O objetivo desta dissertação é traçar a situação e a perspectiva da inserção da bicicleta no planejamento de mobilidade em São Paulo e no Brasil. Para tal, estudou-se o processo de formação da cidade e dos elementos de mobilidade urbana na cidade capitalista. Também buscou-se identificar o processo histórico de reprodução da sociedade brasileira, a acumulação entravada. Foram estudados os modelos de implantação de políticas nacionais e os motivos que tornaram alguns países referência em modelo de planejamento cicloviário. Identificou-se o impacto do Protocolo de Quioto na política pró-bicicleta, apresentando elementos do maior impacto mundial, as bicicletas púbicas, ou compartilhamento de bicicletas. Simultaneamente, foi estudada e analisada a produção de uma consultoria, por mim fundada, especializada em planos e projetos cicloviários, com elaboração de projetos em todas as regiões do Brasil. Apresenta-se também a metodologia de planejamento cicloviário que se faz cada vez mais necessária e fomentada pela nova Política Nacional de Mobilidade Urbana, lei que será aplicada a partir de 2015. Por fim, é apresentado um metaprojeto na Avenida Paulista, que demonstra diferentes soluções devido a possibilidades com diversos cenários, e as considerações finais acerca do impacto da política cicloviária na organização e qualificação do espaço. / The objective of this thesis is to outline the situation and the prospect of bicycle integration in mobility planning in São Paulo and Brazil. Therefore, we studied the formation process of the city and the elements of urban mobility in the capitalist city. We also sought to identify the historical process of reproduction of Brazilian society --the impeded accumulation. Models of implementation of national policies and the reasons that made some countries reference in bicycle planning model were studied. We identified the impact of the Kyoto Protocol in the pro bike policies, featuring elements of the its most profound impact: pubic bikes, or bike-sharing. At the same time, was studied and analyzed the work of a consultancy --founded by me-- specialized on cycling plans and projects, with projects done to all regions of Brazil. Then, we introduce the cycling planning methodology, that is increasingly required and encouraged by the new National Policy of Urban Mobility, law that will apply on 2015. Finally, we present a meta project on Paulista Avenue, which demonstrates different solutions due to possibilities according to several scenarios, and the final considerations about the impact of cycling policy on the organization and qualification of space.

Made available in DSpace on 2016-04-28T20:12:53Z (GMT). No. of bitstreams: 1 2007- Marcos Botton Piccin.pdf: 3891788 bytes, checksum: 50ac5d427e99048c73b932fdad6563b0 (MD5) Previous issue date: 2007-08-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work consists of a research that analyzes the underlying sociocultural logics to the productive strategies developed by the landless farmers settled in the rural Settlement called Ceres, RS. That Settlement was formed in the end of 1996 and it received landless farm workers of several areas and municipal districts of Rio Grande do Sul, having different paths and acquired social experiences in the different busy social positions in the structure of relationships of the society. Hence the occupation of the territory and the social-historical development of that state have conformed certain social positions to the poor rural workers as small farmers, temporary and permanent workers, millers, lacemakers, among other generating potentially different principles of action, behaviors, codes and operational modalities that provide a group of knowledge, creeds and a certain practical sense, working as social habitus. In this sense, this sociocultural heterogeneity tends to compose the social processes as much of the camps as of the rural settlements and it can be expressed by the different situations that took the rural workers to the fight for the land, for the different objectives related to the ownership of a lot, as well as for the differentiated projects and future dreams elaborated among those individuals. Then, when in the establishment of awareness, knowledge, projects and future dreams which have been built along the social paths tend to make present and updated face of the found circumstances regarding the differential of powers among the different social agents of the local and regional environment. Like this, the cultivations, handlings and several forms of productive occupation of the land lots for the farmer-seated can also represent that social-cultural heterogeneity forged by the socialhistorical process. In that sense, the research classified the farmer-seated in three productive systems considered as diversified, soy-milk, and soy farmers through a survey questionnaire and it was opted for living the daily of them starting from an interview of a pre-selected sample of seated families. The analysis of the data and information allow considering that the interactions and reactions from those environments do not occur in the same way by the group of the farmer-seated in the establishment of the strategies of social reproduction. The existence of three productive systems in the Settlement tends to correspond to the sociocultural internal factors along the social paths. As a result, the significances attributed to the differentiated forms of productive occupation of the land lots reveal desires and life projects longed for and also differentiated and such objectives are believed to be possible to achieve in the Settlement. . / Este trabalho consiste em uma pesquisa que analisa as l?gicas socioculturais subjacentes ?s estrat?gias produtivas desenvolvidas pelos agricultores-assentados no Assentamento rural Ceres, RS. Esse Assentamento foi formado no final de 1996 e recebeu agricultores sem-terra de v?rias regi?es e munic?pios do Rio Grande do Sul, com diferentes trajet?rias e experi?ncias sociais adquiridas nas diferentes posi??es sociais ocupadas na estrutura de rela??es da sociedade. A ocupa??o do territ?rio e o desenvolvimento s?cio-hist?rico desse estado conformaram determinadas posi??es sociais aos trabalhadores rurais pobres como pequenos agricultores, trabalhadores tempor?rios e permanentes, meeiros, rendeiros, entre outras, gerando, potencialmente, distintos princ?pios de a??o, comportamentos, c?digos e modalidades operacionais que conferem um conjunto de saberes, cren?as e um senso pr?tico determinado, funcionando como habitus sociais. Esta heterogeneidade sociocultural tende a compor os processos sociais tanto dos acampamentos quanto dos assentamentos rurais e pode ser expressada pelas diferentes situa??es que levaram os trabalhadores rurais ? luta pela terra, pelos diferentes objetivos para com a posse de um lote, assim como pelos diferenciados projetos e sonhos de futuro elaborados entre esses indiv?duos. Quando em assentamento os saberes, conhecimentos, projetos e sonhos de futuro constru?dos ao longo das trajet?rias sociais tendem a ser presentificados e atualizados frente ?s circunst?ncias encontradas dos diferenciais de poderes entre os distintos agentes sociais que figuram a ambi?ncia local e regional. Assim, os cultivos, manejos e formas diversas de ocupa??o produtiva dos lotes de terra pelos agricultores-assentados tamb?m podem representar aquela heterogeneidade sociocultural forjada pelo processo s?cio-hist?rico. Nesse sentido, a pesquisa classificou os agricultores-assentados em tr?s sistemas produtivos considerados como diversificado, sojaleite e soja atrav?s de um question?rio tipo survey e optou-se pela viv?ncia do cotidiano dos mesmos a partir do qual se procedeu a entrevista de uma amostra pr?-selecionada de fam?lias assentadas. A an?lise dos dados e informa??es permite considerar que as intera??es e rea??es a essas ambi?ncias n?o se d?o da mesma forma pelo conjunto dos agricultores-assentados no estabelecimento das estrat?gias de reprodu??o social. A exist?ncia de tr?s sistemas produtivos no Assentamento tende a corresponder aos fatores socioculturais internalizados ao longo das trajet?rias sociais. As significa??es atribu?das ?s formas diferenciadas de ocupa??o produtiva dos lotes de terra revelam desejos e projetos de vida almejados tamb?m diferenciados e que se julga poss?vel alcan?ar no Assentamento.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-05T20:40:10Z No. of bitstreams: 1 2016 - Nivia Cl?udia Katica Melo e Silva.pdf: 6493258 bytes, checksum: 88b672c6a18c9f8ac914c14d9d65915d (MD5) / Made available in DSpace on 2017-05-05T20:40:10Z (GMT). No. of bitstreams: 1 2016 - Nivia Cl?udia Katica Melo e Silva.pdf: 6493258 bytes, checksum: 88b672c6a18c9f8ac914c14d9d65915d (MD5) Previous issue date: 2016-06-03 / This research had as goal to analyse the scenes and situations lived by adult population in street situation in your displacement process to Campo Grande, at West Zone, occasioned by the huge international sport events at central region and South Zone of Rio de Janeiro city, between the years 2014 and 2016. The base of the analysis of life on streets is the material collected in research field (observation, participation and interviews with some people in street situation and other ones who work directly with they, mainly inside religious entities that act with people in street situation) and data of population in street situation on Rio de Janeiro city as a whole and more specifically their data in Campo Grande. This work propose to point the vulnerabilities that populations in street situation are subject inside and outside this displacement process through the city, just as well the deficit of public equipments and your agents, limiting the access of these populations to yours most basics rights. / Esta pesquisa teve como objetivo analisar as cenas e situa??es vividas pela popula??o adulta em situa??o de rua no seu processo de deslocamento para Campo Grande, na Zona Oeste, ocasionado pelos grandes eventos internacionais esportivos na regi?o central e na Zona Sul da cidade do Rio de Janeiro, entre os anos de 2014 e 2016. Como base para a an?lise da vida nas ruas est? o material colhido no campo (observa??o, participa??o e entrevistas com algumas pessoas em situa??o de rua e outras que trabalham diretamente com elas, sobretudo em entidades religiosas que tenham a??es com pessoas em situa??o de rua) e dados da popula??o em situa??o de rua na cidade do Rio de Janeiro como um todo e mais especificamente dados em Campo Grande. Este trabalho se prop?e a apontar as vulnerabilidades que as popula??es em situa??o de rua est?o sujeitas dentro e fora deste processo de mobilidade pela cidade, bem como o d?ficit de equipamentos p?blicos e seus agentes, restringindo o acesso dessas popula??es aos seus direitos mais b?sicos.

La croissance démographique dans les zones urbaines représente un problème pour la planification des transports. La surcharge des systèmes de transport urbains entraîne des coûts monétaires importants et des problèmes environnementaux. Des mesures politiques sont alors nécessaires pour réduire le niveau de congestion et accroître l'efficacité des systèmes de transport. À court terme, les simulateurs de trafic pourraient constituer un outil puissant pour la conception de solutions innovantes. Mais les simulateurs de trafic classiques sont exigeants sur le plan informatique pour les applications à grande échelle. De plus, la mise en place du scénario de simulation est complexe. Une modélisation de trafic agrégée pourrait être une bonne solution (Daganzo-2007, Geroliminis-2008). Le réseau routier des villes est divisé en régions, où un diagramme fondamental macroscopique bien défini (MFD) régule les conditions de circulation à l'intérieur de chacune. Le MFD concerne le débit et la densité de trafic moyens dans une région. Malgré que l’idée d’agréger le réseau de la ville soit simple, il soulève plusieurs défis qui n’ont pas encore été abordés. Jusqu'à aujourd'hui, seule (Yildirimoglu-2014) propose un cadre d'affectation dynamique du trafic pour les réseaux régionaux et les modèles MFD. Ce cadre est basé sur le modèle Logit multinomial et ne traite pas explicitement des distributions de longueurs de parcours. De plus, leur structure ne considère pas que les utilisateurs sont différents les uns des autres et ont des objectifs et des préférences différents pour leurs voyages. L'objectif de cette thèse est double. Tout d'abord, l'influence du comportement des utilisateurs sur la performance globale du réseau routier d’une ville est étudiée. Cette analyse se concentre sur la vitesse moyenne du réseau et ses capacités internes et de sortie, en comparant différents modèles tenant compte des différents types de comportement des utilisateurs par rapport à l'équilibre utilisateur déterministe et stochastique. En second lieu, un cadre innovant et complet d’affectation dynamique du trafic pour les modèles multirégionaux basés sur le MFD est proposé. Ce cadre est divisé en plusieurs étapes et repose sur les connexions entre la ville et les réseaux régionaux. Dans un premier temps, des méthodes systématiques de mise à l’échelle sont proposées pour rassembler les voies régionales. Dans un deuxième temps, quatre méthodes sont discutées pour calculer les distributions de longueurs de parcours pour caractériser ces chemins régionaux. Dans la troisième étape, un modèle de chargement de réseau qui considère les distributions de longueurs de parcours explicitement calculées et l’évolution des vitesses moyennes régionales est proposé. Enfin, ce cadre d'affectation dynamique du trafic est étendu pour prendre en compte les usager qui ont une aversion au regret ou une rationalité imparfaite. Cette thèse s'inscrit dans le cadre d'un projet européen ERC intitulé MAGnUM: approche de modélisation du trafic multi-échelle et multimodal pour la gestion durable de la mobilité urbaine. / The population growth in urban areas represents an issue for transportation planning. This overload of urban transportation systems, leading to significant monetary costs and environmental issues. Policy measures are then needed to decrease the level of congestion and increase the efficiency of transportation systems. In a short term, traffic simulators might be a powerful tool that helps to design innovative solution. But, the classical traffic simulators are computationally demanding for large scale applications. Moreover, the set up of the simulation scenario is complex. An aggregated traffic modeling might be a good solution (Daganzo, 2007; Geroliminis and Daganzo, 2008). The city network is divided into regions where a well-defined Macroscopic Fundamental Diagram (MFD) regulates the traffic conditions inside each one. The MFD relates the average traffic flow and density inside a region. Despite the idea of aggregating the city network is simple, it brings several challenges that have not yet been addressed. Up to today, only Yildirimoglu and Geroliminis (2014) proposed a dynamic traffic assignment framework for regional networks and MFD models. This framework is based on the simple Multinomial Logit model and does not explicitly deal with trip length distributions. Moreover, their framework does not consider that users are different from each other and have different purposes and preferences for their travels. The goal of this PhD dissertation is to twofold. First, the influence of the users behavior on the global network performance is investigated. This analysis focus on the network mean speed and its internal and outflow capacities, comparing different models that account for different kinds of users behavior against the Deterministic and Stochastic User Equilibrium. Second, an innovative and complete dynamic traffic assignment framework for multi-regional MFD-based models is proposed. This framework is divided into several milestones and is based on the connections between the city and regional networks. In a first step, systematic scaling-up methods are proposed to gather the regional paths. In a second step, four methods are discussed to calculate the distributions of trip lengths that characterize these regional paths. In the third step, a network loading model that considers distributions of trip lengths that are explicitly calculated and the evolution of the regional mean speeds is proposed. Finally, this dynamic traffic assignment framework is extended to account for bounded rational and regret-averse users. This PhD is part of a European ERC project entitled MAGnUM: Multiscale and Multimodal Traffic Modeling Approach for Sustainable Management of Urban Mobility.

La sécurisation inhérente aux échanges dans les environnements dynamiques et distribués, dépourvus d’une coordination centrale et dont la topologie change perpétuellement, est un défi majeur. Dans le cadre de cette thèse, on se propose en effet de définir une infrastructure de sécurité adaptée aux contraintes des systèmes P2P actuels. Le premier volet de nos travaux consiste à proposer un intergiciel, appelé SEMOS, qui gère des sessions sécurisées et mobiles. SEMOS permet en effet de maintenir les sessions sécurisées actives et ce, même lorsque la configuration réseau change ou un dysfonctionnement se produit. Cette faculté d’itinérance est rendue possible par la définition d’un nouveau mécanisme de découplage afin de cloisonner l’espace d’adressage de l’espace de nommage ; le nouvel espace de nommage repose alors sur les tables de hachage distribuées (DHT). Le deuxième volet définit un mécanisme distribué et générique d’échange de clés adapté à l’architecture P2P. Basé sur les chemins disjoints et l’échange de bout en bout, le procédé de gestion des clés proposé est constitué d’une combinaison du protocole Diffie-Hellman et du schéma à seuil(k, n) de Shamir. D’une part, l’utilisation des chemins disjoints dans le routage des sous-clés compense l’absence de l’authentification certifiée, par une tierce partie, consubstantielle au protocole Diffie-Hellman et réduit, dans la foulée, sa vulnérabilité aux attaques par interception. D’autre part, l’extension de l’algorithme Diffie-Hellman par ajout du schéma à seuil (k, n) renforce substantiellement sa robustesse notamment dans la segmentation des clés et/ou en cas de défaillances accidentelles ou délibérées dans le routage des sous-clés. Enfin, les sessions sécurisées mobiles sont évaluées dans un réseau virtuel et mobile et la gestion des clés est simulée dans un environnement générant des topologies P2P aléatoires. / Securing communications in distributed dynamic environments, that lack a central coordination point and whose topology changes constantly, is a major challenge.We tackle this challenge of today’s P2P systems. In this thesis, we propose to define a security infrastructure that is suitable to the constraints and issues of P2P systems. The first part of this document presents the design of SEMOS, our middleware solution for managing and securing mobile sessions. SEMOS ensures that communication sessions are secure and remain active despite the possible disconnections that can occur when network configurations change or a malfunction arises. This roaming capability is implemented via the definition of a new addressing space in order to split up addresses for network entities with their names ; the new naming space is then based on distributed hash tables(DHT). The second part of the document presents a generic and distributed mechanism for a key exchange method befitting to P2P architectures. Building on disjoint paths andend-to-end exchange, the proposed key management protocol consists of a combination of the Diffie-Hellman algorithm and the Shamir’s (k, n) threshold scheme. On the onehand, the use of disjoint paths to route subkeys offsets the absence of the third party’s certified consubstantial to Diffie-Hellman and reduces, at the same time, its vulnerability to interception attacks. On the other hand, the extension of the Diffie-Hellman algorithm by adding the threshold (k, n) scheme substantially increases its robustness, in particular in key splitting and / or in the case of accidental or intentional subkeys routing failures. Finally, we rely on a virtual mobile network to assess the setup of secure mobile sessions.The key management mechanism is then evaluated in an environment with randomly generated P2P topologies.

No presente trabalho, é abordada a operação de transporte de cargas fracionadas, especificamente a determinação de quais linhas de transporte deverão ser ofertadas dentro de uma rede de terminais, de maneira a atender toda a demanda no nível de serviço desejado ao menor custo possível. Para tanto, é feita inicialmente uma descrição do problema de transporte de carga fracionada, seguido de uma revisão bibliográfica de trabalhos anteriores que já tenham abordado o tema. É então realizada a delimitação do escopo do estudo e a proposição de um modelo matemático em programação linear inteira-mista. Em seguida, é apresentado um algoritmo de resolução, consistindo na aplicação de uma heurística construtiva e uma heurística de melhoria, ambas embasadas na aplicação de caminhos mínimos com janelas de tempo a partir de custos marginais. O método é delineado para três versões do problema, estipuladas a partir de diferentes tratamentos à restrição de caminhos em formato de árvore dentro do sistema. Primeiramente, o algoritmo é aplicado a pequenas instâncias fictícias, realizando a comparação com a modelagem em programação linear inteira-mista proposta. Na maioria dos casos, não houve diferença nos valores de função objetivo encontrados, embora tenham sido identificados gaps grandes no processamento. Posteriormente, é realizada a aplicação a dados reais de uma transportadora brasileira. Para as três versões do problema, a redução de custos potencial identificada é significativa, com tempos de processamento similares ou menores do que o encontrado na literatura. Por fim, os resultados obtidos são discutidos sendo apresentadas considerações finais acerca do trabalho realizado e possíveis melhorias para pesquisas futuras. / At the present work, the operation of less-than-truckload (LTL) will be studied, more specifically the determination of which lines will be offered in a network of terminals. The service network design must attend all demands, respecting their deadlines while aiming cost reductions. The objective of this work is to propose algorithms to solve the service network design problem of LTL operations, reducing operation costs while respecting specified service levels. First, a brief introduction to the problem is made, and similar research is reviewed. Then the scope of the research is determined and a mathematical model of the problem in mixed-integer programming is presented. Next, an algorithm is proposed, consisting in a constructive heuristic followed by a local search. Both phases are based on finding minimum paths with time windows using marginal costs along the network. Three different versions of the problem are analyzed, shifting the approach given to the constraint of in-tree structure that shipments should follow in the network. The algorithm is firstly tested to small fictional instances, allowing comparison to the mixed programming model proposed earlier. No relevant differences between objective functions were found, even though substantial gaps values were identified during processing. A second test used a real dataset of a Brazilian LTL carrier. In all versions of the problem the operation cost reduction was promising, with processing times similar to the ones found in literature. The conclusion provides a discussion of the obtained results and recommendations for future research.

The objective of this study was to develop and validate practical modeling methods for investigating load paths and system behavior in a realistic, light-frame wood structure. The modeling methods were validated against full-scale tests on subassemblies and an L-shaped house. The model of the L-shaped house was then modified and used to investigate the effects of re-entrant corners, wall openings and gable-end retrofits on system behavior and load paths. Results from this study showed that the effects of adding re-entrant corners and wall openings on uplift load distributions were dependent on the orientation of the trusses with respect to the walls. Openings added to walls parallel to the trusses had the least effect on loads carried by the remaining walls in the building. Varying re-entrant corner dimensions of the L-shaped house under ASCE 7-05 (ASCE 2005) design wind loads caused increasing degrees of torsion throughout the house, depending on the relative location and stiffness of the in-plane walls (parallel to the applied wind loads) as well as the assumed direction of the wind loads. Balancing the stiffness of the walls on either side of the house with the largest re-entrant corner helped to decrease torsion in the structure somewhat. Finally, although previous full-scale tests on gable-end sections verified the effectiveness of the gable-end retrofit that was recently adopted into the 2010 Florida building code, questions remained about the effects of the retrofit on torsion in a full building. The current study found that adding the gable-end retrofits to the L-shaped house did not cause additional torsion. / Graduation date: 2013

With the advances in video compression and networking techniques, the last ten years have witnessed an explosive growth of video applications over the Internet. However, the service model of the current best-effort network was never engineered to handle video traffic and, as a result, video applications still suffer from varying and unpredictable network conditions, in terms of bandwidth, packet loss and delay. To address these problems, a lot of innovative techniques have been proposed and researched. Among them, scalable video coding is a promising one to cope with the dynamics of the available bandwidth and heterogeneous terminals. This work aims at improving the efficacy of scalable video transport over IP networks. In this work, we first propose an optimal interleaving scheme combined with motion-compensated fine granularity scalability video source coding and unequal loss protection schemes, under an imposed delay constraint. The network is modeled as a packet-loss channel with random delays. The motion compensation prediction, ULP allocation and the depth of the interleaver are jointly optimized based on the network status and the delay constraint. We then proceed to investigate the multiple path transport technique. A unified approach which incorporates adaptive motion compensation prediction, multiple description coding and unequal multiple path allocation, is proposed to improve both the robustness and error resilience property of the video coding and transmission system, while the delivered video quality is improved simultaneously. To analytically investigate the efficacy of error resilient transport schemes for progressively encoded sources, including unequal loss protection, best-effort and FEC transport schemes, we develop evaluation and optimization approaches for these transport schemes. In this part of the work, the network is modeled as an M/D/1/K queue, and then a comprehensive queueing analysis is provided. Armed with these results, the efficacy of these transport schemes for progressively encoded sources are investigated and compared.

El tema d'aquesta tesi és l'enumeració de permutacions amb subseqüències prohibides respecte a certs estadístics, i l'enumeració de permutacions que eviten subseqüències generalitzades.Després d'introduir algunes definicions sobre subseqüències i estadístics en permutacions i camins de Dyck, comencem estudiant la distribució dels estadístics -nombre de punts fixos' i -nombre d'excedències' en permutacions que eviten una subseqüència de longitud 3. Un dels resultats principals és que la distribució conjunta d'aquest parell de paràmetres és la mateixa en permutacions que eviten 321 que en permutacions que eviten 132. Això generalitza un teorema recent de Robertson, Saracino i Zeilberger. Demostrem aquest resultat donant una bijecció que preserva els dos estadístics en qüestió i un altre paràmetre. La idea clau consisteix en introduir una nova classe d'estadístics en camins de Dyck, basada en el que anomenem túnel.A continuació considerem el mateix parell d'estadístics en permutacions que eviten simultàniament dues o més subseqüències de longitud 3. Resolem tots els casos donant les funcions generadores corresponents. Alguns casos són generalitzats a subseqüències de longitud arbitrària. També descrivim la distribució d'aquests paràmetres en involucions que eviten qualsevol subconjunt de subseqüències de longitud 3. La tècnica principal consisteix en fer servir bijeccions entre permutacions amb subseqüències prohibides i certs tipus de camins de Dyck, de manera que els estadístics en permutacions que considerem corresponen a estadístics en camins de Dyck que són més fàcils d'enumerar.Tot seguit presentem una nova família de bijeccions del conjunt de camins de Dyck a sí mateix, que envien estadístics que apareixen en l'estudi de permutacions amb subseqüències prohibides a estadístics clàssics en camins de Dyck, la distribució dels quals s'obté fàcilment. En particular, això ens dóna una prova bijectiva senzilla de l'equidistribució de punts fixos en les permutacions que eviten 321 i en les que eviten 132. A continuació donem noves interpretacions dels nombres de Catalan i dels nombres de Fine. Considerem una classe de permutacions definida en termes d'aparellaments de 2n punts en una circumferència sense creuaments. N'estudiem l'estructura i algunes propietats, i donem la distribució de diversos estadístics en aquests permutacions.En la següent part de la tesi introduïm una noció diferent de subseqüències prohibides, amb el requeriment que els elements que formen la subseqüència han d'aparèixer en posicions consecutives a la permutació. Més en general, estudiem la distribució del nombre d'ocurrències de subparaules (subseqüències consecutives) en permutacions. Resolem el problema en diversos casos segons la forma de la subparaula, obtenint-ne les funcions generadores exponencials bivariades corresponents com a solucions de certes equacions diferencials lineals. El mètode està basat en la representació de permutacions com a arbres binaris creixents i en mètodes simbòlics.La part final tracta de subseqüències generalitzades, que extenen tant la noció de subseqüències clàssiques com la de subparaules. Per algunes subseqüències obtenim nous resultats enumeratius. Finalment estudiem el comportament assimptòtic del nombre de permutacions de mida n que eviten una subseqüència generalitzada fixa quan n tendeix a infinit. També donem fites inferiors i superiors en el nombre de permutacions que eviten certes subseqüències.

The limiting behavior of weighted paths associated with the semidefinite program (SDP) map $X^{1/2}SX^{1/2}$ was studied and some applications to error bound analysis and superlinear convergence of a class of primal-dual interior-point methods were provided. A new approach for solving large-scale well-structured sparse SDPs via a saddle point mirror-prox algorithm with ${cal O}(epsilon^{-1})$ efficiency was developed based on exploiting sparsity structure and reformulating SDPs into smooth convex-concave saddle point problems. An iterative solver-based long-step primal-dual infeasible path-following algorithm for convex quadratic programming (CQP) was developed. The search directions of this algorithm were computed by means of a preconditioned iterative linear solver. A uniform bound, depending only on the CQP data, on the number of iterations performed by a preconditioned iterative linear solver was established. A polynomial bound on the number of iterations of this algorithm was also obtained. One efficient ``nearly exact' type of method for solving large-scale ``low-rank' trust region subproblems was proposed by completely avoiding the computations of Cholesky or partial Cholesky factorizations. A computational study of this method was also provided by applying it to solve some large-scale nonlinear programming problems.