120 documents found, page 1 of 12
Multi-objective optimization of a 2D backward-facing step channel with porous b...
Cavaleiro Costa, Sérgio; Janeiro, Fernando M.; Malico, IsabelPorous baffles can be used to enhance heat transfer in various engineering applications, including electronic cooling, gas turbine blades, and chemical reactors. Also, the backward-facing step is a widely used configuration in fluid dynamics studies due to its simplicity and relevance to real-world geometries. This study examines heat transfer and flow characteristics in a backward-facing step channel featuring...
Flexible Monte Carlo method for sensor calibration
Ramos, Pedro M.; Rodrigues, Nuno M.; Janeiro, Fernando M.Sensor/system calibration is a crucial step in every measurement system. To perform the calibration the system/sensor input is changed, and its output is measured. The device calibration is obtained from the measured input and output values. When the input/output relation is a straight line, a linear regression is the most common method to obtain the relation. However, this method does not consider uncertaintie...
Sinewave frequency estimation based on fractional Interpolated Discrete Fourier...
Janeiro, Fernando M.; Ramos, Pedro M.Frequency estimation is crucial in numerous scientific applications and have led to the development of various algorithms. Most approaches use the Discrete Fourier Transform followed by spectral interpolation. However, limitations arise when sinewave frequencies align closely with DFT lines especially for low Signal-to-Noise Ratios. Recent advances have employed non-integer Goertzel filters to compute Discrete ...
Measurement of Battery Aging Using Impedance Spectroscopy with an Embedded Mult...
Lourenço, J.; Rosado, Luis S.; Ramos, Pedro M.; Janeiro, Fernando M.This work describes the development of an embedded standalone measurement system that monitors the aging of batteries using impedance spectroscopy. The system generates a multisine stimulus that contains the frequency components at which the battery impedance is measured. Coherent generation and sampling is assured, and Goertzel filters, one for each measurement frequency, are updated with each new sample. This...
Design and Implementation of a Wireless Sensor Network for Water Resource Manag...
Luz, V. S.; Faria, P.; Rosado, L. S.; Janeiro, Fernando M.; Ramos, P. M.; Angelis, A. D.; Moschitta, A.; Carbone, P.; Meniconi, S.; Capponi, C.Water resource management is a crucial aspect to achieve efficient usage of resources and sustainable development. This paper presents research activities within the More4Water project, which aims to address the issues faced in the water resource management field by developing dedicated sensor networks and investigating novel modeling approaches. In particular, this paper focuses on the description of the early...
Artificial Intelligence for Fault Detection in Photovoltaic Panels
José, D.F.; Janeiro, Fernando M.; Pires, V.F.; Pires, A.J.; Martins, J.F.This paper presents an Artificial Intelligence solution for fault detection and classification in photovoltaic systems. The proposed tool integrates electrical and visual analysis methods, including I-V curve analysis, direct difference measurement, infrared thermography, electroluminescence imaging, and visual inspection. These methods are enhanced by deep learning models, which achieve high accuracy in identi...
Power Quality Transient Detection and Characterization Using Deep Learning Tech...
Rodrigues, Nuno M.; Janeiro, Fernando M.; Ramos, Pedro M.Power quality issues can affect the performance of devices powered by the grid and can, in severe cases, permanently damage connected devices. Events that affect power quality include sags, swells, waveform distortions and transients. Transients are one of the most common power quality disturbances and are caused by lightning strikes or switching activities among power-grid-connected systems and devices. Transi...
Deep Learning for Power Quality Event Detection and Classification Based on Mea...
Rodrigues, Nuno M.; Janeiro, Fernando M.; Ramos, Pedro M.Energy consumption has increased over the years, and, due to the dependency on fossil energy, alternative and renewable energy sources have been integrated to address environmental concerns. However, it is important to maintain the efficiency, reliability, and safety of the power grid amid the integration of different energy sources. IEEE and IEC standards regulate power quality (PQ) and define thresholds for P...
Battery Impedance Spectroscopy Embedded Measurement System
Cicioni, Gabriel; De Angelis, Alessio; Janeiro, Fernando M.; Ramos, Pedro M.; Carbone, PaoloThe evolution of rechargeable battery characteristics have led to their use in almost every device in our everyday life. This importance has also increased the relevance of estimating the remaining battery charge (state of charge, SOC) and their health (state of health, SOH). One of the methods for the estimation of these parameters is based on the impedance spectroscopy obtained from the battery output impedan...
AN OPTIMIZED APPROACH FOR PHOTOVOLTAIC PARAMETERS EXTRACTION
Mesbahi, Oumaima; Tlemçani, Mouhaydine; Janeiro, Fernando M.The state of deterioration of a photovoltaic technology's internal components, is the primary negative event that these technologies encounter [1]. The internal parameters of solar panels as well as the overall production might be affected by this degradation. The optimization procedure for obtaining these parameters goes through three phases; measuring the solar cell's response (current and voltage); calculati...