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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

[pt] FLUXO DE INFORMAÇÃO (IDM) CONSIDERANDO O CÁLCULO DA ENERGIA E CARBONO EMBUTIDO PARA REUSO DE AÇO ESTRUTURAL / [en] INFORMATION DELIVERY MANUAL CONSIDERING INCORPORATED CARBON AND ENERGY CALCULATION FOR STRUCTURAL STEEL REUSE.

CATARINA CAMPELO DE MENDONCA 06 May 2020 (has links)
[pt] A necessidade de diminuir os impactos ambientais provenientes da indústria da construção civil estimulou a criação de acordos governamentais ao redor do mundo, métricas quantitativas de impactos ambientais, novos materiais e novas técnicas e conceitos para o desenvolvimento de projetos sustentáveis. A reutilização de materiais com alto índice de energia incorporada, como os elementos estruturais de aço, é considerada uma prática válida para atingir este objetivo, sendo mais sustentável do que a reciclagem do aço em termos de emissão de dióxido de carbono, energia incorporada, processamentos e, em alguns casos, transporte. O projeto para desmontar é um conceito aliado à prática de reutilização de aço estrutural e dos demais materiais de construção, promovendo o planejamento de desmontes futuros e contribuição da cadeia de suprimentos com materiais para reutilização. Além disso, o BIM fornece um ambiente promissor para a troca de informações durante todo o ciclo de vida da construção, assim como um novo fluxo de trabalho e informações na fase de concepção de projetos que promove melhorias nas tomadas de decisão no contexto de construções sustentáveis. Este trabalho propõe uma nova dinâmica de troca de informações através de um IDM (Information Delivery Manual) da concepção de um projeto com baixos índices de impactos ambientais a partir da Avaliação do Ciclo de Vida e reutilização de materiais. A Avaliação do Ciclo de Vida de cenários de uma edificação foi utilizado para desenvolver as tarefas propostas pelo IDM. Os resultados obtidos pelos experimentos indicam que o desenvolvimento de um projeto sustentável não interfere significativamente com os interesses econômicos, práticos, estéticos e que a inclusão da Avaliação do Ciclo de Vida é um fator importante nas tomadas de decisões na fase de projeto para melhorar o desempenho ambiental dos materiais utilizados. / [en] The necessity to reduce environmental impacts caused by construction industry promoted the creation of several government agreements around the world, quantitative measures of environmental impacts, new materials and new techniques and concepts for sustainable projects. Reusing materials with a high index of embodied energy, such as structural steel elements, is considered a valid practice to achieve this objective. Steel reuse is more sustainable than recycling in terms of carbon dioxide emissions, embodied energy, processing and, in some cases, transportation. The DfD (Design for Disassembly) is a concept allied to the practice of structural steel reuse and other building materials, planning future disassembly and contributing to the supply chain with reusable materials. Moreover, BIM provides a promising environment for the exchange of information throughout the buildings life cycle, as well as a new workflow in the conceptual design phase, which improves the decision making process in the context of sustainable constructions. This work proposes a new dynamic in terms of information exchange through an IDM (Information Delivery Manual) for developing a project with low levels of environmental impact using LCA (Life Cycle Assessment) and material reuse. A building s LCA study was used to develop the analysis and interpretation of environmental impact of projects conceived using the proposed IDM. The results indicate that the development of a sustainable project does not significantly interfere with the economic, practical and aesthetic interests and that including LCA is an important parameter in decision-making at the design stage to improve the environmental performance of the materials used.
112

p63 regulates Satb1 to control tissue-specific chromatin remodeling during development of the epidermis

Fessing, Michael Y., Mardaryev, Andrei N., Gdula, Michal R., Sharov, A.A., Sharova, T.Y., Rapisarda, Valentina, Gordon, K.B., Smorodchenko, A.D., Poterlowicz, Krzysztof, Ferone, G., Kohwi, Y., Missero, C., Kohwi-Shigematsu, T., Botchkarev, Vladimir A. January 2011 (has links)
No / During development, multipotent progenitor cells establish tissue-specific programs of gene expression. In this paper, we show that p63 transcription factor, a master regulator of epidermal morphogenesis, executes its function in part by directly regulating expression of the genome organizer Satb1 in progenitor cells. p63 binds to a proximal regulatory region of the Satb1 gene, and p63 ablation results in marked reduction in the Satb1 expression levels in the epidermis. Satb1(-/-) mice show impaired epidermal morphology. In Satb1-null epidermis, chromatin architecture of the epidermal differentiation complex locus containing genes associated with epidermal differentiation is altered primarily at its central domain, where Satb1 binding was confirmed by chromatin immunoprecipitation-on-chip analysis. Furthermore, genes within this domain fail to be properly activated upon terminal differentiation. Satb1 expression in p63(+/-) skin explants treated with p63 small interfering ribonucleic acid partially restored the epidermal phenotype of p63-deficient mice. These data provide a novel mechanism by which Satb1, a direct downstream target of p63, contributes in epidermal morphogenesis via establishing tissue-specific chromatin organization and gene expression in epidermal progenitor cells.
113

Designing supplementary space in multi-family housing

Moshaver, Sam 08 1900 (has links)
La démographie et les modes de vie ont considérablement évolué au cours des dernières décades. De tels changements sont destinés à influencer la conception de l’habitation et ils incluent notamment une série de besoins émergents: s’en suivent des besoins additionnels en espace pour répondre à l’arrivée de ces activités additionnelles au niveau du logement. La planification en vue de répondre à ces besoins émergeants constitue le principal thème de la présente thèse. Dans le cas de la maison unifamiliale détachée, le sous-sol est disponible pour offrir des espaces appropriés à ces besoins émergents. Par contre, une telle ressource n’est normalement pas présente dans le cas d’un édifice multifamilial. La thèse propose un espace additionnel spécifique en vue de répondre à ces besoins émergents : l’espace supplétif. Même si un tel espace n’est pas envisagé dans les publications du domaine, des précédents existent quant à sa présence en planification multifamiliale. Le but de la présente étude est d’offrir des lignes directrices quant à la conception et l’intégration d’un tel espace supplétif. Elle va s’appuyer sur l’approche systémique en raison de la logique de déduire la solution à partir d’une analyse de l’objectif. L’application de l’approche systémique implique donc que tous les critères correspondant à la nature spécifique de l’espace supplétif seront extrapolés à partir de l’objectif. Dans le cas la présente étude, ce sont les critères du bureau à domicile qui seront d’abord précisés car il s’agit de l’activité émergente la plus exigeante. Les critères seront traités comme vecteurs d’un modèle générique indicatif de la manière d’organiser l’espace supplétif. Ce modèle visera le bureau à domicile en vue d’offrir les solutions pertinentes et il se concentrera principalement sur les critères d’intimité visuelle et spatiale. La contribution du modèle sera de suggérer des lignes directrices en vue d’incorporer l’espace supplétif à l’intérieur des édifices résidentiels de type multifamilial, ce que la planification conventionnelle n’offre pas. C’est le concept d’adaptabilité qui est à la base de toute stratégie visant à permettre le changement en architecture et en habitation, d’autant plus lorsqu’il s’agit d’un espace supplétif. À cet effet, l’espace supplétif va recourir à l’approche Open Building afin d’appliquer le concept d’adaptabilité, en raison de ses avantages majeurs tant au niveau conceptuel que constructif. Différentes applications de l’approche Open Building, telles que le projet NEXT21 et le protocole KSI (Kikou support and Infill), offrent des exemples susceptibles de constituer d’efficaces lignes directrices pour la conception d’un espace supplétif. La faisabilité du modèle d’espace supplétif proposé est vérifiable et démontrable dans le monde réel. Les systèmes constructifs industrialisés sont en mesure de permettre le changement sans démolition car leurs joints mécaniques « à sec » rencontrent généralement les normes DfD (Design for Disassembly), non seulement en ce qui concerne l’espace supplétif mais pour l’ensemble du logement. / Demographics and lifestyles have changed considerably in the past few decades. These changes are bound to influence the design of housing and they notably include a series of emerging needs: additional spatial needs due to additional activities brought to the traditional housing premises. Planning for those emerging needs is the main theme of this thesis. In a typical single-family detached house, the basement is available to accommodate the spatial requirements for these emerging needs. However, such a provision does not typically exist in multi-family housing. This thesis proposes a specific additional space to accommodate these emerging needs: the supplementary space. Although such a space has not been explored in the literature, there are precedents for its application in multi-family floor planning. The objective of this study is to provide guidelines for the design and the integration of this supplementary space. It relies on the systems approach as the design-decision methodology due to its logic of deducting the solution from the analysis of the objective. Applying the systems approach means that all the criteria corresponding to the specific purpose of the supplementary space will be extrapolated from the objective. However, once the supplementary space is being used to deal with emerging needs, it will then introduce its own relevant criteria. This study will start with the criteria for designing a home office because this is the most demanding emerging needs activity. The criteria are organized as vectors of a generic model indicating how the supplementary space can be formulated. The model will target the workplace at home and subsequently offer solutions to them. This study focuses on the planning provisions dealing mainly with visual and spatial privacy. The overall outcome of the model is to suggest guidelines to incorporate the supplementary space within multi-family residential buildings, a feature not offered in traditional planning. The concept of adaptability is the key design strategy to accommodate change in architecture and housing, even more in the case of a supplementary space. Therefore, the supplementary space model will apply the concept of adaptability through the Open Building (OB) approach; elaborating more on the practical design and construction features. Different OB applications, such as the NEXT21 project and the KSI (Kikou Support and Infill) protocol in Japan, are examples that can be used as efficient guidelines to design a supplementary space. The feasibility of the supplementary space model can be validated and served in the real world. Industrialized building systems are capable of accommodating change without demolition as their dry mechanical joints are generally at meeting the DfD (design for disassembly) standards, not only for the supplementary space but also for the whole dwelling unit.
114

Kreislaufwirtschaft nach dem Cradle-to-Cradle-Vorbild: Wie kann ein geschlossener Ressourcenkreislauf erreicht werden?: Eine Untersuchung unternehmerischer Konzepte mit Beispielen aus der Praxis

Röhr, Tobias 03 February 2021 (has links)
Das aktuell vorherrschende lineare Wirtschaftsprinzip ist für viele Umweltprobleme verantwortlich. Neben der immensen Umweltverschmutzung sorgt der stetig wachsende Ressourcenverbrauch für eine zunehmende Verknappung vieler wertvoller Rohstoffe. Ein intelligentes Kreislaufwirtschaftskonzept wie Cradle-to-Cradle kann diesen Problemen entgegenwirken. Für eine erfolgreiche Umsetzung von Cradle-to-Cradle werden unternehmerische Ansätze benötigt. Im Rahmen dieses Artikels werden vier Konzepte untersucht, die in einer Kreislaufwirtschaft implementiert werden können. Diese sind Design für Demontage, Produkt-Service-Systeme, Take-back Strategien und Reverse Logistics. Für jeden dieser vier Ansätze werden die Voraussetzungen sowie Barrieren hinsichtlich der Umsetzung innerhalb eines Kreislaufwirtschaftssystems aufgezeigt. Zudem wird dargelegt, dass sie im Cradle-to-Cradle-System realisierbar sind. Weiterhin werden reale Beispiele in Form von Unternehmen vorgestellt, die die verschiedenen Modelle bereits erfolgreich umgesetzt haben. Alle vier untersuchten Konzepte sind für ein Kreislaufwirtschaftssystem unter Beachtung der Cradle-to-Cradle-Kriterien geeignet. / The currently prevailing linear economic principle is responsible for many environmental problems. In addition to the immense environmental pollution, the constantly growing consumption of resources is causing an increasing shortage of many valuable raw materials. An intelligent circular economy concept such as Cradle to Cradle can counteract these problems. Entrepreneurial approaches are needed for a successful implementation of Cradle to Cradle. This article examines four concepts that can be implemented in a circular economy. These are design for disassembly, product service systems, take-back strategies, and reverse logistics. For each of these four approaches, the prerequisites as well as barriers regarding the implementation within a circular economy system are shown. In addition, it is shown that they can be implemented in a cradle-to-cradle system. Furthermore, real examples are presented as companies that have already successfully implemented the various models. All four concepts examined are suitable for a circular economy system in compliance with the Cradle to Cradle criteria.
115

Augmented Reality-Assisted Techniques for Sustainable Lithium-Ion EV Battery Dismantling / Förstärkt Verklighet-Assisterade Teknikers för Hållbar Demontering av Litiumjonbatterier

Cristina Culincu, Diana January 2023 (has links)
The increasing adoption of electric vehicles (EVs) brings forth the challenge of effectively managing the second-life and end-of-life cycles for lithium-ion batteries. Augmented Reality (AR) offers a promising solution to sustainably and efficiently dismantle these batteries. This thesis explores the development and evaluation of an AR mobile app specifically designed for guiding the dismantling process of a Volkswagen (VW) ID.4 lithium-ion EV battery. Subsequently, a detailed end-to-end development pipeline is presented, spanning from identifying the correct dismantling steps and building complete 3D reconstructions of the ID.4 battery using photogrammetry and CAD or 3D modelling, to creating an AR mobile application in Unity with the help of Vuforia allowing users to visualize the disassembly steps through an interactive guide. Tracking recognition testing results for each model indicates that simpler models exhibit a higher chance of producing false positives, while composite models have a greater minimum recognition distance compared to the faithfulto-real-life one-piece counterparts. User testing is conducted using a hybrid approach, combining a Figma prototype with video recordings to replicate the app’s behavior in a safe environment, without the physical presence of a high voltage battery. Results show positive user feedback, demonstrating the app’s usability and effectiveness in guiding the dismantling process. Furthermore, the thesis evaluates the app’s performance through the System Usability Scale (SUS) and the Technology Acceptance Model. The obtained SUS score of 80 (Grade B - Good) indicates favorable usability, while the Technology Acceptance Model provides insights into potential users’ perceptions. / Den ökande användningen av elektriska fordon (EV) frambringar utmaningen att effektivt hantera andra livscykler och slutlivscykler för litiumjonbatterier. För att hållbart och effektivt demontera dessa batterier erbjuder Augmented Reality (AR) en lovande lösning. Denna uppsats utforskar utvecklingen och utvärderingen av en AR-mobilapplikation som specifikt är utformad för att guida demonteringsprocessen av ett Volkswagen (VW) ID.4 litiumjon EVbatteri. Därefter presenteras en detaljerad genomgående utvecklingsprocess, som sträcker sig från att identifiera korrekta demonteringssteg och skapa kompletta 3D-rekonstruktioner av ID.4-batteriet med hjälp av fotogrammetri och CAD eller 3D-modellering, till att skapa en AR-mobilapplikation i Unity med hjälp av Vuforia, som tillåter användare att visualisera demonteringsstegen genom en interaktiv guide. Resultaten bättre identifieringstester för varje modell indikerar att enklare modeller har större chans att producera falska positiva resultat, medan komplexa modeller har större minsta igenkänningsavstånd jämfört med helhetsmodeller som är trogna verkligheten. Användartester genomförs med hjälp av en hybridmetod som kombinerar en Figma-prototyp med videoinspelningar för att återskapa appens beteende i en säker miljö, utan att behöva ha ett högspänningsbatteri fysiskt närvarande. Resultaten visar positivt användarfeedback och bekräftar appens användarvänlighet och effektivitet vid guidning av demonteringsprocessen. Uppsatsen utvärderar också appens prestanda genom System Usability Scale (SUS) och Technology Acceptance Model. Den erhållna SUS-poängen på 80 (Betyg B - Bra) indikerar en god användbarhet, medan Technology Acceptance Model ger insikter om potentiella användares uppfattningar.
116

Screw Hole Detection in Industrial Products using Neural Network based Object Detection and Image Segmentation : A Study Providing Ideas for Future Industrial Applications / Skruvhålsdetektering på Industriella Produkter med hjälp av Neurala Nätverksbaserade Objektdetektering och Bildsegmentering : En Studie som Erbjuder Ideér för Framtida Industriella Applikationer

Melki, Jakob January 2022 (has links)
This project is about screw hole detection using neural networks for automated assembly and disassembly. In a lot of industrial companies, such as Ericsson AB, there are products such as radio units or filters that have a lot of screw holes. Thus, the assembly and disassemble process is very time consuming and demanding for a human to assemble and disassemble the products. The problem statement in this project is to investigate the performance of neural networks within object detection and semantic segmentation to detect screw holes in industrial products. Different industrial models were created and synthetic data was generated in Blender. Two types of experiments were done, the first one compared an object detection algorithm (Faster R-CNN) with a semantic segmentation algorithm (SegNet) to see which area is most suitable for hole detection. The results showed that semantic segmentation outperforms object detection when it comes to detect multiple small holes. The second experiment was to further investigate about semantic segmentation algorithms by adding U-Net, PSPNet and LinkNet into the comparison. The networks U-Net and LinkNet were the most successful ones and achieved a Mean Intersection over Union (MIoU) of around 0.9, which shows that they have potential for further development. Thus, conclusions draw in this project are that segmentation algorithms are more suitable for hole detection than object detection algorithms. Furthermore, it shows that there is potential in neural networks within semantic segmentation to detect screw holes because of the results of U-Net and LinkNet. Future work that one can do is to create more advanced product models, investigate other segmentation networks and hyperparameter tuning. / Det här projektet handlar om skruvhålsdetektering genom att använda neurala nätverk för automatiserad montering och demontering. I många industriföretag, såsom Ericsson AB, finns det många produkter som radioenheter eller filter som har många skruvhål. Därmed, är monterings - och demonteringsprocessen väldigt tidsfördröjande och krävande för en människa att montera och demontera produkterna. Problemformuleringen i detta projekt är att undersöka prestationen av olika neurala nätverk inom objekt detektering och semantisk segmentering för skurvhålsdetektering på indutriella produkter. Olika indutriella modeller var skapade och syntetisk data var genererat i Blender. Två typer av experiment gjordes, den första jämförde en objekt detekterings algoritm (Faster R-CNN) med en semantisk segmenterigs algoritm för att vilket område som är mest lämplig för hål detektering. Resultaten visade att semantisk segmentering utpresterar objekt detektering när det kommer till att detektera flera små hål. Det andra experimentet handlade om att vidare undersöka semantiska segmenterings algoritmer genom att addera U-Net, PSPNet och LinkNet till jämförelsen. Nätverken U-Net och PSPNet var de mest framgångsrika och uppnåde en Mean Intersection over Union (MIoU) på cirka 0.9, vilket visar på att de har potential för vidare utveckling. Slutsatserna inom detta projekt är att semantisk segmentering är mer lämplig för hål detektering än objekt detektering. Dessutom, visade sig att det finns potential i neurala nätverk inom semantisk segmentering för att detejtera skruvhål på grund av resultaten av U-Net och LinkNet. Framtida arbete som man kan göra är att skapa flera avancerade produkt modeller, undersöka andra segmenterisk nätverk och hyperparameter tuning.
117

The Skåne Sofa / Skånesoffan

Salonen Ripa, Beata January 2024 (has links)
As a counterpoint to globalisation, I wanted to see how locally a sofa can be produced and investi- gate how outsourcing affects Swedish production. The project is set in the Swedish region Skåne and shaped around three themes: locality, the consumer’s relationship to the product and ”design for disassembly”. The result is a deconstructable sofa made of Skåne wool, pine from the local lumber- man and linen from the last active weavery in Skåne. In this thesis I elaborate on the friction between profit-making, sustainability and consumerism and try to find answers to what production should look like in the future. / Som en motpol till globaliseringen ville jag se hur lokalt en soffa kan produceras och undersöka hur outsourcing påverkar svensk produktion. Projektet ugår ifrån Skåne och formades efter tre teman: lokalitet, konsumentens relation till möbeln och “design for disassembly". Resultatet är en isärtagbar soffa av skånsk ull, furu från bygdens sågverk och linne från det sista väveriet i Skåne. I min uppsats resonerar jag vidare kring friktionen mellan vinstintresse, hållbarhet samt konsumtionsbehov, och försöker hitta svar på hur framtidens produktion bör se ut.
118

<b>Sustainability Analysis of Critical Materials in Electric Vehicles with Emphasis on Circular Economy Principles</b>

Thomas Maani (19207021) 27 July 2024 (has links)
<p dir="ltr"><a href="" target="_blank">The electrification of the transportation sector is pivotal in reducing greenhouse gas emissions and decreasing dependence on fossil fuels. Central to this transition are battery electric vehicles (BEVs) and other clean energy technologies, which rely heavily on critical materials (CMs) such as cobalt, lithium, neodymium, and nickel. </a>These materials are essential for the performance of batteries, advanced electronics, and other components in BEVs. <a href="" target="_blank">However, the limited availability of these CMs poses potential constraints on the widespread adoption of such technologies.</a></p><p dir="ltr">This research delves into the implications of widespread BEV adoption on the demand for CMs in the United States, with a focus on both light-duty vehicles (LDVs) and medium- and heavy-duty vehicles (MHDVs). Various market penetration scenarios were analyzed, revealing that while MHDVs require more CMs per vehicle, the sheer volume of LDV sales drives the overall CM demand, particularly in a scenario with 100% BEV adoption. Key findings highlight that cobalt, graphite, lithium, neodymium, and nickel are critical for BEVs, whereas palladium and rhodium are more crucial for internal combustion engine vehicles (ICEVs). Also explored is the impact of lightweighting on LDVs, revealing that while substituting steel with aluminum increases the total CM quantity per vehicle, it reduces the vehicle's mass, operational energy consumption, and the demand for high-concern battery-related CMs. Additionally, changing the battery cathode chemistry from NMC622 to LFP significantly reduces CM use but increases the demand for strategic materials like copper and phosphorus due to the lower energy density of LFP-based batteries.</p><p dir="ltr">The research also highlights the importance of rare earth permanent magnets (REPMs), <a href="" target="_blank">particularly Neodymium-Iron-Boron (NdFeB) magnets, in clean energy technologies such as electric vehicles and wind turbines.</a> Neodymium, a critical material, faces supply chain risks. To lessen these risks, circular economy strategies have been proposed, including the recovery of needed materials from end-of-life (EoL) products. <a href="" target="_blank">A dynamic material flow analysis (MFA) model was developed to forecast such EoL flows for products containing REPMs and assess the recoverable neodymium from these EoL products. </a>The results indicate that even a modest recycling efficiency of 15% could meet 12% of the Nd demand for EVs by 2050, with reuse meeting up to 70% of the demand.</p><p dir="ltr">With the dynamic MFA model showing that circular economy principles could meet up to 70% of future neodymium demand in 2050, the next step was to investigate the techno-economic feasibility of recycling REPMs. A techno-economic assessment model was developed for establishing a magnet-to-magnet recycling facility for REPMs. Results revealed a net present value (NPV) of $8,867,111 over 20 years, a payback period of 3 years, and an internal rate of return (IRR) of 53%, providing a compelling case for investment in recycling infrastructure. Sensitivity analyses point to the selling price of recycled magnets, feedstock purchase price, facility throughput, and labor costs as the most influential factors on profitability.</p><p dir="ltr"><a href="" target="_blank">Additionally, this research explored the challenges and opportunities in the disassembly and recycling of EoL EV components, particularly traction motors containing REPMs. The complexity of disassembly, driven by varying component sizes and designs, is identified as a significant barrier. By evaluating manual disassembly times and proposing potential automation solutions, the study aims to streamline the disassembly process, thus facilitating more efficient recycling and remanufacturing operations.</a></p><p dir="ltr">The key contributions of this research are summarized as follows:</p><p dir="ltr">· Evaluated the vehicle CM demand of ICEVs and BEVs for LDVs and MHDVs and explored the impact of lightweighting and changing the battery cathode chemistry from NMC622 to LFP on CM demands.</p><p dir="ltr">· Developed a dynamic material flow analysis (MFA) model to forecast end-of-life (EoL) flows of products containing REPMs and assess the recoverable neodymium from these EoL products.</p><p dir="ltr">· Developed a techno-economic assessment (TEA) model to evaluate the viability of a magnet-to-magnet recycling facility.</p><p dir="ltr">· Performed disassembly analysis to assess the ease with which EoL BEV transmissions can be disassembled with a specific focus on the retrieval of traction motors (which house the REPMs) for potential reuse or remanufacturing.</p>
119

<b>OPTIMIZATION STRATEGIES OF A PARAMETRIC PRODUCT DESIGN </b><b>FOR A CIRCULAR ECONOMY WITH APPLICATION TO AN </b><b>ELECTRIC TRACTION MOTOR</b>

Jesús Pérez-Cardona (17501118) 01 December 2023 (has links)
<p dir="ltr">In our daily lives, we rely on a multitude of discrete products to meet our needs. Traditional product design approaches have primarily focused on economic and technical aspects, often overlooking the pressing environmental and social challenges facing society. Recognizing the limitations of our ecological systems to cope with the waste generated by our current industrial processes, there is a growing need to anticipate the potential consequences of product design across technical, economic, environmental, and social dimensions to pave the way for a sustainable future. One promising strategy within this context is the integration of sustainability principles into optimization-based design models that consider a product's entire life cycle. While there have been previous efforts to optimize product life cycles, a comprehensive exploration of optimization-based design methods with a focus on multiple objectives for discrete products is essential. This dissertation explores the integration of sustainability principles with optimization-based design by taking the electric traction motor used in electric vehicles as a case study. This complex and environmentally significant technology is ideal for investigating the tradeoffs and benefits of incorporating sustainability objectives into the design process.</p><p dir="ltr">The key tasks undertaken in this study are as follows:</p><ul><li>Development of a parametric design and optimization framework for a surface-mounted permanent magnet synchronous motor. In this task, a special emphasis is placed on reducing reliance on materials with a high supply risk, such as rare earth elements.</li><li>Creation of a parametric life cycle assessment model that combines life cycle assessment and optimization-based design to minimize a single-score environmental impact. This model offers insights into the environmental performance of product design and underscores the importance of minimizing environmental impact throughout a product's life cycle.</li><li>Integration of a life cycle costing model, incorporating techno-economic assessment and total cost of ownership perspectives, into the parametric life cycle assessment and optimization-based design models. This model is used to minimize levelized production and driving costs, shedding light on the trade-offs within this family of cost metrics and the optimization of manufacturing systems for motor production.</li><li>Proposal of a circular economy model/algorithm to assess the advantages of integrating the circular economy paradigm during the early design phase. All the mentioned objective functions are considered to study the impacts of applying the circular economy paradigm.</li></ul><p dir="ltr">The contributions of this research can be summarized as follows:</p><ul><li>Utilized a diverse array of analytical methodologies to parameterize the design process of a motor, incorporating the integration of Life Cycle Assessment (LCA) and Techno-Economic Analysis (TEA) models, as well as the incorporation of disassembly planning for informed decision-making in the early stages of design.</li><li>Proposed a generalized objective function denoted as the Supply Risk-equivalent (SR-eq.), aimed at mitigating the risks associated with the dependency on critical materials in product manufacturing.</li><li>Introduced a novel approach for visualizing non-dominated solutions within a multi-objective framework, with experimentation conducted on up to six distinct objectives.</li><li>Substantiated the significance of decarbonizing the electric grid while maintaining competitive cost structures, the importance of advancing non-destructive evaluation (NDE) procedures for assessing the condition of end-of-life (EoL) subassemblies, and optimizing the collection rate of EoL motors.</li></ul><p dir="ltr">Demonstrated that the optimization of technical metrics as surrogate indicators for economic and environmental performance does not necessarily yield designs that are concurrently optimal in economic and environmental terms.</p>

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