People describe and explore space with a strong emphasis on the visual senses, yet modelling the field of view has received little attention within the realm of Location Based Services (LBS), in part due to the lack of useful data. Advances in data capture, such as Light Detection and Ranging (LiDAR), provide new opportunities to build digital city models and expand the range of applications which use visibility analysis. This thesis capitalises on these advances with the development of a visibility model to support a number of innovative LBS functions in an urban region and particular focus is given to the visibility model‟s supporting role in the formation of referring expressions, the descriptive phrases used to identify objects in a scene, which are relevant when delivering spatial information to the user through a speech based interface. Speech interfaces are particularly useful to mobile users with restricted screen viewing opportunities, such as navigational support for motorists and a wider range of tasks including delivering information to urban pedestrians. As speech recognition accuracies improve so new interaction opportunities will allow users to relate to their surroundings and retrieve information on buildings in view through spoken descriptions. The papers presented in this thesis work towards this goal, by translating spatial information into a form which matches the user‟s perspective and can be delivered over a speech interface. The foundation is the development of a new visual exposure model for use in urban areas, able to calculate a number of metrics about Features of Interest (FOIs), including the façade area visible and the percentage on the skyline. The impact of urban vegetation as a semi-permeable visual barrier is also considered, and how visual exposure calculations may be adjusted to accommodate under canopy and through canopy views. The model may be used by pedestrian LBSs, or applied to vehicle navigation tasks to determine how much of a route ahead is in view for a car driver, identifying the sections with limited visibility or the best places for an overtaking manoeuvre. Delivering information via a speech interface requires FOI positions to be defined according to projective space relating to the user‟s viewpoint, rather than topological or metric space, and this is handled using a new egocentric model. Finally descriptions of the FOIs are considered, including a method to automatically collect façade colours by excluding foreground objects, and a model to determine the most appropriate description to direct the LBS user‟s attention to a FOI in view.

Urban planning has witnessed the profound changes in the methodologies of modelling during the last 50 years. Spatial interaction models have passed from social physics, statistical mechanics to non-spatial and spatial information processing stages of progress that can be designated as paradigm shifts. This thesis traces the Maximum Entropy (MaxEnt) approach in urban planning as pioneered by Wilson (1967,1970) and Spatial Entropy concept by Batty (1974) based on the Information Theory and its developments by Shannon (1948), Jaynes (1957), Kullback (1959) and by Tribus (1962,1969). Information-theoric methods have provided the theoretical foundation for challenging the uncertainty and incomplete information issues concerning the complex urban structure. MaxEnt, as a new logic, gives probabilities maximally noncommittal with regard to missing information. Wilson (1967,1970) has replaced the Newtonian analogy by the entropy concept from statistical mechanics to alleviate the mathematical inconsistency in the gravity model and developed a set of spatial interaction models consistent with the known information. Population density distribution as one of the determinants of the urban structure has been regarded as an exemplar to show the paradigm changes from the analysis of density gradients to the probabilistic description of density distributions by information-theoric methods. Spatial Entropy concept has introduced the spatial dimension to the Information Theory. Thesis applies Spatial Entropy measures to Ankara 1970 and 1990 census data by 34 zones and also obtains Kullback&rsquo / s Information Gain measures for population changes during the two decades. Empirical findings for Spatial Entropy measures show that overall Ankara-1970 and 1990 density distributions are &lsquo / &rsquo / Uneven&rsquo / &rsquo / and the uniform distribution hypothesis is not confirmed. These measures also indicate a tendency towards &ldquo / More Uniformity&rdquo / for density distributions in comparison to 1970. Information Gain measure for population changes also deviates from zero and direct proportionality hypothesis between posterior 1990 and prior 1970 population distributions by zones is not confirmed. Current research is focused on information processing with more engagement in the urban spatial structure and human behavior. This thesis aims to participate with these efforts and concludes that Information Theory has the potential to generate new profound changes in urban planning and modelling processes.

O presente trabalho investiga possibilidades quanto à utilização de dados desagregados, especificamente do Cadastro Nacional de Endereços para Fins Estatísticos (CNEFE) do Instituto Brasileiro de Geografia e Estatística (IBGE), em modelos e análises urbanas. A divulgação do CNEFE representa uma mudança no quadro histórico de escassez de dados a respeito do uso do solo urbano no Brasil. Nesse novo contexto em que a aquisição deste tipo de informação – sem perder de vista suas contingências – deixa de ser uma debilidade em estudos a respeito das cidades brasileiras, apresenta-se nesta dissertação quatro métodos de modelagem e análise sob a perspectiva dos sistemas configuracionais urbanos que lançam mão do CNEFE enquanto insumo. Ao longo de três capítulos com características de artigos, explora-se primeiro a construção de modelos descritivos a partir dos dados; em seguida, busca-se como avaliar a nitidez com que os dois modelos produzidos descrevem o sistema urbano representado; e, por último, discute-se como confrontar os resultados da análise da acessibilidade do sistema urbano com os dados do modelo. Como estudo de caso, utilizou-se a cidade de Ijuí, RS. / This work investigates possibilities regarding the use of disaggregated data, specifically from the National Addressing Record for Statistical Purposes (CNEFE) of the Brazilian Institute of Geography and Statistics (IBGE) in urban modelling and analysis. The release of CNEFE represents a change in the historic scenario of land use data shortage in Brazil. Within this new context, in which the acquisition of this kind of information is no longer a weakness for research on Brazilian cities, this dissertation presents four methods for the construction of urban models and analyses under the perspective of urban configurational systems. Along three paper-like chapters, we first explore the construction of descriptive models with the mentioned data; then, we evaluate how sharply the produced models can describe the represented system; and, at last, we discuss how to confront the results of the accessibility analysis with the data. As a case study, we used the city of Ijuí, in Southern Brazil.

O presente trabalho investiga possibilidades quanto à utilização de dados desagregados, especificamente do Cadastro Nacional de Endereços para Fins Estatísticos (CNEFE) do Instituto Brasileiro de Geografia e Estatística (IBGE), em modelos e análises urbanas. A divulgação do CNEFE representa uma mudança no quadro histórico de escassez de dados a respeito do uso do solo urbano no Brasil. Nesse novo contexto em que a aquisição deste tipo de informação – sem perder de vista suas contingências – deixa de ser uma debilidade em estudos a respeito das cidades brasileiras, apresenta-se nesta dissertação quatro métodos de modelagem e análise sob a perspectiva dos sistemas configuracionais urbanos que lançam mão do CNEFE enquanto insumo. Ao longo de três capítulos com características de artigos, explora-se primeiro a construção de modelos descritivos a partir dos dados; em seguida, busca-se como avaliar a nitidez com que os dois modelos produzidos descrevem o sistema urbano representado; e, por último, discute-se como confrontar os resultados da análise da acessibilidade do sistema urbano com os dados do modelo. Como estudo de caso, utilizou-se a cidade de Ijuí, RS. / This work investigates possibilities regarding the use of disaggregated data, specifically from the National Addressing Record for Statistical Purposes (CNEFE) of the Brazilian Institute of Geography and Statistics (IBGE) in urban modelling and analysis. The release of CNEFE represents a change in the historic scenario of land use data shortage in Brazil. Within this new context, in which the acquisition of this kind of information is no longer a weakness for research on Brazilian cities, this dissertation presents four methods for the construction of urban models and analyses under the perspective of urban configurational systems. Along three paper-like chapters, we first explore the construction of descriptive models with the mentioned data; then, we evaluate how sharply the produced models can describe the represented system; and, at last, we discuss how to confront the results of the accessibility analysis with the data. As a case study, we used the city of Ijuí, in Southern Brazil.