Palestine. To meet the objective of the study, the researchers used the descriptive-analytical method and the questioner as a study tool. The study sample c
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