تعد الرماية واحدة من الألعاب التي يقاس مستوى الانجاز فيها بالأرقام إذ ارتفعت الأرقام المسجلة بالنسبة لسلاح المسدس الهوائي حتى وصلت عند بعض الأبطال العالميين إلى الانجاز النهائي ، وقد لجأ المدربون إلى مختلف الطرق التدريبية, وان ضعف الثبات والتركيز هما اللذان يقودان إلى هبوط مستوى الانجاز في الرماية ، ولتحقيق التركيز والثبات المطلوبين أثناء الرمي يجب التدريب على مطاولة حمل السلاح التي تعد من أصعب تدريبات الرماية لما تحتاجه من صبر وقوة تحمل لفترة طويلة نسبياً ، والثبات ممكن أن يزول بوجود أي مؤثر خارجي أو داخلي قد يتعرض له الرامي كالأحوال الجوية المفاجئة إذا كان ميدان الرمي مفتوحاً أو تعرض الرامي إلى أي ضغط نفسي أو شد عضلي نتيجة التوتر والضغط ، ولمعالجة هذه الظروف لدى اللاعب اتجه المدربون إلى العمل على تهدئــة اللاعبيــن قبل البدء بالســباق أوالتدريـب على الرمي وذلك باستعمال وسائل متعـددة ومنــها بعض الأدويــة المهدئـــة وقســــم منها يدخــل ضمن قائمة (المنشطات المحظورة ) ويطلق عليهـا ( المهدئات ) إذ تعمل المهدئات على منع توتر اللاعب والتخفيف من الضغط النفسي والعصبي الذي يتعرض له نتيجة جو السباق أو ما يسمى حمى البداية التي قد تصيب بعض اللاعبين أو اغلبهم لعدم خوضهم عدد كافٍ من السباقات أو قلة الخبرة وبالتالي يفقد التركيز والثبات اللذين هما الركيزتان الأساسيتان للرمي أثناء السباق ، وتعمل المهدئات في هذه الحالة على تخفيف توتر اللاعب وبالتالي الرمي بثبات وهدوء وتحقيق الانجاز الأفضل, ولكن تبقى هذه الطرق غير قانونية ومحاطة بالمخاطر ، كما استعمل بعض المدربون مركبات أخرى للوصول إلى حالة الثبات غير المهدئات وهي الأدوية والمركبات التي تعمل على خفض نشاط القلب والدورة الدموية وتخفيف الضغط الدموي وتخفيف سرعة نبض القلب مما يساعد على التهدئة والثبات ، ولكن هذه الأدويــة ( كدواء الاتينولول ) ( ) يستخدم في علاج الضغط الدموي المرتفع وهو من الأدوية المحظورة التي تستخدم تحت ضوابط معينة .
I mpact strength for Epoxy/Polyurethane, Blends and their composites with two
layers of Glass fibers (0-90) are calculated.
The impact strength of the blends and composites decrease with increasing weight
by weisht percentage of polyurethane . This result is attributed to the high elasticity
of PU , and to the immiscibility between the polymer blends as well as the fiber
delaminates
Iraqi EFL college instructors, who supervise the teaching practice of EFL student teachers, commonly experience the inefficient teaching performance of prospective teachers. This inefficiency is usually due to their inability to make connections between the practical experience and the theoretical knowledge of TEFL. One of the reasons behind this inability may be the employment of traditional ways of training and instructing student teachers. Moreover, it is usually noticed that many Iraqi EFL student teachers have a negative attitude toward the teaching profession. They explicitly state that they would join the teaching force only if they fail to work in any other field.
... Show MoreIn this work, two graphene oxide (GO) samples were prepared using the Hummers method with graphite (g) and KMnO4 (g) ratios of 1:3 (GO3) and 1:6 (GO6). The effect of oxidation degree on the structural, electrical, and dielectric properties of the GO samples was investigated. The structures of the GO samples were studied using various techniques, including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDXS). XRD analysis revealed an increase in the interlayer spacing and a decrease in the number of layers of the samples with increasing oxidant content. The two GO samples have giant permittivity values of ~105 in the low-frequency
... Show MoreAbstract:
Since the railway transport sector is very important in many countries of the world, we have tried through this research to study the production function of this sector and to indicate the level of productivity under which it operates.
It was found through the estimation and analysis of the production function Kub - Duglas that the railway transport sector in Iraq suffers from a decline in the level of productivity, which was reflected in the deterioration of the level of services provided for the transport of passengers and goods. This led to the loss of the sector of importance in supporting the national economy and the reluctance of most passengers an
... Show MoreChilled ceilings systems offer potential for overall capital savings. The main aim of the present research is to investigate the thermal performance of the indirect contact closed circuit cooling tower, ICCCCT used with chilled ceiling, to gain a deeper knowledge in this important field of engineering which has been traditionally used in various industrial & HVAC systems. To achieve this study, experimental work were implemented for the ICCCCT use with chilled ceiling. In this study the thermal performances of closed wet cooling tower use with chilled ceiling is experimentally and theoretically investigated. Different experimental tests were conducted by varying the controlling parameters to investigate their effects
... Show MoreBackground: Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60
... Show MoreNitrogen (N) is a key growth and yield-limiting factor in cultivated rice areas. This study has been conducted to evaluate the effects of different conditions of N application on rice yield and yield components (Shiroudi cultivar) in Babol (Mazandaran, Iran) during the 2015- 2016 season. A factorial experiment executed of a Randomized Complete Block Design (RCBD) used in three iterations. In the first factor, treatments were four N amounts (including 50, 90, 130, and 170 kg N ha-1), while in the second factor, the treatments consisted of four different fertilizer splitting methods, including T1:70 % at the basal stage + 30 % at the maximum tillering stage, T2:1/3 at the basal stage + 1/3 at the maximum ti
... Show MoreBackground: Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60
... Show MoreDental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60 test block w
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