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Publications

2023

NonInvasive Glucose Fiber Sensor Based on Self-Imaging Technique: Proof of Concept

Authors
Cunha, C; Silva, S; Frazão, O; Novais, S;

Publication
EPJ Web of Conferences

Abstract
This paper proposes a proof of concept for a reflective fiber optic sensor based on multimode interference, designed to measure glucose concentrations in aqueous solutions that mimic the range of glucose concentrations found in human saliva. The sensor is fabricated by splicing a short section of coreless silica fiber into a standard single-mode fiber. By studying the principles of multimode interference and Self-imaging it was developed a sensing head that has a total length of 29.1 mm, approximately equal to the second self-image cycle. This sensing head allowed us to detect low concentrations of glucose (ranging from 0 to 268 mg/dl).

2023

Evaluation of Regularization Techniques for Transformers-Based Models

Authors
Oliveira, HS; Ribeiro, PP; Oliveira, HP;

Publication
IbPRIA

Abstract
In recent years the great success of transformers-based models initially employed in Natural Language (NLP) tasks has led to the development of several transformers variations to be employed in a wide range of domains, such as vision. With the correct amount of training data and proper training, transformers can perform excellently compared to the Convolution Neural Networks (CNN) counterpart in the vision tasks. However, the main drawback of transformers concerns the know memory requirements that often exceed the available training platform, growing in a quadratic form regarding the input image size, and a great tendency to overfit. Several works address the memory problem by relaxing the model architecture versions, but mainly with reduced prediction capabilities. In this work, we evaluate Random Patch erasing among the image patch level of the transformer model as a regularization technique to reduce overfitting while at the same time alleviating training time. The evaluated regularization technique achieves competitive results on several image classification medical datasets. The evaluated Visual Transformers (ViT) models allow to be trained in a single GPU, reaching similar results to CNN counterparts, obtaining an accuracy 91.2%, 79.2% in two competitive image datasets, and reducing the training time on average by 22% on the transformers models.

2023

Industry and innovation in the Alto Minho region: assessing regional performance

Authors
Abreu, M; Rodrigues, HS; Silva, Â; Garcia, JE;

Publication
Engineering Management in Production and Services

Abstract
Abstract As a tool, the Sustainable Development Goals (SDG) guide local and regional leaders in developing policy approaches for better social development. SDGs are 17 ambitious objectives towards a greener, healthier, more peaceful and equal planet, promoted by the United Nations to achieve by 2030. Having this performance in mind, countries and regions can measure their level of SDG implementation and rethink how they could promote prosperity, cooperation among regions and progress. This study focuses on SDG-9: Industry, innovation and infrastructure in ten municipalities of the Alto Minho region, Portugal. The main idea is to assess the level of each municipality in the achievement of the indicators related to this SDG. The similarities and differences between the municipalities can underline areas for joint efforts or investments in the development policy. This paper selected a performance analysis as a tool for informing on the amount of effort required to achieve SDG-9 at a local level, i.e., the Alto Minho region in the north of Portugal. If the trend of evolution is maintained, only Viana do Castelo will reach the full range of indicators for SDG-9, and Caminha will have 50 % of the indicators achieved. The remaining municipalities will reach at least half of the indicators, thus achieving a value lower than half of the target value. This approach could be replicated in other SDGs and other regions. This assessment allows the region’s stakeholders to indicate areas of required action to achieve the SDG.

2023

Deep Learning Glaucoma Detection Models in Retinal Images Capture by Mobile Devices

Authors
Rezende, RF; Coelho, A; Fernandes, R; Camara, J; Neto, A; Cunha, A;

Publication
Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST

Abstract
Glaucoma is a disease that arises from increased intraocular pressure and leads to irreversible partial or total loss of vision. Due to the lack of symptoms, this disease often progresses to more advanced stages, not being detected in the early phase. The screening of glaucoma can be made through visualization of the retina, through retinal images captured by medical equipment or mobile devices with an attached lens to the camera. Deep learning can enhance and increase mass glaucoma screening. In this study, domain transfer learning technique is important to better weight initialization and for understanding features more related to the problem. For this, classic convolutional neural networks, such as ResNet50 will be compared with Vision Transformers, in high and low-resolution images. The high-resolution retinal image will be used to pre-trained the network and use that knowledge for detecting glaucoma in retinal images captured by mobile devices. The ResNet50 model reached the highest values of AUC in the high-resolution dataset, being the more consistent model in all the experiments. However, the Vision Transformer proved to be a promising technique, especially in low-resolution retinal images. © 2023, ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.

2023

Geovisualisation Tools for Reporting and Monitoring Transthyretin-Associated Familial Amyloid Polyneuropathy Disease

Authors
Lôpo, RX; Jorge, AM; Pedroto, M;

Publication
MACHINE LEARNING AND PRINCIPLES AND PRACTICE OF KNOWLEDGE DISCOVERY IN DATABASES, ECML PKDD 2022, PT I

Abstract
Transthyretin-associated Familial Amyloid Polyneuropathy (TTR-FAP) is a chronic fatal disease with a high incidence in Portugal. It is therefore relevant to provide professionals and citizens with a tool that enables a detailed geographical and territorial study. For this reason, we have developed an web based application that brings together techniques applied to spatial data that allow the study of the historical progression and growth of cases in patients' residential areas and areas of origin as well as an epidemic forecast. The tool enables the exploration of geographical longitudinal data at national, district and county levels. High density regions and periods can be visually identified according to parameters selected by the user. The visual evaluation of the data and its comparison across different time spans of the disease era can have an impact on more informed decision making by those working with patients to improve their quality of life, treatment or follow-up. The tool is available online for data exploration and its code is available on GitHub for adaptation to other geospatial scenarios.

2023

SUSTAINABLE SOCIAL HOUSING THE RIO DE JANEIRO CASE STUDY

Authors
Jorio, M; Amaral, A; Neto, T; Ferreira, P;

Publication
PROCEEDINGS OF THE 5TH INTERNATIONAL CONFERENCE ON PRODUCTION ECONOMICS AND PROJECT EVALUATION, ICOPEV 2022

Abstract
The urban development model used in the past has proved unsustainable. Due to this fact, cities such as Rio de Janeiro, with high population density, mainly regarding precarious settlements, need immediate practical actions to become more sustainable. The insufficiency of planning and investments contributed to the city occupying the 8th position of the most vulnerable cities in the world, triggering the primary motivation of this research study. Therefore, the leading research focused on exploring how sustainable social housing (SH) could contribute to Rio de Janeiro becoming more sustainable. Literature review, document analysis and semi-structured interviews were carried out to identify sustainable SH in Rio de Janeiro that can serve as a benchmark and listen to the opinion of engineers or architects regarding the importance of sustainable SH for the population and the city. Thus, in consonant with structural changes in thinking, production, and living, it was possible to identify the main contributions of sustainable SH to the city.

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