Based on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore the variation of Lyapunov exponent parameter as function of time is introduced. The numerical result indicated that the system became lightly damped at high angle of attack with increasing the amplitude of aircraft state variables limit cycle. A good agreement between the numerical result and published work is obtained for the onset of limit cycle oscillation, almost at .
A dynamic analysis method has been developed to investigate and characterize embedded delamination on the dynamic response of composite laminated structures. A nonlinear finite element model for geometrically large amplitude free vibration intact plate and delamination plate analysis is presented using higher order shear deformation theory where the nonlinearity was introduced in the Green-Lagrange sense. The governing equation of the vibrated plate were derived using the Variational approach. The effect of different orthotropicity ratio, boundary condition and delamination size on the non-dimenational fundamental frequency and frequency ratios of plate for different stacking sequences are studied. Finally th
... Show MoreYou Mohammed, you're prophet of God and I'm Gabriel)). With this heavenly call which Mohammed, the messenger of God (may God's mercies be on him), got and when he left Hiraa cave and after getting the aye ((read with your God's name)), a new period of mankind's history started. From that time, the greatest state was established. There was no public treasury and no public financial resources at that time. Abu Baker (God bless him) spent a lot of money to support the costs of the new mission. After Al-Hijra, the bases of establishing the Islamic state were available but it lacked administrative and financial organizing. Therefore the prophet was very keen to find Islamic system which ensures justice and availability of
... Show Moreان شركات التأمين وبسبب طبيعة نشاطها التأميني تتجمع لديها أموال ضخمة عن الأقساط التي تحصلها من المؤمن لهم, ولغرض عدم ترك هذه الاموال عاطلة, فأنه يتم استثمارها في مجالات وأدوات استثمار متنوعة لتحقيق عوائد منها. هذا ولغرض تحديد وتوجيه هذه الاموال في مجال أو أداة الاستثمار المناسبة أو تحديد مدى جدوى هذه الاستثمارات, فانه يتم تقييمها, وهناك عدة نماذج رياضية لتقييم بدائل الاستثمار في شركات التأمين, إلا أنه لا
... Show MoreThis research aims to identify the impact of Daniel's model on the development of critical thinking. In order to achieve this objective, the following hypotheses are formulated: 1. There is no statistically significant difference at the significance level (0.05) between the average differences in the posttest scores of the experimental group taught according to Daniel's model and the control group taught according to the traditional method in the measure of critical thinking. 2. There is no statistically significant difference at the significance level (0.05) between the average differences in the preand post-tests scores of the experimental group taught according to Daniel's model in the measure of critical thinking. The current research i
... Show Moreالتعددية السياسية بين الرفلض والقبول دراسة نظرية لأبرز الاتجاهات الاسلامية المعاصرة
Every era characterizes with its thought and life philosophy , where Muslims left behind them educational and intellectual heritage we should proud of it because it reflects the image of past and lights the way of present and future path where we should make use of it to fit with our statuesque and contemporary issues because we don’t know about it but little as result of ignorance or imitation of the western culture.
It’s wrong to regard heritage from the past but aphasia of Islamic and Arab genies that its roots tracing back to past and extending to future .
Islamic Arab educational thought regards one of the ric
... Show MoreThe effect of cognitive trips via the Internet (web quest) accompanying practical lessons in learning some basic handball skills for female students
Growth hormone deficiency is a condition that occurs when a limited volume of growth hormone is released by the pituitary gland since growth hormone deficiency causes growth delays, short stature, and overall physical development delays. symptoms differ based on the age at which they occur .Aim of this study Estimating the level of growth hormone serotonin ,IGF-1 and Chromogranin A before and after with treatment recombinant growth hormone and It is the first study in Iraq that sheds light on the relationship between Chromogranin and other variables ( somatostatin, IGF-1,GH) ,also the prediction of Chromogranin A as a newly biochemical marker in children with growth hormone deficiency. In this study, 30 samples were collected from children
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