أن كرة السلة بما تتضمنه من مهارات حركية متنوعة تتطلب من ممارسيها امتلاك عدد من القدرات الحركية الخاصة وبشكل خاص التوافق العضلي العصبي والرشاقة والقوة المميزة بالسرعة، فضلاعن قدرات الإدراك الحس- حركي (إدراك المكان وقوة دفع الكرة سواء بالطبطبة العالية أو الواطئة .... الخ ) لذا تكمن أهمية البحث في إيجاد الطرق والوسائل التي تطور قدرة الطالبة على إدراك قوة دفع الكرة والإحساس بها أثناء تعلم وتدريب الطبطبة بأنواعها بإدخال تمرينات إدراك قوة الذراع ومن ثم تأثيرها على مستوى أداء مهارة الطبطبة في كرة السلة . ومن خلال ملاحظة أداء الطالبات في دروس كرة السلة وجدنا ضعف في أداء مهارة الطبطبة سواء كان من الثبات أو من الحركة وعدم إدراك القوة اللازمة لأداء هذه المهارة بصورة صحيحة مما يؤدي إلى ارتباك في الأداء, ويدفع الطالبة إلى إعطاء قوة غير مناسبة وبالتالي ارتفاع الكرة إثناء الطبطبة إلى أعلى من مستوى الحوض أو إعطاء قوة غير كافية مما يؤدي انخفاض مستوى الطبطبة ، وهذا يرجع إلى قلة الإدراك والإحساس بالقوة المناسبة لدفع الكرة ، وهنا تكمن مشكلة البحث. وهدفت الدراسة إلى معرفة تأثير تمرينات إدراك قوة الذراع على مستوى أداء مهارة الطبطبة في كرة السلة . استخدم المنهج التجريبي على طالبات المرحلة الرابعة البالغ عددهم (25) طالبة قسموا على مجموعتين ( تجريبية وضابطة ) طبقت التجريبية تمرينات إدراك قوة الذراع , خلال الطبطبة (دفع الكرة) أدخلت في القسم الرئيسي الجانب التطبيقي من الدرس وبواقع ( 10 ) دقائق وعلى مدى 8 أسابيع . فاستنتج أن لتدريبات إدراك قوة الذراع تأثيراً ايجابياً في تطوير مهارة الطبطبة في كرة السلة لدى إفراد عينة البحث. وتوصي الباحثات بالتركيز على التمارين خاصة بادراك قوة الذراع خلال الدرس للارتقاء بمستوى أداء المهارة .
The aim of this research is to employ starch as a stabilizing and reducing agent in the production of CdS nanoparticles with less environmental risk, easy scaling, stability, economical feasibility, and suitability for large-scale production. Nanoparticles of CdS have been successfully produced by employing starch as a reducing agent in a simple green synthesis technique and then doped with Sn in certain proportions (1%, 2%, 3%, 4%, and 5%).According to the XRD data, the samples were crystallized in a hexagonal pattern, because the average crystal size of pure CdS is 5.6nm and fluctuates in response to the changes in doping concentration 1, 2, 3, 4, 5 %wt Sn, to become 4.8, 3.9, 11.5, 13.1, 9.3 nm respectively. An increase in crystal
... Show MoreUpper limb amputation is a condition that severely limits the amputee’s movement. Patients who have lost the use of one or more of their upper extremities have difficulty performing activities of daily living. To help improve the control of upper limb prosthesis with pattern recognition, non-invasive approaches (EEG and EMG signals) is proposed in this paper and are integrated with machine learning techniques to recognize the upper-limb motions of subjects. EMG and EEG signals are combined, and five features are utilized to classify seven hand movements such as (wrist flexion (WF), outward part of the wrist (WE), hand open (HO), hand close (HC), pronation (PRO), supination (SUP), and rest (RST)). Experiments demonstrate that usin
... Show MoreRealistic implementation of nanofluids in subsurface projects including carbon geosequestration and enhanced oil recovery requires full understanding of nanoparticles (NPs) adsorption behaviour in the porous media. The physicochemical interactions between NPs and between the NP and the porous media grain surface control the adsorption behavior of NPs. This study investigates the reversible and irreversible adsorption of silica NPs onto oil-wet and water-wet carbonate surfaces at reservoir conditions. Each carbonate sample was treated with different concentrations of silica nanofluid to investigate NP adsorption in terms of nanoparticles initial size and hydrophobicity at different temperatures, and pressures. Aggregation behaviour and the
... Show MoreThe temperature control process of electric heating furnace (EHF) systems is a quite difficult and changeable task owing to non-linearity, time delay, time-varying parameters, and the harsh environment of the furnace. In this paper, a robust temperature control scheme for an EHF system is developed using an adaptive active disturbance rejection control (AADRC) technique with a continuous sliding-mode based component. First, a comprehensive dynamic model is established by using convection laws, in which the EHF systems can be characterized as an uncertain second order system. Second, an adaptive extended state observer (AESO) is utilized to estimate the states of the EHF system and total disturbances, in which the observer gains are updated
... Show MoreThis study aims to fabricate and assess the β-tricalcium phosphate (β-TCP) bioactive ceramic coat layer on bioinert ceramic zirconia implants through the direct laser melting technique by applying a long-pulsed Nd:YAG laser of 1064 nm. Surface morphologies, adherence, and structural change in the coatings were evaluated by optical microscopy, field emission scanning electron microscope, hardness, and x-ray diffractometer. The elastic modulus (EM) of the coating was also determined using the nanoindentation test. The quality of the coating was improved when the laser power was 90 W with a decrease in the scan speed to 4 mm s−1. The chemical composition of the coat was maintained after laser processing; also, the Energy Dispersive
... Show MoreNew, simple and sensitive batch and Flow-injecton spectrophotometric methods for the determination of Thymol in pure form and in mouth wash preparations have been proposed in this study. These methods were based on a diazotization and coupling reaction between Thymol and diazotized procaine HCl in alkaline medium to form an intense orange-red water-soluble dye that is stable and has a maximum absorption at 474 nm. A graphs of absorbance versus concentration show that Beer’s law is obeyed over the concentration range of 0.4-4.8 and 4-80 µg.ml-1 of Thymol, with detection limits of 0.072 and 1.807 µg.ml-1 of Thymol for batch and FIA methods respectively. The FIA procedure sample throughput was 80 h-1. All different chemical and physical e
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