Dissertationen zum Thema „Transport connection“

Given any form of mobility management through wireless communication, one useful enhancement is improving the reliability and robustness of transport-layer connections in a heterogeneous mobile environment. This is particularly true in the case of mobile networks with multiple vertical handovers. In this thesis, issues and challenges in mobility management for mobile terminals in such a scenario are addressed, and a number of techniques to facilitate and improve efficiency and the QoS for such a handover are proposed and investigated. These are initially considered in an end-to-end context and all protocols and changes happened in the middleware of the connection where the network is involved with handover issues and end user transparency is satisfied. This thesis begins by investigating mobility management solutions particularly the transport layer models, also making significant observation pertinent to multi-homing for moving networks in general. A new scheme for transport layer tunnelling based on SCTP is proposed. Consequently a novel protocol to handle seamless network mobility in heterogeneous mobile networks, named nSCTP, is proposed. Efficiency of this protocol in relation to QoS for handover parameters in an end-to-end connection while wired and wireless networks are available is considered. Analytically and experimentally it has been proved that this new scheme can significantly increase the throughput, particularly when the mobile networks roam frequently. The detailed plan for the future improvements and expansion is also provided.

While developing networking for games and applications, developers have a list of network specific requirements to be met as well as decide how to meet them. It is not always easy to decide what protocol is best suited for a given network configuration, or what is the best size of a data packet. By performing a comparative analysis, it becomes possible to identify how protocols, packet size, and network configuration impact the one-way travel time and throughput of a given implementation. The result shows how the different implementations compared against each other and the analysis tries to determine why they perform as they do. This gives a good overview of the pros and cons of how TCP, TCP(N), UDP, and RakNet, behave and perform over LANs and WLANs with varying packet size.

La ràpida evolució d’Internet i l’àmplia gamma de noves aplicacions (per exemple, multimèdia, videoconferència, jocs en línia, etc.) ha fomentat canvis revolucionaris en la manera com ens comuniquem. A més, algunes d’aquestes aplicacions demanden grans quantitats de recursos d’ample de banda amb diversos requeriments de qualitat de servei (QoS). El desenvolupament de la multiplexació per divisió de longitud d’ona (WDM) en els anys noranta va fer molt rendible la disponibilitat d’ample de banda. Avui dia, les tecnologies de commutació òptica de circuits són predominants en el nucli de la xarxa, les quals permeten la configuració de canals (lightpaths) a través de la xarxa. No obstant això, la granularitat d’aquests canals ocupa tota la longitud d’ona, el que fa que siguin ineficients per a proveir canals de menor ample de banda (sub-longitud d’ona). Segons la comunitat científica, és necessari augmentar la transparència dels protocols, així com millorar l’aprovisionament d’ample de banda de forma dinàmica. Per tal de fer això realitat, és necessari desenvolupar noves arquitectures. La commutació òptica de ràfegues i de paquets (OBS/OPS), són dues de les tecnologies proposades. Aquesta tesi contribueix amb tres arquitectures de xarxa destinades a millorar el transport de dades sub-longitud d’ona. En primer lloc, aprofundim en la naturalesa sense connexió en OBS. En aquest cas, la xarxa incrementa el seu dinamisme a causa de les transmissions a ràfega. A més, les col·lisions entre ràfegues degraden el rendiment de la xarxa fins i tot a càrregues molt baixes. Per fer front a aquestes col·lisions, es proposa un esquema de resolució de col·lisions pro actiu basat en un algorisme d’encaminament i assignació de longitud d’ona (RWA) que balanceja de forma automàtica i distribuïda la càrrega en la xarxa. En aquest protocol, el RWA i la transmissió de ràfegues es basen en l’explotació i exploració de regles de commutació que incorporen informació sobre contencions i encaminament. Per donar suport a aquesta arquitectura, s’utilitzen dos tipus de paquets de control per a l’encaminament de les ràfegues i l’actualització de les regles de commutació, respectivament. Per analitzar els beneficis del nou algorisme, s’utilitzen quatre topologies de xarxa diferents. Els resultats indiquen que el mètode proposat millora en diferents marges la resta d’algorismes RWA en funció de la topologia i sense penalitzar altres paràmetres com el retard extrem a extrem. La segona contribució proposa una arquitectura híbrida sense i orientada a connexió sobre la base d’un protocol de control d’accés al medi (MAC) per a xarxes OBS (DAOBS). El MAC ofereix dos mètodes d’accés: arbitratge de cua (QA) per a la transmissió de ràfegues sense connexió, i pre-arbitratge (PA) per serveis TDM orientats a connexió. Aquesta arquitectura permet una àmplia gamma d’aplicacions sensibles al retard i al bloqueig. Els resultats avaluats a través de simulacions mostren que en l’accés QA, les ràfegues de més alta prioritat tenen garantides zero pèrdues i latències d’accés molt baixes. Pel que fa a l’accés PA, es reporta que la duplicació de la càrrega TDM augmenta en més d’un ordre la probabilitat de bloqueig, però sense afectar en la mateixa mesura les ràfegues sense connexió. En aquest capítol també es tracten dos dels problemes relacionats amb l’arquitectura DAOBS i el seu funcionament. En primer lloc, es proposa un model matemàtic per aproximar el retard d’accés inferior i superior com a conseqüència de l’accés QA. En segon lloc, es formula matemàticament la generació i optimització de les topologies virtuals que suporten el protocol per a l’escenari amb tràfic estàtic. Finalment, l’última contribució explora els beneficis d’una arquitectura de xarxa òptica per temps compartit (TSON) basada en elements de càlcul de camins (PCE) centralitzats per tal d’evitar col·lisions en la xarxa. Aquesta arquitectura permet garantir l’aprovisionament orientat a connexió de canals sub-longitud d’ona. En aquest capítol proposem i simulem tres arquitectures GMPLS/PCE/TSON. A causa del enfocament centralitzat, el rendiment de la xarxa depèn en gran mesura de l’assignació i aprovisionament de les connexions. Amb aquesta finalitat, es proposen diferents algorismes d’assignació de ranures temporals i es comparen amb les corresponents formulacions de programació lineal (ILP) per al cas estàtic. Per al cas de tràfic dinàmic, proposem i avaluem mitjançant simulació diferents heurístiques. Els resultats mostren els beneficis de proporcionar flexibilitat en els dominis temporal i freqüencial a l’hora d’assignar les ranures temporals.
The rapid evolving Internet and the broad range of new data applications (e.g., multimedia, video-conference, online gaming, etc.) is fostering revolutionary changes in the way we communicate. In addition, some of these applications demand for unprecedented amounts of bandwidth resources with diverse quality of service (QoS). The development of wavelength division multiplexing (WDM) in the 90's made very cost-effective the availability of bandwidth. Nowadays, optical circuit switching technologies are predominant in the core enabling the set up of lightpaths across the network. However, full-wavelength lightpath granularity is too coarse, which results to be inefficient for provisioning sub-wavelength channels. As remarked by the research community, an open issue in optical networking is increasing the protocol transparency as well as provisioning true dynamic bandwidth allocation at the network level. To this end, new architectures are required. Optical burst/packet switching (OBS/OPS) are two such proposed technologies under investigation. This thesis contributes with three network architectures which aim at improving the sub-wavelength data transport from different perspectives. First, we gain insight into the connectionless nature of OBS. Here, the network dynamics are increased due to the short-lived burst transmissions. Moreover, burst contentions degrade the performance even at very low loads. To cope with them, we propose a proactive resolution scheme by means of a distributed auto load-balancing routing and wavelength assignment (RWA) algorithm for wavelength-continuity constraint networks. In this protocol, the RWA and burst forwarding is based on the exploitation and exploration of switching rule concentration values that incorporate contention and forwarding desirability information. To support such architecture, forward and backward control packets are used in the burst forwarding and updating rules, respectively. In order to analyze the benefits of the new algorithm, four different network topologies are used. Results indicate that the proposed method outperforms the rest of tested RWA algorithms at various margins depending on the topology without penalizing other parameters such as end-to-end delay. The second contribution proposes a hybrid connectionless and connection-oriented architecture based on a medium access control (MAC) protocol for OBS networks (DAOBS). The MAC provides two main access mechanisms: queue arbitrated (QA) for connectionless bursts and pre-arbitrated (PA) for TDM connection-oriented services. Such an architecture allows for a broad range of delay-sensitive applications or guaranteed services. Results evaluated through simulations show that in the QA access mode highest priority bursts are guaranteed zero losses and very low access latencies. Regarding the PA mode, we report that doubling the offered TDM traffic load increases in more than one order their connection blocking, slightly affecting the blocking of other connectionless bursts. In this chapter, we also tackle two of the issues related with the DAOBS architecture and its operation. Firstly, we model mathematically the lower and upper approximations of the access delay as a consequence of the connectionless queue arbitrated access. Secondly, we formulate the generation of the virtual light-tree overlay topology for the static traffic case.

Thesis: S.B., Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences, 2006.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 22).
The transport of sediment is often separated into two components, bedload and suspended load. This division is important because bedload has a dominant control on channel morphology while suspended load dominates the formation of overbank deposits. Experimental data has related the style of sediment transport to mean flow conditions and bed topography. However direct application of this method in natural, sandy rivers is difficult due to large variabilities in flow. We propose a method for determining local flow conditions using the distribution of grain sizes traveling in the water column. Local shear velocity is found by fitting the Rouse equation for suspended sediment transport to measured sediment concentrations. Empirical criteria for distinguishing between suspended load and bedload are used to determine the fraction of sediment traveling in each respective mode. Application of this method to the Niobrara River, Nebraska, shows that -80 % of the sediment is traveling as suspended load, ~ 20 % is traveling in a transitional mode between bedload and suspended load and less than 1 % is traveling as pure bedload. We establish an unambiguous connection between grain size and the style of sediment transport and highlight the importance of the transitional transport mode in natural systems.
by Vivian Leung.
S.B.

FR :Malgré des pratiques de mobilité qui se diversifient, le poids de la voiture au sein des déplacements intrabruxellois reste important. Les nuisances engendrées par ces pratiques sont aussi bien d’ordre économique, social, qu’environnemental et forment un système complexe dont les conséquences dommageables pour la collectivité sont de surcroît accentuées par le contexte urbain.En s’inscrivant dans une logique visant dès lors à renforcer l’utilisation des transports publics et à mieux connecter les différentes parties de la ville, cette recherche pose la question de la desserte des quartiers bruxellois et particulièrement celle d’une meilleure compréhension des logiques sous-jacentes. Pour y répondre, la thèse combine une approche théorique basée sur l’analyse de la littérature scientifique ainsi qu’une approche empirique dont la Région de Bruxelles-Capitale constitue le cas d’étude.Ce faisant, les mesures réalisées à l’heure de pointe matinale d’un jour ouvrable mettent en évidence une forte hétérogénéité des temps de parcours, y compris s’agissant de rejoindre une série de pôles d’activités de premier plan. Il apparaît également que la variance observée est subordonnée à des logiques radiales et concentriques, et que sa partie expliquée n’est pas liée uniquement aux facteurs les plus fréquemment mis en évidence au sein de la littérature, tels que ceux se rapportant à la densité.Par ailleurs, le trafic automobile pèse encore lourdement sur les temps de parcours, les allongeant en moyenne d’un quart en dépit des politiques menées ces dernières années, visant à protéger les transports publics. Mais à côté de cela, l’organisation interne des réseaux a également un impact considérable, ce qui souligne le rôle des opérateurs de transport. La contribution importante, actuelle ou potentielle, des opérateurs autres que la STIB est d’ailleurs révélée.Enfin, devant le manque de cohérence des pouvoirs publics, les résultats obtenus montrent également tout l’intérêt de faire de l’accessibilité des quartiers en transport public un objectif fort de la politique régionale. En effet, alors que 30% de la population bruxelloise réside actuellement au sein de quartiers présentant un déficit d’accessibilité compte tenu de sa localisation, se pose la question d’une vision permettant de lier, sur le long terme, le développement de la ville à des pratiques de mobilités plus durables, ce que permet précisément ce concept géographique fondamental.
EN :Despite mobility practices which are becoming more diversified, the proportion of cars used for travel within Brussels remains significant. The harm caused by these practices has an economic, social and environmental impact, and forms a complex system with detrimental effects on the community, which are more pronounced in the urban context.In a perspective aimed at reinforcing the use of public transport and at making better connections between the different parts of the city, the present research raises questions regarding the service provided in the neighbourhoods of Brussels and, in particular, the underlying rationales and how to have a better understanding of them. In order to answer these questions, the thesis combines a theoretical approach based on an analysis of the academic literature and an empirical approach for which the Brussels-Capital Region constitutes the case study.In doing so, the measurements taken during the morning rush hour on a weekday highlight a marked heterogeneity in travel time, including travel to a series of major poles of activity. It also appears that the variance observed is subordinate to radial and concentric logic, and that the part of it which is accounted for is not only linked to the factors which are highlighted most often in the literature, such as those related to density.Furthermore, car traffic still weighs heavily on travel time, increasing its length by one quarter on average, despite the policies implemented in recent years, aimed at protecting public transport. But in addition to this, the internal organisation of networks also has a considerable impact, which underlines the role of transport operators. The significant contribution – present or potential – of operators other than STIB is also revealed.Finally, faced with the lack of coherence of the public authorities, the results obtained also show how important it is to make the accessibility of neighbourhoods by public transport a main objective of regional policy. While 30% of the population of Brussels currently resides in neighbourhoods with poor accessibility due to their location, the question is raised with regard to a vision allowing a connection between the development of the city and more sustainable mobility practices in the long term, which is precisely what this fundamental geographical concept allows.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

This thesis asks: how are megaprojects legitimated, with civil society seen as a source of the legitimacy that state and market institutions often lack. Civil society is conceived as a political realm in which decisions are challenged and in which there is also public deliberation of the issues decisions generate. With civil society organisations (CSOs) increasingly seen by policy-makers as a means of delivering public goods the role of civil society is changing. In order to reflect this change a broader concept of civil society is developed within this thesis. This, in turn, contributes to the megaproject literature as the participation of civil society is increasingly seen as a prerequisite for more open forms of decision-making. The planning and appraisal of High Speed Two, a proposed UK high speed rail connection, provides a case study in which the roles played by CSOs are interpreted using ethnography, based upon observations conducted within the 'public' formed of CSOs responding to the proposals, and discourse analysis of key policy documents. The history of the project and the governing principles of speed, of operation and implementation, are identified in the framing of the policy discourse as are the ways in which organisations challenging these principles develop alternative proposals. The findings are that the approach to planning and appraisal has, in this case, remained largely closed to civil society. The practices of the delivery bodies, governed by market principles and exhibiting undue haste to implement the project, have generated considerable mistrust and, for many, delegitimised the process and the institutions delivering it. This failure of public bodies suggests a failure to appreciate the importance of CSOs in establishing appropriate institutional frameworks for megaproject governance. These are required if decisions of this type are to be seen to reflect broad public rather than narrow private interests.

In der vorliegenden Arbeit wurden Verfahren entwickelt und getestet, um Prioritätsstufen für öffentliche Verkehrsmittel zur fahrtkonkreten Beeinflussung von Lichtsignalanlagen zu ermitteln und darüber hinaus Anschlüsse im öffentlichen Personennahverkehr zu sichern. Die Testergebnisse zeigen, dass die Ziele, eine höhere Pünktlichkeit und eine höhere Anschlusssicherheit, sehr gut erreicht werden.

La mondialisation se manifeste comme une évidence ordinaire, à tous les coins de la planète. Comme beaucoup de nos contemporains, nous sommes persuadés de vivre un phénomène complètement inédit. Pour l’historien économiste, parler de mondialisation au singulier reviendrait à ignorer toutes les autres. Il n’est donc pas question ici de nier la vigueur de l’actuelle mondialisation, mais de bien saisir l’ampleur d’un phénomène permanent désormais lié à la conteneurisation. C’est d’ailleurs à la lumière du passé qu’on peut le mieux comprendre les débats actuels et appréhender l’avenir. Mais l’avenir est en grande partie déterminé par un certain nombre de facteurs de changement. S’il n’est pas possible de prédire l’aboutissement final du jeu de ces facteurs, on peut néanmoins spéculer sur la façon dont chacun d’eux peut influer sur l’avenir de l’économie européenne en général, et sur les conséquences qui peuvent en résulter pour la desserte de l’Europe en trafic conteneurisé. Certains de ces facteurs peuvent directement influer sur les points forts et les points faibles des modèles existants ; d’autres peuvent avoir des impacts indirects.Ce travail de thèse se veut un essai dédié à tous les praticiens et universitaires intéressés par le commerce maritime. Ce n’est pas un écrit de certitudes ou bien encore un concentré d’érudition; il ne cherche pas à traiter de tous les aspects du transport maritime et de l’histoire économique de l’Europe. L’Europe, qui ne représente que 7% des terres émergées, est une péninsule bordée de trois cotés par la mer et qui ne dispose sur le quatrième coté d’aucune limite géographique particulièrement nette la séparant du reste du continent eurasiatique. Cette Europe géographique a d’ailleurs rarement coïncidé avec l’Europe économique. Il faut, en effet, considérer que la vaste région d’Europe de l’est et du Sud-est fut envahie et asservie par des conquérants non européens, dont elle ne fut libérée qu’au bout de plusieurs siècles. En fait, l’Europe a toujours été à géométrie variable, ce qui est normal, car elle est une résultante depuis les temps antiques de toutes les invasions et de tous les échanges eurasiatiques. Après la découverte des Amériques, les Européens ont développé le commerce à l’échelle de la planète et imposé leur hégémonie jusqu’en 1914. Aux épices et autres objets orientaux, se sont ajoutés les produits des « Indes occidentales». Cette position centrale, acquise grâce à une supériorité démographique et technique procède d’un double impérialisme économique et centralisateur d’abord contesté au début du 20ème siècle et aujourd’hui largement condamné. Avec d’énormes capacités de transport et de très bas coûts, la conteneurisation accompagne depuis plus de cinquante ans la mondialisation et a totalement révolutionnée le transport de lignes régulières des marchandises diverses. Dès lors, une question permanente touchant à la globalisation des échanges et à la navigation vient se poser sous différentes formes dans cette thèse à savoir l’accès au marché mondial de L’Europe lié assurément à la performance des infrastructures de l’Europe mais plus encore à la circulation planétaire. L’avenir de l’Europe passe inéluctablement par la Méditerranée et il est contrarié par un « effet de ciseau » mettant en péril l’insertion des pays du sud de cette Méditerranée dans le processus de mondialisation. L’Europe a un rôle majeur à jouer dans cette région mais elle ne fait rien ou presque face à l’émergence des puissances asiatiques et latino-américaines. Si l’on attend qu’elle ait trouvé son «chemin de Damas», le risque est évident de voir à l’horizon 2030 disparaître la position centrale de l’Europe. Inversement, une projection raisonnable laisse prévoir un système global de commerce et de navigation centré sur l’océan Indien et les mers de Chine, les flux de trafics européens devenant graduellement périphériques dans une nouvelle circulation planétaire
Throughout the world globalisation exists as an everyday reality. Like many of our contemporaries, we are convinced that we are experiencing a completely new phenomenon. For the economic historian, talking about globalisation in the singular would mean ignoring all the others. It is not the purpose of this essay to deny the vigour of the current globalisation, but to grasp the size of a permanent phenomenon, which is now linked to containerisation. In fact, with the benefit of hindsight and a study of the past, we can understand better the current debates and possible future developments. But the future is largely determined by a certain number of change factors. If it is not possible to predict the final outcome of these changes, nonetheless, we can speculate on the way each might influence the future of the European economy, in general, and on the consequences which can result from the provision of containerised transport throughout Europe. Some of these factors can directly influence the strengths and weaknesses of the existing models; others can have indirect impacts.This thesis is an essay which is aimed at all the practitioners and university specialists interested in maritime trade. It is not a text about certitudes, nor a piece of condensed scholarship; the objective is neither to cover every aspect of maritime transport nor the economic history of Europe. Europe, which only represents 7% of the global land mass, is a peninsula bordered on three sides by the seas and does not have a neat geographical border on the fourth side separating it from the rest of the Eurasian continent. This geographical Europe has rarely coincided with an economic Europe. We must consider that the vast regions of east and south-east Europe were invaded and enslaved by non-European conquerors, and were liberated only after many centuries. In fact Europe has always had a variable geometry, which is normal, because, since ancient times it has been the result of all the different invasions and Eurasian trade. After the discovery of the American continent, Europeans developed commerce on a worldwide scale and imposed their hegemony until 1914. Spices and other oriental products were added to the products from the “East Indies”. This central position, obtained because of a demographic and technical superiority, stems from an economic and centralizing imperialism, challenged at the start of the 20th century and today largely condemned.With enormous transport capacities and very low costs, containerisation has accompanied globalisation for more than fifty years and has totally revolutionised the transport on regular lines of different merchandise. Henceforth, a permanent question about the globalisation of trade and navigation appears in different forms in this thesis; this is that access to the global market of Europe is certainly linked to the performance of European infrastructure but even more to global traffic. The future of Europe is inevitably linked to the Mediterranean and is thwarted by the “price scissors effect” which puts at risk the involvement of southern Mediterranean states in the process of globalisation. Europe has a major role to play in this region, but it does nearly nothing in response to the emergence of Asian and Latin American powers. If we wait for Europe to find its “road to Damascus”, there is a risk that by 2030 it will have lost its central role. On the other hand a reasonable prediction is that there will be a global system of trade and navigation centred on the Indian Ocean and the China seas, while European traffic gradually becomes peripheral to a new global containerised transport circulation

In questa tesi viene presentato un nuovo approccio per risolvere una classe di Radiative Transfer Problems, utilizzando la Theory of Connections. Il metodo prevede di risolvere in modo efficiente e accurato un problema lineare con una condizione al contorno (Linear One-Point Boundary Value Problem) derivante dall'equazione integro-differenziale di Boltzmann per il Radiative Transfer tramite un'espansione di polinomi di Chebyshev e metodo Least-Squares. L'algoritmo proposto risiede nella categoria dei metodi numerici per la soluzione delle equazioni del trasporto, ed è dimostrato essere accurato ed adatto per applicazioni nell'Atmospheric Science e Remote Sensing.

The transport sector accounts for a third of Sweden’s total greenhouse gas emissions where cars and heavy trucks dominate the use of fossil fuels. The Swedish government is now intensifying the work for an electrified transport sector where electric roads could be an important part. Electric roads enable heavy vehicles to charge their batteries while driving, which is expected to contribute to environmentally friendly and time-efficient freight transports. To implement electric roads, availability of electric power along the electric roads will be required. This study presents a plan for connecting an electric road to the electricity grid in the electricity network area of Vattenfall Eldistribution. From the results, the idea was to present general conclusions from the experiences of the study, that could contribute in further implementation of electric roads.  The road that has been selected for the study was the E4 between Gävle and Stockholm. A model for calculating the power demand along the electric road has been modeled and connection possibilities to transformer stations has been investigated. The analysis was based on three scenarios where different degrees of strengthening of the existing electricity network were assumed. In addition, a forecast for 2030 and a cost estimation for each scenario has been carried out. The result of the study indicates that for road sections close to larger cities, there are a larger number of connection options in comparison to rural areas. Furthermore, the designed solution in the study required strengthening of the electricity grid and the investment cost was 362 million Swedish crowns.

The transport sector accounts for a third of Sweden’s total greenhouse gas emissions where cars and heavy trucks dominate the use of fossil fuels. The Swedish government is now intensifying the work for an electrified transport sector where electric roads could be an important part. Electric roads enable heavy vehicles to charge their batteries while driving, which is expected to contribute to environmentally friendly and time-efficient freight transports. To implement electric roads, availability of electric power along the electric roads will be required. This study presents a plan for connecting an electric road to the electricity grid in the electricity network area of Vattenfall Eldistribution. From the results, the idea was to present general conclusions from the experiences of the study, that could contribute in further implementation of electric roads. The road that has been selected for the study was the E4 between Gävle and Stockholm. A model for calculating the power demand along the electric road has been modeled and connection possibilities to transformer stations has been investigated. The analysis was based on three scenarios where different degrees of strengthening of the existing electricity network were assumed. In addition, a forecast for 2030 and a cost estimation for each scenario has been carried out. The result of the study indicates that for road sections close to larger cities, there are a larger number of connection options in comparison to rural areas. Furthermore, the designed solution in the study required strengthening of the electricity grid and the investment cost was 362 million Swedish crowns.

Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains viii, 77 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 58-59).

Branching is a highly plastic trait, enabling plants to adapt their growth form in response to environmental stimuli. In flowering plants, shoot branching is regulated through the activity of axillary buds, which grow into branches. Several classes of plant hormones have been shown to play pivotal roles in regulating bud outgrowth. Auxin derived from the primary shoot apex and active branches inhibits bud outgrowth, whereas cytokinin promotes it. Strigolactones also inhibit bud outgrowth, by changing properties of the auxin transport network, increasing the competition between buds. This occurs by modulating access to the polar auxin transport stream (PATS) in the main stem. The PATS provides directional, long distance transport of auxin down the stem, involving basal localisation of the auxin transporter PIN-FORMED1 (PIN1). Buds need to export their auxin across the stem towards the PATS in order to activate, but since PIN1 is mainly expressed in narrow files of cells associated with the stem vasculature, PIN1 itself it is unlikely to facilitate this connectivity. This thesis re-examines the role of auxin transport in the stem, showing that, besides the PIN1-mediated PATS, other auxin transport proteins constitute a more widespread and less polar auxin transport stream, allowing auxin exchange between the PATS and surrounding tissues. Disruption of this transport stream is shown to reduce bud-bud communication and to partially rescue the increased branching observed in strigolactone mutants. Furthermore, it is shown that distinct classes of auxin transport proteins within this stream can differentially affect bud outgrowth mediated by BRANCHED1 (BRC1). BRC1 is a transcription factor proposed to determine bud activation potential. Taken together, the data presented here provide a more comprehensive understanding of the shoot auxin transport network and its role in shoot branching regulation.

The topic of this master‘s thesis was to create a settlement structure on the territory of the cadastral territory of the town of Náměšť nad Oslavou. Specifically in the southwestern part of the town, in the places of today's agricultural areas. The main goal of the thesis is to create a quality residential structure for the entire area, which will connect to the surrounding development, to create a center with urban amenities for this newly designed neighborhood. A key aspect of the design is the transport connection to the existing road network of the city and overcoming the barrier formed by the railway line. The proposed development responds to the current and future anticipated needs of the city. Taking into account the size, the proposed area is divided into three parts with regard to the time sequence and the nature of the development. From an urban point of view, the first phase builds on the existing network of streets and creates a transition between the original and the proposed development and proposes transport connections to the area. In the second and third phase, the remaining area of the proposed area is resolved, by a system of regular streets designed in places with a small slope of the terrain, connected by short streets with a higher slope. The master‘s thesis addresses the connection between the city and greenery, increases the attractiveness of the area by designing public facilities and services and works with visual axes from the existing housing and commercial development to the proposed location.

This dissertation addresses the reestablishment of the Hammanskraal train station, by providing an integrated transport node that includes a variety of community functions. The aim is to re-introduce the Stationarea as a signifi cant trade and transport node in the Hammanskraal community. The main routes linking to the railway station and the surrounding urban fabric are re-evaluated and altered to accommodate not only the railway programme, but also to better suit the growing needs of the community. Theoretically the project explores the infl uence architecture and spatial perceptions have on the social behaviour and the interactions between diff erent users in these spaces. These relationships are explored to create architecture that not only responds to existing conditions but also becomes a landmark in the area and a reference for future developments in the area. The theoretical investigation can be applied in a design such as the new Hammanskraal station as the characteristics and scope of this node need to integrate diff erent users and functions. Integrating these aspects into the design leads to new forms of interaction and spatial appropriation. The closure of the public component of the railway station resulted in the degradation and neglect of a site that is located within one of the busiest social and commercial nodes of the Hammanskraal Township. The suspended long distance commuter service in favour of the taxi and bus service has resulted in the lack of transport options to thousands of daily commuters between the township and the Pretoria CBD. The new Hammanskraal Railway interchange aims to reconnect the local residents, with a more economic means of travel, to the Pretoria CBD as most of them commute there for work opportunities. Integration and interaction between rail and road transport and numerous informal traders, within a vibrant urban space, are the main focus areas of the design. The design’s intent is to provide a reconnected township, while addressing the immediate needs of the site and the community. The redesign of the Hammanskraal Station precinct does not only reconnect the township to the railway system, but reintroduces much needed energy and public functions to the township itself while providing new economic opportunities both locally and in the surrounds.
Dissertation MArch(Prof)--University of Pretoria, 2012.
Architecture
MArch(Prof)
Unrestricted

Landscapes evolve through a number of processes in response to a wide range of forcing mechanisms. Many of the processes that drive landscape evolution occur at the interface between fluid and sediment. Sediment transport leads to changes in topography that, in turn, influence fluid flow. Feedback mechanisms between topography and fluid flow can lead to the formation of patterns, such as sand ripples, dune fields, parallel channel networks, and periodically spaced valleys. In many cases, the development and evolution of patterns within landscapes are heavily influenced by environmental conditions. Therefore, given relationships between landform features and the underlying processes, present-day landscapes have the potential to be used to infer a record of climatic conditions over the course of their development. An inability to make direct observations over geologically relevant timescales makes it difficult to study the processes that influence landscape evolution. Mathematical models provide a means of quantitatively linking natural patterns and landscape features with physical processes. Patterns in landscapes also provide a simple means of testing quantitative representations of geomorphic processes. In this work, we develop landscape evolution models to study the development of debris-flow-dominated hillslopes, rill networks, and cinder cones. Through a combination of theoretical modeling, analysis of experimental data, and remote sensing data, we attempt to better understand each of these three systems. While each system is interesting in isolation, these and similar studies add to our knowledge of the mathematical representations of processes that are used more generally within the study of landscape evolution.

Les travaux présentés dans ce mémoire ont été réalisés dans le cadre d’une collaboration entre le LAboratoire PLAsma et Conversion d’Énergie (LAPLACE), Université de Toulouse, et la Seconde Université de Naples (SUN). Ce travail a reçu le soutien de la société Rongxin Power Electronics (Chine) et traite de l’utilisation des convertisseurs multi-niveaux pour le transport d’énergie électrique en courant continu Haute Tension (HVDC). Depuis plus d’un siècle, la génération, la transmission, la distribution et l’utilisation de l’énergie électrique sont principalement basées sur des systèmes alternatifs. Les systèmes HVDC ont été envisagés pour des raisons techniques et économiques dès les années 60. Aujourd’hui il est unanimement reconnu que ces systèmes de transport d’électricité sont plus appropriés pour les lignes aériennes au-delà de 800 km de long. Cette distance limite de rentabilité diminue à 50 km pour les liaisons enterrées ou sous-marines. Les liaisons HVDC constituent un élément clé du développement de l’énergie électrique verte pour le XXIème siècle. En raison des limitations en courant des semi-conducteurs et des câbles électriques, les applications à forte puissance nécessitent l’utilisation de convertisseurs haute tension (jusqu’à 500 kV). Grâce au développement de composants semi-conducteurs haute tension et aux architectures multicellulaires, il est désormais possible de réaliser des convertisseurs AC/DC d’une puissance allant jusqu’au GW. Les convertisseurs multi-niveaux permettent de travailler en haute tension tout en délivrant une tension quasi-sinusoïdale. Les topologies multi-niveaux classiques de type NPC ou « Flying Capacitor » ont été introduites dans les années 1990 et sont aujourd’hui couramment utilisées dans les applications de moyenne puissance comme les systèmes de traction. Dans le domaine des convertisseurs AC/DC haute tension, la topologie MMC (Modular Multilevel Converter), proposée par le professeur R. Marquardt (Université de Munich, Allemagne) il y a dix ans, semble particulièrement intéressante pour les liaisons HVDC. Sur le principe d’une architecture de type MMC, le travail de cette thèse propose différentes topologies de blocs élémentaires permettant de rendre le convertisseur AC/DC haute tension plus flexible du point de vue des réversibilités en courant et en tension. Ce document est organisé de la manière suivante. Les systèmes HVDC actuellement utilisés sont tout d’abord présentés. Les configurations conventionnelles des convertisseurs de type onduleur de tension (VSCs) ou de type onduleur de courant (CSCs) sont introduites et les topologies pour les systèmes VSC sont ensuite plus particulièrement analysées. Le principe de fonctionnement de la topologie MMC est ensuite présenté et le dimensionnement des éléments réactifs est développé en considérant une commande en boucle ouverte puis une commande en boucle fermée. Plusieurs topologies de cellules élémentaires sont proposées afin d’offrir différentes possibilités de réversibilité du courant ou de la tension du côté continu. Afin de comparer ces structures, une approche analytique de l’estimation des pertes est développée. [...]
This work was performed in the frame of collaboration between the Laboratory on Plasma and Energy Conversion (LAPLACE), University of Toulouse, and the Second University of Naples (SUN). This work was supported by Rongxin Power Electronic Company (China) and concerns the use of multilevel converters in High Voltage Direct Current (HVDC) transmission. For more than one hundred years, the generation, the transmission, distribution and uses of electrical energy were principally based on AC systems. HVDC systems were considered some 50 years ago for technical and economic reasons. Nowadays, it is well known that HVDC is more convenient than AC for overhead transmission lines from 800 - 1000 km long. This break-even distance decreases up to 50 km for underground or submarine cables. Over the twenty-first century, HVDC transmissions will be a key point in green electric energy development. Due to the limitation in current capability of semiconductors and electrical cables, high power applications require high voltage converters. Thanks to the development of high voltage semiconductor devices, it is now possible to achieve high power converters for AC/DC conversion in the GW power range. For several years, multilevel voltage source converters allow working at high voltage level and draw a quasi-sinusoidal voltage waveform. Classical multilevel topologies such as NPC and Flying Capacitor VSIs were introduced twenty years ago and are nowadays widely used in Medium Power applications such as traction drives. In the scope of High Voltage AC/DC converters, the Modular Multilevel Converter (MMC), proposed ten years ago by Professor R. Marquardt from the University of Munich (Germany), appeared particularly interesting for HVDC transmissions. On the base of the MMC principle, this thesis considers different topologies of elementary cells which make the High Voltage AC/DC converter more flexible and easy suitable respect to different voltage and current levels. The document is organized as follow. Firstly, HVDC power systems are introduced. Conventional configurations of Current Source Converters (CSCs) and Voltage Source Converters (VSCs) are shown. The most attractive topologies for VSC-HVDC systems are analyzed. The operating principle of the MMC is presented and the sizing of reactive devices is developed by considering an open loop and a closed loop control. Different topologies of elementary cells offer various properties in current or voltage reversibility on the DC side. To compare the different topologies, an analytical approach on the power losses evaluation is achieved which made the calculation very fast and direct. A HVDC link to connect an off-shore wind farm platform is considered as a case study. The nominal power level is 100 MW with a DC voltage of 160 kV. The MMC is rated considering press-packed IGBT and IGCT devices. Simulations validate the calculations and also allow analyzing fault conditions. The study is carried out by considering a classical PWM control with an interleaving of the cells. In order to validate calculation and the simulation results, a 10kW three-phase prototype was built. It includes 18 commutation cells and its control system is based on a DSP-FGPA platform

The G-protein coupled receptor (GPCR) Cysteine (C)-X-C Receptor 4 (CXCR4) plays an important role in prostate cancer metastasis. CXCR4 is regarded as a plasma membrane receptor, that it transmits signals that support transformation, progression and metastasis. Due to the central role of CXCR4 in tumorigenesis, therapeutic approaches such as antagonists and monoclonal antibodies have focused on receptors the located at the plasma membrane. An emerging concept for GPCRs is that they can localize to the nucleus where they may retain function and mediate nuclear signaling. Herein, we demonstrate that CXCR4 is highly expressed in high grade metastatic prostate cancer tissues. Increased expression of CXCR4 is also detected in several prostate cancer cell lines as compared to normal prostate epithelial cells. Our studies identify a nuclear pool of CXCR4 and also define a mechanism for nuclear targeting of CXCR4. A classical nuclear localization sequence (cNLS), "RPRK", in CXCR4 can contribute to nuclear localization. In addition, CXCR4 interacts with the nuclear transport receptor, Transportin βi, to promote nuclear accumulation of CXCR4. Importantly, Gαi immunoprecipitation and calcium mobilization studies indicate that nuclear CXCR4 is functional and can participate in G-protein signaling revealing that the nuclear pool of CXCR4 can retain function. Localization of functional CXCR4 to the nucleus may be a mechanism by which prostate cancer cells evade treatment, thus contributing to increased metastatic ability and poorer prognosis after tumors have been treated with therapy that targets plasma membrane CXCR4. This study addresses the mechanism of nuclear targeting for CXCR4 and demonstrates that CXCR4 can retain function within the nucleus and provides important new information to illuminate what have previously been primarily clinical observations of nuclear CXCR4.

Orientador: Antonio Padilha Feltrin
Abstract: In recent years, the use of electric vehicles in urban zones has been intensified. As a policy of increasing the penetration of electric vehicles and reducing air pollution, electric taxis have been introduced into transportation systems. They need special attention because of its different driving patterns. In contrast to private electric vehicles, which can be recharged for a long period, electric taxis need to recharge only for a short time due to their constant operation. Therefore, fast charging stations are required to meet the demand for recharging electric taxis and should be located at strategic places. In addition, an analysis must be performed to connect these stations in the electric network. To improve their allocation and connectivity, this work presents a methodology to help in decision making for installing fast charging stations, considering as criteria: locations with greater flow of electric taxis and low level of state of charge, the available physical space to carry out their recharge and cost functions for the connection of charging stations. The result of the proposal is a map with the location of fast charging stations and analysis of the lowest cost places for connection to the network. The methodology is tested in a medium-sized city in Brazil, showing the importance of this map and cost functions in decision making. The proposal is compared with another methodology, showing that the proposed method considers different criteria and creates a better s... (Complete abstract click electronic access below)
Resumo: Nos últimos anos, o uso dos veículos elétricos nas zonas urbanas tem se intensificado. Como política para o aumento na penetração de veículos elétricos e reduzir a poluição do ar, os táxis elétricos vem sendo introduzidos nos sistemas de transporte. Eles necessitam de atenção especial devido aos seus diferentes padrões de condução. Em contraste com os veículos elétricos privados, que podem ser recarregados por um longo período, táxis elétricos necessitam de recarga em um curto período de tempo devido a sua constante operação. Portanto, estações de recarga rápida são necessárias para receber a demanda de recarga dos táxis elétricos e devem estar localizadas em locais estratégicos. Além disso, uma análise deve ser realizada para a conexão destas estações com a rede elétrica. Para melhorar sua alocação e conectividade, este trabalho apresenta uma metodologia para auxiliar na tomada de decisão da instalação de estações de recarga rápida considerando como critérios: locais com maior fluxo de táxis elétricos e baixo nível de carga nas baterias, espaço físico disponível para realizar o carregamento e funções de custo para a conexão das estações de recarga. Os resultados da proposta são mapas com a localização das estações de recarga rápida e análise dos locais de menor custo para a conexão com a rede elétrica. A metodologia é testada em uma cidade de médio porte no Brasil, mostrando a importância dos mapas e funções de custo na tomada de decisão. A proposta é comparada com outras me... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

The object of this Thesis is an area adjacent to European heritage site of Dolni Vitkovice, in the city of Ostrava, Moravian-Silesian Region. This work focuses on making the area more accessible by all means of transportation, overcoming natural and man-made barriers as well as exploring the possibility of dense development on the site while maintaining its industrial identity. All that in context of otherwise slowly shrinking post-industrial city with aging and declining urban population.

Ce travail de thèse étudie de nouvelles configurations d'alimentation de commande rapprochée et un nouveau concept de packaging afin d'améliorer les performances des MOSFETs SiC connectés en série. Les nouvelles configurations de commande rapprochée sont proposées afin de réduire les courants de bruit qui circulent dans la partie commande du système électrique. De plus, une nouvelle alimentation de commande de grille est proposée pour augmenter le dv / dt de la cellule de commutation. Ces améliorations, c'est-à-dire la réduction du courant de bruit et l'amplification du dv/dt, sont obtenues en modifiant l'impédance des circuits de commande de grille. Le nouveau concept de packaging est proposé afin d'améliorer les performances d’équilibrage de tension. Les nouvelles configurations de commande rapprochée et les concepts de packaging sont introduits et analysés grâce à des modèles analytique et des simulations. Ensuite, des essayes expérimentales sont effectuées pour confirmer que les concepts proposés sont meilleurs que les concepts traditionnels en termes d'équilibrage de tension, de vitesse de commutation et de réduction EMI conduite
This work investigates new gate drive power supply configurations and a novel multi-steppackaging concept in order to improve the performance of series-connected SiC-MOSFETs. The new gate drive configurations are proposed in order to reduce noise currents that circulate in the control part of the electrical system. Furthermore, a new gate drive power supply is proposed to increase the dv/dt of the switching cell. These improvements, i.e., noise current reduction and dv/dt boosting, are achieved by modifying the impedance of the gate drive circuitry. The novel multi-step packaging concept is proposed in order to improve the voltage sharing performance. The proposed package geometry considers optimal dielectric isolation for each device leading to a multi-step geometry. It has a significant impact on the parasitic capacitances introduced by the packaging structure that are responsible for voltageunbalances. The new gate driver configurations and the proposed multi-step packaging concepts are introduced and analysed thanks to equivalent models and time domain simulations. Then, experimental set-ups are performed to confirm that the proposed concepts are better than traditional ones in terms of voltage balancing, switching speed and conducted EMI reduction

Esta dissertação tem como objetivo discutir sob quais condições uma G- estrutura é integrável. Primeiro apresentam-se fibrados principais, vetoriais e outras estruturas a elas associados como torção, espaços verticais, espaços horizontais e conexões. Depois apresentam-se a definição de G-estrutura, de integrabilidade de G-estruturas, com exemplos e as respectivas versões de integrabilidade e equivalência de G-estruturas. Finalmente, são descritas condições mais gerais que garantem a integrabilidade de G-estruturas.
This dissertation aims to discuss what are the conditions for the inte- grability of a G-structure. We begin presenting principal bundles, vectoer bundles, associated bundles and other structures related to them like torsion, vertical spaces, horizontal spaces and connections. After this, we present the definition of G-structure, integrability os G-structures with examples ans respectives versions of integrabilities and the equivalence of G-estructures. Finally, we describe more general conditions that ensure the integrability of G-structures.

The insulin-like growth factor-1 receptor (IGF-1R) and many of its downstream signaling components have long been implicated in tumor progression and resistance to therapy. The insulin receptor substrate-1 (IRS-1) and IRS-2 adaptor proteins are two of the major downstream signaling intermediates of the IGF-1R. Despite their considerable homology, previous work in our lab and others has shown that IRS-1 and IRS-2 play divergent roles in breast cancer cells. Signaling through IRS-1 promotes cell proliferation, whereas signaling through IRS-2 promotes cell motility and invasion, as well as glycolysis. Moreover, using a mouse model of mammary tumorigenesis, our lab demonstrated that IRS-2 acts as a positive regulator of metastasis, while IRS-1 cannot compensate for this function. The focus of my thesis research is to understand how IRS-2, but not IRS-1, promotes breast carcinoma cell invasion and metabolism to support metastasis. In preliminary studies, I have found that IRS-1 and IRS-2 exhibit different expression patterns in both cell lines and human tumors with correlations to patient survival, which provides a potential mechanism for their distinct functions. The localization of IRS-1 and IRS-2 within separate intracellular compartments would determine their access to downstream effectors and substrates, and this would result in unique cellular outcomes. Specifically, I have observed that IRS-2, but not IRS-1, co-localizes with microtubules in breast carcinoma cell lines with implications for signaling through AKT and mTORC2. The goal of this research is to determine how the localization of IRS-2 contributes to its regulation of breast cancer progression and response to therapy and how this information could be used to better predict patient outcomes.

Dans le contexte de la montée des préoccupations écologiques, le développement de véhicules de transports routiers s’oriente vers le développement de véhicules moins polluants à entraînement électrique comme les Véhicules Électriques Hybrides (VEHs) et les Véhicules tout Électriques (VEs). Avec l’augmentation des puissances requises et la réduction de l’espace disponible, la gestion thermique devient une préoccupation de plus en plus importante lors du développement des composants embarqués comme les moteurs/générateurs électriques, onduleurs, batteries et faisceaux électriques. Parmi eux, le faisceau électrique de puissance qui est typiquement composé de câbles électriques, de connecteurs et de boîtes de distribution de puissance ne peut être conçu de manière appropriée qu’à la suite d’une analyse thermique, électrique, chimique et mécanique approfondie.Cette thèse est écrite pour contribuer à l’optimisation de la conception électrothermique de faisceaux de câbles par des simulations afin de réduire la quantité de tests expérimentaux nécessaires pour leur développement. Des modèles théoriques pour la prédiction du comportement électrique et thermique de câbles électriques et des faisceaux de câbles sont passés en revue et adaptés aux exigences automobiles. La validation est accomplie en comparant les résultats de simulation avec ceux d’analyses élément finie (FEA) et de données de mesure. Une partie majeure de cette thèse aborde la simulation thermique de câbles électriques de longueur infinie suspendus dans l’air, prenant en compte les dépendances en température des résistances de conducteurs et la non-linéarité du coefficient de transfert thermique total à la surface du câble. L’influence des courants de blindage et de courants arbitraires dans les conducteurs sur la montée en température des câbles électriques est considérée dans des circuits thermiques équivalents et illustré par des exemples pratiques
In the context of growing ecological concerns, the development of road transport vehicles moves itself toward the development of less polluting vehicles with electric drives such as Hybrid Electric Vehicles (HEVs) and full Electric Vehicles (EVs). With rising power requirements and reducing available space, thermal management is becoming an increasingly important concern during development of on-board vehicle components such as electric motor(s)/generator(s), power inverter(s), battery pack(s) and cable harnesses. Among them, the cable harness which is typically composed of electrical cables, connectors and power distribution boxes can only be designed properly after a detailed thermal, electrical, chemical and mechanical analysis.This thesis is written to contribute to the optimization of the electro-thermal design of cable harnesses through simulations and reduce the amount of experimental testing needed during their development. Theoretical models for the prediction of the electrical and thermal behavior of electric cables and cable harnesses are reviewed and adapted for automotive requirements. Validation is accomplished by comparing simulation results with Finite Element Analysis (FEA) and measurement data. A major part of this thesis addresses the thermal simulation of electrical cables of infinite length installed in air, taking into account the temperature dependencies of conductor resistances and non-linearity of the total heat transfer coefficient at the cable surface. The influence of shielding currents and arbitrary current loads in the conductors on the temperature rises within electric cables is also considered using thermal ladder networks and illustrated by practical examples. Because shielding currents in vehicles are not only caused by induced currents but also by functional electrical currents generated by low-voltage power sources, new theoretical studies and experimental observations for the estimation of these currents as a function of the vehicle electrical architecture and circuit characteristics are presented. A primary finding reveals that keeping the resistance of grounding connections low compared to that of the shielding connections is an appropriate but expensive means for limiting the transfer of functional currents in the shielding circuits. Finally, a complete and modular model for the prediction of transient temperatures along the length of cable harness sections is developed and validated based on the outcomes of all previous findings

This thesis questions a series of assumptions concerning the nineteenth- and early-twentieth-century modernization of European spaces. Current scholarship tends to concur with essayistic texts and images by contemporary intellectuals that technological and organizational developments increased the freedom of movement of those living in western-European societies, while at the same time alienating them from each other and from their environment. I assess this claim with the help of Dutch travel egodocuments such as travel diaries and letters. After a prosopographical investigation of all available northern-Netherlandish travel egodocuments created between 1500 and 1915, a selection of these documents is examined in greater detail. In these documents, travellers regarded the possession of identity documents, a correct appearance, and a fitting social identity along with their personal contacts, physical capabilities, and the weather as the most important factors influencing whether they managed to gain access to places. A discussion of these factors demonstrates that no linear increase, nor a decrease, occurred in the spatial power felt by travellers. The exclusion many travellers continued to experience was often overdetermined. The largest groups affected by this were women and less educated families. Yet travellers could also play out different access factors against each other. By paying attention to how practices matched hopes and expectations, it is possible to discover how gravely social inequities were really felt by travellers. Perhaps surprisingly, all social groups desired to visit the same types of places. Their main difference concerned the atmosphere of the places where the different groups felt at home. To a large degree this matched travellers' unequal opportunities. Therefore, although opportunities remained strongly unequal throughout the period, this was not always experienced as a problem. Also, in cases where it was, many travellers knew strategies to work around the obstacles created for them.

Le port de Paris ne correspond pas à la définition traditionnelle du terme. On doit observer tout d'abord qu'il s'agit d'un port fluvial. La difficulté de définir le port de Paris tient au fait qu'il consiste en plusieurs types d'installations: canaux, ports à darses, ports sur berges (quais droits et ports de tirage) et donc à des réalités protéiformes. Certains auteurs préfèrent l'expression« ports de Paris», pour en souligner le caractère hétéroclite. Au XIXe siècle, on parlait également des «ports de Paris», c'est-à-dire des installations sur la Seine, par opposition aux canaux. Le port de Paris correspond donc à un ensemble bordé par une soixantaine de kilomètres de rives, dont une partie destinée à la batellerie. La thèse débute à une époque durant laquelle le transport fluvial se trouve confronté aux effets de la concurrence des chemins de fer. Il lui faudra plusieurs décennies pour s'adapter et revêtir une nouvelle fonction, à savoir celle quasi exclusive de pourvoyeuse de pondéreux. Cette conversion s'est opérée essentiellement à travers l'amélioration des infrastructures fluviales. La modernisation portuaire revêtait deux volets, à savoir l'amélioration de l'outillage en vue d'optimiser le conditionnement des marchandises, et celle appartenant à une vision plus globale de la fonction du port de Paris, voire de Paris lui-même. Paris port de mer appartient à cette dernière. On peut avancer l'idée d'une opposition entre un «port réel» et un port «mythique», à savoir une voie alternative visant à transformer la vocation portuaire de la capitale. Des tentatives de réconciliation entre les deux visions se manifestent à travers la création du port d’Ivry, des commissions entre 1911 et 1914 sur la modernisation de l'outillage portuaire
The Port of Paris does not correspond to the traditional definition of the term. It should first be noted that this is a river port. The difficulty of defining the port of Paris stems from the fact that it consists of several types of installations: canals, ports at docks, ports on banks (straight wharves and pull ports) and therefore protean realities. Some authors prefer the term "ports of Paris" to emphasize its heterogeneous character. In the 19th century, we also talked about the "ports of Paris", that is to designate installations on the Seine, as opposed to canals. The port of Paris thus corresponds to an ensemble bordered by some sixty kilometers of shore, including a part intended for inland navigation This thesis begins at a time when river transport is confronted with the effects of competition from the railways. It will take several decades to adapt and take on a new function, namely the almost exclusive role of provider of weighty. This conversion was mainly achieved through the improvement of river infrastructures. Port modernization had two aspects: improving tooling to optimize the packaging of goods, and integrating a more global vision of the function of the port of Paris, and even of Paris itself. "Paris sea port" belongs to the latter. One can put forward the idea of an opposition between a "real port" and a "mythical" port, an alternative way of transforming the port's vocation to the capital. Attempts at reconciliation between these two visions are manifested through the creation of the port of Ivry, commissions between 1911 and 1914 on the modernization of port equipment

South Africa boasts such intrinsic beauty in its social and physical geography and at the heart of this beauty lie its people. For each culture that has fought for their beliefs and systems, wars have been fought and lives have been lost. One thing which remains constant however is the belief that we the people can work together to live in peace and harmony and leave a better place to those who come after. Apartheid South Africa was divisive in many ways and its results have left many wounds on the country’s architectural geography. Social inequality is manifest in the tapestry of everyday life and the Peri-Urban scars of our past have become vivid thresholds of crosscultural debate. The Apartheid planning model of disconnection through race and class has seen a massive effort to refocus on Durban’s urban core, whereas the rich tapestry of the Peri-Urban townships is often neglected. In order to reconnect the outer city geographies back into the urban whole an investigation into the theory of connection between people and their physical environment needs to be undertaken. This dissertation looks at how the theory of connection might enable a unified Durban and rehabilitate the tenderness of past planning processes. Public Transport is one such mechanism which can connect communities, no matter the distance nor socio-economic status and it is within this context that the dissertation offers new insight into the critical and exciting reconnection process.
M. Arch. University of KwaZulu-Natal, Durban, 2013.

The implementation of new public transport networks, such as the Gautrain, present new responsibilities and opportunities for urban development. Mega projects like these are constructed for various economical, social and political reasons. These underlying orders beg a necessary question when defining the architectural program required for the integration of the stations and there relative contexts. Integration is a key narrative for the exploration and enquiry of this thesis. The new Gautrain system should connect with existing and future transport systems, social systems and other contextual realities. Another question raised throughout the theoretical enquiry of this thesis is; to what extent does this connection and integration occur at the recently completed Gautrain stations? The idea of creating ‘Gateways’ into a city, rather than mere station ‘posts’ is explored as an architectural narrative. These ‘Gateways’ become the introductory point for commuters and an opportunity to create an experiential dimension relating to ‘the image of a city’ and its ‘zeitgeist’. Pretoria Station was chosen due the many layers of integration intrinsic to the site. This opportunity is available due to the existence of neo‐classical buildings within the immediate and macro context. Here the application of a contemporary, 21st century piece may create a representation of the progression of architectural and sociological thinking, relating to city building and transportation. This site also offers opportunities for exploring the integration of existing and future transport networks due to the existence of several of transport modes. Theories of city building and ‘placemaking’ are explored as a requirement borne out of the neglect for this site as it has developed through the modern era.

Thesis (M. Sc.)--University of Alberta, 2009.
Title from PDF file main screen (viewed on Dec. 1, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Electrical and Computer Engineering, University of Alberta." Includes bibliographical references.

Hydrodynamic slip is known to suppress vorticity production at the solid-fluid boundary in bluff body flows. This suppression combined with the enhanced vorticity convection results in a substantial reduction in the unsteady vortex shedding and the hydrodynamic loads experienced by the bluff body. Here, using combined theoretical and computational techniques, we investigate the effect of slip on three-dimensional wake dynamics and convective scalar transport from a circular cylinder placed in the uniform cross-flow of a Newtonian incompressible fluid over Reynolds numbers ranging from 0.1 to 1000. We find the wake patterns to be strongly influenced by the degree of the slip, quantified through the non-dimensional slip length in the Naiver slip model, with the asymptotic slip lengths of zero and infinity characterizing no-slip and no-shear boundaries, respectively. With increasing slip length, the wake three-dimensionality, that is observed in the case of a no-slip surface for Re > 190, is gradually suppressed and eventually eliminated completely. For each Reynolds number, we identify the critical slip length beyond which the three-dimensionality is completely suppressed and the wake becomes two-dimensional, on the basis of the total transverse entropy present in the flow field. Over the Reynolds number range considered in this work, we find the critical slip length to be an increasing function of Reynolds number. For sufficiently large slip lengths, we observe suppression of two-dimensional vortex shedding leading to formation of a steady separated wake. Further increments in slip length lead to reduction in the intensity and size of the recirculating eddy pair eventually resulting in its complete disappearance for a no-shear surface for which the flow remains attached all along the cylinder boundary. Next, we quantify the effect of hydrodynamic slip on convective transport from an isothermal circular cylinder placed in the uniform cross flow of an incompressible fluid at a lower temperature. For low Reynolds and high P´eclet numbers, theoretical analysis based on Oseen and thermal boundary layer equations allows us to obtain explicit relationships for the dependence of transport rate on the prescribed slip length. We observe that the non-dimensional transport coefficients follow a power law scaling with respect to the P´eclet number, with the scaling exponent increasing gradually from the lower asymptotic limit of 1/3 for the no-slip surface to 1/2 for a no-shear boundary. Results from our simulations at finite Reynolds number indicate that the local time-averaged transport rates for a no-shear surface exceed the one for the no-slip surface all along the cylinder except in the neighbourhood of the rear stagnation region, where flow separation and reversal augment the transport rates substantially.

博士
國立清華大學
分子醫學研究所
107
Microtubule (MT) arrays are dramatically reorganized from nest‐like structures into anti‐parallel ones during dorsal closure (DC) in Drosophila embryos. In addition to its function in dorsal most epithelial (DME) cells for promoting fillopodia formation (Jankovics and Brunner, 2006), MTs are reported to be involved in the intercellular transport (IT) of adherens junction (AJ) protein-containing intercellular endosomes (IEs) in those lateral epithelial (LE) cells (Li et al., 2015); however, the underlying mechanism is poorly understood. By live imaging and immuno-histochemical (IHC) staining, both the synthesizing MTs (EB1) and acetylated MTs (Ac-MTs) were found to be able to pierce through "pore-like" structures on plasma membrane (PM) at AJs. The "GFP belt" resulted from signal combination from AJ and SJ markers revealed the existence of novel AJ-associated pores on the PM of LE cells, which allowed the IT. Analysis with photo-activatable GFP (C3PA-GFP) and cell lineages labeling experiments suggested cytoplasmic connections among neighboring LE cells that were independent of ring canals or cell lineages. Optogenetic dimerization between the Kinesin and Echinoid (Ed) suggested the role of MTs as tracks in the transport of IEs. TEM images implied the instability of AJ membrane during DC upon conjugating with MTs and also the possible structure for AJ-associated pores with vesicle-decorated MTs in the lumen. Consistent with what have been suggested in mammalian cells, cadherin complexes and several MT‐associated proteins were also required for the embracement and rearrangement of MT arrays, and therefore were concerned as the “capturers” for MTs by stabilizing them at the cell cortex near AJs. According to the results, we suggested a hypothetic model for the AJ-associated pores and the MT-dependent IT : MT arrays are rearranged and relocated to the AJs during DC. The association among MTs and AJs leads to local lipid instability, which might benefit the formation of nascent AJ-associated pores. After further expansion and stabilization, acetylated MT arrays may act as the tracks for the synthesizing MTs to grow along and across the "pores" without being captured, and thereby allow the IT of IEs and the cytoplasmic connections.