scholarly journals Kinematic Analysis of Volleyball Attack in the Net Center with Various Types of Take-Off

2017 ◽  
Vol 58 (1) ◽  
pp. 261-271 ◽  
Author(s):  
František Zahálka ◽  
Tomáš Malý ◽  
Lucia Malá ◽  
Miloslav Ejem ◽  
Marek Zawartka

Abstract The aim of the study was to describe and compare kinematics in two types of execution of attack hit, the goofy approach and regular approach. The research group consisted of players from the Czech Republic’s top league (n = 12, age 28.0 ± 4.3 years, body height 196.6 ± 5.6 cm, body mass 89.7 ± 6.7 kg) divided into two groups according to the individual type of approach in the attack. Analysis of movement was performed by 3D kinematics video analysis, space coordinates were calculated by the DLT (Direct Linear Transformation) method together with interpretation software TEMA Bio 2.3 (Image Systems AB, Sweden). The players started their run-up from a distance of about 4 – 4.5 m from the net with similar maximal vertical velocity (2.91 – 2.96 m⋅s-1). The trajectory of players with goofy approach seemed to be convenient for the rotation of shoulders and hips in the moment of ball contact. Differences between both groups were observed. Players with a goofy approach had a longer flight phase compared to regularly approaching players.

2009 ◽  
Vol 2009 (1) ◽  
pp. 61-78
Author(s):  
Petr Kouba

This article examines the limits of Heidegger’s ontological description of emotionality from the period of Sein und Zeit and Die Grundbegriffe der Metaphysik along the lines outlined by Lévinas in his early work De l’existence à l’existant. On the basis of the Lévinassian concept of “il y a”, we attempt to map the sphere of the impersonal existence situated out of the structured context of the world. However the worldless facticity without individuality marks the limits of the phenomenological approach to human existence and its emotionality, it also opens a new view on the beginning and ending of the individual existence. The whole structure of the individual existence in its contingency and finitude appears here in a new light, which applies also to the temporal conditions of existence. Yet, this is not to say that Heidegger should be simply replaced by Lévinas. As shows an examination of the work of art, to which brings us our reading of Moravia’s literary exposition of boredom (the phenomenon closely examined in Die Grundbegriffe der Metaphysik), the view on the work of art that is entirely based on the anonymous and worldless facticity of il y a must be extended and complemented by the moment in which a new world and a new individual structure of experience are being born. To comprehend the dynamism of the work of art in its fullness, it is necessary to see it not only as an ending of the world and the correlative intentional structure of the individual existence, but also as their new beginning.


2020 ◽  
Author(s):  
Adam Wiesner

With a conscious attempt to contribute to contemporary discussions in mad/trans/queer/monster studies, the monograph approaches complex postmodern theories and contextualizes them from an autoethnographic methodological perspective. As the self-explanatory subtitle reads, the book introduces several topics as revelatory fields for the author’s self-exploration at the moment of an intense epistemological and ontological crisis. Reflexively written, it does not solely focus on a personal experience, as it also aims at bridging the gap between the individual and the collective in times of global uncertainty. There are no solid outcomes defined; nevertheless, the narrative points to a certain—more fluid—way out. Through introducing alternative ways of hermeneutics and meaning-making, the book offers a synthesis of postmodern philosophy and therapy, evolutionary astrology as a symbolic language, embodied inquiry, and Buddhist thought that together represent a critical attempt to challenge the pathologizing discursive practices of modern disciplines during the neoliberal capitalist era.


2016 ◽  
Vol 53 (1) ◽  
pp. 179-187 ◽  
Author(s):  
José Vilaça-Alves ◽  
Nuno Miguel Freitas ◽  
Francisco José Saavedra ◽  
Christopher B. Scott ◽  
Victor Machado dos Reis ◽  
...  

AbstractThe aim of this study was to compare the values of oxygen uptake (VO2) during and after strength training exercises (STe) and ergometer exercises (Ee), matched for intensity and exercise time. Eight men (24 ± 2.33 years) performed upper and lower body cycling Ee at the individual’s ventilatory threshold (VE/VCO2). The STe session included half squats and the bench press which were performed with a load at the individual blood lactate concentration of 4 mmol/l. Both sessions lasted 30 minutes, alternating 50 seconds of effort with a 10 second transition time between upper and lower body work. The averaged overall VO2 between sessions was significantly higher for Ee (24.96 ± 3.6 ml·kg·min-1) compared to STe (21.66 ± 1.77 ml·kg·min-1) (p = 0.035), but this difference was only seen for the first 20 minutes of exercise. Absolute VO2 values between sessions did not reveal differences. There were more statistically greater values in Ee compared to STe, regarding VO2 of lower limbs (25.44 ± 3.84 ml·kg·min-1 versus 21.83 ± 2·24 ml·kg·min-1; p = 0.038) and upper limbs (24.49 ± 3.84 ml·kg·min-1 versus 21.54 ± 1.77 ml·kg·min-1; p = 0.047). There were further significant differences regarding the moment effect (p<0.0001) of both STe and Ee sessions. With respect to the moment × session effect, only VO2 5 minutes into recovery showed significant differences (p = 0.017). In conclusion, although significant increases in VO2 were seen following Ee compared to STe, it appears that the load/intensity, and not the material/equipment used for the execution of an exercise, are variables that best influence oxygen uptake.


1982 ◽  
Vol 35 (2) ◽  
pp. 155 ◽  
Author(s):  
PL Dyson ◽  
JA Bennett

A general expression, applicable at VHF and above, is derived for the Doppler shift of radio signals transmitted between two satellites embedded in the ionosphere. The Doppler shift is made up of several contributions which depend on (a) the rate of change of the free space path between the satellites, (b) the components, perpendicular to the line of sight between the satellites, of both the mean velocity of the satellites and the electron concentration gradients, (c) the moment of the perpendicular electron concentration gradients and the deviations from the mean of the individual satellite perpendicular velocities, (d) the velocity components along the line of sight between the satellites, and the electron concentration values at each satellite, and (e) changes occurring in the ionosphere with time.


Author(s):  
Irina Stanislavovna Morozova ◽  
Evgeniia Aleksandrovna Medovikova ◽  
Daria Nikolaevna Grinenko ◽  
Anastasiia Evgenevna Kargina

The actual problem of our time at the enterprises of the Kuzbass coal industry is the moment of ensuring the psychological security of the employee's personality. Psychological security is a fairly broad concept that includes many components and is exposed to various factors [2]. The aim of the study is to consider the importance of self-regulation of the individual as a condition for ensuring the safety of the subject of professional activity. The following methods and techniques were used in the study: The method "Style of self-regulation of behavior" by V. I. Morosanova; Test "Meaning-life orientations" by D. A. Leontiev; Questionnaire by H. Zachera and M. Freze "Professional time perspective of the future". The research is based on the development and testing of the technology of psychological and pedagogical influence in the form of reflexive seminars, which allows to increase the level of awareness of self-regulation of subjects of professional activity.


2020 ◽  
Vol 13 (3) ◽  
pp. 279
Author(s):  
Laura Elizabeth Cervantes Benavides

Facing the problems for understanding student learning and the way that makes the relationship and integration of learned knowledge easier, this work is presented, which objective is to identify in the teaching-learning process, at the moment in which the individual relates and integrates the knowledge it acquires. In this document, the assumption was made is, In greater depth of reflection, the student strengthens his cognitive and metacognitive abilities.


2020 ◽  
Vol 5 ◽  
Author(s):  
Martin Szénay ◽  
Martin Lopušniak

In 2010 it was defined five challenges for the solution of evacuation of persons in buildings to 2020. One of the challenges is to implement helpfull technologies during evacuations from buildings – lifts. Needed steps for fulfilling this challenge are also quantification of missing data which are dealing with evacuation of persons with disabilities. From 2002 all public buildings in Slovak Republic have to be also accessible to persons with disabilities, but it is also a global problem. In present exists just small number of informations of movement parameters of persons with disabilities during evacuation by lift. There for, this work was focused on collecting these informations. The data collection was realized by using an in-situ experiment. The aim of the work was to quantify the phase stages of evacuation by elevators for persons with disabilities (speed, time, movement and capacity parameters). Person's movements were monitored during the measurements, arrival to lift, cabin entry and exit from the cabin, including leaving the bounded area. Arrival to lift included movement in the bounded area in front of the lift, until the moment of pushing the button was pressed to call the lift. The time of cabin entering includes the time from the beginning of opening the lift doors to the beginning of closing of the lift doors. The exit from the cabin includes the time from opening the lift doors, passing through the lift doors to leaving the bounded area. In total, ten participating persons in the experiments imitated wheelchair movement and movement with leg fracture. Measurements were made on two lifts, where person evacuating himself or with the help of another person. Everyone performed each measurement three times. A total of 720 measurements were performed in the work. According to the results of the experiment it can be stated that cabin entry is longer for a person on the wheelchair than for a person with a leg fracture, but the difference is even bigger during exit from the cabin, including leaving the bounded area. During the experiment, various movement techniques have been observed that may affect their overall the time of cabin entry and exit from the cabin. Obtained results can extend existing evacuation model to the possibility of using the lift. The obtained results quantify the individual phase stages of entering to the lift and exiting of the lift for persons with limited movement.


1978 ◽  
Vol 19 (1) ◽  
pp. 25-38 ◽  
Author(s):  
Anne Summers ◽  
R. W. Johnson

When the French government introduced military conscription into the A.O.F. in 1912, the Guinean colonial authorities saw the measure as a means of training a local administrative corps to replace the traditional chieftaincy, through whose military defeat the conquest of Guinea had very largely been effected. However, the chiefs had by no means disappeared by 1914, and wartime demands for recruits were too massive to be supplied without their assistance. Their help was bought with promises to consolidate their authority in peacetime. Although able to marshal recruits, the chiefs seem to have been unable to prevent large-scale desertions before the moment of embarkation for France; village populations could also avoid conscription by overland migration out of the A.O.F. The colonial authorities therefore felt constrained to offer substantial inducements, mainly concerning improved social status vis-à-vis the chiefs, to the individual recruits. These contradictory policies were compounded by the recruitment drive of Blaise Diagne in 1918, which involved a further promise to recruits of improved status vis-à-vis the French authorities. The return of ancien combattants to Guinea was marked by outbreaks of strike action among workers in Conakry and along the railway line; by riots in demobilization camps; and by rejection of or agitation against chiefly power in the home cantons to which they dispersed. The anciens combattants did not form a coherent or organized political movement, but remained a conspicuous social grouping between the wars. Although they appear to have been strongly influenced by their experience of war and by contact with French socialists, their conflict with the chiefs seems to have counted for more with them than any confrontation with the French.


2021 ◽  
Vol 1 (1) ◽  
pp. 25-40
Author(s):  
Neriman Aral

From the moment the child is born, learning becomes meaningful and it is interpreted as a result of the experiences first in the family and then in school. However, it is sometimes not possible to talk about the fact that learning takes place in all children although the process has taken place in this direction. Sometimes the individual differences that exist in children and the inability to get the necessary support in structuring their learning experiences can be effective in the failure of learning, while sometimes the type of congenital difficulty can be effective. One of these types of difficulty is a specific learning difficulty. It is not always possible for children with specific learning difficulties to learn, even if they do not have any mental problems. In this case, many factors can be effective, especially the problems that children experience in their visual perception can become effective. Since visual perception is the processing of symbols received from the environment in the brain, the problem that may be experienced in this process can also make it difficult to learn this situation. In line with these considerations, it is aimed to focus on the importance of visual perception in specific learning difficulties.


Author(s):  
José Luis Bermúdez

My principal reason for revisiting and combining the essays in this volume was that they all converge on and develop a small number of basic themes. In the introduction, I try to bring those themes out and explain how the individual essays contribute to developing them. However, the process of editing the essays and thinking about how they connect together had a consequence that I probably should have foreseen. It made very clear where more work needs to be done. For that reason, I was very pleased when the referees for this volume suggested that I write an afterword identifying some of the challenges (and, hopefully, opportunities) that lie ahead in this area. I welcome being able at least to identify some of the gaps and problems that remain, even if I am not in a position at the moment to fill and solve them. But since this enterprise may seem a little self-indulgent, I will strive for brevity....


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