CTM - Comunicações em actas de encontros científicos internacionais
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- Geomatemática Aplicada ao Estudo de Contaminações decorrentes de Áreas Mineiras Abandonadas. O caso de estudo da Mina de Vale das Gatas (Portugal)Publication . Fagundes, Isabel; Góis, Joaquim; Fonseca, Barbara; Rodrigues, José Feliciano; Carvalho, Cristina Isabel Paulo; Bravo, PauloRESUMO: O objetivo deste trabalho é a aplicação de uma série de modelos geomatemáticos que analisem, não só o sistema de relações entre os diferentes Elementos Potencialmente Tóxicos (EPT), mas também as suas dispersões espaciais nas áreas circunvizinhas a antigas explorações mineiras abandonadas. O recurso a técnicas da estatística multivariada no âmbito dos Métodos Fatoriais (Análise em Componentes Principais e Análise de Correspondências), aliada a modelos geoestatísticos caracterizadores do comportamento espacial dos EPT, permitem não só efetuar um diagnóstico ambiental do local, mas também equacionar uma eventual viabilidade económica para o reaproveitamento (remineração e revalorização) das escombreiras de antigas explorações mineiras abandonadas.
- Ecogeodidactic resource - A circular path for natural stone wastes: Didactic interest, economic potential and safety assessment proposalPublication . Torres, Maria Madalena; Alves, Raquel; Carvalho, Cristina Isabel Paulo; Figueiredo, Bruno; Vilaça, Maria TeresaABSTRACT: This research project integrates Sustainable Development Goals (SDGs), specifically Quality Education (SDG4) and Responsible Consumption and Production (SDG12), and involves Education Sciences, Geosciences, and (Eco)Design. The project aims to create an ecogeodidactic resource that includes both physical and theoretical components, pedagogical strategies, and teacher training, while incorporating inputs from children and the educational community. The methodologies of action-research and cocreation have been adopted, focusing specifically on Environmental Education for Sustainability within the Geosciences (mineral resources and geological heritage). The project seeks to revalue stone waste from slab processing, by developing a high-value by-product. During the pilot phase, stone pieces (“geoelements”) were selected for interaction with preschool children, and a prototype was created to be installed in a kindergarten to monitor its impact. This resulted in a validation framework, that allowed for the discussion of the geodidactic interest, and the economic potential of this Project, as well as the definition of the initial guidelines for assessing their safety.
- Natural Stone Image Classification Using Online Databases and Convolutional Neural NetworksPublication . Brito, J. H.; Morim, D. M.; Carvalho, Cristina Isabel Paulo; Alves, RaquelABSTRACT: In this paper, we discuss the relevance of two distinct types of online natural stone databases (technical-institutional repositories and logistics-commercial e-platforms) for extracting (training and testing) input images and creating an automatic visual inspection system for natural stone classification. Using convolutional neural networks (CNNs) and images from a selected online data repository, a Deep Learning (DL) system was developed to estimate the class of the natural stone in a given image. The DL models were developed through transfer learning from existing image classifiers, as pre-trained classifiers were retrained on our dataset. Our best model achieved an Accuracy of 70.3% and an F-score of 0.67 for 70 classes.
- Natural Stones from EU - Denomination Criteria Standard: A ReviewPublication . Alves, Raquel; Carvalho, Cristina Isabel Paulo; Carvalho, Jorge; Silva, António José Ferreira da; Magalhães, Anabela; Rebola, Paula; Matias, Gina; Vinagre, Ana; Galego Lopes, Joaquim LuísABSTRACT: Harmonization is vital in the European Union. It is mainly applied to materials, processes, products and services. However, it is also crucial for other domains. An example of this is the denomination of natural stones. It is important that denomination meets strict criteria to promote natural stone Market, as well as their products in the imperative new “Construction Products Regulation (CPR)”. This was the purpose behind the development and recent revision of EN 12440. However, the important role that was intended for this standard in the natural stone sector was never fully achieved, due to the vague and unobjective way in which the denomination criteria were laid down. This review aims to analyse the standard, pointing out what needs to be harmonized, and to present concrete proposals for its improvement, so that the standard can fully perform its purpose.
- Natural Stones from Portugal : Proposal for harmonizing Commercial NamesPublication . Carvalho, Jorge; Carvalho, Cristina Isabel Paulo; Lopes, Luis; Silva, António; Santos, Catarina; Sousa, Luís; Martins, Ruben; Marques, CéliaABSTRACT: Over the years, the Portuguese Geological Survey – LNEG, has been dedicated to the characterization of Portuguese natural stones. Today, a newly updated LNEG web portal contains information on 149 natural stones, which are known by their unique trade names. Many of these names integrate the EN 12440 - Natural Stone - Denomination Criteria standard, but others do not. Furthermore, there many other names used to identify natural stones that are traded today and that do not integrate the LNEG web Portal or the EN 12440. This work presents a harmonization proposal for the commercial denomination of the Portuguese natural stones. It is a working basis for a final list that must be submitted to ISO/Technical Committee 118 – Natural Stones.
- House dusts of a volcanic island: potential impacts on human healthPublication . Candeias, Carla; Ávila, Paula Freire; Cunha, Leandro; Sequeira, Cristina; Rocha, FernandoABSTRACT: Fogo island (Cape Verde), has an active volcano that last erupted in 2014-15, with melts mainly alkaline, of basanitic to tephritic composition. Dwellings dust composition is the result of natural and anthropogenic interactions. Nineteen house dusts were collected, in representative dwellings all over the island. Fractions < 2 mm was analyzed by ICP-MS, XRF and XRD and SEM for chemical, mineralogical, and morphological characterization. Mineral phases revealed several minerals linked to the volcanic origin. Iron mean concentration in soils, is above the 2014-105 eruption lava mean. Potentially toxic elements were below Acceptable Values (AV), e.g., As 0.6 to 3.3 mg/kg, except once sample 111 mg/kg (AV = 20 mg/kg); Cd, 0,5-3.6 mg/kg (AV = 3 mg/kg). Elements Ni and V presented concentrations above AV in all samples. But is Ti with concentrations much above AV. Risk assessment (USEPA) found As and Ni over the car cinogenic target Risk in most samples, while systemic toxicity in children is mostly due to Fe, V and Zr concentrations. Higher particles concentration is > 50 µm in diameter, suggesting that bioaccessible fraction might not be high, thus, reducing risk.
- "Schistose" rocks as a resourcePublication . Noronha, Fernando; Sousa, Mónica; Carvalho, Cristina Isabel Paulo; Moura, A. Casal; Ramos, João Farinha
- Natural stone from the Azores archipelago : relationship between lithology and physical-mechanical behaviourPublication . Silva, João B. P.; Carvalho, Cristina Isabel Paulo; Caetano, Sérgio Diogo; Gomes, Celso
- Stains in pavement applications of a portuguese limestonePublication . Simão, J.; Pires, Vera; Galhano, António Carlos; Carvalho, Cristina Isabel Paulo
- Trabalho isolado. Um fator subestimado na prevençãoPublication . Matos, Maria Luísa Ferreira; Santos, Paula; Barbosa, Fernando