[pt] Este estudo fornece uma análise da relação entre as práticas da economia circular (EC) e o desempenho nas pequenas e médias empresas (PME) na Europa, seguindo uma abordagem multinível. O projeto de pesquisa descreve as etapas envolvidas para atingir esse objetivo. A primeira etapa (artigo 1) examina as tendências da pesquisa existente. Verificamos as variáveis utilizadas, o tipo de dados, o método de análise, o tipo de indústria, o porte da empresa, o tamanho da amostra e o tema ao qual o artigo pertence. Os resultados indicam que não existe um consenso claro sobre a melhor forma de medir e operacionalizar as práticas de EC e o desempenho das empresas, no entanto as variáveis identificadas podem ser utilizadas como guia para futuras pesquisas sobre EC e o desempenho das empresas. Na segunda etapa (artigo 2), investigamos como os indicadores de desempenho econômico, social e ambiental do país PME moderam a relação entre as práticas de EC e o desempenho da empresa. Em resumo, os resultados apoiam que o impacto financeiro da adoção da EC é positivo e é afetado pelo nível de desempenho nacional econômico e ambiental. A terceira etapa (artigo 3) tem como objetivo desenvolver e testar o modelo empírico que inclui moderação por nível meso. Examinamos a função dos intermediarios no envolvimento das PME nas atividades de EC bem como a presença de Redes de Simbiose Industrial (ISN) afeta o desempenho das PME. As conclusões afirmam que as ISN s podem impulsionar a adopção da EC e os intermediários podem ajudar as PME a superar os obstáculos da EC. / [en] This study provides an examination of the relationship between circular economy (CE) practices and firm performance in small and medium-sized enterprises (SMEs) in Europe, following a multi-level approach. The research project outlines the stages involved to reach this goal. The first stage (paper 1) examines the trends in the existing research. We verified the variables used, the type of data, the method of analysis, the type of industry, the size of the company, the size of the sample and the topic to which the article belongs. The results indicate that there is no clear consensus on the best way to measure and operationalize CE practices and firm performance, however the variables identified can be used as a guide for future research on CE and firm performance. The second stage (paper 2) we investigate how the economic, social, and environmental performance indicators of the SME country moderates the relationship between CE practices and firm performance. In summary, the results support that the financial impact of adopting CE is positive, and it is affected by the level of national economic and environmental performance. The third stage (paper 3) the aim is develop and test empirical model include moderation by meso-level. We examined the function of intermediaries in involving SMEs in CE activities, and how the presence of Industrial Symbiosis Networks (ISN) affects SMEs performance. The findings affirm that ISNs can boost CE adoption and intermediaries can assist SMEs in surmounting CE obstacles.

The increasing shift towards more electric or all electric aircraft urgently necessitates dc/ac converter systems with high power density. Silicon Carbide (SiC) devices, known for their superior performance over traditional silicon-based devices, facilitate this increase in power density. Nonetheless, achieving optimal power density faces challenges due to the unique requirements and conditions of aircraft applications. A primary obstacle is optimizing the topology and parameters of the dc/ac converter system to achieve high power density while adhering to the stringent aerospace EMI standard DO-160 and bearing current limitations. Electric aircraft demand unmatched reliability, necessitating strict control over EMI noise and bearing currents. These considerations significantly impact the selection of topology and parameters to maximize power density. This dissertation assesses how dc voltage, topology, and switching frequency affect component weight, seeking an optimal mix to enhance power density. The methodology and conclusions are validated through a 200-kW motor drive system designed for electric aircraft. Moreover, traditional dc/ac systems are burdened by the weight and space occupied by separate current sensors and short-circuit protection circuits. This work introduces two innovative current sensors that integrate device current sampling with the functionality of traditional shunt resistors, AC hall sensors, and short-circuit protection circuits, thus improving system density and bandwidth. The first sensor, a PCB-based Rogowski coil, integrates with the gate driver and commutation loops, enhancing power density despite challenges in managing CM noise. The second sensor utilizes parasitic inductance in the power loop, with an integrator circuit and an adaptive compensation algorithm correcting errors from parasitic resistance, ensuring high bandwidth accuracy without needing parasitic resistance information. Variable operation conditions from motors pose another challenge, potentially leading to oversized inverters due to uneven loss distribution among switching devices, exacerbated at extreme operating points like motor start-up. This dissertation investigates the loss distribution in multi-level T-Type neutral point clamped (NPC) topology and proposes a novel loss-balance modulation scheme. This scheme ensures even loss distribution across switches, independent of power factor and modulation index, and is applicable to T-type inverters of any level count. Finally, thermal management and insulation at high altitudes present significant challenges. While power devices may be cooled using conventional liquid cooling solutions, components like AC and EMI filters struggle with complex geometries that can create hot spots or high E-field points, complicating filter design for high current applications. A comprehensive design and optimization methodology based on planar heavy-copper PCB design is proposed. By utilizing flexible 2D or 3D E-field shaping and maximizing thermal transfer from copper to ambient, this methodology significantly improves power density and ensures effective heat dissipation and insulation at altitudes up to 50,000 feet. / Doctor of Philosophy / The increasing shift towards more electric or all electric aircraft urgently necessitates dc/ac converter systems with high power density. Silicon Carbide (SiC) devices, known for their superior performance over traditional silicon-based devices, facilitate this increase in power density. Nonetheless, achieving optimal power density faces challenges due to the unique requirements and conditions of aircraft applications. A primary obstacle is optimizing the topology and parameters of the dc/ac converter system to achieve high power density while adhering to the stringent aerospace EMI standard DO-160 and bearing current limitations. Electric aircraft demand unmatched reliability, necessitating strict control over EMI noise and bearing currents. These considerations significantly impact the selection of topology and parameters to maximize power density. This dissertation assesses how dc voltage, topology, and switching frequency affect component weight, seeking an optimal mix to enhance power density. The methodology and conclusions are validated through a 200-kW motor drive system designed for electric aircraft. Moreover, traditional dc/ac systems are burdened by the weight and space occupied by separate current sensors and short-circuit protection circuits. This work introduces two innovative current sensors that integrate device current sampling with the functionality of traditional shunt resistors, AC hall sensors, and short-circuit protection circuits, thus improving system density and bandwidth. The first sensor, a PCB-based Rogowski coil, integrates with the gate driver and commutation loops, enhancing power density despite challenges in managing CM noise. The second sensor utilizes parasitic inductance in the power loop, with an integrator circuit and an adaptive compensation algorithm correcting errors from parasitic resistance, ensuring high bandwidth accuracy without needing parasitic resistance information. Variable operation conditions from motors pose another challenge, potentially leading to oversized inverters due to uneven loss distribution among switching devices, exacerbated at extreme operating points like motor start-up. This dissertation investigates the loss distribution in multi-level T-Type neutral point clamped (NPC) topology and proposes a novel loss-balance modulation scheme. This scheme ensures even loss distribution across switches, independent of power factor and modulation index, and is applicable to T-type inverters of any level count. Finally, thermal management and insulation at high altitudes present significant challenges. While power devices may be cooled using conventional liquid cooling solutions, components like AC and EMI filters struggle with complex geometries that can create hot spots or high E-field points, complicating filter design for high current applications. A comprehensive design and optimization methodology based on planar heavy-copper PCB design is proposed. By utilizing flexible 2D or 3D E-field shaping and maximizing thermal transfer from copper to ambient, this methodology significantly improves power density and ensures effective heat dissipation and insulation at altitudes up to 50,000 feet.

In the last decade, the landscape of storage hardware and software has changed considerably. Storage hardware has diversified from hard disk drives and solid state drives to include persistent memory (PMEM) devices such as phase change memory (PCM) and Flash-backed DRAM. On the software side, the increasing adoption of cloud services for building and deploying consumer and enterprise applications is driving the use of cloud storage services. Cloud providers have responded by providing a plethora of choices of storage services, each of which have unique performance characteristics and pricing. We argue this variety represents an opportunity for modern storage systems, and it can be leveraged to improve operational costs of the systems. We propose that storage tiering is an effective technique for balancing operational or de- ployment costs and performance in such modern storage systems. We demonstrate this via three key techniques. First, THMCache, which leverages tiering to conserve the lifetime of PMEM devices, hence saving hardware upgrade costs. Second, CAST, which leverages tiering between multiple types of cloud storage to deliver higher utility (i.e. performance per unit of cost) for cloud tenants. Third, we propose a dynamic pricing scheme for cloud storage services, which leverages tiering to increase the cloud provider's profit or offset their management costs. / Master of Science / Storage and retrival of data is one of the key functions of any computer system. Improvements in hardware and software related to data storage can help computer users store (a) store the data faster, which makes for overall faster performance; and (b) increase the storage capacity, which helps store the increasing amount of data generated by modern computer users. Typically, most computers are equipped with either a hard disk drive (HDD) or, the newer and faster, solid state drive (SSD) for data storage. In the last decade however, the landscape of data storage hardware and software has advanced considerably. On the hardware side, several hardware makers are introducing persistent memory (PMEM) devices, which provide very high speed, high capacity storage at reasonable price points. On the software side, the increasing adoption of cloud services by software developers that are building and operating consumer and enterprise applications is driving the use of cloud storage services. These services allow the developers to store a large amount of data without having to manage any physical hardware, paying for the service on a usage-based pricing structure. However, every application’s speed and capacity needs are not the same; hence, cloud service providers have responded by providing a plethora of choices of storage services, each of which have unique performance characteristics and pricing. We argue this variety represents an opportunity for modern storage systems, and it can be leveraged to improve the operating costs of the systems. Storage tiering is a classical technique that involves partitioning the stored data and placing each partition in a different storage device. This lets the applications use mulitple devices at once, taking advantage of each’s sterngths and mitigating their weaknesses. We propose that storage tiering is a relevant and effective technique for balancing operational or deployment costs and performance in modern storage systems such as PMEM devices and cloud storage services. We demonstrate this via three key techniques. First, THMCACHE, which leverages tiering between multiple types of storage hardware to conserve the lifetime of PMEM devices, hence saving hardware upgrade costs. Second, CAST, which leverages tiering between multiple types of cloud storage services to deliver higher utility (i.e. performance per unit of cost) for software developers using these services. Third, we propose a dynamic pricing scheme for cloud storage services, which leverages tiering between multiple cloud storage services to increase the cloud service provider’s profit or offset their management costs.

[ES] Con la globalización de los mercados y el aumento de la competitividad, la coordinación se ha convertido en un punto estratégico en la gestión de la cadena de suministro. De hecho, cada actor de la cadena de suministro ya no debe tomar decisiones sin considerar todos los eslabones, sean proveedores, proveedores de proveedores o clientes y estos internos o externos a la organización. Las cadenas de suministro son cada vez más complejas y distribuidas, compuestas por múltiples organizaciones con diferentes objetivos y políticas. La coordinación se puede lograr utilizando uno de estos dos enfoques para la toma de decisiones coordinadas: centralizada o descentralizada con un mecanismo de coordinación. Pero, las empresas son reacias a compartir información, ya sea por la confidencialidad de los datos o porque los modelos centralizados resultantes son de gran complejidad que dificultan su manejo y actualización. Además, aquellas empresas que buscan tomar decisiones en tiempo real requieren de modelos ligeros y ágiles, que, con toda la información local y coordinada con el resto, permitan tomar decisiones rápidas. Las empresas interesadas en la coordinación descentralizada con un mecanismo de coordinación esperan obtener mejores resultados con respecto a la no coordinación, aunque deberían asumir tener peores resultados que con la coordinación centralizada. Para ello en esta tesis, se han estudiado los distintos mecanismos de coordinación para la toma de decisiones descentralizada, dentro de un entorno del procedimiento de horizontes rodantes y con herramienta de planificación y programación de las operaciones basada en el concepto de stroke, que extiende el concepto de lista de materiales más allá de las estructuras tradicionales. Estos permiten desarrollar la formulación de la programación matemática y los mecanismos de coordinación necesarios para resolver los problemas de planificación de operaciones. Esta tesis se presenta como una secuencia de capítulos, con el objeto de analizar y presentar la propuesta de mecanismo de coordinación distribuido con unos recursos compartidos. Los distintos capítulos han servido de base para la preparación de artículos científicos. Estos artículos han sido presentados en congresos de la materia y remitidos a revistas científicas. / [CA] Amb la globalització dels mercats i l'augment de la competitivitat, la coordinació s'ha convertit en un punt estratègic en la gestió de la cadena de subministrament. De fet, cada actor de la cadena de subministrament ja no ha de prendre decisions sense considerar totes les baules, siguen proveïdors, sub-proveïdors o clients i aquests interns o externs a l'organització. Les cadenes de subministrament són cada vegada més complexes i distribuïdes, compostes per múltiples organitzacions amb diferents objectius i polítiques. La coordinació es pot aconseguir utilitzant un d'aquests dos enfocaments per a la presa de decisions coordinades: centralitzat o descentralitzat amb un mecanisme de coordinació. Però, les empreses són poc inclinades a compartir informació, ja siga per la confidencialitat de les dades o perquè els models centralitzats resultants són de gran complexitat que dificulten el seu maneig i actualització. A més, aquelles empresa que busquen prendre decisions en temps real requereixen de models lleugers i àgils, que, amb tota la informació local i coordinada amb la resta, permeten prendre decisions ràpides. Les empreses interessades en la coordinació descentralitzada amb un mecanisme de coordinació esperen obtindre millors resultats respecte de la no coordinació encara que haurien d'assumir tindre pitjors resultats que amb la coordinació centralitzada. Per a això en aquesta tesi, s'han estudiat els diferents mecanismes de coordinació per a la presa de decisions descentralitzada, dins d'un entorn d'horitzons rodant i amb eines de planificació i programació de les operacions basada en el concepte de stroke, que estén el concepte de llista de materials més enllà de les estructures tradicionals. Aquests permeten desenvolupar la formulació de la programació matemàtica i els mecanismes de coordinació necessaris per a resoldre els problemes de planificació d'operacions. Aquesta tesi es presenta com una seqüència de capítols, a fi d'analitzar i presentar la proposta de mecanisme de coordinació distribuït amb uns recursos compartits. Els diferents capítols han servit de base per a la preparació d'articles científics. Aquests articles han sigut presentats en congressos de la matèria i remesos a revistes científiques. / [EN] With the globalization of markets and the increase of competitiveness, coordination has become a strategic point in the management of the supply chain. In fact, each actor in the supply chain must no longer make decisions without considering all the links, whether suppliers, sub-suppliers or customers and those internal or external to the organization. Supply chains are increasingly complex and distributed, composed of multiple organizations with different objectives and policies. Coordination can be achieved using one of these two approaches to coordinate decision making: centralized or decentralized with a coordination mechanism. However, companies are reluctant to share information, either because of the confidentiality of the data or because the resulting centralized models are of great complexity that make their management and update them. In addition, those companies that seek to make decisions in real time require lightweight and agile models, which, with all the local information and coordinated with the rest, allow quick decisions. Companies interested in decentralized coordination with a coordination mechanism expect to obtain better results regarding non-coordination although they should assume to have worse results than with centralized coordination. To this end, in this thesis, the different coordination mechanisms for decentralized decision making have been studied, within an environment of rolling horizons and with tools for planning and scheduling operations based on the concept of stroke, which extends the concept of list of materials beyond traditional structures. These allow to develop the formulation of the mathematical programming and the coordination mechanisms necessary to solve the operations planning problems. This thesis is presented as a sequence of chapters, in order to analyse and present the proposal of distributed coordination mechanism with shared resources. The different chapters have served as the basis for the preparation of scientific articles. These articles have been presented at congresses of the subject and submitted to scientific journals. / Rius Sorolla, GV. (2019). Modelos y Algoritmos de Coordinación para la Planificación de Operaciones basadas en el concepto Stroke en Redes de Suministro distribuidas y con alternativas [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/134017

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In this dissertation, we introduce a novel text representation method mainly used for text classification purpose. The presented representation method is initially based on a variety of closeness relationships between pairs of words in text passages within the entire corpus. This representation is then used as the basis for our multi-level lightweight ontological representation method (TOR-FUSE), in which documents are represented based on their contexts and the goal of the learning task. The method is unlike the traditional representation methods, in which all the documents are represented solely based on the constituent words of the documents, and are totally isolated from the goal that they are represented for. We believe choosing the correct granularity of representation features is an important aspect of text classification. Interpreting data in a more general dimensional space, with fewer dimensions, can convey more discriminative knowledge and decrease the level of learning perplexity. The multi-level model allows data interpretation in a more conceptual space, rather than only containing scattered words occurring in texts. It aims to perform the extraction of the knowledge tailored for the classification task by automatic creation of a lightweight ontological hierarchy of representations. In the last step, we will train a tailored ensemble learner over a stack of representations at different conceptual granularities. The final result is a mapping and a weighting of the targeted concept of the original learning task, over a stack of representations and granular conceptual elements of its different levels (hierarchical mapping instead of linear mapping over a vector). Finally the entire algorithm is applied to a variety of general text classification tasks, and the performance is evaluated in comparison with well-known algorithms.

La thèse comporte trois essais en microéconomie appliquée. En utilisant des modèles d’apprentissage (learning) et d’externalité de réseau, elle étudie le comportement des agents économiques dans différentes situations. Le premier essai de la thèse se penche sur la question de l’utilisation des ressources naturelles en situation d’incertitude et d’apprentissage (learning). Plusieurs auteurs ont abordé le sujet, mais ici, nous étudions un modèle d’apprentissage dans lequel les agents qui consomment la ressource ne formulent pas les mêmes croyances a priori. Le deuxième essai aborde le problème générique auquel fait face, par exemple, un fonds de recherche désirant choisir les meilleurs parmi plusieurs chercheurs de différentes générations et de différentes expériences. Le troisième essai étudie un modèle particulier d’organisation d’entreprise dénommé le marketing multiniveau (multi-level marketing). Le premier chapitre est intitulé "Renewable Resource Consumption in a Learning Environment with Heterogeneous beliefs". Nous y avons utilisé un modèle d’apprentissage avec croyances hétérogènes pour étudier l’exploitation d’une ressource naturelle en situation d’incertitude. Il faut distinguer ici deux types d’apprentissage : le adaptive learning et le learning proprement dit. Ces deux termes ont été empruntés à Koulovatianos et al (2009). Nous avons montré que, en comparaison avec le adaptive learning, le learning a un impact négatif sur la consommation totale par tous les exploitants de la ressource. Mais individuellement certains exploitants peuvent consommer plus la ressource en learning qu’en adaptive learning. En effet, en learning, les consommateurs font face à deux types d’incitations à ne pas consommer la ressource (et donc à investir) : l’incitation propre qui a toujours un effet négatif sur la consommation de la ressource et l’incitation hétérogène dont l’effet peut être positif ou négatif. L’effet global du learning sur la consommation individuelle dépend donc du signe et de l’ampleur de l’incitation hétérogène. Par ailleurs, en utilisant les variations absolues et relatives de la consommation suite à un changement des croyances, il ressort que les exploitants ont tendance à converger vers une décision commune. Le second chapitre est intitulé "A Perpetual Search for Talent across Overlapping Generations". Avec un modèle dynamique à générations imbriquées, nous avons étudié iv comment un Fonds de recherche devra procéder pour sélectionner les meilleurs chercheurs à financer. Les chercheurs n’ont pas la même "ancienneté" dans l’activité de recherche. Pour une décision optimale, le Fonds de recherche doit se baser à la fois sur l’ancienneté et les travaux passés des chercheurs ayant soumis une demande de subvention de recherche. Il doit être plus favorable aux jeunes chercheurs quant aux exigences à satisfaire pour être financé. Ce travail est également une contribution à l’analyse des Bandit Problems. Ici, au lieu de tenter de calculer un indice, nous proposons de classer et d’éliminer progressivement les chercheurs en les comparant deux à deux. Le troisième chapitre est intitulé "Paradox about the Multi-Level Marketing (MLM)". Depuis quelques décennies, on rencontre de plus en plus une forme particulière d’entreprises dans lesquelles le produit est commercialisé par le biais de distributeurs. Chaque distributeur peut vendre le produit et/ou recruter d’autres distributeurs pour l’entreprise. Il réalise des profits sur ses propres ventes et reçoit aussi des commissions sur la vente des distributeurs qu’il aura recrutés. Il s’agit du marketing multi-niveau (multi-level marketing, MLM). La structure de ces types d’entreprise est souvent qualifiée par certaines critiques de système pyramidal, d’escroquerie et donc insoutenable. Mais les promoteurs des marketing multi-niveau rejettent ces allégations en avançant que le but des MLMs est de vendre et non de recruter. Les gains et les règles de jeu sont tels que les distributeurs ont plus incitation à vendre le produit qu’à recruter. Toutefois, si cette argumentation des promoteurs de MLMs est valide, un paradoxe apparaît. Pourquoi un distributeur qui désire vraiment vendre le produit et réaliser un gain recruterait-il d’autres individus qui viendront opérer sur le même marché que lui? Comment comprendre le fait qu’un agent puisse recruter des personnes qui pourraient devenir ses concurrents, alors qu’il est déjà établi que tout entrepreneur évite et même combat la concurrence. C’est à ce type de question que s’intéresse ce chapitre. Pour expliquer ce paradoxe, nous avons utilisé la structure intrinsèque des organisations MLM. En réalité, pour être capable de bien vendre, le distributeur devra recruter. Les commissions perçues avec le recrutement donnent un pouvoir de vente en ce sens qu’elles permettent au recruteur d’être capable de proposer un prix compétitif pour le produit qu’il désire vendre. Par ailleurs, les MLMs ont une structure semblable à celle des multi-sided markets au sens de Rochet et Tirole (2003, 2006) et Weyl (2010). Le recrutement a un effet externe sur la vente et la vente a un effet externe sur le recrutement, et tout cela est géré par le promoteur de l’organisation. Ainsi, si le promoteur ne tient pas compte de ces externalités dans la fixation des différentes commissions, les agents peuvent se tourner plus ou moins vers le recrutement. / This thesis includes three essays in applied microeconomics. Using learning and network effects models, we study agents’ behavior in various environments through three chapters. The first chapter examines natural resource exploitation under uncertainty with learning and heterogeneous priors. In the second chapter, we examine the problem of research Foundation concerned with finding good quality researchers for today and the future. The third chapter studies the Multi-level marketing organizations. The first chapter is entitled "Renewable Resource Consumption in a Learning Environment with Heterogeneous beliefs". This work uses a learning model with heterogeneity of beliefs to study natural resources consumption under uncertainty. Following Koulovatianos et al (2009), we distinguish two types of learning process: adaptive learning and learning. I find that learning decreases the total consumption of the resource in comparison with adaptive learning. However, individually and under some conditions, some exploiters could consume more in learning than in adaptive learning. In learning, the exploiter faces two kinds of incentive to invest in the resource: self-incentive which is always positive and heterogeneity incentive which may be negative. The effect of learning on individual consumption depends on the sign and the extent of the heterogeneity incentive. Using absolute change and relative change of consumption due to a change in beliefs, we find that the exploiters tend to converge to a common behaviour. The second chapter is entitled "A perpetual Search for Talent across Overlapping Generations". We use a dynamic discrete time model with overlapping generations to study how a research Fund should optimally rank and select which researchers to give a grant. The optimal decision rule depends on both the perceived quality of researchers based on past success histories and on age. Between two researchers of equal perceived qualities the Fund should select the youngest. This work contributes to the understanding of the bandit problems sometime known to be untractable and pspace-hard. Here, instead of looking for an index characterization, we propose to rank or eliminate progressively the researchers by comparing them two by two. The third chapter is entitled "Paradox about the Multi-Level Marketing". Over the past 50 years, the Multi-level Marketing (MLM) has become an important business strategy. vi MLM is a marketing method in which independent distributors of a product get profits not only from their own sales, but also from recruiting other distributors. According to the promoters of this organization, the purpose of the business and the will of the distributors are to sell the product and not to set up a scam. The question is the following: if the real intention is to sell, why does a distributor recruit other distributors who will become his competitors? It is well known in classical industrial organization that people avoid competition as well as possible. Why is it not the case in the MLM organization? We explain this paradox by the particular economic structure of the MLM. Distributor could not sell enough if he did not recruit. Recruiting provides a price leading power and allows to sell more and make more profit (in some respect). Moreover, the MLM is similar to the multi-sided market structure a la Rochet and Tirole (2003, 2006) and Weyl (2010). There is network effect between recruitment and selling activity. Thus, the extent of the paradox can also be explained by the different commissions set by the MLM promoters.

A travers l'observation des services publics de base, cette thèse s'intéresse à la réorganisation des pouvoirs politiques et techniques consécutive à la mise en place de la réforme de décentralisation. En Inde, cette question a déjà fait l'objet de plusieurs études de cas en zone rurales et dans les villes métropolitaines. L'objet de ce travail est de compléter ce corpus en le replaçant dans le contexte différencié des petites villes indiennes. Celles-ci ont jusqu'ici peu interpellé l'attention des chercheurs et des planificateurs. Ce désintérêt traduit un biais dans la manière de penser l'urbanisation indienne où la « ville » désigne avant tout des agglomérations métropolitaines, considérées comme les moteurs de la croissance économique, aux dépens du reste de l'Inde urbaine. Pourtant, une part importante de la population urbaine vit aujourd'hui dans ce type de villes et est donc tout autant concernée par les changements introduits par les nouvelles politiques urbaines issues de la décentralisation. Dans le cadre de ce travail doctoral, une enquête a été menée à travers quatre petites villes de 20000 habitants sélectionnées à l'est de l'Uttar Pradesh en interrogeant les hommes politiques, les ingénieurs et les habitants. La recherche empirique s'est appliquée à analyser la formation des gouvernements locaux avec une perspective multi-niveaux pour comprendre les transformations institutionnelles depuis la réforme. Les résultats de l'étude permettent d'obtenir une image du processus d'émergence des municipalités dans les petites villes / This Ph.D research aims to analyse the new political and technical arrangements in small towns governance, especially regarding the management of publics basic services, since decentralisation reforms in India. Various research projects have dealt with these subjects in rural areas and large metropolises but little attention has been paid to the same issues in smaller urban settlements. Yet more than half of the urban population in India lives in these towns. There has been a bias within Indian urban studies against small towns, because the idea of “urban” has always designated large urban settlements. This scientific disinterest translates into a more characteristic way of thinking about the urbanization process and resource allocation in India where big cities have been glorified as part of “Shining India”, while at the same time forgetting the rest of urban India. For this thesis, a sample survey has been conducted in a few selected towns comprising around 20,000 inhabitants in eastern Uttar Pradesh. The fieldwork has focused on urban local bodies and interviews has been conducted conducted with political leaders, government officials appointed at different levels (local, regional and state) and other actors such as engineers. Other interviews have been conducted with citizens as users to verify the information collected on effective service delivery and to understand what their relationships are with elected public servants and service providers. The results of the study gives a good view of the institutional building process consequent to decentralisation reform and the municipality emergence in small towns

Les conditionneurs alternatifs – continu à absorption sinusoïdale (PFC) pour les applications critiques se distinguent par un haut niveau de performances tel que les THD réduits, un haut rendement et une bonne fiabilité. Leur importance est d’autant plus nécessaire qu’une continuité de service des alimentations est requise même en présence d’une défaillance interne de composant. Deux types de structures associées à leur commande sont réalisés à cet effet, les structures à redondance parallèle et les structure à redondance en série. Elles consistent respectivement en l’ajout d’un bras d’interrupteur dans le cas de la redondance parallèle, qui est une option plus compliquée et en une suppression d’une cellule de commutation dans le deuxième cas. L’étude présentée ici, consiste en premier lieu en une exploration et une évaluation de nouvelles familles de topologies multi-niveaux, caractérisée par un partitionnement cellulaire en série. Ces nouvelles topologies, ainsi que leurs variantes, comportent au moins une redondance structurelle avec des cellules mono-transistor à défaut de commande non critique et symétriques à point-milieu. Elles sont donc génériques pour la mise en parallèle et l’extension en triphasé. Cependant, elles sont pour la plupart peu compétitives à cause des composants qui sont souvent surdimensionnés et donc plus onéreuses, en comparaison avec la structure PFC Double-Boost 5 Niveaux à composants standards 600 V (brevetée par l’INPT – LAPLACE –CNRS en 2008) que nous étudions. Cette dernière constitue le meilleur compromis entre un bon rendement et une maîtrise des contraintes en mode dégradé. Sur le plan théorique nous montrons que le seul calcul de fiabilité basé uniquement sur un critère de premier défaut est inadapté pour décrire ce type de topologie. La prise en compte de la tolérance de panne est nécessaire et permet d'évaluer la fiabilité globale sur une panne effective (i.e. au second défaut). L'adaptation de modèles théoriques de fiabilité à taux de défaillance constant mais prenant en compte, au niveau de leurs paramètres, le report de contrainte en tension et l'augmentation de température qui résulte d'un premier défaut, permet de chiffrer en valeur relative, le gain obtenu sur un temps court. Ce résultat est compatible avec les systèmes embarqués et la maintenance conditionnelle. Un prototype monophasé de PFC double-boost 5 niveaux à commande entièrement numérique et à MLI optimisée reconfigurable en temps réelle a été réalisé afin de valider l’étude. Il permet une adaptation automatique de la topologie de 5 à 4 puis 3 niveaux par exemple. Ce prototype a également servi de test d'endurance aux transistors CoolMos et diodes SiC volontairement détruits dans des conditions d'énergie maîtrisée et reproductibles. D’autres campagnes d'endurance en modes dégradés ont été réalisées en laboratoire sur plusieurs centaines d’heures en utilisant ce même prototype. Nous nous sommes axés sur la détection de défauts internes et le diagnostic (localisation) rapide, d'une part par la surveillance directe et le seuillage des tensions internes (tensions flottantes) et d'autre part, par la détection d’harmoniques (amplitude et phase) en temps réel. Ces deux techniques ont été intégrées numériquement et évaluées sur le prototype, en particulier la seconde qui ne requiert qu'un seul capteur. Enfin, nous proposons une nouvelle variante PFC expérimentée en fin de mémoire, utilisant deux fois moins de transistors et de drivers pour les mêmes performances fréquentielles au prix d'un rendement et d'une répartition des pertes légèrement moins favorable que la structure brevetée. / This work is an exploration and an evaluation of new variants of multi-level AC/DC topologies (PFC) considering their global reliability and availability: electrical safety with an internal failure and post-failure operation. They are based on a non-differential AC and centre tap connection that led to symmetrical arrangement cells in series. These topologies permit an intrinsic active redundancy between cells in a same group and a segregation capability between the two symmetrical groups of cells. More again, they are modular and they can be paralleled and derived to any number of levels. Only single low-voltage (600V) transistor pear cell is used avoiding the short-circuit risk due to an unwanted control signal. Comparisons, taking into account losses, distribution losses, rating and stresses (overvoltage and over-temperature) during the post-operation are presented. Results highlight the proposed 5-level Double-Boost Flying Capacitor topology. This one was patented at the beginning of thesis, as a solution with the best compromise. On the theoretical side, we show that the reliability calculation based only on a "first fault occurrence" criterion is inadequate to really describe this type of topology. The inclusion of fault tolerance capability is needed to evaluate the overall reliability law (i.e. including a second failure). The adaptation of theoretical models with constant failure rate including overvoltage and over-temperature dependencies exhibit an increasing of the reliability over a short time. This property is an advantage for embedded systems with monitoring condition. Local detection and rapid diagnosis of an internal failure were also examined in this work. Two methods are proposed firstly, by a direct flying caps monitoring and secondly, by a realtime and digital synchronous demodulation of the input sampled voltage at the switching frequency (magnitude and phase). Both techniques have been integrated on FPGA and DSP frame and evaluated on a AC230V-7kW DC800V – 31kHz lab. set-up. We put forward the interest of the second method which only uses one input voltage sensor. Finally, we propose in this dissertation a new generic X-level PFC Vienna using, in 5-level version, half transistors and drivers for identical input frequency and levels. At the cost of a slight increase of losses and density losses, this topology appears very attractive for the future. A preliminary lab. set-up and test were also realized and presented at the end of the thesis.

Sustainable development has become in last two decades a phenomenon. Principles of this concept are implemented into most of political development documents at the international, national, regional and local level. Outcomes of sustainable development assessment are often used as basis of measures which influence the process of spatial development. However there exist many approaches how to assess the sustainable development, so far it haven`t been achieved a general consensus how to do it. The aim of this thesis is a critical interpretation of literature considering sustainable development and analysis of implementation of sustainable development assessment in municipalities of Czech Republic. Method of this analysis is desk research of documents called analysis of spatial sustainable development (rozbor udržitelného rozvoje území), which the municipalities have to (by law) make out and semi-standardized interview with representatives of local and regional authorities