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This paper proposes methods for improvement electrical grounding systems performance. There is a intense need for efficient electrical protection systems, to protect people and property against electric currents discharges, thus adding improvements to electrical grounding systems already in use. Based on this principle, this work is divided in: i) soil resistance values variation, due to different...
In this work, it is proposed to calculate the sensitivity of parameters, based on analytical calculation, of repowered system between two electric generators, an induction generator and a synchronous generator, connected to a common bus in permanent regime, subject to a non-linear load. It is proposed a repowered system with simulated data where, based on percentage variations in the base values of...
This work proposes an analytical method for calculating sensitivity index. The proposed method is based on one-at-a-time measurements and calculates the difference between output values and the base solution to define the impact caused by each parameter in the system. The results indicated that the analytical method provides adequate values for the sensitivity index even when the parameters have minor...
The aim of this paper is to introduce a semantic methodology using ontology in order to improve results of data mining in judicial decisions database. An intelligent and automatic method to search for sentences in lawsuits related to the one in trial is presented. A judicial ontology is built with and without rules from experts. The method can provide judiciary celerity, seeking to solve the yearning...
This work presents images encoding and decoding using the theory of conformal mapping. The conformal mapping theory made changes in the domain of problems without modifying physical characteristics between the domains. Images were utilized and are transported between domains using transformation functions like encrypt keys. Developed method showed to be able to preserve original images characteristics...
Synchronous machines exhibit, under normal operating conditions, torque oscillation problems. This work presents a study that proposes a methodology for the reduction of these oscillations. It was tested in a synchronous generator powered environment with DC voltage supplying power to a common bus in permanent regime, this bus has the presence of a nonlinear load. There are oscillating components...
In this work, it is proposed, through mathematical and computational modeling, to simulate the electrical interactions between a synchronous generator of protruding poles with its field winding being fed by a DC component to a common bus in the permanent regime, subject to a nonlinear loads. Next, sine-wave voltage components with multiple frequencies of the fundamental are inserted in order to promote...
One of the most discussed schedule in Brazil is Education, and with it comes a lot of problems to solve. This project use of artificial intelligence, but precisely in the area of Machine Learning, to enable a solution, in relation to student monitoring. The research has done with students of technical high school education at the Federal Institute of Gois — Brazil, to find a method which would be...
This paper presents a comparison between the performances of LBP and Haar features in a Cascade Classifier, which aims automatically to count immature whiteflies (nymphs). The relevance of counting these nymphs is related to pest management, which leads to an increase in food production. Evaluate differences in weak classifiers can lead to better understanding and implementation of object detection...
The objective of this work is to analyze and understand the operation of the elevators system, simulating and optimizing the traffic of individuals in elevators. Passive elements (queues) and active (processors/servers) are analyzed. A simulation methodology is developed for passive and active elements using the system methodology to discrete events. The heuristic method is used in an attempt to find...
This paper presents an approach of investment risk analysis for small hydro power plants (SHPPs) considering energy trade in the short-term market in Brazil. The Monte Carlo Method, associated with a Cholesky decomposition, is applied to stochastic models to generate synthetic time series for water inflow and short-term electricity price. An economic approach is presented taking into account taxation...
This paper presents a method of the adequacy of voltage transgression in a real power distribution network. This method aims to adjust the voltage levels through the optimization of the insertion position of Photovoltaic (PV) Distributed Generation (DG) in the network. The real feeder was simulated using Open Distribution System Simulator (OpenDSS) software. The optimization used a deterministic method...
This paper presents the computer simulation of a switched reluctance machine (SRM) operating as a generator proposing an alternative for the representation of the inductances of the machine coils and their respective rates of variation. The simulation results show the reliability of the proposed model, especially in comparison with other models of machine inductance representation. The validation...
This paper presents an improvement of the optimization methodology of luminaire built by high power light emitting diode (LED) matrix. Six parameters that modify the geometry and layout of the luminaire are evaluated through a parameter sensitivity study. The result indicates that five parameters have an equally distributed sensitivity index, while one parameter presents an index with less than 1%...
The presence of gaps in time series makes the data analysis process difficult. Although there are several methods for filling such gaps, they do not present satisfactory results as the gap widens. The proposal of this paper is to present a new methodology that uses techniques of extraction of characteristics and identification of systems to fill the missing data. The proposed methodology was applied...
This paper presents study about Nonlinear Predictive Control, with a practical approach, applied to the speed control of the model's system, that is composed by a direct current (DC) machine, triggered by fully controlled three-phase AC-DC converter. The presence of the rectifier adds nonlinearity to the system in question. The practicality of the controller is related to its form of implementation,...
The purpose of this work is to present a new methodology to be applied in precision agriculture. In order to replace traditional methods, that are expensive, affect the environment and must be improved, it is presented the equipment and process of phytosanitary management using acoustic vibration in order to obtain correct application of product. The methodology is presented, in two case study: i)...
This article presents a way to solve Resource-Constrained Project Scheduling Problem with genetic algorithm and demonstrates the high relevance of metaheuristics for solution this type problem. Also shows various benchmarks with others heuristics. The benchmark performed compares directly to a relatively new heuristic and to several other works performed. The genetic algorithm together with the approach...
This paper proposes a development's prediction model based on Artificial Neural Network. The methodology proposed consists in: i) countries selection; ii) selection and obtainment of indicators referring to the selected countries; iii) proposal prediction model; iv) Artificial Neural Network training and validation. The results indicated predicted values close to the real values of the Brazilian indicators...
This paper presents comparative study between Fuzzy and Predictive controllers. They are implemented to speed control of a direct current (DC) machine, triggered by fully controlled three-phase AC-DC converter. Searching for high performance controllers, it's performed controllers' parameters optimization, through the use of the heuristic method Genetic Algorithm. It seeks to determine which of the...
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