University of Coimbra

Consultancy : Research : Academic

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Coimbra, Portugal

The University of Coimbra is a public research university in Coimbra, Portugal. First established in Lisbon in 1290, it went through a number of relocations until moving permanently to Coimbra in 1537.

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Improved GRU prediction of paper pulp press variables using different pre-processing methods

📅 Date:

✍️ Authors: Balduíno César Mateus, Mateus Mendes, José Torres Farinha, António Marques Cardoso, Rui Assis, Hamzeh Soltanali

🔖 Topics: Gated Recurrent Unit, Predictive Maintenance

🏭 Vertical: Pulp and Paper

🏢 Organizations: Lusófona University, University of Beira Interior, University of Coimbra


Predictive maintenance strategies are becoming increasingly more important with the increased needs for automation and digitalization within pulp and paper manufacturing sector.Hence, this study contributes to examine the most efficient pre-processing approaches for predicting sensory data trends based on Gated Recurrent Unit (GRU) neural networks. To validate the model, the data from two paper pulp presses with several pre-processing methods are utilized for predicting the units’ conditions. The results of validation criteria show that pre-processing data using a LOWESS in combination with the Elimination of discrepant data filter achieves more stable results, the prediction error decreases, and the predicted values are easier to interpret. The model can anticipate future values with MAPE, RMSE and MAE of 1.2, 0.27 and 0.30 respectively. The errors are below the significance level. Moreover, it is identified that the best hyperparameters found for each paper pulp press must be different.

Read more at Production & Manufacturing Research

Researchers Consider the Circular Economy in Pulp and Paper Industries

📅 Date:

✍️ Author: Reginald Davey

🔖 Topics: Sustainability

🏭 Vertical: Pulp and Paper

🏢 Organizations: University of Aveiro, University of Coimbra


The paper and pulp industries can benefit greatly from a cyclical model of manufacture. These industries are responsible for the consumption of most of the lignocellulosic biomass produced in the world. In 2020, the European paper and pulp industries alone consumed an estimated 146.5 million cubic meters of wood. The transition to a green economy approach is a chief concern in these industries.

Read more at AZO Materials