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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Géographie de la libéralisation du transport aérien passagers en Europe / Geography of liberalisation in the european passenger aviation market

Dobruszkes, Frédéric 22 May 2007 (has links)
De 1987 à 1997, le transport aérien intra-européen a connu un bouleversement institutionnel sans précé-dent avec sa libéralisation, c’est-à-dire le passage d’un environnement très régulé et contraint par les États à un environnement libéral. Au terme de ce processus, toute compagnie communautaire peut opérer n’importe quel vol intra-communautaire et les aides d’État sont interdites, obligeant les compagnies à être financière-ment rentables. La liberté d’accès au marché et l’impératif de rentabilité sont de nature à faire évoluer la géographie des réseaux et donc la desserte des ré-gions européennes par le biais de différentes dynami-ques (développement ou rationalisation des compagnies préexistantes, émergence de nouvelles compagnies, faillites, réorganisation des services publics,…).<p>La libéralisation du ciel européen a effectivement conduit à soumettre l’essentiel de l’offre intra-européenne aux « lois du marché », les services publics étant devenus résiduels (moins de 5% des sièges intra-européens). Pour autant, la concurrence à l’échelle des lignes n’est pas devenue la norme. Elle a certes aug-menté, en particulier sur des grandes lignes domesti-ques jadis très protégées, sur les principales lignes européennes entre régions métropolitaines et sur les lignes nord – sud à vocation touristique. Cependant, le développement de nombreuses nouvelles lignes exploi-tées par une seule compagnie a paradoxalement aug-menté le nombre et la part des monopoles de fait. De nombreuses concurrences n’ont lieu qu’indirectement, soit au travers de filiales étrangères (par exemple Spa-nair appartenant à SAS), soit par des compagnies low-cost opérant depuis des aéroports secondaires plus éloignés des grandes agglomérations européennes (par exemple Hahn au lieu de Francfort).<p>Entre 1991 et 2005, la desserte de l’espace européen libéralisé connaît d’importantes évolutions. D’une part, le volume de l’offre (en sièges) est presque multiplié par deux (+85%, +81% si l’on se limite aux vols intra-européens), soit un taux de croissance annuel moyen de 5,6%. Cette croissance concerne plus l’offre interna-tionale que nationale, qui l’emporte maintenant sur la seconde. D’autre part, la dynamique d’ouverture et de fermeture de lignes est spectaculaire :1308 créations contre 459 disparitions, si bien que le nombre total de lignes a augmenté de moitié et que le réseau européen actuel est un réseau pour moitié renouvelé par rapport à celui de 1991. Cependant, le poids en sièges des lignes héritées est de 8/10. Le réseau européen actuel est donc quantitativement toujours dominé par les relations historiques, qui constituent l’armature de la desserte aérienne européenne.<p>Les espaces touristiques balnéaires méridionaux ont capté une grande partie de cette croissance (3/10 des nouvelles liaisons, ¼ de l’augmentation générale du nombre de sièges). Si l’on y ajoute le tourisme urbain, on observe très clairement une banalisation du tou-risme aérien.<p>Une typologie évolutive des réseaux à l’échelle des compagnies a révélé des stratégies différenciées et donc des impacts variés en termes de desserte des territoires. Les grandes compagnies nationales ont généralement fortement développé leur offre tout en la concentrant plus encore sur leurs bases aéroportuaires traditionnelles organisées en hubs. Parfois, un second hub a dû être créé pour contourner des problèmes de saturation (Munich en plus de Francfort) ou mieux coller à la demande (Milan en plus de Rome). Les compagnies classiques ont aussi pris des participations dans des petites compagnies afin de pénétrer plus facilement, et à moindre coût, des marchés étrangers. Ces filiales — et leurs réseaux — ont parfois été converties en opéra-teurs régionaux alimentant les grands hubs. Par ail-leurs, diverses petites compagnies ont pu se développer à l’échelle européenne, sortant souvent de leur cadre national classique. Ces développements se sont tantôt faits au bénéfice des villes « de province » (en particu-lier en Grande-Bretagne), tantôt par concentration sur la capitale (en particulier dans les pays où les villes de province ont peu de poids économique et démographi-que). Enfin, des compagnies charters ont transformé leur offre en offre régulière, la rendant plus ouverte au public, au profit des zones touristiques méridionales qui sont ainsi plus facilement accessibles.<p>Mais la plus spectaculaire évolution est sans doute le développement des compagnies low-cost. Celles-ci sont responsables de 4/10 de la croissance de l’offre (en sièges) sur la période 1995-2004 ;elles sont aussi mêlées à 3/10 des nouvelles lignes européennes ouver-tes entre 1991 et 2005. Leurs réseaux renforcent les liaisons entre régions métropolitaines et entre celles-ci et les destinations touristiques. En outre, les régions subcentrales leur doivent la moitié de leur desserte et presque toute leur croissance. De nombreux petits aéroports leur doivent l’essentiel, voire la totalité, de leur desserte et de leur croissance, en particulier dans les régions subcentrales et intermédiaires. Ceci a consi-dérablement modifié les rapports entre compagnies et gestionnaires d’aéroports, plaçant ces derniers dans un rapport de forces qui ne leur est pas toujours favorable.<p>Ces dynamiques viendraient presque faire oublier les décroissances. D’une part, des faillites ont parfois eu un effet négatif marqué sur la desserte des villes, comme nous l’avons en particulier montré pour Bruxelles avec la faillite de la Sabena. D’autre part, les services publics subventionnés semblent être en régression, bien que l’analyse détaillée du cas français montre que la géo-graphie des services publics antérieurs à la libéralisation découlait parfois plus d’exigences politiques locales que de besoins réels.<p>A l’échelle régionale, l’analyse des évolutions par types économiques régionaux montre qu’au-delà de taux de croissance très variés et malgré toutes les dynamiques étudiées, la répartition de l’offre est demeurée assez constante :il n’y a pas de remise en cause de la hiérar-chisation de l’espace européen. Les régions métropoli-taines continuent en effet à polariser une très grande partie de l’offre et sont toujours les points de passage quasi-obligés pour les vols intercontinentaux. Un niveau en dessous, les régions centrales disposent toujours d’une offe honorable, quoique limitée à l’Europe et ses marges. Les régions subcentrales profitent d’une « décompression » des régions métropolitaines et cen-trales et de la dynamique low-cost. Les capitales des pays ex-communistes connaissent un rattrapage et sont repolarisées par l’Europe occidentale. Les périphéries touristiques connaissent un important développement mais pèsent peu globalement. Les autres périphéries et les espaces intermédiaires tendent à se marginaliser, victimes de trop faibles densités économiques et démo-graphiques et d’une contraction des services publics aériens.<p>Enfin, si le développement de lignes transversales entre petites villes est une réalité, leur poids est avant tout local. Celles-ci pèsent en effet peu globalement. <p> / Doctorat en sciences, Spécialisation géographie / info:eu-repo/semantics/nonPublished
22

[pt] O CONCEITO DE EIXO ENQUANTO ESPACIALIDADE SOCIAL: COMPREENDENDO SEUS SENTIDOS E SUA HISTORICIDADE / [en] THE CONCEPT OF AXIS AS A SOCIAL SPATIALITY: UNDERSTANDING ITS MEANINGS AND ITS HISTORICITY

MATHEUS CAVALCANTI BARTHOLOMEU 18 May 2021 (has links)
[pt] O objetivo deste trabalho é compreender criticamente a história do conceito de eixo como referente a uma espacialidade social, elucidando sua gênese e seu devir pela investigação das trajetórias de seus principais sentidos e funções. Trata-se de um conceito cada vez mais pertinente para a geografia e as demais ciências preocupadas com o espaço social, porque permite compreender mais precisamente a relação entre espaço e circulação. Para responder ao problema de pesquisa ― Quais são a gênese do conceito de eixo e os fundamentos de seu devir histórico e o que este devir aponta como possibilidades ainda não plenamente realizadas? ―, adotamos um cruzamento entre os métodos da história conceitual desenvolvida por Reinhart Koselleck e uma abordagem baseada no método regressivo-progressivo empreendido por Karl Marx e elucidado por Henri Lefebvre e Jean-Paul Sartre. Com base nesse cruzamento, a pesquisa começa por uma reconstituição dos usos e significações recentes de eixo amparada na ideia de que os conceitos podem apresentar sentidos analíticos, sentidos normativos e sentidos da prática. Primeiro, observamos a instrumentalização do conceito de eixo pelo planejamento territorial, ancorada no imperativo da neoliberalização e o imperativo da fluidez. Em seguida, examinamos a influência do conceito normativo de eixo no âmbito científico, percebendo reproduções críticas e acríticas desses sentidos. Todavia, tem havido esforços de ressignificação, transformando-o em um conceito analítico. Os sentidos da prática, por sua vez, tendem a ser mais simples, interpretando o eixo geralmente como uma linha ou uma porção do espaço a ligar duas localidades. Após essa reconstituição, procedemos regressivamente com uma análise, procurando encontrar as condições objetivas que possibilitaram a gênese do conceito de eixo e de corredor, o qual referencia, em geral, a mesma espacialidade. Essas gêneses podem ser identificadas na conceituação e na teorização sobre eixo, desenvolvida por Pierre Pottier em 1963, e na de corredor, feita por Charles F. J. Whebell em 1969. Finalmente, retornamos progressivamente ao presente, iluminando-o com base na compreensão mais ampla do devir conceitual de eixo ocasionada pelo conjunto das investigações. Nesse sentido, confirmamos nossa tese, enunciada a seguir: O conceito de eixo, em seu sentido de espacialidade social ― o qual não deve ser desvinculado do conceito de corredor ―, encontra sua gênese na década de 1960 como conceito analítico voltado para compreender determinadas expressões espaciais do desenvolvimento econômico. Seu devir, porém, é marcado por sua significativa instrumentalização pelo planejamento territorial neoliberal, notadamente a partir dos anos 1990, distorcendo os sentidos originais. A difusão dos sentidos normativos desde então tem influência predominante sobre as definições científicas e do senso comum, embora esforços recentes no campo analítico tenham procurado ressignificar o conceito de eixo, dando-lhe maior embasamento teórico, algo que a recuperação das formulações originais pode ajudar. / [en] The main objective of this thesis is to critically understand the conceptual history of axis as it refers to a social spatiality, elucidating its genesis and its becoming through the investigation of the trajectories of its main meanings and functions. Axis as a concept is increasingly relevant to geography and other sciences concerned with social space since it enables a more precise understanding of the relationship between space and circulation. Our research problem is: What are the genesis of the concept of axis and the fundamentals of its historical becoming and what does this becoming point to in terms of possibilities not fully realised. To solve it, we adopt an interlacement between the methods of conceptual history as developed by Reinhart Koselleck and an approach based on the regressive-progressive method applied by Karl Marx and clarified by Henri Lefebvre and Jean-Paul Sartre. Based on such interlacement, our research begins with a reconstitution of the recent uses and meanings of axis, supported by the idea that concepts can present analytical, normative, and practical senses. First, we observe how territorial planning instrumentalises the concept of axis based on the imperative of neoliberalisation and of fluidity. Then we examine the influence that the normative concept of axis has over the scientific field, noticing critical and acritical reproductions of such meanings. However, there have been efforts of resignification, transforming it into an analytical concept. The practical meanings, in their turn, tend to be simpler, usually interpreting the axis as a line or a portion of space linking two localities. After this reconstitution, we proceed with a regressive analysis, searching for the objective conditions that have enabled the genesis of axis and corridor as concepts, both generally referring to the same spatiality. These geneses can be spotted on the conceptualisation and the theorisation of axis developed by Pierre Pottier in 1963, and of corridor by Charles F. J. Whebell in 1969. Finally, we progressively return to the present time, clarifying it with the help from a broader understanding of the conceptual becoming of axis made possible by the research done. Therefore we confirm our thesis as it follows: The concept of axis, in its sense of a social spatiality ―which shall not be unlinked from the concept of corridor―, finds its genesis in the 1960s as an analytical concept dedicated to understand certain spatial expressions of economic development. Its becoming, however, is marked by its significant instrumentalization done by the neoliberal territorial planning, especially from the 1990s onwards, which distorts its original meanings. Since then, the diffusion of the normative meanings has a prevailing influence over the scientific definitions and those of the common sense. Despite that, recent efforts within the analytical field are trying to reframe the concept of axis, strengthening its theoretical basis, something that the recovery of the original senses may assist.
23

The social and economic effects of the Rea Vaya Bus Rapid Transit System (BRT) in the Gauteng Province

Rahim, Haseena 01 1900 (has links)
This study aimed at examining the social and economic effects of the Rea Vaya Bus Rapid Transit system (BRT) on various stakeholders in Johannesburg. The objective of the study was to investigate the effect the Rea Vaya has had on users and non-users of the Rea Vaya system. The findings of this study suggest that the Rea Vaya is beneficial in that it provides an option in modes of transport for commuters, particularly for people who were historically disadvantaged and were not permitted to reside in the city during the apartheid era. BRT systems are designed to provide a safe, reliable and accessible public transport system. The Rea Vaya system is aimed at providing better public transport, reducing congestion, on public roads, improving the roads and creating jobs. The findings have shown that the Rea Vaya has not been successful in meeting all its aims. The Rea Vaya has not managed to provide an accessible transport system thus far. Traffic in the inner city has not been reduced as a modal shift has not yet occurred. Since the inception of the Rea Vaya system there has been resistance from the Taxi Industry. Despite negotiations and attempts made by the Municipality of the City of Johannesburg to include the Taxi Industry in the Rea Vaya system, by making them shareholders of the system, the findings presented affirms that there is still resentment and resistance from the Taxi Industry towards the Rea Vaya system. The loss of revenue since the introduction of the Rea Vaya has caused a challenge for Taxi owners. Not only is it alleged that the Rea Vaya has affected the Taxi Industry, but the Rea Vaya infrastructure has caused a number of problems for private car users in the City. Private car users are inconvenienced by the designated bus lanes and lack of road signage in the city. These conclusions affirm that the Rea Vaya is not beneficial to all stakeholders in the City of Johannesburg. The experiences and opinions of users and non-users suggest that the system has a number of deficiencies. However some users of the system have benefited socially and economically. For some of the users the Rea Vaya has created a few opportunities; however the poor customer service from bus drivers and station staff was seen as a setback. Transit Orientated development in Johannesburg has not yet taken off. The government’s attempts to create mixed land use through the implementation of corridors of freedom are in its infant stages. Businesses across the Rea Vaya station found the Rea Vaya to have both positive and negative effects on their businesses. Some businesses found that the development of stations have added aesthetic value, however due to the frequency of Rea Vaya buses at stations, commuters would not wait for long periods of time and this resulted in fewer customers for businesses across the Rea Vaya station. The Rea Vaya system has provided a safe and reliable transport system in Johannesburg. However, the system is in its infant stages and has a number of deficiencies as presented in the findings of this study. / Geography / M. Sc. (Geography)
24

The social and economic effects of the Rea Vaya Bus Rapid Transit System (BRT) in the Gauteng Province

Rahim, Haseena 01 1900 (has links)
This study aimed at examining the social and economic effects of the Rea Vaya Bus Rapid Transit system (BRT) on various stakeholders in Johannesburg. The objective of the study was to investigate the effect the Rea Vaya has had on users and non-users of the Rea Vaya system. The findings of this study suggest that the Rea Vaya is beneficial in that it provides an option in modes of transport for commuters, particularly for people who were historically disadvantaged and were not permitted to reside in the city during the apartheid era. BRT systems are designed to provide a safe, reliable and accessible public transport system. The Rea Vaya system is aimed at providing better public transport, reducing congestion, on public roads, improving the roads and creating jobs. The findings have shown that the Rea Vaya has not been successful in meeting all its aims. The Rea Vaya has not managed to provide an accessible transport system thus far. Traffic in the inner city has not been reduced as a modal shift has not yet occurred. Since the inception of the Rea Vaya system there has been resistance from the Taxi Industry. Despite negotiations and attempts made by the Municipality of the City of Johannesburg to include the Taxi Industry in the Rea Vaya system, by making them shareholders of the system, the findings presented affirms that there is still resentment and resistance from the Taxi Industry towards the Rea Vaya system. The loss of revenue since the introduction of the Rea Vaya has caused a challenge for Taxi owners. Not only is it alleged that the Rea Vaya has affected the Taxi Industry, but the Rea Vaya infrastructure has caused a number of problems for private car users in the City. Private car users are inconvenienced by the designated bus lanes and lack of road signage in the city. These conclusions affirm that the Rea Vaya is not beneficial to all stakeholders in the City of Johannesburg. The experiences and opinions of users and non-users suggest that the system has a number of deficiencies. However some users of the system have benefited socially and economically. For some of the users the Rea Vaya has created a few opportunities; however the poor customer service from bus drivers and station staff was seen as a setback. Transit Orientated development in Johannesburg has not yet taken off. The government’s attempts to create mixed land use through the implementation of corridors of freedom are in its infant stages. Businesses across the Rea Vaya station found the Rea Vaya to have both positive and negative effects on their businesses. Some businesses found that the development of stations have added aesthetic value, however due to the frequency of Rea Vaya buses at stations, commuters would not wait for long periods of time and this resulted in fewer customers for businesses across the Rea Vaya station. The Rea Vaya system has provided a safe and reliable transport system in Johannesburg. However, the system is in its infant stages and has a number of deficiencies as presented in the findings of this study. / Geography / M. Sc. (Geography)
25

Das E-Lastenrad als Alternative im städtischen Wirtschaftsverkehr. Determinanten der Nutzung eines „neuen alten“ Fahrzeugkonzepts

Gruber, Johannes 05 March 2021 (has links)
Elektrifizierte Lastenfahrräder werden als ein Lösungsansatz für die wachsenden Herausforderungen des städtischen Wirtschaftsverkehrs gesehen. Fokus dieser Arbeit ist eine Abschätzung des Einsatzpotenzials dieses Fahrzeugkonzepts unter Betrachtung von konzeptionellen, verkehrlichen und wirtschaftlichen Aspekten. Als kumulative Dissertation enthält sie fünf Fachartikel, gruppiert zu drei Forschungsbeiträgen. Im ersten Forschungsbeitrag wird erörtert, wie erfolgversprechend das E-Lastenrad, eine Neuauflage des alten Konzepts Lastenfahrrad, in einem Markt mit ersten Anwendern (Kurierdienstleistung) ist. Die Auftragsstruktur im Stadtkuriergeschäft bietet ein substanzielles Marktpotenzial für E-Lastenräder, allerdings erschwert die Positionierung zwischen zwei etablierten Modi (Pkw und Fahrrad) den Markteintritt. Der zweite Teil der Analyse weitet den Blick auf alle Branchen und bietet eine strukturierte Beschreibung der verschiedenartigen Einflussfaktoren (Treiber und Hemmnisse), die auf die Lastenradnutzung im städtischen Wirtschaftsverkehr wirken. Als relevante Entscheidungskriterien konnten identifiziert werden: fahrzeugseitige Aspekte, Strukturen und Prozesse des adoptierenden Unternehmens, Einstellungen der Entscheider*innen, weiche Faktoren sowie regulative und räumliche Rahmenbedingungen. Der dritte Beitrag thematisiert die operative Eignung des E-Lastenrads, indem seine Fahrtzeiten einem Pkw gegenübergestellt werden. Bei Strecken bis zu 3 km sind beide Modi nahezu gleich schnell. Die Hälfte aller Fahrten bis 20 km Distanz würde bei einem Wechsel vom Pkw zum Lastenrad höchstens 2–10 min länger dauern (ohne Berücksichtigung der Parksuchzeit). Bereits kleine Änderungen an den Verkehrsbedingungen könnten noch bestehende Vorteile des Pkw spürbar verringern. Insgesamt erweitert die Arbeit maßgeblich das Wissen zu einem „neuen alten“ Fahrzeugkonzept, dem ein Potenzial zur Auflösung von bislang auf das Automobil hin ausgerichteten Systemen beigemessen wird. / Shifting trips to electric cargo bikes is one possible solution to deal with the growing challenges of urban commercial transport. This thesis combines conceptual, transport-related, and economic aspects as a foundation to assess the feasibility of this vehicle concept for freight and service trips. It contains five scientific papers, which provide three research contributions. The first contribution identifies the potentials of electric cargo bikes among first users (i.e., courier logistics services). Electric cargo bikes are an updated and re-envisioned version of freight bicycles. The features of point-to-point courier logistics assignments offer a substantial market opportunity for electric cargo bikes. However, being positioned between two established modes (i.e., car and bicycle) handicaps the market entry of cargo bikes. For the second contribution, the scope was widened to include all business sectors. A structured description is presented of the various determinants (i.e., drivers and barriers) affecting commercial cargo bike use. Among these were vehicle-specific factors, structures and practices of the company, attitudes of decision-makers, soft factors, regulatory frameworks, and spatial conditions. The third contribution explores the travel time differences between electric cargo bikes and cars for commercial trips. For trip distances of up to 3 kilometers, the travel times of both modes largely overlap. Half of all trips up to 20 kilometers would take only a maximum of 2 to 10 minutes longer by electric cargo bike (excluding the additional time for finding a parking spot). Small modifications in traffic could have considerable effects in reducing the current travel time advantages of cars. Consequently, this dissertation contributes towards the state-of-research by expanding the scientific knowledge of a type of vehicle that has the potential to disrupt car-dependent transportation systems.

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