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 research worked on identifying the effect of increasing the volume of indebtedness by companies listed on the Iraq Stock Exchange on the trading volume of those companies, and this research included some theoretical concepts related to both debt financing and trading volume, and it represents the research community of the joint-stock companies listed in The Iraq Stock Exchange (the banking sector). As for the research sample, it was deliberately chosen represented by companies with continuous trading without stopping, which reached 10 joint-stock companies, and the period of research was extended during the period 2011-2015, and a set of indicators and financial methods were used In measuring research v
... Show MoreThe aim of this work is to learn the relationship of the stability of (β) emitter isobars with their shape for some isobaric elements with even mass number (A=152 - 162). To reach this goal firstly the most stable isobar have been determined by plotting mass parabola (plotting the binding energy (B.E) as a function of the atomic number (Z)) for each isobaric family. Then three-dimensional representation graphics for each nucleus in these isobaric families have been plotted to illustrate the deformation in the shape of a nucleus. These three-dimensional representation graphics prepared by calculating the values of semi-axis minor (a), major (b) and (c) ellipsoid axis’s. Our results show that the shape of nuclides which is represented the
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In this study, optical fibers were designed and implemented as a chemical sensor based on surface plasmon resonance (SPR) to estimate the age of the oil used in electrical transformers. The study depends on the refractive indices of the oil. The sensor was created by embedding the center portion of the optical fiber in a resin block, followed by polishing, and tapering to create the optical fiber sensor. The tapering time was 50 min. The multi-mode optical fiber was coated with 60 nm thickness gold metal. The deposition length was 4 cm. The sensor's resonance wavelength was 415 nm. The primary sensor parameters were calculated, including sensitivity (6.25), signal-to-noise ratio (2.38), figure of merit (4.88), and accuracy (3.2)
... Show MorePhotonic Crystal Fiber Fabry–Perot Interferometers (FPI) based on Surface Plasmon Resonance (SPR) was investigated in this paper in order to detect changes in photonic crystal fiber sensitivity with increasing temperature. FPI is composed of a PCF (ESM-12) solid core spliced with a single-mode fiber (SMF) on one side and a 40nm thick gold Nano film on the other. In order to obtain the SPR curve, the end of PCF can be spliced with the side of SMF before covering the gold film on the PCF. SPR results are included in the suggested sensor, based on the conclusions of the investigations. Resolution (R) is 0.0871, Signal-to-Noise Ratio (SNR) is 0.1867, a figure of merit (FOM) is 0.0069, and sensitivity (S) is 1.1481 . This sensor proposed is s
... Show MoreThe Backstepping Sliding Mode Control is a control technique used for controlling nonlinear systems. In this paper, the performance of the backstepping sliding mode controller schemes for the angular velocity control for a rotary actuator of an angular velocity control system that utilizes a novel hydraulic flow control method called inlet throttling was investigated. For the angular velocity dynamic, a linear state feedback with suitable high gain is designed as the virtual controller, where steady state error can be made arbitrarily small according to the gain value. A time varying sliding variable is then selected based on the designed virtual controller. The resulting control design is robust, and the maximum error of the angular veloci
... Show MoreIn this paper, a robust adaptive sliding mode controller is designed for a mobile platform trajectory tracking. The mobile platform is an example of a nonholonomic mechanical system. The presence of holonomic constraints reduces the number of degree of freedom that represents the system model, while the nonholonomic constraints reduce the differentiable degree of freedom. The mathematical model was derived here for the mobile platform, considering the existence of one holonomic and two nonholonomic constraints imposed on system dynamics. The partial feedback linearization method was used to get the input-output relation, where the output is the error functions between the position of a certain point on the platform
... Show MoreFluid-structure interaction method is performed to predict the dynamic characteristics of axial fan system. A fluid-structure interface physical environment method (monolithic method) is used to couple the fluid flow solver with the structural solver. The integration of the three-dimensional Navier-Stokes equations is performed in the time Doman, simultaneously to the integration of the three dimensional structural model. The aerodynamic loads are transfer from the flow to structure and the coupling step is repeated within each time step, until the flow solution and the structural solution have converged to yield a coupled solution of the aeroelastic set of equations. Finite element method is applied to solve numerically
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One of the major components in an automobile engine is the throttle valve part. It is used to keep up with emissions and fuel efficiency low. Design a control system to the throttle valve is newly common requirement trend in automotive technology. The non-smoothness nonlinearity in throttle valve model are due to the friction model and the nonlinear spring, the uncertainty in system parameters and non-satisfying the matching condition are the main obstacles when designing a throttle plate controller.
In this work, the theory of the Integral Sliding Mode Control (ISMC) is utilized to design a robust controller for the Electronic Throttle Valve (ETV) system. From the first in
... 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 MoreUsing the Internet, nothing is secure and as we are in need of means of protecting our data, the use of passwords has become important in the electronic world. To ensure that there is no hacking and to protect the database that contains important information such as the ID card and banking information, the proposed system stores the username after hashing it using the 256 hash algorithm and strong passwords are saved to repel attackers using one of two methods: -The first method is to add a random salt to the password using the CSPRNG algorithm, then hash it using hash 256 and store it on the website. -The second method is to use the PBKDF2 algorithm, which salts the passwords and extends them (deriving the password) before being ha
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