The research problem lies in: The use of positive and negative flexibility exercises to develop the special strength of the 400m hurdles player, that some young people face weakness and a problem in performance, which requires the need to prepare special exercises for physical and skill numbers using the types of exercises that have resilient strength, flexibility and have the effect on developing and determining the level of physical and skill performance. To develop 400m hurdles, special strength, explosive power and the characteristic velocity of arms and legs. Research aims: 1. Preparing positive and negative flexibility exercises to develop the special force and the effectiveness of 400m youth barriers. 2. Identify the effect of exercises on the development of special strength and the effectiveness of 400m youth barriers. The researcher used the experimental approach, where the research community consisted of players in the 400m youth hurdles event, which numbered (6) for the year 2018-2019. Positive and negative flexibility exercises prepared by the researcher were used. The researcher concluded: The positive and negative flexibility exercises had a positive effect on the development of the special strength of arms and legs and the results of the effectiveness of 400m youth barriers. The researcher recommends: taking the results of this study and circulating it, and emphasizing on equipping the playgrounds with modern training methods, due to the positive impact it achieves on physical development.
Broyden update is one of the one-rank updates which solves the unconstrained optimization problem but this update does not guarantee the positive definite and the symmetric property of Hessian matrix.
In this paper the guarantee of positive definite and symmetric property for the Hessian matrix will be established by updating the vector which represents the difference between the next gradient and the current gradient of the objective function assumed to be twice continuous and differentiable .Numerical results are reported to compare the proposed method with the Broyden method under standard problems.
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In this work polymeric composites were done from unsaturated polyester as a matrix reinforced with glass fiber type (E-glass) with two different volume fraction 20% & 40%. Fatigue tests showed that the number of fatigue cycles to failure limit for samples reinforced with uniform (woven Roving 0-90°) E-glass fiber and random (continuous fibers) with volume fraction 40% more than that for the same samples with volume fraction 20%. Also the fatigue results showed that the uniform samples failed with fatigue cycles more than that of random.
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This investigation aimed to explain the mechanism of MFCA by applying this method on air-cooled engine factory which was suffering from high production cost. The results of this study revealed that MFCA is a useful tool to identify losses and inefficiencies of the production process. It is found that the factory is suffering from high losses due to material energy and system losses. In conclusion, it is calculated that system losses are the highest among all the losses due to inefficient use of available production capacity.
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The present research was conducted to investigate the effectiveness of a training program to improve some aspects of sensory integration disorder and its effect on self-direction among a sample of children with intellectual disabilities. The study sample consists of (10 subjects as an experimental group) were exposed to the training program، and the control group consists of (10 subjects as a control group) were not exposed to the training program. The study included the following tools: A scale of self-direction for intellectual disability (prepared by the researcher). Training program (prepared by the researcher). The Results of the study showed the following: There are no statistically significant differences between the means ranks
... Show MoreThe research aimed to identify the level of job security, the level of sports institutional performance, and the relationship, contribution and impact of job security to sports institutional performance from the point of view of workers in the Iraqi Ministry of Youth and Sports. The descriptive approach was adopted in the manner of correlational relationships on a sample of (400) individuals who were randomly selected by (33.333%) of the employees working in the institutions at the headquarters of the Ministry of Youth and Sports, amounting to a total of (2293) individuals for the sports season (2022-2023), and they are naturally distributed among (13) main institutions in the formations of the headquarters of this ministry, and after adopt
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