An analytical study of the crossing and throwing steps and the distances of pulling and extending the arm of elite javelin throwers and their relationship to achieve menthe researcherAbstract : The javelin throw event is one of the distinguished events in athletics, and it requires physical capabilities and special movement capabilities in addition to some physical specifications. Approximate or final throwing phase.The importance of research is highlighted by the continuous interest in sports achievements and the continuation of the process of developing them, and the importance of kinetic analysis in revealing the most important weaknesses of shooters, and the importance of biomechanical variables, especially the last throwing steps, the distance of withdrawal and the extension of the throwing arm during the throwing.The research problem revolved around the importance of identifying some numerical values of the biomechanical variables and their relationship to achievement, focusing on the weaknesses that the Iraqi spear thrower suffers from in the pre-throwing stage of force preparation, and working on analyzing these molecules and applying them to improve technical performance.And the failure to use motor analysis and identify weaknesses with high accuracy, in addition to the lack of interest by the trainers in the characteristics of the values of the biomechanical variables affecting each other in order to program their training programs in order to achieve their goals as quickly as possible and with the least effort.The aim of the research is to identify the most important biomechanical variables related to the stage of preparing the force, which is the speed of the last throwing step and the speed of the penultimate scissor crossing step and the decrease between the speed of these two steps and the distance of pulling and extending the throwing arm and the relationship between these variables with the achievement of the Iraqi elite spear throwers.The researcher used the descriptive approach and correlational relationships in her current study because it is appropriate to the nature of the problem of the study. The research community consisted of elite Iraqi players who are advanced in javelin throwing, and their number is (6) shooters. They took a comprehensive enumeration method. The test was conducted on the research sample in the stadium of the College of Physical Education and Sports Sciences / University of Kufa in preparation for the championship. The Iraqi clubs have the third round, giving each shooter six attempts as in the official races, and the best attempt was taken as an achievement for the analysis, and two analysis cameras (CASIO FH13.5) were used at a speed of 120 frames per second, and the analysis was done with the analysis program (Kenova). After analyzing and discussing the results, the researcher concluded that there is a relationship A direct correlation between the length and speed and the distance of the throwing arm with the achievement and an inverse correlation between the steps and the time of the steps and the difference between the two speeds and the distance of the stretch with the achievement.
A field experiment was carried out during the spring season 2019 and 2020 to obtain a fast, uniform, and high field emergence ratio of maize seeds under a wide range of environmental conditions. Randomize complete block design in the split-plot arrangement was used with three replications. The first factor in the main plots was cultivars (5018, Baghdad3 and Sumer). The second factor in the sub-plots was seeds soaking with ascorbic and citric acids (100 mg L−1) each and humic (1 ml L−1) in addition to control treatment (seeds soaking with distilled water only). Results showed the superiority of soaking with humic acid significantly, as means of characteristics of field emergence in both seasons, respectively, were as follows: Last day of
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The aim of the current research is to identify the personal distance between members of society, as well as, to identify the feelings of satisfaction and positivity from respecting the permissible personal distance. The study also aims to identify the feelings of annoyance and comfort from approaching and going beyond personal distance and not respecting it. To achieve these goals, the researchers reviewed previous literature, theories, and studies that dealt with personal distance. The researchers reached a number of results; first, personal distance is not a law but rather a cultural guiding principle for social and professional morals. Second, there are four distances (intimate distance, the distance between friends, social distance,
... Show MoreWith simple and undirected connected graph Φ, the Schultz and modified Schultz polynomials are defined as and , respectively, where the summation is taken over all unordered pairs of distinct vertices in V(Φ), where V(Φ) is the vertex set of Φ, degu is the degree of vertex u and d(v,u) is the ordinary distance between v and u, u≠v. In this study, the Shultz distance, modified Schultz distance, the polynomial, index, and average for both have been generalized, and this generalization has been applied to some special graphs.
In this study, an approach inspired by a standardized calibration method was used to test a laser distance meter (LDM). A laser distance sensor (LDS) was tested with respect to an LDM and then a statistical indicator explained that the former functions in a similar manner as the latter. Also, regression terms were used to estimate the additive error and scale the correction of the sensors. The specified distance was divided into several parts with percent of longest one and observed using two sensors, left and right. These sensors were evaluated by using the regression between the measured and the reference values. The results were computed using MINITAB 17 package software and excel office package. The accuracy of the results in this wo
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In this study the simple pullout concrete cylinder specimen reinforced by a single steel bar was analyzed for bond-slip behavior. Three-dimension nonlinear finite element model using ANSYS program was employed to study the behavior of bond between concrete and plain steel reinforcement. The ANSYS model includes eight-noded isoperimetric brick element (SOLID65) to model the concrete cylinder while the steel reinforcing bar was modeled as a truss member (LINK8). Interface element (CONTAC52) was used in this analysis to model the bond between concrete and steel bar. Material nonlinearity due to cracking and/or crushing of concrete, and yielding of the steel reinforcing bar were taken into consideration during the analysis. The accuracy of this
... Show MoreMany organizations today are interesting to implementing lean manufacturing principles that should enable them to eliminating the wastes to reducing a manufacturing lead time. This paper concentrates on increasing the competitive level of the company in globalization markets and improving of the productivity by reducing the manufacturing lead time. This will be by using the main tool of lean manufacturing which is value stream mapping (VSM) to identifying all the activities of manufacturing process (value and non-value added activities) to reducing elimination of wastes (non-value added activities) by converting a manufacturing system to pull instead of push by applying some of pull system strategies a
... Show MoreIn this study the simple pullout concrete cylinder specimen reinforced by a single steel bar was analyzed for bond-slip behavior. Three-dimension nonlinear finite element model using ANSYS program was employed to study the behavior of bond between concrete and plain steel reinforcement. The ANSYS model includes eight-noded isoperimetric brick element (SOLID65) to model the concrete cylinder while the steel reinforcing bar was modeled as a truss member (LINK8). Interface element (CONTAC52) was used in this analysis to model the bond between concrete and steel bar. Material nonlinearity due to cracking and/or crushing of concrete, and yielding of the steel reinforcing bar were taken into consideration during the analysis. The accuracy of t
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The current study aims to examine the level of problems faced by university students in distance learning, in addition to identify the differences in these problems in terms of the availability of internet services, gender, college, GPA, interactions, academic cohort, and family economic status. The study sample consisted of (3172) students (57.3% females). The researchers developed a questionnaire with (32) items to measure distance learning problems in four areas: Psychological (9 items), academic (10 items), technological (7 items), and study environment (6 items). The responses are scored on a (5) point Likert Scale ranging from 1 (strongly disagree) to 5 (strongly agree). Means, standard deviations, and Multivariate Analysis of Vari
... Show MoreLet be any connected graph with vertices set and edges set . For any two distinct vertices and , the detour distance between and which is denoted by is a longest path between and in a graph . The detour polynomial of a connected graph is denoted by ; and is defined by . In this paper, the detour polynomial of the theta graph and the uniform theta graph will be computed.
In this article, the backstepping control scheme is proposed to stabilize the fractional order Riccati matrix differential equation with retarded arguments in which the fractional derivative is presented using Caputo's definition of fractional derivative. The results are established using Mittag-Leffler stability. The fractional Lyapunov function is defined at each stage and the negativity of an overall fractional Lyapunov function is ensured by the proper selection of the control law. Numerical simulation has been used to demonstrate the effectiveness of the proposed control scheme for stabilizing such type of Riccati matrix differential equations.
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