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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.
121

Caractérisation de l'anglais comme lingua franca professionnelle à travers une analyse de corpus de courriels échangés en entreprise : une étude de registre / Characterisation of English as a professional lingua franca : a corpus-based, register study of corporate emails

Millot, Philippe 15 November 2012 (has links)
Cette thèse est une contribution à la branche professionnelle de l'anglais de spécialité et au domaine de l'anglais comme lingua franca. Le contexte de la recherche est le milieu de l'entreprise où les employés échangent des courriels dans le cadre de la réalisation d'actions professionnelles routinières. Dans ce contexte, l'anglais est considéré comme une langue internationale et, dans la situation où les employés sont natifs d'autres langues que l'anglais, la lingua franca. La première partie traite des quatre concepts fondamentaux de cette recherche : l'anglais comme langue internationale, le registre, la phraséologie et les discours professionnels. De ces quatre concepts émerge l'hypothèse selon laquelle l'analyse du discours professionnel en général et des courriels professionnels en particulier reposent sur la modélisation de situations professionnelles récurrentes en situations professionnelles typiques d'échange. Cette modélisation permet ensuite une analyse de registre. La seconde partie présente la démarche méthodologique dont l'objectif estla constitution d'un corpus de 500 courriels professionnels à partir d'une base de données plus large que nous avons constituée lors de notre enquête de terrain dans le monde de l'entreprise. Le corpus est tout d'abord défini selon quatre situations linguistiques que nous présentons ci-dessous : 1. scripteurs natifs et destinataires natifs 2. scripteurs natifs et destinataires non natifs 3. scripteurs non natifs et destinataires natifs 4. scripteurs non natifs et destinataires non natifs Il est ensuite défini selon les quatre situations professionnelles suivantes : 1. achats et ventes de produits 2. management d'équipes distantes 3. administration des ressources humaines 4. résolution de problèmes techniques A partir de ce corpus, nous menons une étude de la variation sur trois ensembles de traits linguistico-discursifs et paralinguistiques qui nous permettent d'évaluer le degré de minimalisme dans les courriels, le degré d'imbrication du texte dans le contexte ainsi que de mesurer le caractère interpersonnel et intime de ce type d'échange. Notre étude nous mène tout d'abord à confirmer que l'analyse de registre est une approche efficace pour la caractérisation des discours ordinaires et routiniers dans les entreprises. Elle interroge ensuite la solidité des normes et du concept de communauté de discours en présentant l'anglais en circulation sur les réseaux professionnels, éphémères et mondiaux, comme une variété fluide. / This dissertation is a contribution to both the professional branch of English for Specific Purposes and English as a lingua franca. The research takes place in the corporate world where employees exchange emails during the course of their professional routines. In this context, English is considered as an international language and, in the situations where employees are natives of other languages than English, the lingua franca. In the first part, the four fundamental concepts used in this study are introduced: (1) English as an international language, (2) register, (3) phraseology, and (4) professional discourse. From this introduction emerges the hypothesis that professional discourse analysis in general and professional emails in particular are based on modelising recurrent, professional situations into typical exchange situations then allowing for register analysis. The second part deals with the methodological approach which consists in building a corpus comprising 500 messages extracted from a larger database which was collected while we did fieldwork in the corporate world. The corpus is defined by the four following linguistic situations : 1. native professionals writing to native professionals 2. native professionals writing to non-native professionals 3. non-native professionals writing to native professionals 4. non-native professionals writing to non-native professionals It is also defined by four professional situations, namely : 1. selling and purchasing 2. team management 3. human resources management 4. technical problem solving The situations are then used to conduct a corpus-based, register analysis alongthree linguistic and paralinguistic dimensions. Each dimension seeks to characterise professional emails as a form of minimal, embedded, and interpersonal discourse. More generally, this thesis explores and challenges the solidity of traditional norms and that of the concept of discourse community by presenting the English used in global, ephemeral and professional networks as a fluid variety.
122

Sparse graph codes on a multi-dimensional WCDMA platform

Vlok, Jacobus David 04 July 2007 (has links)
Digital technology has made complex signal processing possible in communication systems and greatly improved the performance and quality of most modern telecommunication systems. The telecommunication industry and specifically mobile wireless telephone and computer networks have shown phenomenal growth in both the number of subscribers and emerging services, resulting in rapid consumption of common resources of which the electromagnetic spectrum is the most important. Technological advances and research in digital communication are necessary to satisfy the growing demand, to fuel the demand and to exploit all the possibilities and business opportunities. Efficient management and distribution of resources facilitated by state-of-the-art algorithms are indispensable in modern communication networks. The challenge in communication system design is to construct a system that can accurately reproduce the transmitted source message at the receiver. The channel connecting the transmitter and receiver introduces detrimental effects and limits the reliability and speed of information transfer between the source and destination. Typical channel effects encountered in mobile wireless communication systems include path loss between the transmitter and receiver, noise caused by the environment and electronics in the system, and fading caused by multiple paths and movement in the communication channel. In multiple access systems, different users cause interference in each other’s signals and adversely affect the system performance. To ensure reliable communication, methods to overcome channel effects must be devised and implemented in the system. Techniques used to improve system performance and capacity include temporal, frequency, polarisation and spatial diversity. This dissertation is concerned mainly with temporal or time diversity. Channel coding is a temporal diversity scheme and aims to improve the system error performance by adding structured redundancy to the transmitted message. The receiver exploits the redundancy to infer with greater accuracy which message was transmitted, compared with uncoded systems. Sparse graph codes are channel codes represented as sparse probabilistic graphical models which originated in artificial intelligence theory. These channel codes are described as factor graph structures with bit nodes, representing the transmitted codeword bits, and bit-constrained or check nodes. Each constraint involves only a small number of code bits, resulting in a sparse factor graph with far fewer connections between bit and check nodes than the maximum number of possible connections. Sparse graph codes are iteratively decoded using message passing or belief propagation algorithms. Three classes of iteratively decodable channel codes are considered in this study, including low-density parity-check (LDPC), Turbo and repeat-accumulate (RA) codes. The modulation platform presented in this dissertation is a spectrally efficient wideband system employing orthogonal complex spreading sequences (CSSs) to spread information sequences over a wider frequency band in multiple modulation dimensions. Special features of these spreading sequences include their constant envelopes and power output, providing communication range or device battery life advantages. This study shows that multiple layer modulation (MLM) can be used to transmit parallel data streams with improved spectral efficiency compared with single-layer modulation, providing data throughput rates proportional to the number of modulation layers at performances equivalent to single-layer modulation. Alternatively, multiple modulation layers can be used to transmit coded information to achieve improved error performance at throughput rates equivalent to a single layer system / Dissertation (MEng (Electronic Engineering))--University of Pretoria, 2007. / Electrical, Electronic and Computer Engineering / unrestricted
123

Výzkum faktorů ovlivňujících výkonnost podniků / Analysis of Business Performance Factors

Janková, Ivana January 2011 (has links)
This graduation theses analyses intercompany comparisons using one-dimensional and multi-dimensional methods. It focuses on enterprises actuating in terms of a subsegment of national economy – building industry. Factors that influence the performance of companies most in this field will be selected by using correlation coefficient. Its economic development during the years and also characteristics of the industry will be described in details.
124

Identifikace faktorů výkonnosti podniku působícího v oboru ICT / Identification of Performance Factors of the Company in the Field ICT

Drábková, Pavlína January 2012 (has links)
The diploma thesis focuses on finding and identification of performance factors of the company by means of intercompany comparisons methods. It analyzes the company which operates in the field of information and communication technologies and is compared with companies in related field of national economy. The performance factors of the company are selected by means of correlation analysis, which influences the performance of the company, afterwards there are compared the positions selected of companies by means of intercompany comparison methods in particular years.
125

Visipedia - Multi-dimensional Object Embedding Based on Perceptual Similarity / Visipedia - Multi-Dimensional Object Embedding Based on Perceptual Similarity

Matera, Tomáš January 2014 (has links)
Problémy jako je jemnozrnná kategorizace či výpočty s využitím lidských zdrojů se v posledních letech v komunitě stávají stále populárnějšími, což dosvědčuje i značné množství publikací na tato témata. Zatímco většina těchto prací využívá "klasických'' obrazových příznaků extrahovaných počítačem, tato se zaměřuje především na percepční vlastnosti, které nemohou být snadno zachyceny počítači a vyžadují zapojení lidí do procesu sběru dat. Práce zkoumá možnosti levného a efektivního získávání percepčních podobností od uživatelů rovněž ve vztahu ke škálovatelnosti. Dále vyhodnocuje několik relevantních experimentů a představuje metody zlepšující efektivitu sběru dat. Jsou zde také shrnuty a porovnány metody učení multidimenzionálního indexování a prohledávání tohoto prostoru. Získané výsledky jsou následně užity v komplexním experimentu vyhodnoceném na datasetu obrázků jídel. Procedura začíná získáváním podobností od uživatelů, pokračuje vytvořením multidimenzionálního prostoru jídel a končí prohledáváním tohoto prostoru.
126

Covariation estimation for multi-dimensional Lévy processes based on high-frequency observations

Papagiannouli, Aikaterini 07 March 2023 (has links)
Gegenstand dieser Dissertation ist die non-parametrische Schätzung der Kovarianz in multi-dimensionalen Lévy-Prozessen auf der Basis von Hochfrequenzbeobachtungen. Im ersten Teil der Arbeit wird eine modifizierte Version der von Jacod und Reiß vorgeschlagenen Methode der Hochfrequenzbeobachtung für die Ermittlung der Kovarianz multi-dimensionaler Lévy-Prozesse gegeben. Es wird gezeigt, dass der Kovarianzschätzer optimal im Minimaxsinn ist. Darüber hinaus demonstrieren wir, dass die Indexaktivität der co-jumps durch das harmonische Mittel der Sprungaktivitätsinzidenzen der Komponenten von unten beschränkt wird. Der zweite Teil behandelt das Problem der adaptiven Schätzung. Ausgehend von einer Familie asymptotischer Minimax-Schätzer der Kovarianz, erhalten wir einen datenbasierten Schätzer. Wir wenden Lepskii’s Methode an, um die Kovarianz an die unbekannte Aktivität des co-jumps Indexes des Sprungteils anzupassen. Da wir es mit einem Adaptierungsproblem zu tun haben, müssen wir eine Schätzung der charakteristischen Funktion des multi-dimensionalen Lévy-Prozesses konstruieren, damit die charakteristische Funktion weder von einer semiparametrischen Annahme abhängt noch schnell abfällt. Aus diesem Grund wird auf Basis von Neumanns Methode ein trunkierter Schätzer für die empirische charakteristische Funktion konstruiert. Die Anwesenheit der trunkierten, empirischen charakteristischen Funktion im Zähler führt jedoch zu einer Situation, die auch bei der Deconvolution auftritt, d.h. einem irregulären Verhalten des stochastischen Fehlers. Dieser U-förmige stochastische Fehler verhindert die Anwendung von Lepskii’s Grundsatz. Um diesem Problem, entgegenzuwirken, entwickeln wir eine Strategie, welche zu einem Orakelstart von Lepskii's Methode führt, mit deren Hilfe ein monoton steigender stochastischer Fehler konstruiert wird. Dies erlaubt uns, ein Balancing Principle einzuführen und einen adaptiven Schätzer für die Kovarianz zu erhalten, der fast-optimale Raten erzeugt. / In this thesis, we consider the problem of nonparametric estimation for the continuous part of the covariation of a multi-dimensional Lévy process from high-frequency observations. This continuous part of covariation is also called covariance. The first part modifies the high-frequency estimation method, proposed by Jacod and Reiss, to cover estimation of the covariance of multi-dimensional Lévy processes. The covariance estimator is shown to be optimal in the minimax-sense. Moreover, the co-jump index activity is proved to be bounded from below by the harmonic mean of the jump activity indices of the components. In the second part, we address the problem of the adaptive estimation. Starting from an asymptotically minimax family of estimators for the covariance, we derive a data-driven estimator. Lepskii's method is applied to adapt the covariance to the unknown co-jump index activity of the jump part. Faced with an adaptation problem, we need to secure an estimation for the characteristic function of the multi-dimensional Lévy process so that it does not depend on a semiparametric assumption and, at the same time, does not decay fast. For this reason, a truncated estimator for the empirical characteristic function is constructed based on Neumann's method. The presence of the truncated empirical characteristic function in the denominator leads to a situation similar to the deconvolution problem, i.e., an irregular behavior of the stochastic error. This U-shaped stochastic error does not permit us to apply Lepskii's principle. To counteract this problem, we establish a strategy to obtain an oracle start of Lepskii's method, according to which a monotonically increasing stochastic error is constructed. This enables us to apply a balancing principle and build an adaptive estimator for the covariance which obtains near-optimal rates.
127

Novel tools for ultrafast spectroscopy

Jarvis, Thomas William 06 February 2012 (has links)
Exciton dynamics in semiconductor nanostructures are dominated by the effects of many-body physics. The application of coherent spectroscopic tools, such as two-dimensional Fourier transform spectroscopy (2dFTS), to the study of these systems can reveal signatures of these effects, and in combination with sophisticated theoretical modeling, can lead to more complete understanding of the behaviour of these systems. 2dFTS has previously been applied to the study of GaAs quantum well samples. In this thesis, we outline a precis of the technique before describing our own experiments using 2dFTS in a partially collinear geometry. This geometry has previously been used to study chemical systems, but we believe these experiments to be the first such performed on semiconductor samples. We extend this technique to a reflection mode 2dFTS experiment, which we believe to be the first such measurement. In order to extend the techniques of coherent spectroscopy to structured systems, we construct an experimental apparatus that permits us to control the beam geometry used to perform four-wave mixing reflection measurements. To isolate extremely weak signals from intense background fields, we extend a conventional lock-in detection scheme to one that treats the optical fields exciting the sample on an unequal footing. To the best of our knowledge, these measurements represent a novel spectroscopic tool that has not previously been described. / text
128

Houding teenoor televisie-advertensie : 'n psigometriese perspektief / Attitude towards television commercials : a psychometric perspective

Joubert, Johan Pierre Retief 06 1900 (has links)
Text in Afrikaans / Dit is belangrik vir bemarkingsorganisasies om die effek van bemarkingsaksies en meer spesifiek reklame te meet van wee eskalerende koste-oorwegings. Wat die rol van reklame in verbruikersgedrag betref, is die belewing van of houding-teenoor-reklame konsepte van sentrale be lang. Aangesien die term bel ewing meer beskrywend is oor die impak wat advertensies op verbruikers het word hierdie term algemeen gebruik. Hierdie studie ondersoek die konsep advertensiewaardering en ontleed die invloed daarvan op advertensiebelewing. Die kyker-responsprofiel soos deur Schlinger (1979) ontwikkel, word algemeen gebruik om televisiekykers se houding teenoor televisie-advertensies te meet. Hierdie studie poog om die toepaslikheid en geldigheid van die kyker-responsprofiel onder Suid-Afrikaanse televisiekykers te ondersoek. Die navorsingsmetode het uit twee fases bestaan. Die eerste fase was meer kwalitatief van aard, en ondersoek kykers se kognitiewe struktuur van houding teenoor televisie-advertensies. Die teoretiese uitgangspunt tydens hierdie fase is persoonlike-konstrukteorie. Repertoriumrooster onderhoude is met 50 volwasse televisiekykers (ouer as 16 jaar) uit verskillende taalgroepe gevoer. Daar is bevind dat kykers gemiddeld ses konstrukte gebruik ten einde die waarderingsvlak van advertensies te bepaal. 313 Konstrukte is in totaal deur die 50 respondente ontlok. Hierdie konstruke is deur individuele roosterontledings en ooreenkomsanalise tot 'n aantal konstrukgroepe gereduseer. Beskrywings van konstrukgroepe is aan die hand van n literatuurnavorsing gedoen. Die konstrukgroepe (tevredenheid, vermaaklikheid, interessantheid, sosialiteit, duidelikheid, realiteit, tempo en emosialiteit) toon 'n mate van ooreenstemming met die sewe Schlinger basisfaktore. Die onderliggende indiwiduele konstrukte wat vermaaklikheid, sosialiteit tempo en interessantheid beskryf, toon hoe korrelasies met waardering wat daarop dui dat waardering meer as net vermaaklikheid behels. Fase twee was meer kwantitatief van aard en het die ontleding van 382 kykerresponsprofiele behels. 'n Faktorontleding van die 32 Schlinger-items het sewe basisfaktore tot gevolg. Die eerste vyf faktore (vermaaklikheid, verwarring, relevante nuus, handelsmerkversterking en empatie) beskik oor soortgelyke faktorladings as faktorontledings wat in die V.S.A. gedoen is. Hierdie bevinding dui daarop dat die affektiewe belewingstruktuur van televisiekykers in Suid-Afrika grootliks dieselfde is as kykers in die Verenigde State. Die ander twee faktore (familiariteit en vervreemding) se ladings verskil van die in die Verenigde State maar hierdie verskille kan gegewe die aard van die advertensies ( bestaande en nuwe advertensiekonsepte) en die kruiskulturele aard van Suid-Afrikaanse kykers verklaar word. Die Schlingeritems is statisties beskryf en ontleed deur die rol wat die tipe advertensie (bestaande versus nuwe), produk-kategorie en kulturele teikenmark speel in waardering van advertensies te ondersoeK. Nuwe konsepte is geneig om meer vermaaklik en relevant te wees. Zulu, Sotho en Xhose kykers is geneig om advertensies as meer positief te beleef. Kosmetika en medisinale-, korporatiewe- en motoradvertensies is verder minder vermaaklik as voedsel en handelsadvertensies. Die Schlingeritems wat advertensiewaardering die beste beskryf en voorspel is bepaal deur bondelontledings en meerdimensionele verskaling. Daar is gevind dat waardering die mate waartoe 'n advertensie aan die vermaaklikheids, empatie en relevante nuus doelwitte voldoen sonder om verwarrend, vervreemdend of oorbekend te wees. Dit wil voorkom of daar twee dimensies bestaan wat die meeste variansie in Schlingeritems verklaar naamlik waardering (positief of negatief) en relevansie. Bondelontleding dui verder daarop dat 'n positiewe persepsie van 'n geadverteerde handelsmerk kykers ontvanklik maak om meer van 'n advertensie te hou of te waardeer. / It is important that, given escalating cost considerations, marketing organisations determine the effect that their marketing efforts have. With regard to the role of advertising m consumer behaviour, attitude towards commercials is of utmost importance. This study examined the liking of television advertisement concept and analyses the effect of this concept on attitude towards television advertising. The viewer response profile as developed by Schlinger (1979) is commonly used to evaluate viewer's attitude towards television commercials. This study attempted to investigate the applicability and validity of this instrument amongst South African television viewers. The study consisted of two phases. Phase one was more qualitative in nature and investigated the viewer's cognitive structure of attitude towards television commercials. The theoretical approach used during this phase was personal construct theory. It was found that viewers on average use six constructs to evaluate whether they like or dislike commercials. 313 Constructs were elicited and based on individual grid analyses and correspondence analysis a reduced number of construct groups was identified. These construct groups ( contentness, entertainment, interesting, sociality, clearness, reality, emotionality, and tempo) show a measure of similarity to the seven Schlinger factors or dimensions. The individual constructs, which make up entertainment, sociality, emotionality, tempo and interesting, show high levels of correlation with advertisement liking. This finding suggests that advertisement liking involve more than pure entertainment. Phase two was more quantitative and consisted of analysing 382 viewer response profiles. A factor analysis of the 32 items, which make up the viewer response profile, resulted in seven factors. The first five factors (entertainment, confusion, relevant news, brand reinforcement and empathy) show similar factor loading to factor analytical studies done in the United State of America. The other two factors (familiarity and alienation) show different loading to the United States of America study but these differences could be explained given the nature of commercials tested (existing commercials and new commercial concepts) and the cross cultural nature of South African viewers. The Schlinger items were analysed in greater detail by investigating the role which type of commercial (existing versus new), product category and cultural target market play in liking of commercials. New concepts are proven to be more entertaining, creative and relevant. Zulu and Sotho viewers are likely to be more positively disposed towards television commercials while cosmetic, medicine, corporate and motor vehicle commercials are less entertaining than food and commercial commercials. Those Schlinger items, which best describe and predict commercials liking were determined by using cluster and multi dimensional scaling techniques. It is apparent from this analysis that likability is the extent to which the objective of entertainment, empathy or relevant news is achieved without confusion, alienation or familiarity. Cluster analysis furthermore suggests that a positive perception of an advertised brand predispose viewers to higher levels of commercial liking. Multi dimensional scaling suggest two dimensions explaining most of the Schlinger factor variance namely liking (positive of negative) and relevance. / Industrial and Organisational Psychology / D. Com. (Bedryfsielkunde)
129

Sub-optimal Energy Management Architecture for Intelligent Hybrid Electric Bus : Deterministic vs. Stochastic DP strategy in Urban Conditions / Architecture de gestion de l'énergie sous-optimale pour les bus électriques hybrides intelligents : stratégie basée DP déterministe versus stratégie basée DP stochastique en milieu urbain

Abdrakhmanov, Rustem 27 June 2019 (has links)
Cette thèse propose des stratégies de gestion de l'énergie conçues pour un bus urbain électrique hybride. Le système de commande hybride devrait créer une stratégie efficace de coordination du flux d’énergie entre le moteur thermique, la batterie, les moteurs électriques et hydrauliques. Tout d'abord, une approche basée sur la programmation dynamique déterministe (DDP) a été proposée : algorithme d'optimisation simultanée de la vitesse et de la puissance pour un trajet donné (limité par la distance parcourue et le temps de parcours). Cet algorithme s’avère être gourmand en temps de calcul, il n’a pas été donc possible de l’utiliser en temps réel. Pour remédier à cet inconvénient, une base de données de profils optimaux basée sur DP (OPD-DP) a été construite pour une application en temps réel. Ensuite, une technique de programmation dynamique stochastique (SDP) a été utilisée pour générer simultanément et d’une manière optimale un profil approprié de la vitesse du Bus ainsi que sa stratégie de partage de puissance correspondante. Cette approche prend en compte à la fois la nature stochastique du comportement de conduite et les conditions de circulations urbaines (soumises à de multiples aléas). Le problème d’optimisation énergétique formulé, en tant que problème intrinsèquement multi-objectif, a été transformé en plusieurs problèmes à objectif unique avec contraintes utilisant une méthode ε-constraint afin de déterminer un ensemble de solutions optimales (le front de Pareto).En milieu urbain, en raison des conditions de circulation, des feux de circulation, un bus rencontre fréquemment des situations Stop&Go. Cela se traduit par une consommation d'énergie accrue lors notamment des démarrages. En ce sens, une stratégie de régulation de vitesse adaptative adaptée avec Stop&Go (eACCwSG) apporte un avantage indéniable. L'algorithme lisse le profil de vitesse pendant les phases d'accélération et de freinage du Bus. Une autre caractéristique importante de cet algorithme est l’aspect sécurité, étant donné que l’ACCwSG permet de maintenir une distance de sécurité afin d’éviter les collisions et d’appliquer un freinage en douceur. Comme il a été mentionné précédemment, un freinage en douceur assure le confort des passagers. / This PhD thesis proposes Energy Management Strategies conceived for a hybrid electrical urban bus. The hybrid control system should create an efficient strategy of coordinating the flow of energy between the heat engine, battery, electrical and hydraulic motors. Firstly, a Deterministic Dynamic Programming (DDP) based approach has been proposed: simultaneous speed and powersplit optimization algorithm for a given trip (constrained by the traveled distance and time limit). This algorithm turned out to be highly time consuming so it cannot be used in real-time. To overcome this drawback, an Optimal Profiles Database based on DP (OPD-DP) has been constructed for real-time application. Afterwards, a Stochastic Dynamic Programming (SDP) technique is used to simultaneously generate an optimal speed profile and related powersplit strategy. This approach takes into account a stochastic nature of the driving behavior and urban conditions. The formulated energy optimization problem, being intrinsically multi-objective problem, has been transformed into several single-objective ones with constraints using an ε-constraint method to determine a set of optimal solutions (the Pareto Front).In urban environment, due to traffic conditions, traffic lights, a bus encounters frequent Stop&Go situations. This results in increased energy consumption during the starts. In this sense, a relevant Eco Adaptive Cruise Control with Stop&Go (eACCwSG) strategy brings the undeniable benefit. The algorithm smooths speed profile during acceleration and braking phases. One more important feature of this algorithm is the safety aspect, as eACCwSG permits to maintain a safety distance in order to avoid collision and apply a smooth braking. As it was mentioned before, smooth braking ensures passengers comfort.
130

The (re)positioning of the Spanish metropolitan system within the European urban system (1986-2006)

Burns, Malcolm C. 18 July 2008 (has links)
The thesis seeks to demonstrate that during the period between 1986 and 2006, some of the principal cities of the Spanish metropolitan system1, have undergone significant change in terms of their European competitiveness. It is suggested that in the case of Madrid and Barcelona in particular this change has been of such a magnitude to proportion them a much more important place within the European spatial configuration than that which they occupied in the mid-1980s. Empirical evidence is offered to support this conjecture. The thesis lies wholly within the framework of spatial planning at the European territorial scale.It charts the comparative ascent of the Spanish cities from the moment of Spain's entry into the European Union (EU) in 1986 against the background of the development of European spatial policy, increased economic integration across Europe, the increased importance of the 'territorial' dimension of EU cohesion policy and an eventual waning of the applicability of the terminology of 'core' and 'periphery' to describe European geographical location.Part One (Chapter 1) addresses the processes of urbanisation in general from a global perspective and then focuses on metropolitan growth in a number of different historical contexts from the start of the 19th Century. Parts Two (Chapters 2-5) and Three (Chapters 6-9) of the thesis carry out analyses at two contrasting but complementary spatial scales. Part Two examines the metropolitan growth processes in Spain, in the period since 1857, detecting the historical moments in which there were surges in the metropolitan populations of the seven cities of the metropolitan system. The dimensions of the spatial units of analysis corresponding to the seven Spanish metropolitan urban regions are described, based upon a methodology first developed by the Universitat Politècnica de Catalunya (UPC) in the context of a transnational spatial planning project of the INTERREG community initiative2. These seven spatial units form the basis for a socio-economic analysis of the structure of the metropolitan system, drawing upon data principally from the 2001 Census. If by 1930 one of the key characteristics of Spain's urban system was having not just one but two cities (Madrid and Barcelona) belonging to the group of 27 cities across the world with populations in excess of 1 million inhabitants3, this same differentiation between the country's two largest cities and the remainder of the urban system is equally valid today. Spain's urban system remains clearly bicephalous in being dominated by these same two cities in terms of demographic and economic strength.Part Three begins by examining the evolution of European spatial policy against the background of an ever-enlarging European Union and changes with regard to the notion of cohesion - from a concept understood in terms of economic and social factors, to one in which the territorial dimension has become increasingly important. The European urban system is then critically examined through a number of key and influential studies, with particular regard to the rankings and hierarchies of metropolitan urban regions deriving there from and the changes in the placing of the Spanish metropolitan urban regions therein.Taking inspiration from the seminal contribution of Manuel Castells4 in the context of the structural changes resulting from the informational and technological revolution, the thesis seeks to replicate the concept of a 'space of flows'. This is carried out through a 'network analysis' approach drawing upon air passenger flows between some 28 European metropolitan urban regions of the EU15+2 group of countries, enabling the analysis of the interaction between these 28 cities. This methodology enables arriving at a number of descriptive indicators which in turn, through the application of a multi-dimensional scaling mathematical technique, permits comparing the functional and physical distances of each of the metropolitan urban regions from the centre of the 'conceptual space of air passenger flows' and the centre of gravity. The resulting map of the functional positioning of the cities offers a spatial vision of metropolitan Europe quite different to that based upon Cartesian coordinates. Such an approach enables demonstrating that cities such as Barcelona, Madrid, Helsinki, Lisbon and Athens, traditionally considered as physically peripheral to the European core area, appear to be more favourably positioned in functional terms. Furthermore in the case of Spain the results indicate that Barcelona lies closer to the centre of the conceptual 'space of air passenger flows' than Madrid.In light of this empirical evidence, together with the signs of increased economic integration across some parts of Spain, the prospects of Spain forming part of a wider European territorial concentration of flows and activities, and the recognition of the territorial capital of Madrid and Barcelona within recent EU spatial policy declarations, the thesis concludes in Part Four that these two metropolitan regions have undergone a clear consolidation and (re)positioning within the European metropolitan hierarchy.

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