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Spatial and spatiotemporal interpersonal coordinations in jiyu waza
No full textAo longo dos últimos anos a coordenação interpessoal tem sido cada vez mais reconhecida como um importante conceito na compreensão de desempenhos esportivos. Ela se refere às interações de cooperação e oposição entre indivíduos. O presente estudo teve como objetivo investigar a coordenação interpessoal no jiyu waza. Especificamente, buscou-se identificar as medidas es paciais e espaciotemporais que caracterizaram a coordenação interpessoal no jiyu waza. Partici param do estudo vinte aikidoístas, com média de idade de 30 anos (± 5 anos), com o grau mínimo de shodan (1º grau da faixa preta) e mínimo de 8 anos de prática no aikidô. A tarefa foi o jiyu waza, que consistiu em um aikidoísta defensor não se deixar cercar e/ou ser atingido por três oponentes. Área triangular, forma/tipo triangular e distância interpessoal, em conjunto com suas respectivas medidas de taxas de mudança (variabilidade e velocidade) foram utilizadas como medidas de coordenação interpessoal. As coordenadas x e y de deslocamento dos participantes foram obtidas em filmagens de 30 segundos (1800 quadros a 60 fps) usando o software de ras treamento semiautomático Kinovea 0.9.5. A filmagem foi realizada de cima considerando o topo da cabeça de cada participante como ponto de rastreamento. Os resultados revelaram que: (1) as coordenações interpessoais dos atacantes, em forma de triângulos escaleno e obtusângulo, com áreas mais variáveis e as maiores distâncias interpessoais entre o defensor e o triângulo caracte rizaram as defesas; (2) os ataques em que o defensor é atacado pela frente, mas não consegue neutralizar o ataque, foram caracterizados por distâncias interpessoais superiores que emergiram com superiores velocidades positivas; (3) as situações em que o defensor é atacado pelas costas, mas não consegue neutralizar o ataque, foi caracterizada pelas coordenações interpessoais re presentadas pelos triângulos escaleno e obtusângulo. Portanto, as medidas triangulares (área e forma/tipo) foram capazes de capturar a coordenação interpessoal de cooperação entre os ata cantes e, a distância interpessoal possibilitou o acesso a coordenação interpessoal relativa à opo sição no jiyu wazaOver the past few years, interpersonal coordination has been increasingly recognized as an im portant concept in understanding sports performance. It refers to the interactions between indi viduals. The present study aimed to investigate the interpersonal coordination in jiyu waza. Spe cifically, it sought to identify the spatial and spatiotemporal measures that characterized inter personal coordination in jiyu waza. Twenty aikido practitioners participated in the study, with a mean age of 30 years (± 5 years), with a minimum rank of shodan (1st degree black belt) and a minimum of 8 years of aikido practice. The task was jiyu waza, which consisted of a defending aikido practitioner avoiding being surrounded and/or hit by three opponents. Triangular area, triangular shape/type, and interpersonal distance, together with their respective measures of change rates (variability and velocity) were used as measures of interpersonal coordination. The x and y coordinates of the participants\' displacement were obtained from 30-second filming (1800 frames at 60 fps) using the semi-automatic tracking software Kinovea 0.9.5. The filming was performed from above, considering the top of each participant\'s head as the tracking point. The results revealed that: (1) the attackers\' interpersonal coordinations in the form of scalene and obtuse triangles, with more variable areas, as well as the greater interpersonal distances between the defender and the triangles characterized the defenses; (2) the attacks in which the defender is attacked from the front, but is unable to neutralize it, were characterized by greater interpersonal distances that emerged with greater positive velocities; (3) the situations in which the defender is attacked from behind, but is unable to neutralize the attack, were characterized by the interpersonal coordinations represented by the scalene and obtuse triangles. Therefore, the triangular measures (area and shape/type) were able to capture the interpersonal coordination of cooperation between the attackers, and the interpersonal distance enabled access to the inter personal coordination relative to the opposition in jiyu waz
Effects of specific cues on learning an aikido motor skill.
No full textInvestigou-se os efeitos das dicas instrucionais na aprendizagem da habilidade motora choku tsuki do aikido. Sessenta participantes dos sexos masculino e feminino, com idade média de 14,1 anos (± 0,4) foram recrutados para o estudo. Os mesmos foram divididos em quatro grupos: relaxamento (dica que direcionava a atenção para a maneira relaxada como a tarefa deveria ser executada); quadril baixo (dica que direcionava a atenção para manter o deslocamento do quadril o mais baixo possível); perceptiva (dica que direcionava a atenção para um alvo circular localizado no peito do oponente enquanto ele levantava a espada para atacar); e controle (sem dica). As variáveis dependentes incluíram medidas relacionadas aos objetivos da tarefa (erro relativo ao alvo, erro relativo à empunhadura do oponente e erro global), padrão de movimento relativo aos componentes da tarefa (posição inicial e movimentos dos membros superiores e inferiores) e características cinemáticas (distância entre quadril e chão, distância entre orelha e ombro, pico de velocidade de ataque, deslocamento do bastão e sincronização dos membros superiores e inferiores). Apenas os grupos perceptivo e quadril baixo aprenderam a habilidade motora. Além disso, o grupo perceptivo obteve melhor desempenho do que os outros grupos. Finalizando, os resultados do presente estudo permitem concluir que: (1) a dica estocar o alvo assim que levantar a espada foi aquela mais eficaz para a aprendizagem do choku tsuki por ter permitido ao aprendiz o acoplamento perceptivo com o oponente; (2) em um menor grau, a dica manter o quadril o mais baixo possível também mostrou-se eficaz para a promoção da aprendizagem do choku tsuki. Nesse caso, isso ocorreu porque a mesma possibilitou uma base adequada para a execução; (3) a dica orelhas afastadas dos ombros e articulações soltas não possibilitou a aprendizagemThe effect of different instructional cues on the learning of the choku tsuki motor skill in aikido was investigated. Sixty male and female participants with an average age of 14.1 years (± 0.4) were recruited to the study. They were divided into four groups: relaxation (cue that directed attention to the relaxed way in which the task should be performed); low hip (cue that directed attention to maintaining hip displacement as low as possible); perceptive (cue that directed attention to a circular target located on the chest of the opponent as they raised their sword to attack); and control (without cue). The dependent variables included measures related to the task goals (target error, sword hilt positioning error and global error), the movement pattern relative to the task components (starting position and upper and lower limb movements) and kinematic features (distance between hip and floor, distance between ears and shoulders, peak strike velocity, stick displacement and upper and lower limbs synchronisation). In conclusion: (1) \"stock target as soon as sword is raised\" cue was the most effective for learning choku tsuki for allowing the learner the perceptive coupling to the opponent; (2) to a lesser extent, \"keep your hip as low as possible\" cue has also been shown to be effective in promoting choku tsuki learning. In this case, this was because it allowed an adequate basis for performance; (3) ears apart from shoulders and loose joints cue did not allow learning
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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