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Assessing the sustainable performance of the transport sector in European countries using alternative benefit-of-the-doubt models
Full text linkThe energy policy of the European Union stresses the need for sustainable energy consumption, improvements
in energy efficiency and lower fossil fuel dependence in a decoupling strategy from unstable democracies.
Transportation still represents a sector largely dependent on fossil fuels, which come with several negative
impacts. Measuring and assessing the sustainability of the transport sector becomes necessary. This study aims
to assess the sustainability performance of the transport sector across 28 European countries over a four-year
period, aligned with the policy agenda outlined in strategic documents. The methodological approach involves
applying Benefit-of-the-Doubt (BoD) models, comparing a version that uses transformation methods for antiisotonic
sub-indicators with a variant that directly incorporates these sub-indicators as reverse indicators. In
general, the European countries have improved the sustainability performance of their transport sector during
the time span analyzed according to the results of both models. For the inefficient units, two improvement
strategies are presented based on the profiles identified on the benchmarks from both models, which can be
alternative stages to achieve the robust best practices of the benchmarks.This work was supported by the Foundation for Science and Tech-nology (FCT, Portugal), through the Research Centre in Digitalizationand Intelligent Robotics (CeDRI) [Grant numbers UIDB/05757/2020(DOI: 10.54499/UIDB/05757/2020) and UIDP/05757/2020 (DOI:10.54499/UIDP/05757/2020)], and the Associate Laboratory for Sus-tainability and Technology in Mountains Regions (SusTEC) [Grantnumber LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020)].
This project is funded by the European Union under Horizon Eu-rope (project 101078933 - STEP - STEM and Equality, Diversity andInclusion: an open dialogue for research enhancement in Portugal).info:eu-repo/semantics/publishedVersio
Can companies improve their performance through corporate social responsibility, with the mediating role of business model innovation and competitive advantage?
Full text linkThe present study intends to examine the impact of corporate social responsibility components as proposed by Carroll, together with environmental responsibility, on business model innovation, competitive advantage, and firm performance within the context of small and medium-sized enterprises. The results of this study were obtained through the examination of 483 questionnaires collected from small and medium-sized enterprises in Iran. The application of structural equation modelling was employed to assess the validity of the conceptual model. The findings of this study indicate that the various elements of corporate social responsibility (except for philanthropic and environmental aspects) have a direct and statistically significant impact on business model innovation. Furthermore, it is worth noting that business model innovation has a direct and substantial impact on competitive advantage. Moreover, the results of this study demonstrate a direct and substantial impact of competitive advantage on firm performance. This study represents one of the first investigations that particularly analyzes the influence of individual dimensions of corporate social responsibility on the process of business model creation, as far as our knowledge goes. This study incorporates a novel feature, namely environmental responsibility, into Carroll's existing model, in response to the growing significance of environmental concerns. The findings of this study provide managers with an enhanced understanding of corporate social responsibility and its impact on organizational performance. This study demonstrates to managers the significance of directing their attention towards specific dimensions of corporate social responsibility that can potentially business model innovation.info:eu-repo/semantics/publishedVersio
Selective biphasic oxidation of nitrogenated contaminants with H2O2 using polyolefin-derived carbon nanotubes
Full text linkLiquid/liquid biphasic oxidations are extensively employed in the chemical industry to manufacture a variety of
chemicals and for environmental issues, such as the oxidative denitrogenated (ODN) and desulfurization of fuels.
The ubiquitous presence of nitrogenated and sulfonated compounds in petroleum-derived fuels is associated with
environmental and health issues, driving legislation to become stricter regarding the content or related emissions
of those impurities. However, catalysts with high performance, low cost and high activity towards selective
oxidation of targeted contaminants should be developed. This work deals with the oxidative denitrogenation of
quinoline and pyridine, used as model nitrogenated compounds, using carbon nanotubes as catalysts, which were
derived from polyolefins (low-density polyethylene, high-density polyethylene and propylene) representative of
plastic solid waste (PSWs) mixtures found in municipal solid wastes. The carbon precursor used offers not only a
solution to reduce PSWs accumulation in waste management systems but also a cheap feedstock for preparing
CNTs. All PSWs-derived CNTs allowed to remove quinoline completely, pyridine, and both of them in a mixture
under the same conditions (1 h, 80 ◦C, ccat = 2.5 g L^-1, [H2O2]0 = 247 g L^-1, O/W volume ratio = 80:20, [N]0 =
108 mg L^-1). These results were maintained for up to 5 additional reuse cycles for the catalyst prepared with
mixed polyolefins.This work was financially supported by project "PLASTIC_TO_FUEL&
MAT – Upcycling Waste Plastics into Fuel and Carbon Nanomaterials"
(PTDC/EQU-EQU/31439/2017), CIMO (UIDB/00690/2020)
through FEDER under Program PT2020 and by national funds through
the FCT/MCTES (PIDDAC): LSRE-LCM, UIDB/50020/2020 (DOI:
10.54499/UIDP/50020/2020) and UIDP/50020/2020 (DOI: 10.54499/
UIDP/50020/2020); and ALiCE, LA/P/0045/2020 (DOI: 10.54499/LA/
P/0045/2020). Fernanda F. Roman acknowledges the national funding
by FCT and the European Social Fund, FSE, through the individual
research grant SFRH/BD/143224/2019. Adriano Santos Silva thanks the
financial support from FCT under MIT Portugal Program with Ph.D.
grant SFRH/BD/151346/2021. J. L. Diaz de Tuesta acknowledges the
research grant (2022-T1/AMB-23946) by the program of Atracción al
Talento of Comunidad de Madrid (Spain). The authors are grateful to
Sociedade Ponto Verde for the financial support through the project
“Estudo técnico-económico para a valorização de resíduos de embalagens
plásticas em nanotubos de carbono."info:eu-repo/semantics/publishedVersio
Climate Denialism on Social Media: Qualitative Analysis of Comments on Portuguese Newspaper Facebook Pages
Full text linkClimate denialism represents a significant challenge to public awareness and the implementation of effective environmental policies. In Portugal, as in other countries, social networks have been the place where denialist ideas are disseminated, influencing the public perception of the climate crisis. This research aims to understand how denialist discourse manifests and spreads on digital platforms. The research question of this work is: how does climate denialist discourse manifest itself on social media in Portugal? This work has two objectives: (1) to analyze the arguments and discursive strategies used by climate deniers in comments on Facebook, specifically on the pages of the three largest Portuguese newspapers, and (2) to understand the social and discursive dynamics that underpin their beliefs. This work adopted a qualitative methodology that involved manual data collection during the month of September 2024. Posts about climate that were informative were selected. The comments were examined manually and categorized by type of discourse. This approach enabled capturing specific nuances and contexts of denial discourses, providing a deeper understanding of the phenomenon. The study concluded that (I) comments that use fallacies or rhetoric that deny the climate crisis tended to receive more “likes” and approval from users; (II) fallacies that do not offer scientific evidence to refute the existence of climate change were identified in all these comments.This work has been supported by FCT—Fundação para a Ciência e Tecnologia within the
Project Scope: UIDB/05777/2020.info:eu-repo/semantics/publishedVersio
The genetic composition of honey bee populations from the Azores
No full textDouble degree master's programme with Université Libre de TunisThis study was funded by Portuguese funds through FCT (Fundação para a Ciência e a Tecnologia) in the framework of the project BeeHappy grant number POCI-01-0145- FEDER-029871. FCT provided financial support by national funds (FCT/MCTES) to CIMO (UIDB/00690/2020)
Avaliação dos serviços ecossistêmicos e qualidade da arborização: Um estudo de caso no Instituto Politécnico de Bragança
Full text linkMestrado de dupla diplomação com a UTFPR, Universidade Tecnológica Federal do ParanáOs espaços verdes urbanos desempenham um papel fundamental na sustentabilidade dos
ecossistemas urbanos, fornecendo diversos serviços ecossistêmicos (SE). No entanto, a
quantificação e valoração dos benefícios ecológicos desses espaços ainda são pouco
abordadas e aplicadas no planeamento e design urbano. Face a este gargalo, este estudo
teve como objetivo quantificar os SE e atribuir seus respectivos valores monetários, além
de avaliar a diversidade das espécies identificadas no inventário arbóreo do Instituto
Politécnico de Bragança (IPB), no nordeste de Portugal. Foram utilizados os índices de
Shannon (H’), Simpson (D’) e a Equitabilidade de Pielou (J’), a fim de atribuir a
diversidade florística da área. A modelação dos SE, foi realizada por meio do software i-
Tree Eco v.6, concomitante aos dados do inventário (espécie; diâmetro altura do peito;
altura total; condição fitossanitária da copa; e uso do solo) e aos dados das condições
socioambientais locais (habitantes, habitantes por km², precipitação e poluição anual). O
inventário arbóreo do IPB contabilizou 517 árvores, distribuídas em 45 espécies. As
espécies Cupressus lusitanica , Aesculus x carnea e Platanus x hybrida representam
28,2% da população total. A diversidade, avaliada pelos índices de H’ (3,15), D’ (0,06) e
J’ (0,83), foi considerada moderada e bem distribuída, indicando baixa dominância e boa
uniformidade entre as espécies. Estima-se que as árvores removam 84,93 kg de poluentes
anualmente, gerando 36,43 euros, com Cupressus lusitanica e Platanus x hybrida
responsáveis por 82% dessa remoção. Embora emitam 42,9 kg/ano de compostos
orgânicos voláteis, o saldo líquido é positivo, com 42 kg de poluentes removidos por ano.
As árvores absorveram 3,51 ton/ano de CO₂, avaliado em 390 euros por ano, e estocam
79,8 ton, correspondendo a 8.860 euros. A população arbórea também evitou o
escoamento com 73,12 m³/ano de água, representando 678 euros. O valor total dos
serviços ecossistêmicos alcança 1.104 euros anuais, chegando aos 9.960 euros , quando
somados ao CO₂ estocado. Cupressus lusitanica foi a espécie que mais contribuiu
economicamente, gerando mais de 3.900 euros em benefícios. O software i-Tree Eco
mostrou-se eficaz na quantificação de SE em ambientes urbanos. Os resultados do
inventário arbóreo do IPB enfatizaram a importância dos espaços verdes na mitigação dos
impactos da urbanização, além de servirem como uma ferramenta consultiva para
aprimorar normas de controle e projetos de gestão, garantindo a sustentabilidade e a
resiliência urbana.Urban green spaces play a fundamental role in the sustainability of urban ecosystems,
providing various ecosystem services (ES). However, the quantification and valuation of
the ecological benefits of these spaces are still poorly addressed and applied in urban
planning and design. Given this bottleneck, this study aimed to quantify ES and assign
their respective monetary values, as well as assessing the diversity of the species
identified in the tree inventory of the Polytechnic Institute of Bragança (IPB), in
northeastern Portugal. The Shannon (H'), Simpson (D') and Pielou Equitability (J') indices
were used to assess the floristic diversity of the area. The SE modeling was carried out
using the i-Tree Eco v.6 software, in conjunction with the inventory data (species; breast
height diameter; total height; phytosanitary condition of the canopy; and land use) and
data on local socio-environmental conditions (inhabitants, inhabitants per km²,
precipitation and annual pollution). The IPB tree inventory counted 517 trees, distributed
among 45 species. The species Cupressus lusitanica, Aesculus x carnea and Platanus x
hybrida represent 28.2% of the total population. Diversity, assessed by the H' (3.15), D'
(0.06) and J' (0.83) indices, was considered moderate and well distributed, indicating low
dominance and good uniformity between species. It is estimated that trees remove 84.93
kg of pollutants annually, generating 36.43 euros, with Cupressus lusitanica and Platanus
x hybrida responsible for 82% of this removal. Although they emit 42.9 kg/year of volatile
organic compounds, the net balance is positive, with 42 kg of pollutants removed per
year. The trees absorbed 3.51 tons/year of CO₂, valued at 390 euros per year, and stored
79.8 tons, corresponding to 8,860 euros. The tree population also prevented runoff with
73.12 m³/year of water, representing 678 euros. The total value of ecosystem services
amounts to 1,104 euros per year, reaching 9,960 euros when added to the CO₂ stored.
Cupressus lusitanica was the species that contributed most economically, generating
more than 3,900 euros in benefits. The i-Tree Eco software proved to be effective in
quantifying ES in urban environments. The results of the IPB tree inventory emphasized
the importance of green spaces in mitigating the impacts of urbanization, as well as
serving as a consultative tool for improving control standards and management projects,
guaranteeing sustainability and urban resilience
Desenvolvimento de robô móvel de baixo custo para desenho
Full text linkEsta dissertação reflete a realização de um projeto no âmbito da robótica, através do desenvolvimento de um robô móvel autónomo com a capacidade de desenhar uma imagem monocromática pré-definida. Esta é a matriz fulcral para o qual o projeto foi concebido. Durante o decorrer da dissertação, existe uma distinção na robótica móvel no qual o projeto se encontra inserido e a sua condição dentro desta. É introduzido uma integração do impacto da tecnologia, neste caso, na robótica aliada à inteligência artificial. São também abordadas as áreas que proliferam a adjacência envolvente do mesmo, como as áreas STEAM e descreve-se o campo da robótica móvel, onde se apresentam exemplos de diversos tipos de robôs e conceções robóticas existentes. Dentro desta gama, exploram-se os seus detalhes. São descritas com detalhe as componentes integrantes do sistema criado como produto deste projeto, nomeadamente as suas três grandes componentes, como a eletrónica, a mecânica e a programação. Nestas, é descrito a eventual escolha e as bases de decisões das mesmas, bem como o percurso delineado. Sendo apresentado o protótipo final e o seu desempenho com demonstração de resultados e uma possível aprimoração. Este é um projeto que na sua implementação envolve uma vertente multidisciplinar nas necessidades práticas de execução e concretização do mesmo. Uma característica que poderá ser observada no decorrer do mesmo.This dissertation reflects the realisation of a project in the field of robotics, through the development of an autonomous mobile robot with the ability to draw a predefined monochrome image. This is the core matrix for which the project was conceived. Throughout the dissertation, a distinction is made between the mobile robotics in which the project is inserted and its status within it. An integration of the impact of technology, in this case robotics combined with artificial intelligence, is introduced. The areas that proliferate around it are also addressed, such as STEAM areas, and the field of mobile robotics is described, where examples of different types of robots and existing robotic designs are presented. Within this range, their details are explored. The integral components of the system created as a product of this project are described
in detail, namely its three main components, such as electronic, mechanic and program- ming. The eventual choice of components and the basis for their decisions are described, as well as the path outlined. The final prototype and its performance are presented, with a demonstration of the results and possible improvements. This is a project that, in its implementation, involves a multidisciplinary approach to the practical needs of its execution and realisation. This is a characteristic that can be observed during the course of the project
Uso de tecnossolos na recuperação de áreas geridas com fogo controlado na montanha mediterrânea: efeitos em propriedades físicas e químicas do solo
Full text linkMestrado de dupla diplomação com a UTFPR, Universidade Tecnológica Federal do ParanáO solo é um recurso essencial para a vida, mas enfrenta degradação crescente
devido ao seu uso antrópico inadequado e aos incêndios florestais frequentes na Europa
Mediterrânea. A aplicação de Tecnossolos, que são solos modificados ou artificialmente
criados, surge como uma solução para a recuperação de áreas degradadas, permitindo
restaurar as funções ecológicas e produtivas dos solos.
Neste estudo, procedeu-se à aplicação de Tecnossolos na superfície do solo, como
solução inovadora para a recuperação de áreas ardidas por fogo controlado no Parque
Natural de Montesinho, NE Portugal. Estudaram-se os efeitos da aplicação do
Tecnossolo, para um período de 27 meses, em propriedades físicas (permeabilidade,
densidade, capacidade de campo, capacidade máxima para a água, estabilidade dos
agregados) e químicas do solo (matéria orgânica, azoto, fósforo e potássio extraíveis, pH).
Para esse efeito, foram estabelecidas duas áreas de amostragem, com e sem aplicação de
Tecnossolo. Em cada área de amostragem definiu-se um transeto e em cada transeto
selecionaram-se quatro pontos onde ocorreu à coleta de amostras de solo nas
profundidades 0-3, 3-6, 6-10 e 10-20 cm. Também foram coletadas amostras de
Tecnossolo (espessura média de 5 cm).
Os resultados indicam que a aplicação do Tecnossolo melhorou significativamente
algumas propriedades físicas e químicas do solo, favorecendo a retenção de água e a
redução da acidez do solo. O teor de matéria orgânica não sofreu alterações significativas
e os níveis de fósforo e potássio extraíveis foram maiores nas áreas tratadas com
Tecnossolo, o que contribuiu para uma maior fertilidade e capacidade de suporte das
plantas. Observou-se também uma melhora na estrutura do solo, com diminuição da
densidade aparente e aumento da porosidade, permitindo melhor infiltração de água e
aeração. De maneira geral, a aplicação do Tecnossolo se mostrou eficaz na recuperação
dos impactos produzidos pelo fogo no solo.Soil is an essential resource for life, but it faces degradation due to its inappropriate
anthropogenic use and frequent forest fires in Mediterranean Europe. The application of
Technosols, which are either modified or artificially created soils, appears as a solution
for the recovery of degraded areas, allowing the ecological and productive functions of
soils.
In this study, Technosols were applied to the soil surface as an innovative solution
for the recovery of burned areas by controlled fire in the Montesinho Natural Park, NE
Portugal. The effects of applying the Technosols over a period of 27 months on the soil's
physical (permeability, density, field capacity, maximum water capacity, aggregate
stability) and chemical (organic matter, nitrogen, extractable phosphorus, and potassium,
pH) properties were studied. For this purpose, two sampling areas were established, with
and without the application of Technosols. One transects was defined in each sampling
area, and four points were selected in each transect where soil samples were taken at
depths of 0-3, 3-6, 6-10, and 10-20 cm. Samples of Technosols were also collected and
applied to the surface (average thickness of 5 cm).
The results indicate that the application of Technosols significantly improved some
of the soil's physical and chemical properties, favoring water retention and reducing soil
acidity. The organic matter content and levels of extractable phosphorus and potassium
were higher in the areas treated with Technosols, which contributed to greater fertility
and plant support capacity. There was also an improvement in soil structure, with a
reduction in bulk density and an increase in porosity, allowing for better water infiltration
and aeration. Overall, the application of Technosols proved to be effective in recovering
from the impacts of fire on the soil
Regeneração do rural através do turismo criativo: Discursos locais sobre o património cultural
Full text linkAlternative forms of tourism are gradually emerging, as tourism transforms itself and adopts new forms of consumption and development. It is therefore necessary to understand the new approaches to tourism sustainability in order to achieve more transformative results for destinations and their local communities. This research aims to identify creative tourism as the most equitable approach to achieving the sustainability and the regeneration of rural territories. Thus, the general objective is to understand how Cultural Heritage, as a tourist resource, can be used to promote regenerative impacts in a rural region of Portugal, particularly in Trás-os-Montes. As part of a qualitative methodology, the focus group interview technique was applied to three of the destination's stakeholders: Municipalities; Tourism agents; and Residents, to discuss the tourism promotion of a very particular heritage and its implications. The main results identify the greatest consensus among the participants, essentially regarding the suitability of creative tourism for the Cultural Heritage under study, from different perspectives. As well as five potential regenerative benefits for the destination: (i) Local Sourcing Practices, (ii) Social and Cultural Involvement, (iii) Sustainable Economic Performance, (iv) Inclusiveness Management, and (v) Education and Capacity Building, associated with nine United Nations Sustainable Development Goals (SDGs).info:eu-repo/semantics/publishedVersio
Avaliação experimental e numérica de uma prótese femoral
Full text linkA artroplastia total da anca (ATQ) é uma técnica cirúrgica bem-sucedida que pode ser utilizada para o tratamento eficaz de fraturas do colo do fémur, osteoartrite, tumores, necrose vascular, falha na fixação interna, displasia do desenvolvimento e artrite reumatoide. O grande número de operações de revisão realizadas todos os anos em resultado de falha do implante realça a necessidade de uma melhor compreensão biomecânica do sistema de implante femoral. Esta dissertação estuda como próteses
femorais se comportam quando feitas de diferentes materiais e como ocorre a deformação quando sujeita a uma carga típica. Para realizar este estudo realizaram-se duas aproximações distintas, uma numérica e outra experimental. Por digitalização da geometria da haste é obtido um modelo virtual da haste anatomicamente adaptada no software SolidWorks. A haste final foi impressa em 3D no laboratório FABLAB com PLA. Já o suporte da mesma foi fabricada por maquinagem numa fresadora CNC no laboratório de tecnologia mecânica. Foi utilizado o software de elementos finitos (ANSYS) para realizar as simulações numéricas. A geometria do fémur, tanto para os estudos experimentais como para os estudos de elementos finitos, foi baseada no fémur médio esquerdo. Posteriormente, foi realizado um ensaio de compressão no laboratório
de resistência dos materiais com o propósito de validar o campo de deformações medido com o sistema implementado, tendo como referência o campo de deformações obtido pelo método de elementos finitos. Na análise desenvolvida utilizou-se a técnica da Correlação Digital de Imagem por permitir a medição do campo de deformações com elevada resolução na região do implante. A partir das propriedades mecânicas medidas, para as mesmas condições de carregamento e de fronteira determinaram-se os campos de
deslocamento e deformação. A comparação da simulação numérica com os obtidos por via experimental permitiu validar as propriedades mecânicas determinadas a partir das medições computacionais, onde confirma-se a potencialidade deste tipo de ensaios para medições de campos de deslocamento e deformações.Total hip arthroplasty (THA) is a successful surgical technique that can be used for the effective treatment of femoral neck fractures, osteoarthritis, tumors, vascular necrosis, internal fixation failure, developmental dysplasia and rheumatoid arthritis. The large number of revision operations performed every year as a result of implant failure high-lights the need for a better biomechanical understanding of the femoral implant system.
This dissertation studies how femoral prostheses behave when made from different materials and how deformation occurs when subjected to a typical load. To carry out this study, two different approaches were taken, one numerical and the other experimental. By digitizing the stem geometry, a virtual model of the anatomically adapted stem is obtained in SolidWorks software. The final stem was 3D printed in the FABLAB laboratory using PLA. Its support was manufactured by machining on a CNC milling machine. Finite
element software (ANSYS) was used to carry out the numerical simulations. The geometry of the femur, for both the experimental and finite element studies, was based on the left middle femur. Subsequently, a compression test was carried out in the strength of materials laboratory in order to validate the deformation field measured with the implemented system, with the deformation field obtained by the finite element method as a reference. The Digital Image Correlation technique was used in the analysis because it allows the deformation field to be measured with high resolution in the implant region. Based on the mechanical properties measured, the displacement and deformation fields were determined for the same loading and boundary conditions. Comparison of the numerical simulation with the experimental results allowed the mechanical properties determined from the computational measurements to be validated, confirming the potential of this type of test for measuring displacement and deformation fields