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- Relatório final projeto landfoodPublication . Ribeiro, Luís Frölén; Farrero, Bernardo; Rossi da Silva, Paulo BrunoEste relatório técnico final elaborado pelo Instituto Politécnico de Bragança sobre as atividades desenvolvidas no projeto "LandFood" para a Landratech. Relata o desenvolvimento de um secador solar para a pré-secagem de bolotas no campo.
- The problem of the reliability of bending models for composite plates of medium thicknessPublication . Ribeiro, Luís Frölén; Rotko, Svitlana; Kuts, Nadiia; Zaharchuk, Victor; Shvabyuk, VolodymyrMost refined bending models of medium-thick plates, which consider transverse shear and partial compression deformations, differ little. However, despite a significant increase in the order of the governing differential equations, the results obtained from their equations give mainly a small increase in accuracy compared to the existing theories. On the other hand, such an increase in the order of the constructed systems of differential equations requires a significant increase in the effort required to solve them, complicates their physical interpretation, and narrows the range of people who can use them, primarily engineers and designers. Therefore, developing a plate-bending model that incorporates all the above factors and is on par with previously applied theories regarding the complexity of the calculation equations remains relevant. For example, most of the applied theories that do not consider transverse compression cannot be used to solve problems of contact interaction with rigid and elastic dies and bases because it is impossible to satisfy the conditions at the contact boundary of the outer surface of the plate, as well as the boundary conditions at the edges of the plate. Therefore, to provide guaranteed accuracy of the results, some researchers of these problems have introduced such a concept as “energy consistency” between the functions of representation of the displacement vector components, their number, the order of equations, and the number of boundary conditions. The authors, based on the developed version of the model of orthotropic plates of medium thickness, investigate the problem of taking into account the so-called “energy consistency” effect of the bending model, depending on the order of the design equations and the number of boundary conditions, as well as its usefulness and disadvantages in practical calculations. The equations of equilibrium in displacements and expressions for stresses in terms of force and moment forces are recorded. For rectangular and circular plates of medium thickness, test problems are solved, and the numerical data are compared with those obtained using spatial problems of elasticity theory, as well as the refined Timoshenko and Reissner theories. An analysis of the obtained results is provided.
- Product development and industrial processingPublication . Ribeiro, Luís Frölén; Ribeiro, J.E.; Costa, Carlos Casimiro da; Duarte, António; Andrade, Carlos A.R.; Svinth, Arne; Madsen, John; Thomsen, Morten; Smidstrup, Kent; Carsten, John JacobsenThis article aims at presenting a teaching experiment where the same course is taught simultaneously in two countries, Portugal at the Polytechnic Institute of Bragança (IPB) and Denmark, at Lillebaelt Academy (EAL). Project Based Learning (PBL) underlies the applied methodology. As the project is still in its initial phase it is too premature to delve into a conclusive and thus critical approach. Nonetheless, we will highlight the course methodological procedures and objectives as well as the educational gains to the students and to the two institutions involved.
- Heat pump dryer design optimization algorithmPublication . Andrade, Bernardo Campos; Amorim, Ighor Matheus Marques; Silva, Michel; Savosh, Larysa; Ribeiro, Luís FrölénDrying food involves complex physical atmospheric mechanisms with non-linear relations from the air-food interactions, and those relations are strongly dependent on the moisture contents and the type of food. Such dependence makes it complex to design suitable dryers dedicated to a single drying process. To streamline the design of a novel compact food-drying machine, a heat pump dryer component design optimization algorithm was developed as a subprogram of a Computer Aided Engineering tool. The algorithm requires inputting food and air properties, the volume of the drying container, and the technical specifications of the heat pump off-the-shelf components. The heat required to dehumidify the food supplied by the heat exchange process from condenser to evaporator, and the compressor’s requirements (refrigerant mass flow rate and operating pressures) are then calculated. Compressors can then be selected based on the volume and type of food to be dried. The algorithm is shown via a flow chart to guide the user through three different stages: Changes in drying air properties, heat flow within dryer and product moisture content. Example results of how different compressors are selected for different types of produces and quantities (Agaricus blazei mushroom with three different moisture contents or fish from Thunnini tribe) conclude this article.
- Stress and psychological well-being: study in parents of children with special needsPublication . Veiga-Branco, Augusta; Prada, Ana Raquel Russo; Antão, Celeste; Colomeischi, Adina; Ribeiro, Luís Frölén; Galvão, Ana MariaExisting research, mainly conducted with mothers, shows that families parenting a child special needs experience higher levels of emotional distress compared to families with children with a typical development (Delambo, et al, 2011; Lecavalier, et al, 2006, Lee, 2013). This is the first empirical research (to our knowledge) that will be conducted involving both parents of a child with special needs from the northern and interior region of Portugal. This quantitative, descriptive and cross-sectional research as the following aims: (i) to analyze the associations between parental stress and parents’ psychological well-being; (ii) to evaluate the influence of individual variables on parents’ psychological wellbeing. Data consisted of parents´ responses on the Portuguese version of the Parental Stress Scale (Mixão, Leal & Maroco, 2007) and Satisfaction with Life Scale (Simões, 1992). The survey will be conducted between the 15th of January and the 15th of March of 2017. Starting from the acquired consciousness about the fact the stress faced by families raising children SN may continue during adolescence and adult life, influencing the quality of family relationships on a long term, results will be presented. In fact, the relevance of the data obtained with families parenting children with special needs will be discussed considering the need of promoting the optimal development of parents with a child with special needs, in a short and long term in time.
- The problem of the reliability of bending models for composite plates of medium thicknessPublication . Shvabyuk, Vasyl; Rotko, Svitlana; Ribeiro, Luís Frölén; Kuts, Nadiia; Zaharchuk, Victor; Shvabyuk, VolodymyrMost refined bending models of medium-thick plates, which consider transverse shear and partial compression deformations, differ little. However, despite a significant increase in the order of the governing differential equations, the results obtained from their equations give mainly a small increase in accuracy compared to the existing theories. On the other hand, such an increase in the order of the constructed systems of differential equations requires a significant increase in the effort required to solve them, complicates their physical interpretation, and narrows the range of people who can use them, primarily engineers and designers. Therefore, developing a plate-bending model that incorporates all the above factors and is on par with previously applied theories regarding the complexity of the calculation equations remains relevant. For example, most of the applied theories that do not consider transverse compression cannot be used to solve problems of contact interaction with rigid and elastic dies and bases because it is impossible to satisfy the conditions at the contact boundary of the outer surface of the plate, as well as the boundary conditions at the edges of the plate. Therefore, to provide guaranteed accuracy of the results, some researchers of these problems have introduced such a concept as “energy consistency” between the functions of representation of the displacement vector components, their number, the order of equations, and the number of boundary conditions. The authors, based on the developed version of the model of orthotropic plates of medium thickness, investigate the problem of taking into account the so-called “energy consistency” effect of the bending model, depending on the order of the design equations and the number of boundary conditions, as well as its usefulness and disadvantages in practical calculations. The equations of equilibrium in displacements and expressions for stresses in terms of force and moment forces are recorded. For rectangular and circular plates of medium thickness, test problems are solved, and the numerical data are compared with those obtained using spatial problems of elasticity theory, as well as the refined Timoshenko and Reissner theories. An analysis of the obtained results is provided.
- Resilience and emotional regulation in parents of children with special needs (SN)Publication . Veiga-Branco, Augusta; Prada, Ana Raquel Russo; Antão, Celeste; Colomeischi, Adina; Ribeiro, Luís FrölénParents of children with Special Needs (SN) experience higher levels of emotional distress (Lecavalier, et al, 2006), depression (Benson, 2006), anxiety (Pakenham, et al, 2004) and social isolation. Informal caregiving of a child with SN is often regarded as a moral duty and most often research has focused primarily on the deficits and risk factors among these families. Based on the current assumptions of Positive Psychology (Seligman, 2000), the current research focus on Family Resilience and Emotional Competence (Bisquerra, 2000; Veiga-Branco 2004, 2005, 2007), assuming the potentially healthy and positive aspects of families in opposition to traditional psychology and the need to promote emotional skills within families. This study aims to recognize the association between family resilience and emotional regulation in parents with children with SN. Quantitative and cross-sectional study, gathered by face to face survey, that will be conducted between the 15th of January and the 15 th of March of 2017 on a representative sample both parents of a child with SN from the northern and interior region of Portugal. Family resilience, dyadic coping and emotional competence of the couple were measured, respectively, by Portuguese versions of the Family Resilience Assessment Scale (Martins, et al., 2013), the Dyadic Coping Inventory (Vedes et al., 2013) and the Emotional Skills and Competence Questionnaire (Lima Santos & Faria, 2005). The relevance of the data obtained with families parenting children with special needs will be discussed considering the need of promoting resilience within these families.
- Reduction of surface roughness by taguchi design: an approach for milling parametersPublication . Ribeiro, J.E.; Ribeiro, Luís FrölénThe quality performance of a machined product is measured by its geometric dimensioning and tolerancing as well as its surface roughness. The surface roughness should be as smooth as possible for the same price. This geometrical property depends on the combination of the machining parameters. The most important parameters are: feed rate, spindle speed, cutting axial and radial depths.
- Governance windscanner.PT national research infrastructure (PINFRA/22207/2016)Publication . Grosso, José; Campos, José; Ribeiro, Luís Frölén; Simões, TeresaThis document presents the governance structure foreseen for the operationalization of the WindScanner.PT research infrastructure. The methodology for the implementation of the governance structure, followed the one developed for the European Infrastructure WindScanner.EU, which was the origin of this Portuguese RI. However, as the European RI did not move forward due to a series of situations related to the infrastructure financing rules of the various members of the European consortium. In this sense the Portuguese consortium decided to maintain the project and adapt the RI structure to the Portuguese context and follow a simple model based on the usual research projects, and based on the governance structure defined for WindScanner.EU.
- Wind turbine blade waste: a quantifying modelPublication . Santos, Lucas Lisboa da Fonseca; Ribeiro, Luis FrölénThe growing trend of renewable energy, while helping decentralise and diversify the current energetic matrix, may also bring opportunities for improvement. Until today, a vital part of the wind turbine does not have a solidified disposal method in its afterlife. To better assess this issue, one needs to quantify it. A model based on actual wind turbine data enabled high accuracy estimation of the existing waste and predicted what will be generated in the industry's future. Between 2000 and 2014, the wind was the type of energy that registered the most considerable growth – not just among the renewable, but overall (15% more than second-placed gas) [1]. In the current European Union's plan to achieve net-zero emissions in its energy system by 2050, wind energy will play a relevant role: it expects a continuously grow in installed capacity of 17% until 2025, followed by a 12% one by 2030 [2]. However, what environmental impact can this measure and similar ones induce? Most wind turbine composition is from recyclable materials (94%); the issue lies in the remainder: the blades, mostly made of composites and resins – challenging to recycle materials [3]. One must take a step back and analyse some data to understand better how much of a concern it can become in the following years. In this paper, one analysed 357 distinct accurate wind turbine blade models from different manufacturers with rated power from 65 kW to 14 MW to attain enough data to create a model to predict the future waste generated by decommissioned wind turbine blades. The primary source of technical information was obtained through a wind turbine model database [4]. As a result, one developed a model to predict with a high resolution – compared to similar works from several authors – what the future holds regarding wind turbine blade waste. Instead of plotting all the data points in a scatter graph and using the resulting trendline to calculate an equation based on linear regression, the rated power range was divided into 10 intervals to offer a better resolution, Figure 1. One used a data set published by Wind Europe [5] as an exercise in the practical use of this model. In it, we have the total output of offshore wind turbines installed in Europe between 1995 and 2022. By applying the median (to filter outliers in the data) results seen on each rated power interval in Figure 2 to the number of installed turbines in the respective bin. One estimates the result of 27 years of wind turbine operations: 333.936,15 tons of waste with no current solution besides landfilling or incineration.