يشهد العالم تقدما في كافة مجالات الحياة المختلفة وتزداد الحياة صعوبة يوما بعد يوم, ويزداد البحث في كافة المجالات التي تعمل على خدمة الإنسان ولقد طال هذا التقدم النشاط الرياضي ,فقد يكون لتطور التدريب الرياضي وتنوع أساليبه الدور الكبير في تحقيق اللياقة البدنية التي تعد إحدى أهم الأهداف التي يرمي إليها الدرس في كلية التربية الرياضية . واللياقة البدنية تستمد أهميتها من كونها إحدى مكونات اللياقة الشاملة التي بدورها تؤهل الفرد للعيش بصورة متزنة وهذا يتطلب أن يكون الفرد مؤهلا جسميا ونفسيا وعقليا, وتأتي أهمية اللياقة البدنية من خلال ارتباطها بمتطلبات الحياة اليومية من جهة وممارسة الأنشطة الرياضية من جهة أخرى ،ولا يغفل علينا بان الدراسة في كلية التربية الرياضية تجمع بين الدراستين النظرية والعملية ، وان الطابع العملي يمثل جزءا كبيرا من الدروس الأكاديمية للألعاب الرياضية التي يتلقاها الطلاب على مدار السنوات الأربع ، وهذه الخصوصية تفرض سلوكيات ومواقف تنافسية مختلفة على أساس اختلاف الدروس العملية . وعليه تبرز المتطلبات البدنية من بين العديد من المتطلبات التي يحتاجها الطالب لاجتياز المقررات المهارية في هذه الكلية. وهنا تكمن مشكلة البحث إذ نجد المدرس والطالب يركزان على التعلم المهاري وإهمال الجانب البدني لان الركيزة الأساسية للدرس هو تعلم المهارات للفعالية , لذا وجد درس اللياقة البدنية من بين الدروس العملية لتطوير المستوى البدني للطلبة , وأن التحصيل العملي المهاري كأي متغير تابع يتأثر بمدى امتلاك الطالب للقدرات المختلفة كاللياقة البدنية ، إضافة إلى الإمكانات الجسمية ، وكل هذه القدرات تتداخل فيما بينها لتعطي أداء وانجازاً مهارياً عالياً في أي فعالية رياضية .
Recycling process presents a sustainable pavement by using the old materials that could be milled, mixed with virgin materials and recycling agents to produce recycled mixtures. The objective of this study is to evaluate the impact of water on recycled asphalt concrete mixtures, and the effect of the inclusion of old materials into recycled mixtures on the resistance of water damage. A total of 54 Marshall Specimens and 54 compressive strength specimens of (virgin, recycled, and aged asphalt concrete mixtures) had been prepared, and subjected to Tensile Strength Ratio test, and Index of Retained Strength test. Four types of recycling agents (used oil, oil + crumb rubber, soft grade asphalt cement, and asphalt cement + Su
... Show MoreSoil-structure frictional resistance is an important parameter in the design of many foundation systems. The soil-structure interface area is responsible for load transferring from the structure to the surrounding soil. The mobilized shaft resistance of axially loaded, long slender pile embedded in dense, dry sand is experimentally and numerically analyzed when subjected to pullout force. Experimental setup including an instrumented model pile while the finite element method is used as a numerical analysis tool. The hypoplasticity model is used to model the soil adjacent to and surrounding the pile by using ABAQUS FEA (6.17.1). The soil-structure interface behavior depends on many factors, but mainly on the interface soi
... Show MoreThe crystalline zeolite, namely faujasite type Y with SiO2/Al2O3 mole ratio of 5 was used as raw material for preparation of isomerization catalysts. A 0.5 wt % Pt/HY-zeolite catalyst was prepared by impregnation of the decationized HY-zeolite with chloroplatinic acid. The dectionized HY-zeolite was treated with HCl, HNO3 and HI promoters using different normalities and with different concentrations of Sn, Ni and Ti promoters by impregnation method to obtain acidic and metallic promoters' catalysts, respectively. A 0.5 wt% of Pt was added to above catalysts using impregnation method. Isomerization of n-hexane was carried out at different prepared catalysts. The isomerization temperature varied from 250–325° C over weight hourly space
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The paper is concerned with, the behavior of the hydrostatic thrust bearings lubricated with liquid-solid lubricants using Einstein viscosity formula, and taking into account the centrifugal force resulting from high speed. Also studied is the effect of the bearing dimensions on the pressure, flow rate, load capacity, shear stress, power consumption and stiffness.
The theoretical results show an increase in load capacity by (8.3%) in the presence of solid graphite particles with concentration of (16%) by weight as compared with pure oil, with increasing shear stress. .
In general the performance of hydrostatic thrust bearings improve for load carrying capacity, volume flow rate,
... Show MoreThis research studying the phenomenon of Doppler (frequency Doppler) as a method through which the direction and speed of the blood cells flows in blood vessels wear measured. This Doppler frequency is relied upon in medicine for measuring the speed of blood flow, because the blood flow is an important concept from the concepts of medicine. It represents the function and efficient of the heart and blood vessels in the body so any defect in this function will appear as a change in the speed of blood flow from the normal value assumed. As this speed changes alot in cases of disease and morbidity of the heart, so in order to identify the effect of changing the Doppler frequency on the speed of blood flow and the relationship of
... Show MoreTwilight is that light appear on the horizon before sunrise and after sunset, Astronomically it is known that sunrise and sunset are effected by high above sea level, but the effect of high above sea level on the time of astronomical twilight still not decided and controversy among astronomers, in This research we studies the effect of high above sea level on the time of astronomical twilight, through adding the equation correct high above sea level to equation computation of twilight and then calculate of changing in the time of twilight for different highest (0-10000) meters above sea level , and the ratio of increase for time with high between (15.45-20.5) minutes. It was found that there was an increase in the time of the twilight along
... Show MoreMR Younus, Nasaq Journal, 2022
The purpose of this paper is to depict the effect of adding a hydraulic accumulator to a hydraulic system. The experimental work includes using measuring devices with interface to measure the pressure and the vibration of the system directly by computer so as to show the effect of accumulator graphically for real conditions, also the effects of hydraulic accumulator for different applications
have been tested. A simulation analysis of the hydraulic control system using MATLAB.R2010b to study was made to study the stability of the system depending on the transfer function, to estimate the effect of adding the accumulator on stability of the system. A physical simulation test was made for the hydraulic system using MATLAB to show the ef