Repositório IC-Online

Institution's Scientific Repository

IC-Online, the Institutional Repository of Scientific Information of the Polytechnic of Leiria (IPLeiria), is part of the RCAAP Project (Open Access Scientific Repositories of Portugal). Its main objectives are to organise, preserve and disseminate the scientific production of the Polytechnic of Leiria (IPLeiria), helping to increase the visibility and impact of the institution's scientific publications.

The IC-Online Repository includes various types of digital documents, such as articles from national and international scientific journals, papers from congresses and conferences, master's dissertations and doctoral theses, among others.

Política Institucional de Acesso Livre do Politécnico de Leiria (Despacho nº 124/2018)
Regras de afiliação do Politécnico de Leiria (Despacho nº 228/2020)
Normas de atribuição de identificadores DOI, ISBN e DL (Despacho nº 257/2024)
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Email repositorio@ipleiria.pt

Recent Submissions

Development of a new pultrusion equipment to manufacture thermoplastic matrix composite profiles

Publication . Novo, P.J.; Silva, J.F.; Van Hattum, F.W.J.; Marques, A.T.

This paper describes the design and manufacture of a low-cost full scale pultrusion prototype equipment and discusses the production and mechanical properties of polypropylene/glass (GF/PP) reinforced composite bars fabricated by using the prototype equipment. Three different GF/PP pre-impregnated raw-materials, a commercial GF/PP comingled system from Vetrotex, a GF/PP powder coated towpreg [1-3] and, a GF/PP pre-consolidated tape (PCT) produced in our laboratories, were used in the production of composite bars that were subsequently submitted to mechanical testing in order to determine the relevant mechanical properties and quantify the consolidation quality. Samples of the different composite profiles were also observed under SEM microscopy.

2012Conference paper

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An iterative uncoupling technique for the identification of the dynamic properties of joints

Publication . Batista, F. C.; Maia, N.M.M.

The identification of the dynamic properties of joints is a very important subject in structural dynamics. However, classic uncoupling methods are often very difficult to apply. In the present paper an iterative technique is proposed, trying to circumvent the well-known ill-conditioning problems that arise due to any small perturbations existing in the experimental data. Various cases are simulated and discussed to illustrate the technique, including situations where it is not possible to take measurements on the joint itself; the results are compared with the ones obtained with other methods.

2012Conference paper

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On the optimal shape of hip implants

Publication . Ruben, Rui; Fernandes, Paulo R.; Folgado, João

The success of a total hip arthroplasty is strongly related to the initial stability of the femoral component and to the stress shielding effect. In fact, for cementless stems, initial stability is essential to promote bone ingrowth into the stem coating. An inefficient primary stability is also a cause of thigh pain. In addition, the bone adaptation after the surgery can lead to an excessive bone loss and, consequently, can compromise the success of the implant. These factors depend on prosthesis design, namely on material, interface conditions and shape. Although, surgeons use stems with very different geometries, new computational tools using structural optimization methods have been used to achieve a better design in order to improve initial stability and therefore, the implant durability. In this work, a multi-criteria shape optimization process is developed to study the relationship between implants performance and geometry. The multi-criteria objective function takes into account the initial stability of the femoral stem and the effect of stress shielding on bone adaptation after the surgery. Then, the optimized stems are tested using a concurrent model for bone remodeling and osseointegration to evaluate long-term performance. Additionally, the sensitivity to misalignments is analyzed, since femoral stems are often placed in varus or valgus position. Results show that the different criteria are contradictory resulting in different characteristics for the hip stem. However, the multi-criteria formulation leads to compromise solutions, with a combination of the geometric characteristics obtained for each criterion separately.

2012-01Journal article

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Bond strength of textured micropiles grouted to concrete footings

Publication . Veludo, J.; Dias-da-Costa, D.; Júlio, E.N.B.S.; Pinto, P.L.

In a previous research study the authors performed push-out tests with smooth micropile inserts grouted under varying confinement conditions. It was shown that: (i) failure always occurs at the steel-to-grout interface; and (ii) the connection capacity increases with the passive confinement. To increase the connection capacity, it is a common practice to weld steel rings on the surface of the micropile and execute grooves in the predrilled hole. Therefore, a new study is herein presented aiming to widen the conclusions already drawn by analysing the influence of most important parameters in the bond strength of textured micropiles grouted to concrete footings. Laboratory tests were specifically designed for assessing the effect on the connection capacity of the: (i) diameter of the predrilled hole; (ii) insert’s embedment length; (iii) active confinement of the footing; and (iv) treatment of the hole surface. Eighteen textured micropile inserts grouted in RC footings were submitted to monotonic push-out tests until failure. In brief, it can be stated that the capacity of the micropile-to-footing connection increases by increasing the insert’s embedment length and by decreasing the hole diameter. Moreover, an adequate active confinement must be provided to achieve the required capacity.

2012-02Journal article

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Eficácia da Intervenção Precoce com Técnicas e Tecnologias Avançadas na Reabilitação de uma Fratura distal radiocubital: um estudo em Terapia da Mão

Publication . Vieira, Tiziana Lopes; Ribeiro, Jaime Emanuel Moreira; Roldão, Elisabete Jorge da Costa

As fraturas mais comuns nos membros superiores ocorrem na região distal do rádio e do cúbito. Nos adultos, resultam frequentemente de acidentes desportivos, rodoviários ou de trabalho, enquanto, nos idosos ocorrem, geralmente, devido a quedas. A Terapia Ocupacional, sobretudo a Terapia da Mão, desempenha um papel importante na reabilitação funcional da mão e do punho, garantindo o restabelecimento de todos os movimentos após um trauma ou lesão. Visa a reabilitação desde o acompanhamento pós-cirúrgico até a reaquisição da independência nas atividades do dia-a-dia. Recorre a atividades diferenciadas e dirigidas, assim como a recursos terapêuticos especializados, para que o indivíduo possa obter o máximo de independência possível. O recurso ao uso da tecnologia gamificada permite promover a reabilitação aliada ao entretenimento, potenciando efeitos na motivação e adesão à intervenção terapêutica e, consequentemente, incrementando resultados. A presente investigação teve como objetivo analisar a eficácia da intervenção precoce da Terapia Ocupacional/ Terapia da Mão desenvolvida em contexto hospitalar na área da reabilitação, através de um estudo de caso prospetivo de análise mista. O estudo descreve todo o processo de intervenção da Terapia Ocupacional/ Terapia da Mão, complementado com técnicas e tecnologias avançadas, aplicado a um participante do sexo masculino de 31 anos, com o diagnóstico de fratura radiocubital distal, submetido a redução cruenta e osteossíntese rígida. Após 12 semanas de intervenção, aquando da alta, o participante apresentou melhorias significativas em todas as competências avaliadas: melhoria do aspeto das cicatrizes e sensibilidade; diminuição do edema e da dor; aumento da força muscular, força de preensão manual e das pinças; das amplitudes de movimento; e a otimização do desempenho e da satisfação nas atividades identificadas como significativas pelo participante. As melhorias identificadas possibilitaram a reaquisição de independência nas Atividades de Vida Diária. É possível referir que a intervenção da Terapia Ocupacional/ Terapia da Mão, iniciada de forma imediata após o procedimento cirúrgico e complementada com a utilização de equipamentos com base tecnológica, conduziu a melhores resultados assim como a uma recuperação mais rápida.

2025-12-10Master thesis

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