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This article states that research in skill acquisition and execution has underestimated the relevance of some features of attention. We present and theoretically discuss two essential features of attention that have been systematically overlooked in the research of skill acquisition and execution. First, attention alters the appearance of the perceived stimuli in an essential way; and second, attention plays a fundamental role in action, being crucial for solving the so called ’many-many problem’, that is to say, the problem of generating a coherent behavior by selecting between many inputs and many potential outputs. We discuss the importance of these features for skill acquisition in sport. We also suggest empirical ways to assess the precise impact of taking them into consideration and at the same time we propose important implications for training derived from the ideas discussed in the paper.

El diseño de piezas industriales supone un claro ejemplo de esfuerzo integrador que, con un enfoque interdisciplinar, requiere un análisis detallado de los diferentes conocimientos científicos y tecnológicos implicados en su concepción y desarrollo. Dentro de este marco de actuación, el presente trabajo aborda la problemática del proyecto de piezas estampadas en caliente, proponiendo la utilización de criterios de viabilidad y optimización que, fundamentados en consideraciones técnico-económicas, permiten valorar el grado de adecuación de las diferentes alternativas al proceso de forja, facilitando con ello la selección de la más adecuada. Fijadas estas bases y con objeto de acortar tiempos de respuesta y análisis en una aplicación correspondiente a piezas axisimétricas, se ha introducido un sistema informatizado que, tomando como dato de partida el plano de mecanizado de la pieza, simula geométricamente el proceso de estampación, permitiendo calcular los coeficientes de adecuación en aquellas tipologías que son posibles según los criterios de viabilidad. Este sistema también proporciona una representación gráfica de pieza mecanizada, pieza estampada y matriz de acabado.

This work presents a hybrid (experimental-computational) application for improving the vibration behavior of structural components using a lightweight multilayer composite. The vibration behavior of a flat steel plate has been improved by the gluing of a lightweight composite formed by a core of polyurethane foam and two paper mats placed on its faces. This composite enables the natural frequencies to be increased and the modal density of the plate to be reduced, moving about the natural frequencies of the plate out of excitation range, thereby improving the vibration behavior of the plate. A specific experimental model for measuring the Operating Deflection Shape (ODS) has been developed, which enables an evaluation of the goodness of the natural frequencies obtained with the computational model simulated by the finite element method (FEM). The model of composite + flat steel plate determined by FEM was used to conduct parametric study, and the most influential factors for 1st, 2nd and 3rd mode were identified using a multifactor analysis of variance (Multifactor-ANOVA). The presented results can be easily particularized for other cases, as it may be used in cycles of continuous improvement as well as in the product development at the material, piece, and complete-system levels.

BACKGROUND: Musculoskeletal disorders (MSDs) that result from poor ergonomic design are one of the occupational disorders of greatest concern in the industrial sector. A key advantage in the primary design phase is to focus on a method of assessment that detects and evaluates the potential risks experienced by the operative when faced with these types of physical injuries. The method of assessment will improve the process design identifying potential ergonomic improvements from various design alternatives or activities undertaken as part of the cycle of continuous improvement throughout the differing phases of the product life cycle. METHODOLOGY/PRINCIPAL FINDINGS: This paper presents a novel postural assessment method (NERPA) fit for product-process design, which was developed with the help of a digital human model together with a 3D CAD tool, which is widely used in the aeronautic and automotive industries. The power of 3D visualization and the possibility of studying the actual assembly sequence in a virtual environment can allow the functional performance of the parts to be addressed. Such tools can also provide us with an ergonomic workstation design, together with a competitive advantage in the assembly process. CONCLUSIONS: The method developed was used in the design of six production lines, studying 240 manual assembly operations and improving 21 of them. This study demonstrated the proposed method's usefulness and found statistically significant differences in the evaluations of the proposed method and the widely used Rapid Upper Limb Assessment (RULA) method.