12 documents found, page 1 of 2
Wheel-rail contact models in the presence of switches and crossings
Magalhães, H.; Marques, F.; Antunes, P.; Flores, P.; Pombo, João; Ambrósio, J.; Qazi, A.; Sebes, M.; Yin, H.; Bezin, Y.The development and implementation of wheel-rail contact models in multibody codes are two active research topics, aiming at improving the accuracy of numerical results and computational efficiency of the dynamics analysis. However, the realism of numerical results is challenged when considering switches and crossings (S&C), where the most adverse wheel-rail contact conditions occur. This paper presents a bench...
Ensino e aprendizagem à distância em tempos de COVID-19 um estudo com alunos do...
Flores, Maria Assunção; Veiga Simão, A. M.; Barros, A.; Flores, P.; Pereira, D.; Fernandes, E.; Ferreira, P.; Costa, L.A pandemia da COVID-19 desencadeou mudanças e efeitos sem precedentes nas instituições educativas. Também no ensino superior se assistiu a um processo rápido de transição do ensino presencial para o ensino remoto. Este estudo teve como objetivo conhecer as perceções dos estudantes do Ensino Superior sobre o ensino e a aprendizagem à distância durante o 2º semestre de 2019/2020 (n = 2718). Os dados foram recolhi...
An optimization approach to generate accurate and efficient lookup tables for e...
Magalhães, H.; Marques, F.; Liu, B.; Pombo, João; Flores, P.; Ambrósio, J.; Bruni, S.In a wide number of engineering applications, the interpolation of a lookup table (LUT) can substitute expensive calculations. The generation of a LUT consists of pre-calculating a set of quantities from a collection of points that covers the study domain where the interpolation is possible. Nevertheless, the selection of points where the exact calculation is performed is of utmost importance for the LUT size a...
An optimization approach to generate accurate and efficient lookup tables for e...
Magalhães, H.; Marques, F.; Liu, B.; Pombo, João; Flores, P.; Ambrósio, Jorge; Bruni, S.In a wide number of engineering applications, the interpolation of a lookup table (LUT) can substitute expensive calculations. The generation of a LUT consists of pre-calculating a set of quantities from a collection of points that covers the study domain where the interpolation is possible. Nevertheless, the selection of points where the exact calculation is performed is of utmost im-portance for the LUT size ...
O humor em manuais escolares de matemática
Menezes, L.; Ribeiro, A.; Oliveira, A. M.; Delplancq, V.; Gomes, H.; Martins, A. P.; Matos, I. A.; Viseu, Floriano; Flores, P.; Balula, J. P.O humor tem larga presença na vida das pessoas, combinando elementos afetivos e cognitivos com o intuito de bem-dispor. Para além dos contextos de lazer, o humor tem também sido utilizado em contextos associados ao trabalho, nomeadamente nas escolas, colocado ao serviço do ensino. Sendo os manuais escolares um recurso muito utilizado pelos professores, particularmente pelos de Matemática, pareceu-nos pertinente...
Humor in mathematics teaching
Menezes, Luís; Ribeiro, António; martins, ana patrícia; Santos vasconcelos gomes, Helena; Delplancq, Véronique; Balula, João Paulo; Matos, I. A.HUMOR: OUR VIEW FOR MATHEMATICS TEACHING Our assumptions and context. Process humor and be able to produce is clearly a sign of intelligence, revealing, when done well, complex reasoning. Humor has an important social role, assuming as a cognitive experience that as well as creating a sense of well-being, predisposes people to work and can improve the productivity of that work. Mathematics is a discipline in wh...
Obesity influence on perceived physical overload during vertical handling loads...
Colim, Ana S.; Arezes, P.; Flores, P.; Silva, S.Obesity prevalence is increasing among the Portuguese workforce, similarly to other industrial countries. Obesity seems to negatively affect the individuals’ work capacity. Tasks with vertical handling loads, including lifting and lowering, are very common in occupational contexts. With the aim of studying the possible effect of obesity on workers’ physical overload during vertical handling loads, psychophysica...
Influence of the contact model on the dynamic response of the human knee joint
Machado, M.; Flores, P.; Ambrosio, J.; Completo, A.The goal of this work is to study the influence of the contact force model, contact geometry, and contact material properties on the dynamic response of a human knee joint model. For this purpose, a multibody knee model composed by two rigid bodies, the femur and the tibia, and four non-linear spring elements that represent the main knee ligaments, is considered. The contact force models used were the Hertz, th...
Development of a biomechanical multibody knee model
Machado, M.; Flores, P.; Ambrósio, J.; Completo, A.The purpose of this work is to develop a mathematical model for the knee joint under the framework of multibody system dynamics. The model is composed by two bodies: the femur, which is stationary, and the tibia, which is considered to move relative to the femur. Due to their higher stiffness compared to that of the articular cartilages, the femur and tibia are modeled as rigid bodies. The articular cartilages ...
The importance of geometry and thickness for the conception of a new patellofem...
Castro, A.; Completo, A.; Simões, J. A.; Flores, P.One of the major reasons for the failure of currently available knee implants is the stress shielding effect. In loading situations, the bone is less requested, so the rate of bone remodeling decreases. The purpose for this work was to analyze the influence of the geometry and rigidity of the bone-implant interface on the stress shielding effect and on the stability of the prosthesis, applying the Finite Elemen...