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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.
11

Contribution à la caractérisation de composants sub-terahertz / Contribution on the characterization of sub THz components

Potéreau, Manuel 24 November 2015 (has links)
La constante amélioration des technologies silicium permet aux transistors bipolaires à hétérojonction (HBT) SiGeC (Silicium-Germanium : Carbone) de concurrencer les composants III-V pour les applications millimétriques et sous-THz (jusqu’à 300GHz). Le cycle de développement de la technologie (caractérisation-modélisation-conception-fabrication) nécessite plusieurs itérations, entraînant des coûts élevés. De plus, les méthodologies de mesure doivent être réévaluées et ajustées pour adresser des fréquences plus élevées. Afin de réduire le nombre d’itérations et de permettre la montée en fréquence de la mesure, un travail de fond sur la première étape, la caractérisation, s’avère indispensable.Pour répondre à cette exigence, une description et une étude des instruments de mesure (VNA) est réalisée dans un premier temps. Un état de l’art des méthodes de calibrage permet de choisir la solution la plus pertinente pour la calibration sur puce valable dans la gamme de fréquences sous-THz. Ensuite, après avoir relevé plusieurs défauts dans la méthode choisie (à savoir la méthode Thru-Reflect-Line : TRL), des solutions sont proposées concernant la modification des calculs des coefficients d’erreur et également en modifiant les standards utilisés durant le calibrage. Finalement, une étude sur les méthodes d’épluchage est réalisée. Une amélioration est proposée par la modification de deux standards évitant le principal problème de l’état de l’art, la surcompensation des composants parasites. / The continuous improvement in Silicon technologies allows SiGeC (Silicon-Germanium-Carbon) heterojunction bipolar transistors (HBT) to compete with III-V components for millimeter wave and sub-THz (below 300GHz) applications. The technology development cycle (characterization, modeling, design and fabrication) needs several iterations resulting in high costs. Furthermore, the measurement methodologies need to be re-assessed and modified to address higher measurement frequencies. In order to reduce the number of iterations and to allow reliable measurement in the sub-THz band, the characterization procedure has been revisited.First, a description and investigation of the measurement instrument (VNA) has been made. After exploring all possible calibration methods, the best candidate for an “on-wafer” calibration for the sub-THz frequency range has been selected. Then, after analyzing the limits of the chosen calibration method (Thru-Reflect-Line: TRL), workarounds are proposed, by modification of the errors coefficients calculation and by changing the standards used during the calibration process. At last, a study concerning the de-embedding methods is carried out. It is shown, that using two new standards helps to reduce the over-compensation of parasitic components.
12

Conception et développement d’étalons pour la mesure des paramètres S en mode mixte de circuits intégrés et méthodes associées / Design and development standards for mixed-mode S-parameters measurement of integrated circuits and associated methods

Pham, Thi Dao 12 September 2019 (has links)
Des circuits différentiels sont largement utilisés pour la conception de composants hyperfréquences principalement en raison de leur meilleure immunité au bruit. Ces circuits doivent être caractérisés au moyen de paramètres S en mode mixte (mode différentiel, mode commun et conversion entre les deux modes). De plus, la tendance à la miniaturisation et à l’intégration des dispositifs hyperfréquences conduit à l’utilisation de structures planaires ou coplanaires telles que les lignes micro-ruban ou les lignes coplanaires. La structure coplanaire avec les conducteurs déposés à la surface supérieure du substrat évite de réaliser des trous métallisés, et donc simplifie la fabrication et empêche l’apparition d’éléments parasites. Du point de vue de la métrologie électrique, il est nécessaire d’établir la traçabilité des mesures de paramètres S en mode mixte au Système International d’unités (SI). La méthode d’étalonnage Multimode Thru – Reflect – Line (TRL), dérivée de l’étalonnage TRL couramment utilisée pour les mesures de paramètres S de circuits asymétriques, est bien adaptée à cette problématique. En effet, l’impédance caractéristique, qui définit l’impédance de référence du système de mesure, peut être obtenue à partir des constantes de propagation déterminées lors de la procédure Multimode TRL et des capacités linéiques en DC.Nous présentons la première conception et la réalisation d’un kit d’étalonnage Multimode TRL et d’un kit de vérification à base des lignes coplanaires couplées en configuration « Ground – Signal – Ground – Signal – Ground » sur un substrat de quartz (SiO2) à faibles pertes diélectriques pour des mesures de paramètres S en mode mixte sur wafer de 1 GHz à 40 GHz. Les mesures sont effectuées à l’aide de deux méthodes : l’approche « one-tier » basée sur la procédure d’étalonnage Multimode TRL afin de déterminer et de corriger l’ensemble des erreurs systématiques ou bien l’approche « two-tier » qui fractionne la détermination et la correction des termes d’erreur en deux étapes dont la deuxième est associée à la méthode Multimode TRL. La faisabilité et la validation de ces techniques sont démontrées par des mesures d’éléments de vérification, constitués de lignes (adaptées, désadaptées et déséquilibrées) et d’atténuateurs en T, qui montrent un très bon accord entre les valeurs mesurées et simulées.La propagation des incertitudes est évaluée soit à partir du calcul des dérivées partielles à l’aide de l’outil Metas.Unclib ou bien par simulation numérique basée sur la méthode de Monte Carlo. La précision des mesures de paramètres S sous pointes dépend des sources d’influence attribuées aux mesures et aux imperfections des étalons telles que le bruit et la non-linéarité de l’analyseur de réseaux vectoriel, la stabilité des câbles, la répétabilité des mesures et la sensibilité dans la réalisation des étalons. Faute de temps, nous nous limitons à estimer la propagation d’incertitudes liées à la répétabilité de mesure des étalons et du dispositif sous test (DST) aux valeurs des paramètres S corrigés de la ligne désadaptée. Les résultats montrent que l’approche des dérivées partielles basée sur une approximation de la série de Taylor au premier ordre ne peut pas être utilisée avec précision à cause de l’influence significative de la non-linéarité des fonctions mathématiques de l’algorithme Multimode TRL. La méthode Monte Carlo s’avère alors plus précise bien qu’elle nécessite des temps de calcul très longs. / Differential circuits are widely used in the design of high frequency components mainly because of their better noise immunity. These circuits can be characterized using mixed-mode S parameters (differential- and common-mode S-parameters and cross-mode terms). Furthermore, the trend toward miniaturization and integration of microwave devices increases the need for planar or coplanar microwave integrated circuits such as micro-strip lines or coplanar waveguides. The ungrounded coplanar waveguide structure with all the conductors located on the same side of the substrate eliminates the need for via-holes, and thus simplifies manufacturing and prevents the appearance of some parasitic elements. From the viewpoint of electrical metrology, it is necessary to establish the traceability of the mixed-mode S-parameter measurements to the International System of Units (SI). The Multimode Thru-Reflect-Line (TRL) calibration method, derived from the commonly-used TRL calibration for S-parameter measurements of single-ended circuits, is particularly well suited for this purpose as the standards are traceable via dimensional measurements. The characteristic impedance, which defines the reference impedance of the measurement system, can be achieved from the propagation constants determined during the Multimode TRL calibration and the capacitances per unit length of the transmission line.We present the first design and realization of Multimode TRL calibration and verification kits using coupled coplanar lines in the "Ground - Signal - Ground - Signal - Ground" configuration on quartz (SiO2), the low-loss substrate, for on-wafer mixed-mode S-parameter measurements from 1 GHz to 40 GHz. Measurements are performed using two methods: the “one-tier” technique, based on the Multimode TRL calibration procedure, determines and corrects all systematic errors. The “two-tier” approach, in which the Multimode TRL is applied at the second-tier, is applied to measurement data that were partially corrected by the first calibration. The feasibility and the validation of the methods are demonstrated by measurements of matched, mismatched and unbalanced lines and T-attenuators showing good agreement between simulated and measured results.The propagation of uncertainty can be derived by the calculation of partial derivatives using the Metas.Unclib tool or by the numerical approach based on the Monte Carlo technique. The accuracy of on-wafer S-parameter measurements depends on sources of influence attributed to the measurements and to the imperfections of the standards such as the VNA noise and non-linearity, the cable stability, the measurement repeatability, and the sensitivity in calibration standards’ realization. We focus, first and foremost, on the propagation of uncertainties related to the repeatability of the standards and the device under test measurements to the corrected mixed-mode S-parameters of the mismatched line. The results show that the partial derivatives approach based on an approximation of the first-order Taylor series cannot be accurately used due to the significant influences of non-linear functions in the Multimode TRL algorithm. The Monte Carlo method is then more precise although it requires very long computation time.
13

[pt] MONITORAMENTO E AVALIAÇÃO DE PROJETOS DE PD(E)I DE PRODUTOS E SISTEMAS COMPLEXOS PARA A ÁREA DE DEFESA: PROPOSIÇÃO DE CRITÉRIOS, INDICADORES E MÉTRICAS / [en] MONITORING AND EVALUATION OF RD(AND)I PROJECTS OF COMPLEX PRODUCTS AND SYSTEMS FOR THE DEFENSE AREA: PROPOSITION OF CRITERIA, INDICATORS AND METRICS

NATALIA CURADO CARNEIRO 15 June 2023 (has links)
[pt] O objetivo desta dissertação é propor e aplicar um modelo conceitual para monitorar e avaliar projetos de pesquisa, desenvolvimento e inovação (PDeI) de novos produtos e sistemas complexos (CoPS), mediante o emprego de uma abordagem metodológica, que integra a escala Technology Readiness Level (TRL) à ferramenta Stage-Gate e emprega dois métodos multicritério de apoio à decisão. A metodologia compreende: (i) pesquisa bibliográfica e documental sobre os temas centrais da pesquisa; (ii) construção do modelo conceitual de monitoramento e avaliação (MA) de projetos de PD(e)I de CoPS de defesa, baseado na ferramenta Stage-Gate e na escala TRL; (iii) emprego do método Analytic Hierarchy Process (AHP) em dois momentos, sendo o primeiro para definir os pesos dos critérios para validação da qualidade dos indicadores de desempenho referentes a projetos de PD(e)I e o segundo para atribuir pesos aos critérios de avaliação dos referidos projetos no portões de decisão (gates); (iv) emprego do método TOPSIS para validação da qualidade dos indicadores de desempenho; e (v) aplicação do modelo proposto, tendo como foco um projeto de PD(e)I de CoPS em andamento no Centro Tecnológico do Exército (CTEx), visando evidenciar seu potencial de replicabilidade para os demais projetos de PD(e)I de CoPS daquele Centro. Destaca-se como resultado principal um modelo inovador de monitoramento e avaliação de projetos de PD(e)I de CoPS de defesa, que poderá ser aplicado no CTEx e em outras instituições de CT(e)I, que buscam a excelência em gestão da inovação, particularmente quando enfrentam os desafios do desenvolvimento de PD(e)I de CoPS. Os resultados do estudo empírico conduzido neste contexto organizacional mostraram que é possível empregar, de forma integrada e efetiva, a ferramenta Stage-Gate e a escala TRL para monitorar e avaliar projetos de PD(e)I de CoPS de defesa ao longo de seu desenvolvimento. / [en] The objective of this dissertation is to propose and apply a conceptual model for monitoring and evaluating research, development, and innovation (RDandI) projects of new complex products and systems (CoPS), using a methodological approach that integrates the Technology Readiness Level (TRL) scale with the Stage-Gate tool and employs two multicriteria decision support methods. The methodology comprises: (i) bibliographic and documentary research on the central themes of the research; (ii) development of the conceptual model for monitoring and evaluation RD(and)I projects of CoPS for the defense area, based on the Stage-Gate tool and the TRL scale; (iii) use of the Analytic Hierarchy Process (AHP) method in two moments, the first to define the weights of the criteria for validation of the quality of performance indicators related to RD(and)I projects; and the second to assign weights to the evaluation criteria for the mentioned projects at decision gates; (iv) use of the TOPSIS method to validate the quality of the performance indicators; and (v) application of the proposed model, focusing on an RD(and)I project underway at the Army Technological Center (CTEx), aiming to show its potential for replicability to other RD(and)I projects of CoPS at that Center. The main result is an innovative model for monitoring and evaluating RD(and)I projects of CoPS for the defense area, which can be applied at CTEx and other Science and Technology Institutions seeking excellence in innovation management, particularly when facing the challenges of CoPS development. The results of the empirical study conducted in this organizational context showed that it is possible to use the Stage-Gate tool and the TRL scale in an integrated and effective manner to monitor and evaluate RD(and)I projects of CoPS for the defense area throughout their development.
14

A cost estimation of an industrial scale production of nanocellulose filaments utilizing PBCM and TRL : A case study at RISE Research Institutes of Sweden AB / Kostnadsestimering av produktionen för nanocellulosafilament på industriell skala genom användningen av PBCM och TRL : Fallstudie på RISE Research Institutes of Sweden AB

Zhang, Rui Liang, Rask, Lukas January 2019 (has links)
Producing the strongest bio-based material called nanocellulose, in the form of filaments, has shown to be technically feasible at lab-scale, but the production costs remain unknown. The research has focused on technical feasibility and less on costs, which is a common phenomenon when developing new technologies. Constructing a Process-Based Cost Model (PBCM) can link the technical aspects of a technology to its costs of production. However, the accuracy of such a model might be dependent on the data availability of the technology. In this study, the technology of producing nanocellulose filaments has been evaluated along the scale of Technology Readiness Level (TRL) to understand the maturity of the technology and a PBCM has been constructed to show the economic prerequisites for the production of nanocellulose filaments. The main results indicate that at TRL 4, with parts of TRL 5 fulfilled, parameters such as Capital Expenditures cannot be allocated to unit production cost, only Operational Expenditures. Therefore, the relevant cost elements become material and energy as these constitute the currently available data. The PBCM can thus be used to estimate the production costs of different scenarios while highlighting the areas of future research. In the empirical context of nanocellulose filament production, utilizing deionized water in the production is a more promising option compared to utilizing solvents as the cost of recovering the solvent becomes high. Furthermore, using deionized water also becomes more promising due to the fact that other scenarios have not yet been evaluated experimentally. However, as the technology matures and more data becomes available, the model accuracy will increase as more parameters can be included in the model and the basis increases for decisionmaking regarding techno-economic concerns of the technology. / Produktionen av världens starkaste biobaserade material, nanocellulosa i filamentform, har visat sig vara tekniskt möjligt på labbskala, men produktionskostnaderna är idag okända. Forskning som fokuserar mer på den tekniska genomförbarheten och mindre på produktionskostnader är ett vanligt förekommande fenomen i utveckling av ny teknologi. Genom att konstruera en processbaserad kostnadsmodell (PBCM) kan en teknologis tekniska aspekt länkas till dess produktionskostnader. Dock påverkas en sådan modells noggrannhet av datatillgängligheten för teknologin. I denna studie har teknologin för produktionen av nanocellulosa filament utvärderats längs med Technology Readiness Level (TRL) skalan för att förstå teknologins mognadsgrad. Därefter har en PBCM konstruerats för att visa de ekonomiska förutsättningarna för en produktion av nanocellulosafilamenten på industriell skala. Huvudresultaten indikerar att på TRL 4, med delar av TRL 5 uppfyllda, kan somliga parametrar såsom investeringskostnader inte allokeras till enhetsproduktionskostnaden, utan bara löpande kostnader. De relevanta kostnadselementen blir därför material och energi då dessa utgör den aktuellt tillgängliga datan. PBCM kan därför användas för att beräkna produktionskostnader av olika scenarion och lyfta fram områden för framtida forskning. I den empiriska kontexten av produktionen av nanocellulosafilament är användningen av avjoniserat vatten ett mer lovande alternativ jämfört med användningen av lösningsmedel då kostnaden för återvinningen av lösningsmedlet blir högt. Dessutom är användningen av avjoniserat vatten mer lovande eftersom övriga scenarion inte har testats experimentellt än. Allteftersom teknologin mognar och mer data blir tillgänglig, så kommer modellens noggrannhet öka då fler parametrar kan inkluderas i modellen och därmed kan underlaget öka för beslutsfattning gällande teknoekonomiska frågor om teknologin.
15

Evaluating Innovation Readiness - A Case Study / Utvärdera innovationers mognadsgrad - En fallstudie

Rosén, Josefin January 2018 (has links)
To remain competitive and create a sustainable business, Original Equipment Manufacturers (OEMs) need to develop both incremental and radical innovation. What many companies struggle with is to evaluate the potential of innovation initiatives. The development of products and innovations has over the years changed from a traditional technocentric view into a more human-centered view with the user’s desirability in focus. Also, the increased global competition and interest in business model innovation are forcing companies to verify the viability of the offering to their customers. While Technology Readiness Level (TRL) is an established tool for evaluating the technology, there are no holistic methods which also evaluates the readiness of the users and business.  The purpose of this thesis was to review available theory and methods used for evaluating the potential and readiness of innovation initiatives and to develop a holistic methodology to link the business, user, and technology related innovation activities. The innovation readiness is a combination of business, user, and technology readiness. The study started with a literature study where existing methods were presented from the three aspects; business, user, and technology. Since many critical decisions are made in the front-end of the innovation, the focus in the study has been to identify methods in the early stages of the process. This thesis was performed in collaboration with Company X, a global equipment manufacturer which also was the main object in this study. The findings from a case study performed at Company X were verified by comparing the identified methods and processes used at five external companies. Data was gathered by conducting semi-structured interviews both at Company X and the external companies and finding were compared in a cross-case analysis. In general, the methods used at the OEMs are quite similar, and all manage to balance the three aspects; business, user, and technology.  Based on the findings from the study of the companies and the literature review, a methodology framework is suggested which presents existing evaluating methods from the three aspects business, user, and technology. / För att förbli konkurrenskraftiga och för att skapa en hållbar affärsmodell behöver OEM:s utveckla både inkrementell och radikal innovation. Vad många företag arbetar hårt med är att utvärdera potentialen i innovationsinitiativ. Utvecklingen av produkter och innovationer har genom åren förändrats från en traditionell utveckling med tekniken i centrum till en mer användare-centrerad vy med fokus på användarens intresse av produkten. Dessutom har den ökade globala konkurrensen och intresset för affärsmodellinnovation har ökat intresset hos företagen att verifiera lönsamheten i deras erbjudanden till sina kunder. Medan TRL är ett etablerat verktyg för utvärdering av teknik finns det inga holistiska metoder som även utvärderar användarnas och företagets mognadsgrad och beredskapsnivå. Syftet med detta var att se över tillgänglig teori och metoder för att utvärdera potentialen och mognadsgraden av innovationsinitiativ och att utveckla en holistisk metod för att länka innovations aktiviteter relaterade till affär, användare och teknik. Mognadsgraden av innovation består av en kombination av affärens, användarens och teknikens mognadsgrad. Studien inleddes med en litteraturstudie där befintliga metoder presenterades från de tre aspekterna affär, användare och teknik. Fokus i studien har varit att identifiera metoder i de tidiga stadierna av processen då många kritiska beslut tas i början av innovationsprocessen. Detta examensarbete utfördes i samarbete med Företag X som är en global utrustningstillverkare och som även var huvudobjektet i denna studie. En fallstudie utfördes på Företag X och resultaten från studien verifierades genom att jämföra det med de identifierade metoder och processer som används på fem externa företag. Data samlades in genom att genomföra halvstrukturerade intervjuer både hos Företag X och de externa företagen och resultatet jämfördes i en tvärgående analys. Generellt sätt är metoderna som används hos OEM-tillverkarna ganska lika och alla lyckas balansera de tre aspekterna affär, användare och teknik. Baserat på resultaten från studien av företagen och litteraturundersökningen föreslås en metod som presenterar befintliga utvärderingsmetoder från de tre aspekterna affärer, användare och teknik.
16

Introducing a Framework for Innovation Readiness Levels – A Framework to Evaluate Innovation Efforts / Presentation av innovationsnivåer – Ett ramverk för att mäta mognadsgraden av innovation

Lunner, Carl-Magnus, Worrmann, Emelie January 2018 (has links)
When developing new products, it is important to be able to evaluate their readiness as this helps organizations manage three major challenges of product development, performance, schedule, and budget. The National Aeronautics and Space Administration (NASA) discovered this in 1990 and developed a nine-level framework to measure the progression of technology development, Technology Readiness Levels (TRLs).  The framework has since then been adopted by many different industries, among them OEMs. However, there are more aspects of the innovation process than just technology. Research topics such as user centered design and business model innovation has lately gained much attention, indicating that user and business aspects of the innovation are important. Therefore, the purpose of his thesis was to propose a framework to evaluate the readiness of business, user and technology aspects. To do so, a case study was performed at the Swedish OEM (Original Equipment Manufacturer) Husqvarna Group, a global producer of equipment for garden and park care, as well as for the construction industry. A literature study was performed to create an understanding of the current knowledge on the topic. Semi structured interviews were used to investigate how innovation is performed at the researched company. The result from these interviews was contrasted with the results from interviews at four other Swedish OEMs, to increase external validity. Lastly the findings were validated through focus group interviews at Husqvarna Group. The case study resulted in the identification of important steps when developing viable, desirable, and feasible products. From these, the nine most important for business and user was identified and frameworks for business and user readiness respectively were developed, along with attainment criteria for each level. The findings showed that the TRL framework still holds relevance, however the attainment criteria were adjusted to better suit OEMs. Together these three frameworks create the Innovation Readiness Level (IRL) framework. / Vid utveckling av nya produkter finns det tre stora utmaningar i produktutvecklingen; prestanda, tid och budget, därför är det viktigt att ständig stötta processen genom att utvärdera projektets mognadsgrad. År 1990 utvecklade NASA en niogradig skala som kan tillämpas som ett ramverk för att mäta mognadsgraden av en teknikutveckling, Technology Readiness Levels (TRL), detta har sedan dess införts av många industriföretag. När det kommer till innovation finns det dock fler aspekter än enbart teknik att ta hänsyn till. Forskning inom användarfokuserad design och affärsmodellsinnovation har fått ökad uppmärksamhet den senaste tiden, vilket indikerar att användare och affär är viktiga aspekter inom innovation. Syftet med denna studie är att föreslå ett ramverk för att utvärdera mognadsgraden utifrån ett affärs-, användar- och teknikperspektiv. För att genomföra detta gjordes en fallstudie på det svenska industriföretaget Husqvarna Group, en global tillverkare av skogs-, park- och trädgårdsprodukter samt utrustning för konstruktionsindustrin. För att skapa en förståelse av den befintliga kunskapen inom ämnet gjordes en bred litteraturstudie. Semi-strukturerade intervjuer genomfördes för att undersöka hur innovation hanteras inom Husqvarna Group. Resultatet från det undersökta företaget ställdes i kontrast med intervjuresultat från fyra andra svenska industriföretag för att skapa ett mer generaliserbart resultat. Till sist testades resultatet genom validering med fokusgruppsintervjuer på Husqvarna Group.  Fallstudien resulterade i identifiering av betydelsefulla steg vid utveckling av en ny produkt som ordnades kronologiskt. Vid varje nivå i skalan föreslogs en rad kriterier från ett affärs- respektive användarperspektiv som ett produktutvecklingsprojekt bör uppnå för att öka chansen att bli väl mottagen när den når marknaden. Resultatet visade även att TRL-ramverket fortfarande är aktuellt och relevant, men uppnåendekriterier anpassades för ett industriföretag. Tillsammans skapar dessa tre faktorer det föreslagna ramverket Innovation Readiness Levels (IRL).
17

Low Loss Substrate Integrated Waveguide N-way Power Divider

Mohammadi, Pejman 01 January 2013 (has links) (PDF)
Substrate Integrated Waveguide (SIW) technology has been used in designing and fabricating SIW n-way power dividers. In this thesis employing this technology three-port and
18

Low impedance characterisation and modeling of high power LDMOS devices

Malan, Pieter Jacob De Villiers 12 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2005. / In RF power transistor characterisation, the designer is confronted with low impedance measurements (typically from 1 Ohm to 12 Ohm). These transistors are contained in metal-ceramic packages of which the lead widths vary with power capability. This thesis presents a high-quality fixture design with low impedance TRL calibration standards for characterisation of an LDMOS transistor. Pre-matching networks are used to transform to the low impedance environment. Since these pre-matching networks are independent of the termination impedance, the low impedance port can always be designed to comply with the same dimension as the device which is being measured.
19

Evaluating Inductive Electric Road Systems Implementation : A multiple case study in Sweden

Nagarasan, Yuvanesh, Francis Xavier, Kevin Raja January 2020 (has links)
Sustainable transportation solutions are the goal for the future. With the technological shit happening in the transportation market towards electric vehicles, the electric road system (ERS) is a necessary technology required to reach the sustainability goals for the future. While many studies show the role of innovation in a socio-technical landscape, many neglect the diffusion process of the innovation which occurs to create a socio-technical change. The nature of this thesis is an exploratory case study with a qualitative approach. To address the study, a literature review for the diffusion of innovation, its characteristics, multi-level perspective, and technology readiness level (TRL) was presented in order to provide a better understanding and build a foundation for the research. A review of scientific articles regarding the electric road system was performed to provide insights and obtain information on the technology. The data from scientific articles were complemented by interviews from experts regarding electric road systems to obtain an understanding of technology if it was to be implemented in the future in Sweden. The empirics collected were analyzed using the literature framework and conclusions were drawn. Analyzing the data was required to find the factors hindering the technology and if there is a window of opportunity for the technology to exist in the Swedish market. Environmental sustainability has been the driving factor, but the rate of diffusion for the technology will depend on the complexity and the maturity of the technology to function as a whole working system. The study contributes to evaluating the implementation of an inductive electric road system in the Swedish context and if it could be a viable solution in the transportation market. The perspectives of the technology in the Swedish market and the motivation for the solution are discussed. An analytical contribution by evaluating if the technology could exist in the future and insights on the diffusion of the technology into the existing landscape.
20

Efficient analysis and design of devices in Substrate Integrated Waveguide (SIW) technology

Díaz Caballero, Elena 20 December 2013 (has links)
Para abordar el análisis de estas estructuras de forma altamente eficiente, se pretenden utilizar dos enfoques distintos, que llevarían a dos técnicas distintas y eficientes, pero cada una de ellas con sus ventajas e inconvenientes respecto de la otra, que podremos concluir una vez finalizado el trabajo de investigación. Por un lado, se pretende utilizar el Método de los Momentos, una técnica numérica que convierte las ecuaciones integrales de un problema electromagnético en un sistema linear, expandiendo la magnitud desconocida usando un conjunto de funciones con coeficientes desconocidos. Al forzar las condiciones de contorno, en este caso de potencial eléctrico, en un determinado número de puntos, se obtiene un sistema linear de ecuaciones que será resuelto numéricamente. Por otro lado, según el segundo enfoque, pretende utilizar una expansión en modos cilíndricos del campo, tanto incidente como dispersado. Dada la geometría circular de las vías éstas pueden ser caracterizadas de forma analítica mediante espectros circulares. Posteriormente se resolverá el acoplo entre las vías mediante el método de [1] pero generalizado al caso de objetos inmersos en un medio dieléctrico infinito, y se desarrollará un nuevo método de acoplo modal entre modos cilíndricos y modos guiados proyectando las ecuaciones del acoplo modal tanto sobre modos cilíndricos como sobre modos guiados para evitar las singularidades que aparecen con el método de de [2] cuando los planos de referencia están muy próximos al objeto dispersor. Por tanto, esta técnica caracterizará las vías de forma analítica y resolverá las integrales del acoplo de modos mediante la transformada rápida de Fourier. Para aumentar más aún la eficiencia de ambos métodos se evitará repetir los cálculos para cada punto en frecuencia, y se implementará la técnica de barrido rápido en frecuencia similar descrita en [3], adaptándola al caso particular de cada método de análisis, aunque se prevé que quizá dicho procedimiento sea más difícil de implementar en el segundo método. Se espera que ambas técnicas puedan proporcionar unos tiempos de computación inferiores a los del software comercial de análisis electromagnético más habitual (i.e. HFSS), y también inferiores a otros métodos de análisis recientemente aparecidos en la bibliografía técnica ([4],[5],[6]). En concreto, se espera que los tiempos de computación para barrido discreto en frecuencia sea inferior con el segundo método ya que usa únicamente expresiones analíticas y transformada rápida de Fourier, pero, dado que el primer método es más susceptible de realizar barrido rápido en frecuencia, éste puede ser muy útil a la hora de realizar muchos análisis consecutivos. Una vez se disponga de métodos eficientes para el análisis de dispositivos SIW, se abordará el diseño de varios dispositivos pasivos en esta tecnología (filtros de diferentes topologías, diplexores, multiplexores, híbridos, acopladores, etc.). Como se dispone de una vasta experiencia en el grupo de investigación en el diseño de dispositivos en guía de onda rectangular, se puede como primera aproximación realizar el diseño en guía, y luego transformar esta estructura guiada en otra en tecnología SIW mediante unas reglas empíricas que relacionan ambas tecnologías [7]. Posteriormente se debe ajustar el diseño en el dispositivo SIW ya que estas reglas empíricas no consiguen que la respuesta sea idéntica a la del dispositivo guiado original, principalmente debido al hecho de que los irises rectangulares de la guía son transformados en vías metalizadas con geometría circular, no rectangular. Para minimizar este ajuste, se diseñará el dispositivo guiado con irises con esquinas redondeadas en la cavidad (método de [8] pero con un simulador más eficiente [9]), haciendo que el radio de esas esquinas redondeadas coincida con el de las vías metalizadas que se van a utilizar en el dispositivo SIW. Esto permitirá [...] (Ver documento anexo) / Díaz Caballero, E. (2013). Efficient analysis and design of devices in Substrate Integrated Waveguide (SIW) technology [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34627 / TESIS

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