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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.
71

A integração da geração fotovoltaica distribuída à matriz elétrica brasileira: uma análise sob a ótica institucional / The integration of the photovoltaic distributed generation on Brazilian electric matrix: an analysis from the institutional perspective

Pavanelli, João Marcos Mott 19 December 2016 (has links)
A matriz brasileira de energia elétrica foi construída historicamente como resultado da confrontação de interesses econômicos, políticos e sociais. Graças a avanços tecnológicos, o setor elétrico brasileiro passa por uma fase de possível inserção de novos modelos, como a geração distribuída de fontes energéticas alternativas, como eólica, biomassa e solar fotovoltaica. Este trabalho oferece uma análise institucional para a compreensão das possibilidades de inserção da geração distribuída fotovoltaica na rede elétrica. Essa análise institucional foi feita através de uma triangulação de técnicas, partindo de revisão bibliográfica de literatura científica, que gerou um modelo analítico para identificar e classificar os principais marcos históricos que direcionaram a estruturação da matriz energética brasileira. Os dados foram confrontados com as entrevistas em profundidade com especialistas do setor elétrico. Os resultados fundamentaram modelos que descrevem a formação histórica de instituições sob os aspectos econômicos, técnicos e normativos. Além disso, os resultados indicam um cenário favorável para investimentos em geração distribuída fotovoltaica até o final da década de 2020, mas também sugerem um possível conflito de equacionamento de custos entre os geradores distribuídos e as concessionárias de distribuição de energia elétrica / The Brazilian electric matrix was built historically as a result of the confrontation among economic, political and social interests. Given the technological advance, the Brazilians electric sector can introduce new models of electric generation, as the distributed generation from alternative energy sources as wind, biomass and photovoltaics. This study offers an institutional analysis to comprehend the perspectives of introducing distributed generation from photovoltaics on Brazilian electric network. This institutional analysis undertook a triangulation of techniques, starting from a literature review, which supported an analysis model. This model was used to identify and classify the main historic marks that constrained the choices concerning the Brazilians electric matrix composition. Historical data was confronted to in-depth interviews with specialists of the Brazilians electric sector. Results supported models which describe the historic formation of institutions under economic, technical and normative aspects. Furthermore the results indicate a favorable scenario to invest in distributed generation from photovoltaic systems in Brazil, at least until 2020, but they also forecast a possible conflict concerning the balance of some costs between the local energys distributor and the owners of distributed generation systems
72

A integração da geração fotovoltaica distribuída à matriz elétrica brasileira: uma análise sob a ótica institucional / The integration of the photovoltaic distributed generation on Brazilian electric matrix: an analysis from the institutional perspective

João Marcos Mott Pavanelli 19 December 2016 (has links)
A matriz brasileira de energia elétrica foi construída historicamente como resultado da confrontação de interesses econômicos, políticos e sociais. Graças a avanços tecnológicos, o setor elétrico brasileiro passa por uma fase de possível inserção de novos modelos, como a geração distribuída de fontes energéticas alternativas, como eólica, biomassa e solar fotovoltaica. Este trabalho oferece uma análise institucional para a compreensão das possibilidades de inserção da geração distribuída fotovoltaica na rede elétrica. Essa análise institucional foi feita através de uma triangulação de técnicas, partindo de revisão bibliográfica de literatura científica, que gerou um modelo analítico para identificar e classificar os principais marcos históricos que direcionaram a estruturação da matriz energética brasileira. Os dados foram confrontados com as entrevistas em profundidade com especialistas do setor elétrico. Os resultados fundamentaram modelos que descrevem a formação histórica de instituições sob os aspectos econômicos, técnicos e normativos. Além disso, os resultados indicam um cenário favorável para investimentos em geração distribuída fotovoltaica até o final da década de 2020, mas também sugerem um possível conflito de equacionamento de custos entre os geradores distribuídos e as concessionárias de distribuição de energia elétrica / The Brazilian electric matrix was built historically as a result of the confrontation among economic, political and social interests. Given the technological advance, the Brazilians electric sector can introduce new models of electric generation, as the distributed generation from alternative energy sources as wind, biomass and photovoltaics. This study offers an institutional analysis to comprehend the perspectives of introducing distributed generation from photovoltaics on Brazilian electric network. This institutional analysis undertook a triangulation of techniques, starting from a literature review, which supported an analysis model. This model was used to identify and classify the main historic marks that constrained the choices concerning the Brazilians electric matrix composition. Historical data was confronted to in-depth interviews with specialists of the Brazilians electric sector. Results supported models which describe the historic formation of institutions under economic, technical and normative aspects. Furthermore the results indicate a favorable scenario to invest in distributed generation from photovoltaic systems in Brazil, at least until 2020, but they also forecast a possible conflict concerning the balance of some costs between the local energys distributor and the owners of distributed generation systems
73

Invariants topologiques des espaces non-commutatifs. / Topological invariants of non-commutative spaces.

Blanc, Anthony 05 July 2013 (has links)
Dans cette thèse, on donne une définition de la K-théorie topologique des espaces non-commutatifs de Kontsevich (c'est-à-dire des dg-catégories) définis sur les nombres complexes. L'introduction de ce nouvel invariant initie la recherche des invariants de nature topologique des espaces non-commutatifs, comme "simplifications" des invariants algébriques (K-théorie algébrique, homologie cyclique, périodique comme étudiés dans les travaux de Tsygan, Keller). La motivation principale vient de la théorie de Hodge non-commutative au sens de Katzarkov--Kontsevich--Pantev. En géométrie algébrique, la partie rationnelle de la structure de Hodge est donnée par la cohomologie de Betti rationnelle, qui est la cohomologie rationnelle de l'espace des points complexes du schéma. La recherche d'un espace associé à une dg-catégorie trouve une première réponse avec le champ (défini par Toën--Vaquié) classifiant les dg-modules parfaits sur cette dg-catégorie. La définition de la K-théorie topologique a pour ingrédient essentiel le foncteur de réalisation topologique des préfaisceaux en spectres sur le site des schémas de type fini sur les complexes. La partie connective de la K-théorie semi-topologique peut être définie comme la réalisation topologique du champ en monoïdes commutatifs des dg-modules parfaits. Cependant pour atteindre la K-théorie négative, on réalise le préfaisceau donné par la K-théorie algébrique non-connective. Un de nos résultats principaux énonce l'existence d'une équivalence naturelle entre ces deux définitions dans le cas connectif. On montre que la réalisation topologique du préfaisceau de K-théorie algébrique connective pour la dg-catégorie unité donne le spectre de K-théorie topologique usuel. Puis que c'est aussi vrai pour la K-théorie algébrique non-connective, en utilisant la propriété de restriction aux lisses de la réalisation topologique. En outre, cette propriété de restriction aux schémas lisses nécessite de montrer une généralisation de la descente propre cohomologique de Deligne, dans le cadre homotopique non-abélien.La K-théorie topologique est alors définie en localisant par rapport à l'élément de Bott. Cette définition repose donc sur des résultats non-triviaux. On montre alors que le caractère de Chern de la K-théorie algébrique vers l'homologie périodique se factorise par la K-théorie topologique, donnant un candidat naturel pour la partie rationnelle d'une structure de Hodge non-commutative sur l'homologie périodique, ceci étant énoncé sous la forme de la conjecture du réseau. Notre premier résultat de comparaison concerne le cas d'un schéma lisse de type fini sur les complexes -- la conjecture du réseau est alors vraie pour de tels schémas. On montre ensuite que cette conjecture est vraie dans le cas des algèbres associatives de dimension finie. / In this thesis, we give a definition of a topological K-theory of Kontsevich's non-commutative spaces (i.e. of dg-categories) defined over complex numbers. The introduction of this invariant initiates the quest for topological invariants of non-commutative spaces, which are considered as "simplifications" of algebraic ones like algebraic K-theory, cyclic homology, periodic homology as studied by Tsygan, Keller. The main motivation comes from non-commutative Hodge theory in the sense of Katzarkov--Kontsevich--Pantev. In algebraic geometry, the rational part of the Hodge structure is given by rational Betti cohomology, which is the rational cohomology of the underlying space of complex points. The existence of a space associated to a dg-category admits a first answer given by the stack (defined by Toën--Vaquié) classifying perfect dg-modules over this dg-category. The essential ingredient in the definition of the topological K-theory is the topological realization functor of spectral presheaves on the site of complex schemes of finite type. The connective part of the semi-topological K-theory can then be definied as the topological realization of the stack of perfect dg-modules over the space, together with its commutative monoid structure up to homotopy. But to deal with negative K-groups, we realize the presehaf given by non-connective algebraic K-theory. One of our main results relies the two previous definition in the connective case. We show that the topological realization of the presheaf of connective algebraic K-theory for the unit dg-category is equivalent to the usual topological K-theory spectrum. We show this is also true in the non-connective case, using a property of restriction to smooth schemes. This last property leads us to show a generalization of Deligne's proper cohomological descent to the homotopical non-abelian setting. This enables us to define topological K-theory by inverting the Bott element. We point out that the process of the definition involves non-trivial results. We then show that the Chern character from algebraic K-theory to periodic homology factorizes through topological K-theory, giving a natural candidate for the rational part of a non-commutative Hodge structure on the periodic homology of a smooth and proper dg-category. This last claim is written in the form of a conjecture : the lattice conjecture. Our first comparison result deals with the case of a smooth scheme of finite type over complex numbers -- we show the lattice conjecture holds for dg-categories of perfect complexes. We also show this conjecture is true in the case of finite dimensional associative algebras.
74

Ég meina það sé úr Eddu. Jón Rúgmanns avskrift av Uppsala-Eddans Gylfaginning ur handskriften R 683

Romano, Christian January 2013 (has links)
Uppsatsen presenterar en diplomatarisk utgåva av ett stycke text ur handskriften R 683, från senare hälften av 1600-talet. Texten är en avskrift av delen Gylfaginning ur Snorri Sturlusons Edda enligt versionen nedskriven i handskriften DG 11, från tidigt 1300-tal. Uppsatsens syfte är att presentera en hittils relativt ostuderad text som en självständig skriftprodukt, samt försöka att spåra dess specifika drag som skiljer den från dess ursprungstext samt övriga versioner av Snorris Edda. Undersökningen har genomförts utifrån ett nyfilologiskt perspektiv, inte med tanke på dess relation till övriga versioner utan med fokus på vad som egentligen står i handskriften. Resultatet visar att texten i R 683 skiljer sig något från DG 11, och jämförelseundersökningen med övriga Edda-versioner visar att skrivaren, Jón Rúgmann, använt sig av andra källor för sin avskrift, i synnerhet de i handskrifterna Codex Regius, Codex Wormianus samt Peder Resens (Resenius) utgåva av Laufás Edda. Samtidigt visar skrivarens arbete tecken på en personlig kunskap i den medeltida isländska textproduktionen, vilket förklarar de tillägg och kommentarer som inte är direkt tagna ur texter utan tyder på vidare forskning eller förkunskaper. Slutligen lyfter uppsatsen fram Jón Rúgmanns vetenskapliga förtjänster i den nordiska filologins tidiga etablering i Sverige samt presenterar den stora potential i förbisedda handskrifterna som R 683.
75

Dynamics of policy change : three Italian cases

Mele, Valentina January 2014 (has links)
The common research interest of this thesis’s chapters is the dynamics of policy change in the context of the Italian governmental system. The collection of three published papers each included as a chapter in the core of the thesis is preceded by an introduction explaining the theoretical approach and research strategy. The chapters are consistent in following a middle-range processual theory of the politics of public policy decisions in a country case, an event-centric approach to explaining policy choice and an elite-interviewing approach to data collection. The first two chapters, respectively entitled “Government Innovation Policy in Italy (1993-2002): Understanding the Invention and Persistence of a Public Management Reform” and “Dynamics of Electronic Government Policies: The case of Italy (1992-2003)”, examine the dynamics of public management policy change in Italy over the period of a decade, employing the case of the Policy for Government Innovation and the case of the Electronic-Government Policy. The analysis of these two newly reported cases of enduring public management reform is suited to question the argument set by previous literature; that the country’s legalistic administrative culture inevitably suppresses meaningful reform. In particular, the chapters set forth two significant reservations about this argument, namely that the outcomes of public management reform initiatives are more varied than the current literature shows and the theoretical approach in the established literature attributes exagerate causal influence to the governmental system’s legalistic traditions. The third chapter, entitled “Explaining the Unexpected Success of the Smoking Ban in Italy: Political Strategy and Transition to Practice”, analyzes the episode that unfolds in a domain that addresses a general interest reform, very visible to public opinion, unlike public management reform. The chapter follows the issue beyond the pre-decisional stage, uncovering the dynamics of transition to practice: a phase between the formal passage and the full application of a law. A concluding section compares the three chapters, explores the interactions between analytically significant features of the Italian context and the policy cycle, and distils analytical refinements to the notion of policy entrepreneurship.
76

Beyond Bellini : aspects of Italian-Ottoman cultural exchange 1453-1512

Gatward Cevizli, Antonia January 2011 (has links)
Venice has dominated the study of Ottoman-Italian cultural exchange in the Renaissance period, both in publications and, more recently, exhibitions. However, Venice did not have the monopoly in terms of relations with the Ottomans. This thesis looks further afield than Venice and beyond Gentile Bellini’s 1479-81 sojourn in Istanbul, arguably the best-known instance of such intercultural exchange, to reveal the complexity and diversity of Ottoman-Italian contacts and its varied cultural repercussions. This thesis considers the period 1453-1512 covering the reigns of Mehmed II and Bayezid II. It is not a study of cultural exchange through the trade of luxury goods, but instead focuses on the consequences of specific encounters that are mostly diplomatic. These encounters are explored in four case studies: Rimini, Venice, the Papal States and Mantua. Preferring microhistory to large historical generalisations, the scale of investigation in each section is limited to a particular moment of interaction between that region and the Ottoman Empire, and focuses on the individuals involved. Events are considered from both the Italian and Ottoman perspectives in order to reach a more rounded understanding of this complex meeting of cultures. It looks beyond painted and medallic portraits and demonstrates that Ottoman-Italian interaction can be perceived across a range of media. The marks left on Italian visual culture by relations with the Ottomans are revealed to have been as varied as each individual state’s experience. Comparison of each state’s connections with the Ottomans reveals significant differences in their dealings but also highlights certain common aspects such as the role of individuals as channels of exchange, the categories of objects which travelled across Europe and the manner in which cultural and technological exchange were often entwined. By bringing together three other city-states apart from Venice in a single narrative, this thesis provides a more nuanced account of the rich and varied forms of cultural exchange that have long been overshadowed by Bellini’s portrait.
77

The cult of St Nicholas in medieval Italy

Burnett, Sarah January 2009 (has links)
St Nicholas was one of the most popular saints in medieval Italy. His cult attracted the attention of popes, kings and emperors, and his shrine at Bari became an important international pilgrimage destination. This thesis asks how the cult of St Nicholas came to be so widespread and popular in Italy, and why the saint attracted the attention of diverse groups and individuals. This thesis is structured around four chapters. The first demonstrates that through a process of Latinisation the cult of St Nicholas became integrated within Italian literary traditions and within a new spiritual era. Chapter Two reveals that this Latinisation also occurred within the saint’s iconography. Chapters Three and Four are case studies of the cult in Puglia and Venice, locations which claimed possession of the saint’s relics. These case studies show that the general developments that the cult of St Nicholas underwent in Italy, identified in Chapters One and Two, did not apply universally. Instead, the presence of the saint’s relics resulted in a different profile of the saint in Bari and Venice. Through the process of Latinisation, the cult of St Nicholas became updated and remained relevant for its new Italian audience; Chapters Three and Four show alternative ways that the cult of St Nicholas gained widespread popularity. This thesis presents for the first time an iconographical study of St Nicholas in Italian art, which develops existing research of the saint’s Byzantine iconography. Chapter Four presents a profile of the cult of St Nicholas in Venice in the Middle Ages, which is a significant oversight in the literature. The thesis uses a variety of visual and textual sources, in particular fresco and altarpiece representations, archival documents from Venice and Rome (including the Apostolic Visitations), and under-exploited contemporary and antiquarian Venetian sources.
78

Maximising renewable hosting capacity in electricity networks

Sun, Wei January 2015 (has links)
The electricity network is undergoing significant changes in the transition to a low carbon system. The growth of renewable distributed generation (DG) creates a number of technical and economic challenges in the electricity network. While the development of the smart grid promises alternative ways to manage network constraints, their impact on the ability of the network to accommodate DG – the ‘hosting capacity’- is not fully understood. It is of significance for both DNOs and DGs developers to quantify the hosting capacity according to given technical or commercial objectives while subject to a set of predefined limits. The combinational nature of the hosting capacity problem, together with the intermittent nature of renewable generation and the complex actions of smart control systems, means evaluation of hosting capacity requires appropriate optimisation techniques. This thesis extends the knowledge of hosting capacity. Three specific but related areas are examined to fill the gaps identified in existing knowledge. New evaluation methods are developed that allow the study of hosting capacity (1) under different curtailment priority rules, (2) with harmonic distortion limits, and (3) alongside energy storage systems. These works together improve DG planning in two directions: demonstrating the benefit provided by a range of smart grid solutions; and evaluating extensive impacts to ensure compliance with all relevant planning standards and grid codes. As an outcome, the methods developed can help both DNOs and DG developers make sound and practical decisions, facilitating the integration of renewable DG in a more cost-effective way.
79

From metaphor of slavery to metaphor of freedom : Article 18 and the incorporation of migrant prostitutes into Italian society

Testaî, Patrizia January 2008 (has links)
This thesis is concerned with the debate on 'trafficking in persons' as a new form of slavery. It will explore the concept of slavery both historically and in its links with contemporary migration and connected issues of gender, sexuality, and labour exploitation. Within the contemporary debate on 'trafficking', attention has focused in fact predominantly on migrant women and girls involved in sex work and described as 'victims of trafficking for the purpose of sexual exploitation'. This thesis will explore the meaning of slavery in such debate. For this purpose, a research study will be carried out in three Italian cities, focusing on the ways in which such terms as 'slavery', 'trafficking in persons', and 'sexual slavery' are understood and applied within social protection programmes for victims of trafficking which, under Article 18 of the immigration law, grant a special residence permit and opportunities for such victims to work and stay permanently in Italy. The study is based on interviews with key actors working in social protection programmes such as judges, NGO workers, social workers, psychologists, lawyers, and police officers, on interviews with migrant women working in the sex industry and women using protection programmes, and on the analysis of parliamentary speeches and press articles. It will seek to critically assess the validity of 'new slavery' - as 'trafficking' is usually understood - as an expression to understand problems related to contemporary exploitative labour practices within the context of global poverty, dislocation of capital and labour, and restrictive immigration regimes. It will focus on the gender, 'racial', and sexuality aspects of anti-trafficking policies in Italy and how they get linked to citizenship within the socio-legal process enacted by Article 18 of the Italian immigration law. It will finally ask what kind of citizenship is granted to subjects who have been Otherised as 'slaves' on the basis of their gender and sexuality and who, through a postcolonial process of discipline and social control, are incorporated into the Italian society via their 'domestication' within 'proper' sexual, gender, and labour roles (i.e. as domestic workers in Italian families or as wives).
80

Development of Discontinuous Galerkin Method for 1-D Inviscid Burgers Equation

Voonna, Kiran 19 December 2003 (has links)
The main objective of this research work is to apply the discontinuous Galerkin method to a classical partial differential equation to investigate the properties of the numerical solution and compare the numerical solution to the analytical solution by using discontinuous Galerkin method. This scheme is applied to 1-D non-linear conservation equation (Burgers equation) in which the governing differential equation is simplified model of the inviscid Navier-stokes equations. In this work three cases are studied. They are sinusoidal wave profile, initial shock discontinuity and initial linear distribution. A grid and time step refinement is performed. Riemann fluxes at each element interfaces are calculated. This scheme is applied to forward differentiation method (Euler's method) and to second order Runge-kutta method of this work.

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