E. Segovia

Acceleration and Deflection Analysis for Class C Edge Protection Systems in Construction Work

B. Ferrer acknowledges the support of the Generalitat Valenciana through the project GV/2013/009 and the Spanish Ministerio de Economia y Competitividad through the project BIA2011-22704.

Sistemas de protección individual anticaídas sometidos a impacto. Simulaciones numéricas

Personal fall protection systems are set up by EN-363 to avoid or retain people falls safely (without relevant damages). They are the ultimate resource to prevent a fall after other measures being considered. This paper analyses the variables affecting the system behaviour: free fall height, length of retaining rope, stiffness and damping of retaining material, and worker weight. To this end, fall phenomenon has been simulated with finite elements dynamic models with an elas- tic rope and a rigid ballast. It allows obtain likely values of maximum forces on the injured and over the system during the impact. Results demonstrate the fundamental role of height fall vs. rope length rate (fall factor), which results more important than the fall height itself. The severe values obtained for maximum forces show that future research would include elastoplastic energy absorbers to decrease impact until reasonable values.

Numerical analysis of the vibrational behavior of the moving assembly of a dynamic loudspeaker

This paper describes the process undertaken to analyze numerically the vibrational behavior of the moving assembly of a dynamic loudspeaker with double bottom suspension and in the absence of the above one using the finite element method (FEM). The study focuses on the low frequency range. Model calibration was performed based on experimental measurements of the resonance frequency and diaphragm displacement. The importance of the participation factors associated to the excitation force and the changes produced in these when unbalanced forces are introduced are emphasized. The analysis also provides data to decide on the distance between suspensions, their optimal number of folds and the placement of the lead wires, parameters of great interest on the design of this type of loudspeakers.

Análisis numérico del comportamiento vibratorio del conjunto móvil de un altavoz dinámicoNumerical analysis of the vibrational behavior of the moving assembly of a dynamic loudspeaker

This paper describes the process undertaken to analyze numerically the vibrational behavior of the moving assembly of a dynamic loudspeaker with double bottom suspension and in the absence of the above one using the finite element method (FEM). The study focuses on the low frequency range. Model calibration was performed based on experimental measurements of the resonance frequency and diaphragm displacement. The importance of the participation factors associated to the excitation force and the changes produced in these when unbalanced forces are introduced are emphasized. The analysis also provides data to decide on the distance between suspensions, their optimal number of folds and the placement of the lead wires, parameters of great interest on the design of this type of loudspeakers.

Análisis numérico del comportamiento vibratorio del conjunto móvil de un altavoz dinámico

This paper describes the process undertaken to analyze numerically the vibrational behavior of the moving assembly of a dynamic loudspeaker with double bottom suspension and in the absence of the above one using the finite element method (FEM). The study focuses on the low frequency range. Model calibration was performed based on experimental measurements of the resonance frequency and diaphragm displacement. The importance of the participation factors associated to the excitation force and the changes produced in these when unbalanced forces are introduced are emphasized. The analysis also provides data to decide on the distance between suspensions, their optimal number of folds and the placement of the lead wires, parameters of great interest on the design of this type of loudspeakers.