Acknowledging the goal of reduced aircraft weight, there is a need to improve on conservative design techniques used in industry. Minimisation of laminate in-plane elastic energy is used as an appropriate in-plane performance marker to assess the weight saving potential of new design techniques. MATLAB optimisations using a genetic algorithm were used to find the optimal laminate variables for minimum in-plane elastic energy and/or damage tolerance for all possible loadings. The use of non-standard angles was able to offer equivalent, if not better in-plane performance than standard angles, and are shown to be useful to improve the ease of manufacture. Any standard angle laminate stiffness was shown to be able to be matched by a range of two non-standard angle ply designs. This non-uniqueness of designs was explored. Balancing of plus and minus plies about the principal loading axes instead of themanufacturing axes was shown to offer considerable potential for weight saving as the stiffness is better aligned to the load. Designing directly for an uncertain design load showed little benefit over the 10% ply percentage rule in maintaining in-plane performance. This showed the current rule may do a sufficient job to allow robustness in laminate performance. This technique is seen useful for non-standard angle design that lacks an equivalent 10% rule. Current use of conservative damage tolerance strain limits for design has revealed the need for more accurate prediction of damage propagation. Damage tolerance modelling was carried out using fracture mechanics for a multi-axial loading considering the full 2D strain energy and improving on current uni-axial models. The non-conservativeness of the model was evidenced to be from assumptions of zero post-buckled stiffness. Preliminary work on conservative multi-axial damage tolerance design, independent of thickness, is yet to be confirmed by experiments.

This thesis concerns the introduction and development in our laboratory of a multilayer ceramic technology, called LTCC, for RF and microwave packaging. LTCC stands for Low Temperature Co-fired Ceramics. As can be understood from its name, the low temperature means that the LTCC circuit is fired below 1000 °C that allows the use of high conductivity materials such as gold and silver. The thesis work starts after the bibliographic study of RF packaging technology, with the choice of LTCC substrate and conductor materials necessary to implement LTCC technology in our laboratory. Then, the LTCC manufacturing process is put in place and validated in order to produce operational LTCC circuits. This process includes the cut of LTCC layers, via hole and cavity creation, via fill for vertical interconnecting, screen printing for horizontal patterns, stacking, lamination and finally the firing to obtain a 3D circuit. Most encountered technological problems are resolved and the fabrication steps are validated. LTCC DESIGN RULES that contain all dimensional values required for future RF packaging designers at the laboratory is elaborated. Next, after the successful establishment of LTCC technology, it is qualified up to 40 GHz using simple RF structures such as transmission lines and planar resonators. Then, a multilayer LTCC package for an MMIC oscillator functioning in the frequency band between 10.6 and 12.6 GHz is proposed, fabricated and finally measured.

La ventilation naturelle est une stratégie passive qui permet l'échange naturel d'air entre le bâtiment et l'environnement extérieur. Elle assure une bonne qualité de l'air intérieur, améliore le confort thermique et elle réduit les besoins énergétiques, les émissions de gaz à effet de serre et les symptômes liés au syndrome du bâtiment malsain. Bien que les avantages et les bénéfices de la ventilation naturelle soient multiples, son usage est rare dans l'architecture contemporaine. Bien sûr, il existe des limites à sa mise en œuvre dans certains bâtiments, comme la mauvaise qualité de l'air extérieur, mais ces problèmes ne justifient pas une utilisation si peu répandue. La cause de sa faible diffusion est principalement liée à la difficulté de la conception plutôt que aux facteurs physiques liés à l'environnement. La thèse vise à fournir différents outils pour comprendre la dynamique des fluides dans les bâtiments et développer des techniques et des méthodes pour aider la conception des bâtiments ventilés naturellement. L'approche adoptée dans la thèse est modélisée selon les besoins du concepteur qui peut choisir d'utiliser différents types de supports tels que: utiliser des outils graphiques ou des modélisations numériques, s'inspirer de l'architecture contemporaine et répéter les solutions technologiques existantes, utiliser des outils de modélisation physique, s'inspirer du passé ou du monde naturel. Ici plusieurs aspects de la ventilation naturelle sont traités en apportant à chacun une contribution innovante afin de créer des outils d'aide pour différents phases de la conception : Les objectifs de la thèse sont de créer des outils innovants qui simplifient la conception à des niveaux différents. Nous avons créé donc, des outils et des modèles graphiques simplifiés pour choisir la forme du bâtiment et son orientation, des lignes directrices pour le dimensionnement des dispositifs de ventilation (cheminées de toit), des méthodes expérimentales simplifiées associées à des codes de lecture des écoulements d'air. Nous avons également élargit le panorama culturel et historiques et nous avons créé des indications morphologiques dérivant de l'analyse de l'architecture biomimétique. Grâce à une analyse CFD paramétrique, des outils graphiques sont générés pour évaluer, de manière comparative, les performances de ventilation d'une famille morphologique de bâtiments et choisir la forme du bâtiment, son orientation et la position des ouvertures. Nous créons des lignes directrices pour la conception et le pré-dimensionnement des dispositifs de ventilation. Les règles sont déterminées par une analyse comparative de neuf projets de bâtiments contemporains ventilés naturellement dans lesquels le dispositif de ventilation est présent. Une soufflerie est conçue et réalisée pour simplifier les visualisations des écoulements d'air autour des modèles de bâtiments et nous proposons une méthode pour réaliser des expérimentations de support à la conception. Le système de refroidissement géothermique d'une ancienne villa à Costozza (Vicence, Italie) est étudié. Cette section élargit la connaissance du patrimoine architectural italien et souligne l'importance de redécouvrir des solutions technologiques bioclimatiques existantes, toujours en fonction. On analyse une structure animale: le nid d'un insecte. Il s'agit d'un archétype bioclimatique qu'il peut être utilisé dans l'architecture en tant que technologie biomimétique / Natural ventilation is a passive ventilation strategy of confined spaces that consists of natural air exchange between the building and the outdoor environment. Natural ventilation ensures a good indoor air quality, it improves the thermal comfort and it reduces the greenhouses gases emission, the energy demand and the symptoms associated with the Sick Building Syndrome. Although the advantages and benefits of natural ventilation are multiple, its application is rare to contemporary architecture. By the way, there are some limits to its implementation, such as the bad quality of outdoor air, but that does not justify a so limited design of naturally ventilated buildings. The cause of its rare diffusion is primarily the difficulty of design rather than the factors related to the environment. The thesis intends to provide multiple tools for understanding the fluid dynamics in buildings and to develop techniques and methods to support the design of naturally ventilated buildings. The approach adopted in the thesis is modeled according to the needs of the designer. In fact, a designer can choose to use different types of support tools such as: use of graphic tools or numerical models, inspiration to contemporary architecture to provide the existing technology solutions, use of physical modeling tools, inspiration to the past or to the nature. Often, the design is a global process and does not need a single tool but the designer uses more than one. Here, several aspects of natural ventilation are dealt with, trying to make an innovative contribution to each of these themes, in particular : Through a parametric CFD analysis, graphical tools are generated to evaluate, adopting a comparative approach, the ventilative performance of a morphological family of buildings and to choose the shape of the building, its orientation and the position of the openings. Guidelines are set for the design and pre-dimensioning of ventilation devices. The rules are determined by a comparative analysis of nine contemporary ventilation projects in which the ventilation device is present. An optimized wind tunnel is created to simplify airflow visualizations around building models. We provide also a method to make simplified experimentations, an aiding-design tool, and a code that allows to understand the views with the smoke. We study the geothermal cooling system of an ancient villa in Costozza (Vicenza, Italy). This section extends the knowledge of the Italian architectural heritage and highlights the importance of rediscovering existing bioclimatic technology solutions, still in operation. An animal structure is analysed: the bug of an insect. This is a bioclimatic archetype and therefore it can be applied to architecture as a biomimetic technology

Multi-hop wireless networks or ad-hoc networks face several limiting characteristics that make it difficult to support a multitude of applications. It is in this context that we find smart antennas to find significant applications in these networks, owing to their ability to alleviate most of these limitations. The focus of my research is thus to investigate the use of smart antennas in ad-hoc networks and hence efficiently design network protocols that best leverage their capabilities in communication. There are two parts to the proposed objective of designing efficient network protocols that pertain to the nature of the smart antenna network considered, namely, homogeneous and heterogeneous smart antenna networks. Unlike heterogeneous smart antenna networks, where different devices in the network employ different antenna technologies, homogeneous smart antenna networks consist of devices employing the same antenna technology. Further, in homogeneous smart antenna networks, different antenna technologies operating in different strategies tend to perform the best in different network architectures, conditions and application requirements. This motivates the need for developing a {em unified} framework for designing efficient communication (medium access control and routing) protocols for homogeneous smart antenna networks in general. With the objective of designing such a unified framework, we start by designing efficient MAC and routing protocols for the most sophisticated of the smart antenna technologies, namely multiple-input multiple-output (MIMO) links. The capabilities of MIMO links form a super-set of those possible with other antenna technologies. Hence, the insights gained from the design of communication protocols for MIMO links are then used to develop unified MAC and routing frameworks for smart antennas in general. For heterogeneous smart antenna networks, we develop theoretical performance bounds by studying the impact of increasing degree of heterogeneity on network throughput performance. Given that the antenna technologies are already unified in the network, unified solutions are not required. However, we do develop efficient MAC and routing protocols to best leverage the available heterogeneous capabilities present in the network. We also design efficient cooperation strategies that will further help the communication protocols in exploiting the available heterogeneous capabilities in the network to the best possible extent.

Made available in DSpace on 2014-12-17T15:48:06Z (GMT). No. of bitstreams: 1 RicardoJSJ_DISSERT.pdf: 4102063 bytes, checksum: 92b62a467283fb011a1258e8b80ca7b4 (MD5) Previous issue date: 2013-02-01 / Checking the conformity between implementation and design rules in a system is an important activity to try to ensure that no degradation occurs between architectural patterns defined for the system and what is actually implemented in the source code. Especially in the case of systems which require a high level of reliability is important to define specific design rules for exceptional behavior. Such rules describe how exceptions should flow through the system by defining what elements are responsible for catching exceptions thrown by other system elements. However, current approaches to automatically check design rules do not provide suitable mechanisms to define and verify design rules related to the exception handling policy of applications. This paper proposes a practical approach to preserve the exceptional behavior of an application or family of applications, based on the definition and runtime automatic checking of design rules for exception handling of systems developed in Java or AspectJ. To support this approach was developed, in the context of this work, a tool called VITTAE (Verification and Information Tool to Analyze Exceptions) that extends the JUnit framework and allows automating test activities to exceptional design rules. We conducted a case study with the primary objective of evaluating the effectiveness of the proposed approach on a software product line. Besides this, an experiment was conducted that aimed to realize a comparative analysis between the proposed approach and an approach based on a tool called JUnitE, which also proposes to test the exception handling code using JUnit tests. The results showed how the exception handling design rules evolve along different versions of a system and that VITTAE can aid in the detection of defects in exception handling code / Verificar a conformidade entre a implementa??o de um sistema e suas regras de design ? uma atividade importante para tentar garantir que n?o ocorra a degrada??o entre os padr?es arquiteturais definidos para o sistema e o que realmente est? implementado no c?digo-fonte. Especialmente no caso de sistemas dos quais se exige um alto n?vel de confiabilidade ? importante definir regras de design (design rules) espec?ficas para o comportamento excepcional. Tais regras descrevem como as exce??es devem fluir atrav?s do sistema, definindo quais s?o os elementos respons?veis por capturar as exce??es lan?adas por outros elementos do sistema. Entretanto, as abordagens atuais para verificar automaticamente regras de design n?o proveem mecanismos adequados para definir e verificar regras de design espec?ficas para a pol?tica de tratamento de exce??es das aplica??es. Este trabalho prop?e uma abordagem pr?tica para preservar o comportamento excepcional de uma aplica??o ou fam?lia de aplica??es, baseada na defini??o e verifica??o autom?tica em tempo de execu??o de regras de design de tratamento de exce??o para sistemas desenvolvidos em Java ou AspectJ. Para apoiar esta abordagem foi desenvolvida, no contexto deste trabalho, uma ferramenta chamada VITTAE (Verification and Information Tool to Analyze Exceptions) que estende o framework JUnit e permite automatizar atividades do teste de regras de design excepcionais. Foi realizado um estudo de caso preliminar com o objetivo de avaliar a efic?cia da abordagem proposta sobre uma linha de produto de software. Al?m deste, foi realizado um experimento cujo objetivo foi realizar uma an?lise comparativa entre a abordagem proposta e uma abordagem baseada na ferramenta JUnitE, que tamb?m prop?e testar o c?digo de tratamento de exce??es utilizando testes JUnit. Os resultados mostraram que as regras de design excepcionais evoluem ao longo de diferentes vers?es de um sistema e que a VITTAE pode auxiliar na detec??o de defeitos no c?digo de tratamento de exce??o

The Diploma thesis is focused on marketing and semiotics and the use of these two fields combined. In the course of the thesis, we will deal with the analysis of single visual marketing modes and the overall impact on perception of the brand and also its ́ building by linking these elements. In the thesis, we will focus on the Gunter Kress ́ theory of multimodality and, in this context, we will focus on graphic design rules, which are reflected within each mode and which can deliver quality and consistent communication. Attention will be paid to semiotic analysis of colors, fonts, utilization of images and photos and other components important for creating a visual marketing strategy. In the empirical section, two similar brands will be introduced, on which the single modes will be demonstrated and analyzed. Although the two brands are similar to each other, one has a clearly recognizable brand identity, while the other brand is failing. By analyzing and comparing the visual content of these two brands, we will be able to detect errors that may be critical to brand building and may have a negative impact on the perception of the potential clients with the result of brand extinction. In the result of the thesis, we should be able to confirm the importance of using semiotic techniques in marketing...

La miniaturisation croissante des systèmes électroniques implique de réduire la taille des composants électroniques, en particulier des composants passifs (condensateurs, résistances et inductances), notamment les condensateurs, volumineux et de surcroît nombreux. Pour répondre à cette attente, une des options est d’intégrer « enterrer » les couches capacitives dans le circuit imprimé à base de matériaux composites céramique/polymère. Dans un premier temps, plusieurs types de matériaux composites à base de nanoparticules de céramique (BaTiO3 et BaSrTiO3) et de polyester pour des condensateurs enterrés sont développés. Ensuite, la permittivité ε’ et les pertes diélectriques des composites sont évaluées dans les gammes de fréquences entre [10 kHz – 10 MHz] et [1 GHz – 5 GHz]. En vue d’intégrer ces composants à l’intérieur du circuit imprimé parfois souple et flexible, le comportement piézoélectrique des composites est évalué. La mesure du courant de fuite permettant d’effectuer une analyse qualitative des matériaux composites a été également effectuée.Au niveau de l’étude des condensateurs enterrés dans le circuit imprimé, deux structures de tests ont été réalisées : l’une montée en parallèle et l’autre en série. L’étude est réalisée sur deux gammes de condensateurs. La première est à base de matériau composite stable en fréquence et la seconde varie avec la fréquence. Pour cela, une méthode originale qui permet d’extraire la variation de la permittivité εr (f) à haute fréquence a été développée. La méthode se repose principalement sur l’utilisation des résultats de mesure de la permittivité relative du condensateur en basse fréquence, et les résultats de la valeur de la fréquence de résonance obtenue en simulation électromagnétique.Enfin, pour améliorer la fréquence de fonctionnement des condensateurs enterrés, des règles de conception permettant de comprendre l’influence des vias de connexions et de la géométrie des électrodes sur la fréquence de résonance du dispositif de test sont étudiées. / The increasing miniaturization of electronic systems involves reducing the size of electronic components, in particular passive components (capacitors, resistors and inductors), including capacitors, large and many more. To meet this expectation, one of the options is to integrate "bury" the capacitive layers based on ceramic / polymer composites in the PCB. In a first step, several types of composite materials based on nanoparticle ceramic (BaTiO3 and BaSrTiO3) and polyester for buried capacitors are developed. Then, the permittivity ε' and the dielectric losses of the composites are measured in the ranges of frequencies between [10 kHz - 10 MHz] and [1 GHz - 5 GHz]. To integrate these components within the PCBs sometimes soft and flexible, the piezoelectric behavior of composites is evaluated. The measurement of leakage current to perform a qualitative analysis of composite materials was also made.At the level of the study of buried capacitors in the circuit board, two test structures were carried out: one mounted in parallel and the other in serial. The study is produced in two ranges of capacitors. The study is conducted on two capacitors ranges. The first case, the relative permittivity does not depend on the frequency while in the second case the frequency dependence is taken into account. For this, an original method which allows to extract the permittivity εr(f) variation in high-frequency was developed. The method is mainly based on the use of measurement results of the relative permittivity of low-frequency capacitor, and the results of resonance frequency value obtained by 3D HFSS electromagnetic simulation. Finally, to improve the operating frequency of the buried capacitors, design rules allowing understand the influence of the vias and geometry of electrodes on the resonant frequency of the structures are studied.

The steel bandage is an economical and effective widely used method for strengthening RC columns. Diploma thesis reviews most common design proposals for the types of the bandage with directly loaded and not directly loaded steel angles. This work also includes a comparison of the different constitutive laws for confined concrete. In order to simulate real behaviour of strengthened structure the numerical analysis has been carried out using non-linear software ATENA. According to the European standards and adopted hypotheses the simplified analytical model has been derived to be able to calculate load-bearing capacity of a strengthened column under normal force and bending moment. The proposed model considers the contribution in confinement pressure caused by steel bandage and the contribution of directly loaded angles. In addition, the direct application on real frame structure has been performed.