Projeto de estrutura variante de um edifício de habitação na zona de Lisboa

Trabalho de Projeto para obtenção do grau de Mestre em Engenharia Civil na Área de Especialização de Estruturas

O auteur a ver-se a si mesmo ao espelho: as alegorias do enunciador em Jean Cocteau

ABSTRACT - Jean Cocteau, French cinema auteur avant la lettre, has consecrated his uniqueness to the defense of the “poet” and the promotion of its artistic ideals, before the French Nouvelle Vague inspired the break away from the filmic tradition and ahead of the eulogistic tendency to consider the director the undisputed creative entity of the filmmaking process. The Orphic trilogy expresses Cocteau’s cinematic philosophy in action. In other words, it reveals the way by which the creative entity affirms itself as the major filmic enunciator, through an allegorical relationship with vision. Therefore, Cocteau’s self-reflexive metacinema conjoins, in a fertile attunement, the starting point and the ultimate goal, the creation and the reception. Without being exactly a cinema about the cinema, this artistic practice is, nonetheless, very much with the cinema, feeding as it does on its essence. The films Le Sang d’un poète (“The Blood of a Poet”, 1932), Orphée (“Orpheus”, 1950) and Le Testament d’Orphée, ou ne me demandez pas pourquoi! (“Testament of Orpheus”, 1960) recreate, in allegorical form, the double creative function: the look of the directing entity reflects the gaze of the observer, just as this one always restores the presence of the creator. In short: Cocteau’s films, more than anyone else’s, deliberately reflect its auteur as enunciator.

Heterophoria, fusional amplitudes and stereoacuity in school aged children

The stability of binocular vision depends on good fusional amplitudes and its measurements provide information about the patient’s ability to cope with a deviation. However, weak correlations between fusional amplitudes and angle of deviation have been reported in the literature. There are no uniform normative values of fusional amplitudes, even though standards for vergence have been established since 1940s. Aims: 1) Determine the prevalence of heterephoria; 2) Determine the relationship between heterophoria, fusional amplitudes and stereoacuity in children.

Logic functions based on optical bias controlled SIC Tandem devices

The purpose of this paper is the design of an optoelectronic circuit based on a-SiC technology, able to act simultaneously as a 4-bit binary encoder or a binary decoder in a 4-to-16 line configurations and show multiplexer-based logical functions. The device consists of a p-i'(a-SiC:H)-n/p-i(a-Si:H)-n multilayered structure produced by PECVD. To analyze it under information-modulated wave (color channels) and uniform irradiation (background) four monochromatic pulsed lights (input channels): red, green, blue and violet shine on the device. Steady state optical bias was superimposed separately from the front and the back sides, and the generated photocurrent was measured. Results show that the devices, under appropriate optical bias, act as reconfigurable active filters that allow optical switching and optoelectronic logic functions development providing the possibility for selective removal of useless wavelengths. The logic functions needed to construct any other complex logic functions are the NOT, and both or either an AND or an OR. Any other complex logic function that might be found can also be used as building blocks to achieve the functions needed for the retrieval of channels within the WDM communication link. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Strap repair optimization by using embedded patches

Adhesively-bonded techniques offer an attractive option for repair of aluminium structures, and currently there are three widely used configurations, i.e., single-strap (SS), double-strap (DS) and scarf repairs. SS and DS repairs are straightforward to execute but stresses in the adhesive layer peak at the ends of the overlap. DS repairs additionally require both sides of the damaged structures to be reachable for repair, which is often not possible. In these repair configurations, some limitations emerge such as the weight, aerodynamic performance and aesthetics. The scarf repair is more complex to fabricate but stresses are more uniform along the adhesive bondline. Few studies of SS and DS repairs with embedded patches, such that these are completely flush with the adherends, are available in the literature. Furthermore, no data is available about the effects of geometrical and material parameters (e.g. the Young’s modulus of adhesive, E) on the mechanical behaviour optimization of embedded repairs. For this purpose, in this work standard SS and DD repairs, and also with embedded patches in the adherends, were tested under tension to allow the geometry optimization, by varying the overlap length (LO), thus allowing the maximization of the repairs strength. The influence of the patch embedding technique, showing notorious advantages such as aerodynamic or aesthetics, was compared in strength with standard strap repairs, for the viability analysis of its implementation. As a result of this work, some conclusions were drawn for the design optimization of bonded repairs on aluminium structures.

Numerical and experimental study of tensile strength of single and double-strap repairs

Adhesive bonding as a joining or repair method has a wide application in many industries. Repairs with bonded patches are often carried out to re-establish the stiffness at critical regions or spots of corrosion and/or fatigue cracks. Single and double-strap repairs (SS and DS, respectively) are a viable option for repairing. For the SS repairs, a patch is adhesively-bonded on one of the structure faces. SS repairs are easy to execute, but the load eccentricity leads to peel peak stresses at the overlap edges. DS repairs involve the use of two patches, one on each face of the structure. These are more efficient than SS repairs, due to the doubling of the bonding area and suppression of the transverse deflection of the adherends. Shear stresses also become more uniform as a result of smaller differential straining. The experimental and Finite Element (FE) study presented here for strength prediction and design optimization of bonded repairs includes SS and DS solutions with different values of overlap length (LO). The examined values of LO include 10, 20 and 30 mm. The failure strengths of the SS and DS repairs were compared with FE results by using the Abaqus® FE software. A Cohesive Zone Model (CZM) with a triangular shape in pure tensile and shear modes, including the mixed-mode possibility for crack growth, was used to simulate fracture of the adhesive layer. A good agreement was found between the experiments and the FE simulations on the failure modes, elastic stiffness and strength of the repairs, showing the effectiveness and applicability of the proposed FE technique in predicting strength of bonded repairs. Furthermore, some optimization principles were proposed to repair structures with adhesively-bonded patches that will allow repair designers to effectively design bonded repairs.

Compact SMB chromatography for binary separation

A thesis submitted for the degree of Doctor of Philosophy

InOx thin films deposited by plasma assisted evaporation: application in light shutters

An integration of undoped InOx and commercial ITO thin films into laboratory assembled light shutter devices is made. Accordingly, undoped transparent conductive InOx thin films, about 100 nm thick, are deposited by radiofrequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium teardrops with no intentional heating of the glass substrates. The process of deposition occurs at very low deposition rates (0.1-0.3 nm/s) to establish an optimized reaction between the oxygen plasma and the metal vapor. These films show the following main characteristics: transparency of 87% (wavelength, lambda = 632.8 nm) and sheet resistance of 52 Omega/sq; while on commercial ITO films the transparency was of 92% and sheet resistance of 83 Omega/sq. The InOx thin film surface characterized by AFM shows a uniform grain texture with a root mean square surface roughness of Rq similar to 2.276 nm. In contrast, commercial ITO topography is characterized by two regions: one smoother with Rq similar to 0.973 nm and one with big grains (Rq similar to 3.617 nm). For the shutters assembled using commercial ITO, the light transmission coefficient (Tr) reaches the highest value (Tr-max) of 89% and the lowest (Tr-min) of 1.3% [13], while for the InOx shutters these values are 80.1% and 3.2%, respectively. Regarding the electric field required to achieve 90% of the maximum transmission in the ON state (E-on), the one presented by the devices assembled with commercial ITO coated glasses is 2.41 V/mu m while the one presented by the devices assembled with InOx coated glasses is smaller, 1.77 V/mu m. These results corroborate the device quality that depends on the base materials and fabrication process used. (C) 2014 Elsevier Ltd. All rights reserved.

Design optimization of cruciform specimens for biaxial fatigue loading

In order to correctly assess the biaxial fatigue material properties one must experimentally test different load conditions and stress levels. With the rise of new in-plane biaxial fatigue testing machines, using smaller and more efficient electrical motors, instead of the conventional hydraulic machines, it is necessary to reduce the specimen size and to ensure that the specimen geometry is appropriated for the load capacity installed. At the present time there are no standard specimen’s geometries and the indications on literature how to design an efficient test specimen are insufficient. The main goal of this paper is to present the methodology on how to obtain an optimal cruciform specimen geometry, with thickness reduction in the gauge area, appropriated for fatigue crack initiation, as a function of the base material sheet thickness used to build the specimen. The geometry is optimized for maximum stress using several parameters, ensuring that in the gauge area the stress is uniform and maximum with two limit phase shift loading conditions. Therefore the fatigue damage will always initiate on the center of the specimen, avoiding failure outside this region. Using the Renard Series of preferred numbers for the base material sheet thickness as a reference, the reaming geometry parameters are optimized using a derivative-free methodology, called direct multi search (DMS) method. The final optimal geometry as a function of the base material sheet thickness is proposed, as a guide line for cruciform specimens design, and as a possible contribution for a future standard on in-plane biaxial fatigue tests. © 2014, Gruppo Italiano Frattura. All rights reserved.

Bertrand oligopoly when rivals' costs are unknown

We study a Bertrand oligopoly model with incomplete information about rivals' costs, where the uncertainty is given by a uniform distribution. We compute the Bayesian-Nash equilibrium of this game, the ex-ante expected profit and the ex-post profit of each firm. We see that, even though only one firm produces in equilibrium, all firms have a positive ex-ante expected profit.

Bertrand and Cournot oligopolies when rivals' costs are unknown

We study Bertrand and Cournot oligopoly models with incomplete information about rivals’ costs, where the uncertainty is given by a uniform distribution. We compute the Bayesian- Nash equilibrium of both games, the ex-ante expected profits and the ex-post profits of each firm. We see that, in the price competition, even though only one firm produces in equilibrium, all firms have a positive ex-ante expected profit.

Patterns of Associational Life in Western Europe, 1800-2000

Thesis submitted for assessment with a view to obtaining the degree of Doctor of Political and Social Science of the European University Institute

Redox-active cytotoxic diorganotin(IV) cycloalkylhydroxamate complexes with different ring sizes: Reduction behaviour and theoretical interpretation

Two series of new diorganotin(IV) cycloalkylhydroxamate complexes with different ring sizes (cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl), formulated as the mononuclear [R2Sn(HL)(2)] (1:2) (a, R=Bu-n and Ph) and the polymeric [R2SnL](n) (1:1) (b, R=Bu-n) compounds, were prepared and fully characterized. Single crystal X-ray diffraction for [(Bu2Sn)-Bu-n{C5H9C(O)NHO}(2)] (3a) discloses the cis geometry and strong intermolecular NH center dot center dot center dot O interactions. The in vitro cytotoxic activities of the complexes were evaluated against HL-60, Bel-7402, BGC-823 and KB human tumour cell lines, the greater activity concerning [(Bu2Sn)-Bu-n(HL)(2)] [HL=C3H5C(O)NHO (1a), C6H11C(O)NHO (4a)] towards BGC-823. The complexes undergo, by cyclic voltammetry and controlled-potential electrolysis, one irreversible overall two-electron cathodic process at a reduction potential that does not appear to correlate with the antitumour activity. The electrochemical behaviour of [R2Sn(C5H9C(O)NHO)(2)] [R=Bu-n (3a), Ph (7a)] was also investigated using density functional theory (DFT) methods, showing that the ultimate complex structure and the mechanism of its formation are R dependent: for the aromatic (R = Ph) complex, the initial reduction step is centred on the phenyl ligands and at the metal, being followed by a second reduction with Sn-O and Sn-C ruptures, whereas for the alkyl (R=Bu-n) complex the first reduction step is centred on one of the hydroxamate ligands and is followed by a second reduction with Sn-O bond cleavages and preservation of the alkyl ligands. In both cases, the final complexes are highly coordinative unsaturated Sn-II species with the cis geometry, features that can be of biological significance.

A stochastic programming approach for the development of offering strategies for a wind power producer

A stochastic programming approach is proposed in this paper for the development of offering strategies for a wind power producer. The optimization model is characterized by making the analysis of several scenarios and treating simultaneously two kinds of uncertainty: wind power and electricity market prices. The approach developed allows evaluating alternative production and offers strategies to submit to the electricity market with the ultimate goal of maximizing profits. An innovative comparative study is provided, where the imbalances are treated differently. Also, an application to two new realistic case studies is presented. Finally, conclusions are duly drawn.

Diagnóstico de funcionamento e otimização das ETARs do concelho da Póvoa de Varzim

O tratamento das águas residuais é uma matéria de extrema importância para o município da Póvoa de Varzim, não só por uma questão de saúde pública e conservação do meio ambiente como também pela vertente turística deste concelho, que tem na sua orla costeira seis praias às quais foram atribuídas bandeiras azuis pela sua qualidade. O concelho da Póvoa de Varzim engloba doze freguesias e possui quinze estações de tratamento de águas residuais (ETARs), sendo catorze delas compactas. O seu controlo é assegurado pela divisão de saneamento básico da câmara municipal da Póvoa de Varzim. O objetivo deste trabalho foi o diagnóstico de funcionamento das ETARs do município tendo em vista a identificação dos problemas existentes e a sua resolução/otimização. De forma a poder identificar o princípio de funcionamento e a presença de anomalias nas estações de tratamento, foram realizadas várias visitas a cada uma delas ao longo do período de estágio. A recolha de amostras para análises dos diferentes parâmetros foi feita por um funcionário e estas foram enviadas para o laboratório com parceria com a Câmara Municipal. Após uma extensa recolha de informação no local e de um estudo exaustivo de toda a documentação associada a cada ETAR concluiu-se que apenas quatro delas apresentavam problemas revelantes. As ETARs do parque industrial de Laúndos e do centro histórico de Rates apresentam caudais de admissão bastante elevados devido à descarga pontual de camiões cisterna o que faz com que o tratamento não seja eficaz. Como solução sugeriu-se a construção de um tanque de equalização em ambas as ETARs, com agitador e regulador de caudal, de forma a garantir, respetivamente, a mistura e uniformização das águas residuais domésticas e industriais e que apenas será bombeado o caudal adequado para tratamento. As ETARs da Incondave e das Fontaínhas apresentam sobretudo anomalias a nível do equipamento, o que leva a um mau desempenho da instalação. Aconselhou-se o conserto dos equipamentos danificados e uma inspeção mais frequente das instalações para que mal ocorra uma avaria, esta seja reparada o mais depressa possível. O estágio na câmara municipal da Póvoa de Varzim (CMPV) teve a duração de 10 meses, entre Outubro e Julho de 2012 e foi realizado no âmbito da disciplina de dissertação/ estágio do mestrado de tecnologias de proteção ambiental no Instituto Superior de Engenharia do Porto. Este estágio foi uma mais-valia para mim na medida em que pude consolidar os conhecimentos adquiridos ao longo de todo o meu percurso académico e conhecer a realidade do mercado de trabalho.