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Métodos de detecção de mudança de uso e cobertura do solo para monitoramento ambiental
(Universidade Federal de São Carlos, 2022-06-09) Germano, Aline Delfino; Valente, Roberta Averna; https://lattes.cnpq.br/1582627535733911; https://lattes.cnpq.br/5739783500252918
Forest monitoring is currently indispensable for environmental planning. Through it, it is possible to detect and spatialize changes in land use and cover, becoming a tool for decision-making. In this context, the general objective of the study was to evaluate change detection methods (DM), which support the identification of changes in land use and cover in agricultural landscapes. The study was carried out in the Sarapuí river basin (SP, Brazil), using images from Landsat 5 and 8 satellites, in four different years. Three DM methods were evaluated, being them by normalized vegetation index (DMNDVI), by direct image difference (DMDID) and by change vector analysis (AVM), with and without radiometric and atmospheric corrections. Subsequently, a supervised classification of objects was performed and the respective DM thresholds were obtained. It was verified, using the Z test, that the methods differ statistically, except when the methods with and without correction are compared. Therefore, to define the most appropriate method, the methods were qualified by false positives and false negatives, and the DMNDVI presented better results. With the delimited areas of change, the intersection with the current use and land cover and with the priority areas for forest conservation in the study area was carried out. It was found that in the last thirty years, 22% of the total area of the basin suffered, at some point, changes in its use and soil cover, and in about 6.14% of its total area there was an increase in vegetation and in 15.97% loss of this coverage. In general, it is concluded that the DMNDVI method presents better results, helping in the decision-making process to identify areas for the payment of environmental services, that is, indicating areas where there was a gain in vegetation
Controle de vibrações induzidas pelo vento por alteração do padrão superficial em uma viga cantilever
(Universidade Federal de São Carlos, 2022-06-09) Paladini, Andre Luis Aguiar; Franco, Vitor Ramos; https://lattes.cnpq.br/4590258470207467; https://lattes.cnpq.br/4939459137809627
In the present work, the study of an aeroelastic problem referring to cantilever beams with surface notches exposed to wind is presented, as well as a design of a control system whose purpose is to maintain a desired vibration level for one of the beams, by the action of a bulkhead in exposing its carved surface, given the variation in wind speed. For this purpose, 17 types of surface were proposed and compared, through an analysis of structural dynamics via experimental impact tests and theoretical models validated by their tests, in order to determine the purely structural influence related to the presence of each type of notch on the surface. Next, the beams were subjected to an experiment in which an aerodynamic excitation was provided by a centrifugal fan capable of controlling the wind speed. Thus, the vibration for each beam was measured and compared in terms of their RMS values associated with the vibration signal power, as well as the power distributions along the frequency band. In this way, the beam with superficial notches with the highest RMS value was selected and subjected to a new test, which had a bulkhead that gradually covered a portion of its surface, in fixed distance steps. In this experiment, the same analyzes regarding the power and its RMS values were performed, however, by varying the bulkhead positions and the wind speed. A function that correlates the RMS values with the wind speed and the instantaneous position of the bulkhead was obtained from the interpolation of the results in order to contribute to the control system plant model, which also relied on the results of the analysis of structural dynamics. With the plant model determined, a control system was designed based on two PID controllers in cascade, with a loop to control the position of the actuation system, referring to the position of the bulkhead, and another, to control the vibration levels, given an RMS value. The results for the control system were simulated computationally, with the help of MatLab® and Simulink®, and responses were obtained that stabilized themselves around the reference value, given the variation in wind speed. It was concluded that, by obtaining theoretical and experimental information about the proposed aeroelastic problem, it was possible to carry out an application of the studied concepts by the design of a control system capable to stabilize the vibration levels of a cantilever beam.
Bayesian inference for term structure models
(Universidade Federal de São Carlos, 2022-06-09) Martins, Thomas Correa e Silva; Diniz, Márcio Alves; https://lattes.cnpq.br/8948404469003829; Montoril, Michel Helcias; https://lattes.cnpq.br/9993502064983663; https://lattes.cnpq.br/8097297073113160
We explore recent advances in Bayesian methods in order to estimate the Vasicek, CIR and dynamic Nelson-Siegel (DNS) models for term structure of interest rates. The models are specified as state space time series. The main goal of this work is assessing and comparing the forecasting abilities of each model with respect to the observed data via mean absolute error. When estimated with synthetic simulated datasets, the models are able to successfully recover the latent vectors. As for the forecasting abilities, the multifactor models generally deliver the best predictions. The relevance of this work lies in integrating novel computational techniques for Bayesian inference with canonical models from the field of financial economics. Several aspects of both fields are discussed throughout the text.
Gestão democrática participativa: uma análise sobre os saberes dos diretores escolares
(Universidade Federal de São Carlos, 2022-06-09) Silva, Rita de Cássia Rosa da; Luiz, Maria Cecília; https://lattes.cnpq.br/7425361719028650; https://lattes.cnpq.br/7073133148661446
La discusión sobre la gestión escolar, en la actualidad, ha sido realizada por diferentes académicos, con el foco en la democratización y autonomía escolar, así como en lograr una educación de calidad para sus estudiantes. A partir de esta premisa, el objetivo de esta investigación es analizar los saberes de los directores de escuela en relación a la gestión democrática y participativa. Para ello, se analizó la participación de directores de escuela que participaron en el curso de formación para directores mentores de 10 estados brasileños, realizado en alianza entre la Universidad Federal de São Carlos y la Secretaría de Educación Básica del Ministerio de Educación. La base teórica se basa en el conocimiento de los directores de escuela, en la perspectiva de la teoría de la Relación con el Conocimiento de Bernard Charlot (2000). La metodología utilizada fue la investigación cualitativa con enfoque exploratorio, a partir del análisis de las actividades reflexivas realizadas por estos directores de escuela, en el recorte de una de las salas temáticas del curso, basado en la metodología de investigación de Charlot. Se concluyó que los directores encuestados tenían dificultad para llevar definiciones y acciones sobre el colegiado de la escuela, y sus declaraciones eran contradictorias, eligiendo el colegiado ya sea como un "brazo derecho", a veces como un espacio burocrático de acciones que "nadie quiere participar" . Estas contradicciones revelan que el director se encuentra ante la necesidad de trabajar con órganos colegiados y no sabe cómo hacerlo. Estos no entienden efectivamente lo que sería el colegiado, cuáles serían sus funciones, sus roles dentro de la escuela. Con la necesidad de aprender de la posición social objetiva de ser director, los órganos colegiados se han convertido en un tema que amerita una mirada específica para comprender su funcionamiento, y con eso, el director tiene la posibilidad de presentar su posición social subjetiva, porque es desde su posición en el rol de director que la participación de la comunidad en la toma de decisiones de la escuela puede ser efectiva o mantenerse sólo como una presencia física. Es desde la posición social subjetiva del director de la escuela que su gestión se vuelve democrática, rompiendo con un autoritarismo aún presente en su identificación o perpetuando este autoritarismo. Por el contrario, como se ha hecho, significa tener una participación que dificulta la efectividad de la gestión democrática participativa, ya que los sujetos forman parte del colegiado, pero no son participantes activos, produciéndose así efectos negativos por la pasividad de los mismos. del grupo, y trayendo limitaciones a las tomas, decisiones y resoluciones ante los desafíos y dificultades escolares.