José Farinha

Prof. José Farinha

DEM, Coimbra Institute of Engineering, Polytechnic Institute of Coimbra, Coimbra, Portugal
orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 October 2021 in Energies
Verified
Journal Article
Open access
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Balduino César MateusBalduino César Mateus
Balduino César Mateus
mateus mendesmateus mendes
mateus mendes
José FarinhaJosé Farinha
José Farinha
RARui Assis
Rui Assis
Antonio J. Marques CardosoAntonio J. Marques Cardoso
Antonio J. Marques Cardoso
The accuracy of a predictive system is critical for predictive maintenance and to support the right decisions at the right times. Statistical models, such as ARIMA and SARIMA, are unable to describe the stochastic nature of the data. Neural networks, such as long short-term memory (LSTM) and the gated recurrent unit (GRU), are good predictors for univariate and multivariate data. The present paper describes a case study where the performances of long short-term memory and gated recurrent units are compared, based on different hyperparameters. In general, gated recurrent units exhibit better performance, based on a case study on pulp paper presses. The final result demonstrates that, to maximize the equipment availability, gated recurrent units, as demonstrated in the paper, are the best options.

22 May 2021 in Applied Sciences
Verified
Journal Article
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AMAna Rita Malta
Ana Rita Malta
mateus mendesmateus mendes
mateus mendes
José FarinhaJosé Farinha
José Farinha
Maintenance professionals and other technical staff regularly need to learn to identify new parts in car engines and other equipment. The present work proposes a model of a task assistant based on a deep learning neural network. A YOLOv5 network is used for recognizing some of the constituent parts of an automobile. A dataset of car engine images was created and eight car parts were marked in the images. Then, the neural network was trained to detect each part. The results show that YOLOv5s is able to successfully detect the parts in real time video streams, with high accuracy, thus being useful as an aid to train professionals learning to deal with new equipment using augmented reality. The architecture of an object recognition system using augmented reality glasses is also designed.

16 February 2019 in Actuators
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HRHugo Raposo
Hugo Raposo
José FarinhaJosé Farinha
José Farinha
IFInácio Fonseca
Inácio Fonseca
LFLuis Ferreira
Luis Ferreira
This paper presents a case study and a model to predict maintenance interventions based on condition monitoring of diesel engine oil in urban buses by accompanying the evolution of its degradation. Many times, under normal functioning conditions, the properties of the lubricants, based on the intervals that manufacturers recommend for its change, are within normal and safety conditions. Then, if the lubricants’ oil condition is adequately accompanied, until reaching the degradation limits, the intervals of oil replacement can be enlarged, meaning that the buses’ availability increases, as well as their corresponding production time. Based on this assumption, a mathematical model to follow and to manage the oil condition is presented, in order to predict the next intervention with the maximum time between them, which means the maximum availability.

9 September 2020 in Energies
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Journal Article
Open access
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DMDiogo Menezes
Diogo Menezes
mateus mendesmateus mendes
mateus mendes
JAJorge Alexandre Almeida
Jorge Alexandre Almeida
José FarinhaJosé Farinha
José Farinha
The use of clean and renewable energy sources is increasingly important, for economic and environmental reasons. Wind plays a key role among renewable energy sources. Hence, the location, monitoring and maintenance of wind turbines are areas that have received more and more attention in recent years. The paper presents a survey of datasets of wind resources, wind farm installed capacity and wind farm operation, which contain generous amounts of data. Those datasets are important tools, freely available for analysis of wind resources and study of the performance of wind turbines. A short analysis of one of the datasets is also presented, identifying different operational regions, and the ones more likely to aggregate failures. Principal Component Analysis (PCA) is used to study wind turbines’ behavior.

1 January 2021 in Applied Soft Computing
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Journal Article
Closed access
Hamzeh SoltanaliHamzeh Soltanali
Hamzeh Soltanali
Abbas RohaniAbbas Rohani
Abbas Rohani
MFMohammad Hossein Abbaspour Fard
Mohammad Hossein Abbaspour Fard
José FarinhaJosé Farinha
José Farinha

1 July 2019 in Tribology International
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Journal Article
Closed access
HRHugo Raposo
Hugo Raposo
José FarinhaJosé Farinha
José Farinha
Inácio FonsecaInácio Fonseca
Inácio Fonseca
DGDiego Galar
Diego Galar