تعد فعالية دفع الثقل واحده من الفعاليات المميزة بألعاب القوى، وهي أحدى فعاليات الرمي الأربعة (رمي الرمح, رمي القرص, أطاحة المطرقة, دفع الثقل) وتطلب قدرات بدنية وقابليات حركية خاصة والتي تعتمد بشكل فعَال ومؤثر على النواحي البايوميكانيكية, خصوصا عندما يتعلق الأمر بذوي الأعاقة ومنهم فئة (40f) والذين يتمتعون بدعم كبير من المجتمع الدولي بصورة عامة وفي بلدانهم بصورة خاصة وأمكانية تطوير أنجازاتهم لرفع أسم بلدانهم في المحافل الدولية. وتبرز أهمية البحث من خلال تحليل المسار الحركي لبطل العالم العراقي جراح نصار من خلال تحليل بعض المؤشرات البايوميكانيكية لمرحلة وضع القوة (تجهيز القوة) والتي تعتبر من اهم المراحل الفنية المؤثرة بالانجاز النهائي للاعبي دفع الثقل من الزحلقة أن كانوا أسوياء أم من ذوي الإعاقة.وتمحورت مشكلة البحث حول أهمية التعرف على القيم الرقمية للمؤشرات الميكانيكية لأبطالنا الذين حققوا كم من المداليات الملونة لوصف نتائجهم لمدربيهم وزملائهم للعمل على الوصول الى هذه الجزيئات وتطبيقها في تحسين الآداء الفني ورفع مستواهم أضافة الى أهمال الجانب البايوميكانيكي لهذه الفعالية من خلال عدم أستعمال التحليل الحركي والتعرف على نقاط الضعف بدقة عالية في فعالية سريعة لايتجاوز زمن المحاولة فيها الثانيتين أضافة الى عدم الاهتمام من قبل المدربين بخصائص قيم المؤشرات البايوميكانيكية المؤثرة في بعضها البعض لكي يبرمجوا برامجهم التدريبية بغية تحقيق أهدافهم بأسرع مايمكن وتوفيرا للجهد والوقت المبذول.وهدف البحث إلى التعرف على أهم المؤشرات البايوميكانيكية الخاصة بمرحلة وضع القوة وهي طول الخطوة لقدم الأرتكاز وزمن الخطوة لقدم الأرتكاز وسرعة الخطوة لقدم الأرتكاز وزاوية الأسناد وزاوية الدفع وزاوية اتجاه القدم الخلفية في وضع القوة والعلاقة بين هذه المؤشرات مع الإنجاز المتحقق للاعبي ذوي الاعاقة فئة (40f) بدفع الثقل.وأستعملت الباحثتان المنهج الوصفي والعلاقات الأرتباطية في دراستهما الحالية لملائمته طبيعة مشكلة الدراسة وتألف مجتمع البحث من لاعب المنتخب الوطني العراقي فئة (40f) (جراح نصار) أذ تم أخذه بالطريقة العمدية وأجري الأختبار له خلال معسكره التدريبي ببغداد في ملعب كلية التربية البدنية وعلوم الرياضة / الجادرية أستعدادا للبطولات الخارجية وتم أخذ ستة محاولات كما في السباقات الرسمية وتم أستعمال كامرتي تحليل نوع (CASIO FH13.5) بسرعة 120 لقطة بالثانية وتم أجراء عملية التحليل الحركي ببرنامجي التحليل Tracker)) و( Kenova ) أذ تم أستعمال برنامج Tracker)) لقياس المسافات والازاحات والأرتفاعات المتحققة وتم أستعمال برنامج(Kenova) لقياس السرعة والتعجيل والأزمان المتحققة لعينة الدراسة وبعد تحليل ومناقشة النتائج توصلت الباحثتان الى وجود علاقة أرتباط طردية بين طول الخطوة لقدم الأرتكاز وسرعة الخطوة لقدم الأرتكاز علاقة أرتباط عكسية بين زمن الخطوة لقدم الأرتكاز والإنجاز وعدم وجود علاقة أرتباط بين زاوية الأسناد وزاوية الدفع وزاوية اتجاه القدم الخلفية مع الأنجاز وفي ضوء ذلك توصي الباحثتان باجراء دراسات موسعه لهذه الفعالية لتشخيص نقاط الضعف والقوه في الأداء الفني والاهتمام بالجانب البايوميكانيكي من قبل المدربين والتأكيد على وضع القوة
This paper concerns the peristaltic flow of a Williamson fluid with variable viscosity model through porous medium under combined effects of MHD and wall properties. The assumptions of Reynolds number and long wavelength is investigated. The flow is investigated in a wave frame of reference moving with velocity of the wave. The perturbation series in terms of the Weissenberg number (We <1) was used to obtain explicit forms for velocity field and stream function. The effects of thermal conductivity, Grashof number, Darcy number, magnet, rigidity, stiffness of the wall and viscous damping force parameters on velocity and stream function have been studied.
The formula of Ijarah and Ijarah ending with ownership is one of the investment formulas in Islamic banks, so this research has shed light on it in order to benefit from the experiences of the research sample banks, This research aims to find a reliable way for Iraqi Islamic banks, namely (leasing and leasing ending with ownership) in order to invest their money without usurious interests, The problem of the research emerges through the lack of awareness of the Iraqi Islamic banks to work with different Islamic financing formulas and their inability to invest their money through the adoption of their administrations for different formulas, including the leasing, and this is reflected in the decrease and fluctuation of its profits, Theref
... Show Moremixtures of cyclohexane + n-decane and cyclohexane + 1-pentanol have been measured at 298.15, 308.15, 318.15, and 328.15 K over the whole mole fraction range. From these results, excess molar volumes, VE , have been calculated and fitted to the Flory equations. The VE values are negative and positive over the whole mole fraction range and at all temperatures. The excess refractive indices nE and excess viscosities ?E have been calculated from experimental refractive indices and viscosity measurements at different temperature and fitted to the mixing rules equations and Heric – Coursey equation respectively to predict theoretical refractive indices, we found good agreement between them for binary mixtures in this study. The variation of th
... Show MoreIn this paper, variable gain nonlinear PD and PI fuzzy logic controllers are designed and the effect of the variable gain characteristic of these controllers is analyzed to show its contribution in enhancing the performance of the closed loop system over a conventional linear PID controller. Simulation results and time domain performance characteristics show how these fuzzy controllers outperform the conventional PID controller when used to control a nonlinear plant and a plant that has time delay.
A new mode of methodology was adopted in the assay of PM- HCL based on the use of water crystal gel bead made of poly acrylic acid in which the gel beads were left to absorbe persulphate solution that is necessary for the oxidation of PM- HCL in aqua media . The water crystal act as a reserviour for S2O82- . Optimum parameters were studied giving to specify the chemical and physical parameters. Two line manifold was used .The flow rates of 1.5 and 1.2 ml.min-1 was used , 3 gel beads , 120 μL sample volume , a linear dynamic range extend from 0.01- 18 mmol.L-1. A correlation coefficient (r) of 0.9991while the percentage linearity (r2%) of 99.82% with R.S.D% at 8 mmol.L-1 promethazine-HCl is less than 0.5% (ten replicates) and a detection
... Show MoreThis article presents a new cascaded extended state observer (CESO)-based sliding-mode control (SMC) for an underactuated flexible joint robot (FJR). The control of the FJR has many challenges, including coupling, underactuation, nonlinearity, uncertainties and external disturbances, and the noise amplification especially in the high-order systems. The proposed control integrates the CESO and SMC, in which the CESO estimates the states and disturbances, and the SMC provides the system robustness to the uncertainty and disturbance estimation errors. First, a dynamic model of the FJR is derived and converted from an underactuated form to a canonical form via the Olfati transformation and a flatness approach, which reduces the complexity of th
... Show MoreThis paper aims to study the second-order geometric nonlinearity effects of P-Delta on the dynamic response of tall reinforced concrete buildings due to a wide range of earthquake ground motion forces, including minor earthquake up to moderate and strong earthquakes. The frequency domain dynamic analysis procedure was used for response assessment. Reinforced concrete building models with different heights up to 50 stories were analyzed. The finite element software ETABS (version 16.0.3) was used to analyze reinforced concrete building models.
The study reveals that the percentage increase in buildings' sway and drift due to P-Delta effects are nearly constant for specific building height irrespective of the seism
... Show MoreBackground: Dental erosion is a common oral condition which results due to consumption of high caloric and low pH acidic food such as carbonated drinks and fruit juices. It is expected that these food types can cause irreversible damage to dental hard tissues and early deterioration of the dental restorations. So, this study aimed to evaluate and compare the erosive potential effects of orange fruit juice and Miranda orange drink on the microhardness of an orthodontic composite material. Materials and methods: Thirty discs with a thickness of 2 mm and a diameter of 10 mm were prepared from orthodontic bonding composite. The prepared discs were equally divided into three groups (n=10). Microhardness analysis was carried out both prior to
... Show MoreMagnesium oxide nanoparticles (MgO NPs) were synthesized by a green method using the peels of Persimmon extract as the reducing agent , magnesium nitrate, and NaOH. This method is eco-friendly and non-toxic. In this study, an ultrasound device was used to reduce the particle size, with the impact on the energy gap was set at the beginning at 5.39 eV and then turned to 4.10 eV. The morphological analysis using atomic force microscopy (AFM) showed that the grain size for MgO NPs was 67.70 nm which became 42.33 nm after the use of the ultrasound. The shape of the particles was almost spherical and became cylindrical. In addition the Field-Emission Scanning Electron Microscopy (FESEM) analysis sh
... Show MoreThe study aimed to reveal the degree of inclusion of media concepts in the books of social and national studies in general education in light of the criteria of media education and the nature of the Saudi society. Additionally, to identify the estimations of the participants in the study of the importance of including media concepts in these books, and to build a matrix of the range and sequence of media concepts in the books of social and national studies in the grades of Saudi general education. The study followed the descriptive approach in both descriptive analysis of the textbooks and descriptive survey of the study participants who were (203) students in the schools of boys and girls in general education in Makkah. The study used t
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