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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.
211

[en] DESIGN AND SOCIAL INNOVATION: SOCIAL TECHNOLOGY BASED ON METHODOLOGICAL APPROACHES TO DESIGN / [pt] DESIGN E INOVAÇÃO SOCIAL: TECNOLOGIA SOCIAL A PARTIR DE ABORDAGENS METODOLÓGICAS DO DESIGN

LUIZ CLAUDIO LAGARES IZIDIO 11 March 2021 (has links)
[pt] A presente dissertação trata do design como estratégia de inovação social, através do entendimento do uso de suas metodologias para o desenvolvimento de tecnologias sociais. Investiga como metodologias de design, usadas na prática de projetos/ grupos produtivos/ empreendimentos solidários com produção artesanal se tornam tecnologias sociais, e podem ser reaplicadas. Para tanto, foram realizadas revisões bibliográfica sobre conceitos de inovação social, tecnologia apropriada, prática colaborativa, tecnologia social, sustentabilidade e codesign, dentre outros; um levantamento dos princípios e parâmetros de formação de tecnologias sociais; um estudo de casos múltiplos com análise de quatro grupos que trabalham a relação do design com o artesanato, incluindo como instrumentos de pesquisa questionário online e entrevistas, mapeamento de iniciativas, análise dos dados com cruzamento de informações. Uma discussão acerca dos modelos metodológicos adotados pelas iniciativas dos quatro grupos se segue, e quadros comparativos são elaborados no intuito de dar visibilidade aos achados da pesquisa. O estudo verificou que no processo de inovação social o design contribui com suas metodologias, dentre outras coisas, para a geração de tecnologias sociais visando uma melhor qualidade de vida das pessoas, desenvolvimento local e transformação social. / [en] The present dissertation deals with design as a strategy of social innovation, through the understanding of the use of its methodologies for the development of social technologies. It investigates how design methodologies, used in the practice of projects / productive groups / solidary enterprises with handcraft production become social technologies, and can be reapplied. For that, a bibliographic review was carried out on concepts such as social innovation, appropriate technology, collaborative practice, social technology, sustainability and codesign, among others; a survey of principles and parameters of social technology formation was done; and a multiple case studies was conducted, with analysis of four groups working the relationship between design and the handcraft, including research instruments as online questionnaire and interviews, mapping initiatives, and data analysis with cross-information. Then a discussion about the methodological models adopted by the initiatives of the four studied groups follows, and comparative tables are elaborated in order to give visibility to the findings of the research. The study found that in the process of social innovation, design contributes with its methodologies, among other things, to the generation of social technologies aimed at a better quality of life for people, local development and social transformation.
212

Vertical Public Space : multi-story parking structures potential in public space / Vertikala offentliga rum : flervånings parkeringshus potential i offentliga rum

Eriksson, Jonathan January 2020 (has links)
Projektet syftar till att undersöka flervånings parkeringshus potential i omformning till offentliga utrymmen. Projektet grundar sig i ett alternativt framtidsscenario, där antalet bilar minskar i våra innerstadsområden i relation till ett mobilitetskifte kopplat till ny teknik och förändrade vanor i relaterat till mobilitet. Detta scenario kommer att generera en spatial konsekvens i en stadsmässig skala där ett flertal flervånings parkeringshus kommer bli tillgängliga för omformning i nya typer av användning samt funktioner. Detta projekt undersöker både potentialer och utmaningar i relation till omformningen av flervånings parkeringshus utifrån samtida praktik, tidigare forskning, innovativa projekt och en fältstudie av P-hus Godsmagasinet i Malmö, Sverige. Projektet resulterar i en undersökande designprocess i hur P-hus Godsmagasinet kan omformas till en offentlig plats utifrån en strategisk design utgångspunkt. Där design-metodiken är uppdelad i olika faser, för att samla och använda information samtidigt inom den pågående processen. Genom detta projekt, vill jag bidra till nya reflektioner och kunskap till de professioner som arbetar med urban utveckling, och framför allt lyfta fram flervånings parkeringshus potential, där jag anser att urban design besitter en viktig roll. Omformandet av flervånings parkeringshus är relaterat till hållbar stadsutveckling och är relevant till professioner som arbetar med samtidens och framtidens stadsmiljös problematik, där jag anser att detta projekt inte enbart illustrerar mitt eget intresse utan är relevant för ett flertal som arbetar med stadsmässiga miljöer. / The purpose of the project is to investigate the multi-story parking structures potential in relation to retrofit into public spaces. The project built on an alternative future scenario, there the amount of automobiles decreasing in our inner-city areas out from a mobility shift, linked to new technology and change of habits. This scenario will generate a spatial consequence on a city scale there several multi-story parking structures will become available for retrofitting into new types of uses and functions. This project investigates the potential and challenges of the retrofitting of multi-story parking structures out from contemporary practice, previous research, innovative projects and an actual case study of P-house Godsmagasinet in Malmö, Sweden. The work results in an exploratory design process in how P-house Godsmagasinet can be retrofitted into a public space out from a strategic design approach. There the design methodology is divided into different phases, to collect and use information simultaneously within the ongoing process. Through this project, I want to contribute with extended reflections and knowledge to the professions working with urban developments, and above all highlight the potential of the multi-story parking structure. The retrofitting of multi-story parking structures is related to sustainable urban development and is relevant in the professions dealing with contemporary and future urban environment issues, where I believe that this not only illustrates my own interest but is relevant to everyone who working with the urban environment.
213

Persons with functional difficulties as resources in ICT design processes

Persson, Hans January 2008 (has links)
Denna avhandling har sin grund i mina erfarenheter av att arbete med människor som har funktionsnedsättningar. Vanligtvis är denna grupp den sista en producent ser som sina kunder. Det är ganska vanligt att producenter gör olika produkter(produkter och tjänster) för personer med funktionsnedsättningar och en för andra. Om man istället, i designarbetet utgår från synsättet att de flesta personer vid någon tidpunkt och/eller plats har funktionssvårigheter så blir den potentiella kundgruppen större för produkten. Ursprunget för avhandlingen är ett projekt, vilket drevs av PTS (Post och Telestyrelsen), med syfte att identifiera vilka typer av stöd eller anpassningar personer med intellektuella funktionsnedsättningar har för att använda bredbandsbaserade tjänster. Resultatet i projektet pekade ut ett antal svårighetsområden där flertalet av dessa svårighetsområden inte var unika för denna grupp. Utifrån resultat i ovanstående projekt togs det fram en test-, utvärderings- och designmodell (TED-modellen) där ett av stegen använde en ”indikatorgrupp”. Syftet med modellen är att identifiera och ge underlag för att prioritera vilka svårighetsområden det fortsatta designarbetet skall fokuseras på. Indikatorgruppen består av individer med funktionssvårigheter som är relevanta i sammanhanget. Modellen tar vara på möjligheterna i ”design för alla” för att göra att göra bättre produkter för människorna. De empiriska studierna i denna uppsats är gjorda inom två områden. Den första är i ett designsammanhang, där fem olika hemsidor skulle tas fram och den andra är runt en studie av tre olika affärsarbetsplatser, där kassafunktionen var i fokus för studien. Resultatet i denna uppsats pekar ut en möjlig inriktning för en designmetodologi, vars målsättning är att få fram bättre produkter för en större grupp. Utgångspunkten är att använda människors olikheter som en möjlighet och inte som ett problem. Individer med funktionella svårigheter är en resurs för att finna nya innovationer vilket jag har benämnt ”the Lead of Need”. Med detta menar jag att individer med funktionella svårigheter, som har ett behov, en ide för en lösning, men inte har möjlighet att förverkliga denna. Om vi kan organisera en mötesplats för individer med ”the Lead of Need”, designers och utvecklare så har vi skapat ett ”Living lab” för nya innovationer. / This thesis has its roots in my experiences of working with people who have some forms of disability. Usually this group is the last group producers consider as their customers. It is quite common that producers make different products (and services) for individuals with disabilities and for others. If one instead takes the position, in the design work, that most people have some functional difficulties at some point in time or in place, then the potential customer group becomes larger for the product in question. The origin of this thesis is a project run by the Swedish Post and Telecom Agency (PTS), aiming to identify what kind of support or adaptation people with intellectual disabilities needs when using broadband based services. The result of the project pointed out areas of difficulties. Most areas of difficulties were not unique for this group. From the result of the PTS-project, a design and evaluation model (TED-model) was built, where one of the steps involved the use of an “indicator group”. The aim for this step is to identify and give basis for prioritizing areas of difficulty that the continued design work should focus on. The indicator group consists of individuals with functional difficulties relevant in a specified context. This method uses the possibilities of “design for all” as facilitator to design better products for more people. The empirical studies in this thesis were carried out within two areas. The first study was made in a design project, where five different web sites were to be designed, and the second one dealt with three different business workplaces in which the cashier workplaces was in focus. The results of this thesis point out a possible direction of a design methodology, whose objective is to create better products for larger group of people. The starting point is to use people's differences as a possibility for design, and not a problem. Individuals with functional difficulties constitute a resource for finding new innovations, which I have termed “the Lead of Need”. With this I mean individuals with functional difficulties, who have a need, an idea for a solution, but not the possibility to make it happen. If we can organise a meeting ground for individuals with “the Lead of Need”, designers, and developers, we will have created a “living lab” for new innovations. / QC 20101119
214

Systematische Identifizierung energieeffizienter Antriebskonfigurationen in Elektrofahrzeugen

Yuan, Shaohui, Hofmann, Wilfried 22 April 2024 (has links)
In der Projektierungsphase eines Elektrofahrzeugs entstehen optimale Antriebskonfigurationen erst durch die gezielte Kombination der einzelnen Antriebskomponenten. Um technisch vorteilhafte Auslegungszusammenhänge zu erkennen, ist eine systematische Untersuchung der Auslegungsfreiheitsgrade erforderlich. Diese Freiheitsgrade ergeben sich v. a. aus der Wahl der Auslegungsparameter, der Komponententypen und der Antriebstopologien. In diesem Artikel wird gezeigt, wie bereits in einer frühen Entwicklungsphase energieeffiziente Antriebskonfigurationen für Elektrofahrzeuge durch analytische Methoden identifiziert werden. Diese Methoden basieren grundsätzlich auf physikalischen Modellen und frei zugänglichen Datenblattangaben der Komponenten, die v. a. Energiespeicher, Wechselrichter, Elektromotor und Getriebe umfassen. Mithilfe dieser Methoden lässt sich der energetische Vergleich der zahlreichen Antriebskonfigurationen ohne großen Zeitaufwand durchführen. Die Ergebnisse führen schließlich zu einem informativen Auswahldiagramm, mit welchem aussagekräftige Prognosen zu den energieeffizienten Konfigurationen für beliebige Fahrprofile getroffen werden. / Optimal powertrain configurations develop only through the specific combination of individual powertrain components during the project planning phase of an electric vehicle. In order to identify the technically beneficial design correlations, a systematic investigation of the degrees of freedom in the powertrain design is necessary. The degrees of freedom arise primarily from the selection of design parameters, component types, and drive topologies. This article shows how energy-efficient powertrain configurations of electric vehicles can be identified at an early stage of development using analytical methods. These methods are based on physical models and freely available component data sheets. The components include a battery, inverter, electric motor, and gearbox. With these methods, the energy efficiency of various powertrain configurations can be evaluated quickly. The evaluation leads to an informative selection diagram, which allows forecasting energy-efficient configurations for different driving profiles.
215

Gripper Tool Designed for a Surgical Collaborative Robot / Gripdon designad för en kirurgisk kollaborativ robot

Andersson, Emma January 2019 (has links)
In surgery, suturing is the use of needle and thread to join cut and/or damaged anatomical structures together. This repair strategy is highly versatile and is universal for all types of surgery as the goal is to restore, repair or improve function and/or appearance. The needles are almost always curved in shape, and it is handled and maneuvered by surgeons with a special tool called: needle driver. The versatility of this setup has proven its worth over time as needle drivers are one of the indispensable instruments in all types of surgery. We are entering a future where robots can be programmed to execute tasks with much higher level of precision and speed compared to humans. Medical robotics in surgery has gained ground over the past decades due to promising clinical results. A straightforward step in this direction would be to create a solution that enables the robot to grip needle driver. The purpose of this study was to develop a gripper tool that enables a collaborative robot to perform suturing with one of the most common types of needle drivers used in surgery. The Double Diamond design framework was employed. The selected content in the predefined four phases were: 1) Discover: Observation, MoSCoW Prioritization, Brainstorming, Choosing a Sample, Fast Visualisation, 2) Define: Assessment criteria, 3) Develop: Physical prototyping 4) Deliver: Final testing and Evaluation. In the first phase, Discover, clinical and technical demands were formulated. In the second phase, Define, numerous design ideas were generated and drafted on paper whereof the one with highest assessment score was chosen for physical prototyping. In phase three, Develop, the selected design idea was modelled in cardboard, clay and silicon, and 3D printed. Multiple design iterations were guided by feedback from clinical and technical experts and resulted in a final prototype design that was accepted by the experts. In phase four, Deliver, the final prototype was subjected to final testing and evaluation. Observation of five live and one video recording of surgical procedures on real patients were made. The insights gained were confirmed with the lead and co-surgeons of each procedure and were summarized in 24 clinically important observations relevant for the gripper tool design. Careful analysis of the previously designed gripper tool, live observation of the robot’s motion pattern and range, and interview with robotic engineer were summarized in ten technically important observations. The observations were then used to formulate the clinical and technical demands that the gripper tool design aims to fulfill, followed by prioritizing the demands and design features according by MoSCoW method and brainstorming on how to improve previous gripper tool design. To limit the scope of the design challenge, one of the five types of needle drivers used in pediatric heart surgery in Lund was selected in the method Choosing a Sample. To further characterize the clinical and technical demands, a test bench was set up to Define and measure force vectors applied on the needle driver when held by a surgeon during suturing. The radial forces vectors in six directions perpendicular to the tip of the needle driver ranged from 1.6 N to 3.8 N. The axial force along the length of the needle driver was 7.6 N towards the tip and 8.4 N towards the back end. The clockwise and counterclockwise torque along the length axis of the needle driver was 0.2 Nm and 0.18 Nm, respectively. The set of defined demands were sufficient to sketch numerous ideas of gripper tool designs according to the Fast Visualization method. These designs were then used in the Define phase to communicate the design ideas with surgeons, robotic and product development engineers. The most promising idea was advanced to the Develop phase where physical prototypes were produced in cardboard, clay and silicon and 3D printed. Inadequacies were found during design feedback with interviews and testing together with clinical and technical experts, and design actions were taken to arrive at the final prototype. The final prototype was brought into the Deliver phase for final testing and evaluation. The gripper tool could handle lager force loads than the human surgeon in all the stability tests. However, deflection of the needle driver occurred with the gripper tool unlike when the surgeon was subject to stability testing. One pediatric heart surgeon and one robotic engineer was asked to generate a composite score of fulfillment rate from 1–5, where 1 is bad, 3 satisfactory, and 5 excellent after final testing of the gripper tool was carried out. The final prototype of the gripper tool fulfills all clinical and technical demands at the level of 4, and 3–5, respectively. In conclusion, the design methodology used in this study was useful in the development of a gripper tool design that respects both clinical and technical demands. This suggest that the methodology may be used in similar setting of design challenges in the field between medical and technical innovation. The gripper tool fulfilled the demands, although further refinement in the choice of material, further testing and investigation of regulatory aspects are required before it can be implemented in the operating room. / Vid operation är suturering användningen av nål och tråd för att sammanfoga snittad och/eller skadade anatomiska strukturer. Denna reparationsstrategi är mycket mångsidig och universell för alla typer av kirurgi eftersom målet är att återställa reparera eller förbättra funktion och/eller anatomisk defekt. Nålarna är nästan alltid krökta i sin form och de hanteras och manövreras av kirurgerna med ett speciellt verktyg som kallas: nålförare. Mångsidigheten i denna uppställning har visat sig över tid eftersom nålförare är ett av de oumbärliga instrumenten vid alla typer av operationer. Vi går in i en framtid där robotar kan programmeras för att utföra uppgifter med mycket högre precision och hastighet jämfört med människor. Medicinska robotar inom kirurgi har varit på frammarsch senaste årtionden på grund av goda kliniska resultat. Ett steg i denna riktning skulle vara att skapa en lösning som gör det möjligt för en robot att greppa nålföraren. Syftet med denna studie var att utveckla ett gripdon som möjliggör för en kollaborativ robot att utföra suturering med hjälp av en av de vanligaste typerna av nålförare som används vid operation. Design metodiken Double Diamond användes för att beskriva design processensen. Det valda metoderna i de fyra för definierade faser var: 1) Discover: Observation, MoSCoW Prioritization, Brainstorming, Choosing a Sample, Fast Vissualization, 2) Define: Assessment criteria, 3) Develop: Physical Prototyping, 4) Deliver: Final testing and Evaluation. I första fasen, Discover, formulerades kliniska och tekniska krav. I den andra fasen, Define, definierades flera designidéer som skissades på papper, varav den med den högsta poängen valdes i Assessment criteria. I fas tre, Develop, modellerades den valda designidén i kartong, lera och silikon samt 3D-printades. Flera designiterationer gjordes baserat på feedback från kliniska och tekniska experter vilket resulterade i en slutlig prototypdesign som godkändes av experterna. I fas fyra, Deliver, testades och utvärderades den slutliga prototypen. Observation av fem realtids och en videoinspelning av kirurgiska ingrepp på riktiga patienter gjordes. Insikterna som gjordes bekräftades med kirurgerna som genomförde operationen och sammanfattades i 24 kliniskt viktiga observationer som var relevanta för gripdon designen. Noggrann realtids observation av robotens rörelsemönster samt analys av det tidigare utformade gripdonen och intervju med en robotingenjör sammanfattades i tio tekniskt viktiga observationer. Observationerna användes för att formulera kliniska och tekniska krav som gripdons designen strävar efter att uppfylla, följt av prioritering av kraven och designegenskaper enligt MoSCoW-metoden och brainstorming kring hur tidigare gripdons design kan förbättras. För att begränsa designutmaningens omfattning valdes en av de fem typer av nålförare som används vid barnhjärtkirurgi i Lund genom metoden Chossing a sample. För att ytterligare karakterisera de kliniska och tekniska kraven upprättades en testbänk för att definiera och mäta kraftvektorer som appliceras på nålföraren när den hålls av en kirurg under suturering. De radiella krafterna i sex riktningar vinkelrätt mot nålförarens spets varierade från 1,6 N till 3,8 N. Den axiella kraften längs nålförarens längd var 7,6 N mot spetsen och 8,4 N mot bakänden. Medurs och moturs vridmoment längs nålförarens längdaxel var 0,2 Nm respektive 0,18 Nm. Dom definierade kraven låg till grund för skisser av flertal gripdondesign idéer enligt Fast Visualization. Dessa skisser användes sedan i Define fasen för att kommunicera designidéer med kirurger samt robot- och produktutvecklingsingenjörer. Den mest lovande idén togs till Develop fasen där fysiska prototyper togs fram i kartong, lera och silikon samt genom 3D-printning. Förbättringspunkter hittades under testning och återkoppling med intervjuer tillsammans med kliniska och tekniska experter. Designåtgärder baserat på återkopplingen gjordes för att komma fram till den slutliga prototypen. Slutlig testning och utvärdering av den slutliga prototypen genomfördes i Deliver fasen. Gripdons designen kunde hantera större belastningar än den mänskliga kirurgen i alla stabilitetstester. Böjning av nålföraren uppstod dock i testerna med gripverktyget till skillnad från testerna med kirurgen var föremål för stabilitetsprovning. En barnhjärtkirurg och en robotingenjör poängsatte uppfyllnadsgrad av de kliniska respektive tekniska kraven efter att slutlig testning av gripdonet utförts. Uppfyllnadsgraden poängsattes från 1–5 där 1 var dålig, 3 tillfredsställande och 5 utmärkt. Gripdonets slutliga prototyp uppfyller alla kliniska och tekniska krav på nivå 4 respektive 3–5. Designmetodiken som användes i denna studie var användbar för utvecklingen av gripdon som uppfyller både de kliniska och tekniska kraven. Detta tyder på att denna metod kan användas i liknande designutmaningar inom området mellan medicinsk och teknisk innovation. Gripdonet uppfyllde kraven även om ytterligare förfining i materialvalet, ytterligare testning och undersökning av regulatoriska aspekter krävs innan den kan användas under riktiga operationer i operationssalen.
216

<b>PHYSICS INSPIRED AI-DRIVEN PHOTONIC INVERSE DESIGN FOR HIGH-PERFORMANCE PHOTONIC DEVICES</b>

Omer Yesilurt (19435210) 19 August 2024 (has links)
<p dir="ltr">This thesis presents novel methodologies to integrate AI-driven and physics-inspired methodologies into photonic inverse design, setting new benchmarks for high-performance photonic devices in different branches of photonics. By blending advanced computational techniques with the foundational principles of electromagnetism, this research tackles key challenges in optimizing device efficiency, robustness, and functionality. The aim is to propel photonic technology beyond its current capabilities, offering transformative solutions for a range of novel applications.</p><p dir="ltr">The first major contribution focuses on adjoint-based topology optimization for on-chip single-photon coupling. We developed an adjoint topology optimization scheme to design high-efficiency couplers between photonic waveguides and single-photon sources (SPSs) in hexagonal boron nitride (hBN). This algorithm addresses fabrication constraints and SPS location uncertainties, achieving a remarkable average coupling efficiency of 78%. A library of designs is generated for different positions of the hBN flake containing an SPS relative to a silicon nitride (SiN) waveguide. These designs are then analyzed using dimensionality reduction techniques to investigate the relationship between device geometry and performance, infusing the design process with deep physical intuition and insight.</p><p dir="ltr">The second key advancement is presented through a neural network-based inverse design framework specifically developed for optimizing single-material, variable-index multilayer films. This neural network-driven technique, supported by a differentiable analytical solver, enables the realistic design and fabrication of these multilayer films, achieving high performance under ideal conditions. The approach also addresses the challenge of bridging the gap between these ideal designs and practical devices, which are subject to growth-related imperfections. By incorporating simulated systematic and random errors—reflecting actual deposition challenges—into the optimization process, we demonstrate that the neural network, initially trained to produce the ideal device, can be reconfigured to create designs that compensate for systematic deposition errors. This method remains effective even when random fabrication inconsistencies are present. The results provide a practical and experimentally viable strategy for developing single-material multilayer film stacks, ensuring reliable performance across a wide range of real-world applications.</p><p dir="ltr">The final cornerstone of this research investigates the two-stage inverse design of superchiral dielectric metasurfaces. We propose a two-stage inverse design scheme for dielectric lossless metasurfaces with central superchiral hot spots. By leveraging the excitation of high-quality factor modes with low mode volumes, we achieve up to 19,000-fold enhancements of optical chirality. This method extends the local density of field enhancements for non-chiral fields into the chiral regime and significantly surpasses previous enhancements in superchiral field generation. Our results open new avenues in chiral spectroscopy and chiral quantum photonics, exemplifying the powerful synergy of AI techniques and physics-based design principles in creating highly innovative and functional photonic structures.</p><p dir="ltr">Collectively, the methodologies developed in this thesis signify a major advancement in the field of photonic inverse design. By merging AI-driven techniques with rigorous physics-based optimization frameworks, this research paves the way for the next generation of photonic devices.</p>
217

Démarche méthodologique pour la conception préliminaire et interactive / Methodological approach for interactive preliminary-design

Ríos zapata, David 14 December 2018 (has links)
Les processus de prise de décision dans la conception demandent aux concepteurs de prioriser les spécifications et les variables afin de développer des solutions plus proches des objectifs du produit. Néanmoins, la taille des informations est souvent volumineuse et difficile à comprendre : garder la trace de la liste des variables dépendantes, des variables indépendantes et des objectifs de conception est une tâche complexe, avec potentiellement des retraitements et perte de temps, surtout lorsqu'il est nécessaire d'identifier quand une modification sur une variable peut avoir un impact sur les performances du produit.L'objectif de cette thèse est de proposer une méthode qui permettant d'obtenir un trade-off entre les objectifs de conception. Ce trade-off est basé sur deux aspects : i) le développement d'un modèle de traçabilité, gérant les informations à partir des exigences du produit (dans le domaine linguistique) jusqu'à la définition des variables (dans le domaine des nombres réels). ii) un cadre d’amélioration de la conception, fondé sur la définition des fonctions de désirabilité des objectifs de conception. La propagation de ces fonctions jusqu’à les variables de conception permettent de calculer la combinaison de valeurs qui maximisent l’index global de désirabilité de la solution.La proposition de thèse peut être comprise comme une approche hybride, comprenant une partie exploratoire interactive et une partie interactive inductive. Sur la partie exploratoire, les concepteurs peuvent modifier les variables à l'aide d'outils visuels afin de comprendre en temps réel l'impact de ces modifications sur les objectifs de conception. Sur la partie inductive, les concepteurs utilisent une méthode de pré-dimensionnement proposée, qui calcule les valeurs des variables qui maximisent la désirabilité des objectifs de conception. Cette méthode fonctionne sur un environnement de conception multidisciplinaire, avec des problèmes convexes ou non-convexes. / Preliminary design decision-making processes are related to the prioritisation of design specifications and variables in order to develop solutions that are closer to product's requirements. Nevertheless, the size of the information is often large and hard to understand: keeping in track the list of dependent variables, independent variables and design objectives is a challenging task, with potentially reprocessing and loss of time, especially when it is necessary to identify how a modification on a variable might impact the performance of the product.The objective of this thesis is to generate a method that can obtain a trade-off among the design objectives desirability. This trade-off process is supported on two aspects: i) the development of a traceability model, managing information from the input requirements (in the linguistic field) up to the variables definition (in the real numbers field). ii) A design amelioration framework, based on the definition of the design objectives desirability functions; the propagation of these functions until design variables allow to calculate the combinations of values that maximise the global desirability of the solution.The proposal of the thesis can be understood as a hybrid approach, including an interactive exploratory part and an inductive interactive part. On the exploratory part, designers can modify the variables using visual tools in order to understand in real time how these modifications have an impact on the design objectives. On the inductive part, designers make use a proposed pre-sizing method that calculates the values of the variables that maximise the desirability of the design objectives. This proposal is developed to perform on a multidisciplinary design environment, facing, either convex and non-convex problems.
218

Desenvolvimento de um sistema dinamicamente reconfigurável baseado em redes intra-chip e ferramenta para posicionamento de módulos. / Development of a dynamically reconfigurable systems under noc and CAD for modules mapping.

Raffo Jara, Mario Andrés 05 February 2010 (has links)
Os sistemas dinamicamente reconfiguráveis (SDRs) são uma alternativa para o desenvolvimento de sistemas sobre silício baseados em circuitos programáveis (SoPC), cujo principal beneficio é o bom aproveitamento da área do dispositivo. Sendo neles implementados circuitos que representam as tarefas que devem operar numa etapa específica do tempo de operação do sistema, permitem um menor consumo de área e de energia, parâmetros importantes nos sistemas portáveis. Isto tem gerado muito interesse no que se refere às metodologias de projeto utilizando FPGAs (Field Programmable Gate Arrays) dinamicamente reconfiguráveis (DRFPGAs) e à definição de um meio de comunicação estruturado para tratar da transferência de dados entre as partes reconfiguráveis e as fixas, mas estas tarefas, assim como a concretização de sua comunicação, seguem sendo ainda essencialmente manuais, devido à falta de metodologias de projeto e ferramentas de CAD que simplifiquem o projeto de SDRs. Este trabalho foca uma das limitações mais efetivas para a adoção da reconfiguração dinâmica: a falta de ferramentas de CAD que suportem o projeto de SDRs, inclusive os baseados em redes intra-chip (NoCs), em particular, no posicionamento dos módulos. Neste trabalho, uma arquitetura para SDRs baseado em NoCs é proposta e um algoritmo de posicionamento dos módulos de um SDR baseado em aspectos reais da família do DRFPGAs é desenvolvido, dentro de uma ferramenta denominada DynoPlace. Desenvolveu-se também um modelo de validação e simulação de SDRs, em tempo de operação, utilizando-se a técnica de chaveamento dinâmico de circuitos. Para o estudo do caso, de validação da arquitetura e metodologia, propõe-se uma aplicação teste baseada em computação de operações aritméticas. A metodologia de simulação permite determinar o tempo da reconfiguração e verificar o comportamento do SDR no momento da reconfiguração. A ferramenta DynoPlace permite gerar os arquivos de restrição de usuário (UCF) de posicionamento dos módulos do SDR no DRFPGA Virtex-4LX25. Este contém informações do posicionamento dos módulos do sistema, dos dispositivos usados para as entradas e saídas do sistema além do posicionamento dos bus-macros. Com os arquivos gerados pela metodologia e ferramenta DynoPlace, pode-se executar com sucesso os scripts da metodologia Early Access da Xilinx para gerar o SDR de forma automática. / Dynamically Reconfigurable Systems (DRSs) are an alternative for developing Systems on a Programmable Chip (SoPC), being the efficient use of device\'s area one of its main advantages. Circuits implemented as DRSs represent tasks which must be active in specific times into the system operation, allowing area and energy saving, which is an important goal for portable systems. This has generated interests on the design methodology using Dynamically Reconfigurable Field Programmable Gate Arrays (DRFPGAs) and on the definition of communication systems for handling data transfer between static and reconfigurable partitions. However, these tasks, as well as the communication structure, are still carried out manually due to lack of design methodologies and CAD tools applied to DRSs design. This work focuses on the one of main drawbacks to the adoption of dynamic reconfiguration methods: the absence of CAD tools which support DRS designs, specifically, in the module positioning task, included, for those based on Network-on-Chip (NoCs). In this work, an architecture for DRSs based on NoCs is presented and an algorithm for module positioning is developed in a tool called DynoPlace as well, based on real specifications of DRFPGAs families. It is also developed a run-time simulation and validation model for DRSs, through a dynamic circuit switching technique. For the validation of architecture and methodology study case, an application test based on arithmetic operations has been proposed. The simulations methodology allows to determine the reconfiguration time and verify the DRS behavior at the moment of reconfiguration. The DynoPlace tool allows to generate User Constraint File (UCF) of DRS\'s modules positioning for the DRFPGA Virtex-4LX25. This file contains information of modules positioning in the system, of the devices used for inputs and outputs of the system, and the positioning of bus-macros. After the files generation by the methodology, and the DynoPlace tool, it is possible to successfully execute the Early Access scripts for generating the DRS automatically.
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Ensino a Distância: Uma análise do design de um curso de Cálculo com um olhar no conteúdo de limites e continuidade de uma variável real

Forster, Sandra Regina Leme 03 May 2007 (has links)
Made available in DSpace on 2016-04-27T16:58:09Z (GMT). No. of bitstreams: 1 Sandra Regina Leme Forster.pdf: 14992538 bytes, checksum: 2360f28c33cee2356493723f45f981f6 (MD5) Previous issue date: 2007-05-03 / The aim of this study is to present the material developed to the contents of Limit a Continuity of Functions of a Real Variable (Limite e Continuidade de Funções de uma Variável Real); demonstrate the analysis of the production of the applicable methodologies for the subject Differential and Integral Calculus II (Cálculo Diferencial e Integral II), one of the units required by the undergraduate academic degree in Bachelor of Mathematics, a program developed in a distance learning basis held by a university in São Paulo; as well as present suggestions to improve the course mentioned above. The theoretical base built in this paper was founded in two theories: the Semiotic Representation Registers Theory, by Raymond Duval, used in researches related to knowledge acquisition and organizing learning situations, and the Interactionist Theory, which is rooted in the studies of Piaget and Vygotsky, authors that forego the distance learning programs. This theory has been interpreted and rewritten by authors that work with distance learning programs and state that interaction promotes learning in any educational environment. This study also exposes what the researcher understands by distance learning and the media used in this kind of learning program. This paper consists of a methodology research based in design where quantitative and qualitative analyses were used, especially, the triangular analysis of data collected through observations of several natures. The results obtained through this research show that: the material and the methodologies applied to the course were well accepted, however, the students prefer the printed material. The students that frequently interacted during the course had better learning results. The development of activities with different types of semiotic representation registers provoke questioning, aid the learning of mathematics concepts and allow to observe if the concept was acquired by the student. The material developed to Continuity teaching was not sufficient to promote learning and must be reorganized / Este estudo tem como objetivo apresentar o material elaborado para os conteúdos de Limite e Continuidade de Funções de uma Variável Real; demonstrar a análise da produção e das metodologias aplicadas na disciplina de Cálculo Diferencial e Integral II do curso de Licenciatura Plena em Matemática na modalidade à distância de uma universidade em São Paulo; como também apresentar sugestões para o aperfeiçoamento do curso em questão. A fundamentação teórica presente neste estudo foi construída a partir de duas teorias: a Teoria dos Registros de Representações Semióticas, de Raymond Duval, utilizada em pesquisas referentes à aquisição de conhecimento e à organização de situações de aprendizagem, e a Teoria Interacionista, que possui raízes nos estudos de Piaget e Vygotsky, autores que antecedem a Educação a Distância. Essa teoria foi interpretada e reescrita por autores que vivenciam a modalidade de ensino a distância e afirmam que a interação promove a aprendizagem em qualquer ambiente educacional. Além dessas teorias, este trabalho expõe o que se entende por Educação a Distância e as mídias utilizadas nessa modalidade de ensino. Este estudo trata-se de uma pesquisa de metodologia de design em que se faz o uso das análises quantitativas, qualitativas e, principalmente, da triangulação dos dados coletados em observações de diversas naturezas. Os resultados obtidos por meio desta pesquisa apontam que: o material e as metodologias aplicadas ao curso foram bem aceitos, porém há preferência por materiais da mídia impressa. Os alunos que interagiram com freqüência durante o curso obtiveram melhores resultados na aprendizagem. As atividades com diferentes tipos de registros de representações semióticas provocam questionamentos, favorecem a aprendizagem dos conceitos matemáticos e permitem observar se o conceito foi adquirido pelo aluno. O material elaborado para o ensino de Continuidade não foi suficiente para promover a aprendizagem e deve ser reorganizado
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Metodologia de projeto de atuador eletromagnético linear para sistemas de suspensão semiativa e ativa

Eckert, Paulo Roberto January 2016 (has links)
Este trabalho apresenta uma metodologia de projeto de atuadores eletromagnéticos lineares inovadora para aplicação em sistemas de suspensão semiativa e ativa. A metodologia, apresentada na forma de fluxograma, define critérios para determinar os requisitos de força e curso que um atuador deve desenvolver considerando um sistema mecânico vibratório com um grau de liberdade com excitação harmônica de base quando o método de controle skyhook é aplicado. Um atuador eletromagnético linear de bobina móvel com duplo arranjo de quase-Halbach que apresenta elevada densidade de força, reduzida massa móvel, ausência de força de relutância e baixa ondulação de força é definido como estudo de caso. Um modelo numérico parametrizado em elementos finitos do comportamento eletromagnético de um passo polar do dispositivo é criado e analisado, considerando restrições dimensionais, com os objetivos de projeto definidos como: elevada densidade de força e reduzida ondulação de força com acionamento brushless CA. Com base no modelo de um passo polar do dispositivo, define-se o volume ativo que o mesmo deve apresentar e, a partir deste, todas as dimensões são definidas de forma a atender os requisitos de projeto. Uma vez definidas as dimensões do atuador com base no modelo eletromagnético, realiza-se a modelagem térmica numérica que permite avaliar qual a máxima densidade de corrente elétrica aplicável de forma que a temperatura, estipulada como máxima, nos enrolamentos não seja excedida. Ainda, a distribuição térmica permite determinar a temperatura de operação dos ímãs permanentes que têm curva de operação dependente da temperatura. A partir dos resultados da simulação térmica e do modelo eletromagnético para um passo polar, realizou-se o acoplamento eletromagnético-térmico por meio da correção das propriedades dos ímãs permanentes e aplicando uma densidade de corrente eficaz dependente das dimensões do modelo parametrizado. O modelo acoplado é simulado e analisado, de modo que as dimensões finais do atuador podem ser obtidas atendendo aos mesmos objetivos de projeto previamente mencionados, respeitando os limites de operação térmica. Adicionalmente, são apresentados modelos analíticos do comportamento eletromagnético e térmico do atuador que podem servir de base para implementação da metodologia proposta, se esta for baseada em modelos analíticos, e podem futuramente ser empregados para a aplicação de otimização matemática do dispositivo. Por fim, um protótipo do dispositivo é construído de forma a validar a metodologia proposta. Com este protótipo são realizados ensaios de densidade de fluxo magnético no entreferro, tensão induzida a vazio, força estática e ensaio dinâmicos com o dispositivo instalado em uma bancada de testes de vibrações controladas desenvolvida durante o projeto. Os resultados mostram a eficácia da metodologia proposta, uma vez que os resultados experimentais mostraram boa concordância com os resultados esperados. / This work presents an innovative linear electromagnetic actuator design methodology for application in semi-active and active suspension systems. The methodology, synthesized in a flowchart, sets criteria to determine requirements such as axial force and stroke that an actuator should develop considering a vibration system with one degree of freedom with harmonic base excitation when the skyhook control method is applied. A linear moving-coil electromagnetic actuator with dual quasi-Halbach arrays of permanent magnets that presents high force density, low moving-mass, no reluctance force and low force ripple is defined as a case study. A finite element numerical parameterized model that describes the electromagnetic behavior of one pole pitch of the device is created and analyzed, considering dimensional constraints, with the design objectives defined as: high force density and low ripple of force with brushless AC drive. Based on the model of one pole pitch of the device the active volume and all dimensions are defined in order to meet the design requirements. Once the actuator dimensions are defined, based on the electromagnetic model, a numerical thermal model was constructed, which allows to evaluate the maximum applicable electric current density so that the maximum temperature at the windings is not exceeded. Furthermore, the thermal distribution gives the operating temperature of the permanent magnets, which present performance highly dependent on temperature. With the results of the thermal simulation, the electromagnetic-thermal coupling is performed by correcting permanent magnet properties and by applying a parametric-dependent effective current density. The coupled model is simulated and analyzed so that the final dimensions of the actuator can be obtained with the same design objectives previously mentioned, while respecting thermal operating limits. In addition, the work presents analytical models of the electromagnetic and thermal behavior of the actuator that can be the basis for implementation of the proposed methodology, if it is based on analytical models, and can further be used for the application of mathematical optimization of the device. Finally, a prototype was built to validate the proposed method. Measurements were carried out to assess magnetic flux density in the air gap, open-circuit induced voltage, static force and dynamic tests with the device installed in a test bench that was developed during this work. The results show the effectiveness of the proposed method since experimental results have shown good agreement with the expected results.

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