Centre for Mechanical Enginnering, Materials and Processes

Publicações

Visual Fixations in Basketball Shooting: Differences between Shooting Conditions

Publication . Amaro, Catarina M.; Castro, Maria António; Mendes, Rui; Gomes, Beatriz B.

Basketball is a sport where shooting is one of the most important factors that determines the success or failure of the teams. Therefore, basketball players need to shoot the ball accurately. The present study aimed to evaluate whether different shooting conditions influence the visual behavior of athletes. For this, the Tobbi Pro Glasses 3 equipment was used to evaluate the time of the first fixation, the number of fixations, and the total time of fixations in the basket, during the shooting movement. Different distances to the basket, simulated gym audience noise, and shooting with opposition were considered. A group of 18 athletes with an average age of 22 ± 3.72 years and an average basketball practice experience of 12.5 ± 4.52 years performed 10 valid shots from different distances and different shooting angles, with different restrictions, namely, shooting with simulated opposition and gym audience noise. Statistically significant differences between shooting with opposition and baseline, in terms of the number of fixations and the total time of fixation, were found. Regarding shooting with gym audience noise, differences only occur for the total time of fixations in one position. Despite this, in all variables and positions, the values were lower in shooting with constraints compared to the baseline.

2024-04-09Artigo científico

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Strain sequence effect on fatigue life and fracture surface topography of 7075-T651 aluminium alloy

Publication . Macek, Wojciech; Branco, Ricardo; Costa, José Domingos; Pereira, Cândida

The paper studies the effect of strain-loading sequence on fatigue lifetime and fracture surface topographies in 7075-T651 aluminum alloy specimens. Fatigue tests were performed in two ways: (i) constant-amplitude loading and (ii) two series of variable amplitude loading with non-zero mean strain values. The topography of the fatigue fractures was measured over their entire surfaces with the help of an optical confocal measurement system. The results of fatigue tests in the form of equivalent strains, εaeq, such as the weighted mean of strain components, εa1, εa2, and fatigue life, Nf, were used as the sum of the partial number of cycles N1, and N2. This study indicates, inter alia, that the values of the fracture surface parameter core height Sk, found in the two-step loading program, are linearly dependent on the equivalent strain, and logarithmically dependent on the fatigue life.

2021-09Artigo científico

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Palavras-chave

Intelligent manufacturing,Desenvolvimento & Teste,Surface and Interface Engineering,Nanomaterials and Nanotechnology,

Entidade financiadora

Fundação para a Ciência e a Tecnologia, I.P.
Fundação para a Ciência e a Tecnologia, I.P.

Programa de financiamento

6817 - DCRRNI ID
Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017/2018) - Financiamento Base

Número da atribuição

UIDB/00285/2020