Ajuste fino de un modelo de producción vocal para estimar el estrés de impacto utilizando un método metaheurístico

Introducción: En modelos de producción vocal que emplean estructuras de resorte-masa-amortiguador, la precisión en la determinación de coeficientes de amortiguamiento que se asemejen a las características fisiológicas de las cuerdas vocales es crucial, teniendo en cuenta posibles variaciones en la representación de la viscoelasticidad. Objetivo: Este estudio tiene como objetivo realizar un ajuste paramétrico de un modelo de producción vocal basado en un sistema de resorte-masa-amortiguador que incorpora interacción con la presión subglótica, con el fin de modelar de manera precisa las fuerzas de colisión ejercidas por las cuerdas vocales durante la fonación. Método: Se utilizó un algoritmo de búsqueda metaheurística para la síntesis paramétrica. El algoritmo se aplicó a los coeficientes de elasticidad c1 y c2, así como a los coeficientes de amortiguamiento ε1 y ε2, que se correlacionan directamente con las matrices de masa del modelo. Esto facilita el ajuste de la composición de las cuerdas para lograr un comportamiento fisiológico deseado. Resultados: El comportamiento del sistema vocal para cada ciclo de simulación se comparó con un estándar predefinido en condiciones normales. El algoritmo determinó el punto final de la simulación evaluando las discrepancias entre características clave de las señales obtenidas y las deseadas. Conclusión: El ajuste paramétrico permitió la aproximación del comportamiento fisiológico de la producción vocal, proporcionando estimaciones de las fuerzas de impacto experimentadas por las cuerdas vocales durante la fonación.

Introduction: In vocal production models employing spring-mass-damper frameworks, precision in determining damping coefficients that align with physiological vocal fold characteristics is crucial, accounting for potential variations in the representation of viscosity-elasticity properties. Objective: This study aims to conduct a parametric fitting of a vocal production model based on a mass-spring-damper system incorporating subglottic pressure interaction, with the purpose of accurately modeling the collision forces exerted by vocal folds during phonation. Method: A metaheuristic search algorithm was employed for parametric synthesis. The algorithm was applied to elasticity coefficients c1 and c2, as well as damping coefficients ε1 and ε2, which directly correlate with the mass matrices of the model. This facilitates the adjustment of fold composition to achieve desired physiological behavior. Results: The vocal system's behavior for each simulation cycle was compared to a predefined standard under normal conditions. The algorithm determined the simulation endpoint by evaluating discrepancies between key features of the obtained signals and the desired ones. Conclusion: Parametric fitting enabled the approximation of physiological vocal production behavior, providing estimates of the impact forces experienced by vocal folds during phonation.

Biomechanical Models to Represent Vocal Physiology: A Systematic Review.

Biomechanical modeling allows obtaining information on physical phenomena that cannot be directly observed. This study aims to review models that represent voice production. A systematic review of the literature was conducted using PubMed/Medline, SCOPUS, and IEEE Xplore databases. To select the papers, we used the protocol PRISMA Statement. A total of 53 publications were included in this review. This article considers a taxonomic classification of models found in the literature. We propose four categories in the taxonomy: (1) Models representing the Source (Vocal folds); (2) Models representing the Filter (Vocal Tract); (3) Models representing the Source - Filter Interaction; and (4) Models representing the Airflow - Source Interaction. We include a bibliographic analysis with the evolution of the publications per category. We provide an analysis of the number as well of publications in journals per year. Moreover, we present an analysis of the term occurrence and its frequency of usage, as found in the literature. In each category, different types of vocal production models are mentioned and analyzed. The models account for the analysis of evidence about aerodynamic, biomechanical, and acoustic phenomena and their correlation with the physiological processes involved in the production of the human voice. This review gives an insight into the state of the art related to the mathematical modeling of voice production, analyzed from the viewpoint of vocal physiology.

Parallel assistive robotic system for knee rehabilitation: kinematic and dynamic modeling validation.

The knee joint is frequently exposed to injuries in people of all ages. In some cases, physical therapy is prescribed to recover the strength and mobility of a patient. The robotic assistance devices are gaining community attention and aim to improve the quality of life of people. In this work, we present the kinematic and dynamic modelling of a five-bar-linkage assistive device for knee rehabilitation according to anthropometric data from Latin-American population. We obtain a dynamic model of the proposed rehabilitation system and compare the knee trajectories with obtained using the assistive system to evaluate appropriate control strategies in the future. For this purpose, we present the kinematic formulation of the device, and then we derive the dynamics using two approaches to validate the model; we obtain the motion equation using the Lagrange approach and an algebraic method that simplifies modelling. Both approaches yield a unique model, which is validated either in simulation and by experimental trials, showing the functionality of the system and the validity of the models when performing rehabilitation routines.

Investigaciones y comprensiones del conflicto armado en Colombia. Salud mental y familia / Investigations and Understandings of the Armed Conflict in Colombia. Mental Health and Family

Resumen Este artículo presenta el resultado de un proceso de indagación documental en el campo de la salud mental, con énfasis en la psicología clínica y la familia en el contexto del conflicto armado colombiano. Su propósito es intentar comprender los órdenes de la producción de explicaciones sobre los fenómenos psicopatológicos en contexto de la confrontación armada y los desarrollos metodológicos, las técnicas de intervención, considerando los impactos científicos y sociales del conflicto. Se analizaron 62 documentos entre fuentes primarias y secundarias, correspondientes a un periodo de los últimos 15 años, evidenciando el desarrollo de las tendencias con la contextualización histórica y el desarrollo de la política pública de atención a la salud mental de las víctimas. Se configuraron ejes de búsqueda como medios de conexión y articulación del problema social: los mecanismos argumentativos de las diferentes disciplinas (conflicto armado y contexto social), la intensión de las investigadoras (salud mental y trastornos psicopatológicos) y el problema de investigación (familias y conflicto armado).

Abstract This article presents the result of a process of documentary inquiry in the field of mental health, with emphasis on clinical psychology and the family in the context of the Colombian armed conflict. Its purpose is to approach an attempt to understand the orders of the production of explanations on psychopathological phenomena in a context of war and methodological developments, intervention techniques, considering the scientific and social impacts of conflict. We analyzed 62 documents between primary and secondary sources, corresponding to a period of the last 15 years, taking in to consideration the development of trends with historical contextualization, and the development of the public policy of attention to the mental health of the victims. Research axes were configured as means of connection and articulation between the social problem from the argumentative mechanisms of the different disciplines (armed conflict and social context), the researcher´s intentions (mental health and psychopathological disorders) and the research problem and armed conflict).