Repositório UFSCar
http://repositorio.ufscar.br:80
The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.2024-03-14T01:23:41ZAgroecólogos neorrurais: educação, (re)existência camponesa e desenvolvimento rural sustentável
https://repositorio.ufscar.br/handle/ufscar/19626
Agroecólogos neorrurais: educação, (re)existência camponesa e desenvolvimento rural sustentável
Buoro, Francisco Carvalho
This study qualitatively analyses the practices of six neorural agroecological producers, graduated in Agroecology in two different institutions: the Federal University of São Carlos (UFSCAR) and the Federal Institute of Education, Science and Technology of Southeast Minas Gerais (IFSEMG). The analysis, based on participant observation, discourse analysis and exchange of experiences, covers several aspects, including production, housing, trade, culture, ideology, food, sociability, management, waste management, use of natural resources and access to land. The objective is to highlight the potentialities and challenges in the search for the consolidation of agricultural and rural sustainability, highlighting the central role of education in agroecology, peasant culture and new ruralities in this process. It was possible to verify the central role of education in agroecology, peasant culture and new ruralities in this process through the work of neo-rural agroecologists.
2024-01-10T00:00:00ZControle proporcional de um modelo IS-LM com atuação no ajuste do mercado de moeda
https://repositorio.ufscar.br/handle/ufscar/19625
Controle proporcional de um modelo IS-LM com atuação no ajuste do mercado de moeda
Barbieri, Luigi Reis
In this paper, the proposed study seeks to augment intuition regarding the role of the adjustment of interest rate in the GDP stabilization, by making use of engineering techniques. It is proposed a macroeconomic analysis by means of a dynamic model, with following use of a control mesh in order to reduce the stabilization time of the system. Different sources of instability are applied to the system in order to evaluate the efficiency of the control mesh. Finally, it is used real data from Brazilian macroeconomy taken from IpeaDATA from the period of 2010 to 2019 to also test the control system.
2021-01-13T00:00:00ZMonitoramento da integridade estrutural a partir de sensoreamento de baixo-custo: Investigação de técnicas de inteligência artificial para classificação de danos estruturais
https://repositorio.ufscar.br/handle/ufscar/19624
Monitoramento da integridade estrutural a partir de sensoreamento de baixo-custo: Investigação de técnicas de inteligência artificial para classificação de danos estruturais
Hagihara, Rodrigo Jun
In engineering, a structure is designed considering its possible failure due to damage that occurs over time. In this context, in order to extend the useful life of components, avoid failures and operational problems, periodic maintenance is carried out. Several studies are conducted on maintenance based on real-time monitoring of the state of a structure, anticipating the detection of damage. The high precision and constant dependence on human resources to obtain conclusive parameters makes the process costly. Therefore, the biggest obstacle for monitoring is differentiating between damaged and undamaged structures using low-cost equipment and statistical pattern recognition algorithms. In the present work, supervised learning techniques were used to analyze simulated vibration signals and vibration signals of a structure for correlation with different types of damage. Using MATLAB, ADXL335 accelerometer and ESP-32 microcontroller to monitor the state of a simple two-story structure excited by external impact-type forces, it was possible to extract the natural frequencies and damping coefficients as main attributes for classifying the dimension of the associated damage. . At the end of the study, it was found that the different classifiers Medium Gaussian SVM, Medium KNN, Medium Tree and Linear Discriminant achieved accuracy greater than 85% to highlight the differences between damage conditions. Different performance metrics were analyzed to prove their accuracy, such as: true positive rate, true negative rate, positive predictive values, false discovery rate, false positive rate, ROC curve and AUC. By comparing the results obtained with the structure and simulated signals, the effectiveness of artificial intelligence and the feasibility of using economically accessible instrumentation to monitor structural integrity in small structures were evaluated. Despite the need for a large amount of data to obtain good results, it is believed that the model obtained can contribute to the generation of new algorithms capable of classifying different types of damage to structures.
2023-11-16T00:00:00ZMonitoramento da integridade estrutural a partir de sensoriamento de baixo-custo: projeto e desenvolvimento de bancada experimental integrada a plataforma de computação em nuvem
https://repositorio.ufscar.br/handle/ufscar/19623
Monitoramento da integridade estrutural a partir de sensoriamento de baixo-custo: projeto e desenvolvimento de bancada experimental integrada a plataforma de computação em nuvem
Vasconcelos, João Pedro Castro
Structural Health Monitoring (SHM) has been a widely used tool, as it offers greater longevity to structures. Technologies using vibration as a parameter for this monitoring are proving to be efficient and several research topics in this field are being developed. However, the use of sensors for monitoring structures implies in a high cost, which is the main limitation regarding the feasibility of applying structural integrity monitoring on a larger scale. With the evolution in accuracy and reliability of low-cost sensors and rapid prototyping boards, their implementation in the industry is increasingly being studied. In the current work, a workbench was designed and developed with flexible materials and a simple design, where sensors and a rapid prototyping board were installed, responsible for transmitting the data to a digital platform. Measurements were made on the experimental bench while excited by vibrations, then damage was generated to the bench and new measurements were taken. With this, it was possible to simulate an application of SHM with low-cost sensors and equipment to analyse the behaviour of the data obtained in the proposed damage scenarios. At the end of the study, the established damage indices were sensitive to variations of the damage caused to the bench, demonstrating the potential for an efficient application of the proposed experiment for a structural health monitoring practical model.
2023-03-17T00:00:00Z