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This article introduces a new kinematic modeling method used to analyze coupled rigid multibody movements. The method was applied to the study of a 5R planar parallel mechanism's kinematics and consists of analyzing two fixed configurations of the mechanism to systematize the rotational relationships between the two structures. Mathematical models were developed using complex numbers. The inverse kinematic problem was modeled as a system of eight nonlinear equations and eight unknowns, which was solved with Newton-Raphson's method. Subsequently, with the inverse problem model, a numerical database related to the mechanism configurations, including singular positions, was generated to train a multilayer neural network. The Levenberg-Marquardt algorithm was used for network training. Finally, an interpolated linear path was used to understand the efficiency of the trained network.

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La utilidad de las predicciones económicas es un hecho constatado en los países desarrollados para anticiparse a la toma de decisiones o a la aplicación concreta de políticas económicas. El tráfico aéreo de pasajeros es una de las principales magnitudes de actividad económica de un país, especialmente relevante en España, destino turístico internacional de primera magnitud. En este trabajo abordamos la realización de predicciones del tráfico total de pasajeros aéreos a nivel nacional a partir de la evolución mensual disponible en AENA, con modelos SARIMAX. Examinamos si, y en qué medida, el poder predictivo del tráfico aeroportuario de pasajeros en España, en términos agregados, puede ser mejorado mediante el uso de información más detallada e individualizada, a través de un enfoque desagregado (procedente de la suma de las predicciones realizadas para los diferentes aeropuertos regionales), en términos de la fiabilidad y precisión de los resultados.

The failures, unexpected and catastrophic, are presented in large mechanical systems, specifically, in the electric power generation. The development of new methodologies of analysis and research to evaluate and calculate useful life must be proposed. In this work, an analytical-experimental novel methodology was developed using laws of similarity and models at the scale of prototypes, parts or mechanical components of any system. The methodology developed in the dynamic study of steam turbine blades was applied to calculate their stresses, deformations and the prediction of their useful life in mechanical fatigue conditions. The analytic-experimental and numerical results showed a relative error of less than 3,16% for both models. The new methodology was validated with these results. The use of scale models with the application of similarity laws will be of help in the analysis of failures where due to the size or high costs, real systems cannot be analyzed. Keywords: scale models, experimental analysis, deformations, similarity laws, useful life, mechanical fatigue