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- Protocol for a cluster randomised trial of a goal-oriented care approach for multimorbidity patients supported by a digital platformPublication . Gil Conde, Margarida; Peyroteo, Mariana; Maria, Ana; Maia, Mélanie Raimundo; Gregório, João; Paulo, Marilia Silva; Alves, Marta; Papoila, Ana Luísa; Lapão, Luís Velez; Heleno, Bruno; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; DEMI - Departamento de Engenharia Mecânica e Industrial; NOVA Medical School|Faculdade de Ciências Médicas (NMS|FCM); Comprehensive Health Research Centre (CHRC) - pólo NMS; Instituto de Higiene e Medicina Tropical (IHMT); BMJ Publishing GroupIntroduction Health information systems represent an opportunity to improve the care provided to people with multimorbidity. There is a pressing need to assess their impact on clinical outcomes to validate this intervention. Our study will determine whether using a digital platform (Multimorbidity Management Health Information System, METHIS) to manage multimorbidity improves health-related quality of life (HR-QoL). Methods and analysis A superiority, cluster randomised trial will be conducted at primary healthcare practices (1:1 allocation ratio). All public practices in the Lisbon and Tagus Valley (LVT) Region, Portugal, not involved in a previous pilot trial, will be eligible. At the participant level, eligible patients will be people with complex multimorbidity, aged 50 years or older, with access to an internet connection and a communication technology device. Participants who cannot sign/read/write and who do not have access to an email account will not be included in the study. The intervention combines a training programme and a customised information system (METHIS). Both are designed to help clinicians adopt a goal-oriented care model approach and to encourage patients and carers to play a more active role in autonomous healthcare. The primary outcome is HR-QoL, measured at 12 months with the physical component scale of the 12-item Short Form questionnaire (SF-12). Secondary outcomes will also be measured at 12 months and include mental health (mental component Scale SF-12, Hospital Anxiety and Depression Scale). We will also assess serious adverse events during the trial, including hospitalisation and emergency services. Finally, at 18 months, we will ask the general practitioners for any potentially missed diagnoses. Ethics and dissemination The Research and Ethics Committee (LVT Region) approved the trial protocol. Clinicians and patients will sign an informed consent. A data management officer will handle all data, and the publication of several scientific papers and presentations at relevant conferences/workshops is envisaged. Trial registration number NCT05593835.
- Hybrid conceptual model for assessing quality, production and satisfaction (Squal4agri), in agricultural production units, in cape verdePublication . Simões, Elsa; Saraiva, Margarida; Basch, Gottlieb; Pires, António Ramos; Rosa, Álvaro; Chaleta, Elisa; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; Molecular Diversity Preservation International (MDPI)In Cape Verde, small family farming production suffers continuously from limited essential resources such as water and soil for a steady development. This situation is further aggravated by the lack of financial resources. We have developed a hybrid and multidimensional conceptual model for improvement of those small farming units by bringing together concepts of quality management, farmers’ satisfaction evaluation and production capabilities. The model we have built was the result of an inquiry based on Focus Group study with 15 farmers and it was carried out in 2019. We name the model as SQual4Agri and this is a step toward improvement in small family based agricultural organization, namely in productivity, responsibility sharing, communication and quality management.
- A Miniaturized Device Coupled with Digital Image Correlation for Mechanical TestingPublication . Cruz, Daniel J.; Xavier, José; Amaral, Rui L.; Santos, Abel D.; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; DEMI - Departamento de Engenharia Mecânica e Industrial; MDPI - Multidisciplinary Digital Publishing InstituteMiniaturized mechanical testing based on small sample testing technology is a powerful technique to characterize the mechanical properties of different materials, and it is being used in different application fields. However, the small size of the specimens poses several challenges because the results are highly sensitive to measurement accuracy and the corresponding mechanical properties can change substantially due to the so-called specimen size effect. In this work, a novel testing device based on miniaturized specimens is presented. The equipment is designed to test materials in tensile and compressive loadings, but it is also capable of performing reverse-loading tests. Buckling of the specimen is an inherent phenomenon in compression loadings, especially for thin materials. Therefore, specimen geometry is properly studied and optimized to mitigate this effect. To evaluate the deformation of the specimen, the digital image correlation (DIC) technique is used to capture the full-field strain in the central gauge section of the sample. A sensitivity analysis of the DIC setting parameters was performed for this application. To evaluate the performance of the developed system, experimental results of monotonic tests and tests with reverse loadings (tension-compression) are presented, considering two high-strength steels (DP500 and DP780).
- EBDFPublication . Nodehi, Tahereh; Zutshi, Aneesh; Grilo, António; Rizvanovic, Belma; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; DEMI - Departamento de Engenharia Mecânica e Industrial; ElsevierBlockchain technologies have seen a steady growth in interest from industries as the technology is gaining maturity. It is offering a novel way to establish trust amongst multiple stakeholders without relying or trusting centralised authorities. While its use as a decentralised store of value has been validated through the emergence of cryptocurrencies, its use case in industrial applications with multiple stakeholder ecosystems such as industrial supply chain management, is still at an early stage of design and experimentation where private blockchains are used as opposed to public blockchains. Many enterprise blockchain projects failed to gain traction after initial launches, due to inefficient design, lack of incentives to all stakeholders or simply because the use of blockchain was not really necessary in the first place. There has been a need for a framework that allows blockchain designers and researchers to evaluate scenarios when a blockchain solution is useful and design the key configurations for an enterprise blockchain solution. Literature on blockchain architectures are sparse and only applicable to specific use cases or functionalities. This paper proposes a comprehensive Enterprise Blockchain Design Framework (EBDF), that not only identifies the relevant use cases when a blockchain must be utilised, but also details all the characteristics and configurations for designing an enterprise blockchain ecosystem, applicable to multiple industries. To validate the EBDF, we apply the same to the Vortal e-Procurement ecosystem allowing for multiple platforms to interoperate with greater transparency and accountability over the proposed blockchain framework. In this use case, many vendors bid for procurement procedures, often for publicly managed funds where it is extremely vital that full transparency and accountability is ensured in the entire process. Ensuring that certain digital certification functions, such as timestamps are independent from e-Procurement platform owners has been a challenge. Blockchain technology has emerged as a promising solution for not only ensuring transparency and immutability of records, but also providing for interoperability across different platforms by acting as a trusted third-party. The applied framework is used to design a Hyperledger based blockchain solution with some of the key architectural elements that could fulfil these needs while presenting the advantages of such a solution.
- Bi-Objective Optimization Problems—A Game Theory Perspective to Improve Process and ProductPublication . Costa, Nuno; Lourenço, João; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; Molecular Diversity Preservation International (MDPI)Cost-effective manufacturing processes or products are no longer the only requirements for business sustainability. An approach based on Game Theory is suggested to find solutions for bi-objective problems. In particular, Stackelberg’s technique is employed and complemented with the Factors Scaling tool to help the users in defining its strategy for optimizing process and product quality characteristics. No subjective information (shape factors, weights, and/or any other preference information) is required from the users, and basic computational background is enough for implementing it. Two case studies provide evidence that the suggested easy-to-use approach can yield nondominated solutions from a small number of Leader–Follower cycles, what reinforces its usefulness for bi-objective optimization problems.
- LES validation of lock-exchange density currents interacting with an emergent bluff obstaclePublication . Brito, M.; Ferreira, R. M. L.; Sousa, A.; Farias, R.; Lollo, G. Di; Ricardo, A. M.; Gil, L.; DEMI - Departamento de Engenharia Mecânica e Industrial; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; SpringerWe address the capability of large eddy simulation (LES) to predict the physics of density currents interacting with bluff obstacles. Most density currents of interest in engineering and geophysical applications interact with obstacles or topographic features. Validating LES solutions in these contexts is crucial to establish it as a trusted tool. We thus propose a validation effort based on simple geometries that nonetheless pose challenges common to more complex systems, including boundary layer separation and convective instabilities. We focus on lock-exchange gravity currents in the slumping phase interacting with an emergent vertical circular cylinder. Our main investment was in ensuring that the comparison of experimental data and numerical results include, at least, the velocity and the density fields , and derived quantities (e.g., second order moments). Measurements of both density and velocity fields were performed in the side and plan views for cylinder Reynolds numbers, Red, in the range 1300 to 3475. It was found that the LES accurately predicts the temporal evolution of the current front position. The computed front velocity exhibits a maximum relative error less than 8%. A good agreement between the LES and the experimental size and shape of the current head, and billows was found. The overall features upstream the cylinder, including a reflected wave, adverse pressure gradient and backflow, and downstream the cylinder, including the backflow, wake and the formation of a new head are well reproduced by LES. The agreement between the LES and the experimental time-space evolution of current spanwise- and depth-averaged density contours and the instantaneous velocity fields are not affected by Red.
- On the use of the cumulative strain energy density for fatigue life assessment in advanced high-strength steelsPublication . Branco, R.; Martins, R. F.; Correia, J. A.F.O.; Marciniak, Z.; Macek, W.; Jesus, J.; DEMI - Departamento de Engenharia Mecânica e Industrial; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; ELSEVIER SCI LTDIn this paper, the applicability of the cumulative strain energy density is explored as a fatigue indicator parameter for advanced high-strength steels subjected to strain-controlled conditions. Firstly, the cyclic stress–strain responses of nine steels, selected from three multiphase families, encompassing different elemental compositions and different heat treatment routes, were studied. Then, the predictive capabilities of the proposed model were compared with those of other strain-based and energy-based approaches. It was found that the cumulative strain energy density decreases as the strain amplitude increaes. It was also found that the cumulative strain energy density and the fatigue life can be related via a power function. In addition, the relationship between the cumulative strain energy and the fatigue life was not significantly affected by the elemental composition or the heat treatment route. Finally, the fatigue lives computed through the cumulative strain energy density concept were close to those of the other models but were slightly more conservative.
- Energy SustainabilityPublication . Flores, João; Cavique, Miguel; Seixas, Júlia; DCEA - Departamento de Ciências e Engenharia do Ambiente; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; CENSE - Centro de Investigação em Ambiente e Sustentabilidade; Molecular Diversity Preservation International (MDPI)Energy Sustainability has been addressed through advancing technology efficiency, which may increase the impact of the use of natural resources. However, the increase in efficiency makes services cheaper, which causes a rebound effect, direct or indirect, on energy consumption and materials. Moreover, the popular concept of recycling seems insufficient to reduce the use of critical raw materials to provide energy services. From the perspective of the Earth’s limited resources, the sustainability problem needs a design approach to tackle the rebound effect from efficiency. This work aims to create a theoretical holistic review regarding energy use linked to technology efficiency, to understand how rebound effects may be prevented. In this work, the Axiomatic Design (AD) theory creates the framework that defines the Energy Sustainability functions and identifies the couplings that create the rebounds. According to AD, cycles occur on coupled designs, classified as poor designs. Decoupling the design clarifies two possible and complementary policies to achieve sustainability goals regarding the use of resources. The first is the circular economy, with constraints on energy and raw materials. The second is the massive use of local renewable energies. Plausible solutions come from mandating efficiency and taxation, dematerializing the economy, and reducing, reusing, remanufacturing, and recycling materials from products and systems. These solutions impact economic, environmental, and societal behaviors. The novelty of this approach is the definition of a system model for Energy Sustainability in the frame of AD, while tackling the rebound effect from technological efficiency.
- Multi-material and strength-oriented microstructural topology optimization applied to discrete phase and functionally graded materialsPublication . Conde, Fábio M.; Coelho, Pedro G.; Guedes, José M.; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; Springer Science Business MediaStructural optimization plays an important role in lightweight construction, and stresses need to be controlled to avoid material failure. The multi-material design setting offers additional design freedom which can lead to structures with improved strength and stiffness properties compared to the single-material case. The present work addresses topology optimization of a periodic composite material unit cell, with properties predicted by homogenization, using strength and stiffness design criteria, under bulk and mixed loading cases. Plane stress and linear behavior are assumed. The compliance minimization with mass constraint problem is revisited here, but the paper focus is on multi-material stress-based topology optimization. Specifically, the maximal von Mises stress is minimized in the unit-cell where two solids are mixed amidst void. Depending on the material interpolation law settings, two design solutions are investigated. On one hand, the two solids coexist being bonded together across sharp interfaces. On the other hand, a functionally graded material is obtained as an extensive smooth variation of material properties on account of varying composition’s volume fractions of both solids throughout the design domain. A parallel MMA version is proposed to efficiently deal with several design constraints. The compliance-based optimization results show that multi-material microstructures can be stiffer compared to single-material ones for the same mass requirement. Regarding the stress-based problem, lower stress peaks are obtained in bi-material design solutions and, specially, in the case of graded material solutions. The latter approximates a fully stressed design which excels in stress mitigation. Therefore, the multi-material setting impacts favorably on structural performance, in both stiffness and strength-oriented designs.
- Development of a Computational Model for Investigation of and Oscillating Water Column Device with a Savonius TurbinePublication . dos Santos, Amanda Lopes; Fragassa, Cristiano; Santos, Andrei Luís Garcia; Vieira, Rodrigo Spotorno; Rocha, Luiz Alberto Oliveira; Conde, José Manuel Paixão; Isoldi, Liércio André; dos Santos, Elizaldo Domingues; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; MDPI - Multidisciplinary Digital Publishing InstituteThe present work aims to develop a computational model investigating turbulent flows in a problem that simulates an oscillating water column device (OWC) considering a Savonius turbine in the air duct region. Incompressible, two-dimensional, unsteady, and turbulent flows were considered for three different configurations: (1) free turbine inserted in a long and large channel for verification/validation of the model, (2) an enclosure domain that mimics an OWC device with a constant velocity at its inlet, and (3) the same domain as that in Case 2 with sinusoidal velocity imposed at the inlet. A dynamic rotational mesh in the turbine region was imposed. Time-averaged equations of the conservation of mass and balance of momentum with the k–ω Shear Stress Transport (SST) model for turbulence closure were solved with the finite volume method. The developed model led to promising results, predicting similar time–spatial-averaged power coefficients (CP ) as those obtained in the literature for different magnitudes of the tip speed ratio (0.75 ≤ λ ≤ 2.00). The simulation of the enclosure domain increased CP for all studied values of λ in comparison with a free turbine (Case 1). The imposition of sinusoidal velocity (Case 3) led to a similar performance as that obtained for constant velocity (Case 2).