This investigation carries out the biomechanical modeling of the knee with the purpose of contributing to rehabilitation therapies for patients who come to the Patronato of Latacunga, through a mathematical model that serves as initial support for the design and the construction of physiotherapy equipment, guaranteeing functionality, safety, and ergonomics to the patients. With the data from the anthropometric study of the population under study, the mathematical variables have been introduced to create a mathematical model with the help of MATLAB/Simulink tool with a focus on the modeling of physical systems, by taking the mechanical system as a biomechanical research because it acts on the bodies in a way that gives them movement, analyzing their laws, variables and elements. A bibliographic method has been used to collect the data, the analytical method to analyze data and variables and the experimental method through the simulation of the model, the developed model is perfectly adaptable to any person, by only changing the variables of the matrix. Copyright © 2022 Praise Worthy Prize - All rights reserved.

En un mundo globalizado las empresas necesitan decisiones acertadas que les permita reducir el estrés financiero al pertenecer a una economía volátil. El presente artículo tiene como objetivo medir el nivel y conocer las causas del estrés financiero de quienes son dueños o administradores de las pequeñas y medianas empresas en Quito, Ecuador. La investigación es de tipo descriptiva, bibliográfica-documental. Se aplicaron encuestas con escala Likert a personeros de las 379 empresas determinadas en la muestra y los datos fueron procesados en el programa IBM SPSS 24. Los resultados indican que el 82,32% de esta clase de empresas tiene un nivel de estrés financiero alto y esto obedece al temor de pérdidas financieras y el endeudamiento que mantienen. El estrés financiero se genera en mayor nivel en la población con rango de edad 20 a 41 años, en tanto que quienes tienen más de 41 años es medio y bajo. Las pequeñas empresas y el sector comercial son quienes se ven más afectados por el estrés financiero, lo que denota la fragilidad de este sector. Los indicadores financieros son una alternativa para tener una visión sobre las empresas y tomar decisiones oportunas para evitar el estrés financiero.

Power outages pose a significant challenge to the operational continuity of businesses and infrastructure that rely on critical loads. In this context, hybrid photovoltaic systems with energy storage represent a sustainable alternative for improving energy resilience and reducing dependence on conventional backup sources. The objective of this research was to design, implement, and experimentally validate a hybrid photovoltaic system with battery storage for critical-load backup in a commercial facility located in Quito, Ecuador. The methodology included energy-demand assessment, photovoltaic and battery storage sizing, integration of an automatic transfer system, and experimental evaluation under real operating conditions. In addition, a mathematical model was developed to describe the system’s energy behavior, including a backup-autonomy model validated against experimental data. The results showed that the system maintained the power supply to critical loads during controlled grid-interruption events, achieving an average backup autonomy of 3.2 h under an approximate demand of 2.2 kW. The hybrid backup system delivered approximately 7.04 kWh during representative backup events through the combined contribution of photovoltaic generation and battery storage. Furthermore, the backup-autonomy model showed a relative error of 1.9% with respect to the experimental measurements, demonstrating good agreement between the theoretical model and the observed performance. The findings confirm the technical feasibility of hybrid photovoltaic systems for improving energy resilience in critical-load applications. The main contribution of this study is the experimental validation of a commercially implemented hybrid photovoltaic backup system under real operating conditions, providing empirical evidence and a replicable methodology for future implementations in similar commercial and industrial facilities.