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Objective: Due to the alarming rise in COVID-19 cases every day in India, numerous academics are already developing a variety of math-based estimation models to forecast the pandemic future course. This paper makes use of publicly available data to anticipate certain COVID-19 trajectories in India. Methods: We used the Auto-Regressive Integrated Moving Average Model, a time series model, to anticipate the number of COVID-19 infected cases every day soon. People need to consume nutritious food that is well-balanced and contains the right number of calories, nutrients, as well as vitamins for strong development, bearing in mind that sustaining and repairing bodily tissues is the goal while preventing unfavorable illnesses and disease. Results: Recent studies have shown that healthy eating can help lower the possibilities of developing cancer, cardiovascular disease and for COVID patients. Therefore, an optimization strategy and LINDO software was used to solve the model. This study offers an exhaustive daily meal plan created especially for hospital patients, acting as a helpful resource for school administrators. With six different food choices, the diet plan makes sure that you get all the nutrients you need each day at a reasonable price. Conclusions: The model is solved using LINDO software in the study, which shows how effective it is when compared to other heuristic techniques like biological algorithms. It is determined through thorough investigation that the chosen meals are both financially and nutritionally feasible to serve in ho spital settings. Hospital patients make up the study's participants, and each day's total cost comes to Rs109.34. This cost makes it possible to deliver meals that are minimally more costly but of higher quality, improving the patients' overall nutritional value. [ABSTRACT FROM AUTHOR]

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La ausencia de datos en series temporales de variables meteorológicas es un inconveniente en las ciencias ambientales, especialmente en lo que respecta a la precipitación, que es una variable clave en varios campos. El presente estudio se propuso comparar varios métodos estadísticos y matemáticos para generar datos pluviométricos faltantes en la microcuenca del río Pita, tales como el método de Paulhus y Kohler, la regresión lineal múltiple (RLM), la transformada de Wavelet y las redes neuronales artificiales; utilizando información de la red hidrometeorológica del Fondo para la Protección del Agua (FONAG) de Quito.

Este artículo tiene como objetivo comparar el rendimiento de dos controladores ampliamente utilizados en el control de sistemas dinámicos: el controlador PID (Proporcional-Integral-Derivativo) y el controlador LQR (Regulador Cuadrático Lineal). Se presenta una simulación detallada utilizando Simulink de MATLAB® para evaluar el comportamiento de un robot móvil autónomo auto equilibrado de dos ruedas. Se ha desarrollado un modelo matemático que describe con precisión el sistema del robot. Luego, se aplicaron técnicas de diseño específicas a cada controlador, y se observó el comportamiento resultante en términos de estabilidad y respuesta. Esta comparación tiene implicaciones importantes en el campo del control de sistemas autónomos y puede ayudar a determinar cuál de los dos controladores es más adecuado para aplicaciones particulares de robots móviles autónomos auto equilibrados.

La distribución de partículas es considerada una de las principales herramientas para el control en las distintas operaciones unitarias relacionadas al procesamiento de minerales. En las etapas de trituración y molienda esta técnica nos permite conocer el cómo ocurre la liberación del mineral valioso de la ganga, así como determinar los balances de materia. En el presente trabajo técnicas de análisis de imagen, el modelo de distribución de Weibull doble, así como propiedades físicas de un mineral de sílice, son empleadas para determinar una distribución granulométrica en estado estacionario. Para tal fin, la distribución de partículas determinada experimentalmente mediante el uso de mallas convencionales (Tipo Tyler) fue comparada con la obtenida mediante los fotogramas. El modelo de Weibull fue usado para ajustar matemáticamente la distribución obtenida mediante los fotogramas. El ajuste demostró ser una herramienta que permite determinar mediante el análisis de imagen una distribución granulométrica confiable, debido a que...

This work proposes a model for the dynamics of tuberculosis, which considers a latent low-risk population, with the aim of evaluating the importance of including it in the model and determining whether it is necessary to treat and/or control it. To this effect, a qualitative analysis of the model was carried out, determining which parameters are most relevant in the initial transmission of the disease and calculating the average number of new infections produced by an infectious individual. An optimal control problem was formulated and numerically solved, which seeks to minimize both the infected and the economic costs generated by the implementation of controls in the proposed dynamics of tuberculosis. Numerical simulations were used to analyze the effects of implementing the controls obtained. Finally, simulations are carried out for Cali (Colombia), establishing a methodology for the design of control strategies aimed at reducing the transmission of tuberculosis in the city. [ABSTRACT FROM AUTHOR]

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Contexto: El control y distribución de inventarios son procesos claves en la pérdida tanto de eficiencia como de eficacia en el campo de la logística, a nivel global. Según el Departamento Nacional de Planeación de Colombia, en el año 2020, los rubros de transporte, almacenamiento e inventarios correspondieron al 73,9 % del costo logístico total. La resolución del problema de enrutamiento inventario con múltiples vehículos (IRP) representa una alternativa para hacer que los tiempos de ciclo sean más cortos, más flexibles y menos costosos. Método: En este artículo se describen y comparan modelos matemáticos de la literatura para el problema base, adaptándolo a su variante con múltiples vehículos y resolviéndolo a través modelos de programación lineal entera mixta, mediante la solución de instancias de baja y media complejidad matemática, planteando dos maneras de gestionar el inventario y tres formas de eliminar la creación de sub-tours. Para obtener los resultados se utiliza el software AMPL en un computador con procesador Intel Core i5-5200U CPU @ 2.2 GHz y 4 GB de RAM, considerando un tiempo máximo de ejecución de una hora. Resultados: El modelo de flujos muestra el mejor desempeño en cuanto a tiempos computacionales y calidad de la respuesta con respecto a la política de máximo nivel (ML), y la variante MTZ es el segundo mejor modelo. Por último, la variación general reporta mayores tiempos de ejecución y valores GAP más altos. Los modelos presentan buen desempeño para instancias de pequeño y mediano tamaño. Conclusiones: En esta investigación se presenta una metodología general que puede ser adaptada a diferentes aplicaciones del problema integrado de inventarios y enrutamiento con múltiples vehículos. Se comprobó que las respuestas generadas son de buena calidad, destacando la eliminación de sub-tours por medio del modelo de flujos y la gestión de inventarios bajo la política ML. Los trabajos futuros deben encaminarse en busca de nuevas alternativas a la optimización exacta, tales como las heurísticas o metaheurísticas, que permitan estar lo más cerca posible del óptimo en tiempos de computación más cortos. Además, se podrían considerar demandas estocásticas y el manejo de productos perecederos, entre otros.

The present work sought to identify in the PR - Mathematics students' testimonies their understandings of mathematical literacy and competencies when planning and developing mathematical modeling (MM) activities. For this, we intended to answer the following guiding question: What understandings of the favoring of mathematical literacy competencies are manifested by math residents when they develop MM activities? Data production was through a training course with math residents of a public university of the state of Paraná on MM and the competencies of mathematical literacy. The analysis of the data was done interpretively based on the guiding issue. Concerning the results, three categories were evidenced: i) Development of mathematization; ii) Possibilities to formulate, employ, and interpret/evaluate; iii) Development of contents and concepts from different areas of knowledge. This study, in addition to contributing to prospective teachers' education regarding knowledge of mathematical literacy competencies and the contributions of the MM in this process, also proved to be aligned with the objectives of the PR as a professional qualification program for prospective teachers. and interaction between the university and basic education. [ABSTRACT FROM AUTHOR]

The article addresses the mathematical training for engineers, who require new skills to face social challenges and demands, which increasingly revolve around STEM (science, technology, engineering and mathematics). The literature shows the importance of integrating STEM, from the first levels, using mathematical modeling as a bridge between disciplines, to prepare them in the study of problems, solutions and proposals that respond to the needs of the external environment. The objective was to characterize the STEM skills of first-year engineering students, when they integrate knowledge in solving real cases, using mathematical modeling as the basis of the learning process, in collaborative workspaces. A didactic sequence was designed, in algebra and calculus topics, using the case method as a teaching strategy. The methodology was quantitative, through content analysis of their productions. Four engineering college careers participated (civil, industrial, informatics and construction), where a random sample was selected, corresponding to students from informatics and construction. Descriptive statistics, inferential statistics and main components were used in the data analysis. The main results showed that students exceed, on average, the level of competent in STEM skills, but continue to present weaknesses in: interpreting mathematical solutions, projecting the model and designing solutions for engineering, which is attributed to difficulties in representing in 3D, applying geometric properties. The above, was verified by the lack of association between technological and engineering skills, to integrate knowledge. [ABSTRACT FROM AUTHOR]

El artículo analiza los problemas que surgen al determinar la temperatura en la región del punto de cátodo en las brechas de chispa protectoras en miniatura. El principio de modelado se utiliza para estudiar el campo de temperatura en el electrodo de separación de chispas. Un modelo matemático del proceso se compila sobre la base del equilibrio de potencia que entra en el punto del cátodo y su eliminación dentro del cátodo debido a la conductividad térmica. Se presenta una solución numérica de la ecuación de calor no lineal obtenida con condiciones límite inhomogéneas por el método de diferencia finita. Los autores compararon las temperaturas encontradas en el punto cátodo para los metales de los grupos cuarto y quinto de la Tabla Periódica de Mendeleev con los correspondientes puntos de fusión de los metales seleccionados. Se obtuvo una correlación completa entre estas temperaturas. Se ha realizado la simulación de procesos térmicos en la región del punto cátodo en el electrodo de aleación 42NA-VI. Los resultados se presentan en forma de diagramas.

A review of the different mathematical methodologies for calculating energy efficiency in boilers was carried out in this work, considering both the methods included in standards and the proposals and applications published in research works. The classification was delimited in analytical methods, mechanistic modeling, and empirical modeling; moreover, the main equations for each of the methodologies are presented, which allows building a compilation that is expected to be useful for a first approach to the subject. It is displayed that those mechanistic models are used to evaluate subsystems or specific cases that require a high level of detail, while analytical models are used to make a first approximation to the systems described, and empirical models stand out in terms of their use at the industrial level if there is access to a starting database to adjust them. [ABSTRACT FROM AUTHOR]

This article stems from the hermeneutics we carry out of what is revealed in the categories that emerged from the first author's dissertation under the guidance of the second. At that moment, our interpretation addressed how the previous conceptions of a group of teachers operated when they met with the training in Mathematical Modeling according to their notions about different nuclei of ideas. At this moment, we took an inverse path, noticed the different ways those conceptions operated and pointed out the aspects of these nuclei of ideas that converged to this way of operating, in other words, we carried out a meta-analysis of the emerging categories in the dissertation, from which we categorized it into two major nuclei. In this sense, we carried out qualitative research under a phenomenological approach conducted by the question: What is shown of the teachers' previous notions for their continuing education in Mathematical Modeling? The interpretative act leads us to say that the teachers' previous conceptions point a way forward so that the continuing education in Mathematical Modeling achieves its objectives, i.e., the adoption of Mathematical Modeling by basic education teachers. [ABSTRACT FROM AUTHOR]

En este artículo se describe la metodología empleada en la asignatura “Análisis y Simulación de Procesos”, del grado en Ingeniería Química, para el modelado de procesos reales de parámetros distribuidos, discretización del sistema de EDPs resultante empleando el Método de las Líneas (MOL) y posterior simulación con Matlab. La innovación aquí expuesta se basa en la utilización de unas plantillas-guía que el profesor ha creado con Matlab para que los alumnos puedan afrontar con facilidad estos procesos complejos, así como el análisis e interpretación de los resultados obtenidos.

This research study aims to model the transformation process via plasmids of a population of antibiotic sensitive Salmonella enteric and antibiotic resistant Escherichia coli. The mathematical model is validated with experimental data obtained in vitro. Two mathematical models are formulated: 1) before and 2) after transformation via plasmids. The parameters for the model were estimated by using the genetic algorithm method. This allowed performing numerical simulations adjusted to the data to predict population dynamics for the two bacterial strains. The results obtained with the mathematical models revealed that plasmid transformation rate played a fundamental role in plasmid-mediated antibiotic resistance. It is concluded that the method used for parameter estimations allowed to accurately approximate population growth rates, elimination rates caused by antibiotics, and substrate degradation rates, which contributed to improving the understanding of plasmid-mediated antibiotic resistance. [ABSTRACT FROM AUTHOR]

A nivel mundial se considera a la tuberculosis (TB) como una enfermedad de gran importancia en la salud pública con grandes impactos socioeconómicos, presentando elevadas tasas de incidencia y mortalidad. El modelamiento matemático en el complejo CD-Mtb (Células dentríticas-Mycobacterium tuberculosis) ha sido poco estudiado, lo que representa un problema de investigación que se puede abordar con los avances actuales sobre el modelamiento en escalas moleculares, siendo "el modelo receptor-ligando con representación de estados" el más recomendado para abordar esta dinámica. Adicionalmente, la importancia de estudios en este campo radica en la predicción que permitiría efectuar la modelación en asociación al desarrollo de un estadio de Tb activa o latente. Teniendo en cuenta lo anterior, en esta investigación se enfocó en determinar los principales receptores que se acoplan con el ligando manosa en el proceso molecular de reconocimiento, además de formular a partir de la literatura disponible, una red bioquímica que acople la interacción molecular entre las células dendríticas y el patógeno Mtb en las vías de señalización que implican el reconocimiento de la manosa por los receptores de células dendríticas (DC-SIGN, TLR4, de TLR9, TLR2, MR, Dectin-2, Mincle, FcRy, Dectin-1, SIGNR-3, CR3, SR, Langerin). Se espera que a partir de esta red se desarrollen modelos matemáticos mediante sistemas de ecuaciones diferenciales, esta modelación permitirá manipular variables y parámetros, con el propósito de contestar preguntas acerca de las posibles interacciones mediadas entre doce receptores celulares y el ligando manosa.

This article aims to present the perceptions of a group of basic education mathematics teachers regarding the teaching strategy called application of models and highlight its relationship with mathematical modelling in the educational context. This study is an excerpt of a doctoral research in science and mathematics education. After giving the participants a questionnaire on the subject, we analysed their responses based on the discursive textual analysis, which pointed out six different ways of perceiving the application of models, according to the emerging categories of their reports. We also found a close relationship between the application of models and mathematical modelling, which may favour the classroom modelling practice of the teachers, who still feel insecure about its implementation. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Gestão & Tecnologia is the property of Revista Gestao & Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Gestão & Tecnologia is the property of Revista Gestao & Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents a research that aimed to analyze the results of an activity that tried to understand, through mathematical modeling, the speedometer operation of a moving car. The activity was applied to a 7th grade elementary school class in a school in southern Bahia, built on a student's question: "How do car speedometers measure distance and speed when it's moving?" The methodology for analysis of student productions was qualitative. To develop the activity, the students were divided into groups of four members, during the development, was used string and ruler to construct a cardboard caliper to develop the activities. Each group measured the diameters and the circular length of the packages and calculated the value of pi. To build the model, the students simulated how many times a package rotated to cover a distance of four meters. The results showed that these students were able to make hypotheses, make measurements to obtain data, make calculations and make decisions. [ABSTRACT FROM AUTHOR]

The coffee berry borer, Hypothenemus hampei, is one of the plagues with the highest incidence and affectation in the coffee plantation. Colombia is a region that promotes the growth and infestation of this plague. The infestation is due to several factors such as Colombia’s climate, geographic location and continuous coffee production. Coffee production is one of the most important agricultural activities in the country. Therefore, it is important to carry out studies concerning the dynamics of the coffee borer. For this reason, this article adapts the behavior of the coffee borer with an epidemiological model type SIR proposed by Kermack y Mckendrick. This model and the final size relation (proposed by Castillo Chavez) will be used to estimate the coefficient that represents the infestation of the plague in terms of the other parameters involved in the dynamic. Besides, different numerical simulations were done in Matlab environment by changing the values of the parameters of the dynamic system.

El propósito de este trabajo es mostrar una forma de visualizar mejor un modelo matemático a través de redes semánticas a fin de obtener una vista gráfica de las relaciones entre los componentes del problema que se modelará. Un modelo matemático es una descripción de un sistema que usa lenguaje y conceptos matemáticos. El proceso de desarrollo de un modelo matemático se denomina modelación matemática. La idea principal es usar redes semánticas para hacer la conexión entre los elementos involucrados en el modelado, por ejemplo, los conceptos, operadores y todas las características posibles de los objetos que intervienen en sus procesos y eventos en un fragmento de la realidad para el problema en mano. La construcción de modelos matemáticos a través de redes semánticas parece ser más evidente en el sentido de que las relaciones de los diferentes componentes del sistema con el modelo serán más incuestionables; como una consecuencia, las redes semánticas pueden ayudar a comprender mejor cómo la modelación matemática de un fenómeno físico de ingeniería o de otra área del conocimiento puede llevarse a cabo más fácilmente ya que la red semántica describe claramente las relaciones de objetos y conceptos del fenómeno físico de ingeniería o problema que será modelado.

En este trabajo se resolvió numéricamente el secado de Café Pergamino (género coffea, especie arábica, variedad castillo) a través de la resolución de los balances microscópicos de energía y materia. En el modelado fueron consideradas condiciones convectivas que tienen en cuenta el efecto del flujo de aire en la geometría 3D del grano de café. Para la transferencia de energía, se utilizó la ley de Fourier y para la transferencia de materia la ley de Fick, ambas en estado no estacionario. Con el propósito de incorporar el efecto de las microondas sobre los granos de café, se incorporó una fuente de calor constante. La validación fue realizada obteniendo buena concordancia entre los datos experimentales y las simulaciones.

The learning of scientific concepts does not occur spontaneously. The school should organize moments in which students are placed in learning situations to handle such concepts. The objective is to present and discuss the hypothesis that mathematical modeling constitutes an adequate strategy to put the student in activity. More specifically, it is proposed that mathematical modeling can promote student activity, leading to the development of psychological processes aimed at creating meaning and motivation for learning in the initial and final years of Elementary School. To support the argumentation, it is reported a research in which the strategy was used with 9th year's students of a school in São Lourenço do Oeste, Santa Catarina, Brazil. [ABSTRACT FROM AUTHOR]

This article presents research results obtained by the authors in the modeling of the performance indicators of the operation of biomass gasification facilities with helped by non-linear regression techniques, based on the classification of the information derived from the systemic analysis of the operation of these facilities. Some bibliographical studies of the previous research works are carried out, linked to the mathematical modeling of these facilities by the different techniques reflected in the specialized literature. A 3N experimental plan is made with three replicas, from which four non-linear regression models, corresponding to the respective performance indicators, are elaborated using models linearization techniques, with satisfactory results from their evaluation based on the regression coefficients and standard errors foreichhornia crassipes, oryza sativa and wood, used as biomass. The experimental installation and the acquired data acquisition system are described. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Investigaciones Agroindustriales is the property of Revista Colombiana de Investigaciones Agroindustriales del Centro Agropecuario Sena Buga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The target of this paper is to develop and validate a mathematical model to determine the center of mass' position and orientation of a mobile robot (NXT LEGO Kit 2.0). The model takes into account input voltage applied to wheel's servomotors and is formulated using dynamic and kinematics of the robot with a Lagrangian mechanics approach. Experimental results are obtained using the so-called Tracker software. Subsequently, data is processed using a t-student test, comparing experimental data with simulation results, which are obtained executing the model in Matlab-Simulink. As a result, the mathematical model accurately describes the behavior of the robot's center of mass. [ABSTRACT FROM AUTHOR]

Existe una amplia gama de sistemas CAD destinados a modelar objetos tridimensionales. Basados en una creación y transformación intuitiva de objetos geométricos básicos, el fundamento matemático de estas herramientas es generalmente desconocido por sus usuarios. La incorporación de las mismas en el aula de Matemáticas es una pieza clave para lograr captar la atención del alumnado de aquellas titulaciones universitarias en las que los sistemas CAD no sólo son atrayentes, sino que son además de suma importancia para la futura vida profesional. El presente artículo trata acerca de la experiencia docente llevada a cabo en este sentido durante los últimos cinco años en el Grado de Ingeniería de Edificación de la Universidad de Sevilla. La búsqueda metodológica de modelos matemáticos que les permita construir virtualmente edificios reales ha mejorado no sólo el proceso de enseñanza-aprendizaje, sino también su interés en la materia y su rendimiento académico. Un recorrido virtual a través de sus construcciones es una perfecta excusa para tratar también el fundamento matemático en los que se basan los mismos.

The main purpose of this research is to develop the Mathematical Modeling of a Fixed Wing Type Unmanned Aerial Vehicle Category Mini Class II. It will be supported theoretically by authors such as Valavanis, K (2007), Hernández, Fernandez y Baptista (2003), and Ljung (1991) for the variable of mathematical model study of an unmanned aerial vehicle. The research is descriptive, with a nonexperimental design, the population and case study was defined by a unit of analysis which was a Cessna 182 Fixed Wing Aerial Platform under simulation with the Clear View RC program. The methodology to be used in the research with 4 phases: (1) Identify the dynamic variables that govern the altitude of an unmanned aerial vehicle through a description of the input, output and constant variables that influence the flight of an aircraft. fixed wing, (2) Establish the experimental scenarios to study the flight mode. defined by flight maneuvers such as ascent, descent, straight flight and others, (3) Determine the parametric models using flight data acquired by simulation that allow us to represent mathematical models such as ARX, ARMAX, OE, BJ and non-linear which best suit the behavior of the unmanned aerial vehicle and (4) Validate the selected mathematical models to guarantee the reliability of the results. Which will allow to emulate the operability of the system obtaining stability in the maneuvers of flight linear and nonlinear models of superior degree. It is recommended for a future study the testing of the models obtained together with different control methods to test them on real flights with fixed wing vehicles and even acquire real flight data by means of sensors and / or coupled data acquisition devices to the unmanned aerial vehicle, with which to adjust and select better mathematical models [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciencia Administrativa is the property of Universidad Veracruzana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)