Modern architecture has lost its sense of place by the adoption of practices like standardization and universal modularity, over the focus and influence of unique local building practices. However, looking outside of the cultural main stream works of architecture, there exists some built structures with such purity around how they were constructed and a form of honesty deeply embedded within their material usage. Having been idealized in such a locally specific manner, these attributes become the essence of belonging that ties the building to its particular place. In this thesis, I have considered architecture both within regional or vernacular architectural traditions and the unconstrained means and methods of modern architecture. I looked at how modern technologies related to fabrication can be influenced by the subtle adaptations that traditional architecural crafts have developed, unique to specific regions. / Master of Architecture

No / This title provides a comprehensive and authoritative review on recent advancements in the application and use of composite scaffolds in tissue engineering. Chapters focus on specific tissue/organ (mostly on the structure and anatomy), the materials used for treatment, natural composite scaffolds, synthetic composite scaffolds, fabrication techniques, innovative materials and approaches for scaffolds preparation, host response to the scaffolds, challenges and future perspectives, and more. Bringing all the information together in one major reference, the authors systematically review and summarise recent research findings, thus providing an in-depth understanding of scaffold use in different body systems.

No / This title provides a comprehensive and authoritative review on recent advancements in the application and use of composite scaffolds in tissue engineering. Chapters focus on specific tissue/organ (mostly on the structure and anatomy), the materials used for treatment, natural composite scaffolds, synthetic composite scaffolds, fabrication techniques, innovative materials and approaches for scaffolds preparation, host response to the scaffolds, challenges and future perspectives, and more. Bringing all the information together in one major reference, the authors systematically review and summarise recent research findings, thus providing an in-depth understanding of scaffold use in different body systems.

Yes / Cementitious composites, the most abundant human-made materials in the world, are challenged to be more sustainable, durable and cost-effective to adapt to the development of structural engineering, economy and environment. Owing to their excellent strength, toughness and durability, nano-fillers reinforced cementitious materials have attracted broad attention in civil engineering researches and applications. However, it is worth noting that nano-fillers reinforced cementitious materials achieve their proprieties by using of different industrial nano-fillers, i.e., graphenes, carbon nanotubes, carbon nanofibers, etc. Although the properties of conventional cementitious materials are improved, the incorporation of the above nano-fillers are high cost and environmental footprint. Different from high-energy consuming carbon nanofillers, nanocellulose is one of the biomass-derived nanofillers with excellent nanometer properties, biological performances and composite effects, and it has proved to be a promising green filler to enhance the mechanical properties, durability and functional properties and lower the carbon footprint of cementitious composites. Therefore, this paper provides an overview on biomass-derived nanocellulose modified cementitious composites, mainly focusing on their fabrication, properties (early performance, mechanical performance, durability, and functional performance) and applications. It also concludes with an outline of some future opportunities and challenges in the development of biomass-derived nanocellulose modified cementitious composites.

Titre de l'écran-titre (visionné le 26 mars 2024) / La fabrication additive est une méthode de fabrication prisée pour la diminution de la consommation en matières premières et la capacité de fabriquer des pièces de géométries complexes. Or, la matière première couramment utilisée provient de l'atomisation au gaz ou de l'atomisation au plasma, ce qui engendre des coûts élevés. L'utilisation de poudres provenant de ces méthodes de fabrication est expliquée par l'obtention de particules sphériques contenant une faible concentration d'oxygène (< 0.05%-m.). L'atomisation à l'eau permettrait de diminuer les coûts de production des poudres. Toutefois, ces poudres seraient faites de particules de morphologie irrégulière et oxydées. Le principal objectif de notre étude est de quantifier la possibilité d'utiliser des poudres d'acier à outil produites par atomisation à l'eau dans un contexte de fabrication additive en lit de poudre. L'acier à outils A8 possède une haute ténacité, une bonne résistance à l'usure ainsi qu'une composition chimique intéressante pour limiter l'oxydation de la poudre lors de l'atomisation à l'eau. L'augmentation des propriétés rhéologiques ainsi que la diminution de la concentration d'oxygène des poudres sont réalisées lors de l'atomisation à l'eau et/ou lors de traitements secondaires effectués sur la poudre. Les traitements secondaires consistent en la sphéroïdisation au plasma, l'enlèvement de nanoparticules par nettoyage au bain ultrason et par frittage, l'addition de carbure de tungstène par sphéroïdisation au plasma et par frittage, le broyage ainsi que des traitements thermiques visant la réduction à l'oxygène. Les résultats de notre étude ont montré qu'il est possible d'utiliser des poudres atomisées à l'eau en fabrication additive par fusion laser sur lit de poudre. Qui plus est, cette approche permet d'obtenir des pièces, dont les propriétés mécaniques rivalisant avec celles de pièces fabriquées à l'aide de procédés de fabrication conventionnelle telles que le forgeage ou le laminage. La possibilité d'impression serait toutefois augmentée en diminuant la concentration en carbone. L'ajout de carbure de tungstène lors de la sphéroïdisation au plasma et par diffusion via le prémélange + frittage permet d'obtenir une microstructure contenant des carbures de grande taille qui ne pourrait être incorporés autrement à une pièce d'acier à outil A8. / Additive manufacturing is sought after due to its possibilities in raw material reduction and its capacity to manufacture complex geometries. Currently, feed material for AM comes principally from gas or plasma atomization. Powders obtained by these processes are made of spherical particles that are characterized by their low oxygen content (< 0.05% wt.). Nevertheless, gas and plasma atomization are significantly more expensive of powder production than water atomization. Development of metal powders for AM produced by water atomization could bring significant advantages related to powder production rate and therefore cost reduction for alloys of interest able to be produced by this process. A8 tool steel possess high toughness, good wear resistance and an interesting chemical composition to limit powder oxidation during water atomization. Improving powder properties for AM could be done during the water atomization process and/or with post treatment on powders. Post treatments explored in this study are plasma spheroidization, ultrasonic bath cleaning, tungsten carbides addition, milling and heat treatment for oxygen reduction and sintering. The main findings of our study shows that the fabrication of A8 tool steel components by laser powder bed fusion AM with water atomized powders is possible and yields good mechanical properties that are similar to those obtained with wrought components. Printing possibilities could be improved by limiting carbon concentration in steel. Tungsten carbide addition achieve microstructures with coarse carbides otherwise out of reach.

Thèse en cotutelle : Université Laval, Québec, Canada, Philosophiæ doctor (Ph. D.) et Université de Haute Alsace, Mulhouse, France / Le remplacement de la valve aortique par chirurgie non invasive TAVR est devenu une alternative au remplacement à cœur ouvert chez des patients à haut risque chirurgical. En 2018, plus de 300 000 patients à travers le monde ont reçu une valve aortique par voie transcathéter ce qui représente un marché mondial d'une valeur de 2 milliards de dollars par an. Cependant la durée de vie du tissu biologique utilisé pour réaliser les feuillets valvulaires dans les dispositifs existants reste une problématique à résoudre, car il existe très peu de données cliniques sur le sujet. En effet, l’implantation transcathéter impose des contraintes spécifiques, qui tendent à dégrader et fragiliser le matériau dont la durée de vie devient limitée. Le succès de la procédure TAVR favorise la recherche des matériaux synthétiques de remplacement valvulaires comme alternatives aux tissus biologiques, dont la durabilité reste inconnue. En particulier, la valve textile a récemment prouvé sa durabilité sur une étude In Vivo de 6 mois effectuée sur des moutons. La fibrose et la calcification restent cependant des facteurs critiques à contourner. Dans ce contexte, cette thèse s’inscrit dans la perspective de développer des stratégies pour améliorer labio compatibilité de la valve de substitution textile en polyéthylène téréphtalate PET. Dans le cadre de ce projet, deux stratégies ont été investiguées parallèlement pour limiter les problématiques de biocompatibilité de la valve textile. Premièrement, une fonctionnalisation de la valve textile au Polyéthylène glycol a été effectué pour augmenter son caractère hydrophile ce qui limiterait la fibrose. La valve est traitée en surface au plasma pour ne pas compromettre la flexibilité et les propriétés mécaniques du matériau textile. Une caractérisation du traitement ainsi que des études in vitro complétées par deux implantations in vivo ont été réalisées. Deuxièmement, un concept innovant de la valve hybride a été étudié. Ce concept consiste à élaborer un textile hybride composé d’un tissé de polytéréphtalathe d’éthylène (PET) auquel sera adjoint un textile non tissé de microfibres de PET afin de limiter la fibrose. Les caractéristiques physiques et les performances mécaniques de cette valve hybride ont été étudiées. Cette stratégie a été complétée par l’étude des intéractions du substrat de textile hybride avec les cellules. Des textiles hybrides de différents types ont été considérés pour démontrer l’influence de leurs propriétés physico-chimiques sur le comportement cellulaire. Cette étude vient confirmer le potentiel du concept de la valve hybride pour limiter le phénomène de fibrose Dans l’ensemble, ce projet de recherche a mis en évidence que ces deux stratégies ont bel et bien limité la fibrose mais ils ont révélé une problématique de calcification qui est critique dans la mesure où elle provoque la rigidification des feuillets de la valve. Plusieurs stratégies seront discutées pour limiter ce phénomène. / Over the last decade, transcatheter aortic valve replacement (TAVR) has become an accepted alternative technique to surgical valve replacement for over 300.000 patients worldwide in 2018, representing a global market worth-2 billion per year. This non-invasive technique provides increased comfort to the patient but is today mainly used for critical patients who cannot undergo classic surgery. Currently, the valve material used in the TAVR procedure is made of biologic tissues. However, there is a lack of data about the long-term durability of biological tissues used in transcatheter devices. Consequently, future devices should be manufactured with a smaller diameter in order to be more easily inserted through already diseased artery networks. Accordingly, it is of interest to investigate the potential of synthetic valve leaflet materials as an alternative to biological tissues. In particular, textile valves have recently proven durability in vivo over a 6 months period in animal sheep models. Exaggerated fibrotic tissue formation remains, however, a critical issue to be addressed. In this context, the aim of this work is to investigate strategies to improve the biocompatibility of the polyethylene terephthalate (PET) textile valve. As part of this project, two strategies were studied in order to limit the problems of biocompatibility of the textile valve. The first strategy consists on investigating the potential of PET textiles covalently conjugated with PEG to modulate the fibrosis formation both in vitro and in vivo. For this purpose, the surfaces of heart valves made of PET textiles were functionalized using an atmospheric pressure plasma in a gas environment enabling the formation of carboxylic acid (-COOH) groups on the surface of the material and further conjugated with PEGNH2. PEGylated surfaces were then characterized, and cell culture was carried out using rat cardiac fibroblast cells. In addition, an in vivo implantation of a PEG treated valve in a juvenile sheep model was performed and showed a significant fibrosis reduction. The implantation also revealed calcification issues that need to be addressed. The second strategy consists on investigating the design of a composite hybrid fibrous construction combining a woven PET layer and a non-woven PET mat, which are expected to provide respectively strength and appropriate topography towards limited fibrotic tissue ingrowth. For that purpose, a specific equipment has been developed to produce slight non-woven PET mats. These mats were assembled with woven PET substrates using various assembling techniques in order to obtain hybrid fibrous constructions. The physical and mechanical properties of the obtained materials were assessed and valve samples were manufactured to be tested in vitro for hydrodynamic performances. Then, a study of the interactions of the hybrid textile substrate with cells was conducted. Hybrid textiles of different types have been explored to demonstrate the influence of their physicochemical properties on cellular behavior. Results bring out that the composite hybrid fibrous construction is characterized by properties suitable for the valve leaflet function and for limiting the phenomenon of fibrosis, but the durability of the assembling is however limited under accelerated cyclic loading. Briefly, this research project revealed that these two strategies did indeed limit fibrosis, but that there is another problem of calcification that is critical as it stiffens the leaflets of the valve. Several strategies will be discussed to limit this phenomenon.

Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2016-2017 / Le fromage Mozzarella entre dans la composition de plusieurs mets populaires d’Amérique du Nord. L’aptitude de ce fromage à être râpé et ses propriétés caractéristiques de cuisson en font un ingrédient idéal. Ces qualités sont attribuées principalement aux propriétés physiques particulières de ce fromage sous certaines conditions de cisaillement et de température. Le but de ce projet était d’évaluer l’impact de différentes stratégies couramment mises en oeuvre dans l’industrie fromagère sur la composition, la microstructure et les propriétés physiques du fromage. Diverses stratégies ont été étudiées : les conditions de filage du caillé lors du procédé de « pasta filata », l’addition de protéines sériques dénaturées, le contrôle de la minéralisation et le vieillissement du fromage. Les résultats ont démontré que le contrôle de l’intensité mécanique et thermique fournie lors du filage permettait respectivement de réduire les pertes de solides et d’améliorer la répartition de la phase aqueuse dans la matrice fromagère. L’aptitude au râpage du fromage peut être optimisée en combinant l’utilisation de plusieurs stratégies dont la réduction du calcium colloïdal, un temps de vieillissement adéquat et un râpage à basse température. Par ailleurs, des changements aux facteurs mentionnés précédemment sont apportés lors de l’ajout de protéines sériques dénaturées, ces dernières ayant un impact sur la composition et la structure du fromage. Des modèles prédictifs de l’aptitude au râpage ont été développés en sélectionnant uniquement les descripteurs de composition et de texture pertinents. La perception sensorielle du fromage cuit sur pizza et les propriétés physiques du fromage fondu ont été considérablement influencées par l'évolution physico-chimique du fromage au cours du vieillissement. L’utilisation d’une nouvelle approche pour la caractérisation des propriétés rhéologiques du fromage fondu sous fortes contraintes a permis d’établir de bonnes relations avec les descripteurs sensoriels de texture. Ce travail a permis de valider l’hypothèse que l’utilisation d’une ou plusieurs stratégies simples et accessibles pouvait être mise de l’avant afin d’optimiser les propriétés physiques du fromage Mozzarella. Cela contribue à une meilleure compréhension des facteurs pouvant être contrôlés afin de développer des fromages avec des attributs spécifiques, lorsqu’utilisés comme ingrédient. / Mozzarella cheese is expected to perform various key attributes when used as a food ingredient. The shreddability and the melting properties of cheese during and after baking are mainly governed by the physical properties of cheese when subjected to external factors such as shear and temperature. Therefore, the goal of this project was to evaluate the impact of cheese-making strategies commonly used in the dairy processing industry on the cheese composition, microstructure, and physical properties. Various strategies were studied: pasta filata process conditions, addition of denatured whey protein (WP-D) to milk, control of curd mineralization, and cheese aging. Results showed that controlling the mechanical and thermal intensity during the pasta filata process can lead to reduced cheese solid losses and a better distribution of water within cheese microstructure, respectively. The ability of cheese to be shredded can be increased using a combination of multiple factors such as lowering colloidal calcium phosphate associated with casein, proper aging, and by reducing cheese temperature before shredding. However, an optimisation of the previous factors should be done if WP-D is added because of its impact on cheese composition and structure. Predictive models to assess cheese shreddability were built using only few relevant compositional and textural descriptors. Sensory perception of baked cheese texture and physical properties of melted cheese were dramatically influenced by the physico-chemical evolution of cheese during aging. Melted cheese texture was satisfactorily related to different sensory attributes using a novel approach to determine the rheological properties under the large stress experienced during mastication. This work validated the hypothesis that simple cheese-making strategies, alone or combined, can be used to optimize the cheese physical properties. This contributes to a better understanding of the factors that can be controlled to improve or develop cheese ingredient with specific attributes.

This thesis questions the coherence of modes of fabrication that introduce materials to a living context, in forms that resist the processes of biological change. In doing so this project explores the ideologies embedded in fabrication that have led to this current position. The implications of an accumulation of materials being recognized as an autonomous object, and treated as if they are detached from their environment are also expanded. The sculptural methodology used to undertake this investigation has used the feature of materiality and it’s behaviours, of both human fabrication and the living environment, as a means to explore processes outside the limitations of specialist human categories of knowledge. The vocabularies of dematerialization, expansion and relational exchange in the critique of sculpture, have provided a starting point to articulate what is implied or “mapped out but not socially recognized”1 by the structure of specialist categories. The practice-based work that has driven this project, documents an extension of sculptural fabrication, which incorporates the literal processes of growth and erosion, illustrating a radical inclusivity of all living phenomena. Engaging with fabrication through this plural and complex methodology allows for a new valuing that recognizes accumulation as a result of employing reductive specialist categories and as inherently problematic for complex living systems. This identifies coherent fabrication as that which merges its engagement with processes of biological change and utility for humans.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / As we adopt and implement the doctrines of reengineering, we at NASA/Jet Propulsion Laboratory (JPL) are asked to make a giant leap in how we think of and design SpaceCraft. We call what we are doing a revolution, since we are not “evolving” to the next step in our activity, but literally leaping beyond it. This is fully in concert with the concepts of reengineering, in that areas that need to be changed are indeed literally invented anew. To be successful, JPL and its industry partners, must perfect processes, techniques and methods that allow them to work together at all levels of the SpaceCraft development cycle. If all other parts of the discipline have moved on and changed, but a key portion remains locked in a time warp of yesterday, we will not be able to reach our desired goal. At the present time change is occurring all over JPL, and it is our intent to describe how it applies to areas where prototype, or one of a kind hardware are fabricated, and how these areas might look when new approaches to doing business are applied. Since all activities in an organization must attain similar levels of expertise or be in danger of hampering the entire process, the issues of Packaging Engineering, Manufactureability, and fabrication become key items.

L'Organisation des Nations Unies vise à moderniser les industries afin de les rendre durables et plus respectueuse de l'environnement d'ici 2030. Afin de répondre à ces attentes, il faut mettre en place des voies d'améliorations des procédés de fabrication d'un point de vue environnemental. Cette démarche nécessite une connaissance fine des flux entrants et sortants lors de la fabrication d'un produit. Néanmoins, ce n'est pas le cas pour les procédés de fabrication additives ou les impacts environnementaux générés lors de la fabrication d'un produit sont encore méconnus. Par conséquent, il est primordial de bien "compter" les différentes sources de consommations et de rejets. Pour cela, une évaluation quantitative des flux intervenants pendant la fabrication de pièces est nécessaire pour améliorer la connaissance de la performance environnementale d'un procédé. Les travaux de cette thèse portent sur la proposition d'une méthodologie d'évaluation multicritère pour les procédés de fabrication additive afin de pouvoir prédire, dès l'étape de conception d'un produit, des informations sur les aspects techniques, économiques et environnementaux du couple pièce/procédé. Afin de proposer aux concepteurs la possibilité d'évaluer un produit dès son étape de conception, des modèles de consommation fins traduisant le comportement du procédé ont été mis en place. La méthodologie développée s’intéresse à l'ensemble des sources de consommation et de rejets ainsi qu'à l'ensemble des étapes nécessaires à la fabrication d'une pièce mécanique.Ce manuscrit est divisé en six chapitres qui permettent de présenter le contexte général de l'étude, l'état de l'art, la méthodologie d'évaluation multicritère, l'application sur les procédés de fabrication additive et l'exploitation sur un cas industriel. Le dernier chapitre se consacre à la conclusion sur les apports de ces travaux et propose des perspectives de recherche. / The United Nations aims to modernize industries in order to make them sustainable and more environmentally friendly by 2030. In order to meet these expectation, it is necessary to put in place ways of improving production processes from an environmental point of view. This approach requires a detailed knowledge of the incoming and outgoing flows during the manufacturing of a product. However, this is not the case for additive manufacturing processes where the environmental impacts generated during this stage are still unknown. For that, a quantitative evaluation of the flows involved during the manufaturing of parts is necessary in order to improve the knowledge of the environmental performance of a process. The work of this thesis focuses on the development of methodology for additive manufacturing processes in order to predict information on the technical, economic, and environmental aspects of a product during the design stage of a part. The methodology developped is increasingly interested in all the sources of consumption as well as all the stages necessary for the manufacturing of a mechanical part.This manuscript is divided into six chapters that can present the general context of the study, the state of the art, the methodology developped, a application of the methodology to additive manufacturing processes and the computer tool developed during this thesis. The last chapter is devoted to the conclusion on the contributions of this work and provides research perspectives.