Transmission costs allocation based on optimal re-dispatch

Congestion management of transmission power systems has achieve high relevance in competitive environments, which require an adequate approach both in technical and economic terms. This paper proposes a new methodology for congestion management and transmission tariff determination in deregulated electricity markets. The congestion management methodology is based on a reformulated optimal power flow, whose main goal is to obtain a feasible solution for the re-dispatch minimizing the changes in the transactions resulting from market operation. The proposed transmission tariffs consider the physical impact caused by each market agents in the transmission network. The final tariff considers existing system costs and also costs due to the initial congestion situation and losses. This paper includes a case study for the 118 bus IEEE test case.

Re-use assessment of thermoset composite wastes as aggregate and filler replacement for concrete-polymer composite materials: a case study regarding GFRP pultrusion wastes

Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both the cross-linked nature of thermoset resins, which cannot be remoulded, and the complex composition of the composite itself, which includes glass fibres, polymer matrix and different types of inorganic fillers. Hence, to date, most of the thermoset based GFRP waste is being incinerated or landfilled leading to negative environmental impacts and additional costs to producers and suppliers. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, the effect of the incorporation of mechanically recycled GFRP pultrusion wastes on flexural and compressive behaviour of polyester polymer mortars (PM) was assessed. For this purpose, different contents of GFRP recyclates (0%, 4%, 8% and 12%, w/w), with distinct size grades (coarse fibrous mixture and fine powdered mixture), were incorporated into polyester PM as sand aggregates and filler replacements. The effect of the incorporation of a silane coupling agent was also assessed. Experimental results revealed that GFRP waste filled polymer mortars show improved mechanical behaviour over unmodified polyester based mortars, thus indicating the feasibility of GFRP waste reuse as raw material in concrete-polymer composites.

O empreendedorismo como opção de (re)inserção profissional

Este artigo procura evidenciar o empreendedorismo enquanto mecanismo de resposta à (re)inserção social, entendido enquanto necessidade ou oportunidade. Para além da apresentação do empreendedorsimo enquanto opção individual, destaca-se o papel que as universidades e institutos politécnicos devem assumir no desenvolvimento do espírito empreendedor no cluster dos recém-licenciados.

Deixem que eu me (re)encontre

O presente relatório reflete um projeto de investigação no âmbito do Mestrado em Educação e Intervenção Social, que assume como metodologia a Investigação Ação-Participativa, e que é desenvolvido e construído com um grupo de pessoas desempregadas. Assim, e contando com os participantes como co-construtores de todo o processo, foi necessário elaborar uma análise e caracterização da realidade da qual surgiram alguns problemas. É com base neles que o projeto começa a ser delineado, tendo por base a educação não-formal de adultos, e recorrendo a ações e atividades para se alcançarem os objetivos definidos e, desta forma, ser possível compreender qual o impacto que ele teve na vida dos participantes. Denominado por “Deixem que eu me (Re)Encontre”, este projeto de investigação pretendeu proporcionar momentos de desenvolvimento da autoestima, de redescoberta de capacidades e competências, e de criação de uma rede de suporte afetivo, estimulando nos participantes a apropriação de um poder de intervenção, gerador de mudança nas suas vidas, que há muito se tinha perdido.

Re-Use Assessment of Thermoset Composite Wastes as Aggregate and Filler Replacement for Concrete-Polymer Composite Materials: A case study regarding GFRP pultrusion wastes

Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both the cross-linked nature of thermoset resins, which cannot be remoulded, and the complex composition of the composite itself, which includes glass fibres, polymer matrix and different types of inorganic fillers. Hence, to date, most of the thermoset based GFRP waste is being incinerated or landfilled leading to negative environmental impacts and additional costs to producers and suppliers. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, the effect of the incorporation of mechanically recycled GFRP pultrusion wastes on flexural and compressive behaviour of polyester polymer mortars (PM) was assessed. For this purpose, different contents of GFRP recyclates (0%, 4%, 8% and 12%, w/w), with distinct size grades (coarse fibrous mixture and fine powdered mixture), were incorporated into polyester PM as sand aggregates and filler replacements. The effect of the incorporation of a silane coupling agent was also assessed. Experimental results revealed that GFRP waste filled polymer mortars show improved mechanical behaviour over unmodified polyester based mortars, thus indicating the feasibility of GFRP waste reuse as raw material in concrete-polymer composites.

Sustainability Improvement of a composite materials’ industry through recycling and re-engineering process approaches

Recent Advances in Mechanics and Materials in Design