Abstract Introduction. Climate change adaptation measures require informed decision-making. However, small-scale agriculture shows low rates of technology adoption due to cost and lack of connectivity. Objective. To evaluate three low-cost prototypes of small-scale agriculture devices for soil moisture measurement in different soil textures, as well as to determine the respective calibration equations, and the effects of electrical conductivity and temperature on moisture measurement. Materials and methods. Three measurement and recording prototypes for soil moisture were evaluated in soils with variations in clay/sand content and electrical conductivity in productive plots at Zamorano University in Honduras and a demonstration farm in Popayán, Colombia during the first quarter of 2022. Commercial sensors were used as a reference to compare the performance of the prototypes through regression analysis of hourly sensor readings over 90 days. Electrical conductivity (dS/m) and temperature variables were collected to determine their influence on moisture reading accuracy. Results. The soil moisture measurement devices showed better performance in soils with lower sand content. The measurement from the devices overestimated moisture readings by 0.19 to 0.52 percentage points for each additional degree of soil temperature. Additionally, for each additional dS/m of electrical conductivity, the reading needed adjustment by 8 to 55 percentage points. Conclusions. Prototype A was the most accurate device, while prototype B was the most precise compared to commercial sensors. Soil moisture devices performed best in soils with lower sand content. The three models evaluated performed best in loam soil with a medium clay content.

Resumen Introducción. Las medidas de adaptación al cambio climático requieren de la toma de decisiones informadas. Sin embargo, la agricultura de pequeña escala muestra bajas tasas de adopción de tecnologías por su costo y falta de conectividad. Objetivo. Evaluar tres prototipos de dispositivos para agricultura de pequeña escala y de bajo costo para medir humedad de suelo en diferentes texturas, así como determinar las respectivas ecuaciones de calibración y los efectos de conductividad eléctrica y temperatura en la medida de humedad. Materiales y métodos. Se evaluaron tres prototipos de dispositivos de medición y registro de humedad de suelo, en suelos con diferencial en contenido de arcilla/arena y conductividad eléctrica en parcelas productivas de la Universidad Zamorano, en Honduras; y Finca demostrativa en Popayán, Colombia, durante el primer trimestre del 2022. Se tomaron como referencia sensores comerciales para la comparación del desempeño de los prototipos, mediante análisis de regresión de las lecturas por hora de los sensores durante 90 días. Se recolectaron las variables de conductividad eléctrica (dS/m) y temperatura para determinar la influencia en la precisión de la lectura de humedad. Resultados. Los dispositivos de medición y registro de humedad presentaron un mejor desempeño en suelos con menor contenido de arena. La medición de los dispositivos sobrestimó entre 0,19 y 0,52 puntos porcentuales la lectura de humedad por cada grado adicional de temperatura del suelo, y que por cada dS/m adicional de conductividad eléctrica la lectura se debe ajustar entre 8 y 55 puntos porcentuales. Conclusiones. El prototipo A fue el dispositivo más exacto, mientras que el prototipo B fue el más preciso, con respecto a los sensores comerciales. Los dispositivos de humedad presentaron un mejor desempeño en suelos con menor contenido de arena. Los tres modelos evaluados obtuvieron el mejor desempeño en suelo franco con contenido medio de arcilla.

Resumen El certificado es una evidencia de participación en un proceso y se cree que cualquier persona que posea uno tiene un requisito previo para manejar todo aquello para lo que este califica. Sin embargo, la impresión podría fallar, si el certificado se hubiera obtenido tomando atajos. (Objetivo) En este documento se desarrolló un modelo compartimental para cuantificar los factores que podrían poner en duda la autenticidad de un certificado, mediante el examen de la compensación entre el estándar académico y las tasas de reprobación, en el contexto de las instituciones de educación terciaria en Nigeria. (Metodología) El modelo se demostró válido utilizando algunos amplios teoremas matemáticos. Se derivaron los equilibrios para dicho método y el umbral para un rendimiento académico aceptable. El análisis de estabilidad se llevó a cabo empleando la teoría de la estabilidad de ecuaciones diferenciales, basada en el umbral de rendimiento académico ace ptable obtenido. (Resultados) Los resultados teóricos del modelo fueron validados por medio de simulaciones numéricas y los de las simulaciones vincularon la tasa de reprobación aceptable con el rendimiento académico que cayó por debajo del umbral del estándar establecido por las instituciones. (Conclusiones) La implicación política del resultado es que el aumento en la oferta de graduados calificados en los mercados laborales de Nigeria, así como la reducción en la tasa de desempleo, son una función del mantenimie nto de los estándares académicos.

Resumo O certificado é uma prova de participação em um processo e acredita-se que quem o possui tem como pré-requisito realizar tudo para o qual o referido certific ado o qualifica. No entanto, a impressão poderia falhar se o certificado tivesse sido obtido através de atalhos. (Objetivo) Neste artigo, foi desenvolvido um modelo compartimental para quantificar fatores que poderiam pôr em dúvida a autenticidade de um certificado, examinando o compromisso entre o padrão académico e as taxas de reprovação no contexto de instituições terciárias referenciadas na Nigéria. (Metodologia) O modelo foi provado válido usando alguns teoremas matemáticos amplos. Os equilíbrios para o modelo e o limite para desempenho acadêmico aceitável foram derivados. A análise de estabilidade foi realizada utilizando a teoria da estabilidade de equações diferenciais com base no limite de desempenho acadêmico aceitável derivado. (Resultados) Os resultados teóricos do modelo foram validados por meio de simulações numéricas e os resultados das simulações relacionaram a taxa de reprovação aceitável com o desempenho acadêmico que ficou abaixo do limite do padrão estabelecido pelas instituições. (Conclusões) A implicação política do resultado é que o aumento da oferta de licenciados qualificados nos mercados de trabalho nigerianos, bem como a redução da taxa de desemprego, é uma função da manutenção dos padrões académicos.

Abstract A certificate is evidence of participating in a process, and anyone who holds a certificate is believed to have the prerequisites necessary to handle what the certificate qualifies them for. However, this perception might be incorrect if the certificate has been obtained by taking shortcuts. (Objective) In this paper, a compartmental model was developed to quantify factors that could put the authenticity of a certificate in doubt by examining the trade-off between academic standards and failure rates in the context of tertiary education institutions in Nigeria. (Methodology) The model was validated using several mathematical theorems. Equilibria for the model and the threshold for acceptable academic performance were derived. Stability analysis was carried out by using the stability theory of differential equations based on the derived acceptable academic performance threshold. (Results) The theoretical results for the model were validated through numerical simulations, and the results from the simulations linked acceptable failure rates to academic performance falling below the threshold of the institutions’ standards. (Conclusions) The policy implication of the result is that an increase in the supply of qualified graduates into Nigeria’s labor markets, as well as a reduction in the rate of unemployment, is a function of maintaining academic standards.

ABSTRACT The purpose of this research is to propose a model for the design of work environments in the SMEs Bogotá Metropolitan Area, taking as a guide the methodology of Kansei Engineering, with the support of instruments such as the survey and the semantic differential test, the neural networks (multilayer perceptron) for its validation. A questionnaire is elaborated with the support of experts, and a pilot test is carried out to improve and evaluate the relevance of the questions. Using the SPSS Software, the statistical analysis was performed, applying the normality tests, performing Spearman correlations, principal component analysis, and linear regression to the resulting equations to understand the relationships between the studied perceptions and the work environment in general. Subsequently the multilayer perceptron was used as a neural network model to validate the relationships between the proposed variables and perceptions, allowing at the same time to determine the importance of the emotional dimensions in the design of work environments, from which it was possible to conclude that the application of Kansei Engineering for the design of work environments is possible.

RESUMEN El propósito de esta investigación es proponer un modelo para el diseño de ambientes laborales en las Pymes Bogotá Área - Metropolitana tomando como guía la metodología de la Ingeniera Kansei, con el apoyo de instrumentos como la encuesta y la prueba de diferencial semántico, las redes neuronales (perceptrón multicapa) para su validación. Se elabora un cuestionario con cuestionario con el apoyo de expertos, al que se le realiza una prueba piloto para mejorar y evaluar la pertinencia de las preguntas. Haciendo uso del Software SPSS se realizó el análisis estadístico, aplicando las pruebas de normalidad, realizando correlaciones de Spearman, análisis de componentes principales, regresión lineal a las ecuaciones resultantes para entender las relaciones entre las percepciones estudiadas y el ambiente laboral en general. Posteriormente, hizo uso del perceptrón multicapa como modelo de redes neuronales para validar las relaciones entre las variables y percepciones propuestas permitiendo a su vez determinar la importancia de las dimensiones emocionales en el diseño de ambientes laborales, a partir de lo cual se pudo concluir que es posible la aplicación de la Ingeniería Kansei para el diseño de ambientes laborales.

RESUMO O objetivo desta pesquisa é propor um modelo para o projeto de ambientes de trabalho em PMEs da Região Metropolitana de Bogotá, usando a metodologia da Engenharia Kansei como guia, com o apoio de instrumentos como a pesquisa e o teste de diferencial semântico, e redes neurais (perceptron multicamadas) para validação. É elaborado um questionário com o apoio de especialistas, que é testado como piloto para melhorar e avaliar a relevância das perguntas. A análise estatística foi realizada com o software SPSS, aplicando testes de normalidade, correlações de Spearman, análise de componentes principais e regressão linear às equações resultantes para entender as relações entre as percepções estudadas e o ambiente de trabalho em geral. Posteriormente, utilizou-se o perceptron de múltiplas camadas como modelo de rede neural para validar as relações entre as variáveis e as percepções propostas, permitindo, por sua vez, determinar a importância das dimensões emocionais no projeto de ambientes de trabalho, a partir do qual foi possível concluir que é possível aplicar a Engenharia Kansei ao projeto de ambientes de trabalho.

Abstract A comparison is established between the traditional design of the linear economy and that of a circular economy through the proposal of heuristic dynamic models based on non-linear systems of ordinary differential equations. It was found that, for critical values of the control parameter, natural resources, through an Andronov-Hopf bifurcation, the circular economy model self-organizes out of thermodynamic equilibrium, and exhibits high complexity, robustness, resilience and adaptability, which was verified by evaluating the Shannon entropy of their trajectories. Finally, it was shown, through an ansatz, that the circular economy model shows greater efficiency compared to the traditional linear model.

Resumen Se establece una comparación entre el diseño tradicional de la economía lineal y el de una economía circular a través de la propuesta de modelos dinámicos heurísticos basados en sistemas no lineales de ecuaciones diferenciales ordinarias. Se encontró que, para valores críticos del parámetro de control, los recursos naturales, a través de una bifurcación de Andronov-Hopf, el modelo de economía circular se autorganiza fuera del equilibrio termodinámico, y exhibe una alta complejidad, robustez, resiliencia y adaptabilidad, lo cual se verificó a través de evaluar la entropía de Shannon de sus trayectorias. Finalmente, se mostró por medio de un ansatz, que el modelo de economía circular muestra una mayor eficiencia en comparación con el modelo tradicional lineal.

Abstract In forestry, accurate estimation of timber volume is essential for forest management in temperate forests. The objective of the present research was to generate equations of the total tree volume (Vtt), stem volume (Vs), and stem profile for Pinus ayacahuite, Pinus leiophylla, Pinus hartwegii, Pinus montezumae, Pinus patula, Pinus pseudostrobus, Pinus teocote, Abies religiosa and Quercus sp. in productive landscapes of a temperate ecosystem in the state of Puebla, Mexico. A sample of 1 676 trees was collected by destructive sampling. Based on the dendrometric type, the Vs, Vtt, and crown volume (Vc) were obtained. The volume of branches and twigs with diameters less than 5 cm was estimated using a xylometer and the Berkhout nonlinear model. The Schumacher-Hall model was fitted for the Vtt and the Vs with weighted regression in order to correct for heteroscedasticity. The Biging function was used to describe the stem profile, fitted with nonlinear generalized least squares to correct for autocorrelation. The goodness of fit of the equations are above 96 %, and the bias is below 0.04 m3. The statistical results show that the differential equation system predicts with certainty the Vtt, Vs, as well as the taper of commercial species in the temperate forests of Puebla, Mexico.

Resumen En silvicultura, la estimación precisa del volumen maderable es fundamental para el manejo forestal en bosques templados. El objetivo de la presente investigación fue generar ecuaciones de volumen total árbol (Vta), volumen fustal (Vf) y perfil del fuste para Pinus ayacahuite, Pinus leiophylla, Pinus hartwegii, Pinus montezumae, Pinus patula, Pinus pseudostrobus, Pinus teocote, Abies religiosa y Quercus sp. en paisajes productivos de un ecosistema templado en Puebla, México. Mediante un muestreo destructivo se recolectó una muestra de 1 676 árboles. Con base en el tipo dendrométrico se obtuvo el Vf, Vta y volumen de copa (Vc). Con un xilómetro y el modelo no lineal de Berkhout se estimó el volumen de ramas y ramillas con diámetros menores a 5 cm. Para Vta y Vf se ajustó el modelo Schumacher-Hall con regresión ponderada para corregir la heterocedasticidad. La función de Biging se usó para describir el perfil fustal, ajustado con mínimos cuadrados generalizados no lineales para corregir la autocorrelación. La bondad de ajuste de las ecuaciones fue superior a 96 % y un sesgo menor a 0.04 m3. Los resultados estadísticos muestran que el sistema de ecuaciones diferenciado predice con certidumbre el Vta, Vf y ahusamiento de las especies maderables comerciales en los bosques templados de Puebla, México.

Resumen: El método de disparo es una técnica iterativa que usa velocidad de disparo para obtener una solución óptima. El propósito de la investigación es verificar la eficacia de las iteraciones de Newton de orden 3 adaptadas y acopladas a RK4, en el método disparo. Se realizó un experimento numérico con ejemplos mediante el método de disparo en las ecuaciones diferenciales ordinarias no lineal de orden 2, y se obtuvo velocidades de disparo y errores en cada iteración. Los resultados obtenidos sobre velocidades finales fueron satisfactorios con las iteraciones NW, NWO3-1, NWO3-2 y NWO3-3 aplicadas al método de disparo y de los cuales, NWO3-2 y NWO3-3 tienen alta precisión en los experimentos realizados.

Abstract: The shooting method is an iterative technique that uses shooting speed to obtain an optimal solution. The purpose of the research is to verify the effectiveness of Newton iterations of order 3 adapted and coupled to RK4, in the shooting method. Numerical experiments were performed with examples using the shooting method in nonlinear ordinary differential equations of order 2, and shooting velocities and errors were obtained in each iteration. The results obtained on final velocities were satisfactory with the iterations NW, NWO3-1, NWO3-2 and NWO3-3 applied to the shooting method and of which, NWO3-2 and NWO3-3 have high accuracy in the experiments performed.

Abstract In this work, a nonlinear model is studied based on ordinary differential equations that describe the relationship between the mass of β cells and the secretion of epinephrine. It analyzes the impact of stress associated with the cause of increased blood pressure and glucose levels in the body. The mathematical analysis is based on the appliance of the nonlinear control theory to define the maximum load capacity for each state variable, establishing a bounded positive invariant domain through the Localization of Compact Invariants Sets (LCIS) method. The objective is to determine the effects of epinephrine secretion on the increase of blood glucose levels; therefore, this analysis's results define the necessary and sufficient conditions in which epinephrine raises insulin and glucose levels in the presence of β cells. The interest in studying this type of disease focuses on searching for a treatment or an analysis that guarantees complete control of glucose levels. This work's development and mathematical analysis strengthen current research on insulin-dependent diabetes mellitus around critical epinephrine factors that imply an increase in glucose in the body.

Resumen En este trabajo se estudia un modelo de ecuaciones diferenciales ordinarias no lineales que describe la relación entre la masa de células β y la secreción de epinefrina. Se analiza el impacto del estrés asociado como causante de incremento de los niveles de glucosa en el organismo. El análisis matemático se fundamenta en la aplicación de la teoría de control no lineal para definir la capacidad de carga máxima para cada variable de estado, estableciendo un dominio invariante positivo acotado a través del método de Localización de Conjuntos Compactos Invariantes (LCCI). El objetivo es determinar los efectos asociados a la secreción de epinefrina en el aumento de los niveles de glucosa en sangre; por lo tanto, los resultados de este análisis ayudan a definir las condiciones necesarias y suficientes en las que la epinefrina eleva los niveles de insulina y glucosa en presencia de células β. El interés por estudiar este tipo de enfermedades se enfoca en la búsqueda de un tratamiento o un análisis que garantice un control completo de los niveles de glucosa. El desarrollo y análisis matemático de este trabajo fortalece la investigación vigente de diabetes mellitus insulinodependiente entorno a factores críticos de epinefrina que implican un incremento de glucosa en el organismo.

Abstract: This study examines how the sentiment values in the first part of the book entitled as “Underground” of Fyodor Dostoevsky’s ”Notes from Underground” change from words to sentences to paragraphs. Using the GPT-4 language model, we conducted a descriptive analysis of standardized sentiment values and calculated cumulative binned values of the sentiment trajectories over the text. We then created differential equation models to model the sentiment tones using quantile regression analysis. We show that binned values can reveal a more dynamic and potentially chaotic structure when applied to the cumulative sum of sentiments for word, sentence, and paragraph levels. We model differential equations derived for word, sentence, and paragraph levels via quantile regression. They demonstrate how the rate and acceleration of sentiment change are influenced by their current state and rate of change. In conclusion, this study’s findings are important for enhancing the capabilities of AI-driven chatbots in sentiment analysis, particularly in dissecting and understanding the layered emotional landscapes of literary works.

The problem of a particle subject to a time-dependent driving force plus a linear velocity-dependent friction can be addressed by utilizing the unilateral Fourier transform, despite the presence of derivatives of odd and even order in the differential equation. This technique yields a system of algebraic equations that combine the Fourier sine and cosine transforms. While this method is useless for solving the homogeneous equation, it can be effectively used to obtain an integral representation of the particular solution. Remarkably, this integral representation of the particular solution is expressed in terms of the Green function. This type of exactly solvable problem is relevant for students who are studying mathematical methods applied in the fields of physics and engineering at the undergraduate level, as it can serve as a useful illustration of how unilateral Fourier transforms can be employed to solve problems and to develop an understanding of Green functions, even in introductory calculus courses. timedependent time dependent velocitydependent velocity transform equation Remarkably function level functions courses

This paper approaches a periodic inductor-capacitor circuit with N-coupled loops. Kirchhoff’s voltage and current laws are used in order to obtain N-coupled second-order differential equations. These equations are decoupled by using a standard discrete sine transformation. Then the voltages and currents along the circuit are written as linear combinations of harmonic waves whose normal frequencies were determined. There are N of these frequencies that depend not only on the values of the capacitance and inductance but also, on how these elements are connected. Furthermore, one presents how each normal frequency can be synchronized using external batteries that initially charge the capacitors. Additionally, not only the analytical results are presented, but also, all circuits were simulated, using the free online platform Multisim, to corroborate the analytical calculations. Further, the simulations present a way of exploring the complex subject of coupled oscillations without dealing with all the analytical calculations. Moreover, one explores interferences that produce beats in the oscillating voltages in the circuit. Finally, a general interpretation of how the currents flow in the circuit is presented when a single normal mode is excited. inductorcapacitor inductor capacitor Ncoupled loops Kirchhoffs Kirchhoff s secondorder second transformation determined also connected Furthermore capacitors Additionally simulated Multisim calculations Further Moreover Finally excited

ABSTRACT Understanding of various aerodynamic factors involved in flight trajectories is fundamental to design launch vehicles. First and foremost, computer simulation is an efficient way of predicting its behavior in the movement across the atmosphere. Considering that the available Brazilian version of Analysis, Simulation and Trajectory Optimization Software for Space Applications (Astos) does not simulate a controlled vehicle in six degrees of freedom (DoF), the aim of this article is to complement the Astos outcomes, particularly evaluating the trajectory of a controlled launch vehicle from liftoff to orbit injection, considering the model of rigid body dynamics with a six DoF. This approach carried out with an in-house developed simulator called Scott that simulated a multistage launcher with three flight configurations. In the Scott computer program, a launcher was modeled with differential equations in six DoF, coupled axes attitude control system, and aerodynamic coefficients that changed as a function of Mach number. These features improved the results generated by Astos software for the same configurations and the same initial conditions. Additionally, the results provided by Scott were close to actual vehicle in terms of attitude change and Mach number reached. vehicles foremost atmosphere Analysis (Astos DoF , (DoF) outcomes injection inhouse house program system conditions Additionally reached (DoF

This review aims to provide a comprehensive evaluation of the dynamics of the double pendulum, with a particular emphasis on its chaotic behavior. It examines the complicated and unpredictable behavior of the double pendulum. It highlights the pedagogical value of the double pendulum as it bridges concepts across physics, mathematics, and computer science, providing a tangible demonstration of chaotic dynamics. Numerical methods, such as the 4th-order Runge-Kutta method, estimate solutions to the autonomous Hamiltonian equations that govern a system. We simulate the motion of a double pendulum, enabling the visualization of intricate trajectories and the analysis of emerging patterns with the Python and Fortran programming languages. We discuss the importance of Poincaré’s maps and the Lyapunov exponents in characterizing and quantifying the rate at which trajectories diverge in phase space to elucidate the chaotic nature of the system. The educational significance of the double pendulum is emphasized in teaching key concepts in Classical Mechanics, Differential Calculus, Linear Algebra, and Numerical Methods for solving ordinary differential equations (ODEs). We also explore the interdisciplinary teaching opportunities presented by the double pendulum. physics mathematics science methods 4thorder thorder 4th order th RungeKutta Runge Kutta method system languages Poincarés Poincaré s Mechanics Calculus Algebra ODEs. ODEs . (ODEs) (ODEs

This article explores the use of the Sturm-Liouville operator in the spectral representation of the Green’s function, highlighting its applicability in mathematical physics. We focus on spectral representation as a technique for solving non-homogeneous differential equations, using the eigenfunctions of the Sturm-Liouville operator. We demonstrate the application of these concepts in fundamental problems of electromagnetism, and quantum mechanics, obtaining analytical solutions and revisiting concepts. We highlight the use of Python programming for the graphical visualization of solutions, facilitating the understanding of complex mathematical concepts and offering an intuitive approach to the analysis of physical phenomena. In the final section, we emphasize how the work provides valuable insights for the solution of differential equations and the interpretation of physical phenomena. We conclude by pointing to future work, suggesting an even deeper integration between programming and mathematics in contemporary physics, with the goal of making learning more intuitive. SturmLiouville Sturm Liouville Greens Green s function physics nonhomogeneous non homogeneous electromagnetism mechanics phenomena section

Este artigo explora o uso do operador de Sturm-Liouville na representação espectral da função de Green, destacando sua aplicabilidade em física matemática. Focamos na representação espectral como uma técnica para resolver equações diferenciais não-homogêneas, utilizando as autofunções do operador de Sturm-Liouville. Demonstramos a aplicação desses conceitos em problemas fundamentais de eletromagnetismo e mecânica quântica, obtendo soluções analíticas e revisitando conceitos. Destacamos o uso da programação em Python para visualização gráfica das soluções, facilitando a compreensão de conceitos matemáticos complexos e oferecendo uma abordagem intuitiva para a análise de fenômenos físicos. Na seção final, enfatizamos como o trabalho proporciona insights valiosos para a solução de equações diferenciais e interpretação de fenômenos físicos. Concluímos apontando para trabalhos futuros, sugerindo uma integração ainda mais profunda entre programação e matemática na física contemporânea, com o objetivo de tornar o aprendizado mais intuitivo. SturmLiouville Sturm Liouville Green nãohomogêneas, nãohomogêneas não homogêneas, homogêneas não-homogêneas SturmLiouville. Liouville. quântica físicos final futuros contemporânea intuitivo

Cardiovascular diseases are the leading cause of mortality in the world. The electrocardiogram exam is one of the ways to obtain a diagnosis related to cardiac diseases. The exam consists of recording the electric activity of the heart using electrodes positioned on the arms, legs, and thorax. In this work, we study the McSharry model that is able to mimic the characteristic signals of the electrocardiogram by three differential equations. Considering a noise and a sinusoidal term in the model, we verify that these modifications allow a change to the signal characteristic. We show that is possible to generate electrocardiogram signals similar to those that characterize cardiovascular diseases. We use real exams reported by Sociedade de Cardiologia do Estado do Rio de Janeiro to compare with our simulations. world arms legs thorax work equations simulations

As doenças cardiovasculares lideram a causa de mortalidade no mundo. O eletrocardiograma é uma das formas de obter o diagnóstico relacionado a doenças cardíacas. O exame consiste no registro da atividade elétrica do músculo cardíaco por meio de eletrodos posicionados nos braços, pernas e tórax do indivíduo. Neste trabalho estudamos o modelo de McSharry, que é capaz de reproduzir os sinais característicos do eletrocardiograma usando três equações diferenciais acopladas. Adicionando ao modelo um ruído e um termo senoidal, verificamos que essas modificações permitem alterar a característica do sinal de eletrocardiograma. Mostramos que é possível gerar sinais semelhantes àqueles que caracterizam anomalias no sistema cardiovascular. Utilizamos exames reais reportados pela Sociedade de Cardiologia do Estado do Rio de Janeiro para comparar com os resultados das simulações. mundo cardíacas braços indivíduo McSharry acopladas senoidal cardiovascular simulações

Describing the harmonic motion of a simple pendulum observed from a rotating reference frame necessitates solving the differential equations governing three-dimensional motion in a non-inertial reference frame, which can be a challenging endeavor for newcomers to this subject. However, in this study, we propose a highly didactic and visually accessible approach by considering the rotating reference frame as a matrix transformation. This approach enables a deeper understanding of the origin of Coriolis and centrifugal accelerations, which are responsible for the curved trajectories exhibited by the simple pendulum in a rotating reference frame. threedimensional three dimensional noninertial non inertial subject However study transformation accelerations