Esta tesis doctoral se enmarca en el urbanismo, entendido como práctica social, y en específico, en el urbanismo ecológico. Está orientada a definir ámbitos de mediación como entornos de oportunidad de la ciudad que ligan identidades urbanas con el territorio y en los cuales es posible generar sentido de apropiación por parte de sus habitantes, y por tanto, a partir del capital social. transformar el metabolismo social hacia la sostenibilidad. Se parte de tres consideraciones fundamentales : Primero, que en la ciudad actual existe un modelo de ciclos abiertos caracterizado por la apropiación de recursos, uso y deposición al medio ambiente del material que ha perdido valor social en calidad degradada, lo cual genera contaminación y dificulta las posibilidades de mantener el potencial productivo de la matriz biofísica y dar soporte a la sociedad en el tiempo. Segundo, que existe una vinculación directa entre los esquemas de satisfactores para atender las necesidades de vida en la ciudad y el metabolismo social, y por tanto, este concepto resulta fundamental para abordar el problema de la ciudad. Tercero, el campo de observación se centra en las ciudades intermedias por los siguientes criterios: 1. Son objetivo clave para la sostenibilidad, dado que son los principales asentamientos humanos a nivel mundial; 2. Presentan cualidades de relación con el territorio que se expresan en la capacidad de formar redes de intercambio y reciprocidad con otros centros urbanos y áreas rurales y 3. Sus cualidades de relación con el territorio se reconocen como potencialidades para identificar ámbitos de mediación. Apartir de estas consideraciones se realiza la propuesta de ámbitos de mediación, concepto que se recoge de las ciencias sociales y se redefine en relación al metabolismo social para generar un instrumento de estudio e intervención de la ciudad - en particular de la ciudad intermedia - hacia la sostenibilidad, y que constituye la proposición principal de la tesis . El aporte en la redefinición del concepto de mediación consiste en vincular una serie de elementos conceptuales principales: el concepto de la mediación como espacio asociativo derivado de las ciencias sociales, los conceptos de apropiación y territorialización como procesos de identificación y simbolización del entorno y el concepto de metabolismo social. Una vez definidos los ámbitos de mediación se formulan unas bases para intervenciones urbanas , las cuales proporcionan una guía metodológica para abordar el estudio de la ciudad y que consiste en tres fases principales a saber 1. Diagnóstico físico - espacial y del metabolismo de la ciudad; 2. Reconocimiento de posibles ámbitos de mediación y 3. Caracterización y delimitación de los ámbitos de mediación. Se tiene como caso referencial la Estrategia Verde de Santiago de Compostela. España y como caso de estudio Mérida, Venezuela, ambas reconocidas en esta tesis como ciudades intermedias . La estrategia verde de Santiago proporciona una lectura sobre la ciudad y su relación con el territorio, así como lineamientos para reconocer espacios de mediación en la estructura organizativa de espacios verdes y sistema hídrico que plantea. El caso de estudio de la ciudad de Mérida, Venezuela permite evaluar el potencial de la propuesta de los ámbitos de mediación en la planificación de la ciudad, una planificación orientada a incrementar los valores ambientales y sociales de la ciudad y proyectarlos hacia el territorio. Tanto el caso referencial como el caso de estudio permiten reconocer en la propuesta de ámbitos de mediación un camino para la recuperación de la memoria social, herencia de unas reservas comunes , construidas, sostenidas y transmitidas por la comunidad y la cultura, así como de espacios de convivencia a través de los cuales restaurar la relación entre los procesos sociales y naturales de la ciudad hacia esquemas más sostenibles.

The general topic discussed in this dissertation is the question of limits as perceived and delimited by humans. More specifically it aims to investigate the concept of ecotones as it has emerged in the theory of landscape ecology and design, that is, as a zone of transition between two adjacent ecological systems of distinct characteristics; and accordingly it aims to transfer the ecotone concept to the anthropogenic urban environment and investigate its respective implications. In this manner an urban ecotone could be defined as the transition area between at least two adjacent distinct urban fabric / biomes / biotopes of differentiated characteristics (morphological, socio-economic, typological etc), where this ecotonal space is characterized by a pronounced edge effect, in terms of intensity and diversity and a set of defined spatial {length, shape) and time {rhythm, history) characteristics restricted to the ecotonal area but ultimately linked to the adjacent patches · internal dynamics. Due to these intrinsic characteristics it can be sustained that urban ecotones, if managed properly, they can play a key role in maintaining territorial integrity (ecological, functional) and in achieving resilience and long term sustainable yields. Similarly when thought out as reprogrammable urban /territorial interfaces, a direct simile to the membrane function found in organisms and ecosystems, urban ecotones can provide the base for a paradigm shift in our contemporary perspective on cities and their functioning. A shift from a confrontational and fragmented discourse towards a synergetic and cooperational model that highlights the latent complexity present in most urban regions and adapts a proactive stance towards the problematic socio-environmental crisis most contemporary cities face today. In this sense anthropogenic transformations of the territory are understood as a direct product of the social metabolism of each territory. This approach requires apart from a traditional morphological analysis an additional phenomenological approach where the interrelation and compatibilization of anthropogenic and natural activity and dynamics can only be achieved if the necessary conceptual and design tools are developed. For this purpose a case study was selected in order to apply and test the aformentioned concepts. Thus, the selection of the urban region of Thessaloniki corresponds to a series of selection criteria linked to its special characteristics as a coastal mediterranean city with a long and continuous historic course of respective succesion phases that have given rise to heterogeneous urban forms and situations. The thesis is structured in two volumes. The first one deals with all the theoretical and bibliographical research related to the topic in question as well as corresponding analysis results and conclusions. The second volume is thought out as an analysis atlas of the case-study of the urban region of Thessaloniki, following a multi-scalar perspective: On a first level it opts for a territorial / regional analys is on the limits of the administrative region of Central Macedonia, studying the wider regional mosaic structure and respectively identifying the distinct bioregions, diverse territorial situations, landscapes and ecotones encountered within the region. On a second level, the analysis focuses on the urban region of Thessaloniki, selecting six ecotones each one corresponding to respective city limits in distinct historic periods of the city's history and serving as key spatial indicators of past and present processes and dynamics. The timely coincidence of this research work with the Revision of the Regulatory Plan ofThessaloniki renders this research as relevant and useful in providing additional insights and alternatives on the table. On a more general level, the results produced are expected to be extrapolable and applicable to other cases of urban regions, whether within the mediterranean context or not.

The topic discussed in this dissertation is the study of the public spaces in Hong Kong. In recent decades the city has established itself as a major financial centre and production, aiming to be one of global cities of the new millennium. In particular the study focuses on the analysis of collective spaces present in the urban structure, i.e. those spaces that are neither proper public nor private, which represent a distinctive aspect of the city's form . In Hong Kong the use of public space assumes a peculiar character, functions that usually took place outdoors are moving in the interior spaces of malls, becoming one of the standard tools to attract people to the commercial spaces. In this sense one of the main problems affecting the development of the city is to control the process and the management of the public spaces, strengthening the relationship between public and private interest. Hong Kong is a city where the boundaries between public and private space fade, creating a new category of space. This introduces one of the main features that have generated the study of this research, that is to say, the lack of boundaries between public and private realm . The lack of boundaries, which does not necessarily means to the difference between open and closed spaces, but public spaces that are inside private properties, grey areas where it's difficult to understand which kind of spaces we are crossing. In fact, much of the urban structure, is used for commercial purposes, this aspect affects the use and the meaning of the public space that in general, are not sufficient to meet the expectations and needs of the population. In this regard the implementation of the open spaces in the city is one of the most recurrent topic of the Government of Hong Kong. Due to limited land resources (due to morphology only 24% of the territory is urbanized) the city has developed a vertical high density where the high cost of land has become a large business for the private sector. This study attempts to examine the main aspects of the privatization of public space, a phenomenon that in Asia is quite intense and, although less strongly, is involving the development of the European cities. During the eighties the Government of Hong Kong, in order to promote and improve the spatial quality versus high status density of the city, established the policy of POPS (Privately Owned Public Spaces) proceeding invented in New York, in 1960. The policy was created to promote the integration of public space in new developments by the private sector in exchange for bonus floor area. The property remains private, but the space is subject to the easement of public use in terms of access and use. In this case we have a space for public use that obviously is not a public domain, since it is not owned by the city. Despite his traditional role as main subject entitled to preserve the public space, the planning system in Hong Kong seems always weaker in front to the economic interest of the development of the city, losing the faculty to ensure the principals functions of the public life. The risk is that the responsibility and the management of the social life could transfer often more to private actors. This dissertation attempt to examine and evaluate this complex urban structure analysing the relationships that occur between the public spaces system, POPS and the other urban activities, through the identification of the main aspects that could improve the spatial structure of the city.

A través de la historia de la ciudad se vienen contemplando diferentes ideas, propuestas de solución al problema de la vivienda y su forma de ordenarla dentro del territorio urbano. En la actualidad una de las formas de presentarse estos modelos de urbanización son los fraccionamientos cerrados. Esta urbanización tiene como característica principal o singular el muro que delimita la zona de vivienda con el resto de la ciudad.El crecimiento en distintos países de la topología denominada en el presente trabajo como Ciudad Privatizada, llama a la reflexión sobre el tema y a conocer mas sobre el. Si bien, se establecen las características de estas topologías, se hecha en falta estudios que permitan conocer como afecta a los distintos sectores de la ciudad, así como los beneficios y obligaciones de las mismas.La Ciudad Privatizada, es una propuesta, cuyos inicios aparecen a principios del siglo XX, y evoluciona hasta llegar a los años 80 donde se presenta como la conocemos hasta hoy día. Actualmente se ha convertido en una alternativa importante para el desarrollador inmobiliario. Además, ha logrado tener una importante penetración en el urbanismo de países tan diversos como distintos.Este espacio privatizado se entiende como producto de la búsqueda de satisfacer la demanda del mercado actual, lo cual equivale a un mercado internacional, globalizado, que promueve la movilidad, el intercambio de capital humano de las diferentes compañías multinacionales y que conlleva la necesidad de satisfacer las necesidades básicas de la demanda y sus variables culturales, ideológicas y de formas de vida.Del incremento citado sobre la demanda de esta topología nace dar respuesta a una hipótesis: la privatización de espacios públicos genera un incremento del valor y precio de la propiedad.El objetivo principal del estudio es demostrar o aproximar, cuál es el valor que genera la ciudad privatizada al privatizar el espacio público.Para lograr el objetivo se utilizaron los Métodos de Precios Hedónicos y Valoración Contingente.

The focus of this study is the potential use of FTIR imaging as a tool for objective automated histopathology. The Thesis also reports the use of multivariate statistical techniques to analyse the FTIR imaging data. These include Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), Multivariate Curve Resolution (MCR) and Fuzzy C-Means Clustering (FCM). The development of a new PCA-FCM Clustering hybrid that can automatically detect the optimum clustering structure is also reported. Chapter 1 provides a brief introduction to the use of vibrational spectroscopy to characterise biomolecules in tissues and cells for medical diagnosis. Chapter 2 details the basic histology of a lymph node before proceeding to present imaging results gained from the analysis of both healthy and diseased lymph node tissue sections. The ability of each multivariate technique to discriminate different tissue types is discussed. In addition, the spectral features that are characteristic for each tissue type are reported. The development and application of a new PCA-FCM Clustering algorithm that can automatically determine the best clustering structure is also described in full. The results indicate that cellular abnormality provides changes to both the protein and nucleic acid vibrations. However, similar spectral profiles were identified for highly proliferating cells that were contained within reactive germinal centres of the lymph node. Chapter 3 provides a short introduction to the histology of the cervlx before presenting imaging results that were gained from the analysis of both healthy and diseased cervical tissue sections. The ability of each multivariate technique to discriminate different tissue types is discussed. In addition, the spectral features that are characteristic for each tissue type are described in detail. Novel imaging experiments upon exfoliated cervical cells are also presented. It would appear that cellular abnormality in cervical tissues and cells affects both the protein and nucleic acid features of the spectra. Glycogen and glycoprotein contributions that are prevalent in healthy tissues are also absent. Chapter 4 details sample preparation methods, the instrumentation and procedures used for data acquisition, and the subsequent data processing and multivariate techniques applied to analyse the collected spectral datasets.

Three leaves of erratum inserted inside front cover. / Bibliography: leaves 178-210. / x, 210 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The mature oophorectomised rat is a well-recognised model of post menopausal bone loss, and has been used in this thesis to study the effects of estradiol on bone cells in vivo. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 1995

El overlapping es una técnica de montaje audiovisual donde el sonido se adelanta intencionalmente a la imagen durante el ensamble de dos secuencias. Este procedimiento tiene la finalidad de suavizar la transición de las secuencias vinculadas o, en cambio, hacer notar al máximo posible sus diferencias para provocar impresión de sorpresa. Pese a lo extensivo del uso de este procedimiento en el ámbito de la creación audiovisual no existe investigación empírica que pueda validar estos efectos. Luego de la revisión teórica se efectúa un primer Análisis cualitativo de 235 mensajes overlapping, con el objetivo de definir sus rasgos formales y las variables relevantes asociadas a la impresión emocional. Luego se realiza una segunda aproximación mediante el Análisis Instrumental de cuatro variables relevantes: Variación de la intensidad del sonido, Tiempo del adelantamiento, Ataque sonoro y Variación visual, en una muestra acotada de 51 mensajes. Finalmente, se realiza una prueba experimental para medir los tiempos de reconocimiento semántico de la información audiovisual.Seguidamente, se formulan las hipótesis de investigación. Se diseña el test de recepción, recodificando las variables de análisis para adaptarlas a la prueba experimental. Se modeliza la variable dependiente: Impresión de Sorpresa, empleando una escala de 5 valores, basada en el protocolo de Izard. Se realizan las pruebas estadísticas de contraste. Se obtiene un algoritmo de activación emocional basado en la actuación de tres variables. En la última parte se contrastan las hipótesis y se definen dos tipologías de overlapping a partir de su forma interior y sus efectos de sentido. Finalmente, se desglosan las conclusiones de la tesis y un apartado de discusión metodológica de las pruebas realizadas.Los resultados de la presente investigación indican que el cambio pronunciado de los valores de la intensidad del sonido, la imagen y la información precedente y subsecuente en los mensajes-overlappings producen una elevada impresión emocional en los receptores. Este conocimiento pueder ser útil para mejorar la eficacia de los discusos audiovisuales, desarrollar métodos y tratamientos de montaje explotando el potencial comunicativos contenido en los rasgos estimulares de la imagen y el sonido. / The overlapping is an audiovisual editing technique in which the sound is intentionally put ahead the image during the assembly of two sequences. This proceeding may have the goal of disguising the transition of two sequences connected or, on the contrary, to make it explicit so it provokes great impression of surprise. In spite of the extensive use of this proceeding in the sphere of the audiovisual creation, there no existis empiral research that could validate those effects. After the theoretical revision, it is carried out a Qualitative analysis of 235 overlapping messages, with the objective of defining its formal features and the relevant variables associated to its emotion impression. Then, it is carried out a second approach through an Instrumental Analysis of the 4 relevant variables: variation of the intensity of sound, time of "overtaking", sound stress and visual variation, in an closed sample of 51 messages. Finally, it is carried out an experimental test for measuring the times of semantic recognition of the audiovisual information. Next, the hypothesis of research are formulated, and a reception test is designed, recodifying the variables of analysis for the adaptation to an experimental tril. The dependent variable is modelized: impression of surprise, making use of a 5 values scale, based on the protocol of Izard. The comparative statistics tests are made, and al algorithm of emotional activation is obtained according the variation of the three variables. In the last part, the hypothesis are tested and the two typologies of overlapping are defined according to its formation and the semantic effects. Finally, the conclusions of the thesis are broke down and there is a section for the methodological discussion of the tests carried out. The results of the present research show that the announced change in the values of intensity of the sound, the previous and posterior images and information in the messages-overlapping produce a great emotional impression in the receivers. This knowledge can be useful for the improvement of efficacy in the audiovisual discourses, develop methods and editing techniques by exploting the potential of communication contents in the stimuli features of image and sound.

L'objectiu d'aquesta tesi és elaborar una anàlisi integral de la sostenibilitat en el cas concret dels espais públics de la Regió Metropolitana de Barcelona (RMB). L'anàlisi es desenvolupa en un context social de postmodernitat en què, conjuntament a la proliferació d'un model urbà dispers i de baixa densitat, emergeixen nous processos de participació ciutadana. Per fer-ho, s'ha dut a terme una triangulació metodològica integrant mètodes quantitatius amb mètodes qualitatius per acabar desenvolupant una anàlisi integral de la sostenibilitat dels espais públics urbans. Així, s'ha treballat quantitativament a partir de la digitalització cartogràfica des espais públics enjardinats de la RMB, un l'anàlisi quantitatiu de 315 d'aquests espais i un qüestionari enviat a tots els municipis de la regió; però també s'ha treballat amb metodologies qualitatives a partir de 38 entrevistes en profunditat i 19 observacions d'espais públics urbans.La integració s'ha fet a partir de la discussió de dues aparents paradoxes entorn els espais públics urbans de la RMB. La primera, que he anomenat la paradoxa ambiental, es basa en que els espais públics que es desenvolupen en els nous entorns urbans de baixa densitat segurament tenen un impacte ambiental menor que no pas els espais públics desenvolupats en un entorn en general ambientalment més sostenible com és la ciutat compacta. Són els espais públics de la ciutat compacta els que, tot i tenir un paper naturalitzador més destacat, acostumen a estar constituïts per espècies al·lòctones altament consumidores d'aigua.I la segona paradoxa, que he anomenat la paradoxa sociopolítica, es basa en que en la societat actual, en què sembla ser que emergeix la necessitat de desenvolupar noves formes de democràcia participativa, s'està avançant cap a un model territorial dispers i de baixa densitat on es redueix la presència relativa d'espais públics i, en conseqüència, disminueix un actiu que pot actuar com a element potenciador de capital social i catalitzador d'aquests processos participatius emergents. L'anàlisi s'ha dut a terme des de la lògica de l'Ecologia Política, integrant les dimensions ambiental, econòmica, social i política del concepte de sostenibilitat, amb una visió multiescalar de l'objecte d'estudi i seguint la tradició de la geografia marxista que recentment ha incorporat en la darrera dècada la dimensió ambiental en el seu anàlisi.A partir de l'anàlisi empírica es pot concloure que el model urbà i regional produït en les darreres dècades està relacionat amb les dinàmiques d'acumulació de capital, responent als interessos d'una elit que ha gentrificat el centre de la regió i ha originat la migració d'una bona part de la població de classe mitja i mitja-baixa cap a la perifèria, on la urbanització dispersa és la forma urbana predominant.La tesi conclou que els espais públics de la RMB i la seva evolució recent no han contribuït a millorar la sostenibilitat de la RMB en la mesura que responen a la proliferació d'una construcció socioambiental, la urbanització dispersa, que està associada a una disminució dels espais públics i a una proliferació dels jardineria privada. La manca d'espais públics d'aquests nous entorns urbans redueix els espais de relació potencialment generadors de capital social, fet que redueix el compromís cívic dels seus habitants i dificulta enormement l'èxit de les noves formes de govern participatives que, d'altra banda, s'apunten com les noves formes per a governar l'actual societat complexa. Al mateix temps, la proliferació de jardins privats multiplica el consum d'aigua a la RMB, posant cada cop més en crisi el ja precari equilibri hídric entre oferta i demanda. / The objective of this doctoral dissertationthesis is to developmake an integrated analysis of sustainability of public spaces in the Metropolitan Region of Barcelona (MRB). The analysis is performed under a postmodern developed in a context of post modernity where, the expansion of theat the same time that a low density urban model currently taking place in the MRB is contrasted with the rise of is spreading, new processes of political participationare arising.OTo develop this research, an is one of the significantimportant contributions of this thesis is the integration of has been done, integrating quantitative and qualitative methodologies, leading developing, at the end, towards an integrated assessment of the sustainability of urban public spaces sustainability. On the one handIn one hand, the quantitative work has consisted inI have quantitatively worked obtaining the digital cartography digitalizing the cartography of urban gardened public spaces of the MRB, developing a numericalnumeric analysis of several variables from a sample of 315 of these public spaces, and sending a questionnaire to the 163 municipalities of the MRB. On the other hand, the qualitative work has implied I have qualitatively worked with 38 38 open but detailed interviews with residents of the region, and 19 direct observations of urban public spaces of this areaaround the region.Integration has been approached done from two apparent paradoxes of urban public spaces. The first one, that I have called the environmental paradox, is based on the low environmental impact of public spaces in the sprawled areas, , a urban model where, generally, environmental impacts are very high. However, in the On the contrary, in compact city, a typically more sustainable urban model, urban public spaces are less environmentally sustainable because their dependencein the sense that these urban public spaces on are characterized by a predominance of turf grass, a very high water consumption species that needs therefore massive quantities of this scarce resource in the Mediterranean.in a Mediterranean context.The second paradox, that I have called the socio-political paradox, is based in the fact that while on that nowadays, with an emerging need of new forms of governance based on citizens participation are emerging in the MRB, the also emerging process of urban MRB is going to an urban sprawl model, and the decline of public spaces it implies, erodeswhere public spaces are minimized and, in consequence the potential of these public spaces tois diminishing an active that could generate social capital and thus to facilitate these emergent processes of political participation.The theoretical stance of the dissertation has been largely modelled after aThe analysis has been done from a Political Ecology point of view, following the tradition of Marxist Geography that recently has fully incorporated the environmental dimension in its analysis. The eEnvironmental, economic, social and political dimensions of the sustainability concept have been integrated with a scalar vision of the production of urban public spaces.After the empirical analysis, I can concludeaffirm that the urban and regional model produced in the last decades is related to dynamics of capital accumulation, responding to the interest of an elite that has gentrified the centre of the region and has caused the migration of a part of the population of middle and ow-middle-low income classes to the periphery of the region, where urban sprawl is the predominantce urban form.The thesis concludes that public spaces of the MRB and theirits recent evolution have not contributed much to improve sustainability in the MRB. Public spaces in this regionof the MRB respond to a proliferation of the socio-environmental construction of the urban sprawl. This socio-environmental construction reduces urban public spaces as spaces of relation that could generate social capital. At , at the same time, the that a spread of private gardens is associated with this urban sprawlenvironment, multiplies ying water consumption in of the MRB adding new stresses to an already difficult hidrosocial cycle.

Se pretende conocer su desarrollo arquitectónico a lo largo de su historia y se plantea la relación texto-contexto como básica para el estudio de una población con características muy marcadas; el proyecto arquitectónico, decimos, que puede ser sin representación gráfica en el caso de la arquitectura popu1ar, 1ee el contexto, propone y edifica un texto y el lugar deviene luego de la construcción de un nuevo lugar, un contexto diferente al anterior, a pesar de esto se produce una continuidad ofrecida por el trabajo tipológico de la arquitectura popular y bruscamente interrumpida por las "discontinuidades", el aparecimiento de nuevas tipologías. / ABASTRACTThere are many publications of various types, which mention Cadaqués architecture; those however are in most cases romantic and enthu¬siastic lectures of his architecture.The matter, the author says, is more complicated, it is produced by a series of interactive relationships between the Cadaqués citizens, the economical and political power, the rules, laws and customs that this power produces, and his architecture is a result of this relationship.In history, the economical development, his macro economy and his system, has periods with maximums and minimums, corresponding with the welfare and crisis moments, opposed them in the time also, in which ones, the architecture that has its own independence and autonomy, lost these qualities or there are not the determinants, the economical ones are the determinants in these moments.These periods called "discontinuities" produce new architectonical types, the collective conscious and unconscious works in the direction of welfare and prosperity, the society in his totality works producing more and better, the economical resources contribute to produce bigger and better architectural objects, those ones, are the new types introduced in Cadaqués, like an example, and those built by sensitive artists could mean critical and avant-garde objects.There are others which have not the same kind of work, their authors do not have the same sensibility, and those ones, inside a continued typological work are easily detectable, the do not understand all the architectonic tradition, and their work can not be considered as well integrated.The architectural education should not forget this matter, the history must be present, and the types can be a way to introduce the students to the historical relationship without forgetting our modern culture, our XXth century belonging, and the future of our civilization, the science and technological progress, without loosing our collective memory, our legacy.

Comprendre la globalitat de la ciutat d'avui és difícil i sovint intentem explicar-la a través d'anècdotes o de manera parcial. La tesi proposa analitzar: la necessitat d'estructures formades per espais urbans a les ciutats, i la forma que aquestes ens donen com a mètode per saber que és i com ha de ser un fet urbà. Aquests sistemes son del tot imprescindibles i en ells recau en gran part la forma i la qualitat urbana, per tant la seva absència és sinònim de lloc suburbà. Les estructures estan formades per la combinació racional de llocs públics i el conjunt d'això és un diagrama urbà. Per abordar aquest tema la tesi es composa de dues parts.En la primera part, es descriuen els llocs públics que són fonamentals en algunes ciutats, i és comprova com aquests col·laboren definitivament a la forma urbana. En aquesta part s'analitzen dotze ciutats situades a àmbits geogràfics distints, quatre són asiàtiques, quatres europees i quatre americanes. En la selecció es busca que les ciutats estiguin suficientment allunyades culturalment per tal de que en principi els llocs que siguin estudiats puguin esdevenir elements prou especials de cada situació. Allò realment interesant és el comprovar com aquests espais urbans tenen un valor universal i que son apreciats i utilitzats en distints models de ciutat com a formes habituals de composició de l'estructura de la ciutat.En la segona part, s'analitza la forma del diagrama de la ciutat i com aquest és el seu suport estructural. Per fer-ho sempre es compara l'estructura formada per a llocs públics amb ciutats o parts de ciutats. Es parteix sempre d'allò més elemental, com és una plaça o un carrer, i a través d'un procés de composició urbana es dissenya un sistema complex i urbà. En tot això, la forma dels diagrames resultants és estudiada de maneres diferents i es fan símils amb altres diagrames com son els que hi ha en els taulers de jocs. La possibilitat de fer una forta abstracció de la forma de la ciutat i arribar a conèixer el seu diagrama és essencial. Per això mètodes reductius i/o de comparació que ens ajudin a sintetitzar el problema ens poden ser útils. Els jocs i en especial els diagrames dels seus taulers seran un camí interessant a investigar. Conèixer la ciutat és saber jugar al seu tauler urbà. En conclusió la tesi determina que els diagrames urbans són completament imprescindibles en qualsevol ciutat i la seva absència sols és símptoma de marginalitat. La tesi proposa dos maneres de realitzar diagrames, sempre fets a través de la suma de llocs públics. La primera, és aquella que utilitza llocs bàsics de composició com son les places i els carrers. La segona, és la que es denomina com a campus i proposa una ciutat oberta i de fàcil integració amb la natura. La ciutat ha d'estar sempre recolzada per estructures equivalents a diagrames de llocs públics. Finalment, en l'epíleg, la tesi proposa quasi un petit manual de composició urbana, o si més no alguns elements imprescindibles per a qualsevol ciutat. / It is difficult to understand the present-day city in its totality and we often try to explain it through anecdotes or only partially. The thesis proposes to analyse: the need for structures formed by urban spaces in the cities, and the shape they offer us as a means to knowing what they are and the nature of urban facts. These systems are indispensable and to a great extent urban form and urban quality reside in them; therefore their absence is synonymous to the suburban area. The structures are formed by rational combination of public spaces and the resulting whole is an urban diagram. To tackle this theme the thesis is divided into two parts.In the first part public spaces which are essential to some cities are described, and the way they finally contribute to the urban form is examined. In this part twelve cities from different geographical areas are analysed; four of them are Asian, four are European and another four are American cities. With this selection we are aiming for cities that culturally are far enough apart to allow the chosen spaces to become sufficiently special elements in each situation. The surprise comes when we find out that these urban spaces have a universal value and are appreciated and put into use in different city models as common shapes in composing the city structure.In the second part the form of the city diagram and the way in which the diagram works as the structural support are analysed. To do this the structure formed by public spaces is compared to cities or parts of cities. The most elementary things, like a square or a street, are the starting point, and through a process of urban composition a complex and urban system is designed. The shape of the resulting diagrams is studied in different ways and comparisons are made with other diagrams like the ones there are on game boards. The possibility of making a high-level abstraction of the form of the city and getting to know its diagram is essential. So methods of reduction and/or comparison that help us to synthesise the problem can be useful to us. Games and, in particular, the diagrams of their boards will be interesting paths to explore. Knowing the city knows how to play on the urban board.In conclusion this thesis establishes that urban diagrams are indispensable in any city and that their absence is simply a symptom of marginality. The thesis proposes two ways of creating diagrams, always through the adding up of public spaces. The first one uses basic compositional places like squares and streets. The second is named "campus" and suggests an open city, integrating effortlessly with nature. The city always has to be supported by structures that are equivalent to the diagrams of public spaces. Finally, in the epilogue the thesis offers something like a small "urban composition" manual or some essential elements for any city.