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 tunnel test .The flutter speed was calculated analytically for different ply orientation, it is found that the increasing in torsion rigidity leads to increase in the flutter speed, the fiber combination with high torsion rigidity and relatively low coupling rigidity give higher flutter speed.
Background: A great dental and biomedical interest had been paid to silver nanoparticles because of their antimicrobial activity. Objective: To evaluate the antimicrobial and cytotoxic activity of a newly developed Nano-silver fluoride that was synthesized from moringa oleifera leaf extract against S. mutants. Material and method: The green synthesis method was used to prepare Nano-silver fluoride from moringa oleifera leaf extract. The minimum inhibitory concentration and the minimum bactericidal concentration were evaluated using brain heart infusion plates, while the cytotoxicity was evaluated by the hemolytic activity. Results: Nano-silver fluoride had a bactericidal and bacteriostatic effect (MIC was 60 ppm a
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El horóscopo que es una predicción deducida de la posición de los astros del sistema solar y de los signos de Zodiaco, intenta no sólo predecir el futuro, sino también influir en el comportamiento del lector, orientándolo para que actúe adecuadamente y la invitación a actuar ante ese futuro que se aconseja mediante imperativos, perífrasis y otros recursos lingüísticos. Los horóscopos se caracterizan por su gran popularidad que existen en periódico o revista en columnas enteras dedicadas al tema, en donde se detallan la influencia que tendrá el día o el mes de cada uno de los signos correspondientes al zodíaco, siempre teniendo en cuenta la posici
... Show MoreIn the age of information and communication revolution, education as one of life aspects has influenced with that revolution by integrating technology in education, which have become as an important learning tools of the whole educational process . Technology, when used appropriately, can help make science classroom a site of active learning and critical thinking, furthering student inquiry and connections with different materials. It is necessary to develop human rights education programs and materials for discretionary and extracurricular activities as it provide them with the skills and tools so that they are empowered to take action to realize their rights. Human rights education is a critical means of instilling the knowledge، skil
... Show Morethe Current research aims to identify the psychological stressors coping strategies and their relationship to the cognitive motivation among Al-Anbar University students through the following hypotheses: 1) no statistically significant differences at a level (0.05) among the sample according to the instrumental support strategy depending on the variable type and specialization, 2) No statistically significant differences at a level (0.05) among the sample in regard of coping avoiding strategy depending on the variable type and specialization, 3) There is no statistically significant difference at a level (0.05) in cognitive motivation level among Al-Anbar University students, 4) No statistically significant differences at a level (0.05)
... Show MoreThe current study aims to examine the level of problems faced by university students in distance learning, in addition to identify the differences in these problems in terms of the availability of internet services, gender, college, GPA, interactions, academic cohort, and family economic status. The study sample consisted of (3172) students (57.3% females). The researchers developed a questionnaire with (32) items to measure distance learning problems in four areas: Psychological (9 items), academic (10 items), technological (7 items), and study environment (6 items). The responses are scored on a (5) point Likert Scale ranging from 1 (strongly disagree) to 5 (strongly agree). Means, standard deviations, and Multivariate Analysis of Vari
... Show MoreThe research tagged with the controversy of aesthetic interpretation between the sculptures and their titles in contemporary Iraqi sculpture, “Exhibition of Experiments in Contemporary Iraqi Sculpture as a Model”, and it is one of the new research that contributes to strengthening the critical path in the Iraqi fine movement, as the first chapter dealt with the research problem stemming from the question: What is the impact of the aesthetic hermeneutic controversy between the title and the title in contemporary Iraqi sculpture?, and do the titles of the sculptural works help to understand or enhance their contents?, The research objective included: To identify the controversy of the aesthetic interpretation of sculptures and their ti
... Show MoreThis research was distributed into two sections, the first section was concerned with the concept of value for De Saussair and its methodological impact on his linguistic structural conceptions with respect of the distinction between synchronism and diachronism, the value role of linking function between the sounds and the though, the basing of his theoretical conception on the language being a form and not a material according to this principle and the value impact on the demonstration that the linguistic element acquires its functional importance from the relations inside the language system. It also stopped at the methodological impact of value on defining the analytical linguistic unit and the value role in semantics through the prin
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Summary
The book (Fatah al-Rahman reveals what is ambiguous in the Qur’an), which is a book of verbal similarities that tries to touch the Qur’an expression, and the subtle differences between its expressions and expressions. It appeared when it appeared in many chapters, from which I chose to delete in monolithic letters such as Ba and Ta, and to heal and delete in non-monosymbols such as (that) and (may) and (no), so the search came to two chapters The first is for deleting the monolithic letters, and the second is for deleting non-monosyllabic letters, preceded by introductory discussions revolving around the linguistic and idiomatic definition of deletion, a brief translation of the
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