Neste trabalho foram estabelecidos os fundamentos metodológicos baseados na identificação dos fatores de risco, fatores de risco identificados, necessários na elaboração de campanhas de segurança viária, orientados pelas diretrizes estabelecidas no projeto CAST (Campaigns and Awareness-raising Strategies in Traffic Safety), o qual define a identificação do comportamento-problema gerador de acidentes como elemento essencial na definição do objetivo de cada campanha. Não havendo dados estatísticos consistentes e confiáveis dos quais seja possível extrair esta informação, foi necessário identificar os fatores comportamentais que estão na origem de atos inseguros e que devem ser prioritários na elaboração de campanhas de segurança viária. Para o efeito, foi necessário estabelecer uma metodologia que envolveu a utilização de diferentes instrumentos de coleta de dados com o objetivo de identificar os comportamentos-problema, assim como outros fatores relacionados à infraestrutura e ao meio ambiente que poderiam induzir esses comportamentos. Esta metodologia envolveu a aplicação de Grupos Focais que orientaram a elaboração de um questionário voltado para a identificação dos fatores de risco do sistema viário, comportamentos de risco e opiniões relacionados com os tipos de mensagens de campanhas. Este questionário foi posteriormente aplicado a uma amostra de condutores, juntamente com o DBQ – Driver Behaviour Questionnaire, este orientado para a identificação de comportamentos de risco de cada inquirido. A associação desses dois instrumentos permitiu a identificação de fatores de risco no sistema viário, assim como comportamentais de risco habituais e as preferências dos inquiridos sobre tipos e mensagens de campanhas, bem como meios de mídia. A análise estatística dos dados coletados permitiu identificar os seguintes fatores de risco relacionados à via: (1) más condições da infraestrutura da via, (2) más condições de sinalização, (3) más condições dos veículos que trafegam pelas vias, e (4) interação principalmente com pedestres. Foram ainda identificadas as suas opiniões relativamente a comportamentos-problema dos demais usuários do sistema viário, destacando-se os seguintes fatores: (1) sono, (2) bebidas, (3) drogas e (4) mensagens de texto. Quanto à importância das campanhas, os inquiridos consideram que elas devem: (1) ser dirigidas aos fatores de risco identificados, (2) estar associadas a outras ações como fiscalização e (3) seus resultados devem ser divulgados pelos órgãos de governo. Finalmente, acerca das mensagens das campanhas e tipos de mídia utilizados, os inquiridos consideraram que as mensagens devem: (1) utilizar laços afetivos, (2) ser mais impactantes, (3) conter cenas reais, (4) ter finalidade educativa; e as mídias mais adequadas seriam: (1) televisão, (2) internet (com ênfase às redes sociais) e (3) painéis de mensagens variáveis. Quanto ao questionário DBQ, foram identificados sete fatores comportamentais dos próprios inquiridos com maior peso e relação com atos inseguros: (1) Baixo nível de aptidão, (2) Infração, (3) Distração/Inatenção, (4) Condução agressiva, (5) Baixa consciência da situação, (6) Estresse e (7) Adaptação Comportamental. Esses fatores representam os tópicos prioritários que devem ser trabalhados em futuras campanhas. / This research established the methodological principles based on the identification of risk factors necessary for elaboration road safety campaigns, following the guidelines recommended by the CAST (Campaigns and Awareness-raising Strategies in Traffic Safety) project, which defines the identification of main problem behaviors generating accidents as an essential element in the definition of each campaign goal. Since there is no consistent and reliable statistical data proveding this information, it was necessary to identify the behavioral factors that originate unsafe acts and that should be priority in road safety campaigns. In order to achieve this result, it was necessary to establish a methodology involving the use of different data collection tools with the intention of identifying the problem behaviors, as well as other factors related to the infrastructure and environment capable to induce these behaviors. This methodology involved Focus Groups application that directed the elaboration of a questionnaire aiming at a identifing road system risk factors, risky behaviors and opinions regarding the types of campaigns messages. This questionnaire was further applied to a drivers\' sample, together with the DBQ Driver Behavior Questionnaire, which was directed to the identification of risky behaviors of each respondent. The association between these two instruments enabled the identification of road system risk factors, as well as common risky behaviors and the respondents\' preferences about the types of campaign messages and media means. The statistical analysis of the collected data enabled the identification of the following risk factors related to the road system: (1) poor road infrastructure conditions, (2) poor signing conditions, (3) poor vehicle conditions, and (4) interaction mainly with pedestrians. Opinions about problem-behaviors were also identified, stressing the following factors: (1) drowsiness, (2) drink and drive, (3) drugs and medication effects (4) texting driving. Concerning the campaigns importance, the respondents considered that they should: (1) be directed to identified risk factors, (2) be associated to other actions such as enforcement and (3) have its results published by the government entities. Finally, regarding the campaign messages and the used media types, the respondents considered that the messages should: (1) use affective anchors, (2) be more impactful, (3) contain real scenes, (4) have educative purpose; and the most adequate media would be: (1) television, (2) internet (with emphasis to the social networks) and (3) variable message panels. With respect to the DBQ questionnaire, seven behavioral factors based on the respondents own experience were identified as more important and related to unsafe attitudes: (1) poor fitness to drive, (2) violations, (3) distraction/inattention, (4) aggressive driving, (5) poor situation awareness, (6) stress and (7) behavioural adaptation. These factors represented the priority topics that should be handled in future campaigns.

The intense economic growth that Brazil has experienced in recent decades and its consequent explosive motorization process have resulted in an undesirable impact: the continuously increasing trend in traffic fatality numbers. This study presents a research on indicators and indexes with the objective of delivering both overall and disaggregated evidence about the road safety performance and targets in fatality reduction in Brazil at the state level taking the exposure into account. The intention is to support road safety strategic analysis in the country and to contribute to improve this critical scene. The methodological structure of this thesis consists of the following three main parts: (I) diagnosing the road safety situation at the state level using final outcome related information, in particular traffic fatality risk data; (II) setting a target number of traffic fatalities based on the relationship between the exposure level and the number of traffic fatalities in each state; and (III) suggesting domains for improvements based on the research of safety performance indicators representing three domains (road user, environment and vehicle) throughout the states. From a benchmarking point of view, we divided the Brazilian states into three separate clusters in order to provide more realistic state performance comparisons. After a data collection and indicators selection step, Data Envelopment Analysis (DEA) was the method used for executing the different steps, with the application of four different types of models specially developed for the identified research purposes. In addition, by means of bootstrapping the DEA scores we measured the sensitivity of the results to possible variations in the input data, for example concerning data quality and availability. As a result, we provided a road safety diagnosis per state as well as traffic fatality targets according to different perspectives: the entire group of road users (motorized and nonmotorized ones), motor vehicle occupants, and finally a disaggregated performance evaluation by running four separate DEA models (for motorcycle, car, truck and bus). Moreover, the SPI research including a hierarchy of 27 safety performance indicators expressed the states relative performance on the main road safety domains. Lastly, state profiles compiling all this information summarized the \"per state\" findings. / O intenso crescimento econômico que o Brasil tem experimentado nas últimas décadas e seu consequente explosivo processo de motorização resultaram em um impacto indesejado: a tendência contínua do aumento do número de mortes no trânsito. Este estudo apresenta uma pesquisa acerca de índices e indicadores com o objetivo de fornecer evidências gerais e desagregadas sobre o desempenho da segurança viária e metas de redução no número de mortes no Brasil no âmbito estadual, levando a exposição em consideração. A intenção é embasar uma análise estratégica da segurança viária no país e contribuir para melhorar este cenário crítico. A estrutura metodológica desta tese consiste das seguintes três partes principais: (I) diagnóstico da situação da segurança viária no nível estadual utilizando informações relacionadas ao resultado final, em particular dados de risco de morte no trânsito; (II) estabelecer uma meta para o número de mortes no trânsito para cada estado; e (III) sugerir domínios para melhorias baseado em pesquisa de indicadores de desempenho da segurança viária voltada a três domínios (usuário da via, ambiente e veículo). Sob a ótica do benchmarking, dividiram-se os estados brasileiros em três clusters para proporcionar comparações mais realistas dos desempenhos estaduais. Após uma etapa de coleta e seleção de indicadores, utilizou-se o método de Data Envelopment Analyis (DEA) para executar as diferentes etapas, com a aplicação de quatro tipos distintos de modelos especialmente desenvolvidos para os propósitos da pesquisa. Além disso, por meio de bootstrapping dos escores obtidos com a DEA, mediu-se a sensibilidade dos resultados a possíveis variações nos dados de entrada, no que diz respeito a, por exemplo, qualidade e disponibilidade dos dados. Como resultado, propicia-se, a partir de diferentes perspectivas, um diagnóstico da segurança viária por estado, assim como metas no número de mortes: para todo o grupo de usuários (motorizados e não-motorizados), ocupantes de veículos motorizados, e finalmente uma avaliação desagregada por meio de quatro modelos separados (para motocicletas, automóveis, caminhões e ônibus). Adicionalmente, a pesquisa de indicadores de desempenho da segurança considerando a hierarquia de 27 indicadores expressou os desempenhos relativos dos estados nos principais domínios da segurança viária. Por fim, perfis estaduais compilando todas estas informações resumem os resultados para os estados.

En réponse au nombre toujours élevé de décès provoqués par les accidents routiers, l'industrie automobile a fait de la sécurité un sujet majeur de son activité global. Les radars automobiles qui étaient de simples capteurs pour véhicule de confort, sont devenus des éléments essentiels de la norme de sécurité routière. Le domaine de l’automobile est un domaine très exigent en terme de sécurité et les radars automobiles doivent avoir des performances de détection très élevées et doivent répondre à des nombreuses contraintes telles que la facilité de production et/ou le faible coût. Cette thèse concerne le développement d’algorithmes pour la détection et la localisation de piétons et de cyclistes pour des radars automobiles de nouvelle génération. Nous avons proposé une architecture de réseau d'antennes non uniforme optimale et des méthodes d'estimation spectrale à haute résolution permettant d’estimer avec précision la position angulaire des objets à partir de la direction d'arrivée (DoA) de leur réponse. Ces techniques sont adaptées à l'architecture du réseau d'antennes proposé et les performances sont évaluées à l'aide de données radar automobiles simulées et réelles acquises dans le cadre de scénarios spécifiques. Nous avons également proposé un détecteur de cible de collision, basé sur la décomposition en sous-espaces Doppler, dont l'objectif principal est d'identifier des cibles latérales dont les caractéristiques de trajectoire représentent potentiellement un danger de collision. Une méthode de calcul d'attribut de cible est également développée et un algorithme de classification est proposé pour discriminer les piétons, cyclistes et véhicules. Les différents algorithmes sont évalués et validés à l'aide de données radar automobiles réelles sur plusieurs scenarios. / In response to the persistently high number of deaths provoked by road crashes, the automotive industry has promoted safety as a major topic in their global activity. Automotive radars have been transformed from being simple sensors for comfort vehicle, to becoming essential elements of safety standard. The design of new generations automotive radars has to face various constraints and generally proposes a compromise between reliability, robustness, manufacturability, high-performance and low cost. The main objective of this PhD thesis is to design algorithms for the detection and localization of pedestrians and cyclists using new generation automotive radars. We propose an optimal non-uniform antenna array architecture and some high resolution spectral estimation methods to accurately estimate the position of objects from the direction of arrival (DOA) of their responses to the radar. These techniques are adapted to the proposed antenna array architecture and the performance is evaluated using both simulated and real automotive radar data, acquired in the frame of specific scenarios. We propose a collision target detector, based on the orthogonality of angle-Doppler subspaces, whose main goal is to identify lateral targets, whose trajectory features represent potentially a danger of collision. A target attribute calculation method is also developed and classification algorithm is proposed to classify pedestrian, cyclists and vehicles. This classification algorithm is evaluated and validated using real automotive radar data with several scenarios.

A construção e ampliação de rodovias gera impactos significativos ao meio ambiente. Os principais impactos ao meio biótico são a supressão de vegetação, redução da riqueza e abundância de espécies de fauna como decorrência da fragmentação de habitats e aumento dos riscos de atropelamento de animais silvestres e domésticos. O objetivo geral do trabalho foi identificar padrões espaciais nos atropelamentos de fauna silvestre por espécie (nome popular) utilizando ferramentas de análise espacial e machine learning. Especificamente, buscou-se compreender a relação entre atropelamentos de animais silvestres e variáveis que representam características de uso e cobertura do solo e caracterização da rodovia, tais como formação florestal, corpos d\'água, silvicultura, áreas edificadas, velocidade máxima permitida, volume de tráfego, entre outras. Os atropelamentos de fauna silvestre foram analisados por espécie atropelada, a fim de identificar os padrões espaciais dos atropelamentos específicos para cada espécie. As ferramentas de análise espacial empregadas foram a Função K - para determinar o padrão de distribuição dos registros de atropelamento de fauna, o Estimador de Densidade de Kernel - para gerar estimativas de densidade de pontos sobre a rodovia, a Análise de Hotspots - para identificar os trechos mais críticos de atropelamento de fauna e, por fim, o Self-Organizing Maps (SOM), um tipo de rede neural artificial, que reorganiza amostras de dados n-dimensionais de acordo com a similaridade entre elas. Os resultados das análises de padrões pontuais foram importantes para entender que os pontos de atropelamento possuem padrões de distribuição espacial que variam por espécie. Os eventos ocorrem espacialmente agrupados e não estão homogeneamente distribuídos ao longo da rodovia. De maneira geral, os animais apresentam trechos de maior intensidade de atropelamento em locais distintos. O SOM permitiu analisar as relações entre múltiplas variáveis, lineares e não-lineares, tais como são os dados ecológicos, e encontrar padrões espaciais distintos por espécie. A maior parte dos animais foi atropelada próxima de fragmentos florestais e de corpos d\'água, e distante de cultivo de cana-de-açúcar, silvicultura e área edificada. Porém, uma parte considerável das mortes de animais dos tipos com maior número de atropelamentos ocorreu em áreas com paisagem diversificada, incluindo alta densidade de drenagem, fragmentos florestais, silvicultura e áreas edificadas. / The construction and expansion of roads cause significant impacts on the environment. The main potential impacts to biotic environment are vegetation suppression, reduction of the abundance and richness of species due to forest fragmentation and increase of animal (domestic and wildlife) vehicle collisions. The general objective of this work was to identify spatial patterns in wildlife-vehicle collisions individually per species by using spatial analysis and machine learning. Specifically, the relationship between wildlife-vehicle collisions and variables that represent land use and road characterization features - such as forests, water bodies, silviculture, sugarcane fields, built environment, speed limit and traffic volume - was investigated. The wildlife-vehicle collisions were analyzed per species, in order to identify the spatial patterns for each species separately. The spatial analysis tools used in this study were K-Function - to determine the distribution pattern of roadkill, Kernel Density Estimator (KDE) - to identify the location and intensity of hotspots and hotzones. Self-Organizing Maps (SOM), an artificial neural network (ANN), was selected to reorganize the multi-dimensional data according to the similarity between them. The results of the spatial pattern analysis were important to perceive that the point data pattern varies between species. The events occur spatially clustered and are not uniformly distributed along the highway. In general, wildlife-vehicle collsions have their hotzones in different locations. SOM was able to analyze the relationship between multiple variables, linear and non-linear, such as ecological data, and established distinct spatial patterns per each species. Most of the wildlife was run over close to forest area and water bodies, and distant from sugarcane, silviculture and built environments. But a considerable part of the wildlife-vehicle collisions occurred in areas with diverse landscape, including high density of water bodies, silviculture and built environments.

El sistema de señalización vial horizontal para carretera convencional es uno de los elementos del equipamiento viario que guarda mayor relación con la seguridad vial. Por ello, la investigación de nuevos materiales y sistemas de aplicación que contribuyan a la mejora de los parámetros físico-ópticos de las marcas viales es vital para el aumento del nivel de servicio de la carretera y, además, para colaborar en la disminución de la siniestralidad en carretera. Por tal motivo, en la presente tesis doctoral se han estudiado las características esenciales de las marcas viales: visibilidad diurna, visibilidad nocturna, resistencia al deslizamiento y durabilidad en busca de la óptima señalización vial horizontal en carretera convencional. Para ello se han desarrollado tres estudios de investigación en tres campos de prueba ejecutados in-situ en distintas carreteras convencionales. En cada uno de ellos se ha evaluado y se han extraído conclusiones que nos han permitido seguir avanzando en la misma línea de investigación a través de los siguientes estudios. En el primer estudio llevado a cabo, se analizaron 81 combinaciones de materiales, aplicadas en el campo de pruebas in-situ nº 1 localizado en la CV-9006 con tipología de travesía, variando el tipo de material base, el material de post-mezclado, sus dosificaciones y los sistemas de aplicación. Para ello se estudiaron los dos parámetros fundamentales: factor de luminancia β y la retrorreflexión RL en seco, para las probetas recién aplicadas, al mes y a los seis meses de antigüedad. Para el segundo estudio se utilizaron materiales y sistemas de aplicación nuevos consiguiendo 14 probetas en cada sentido de circulación, que forman un total de 28 probetas. Éstas fueron ejecutadas in-situ en la CV-8354 y se analizaron los parámetros esenciales de las marcas viales: factor de luminancia β, retrorreflexión RL en seco y coeficiente de rozamiento SRT. El tercer estudio se compuso de 18 combinaciones de materiales para cada sentido de circulación, con un total de 36 probetas, en el campo de pruebas nº 3 de la carretera CV-904. En este caso, los parámetros característicos analizados de las probetas fueron: factor de luminancia β, coordenadas cromáticas (x,y), coeficiente de luminancia en iluminación difusa Qd, retrorreflexión RL en seco, retrorreflexión RL en húmedo y coeficiente de rozamiento SRT para las 36 probetas recién aplicadas, al mes, a los 6 meses, a los 12 meses y a los 18 meses desde su fabricación. Finalmente, tras el análisis cuantitativo y cualitativo de todos los parámetros fotométricos que caracterizan las marcas viales, se ha conseguido establecer el sistema de señalización vial horizontal óptimo para carretera convencional y sus pautas de comportamiento a lo largo del tiempo.

Στόχος της παρούσας διατριβής είναι η μελέτη των οδικών ατυχημάτων και ο προσδιορισμός των επικίνδυνων θέσεων (μελανών σημείων) στο οδικό δίκτυο της Περιφέρειας Δυτικής Ελλάδας. Πιο συγκεκριμένα, πραγματοποιήθηκε καταγραφή όλων των τροχαίων ατυχημάτων στους Νομούς Αχαΐα, Αιτωλοακαρνανίας και Ηλείας για τη χρονική περίοδο 2000 - 2012. Η συλλογή στοιχείων έγινε από τα κατά τόπους Τμήματα Τροχαίας των Αστυνομικών διευθύνσεων κάθε νομού, για ολόκληρο το οδικό δίκτυο, δηλαδή εθνικό, επαρχιακό και αστικό. Έγινε καταγραφή του κάθε τροχαίου ατυχήματος, του αριθμού νεκρών και τραυματιών, της ημερομηνίας και της ώρας του συμβάντος, της ακριβούς τοποθεσίας, όπως επίσης και των συνθηκών οδοστρώματος και των περιβαλλοντικών συνθηκών που επικρατούσαν τη στιγμή του συμβάντος. Τα στοιχεία που συλλέχθηκαν ομαδοποιήθηκαν κατάλληλα και επεξεργάστηκαν στατιστικά. Στη συνέχεια για κάποια τμήματα των εθνικών οδών της ΠΔΕ έγινε προσδιορισμός των μελανών σημείων με διαφορετικές αριθμητικές και στατιστικές μεθόδους. Δεν έγινε μελέτη των μελανών σημείων για όλο το οδικό δίκτυο της ΠΔΕ καθώς κάτι τέτοιο θα ήταν πέρα από τους σκοπούς της παρούσας διατριβής. / This master thesis aims to study road accidents and identify hotspots at Western Greece Region. First, accidents occurred during 2000 - 2012 at Achaia, Aitoloakarnania and Ilia prefectures were recorded. Each record includes date, time, number of fatalities and injuries, specific location, road and environmental conditions at the moment of the accident. Collected data were grouped and analyzed statistically. Then after reviewing several numerical and statistical methods for hazardous location identification, a selection of methods was made and were applied in order to identify hotspots for some parts of the national road network. Subsequently, conclusions about the condition of the Western Greece Region road network, and the causes of accidents were derived. Finally, proposals for treatment and future research were made.

In the work there is the data presented, that show the condition of automobile road network and road safety problems in Lithuania. The road network and its conditions are analyzed, as well as the means allocated for road building, repairement and supervision. The possibility to realize measures for improving road safety and analysis of compliance of the Lithuanian road safety legislation with that of the European Union.The work consists of four parts.The first part analysis the today’s road safety situation in Lithuania.The second part analyses the road safety factors, the measures for improving road safety.The third part describes the purposes and peculiarities of European Union, relation between Lithuania and EU. There is an analyses Lithuanian and Europe Union road safety legislation.The fourth part analyses the methods for calculating losses at accidents and economic evaluation of the road safety measures. In the research part of the work there is given analysis of the benefit – cost for the road safety improvement measures.

INTRODUCTION : En milieu urbain, l’amélioration de la sécurité des piétons pose un défi de santé publique. Pour chaque décès attribuable aux collisions routières, il y a des centaines de personnes blessées et, dans les pays riches, la diminution du nombre annuel de piétons décédés s’expliquerait en partie par la diminution de la marche. Les stratégies préventives prédominantes n’interviennent pas sur le volume de circulation automobile, un facteur pourtant fondamental. De plus, les interventions environnementales pour améliorer la sécurité des infrastructures routières se limitent habituellement aux sites comptant le plus grand nombre de décès ou de blessés. Cette thèse vise à décrire la contribution des volumes de circulation automobile, des pratiques locales de marche et de la géométrie des routes au nombre et à la répartition des piétons blessés en milieu urbain, et d’ainsi établir le potentiel d’une approche populationnelle orientée vers la reconfiguration des environnements urbains pour améliorer la sécurité des piétons. MÉTHODE : Le devis est de type descriptif et transversal. Les principales sources de données sont les registres des services ambulanciers d’Urgences-santé (blessés de la route), l’enquête Origine-Destination (volumes de circulation automobile), la Géobase du réseau routier montréalais (géométrie des routes) et le recensement canadien (pratiques locales de marche, position socioéconomique). Les analyses descriptives comprennent la localisation cartographique (coordonnées x,y) de l’ensemble des sites de collision. Des modèles de régression multi-niveaux nichent les intersections dans les secteurs de recensement et dans les arrondissements. RÉSULTATS : Les analyses descriptives démontrent une grande dispersion des sites de collision au sein des quartiers. Les analyses multivariées démontrent les effets significatifs, indépendants du volume de circulation automobile, de la présence d’artère(s) et d’une quatrième branche aux intersections, ainsi que du volume de marche dans le secteur, sur le nombre de piétons blessés aux intersections. L’analyse multi-niveaux démontre une grande variation spatiale de l’effet du volume de circulation automobile. Les facteurs environnementaux expliquent une part substantielle de la variation spatiale du nombre de blessés et du gradient socioéconomique observé. DISCUSSION : La grande dispersion des sites de collision confirme la pertinence d’une approche ne se limitant pas aux sites comptant le plus grand nombre de blessés. Les résultats suggèrent que des stratégies préventives basées sur des approches environnementales et populationnelle pourraient considérablement réduire le nombre de piétons blessés ainsi que les inégalités observées entre les quartiers. / INTRODUCTION: In an urban environment, improving pedestrian safety is a public health challenge. For every death attributable to road injuries, there are hundreds of injured people and, in richer countries, decreases in the number of pedestrian deaths may reflect a reduction of walking as a mode of transportation. The predominant preventive strategies have limited or no effect on traffic volume, which is the most important predictor of the number of pedestrians injured by motor vehicles. Moreover, environmental interventions are usually limited to sites that have had the greatest number of deaths or injuries. The purpose of this thesis is to describe the contribution of environmental factors such as traffic volume, local walking practices and street geometry, on the number and the distribution of pedestrian injuries in an urban setting. METHOD: The design of the study is descriptive and cross-sectional. The main data sources were Urgences-santé ambulance service records (road injuries), the Origin-Destination survey (traffic volume), the Geobase for the Montreal road network (street geometry) and the census of Canada (local walking practices, socioeconomic status). The descriptive analyses included map locations (x, y coordinates) for all collision sites. Multi-level regression models nested intersections in census sectors and in boroughs. RESULTS: The descriptive analyses showed a great deal of dispersion of collision sites within neighbourhoods. The multivariate analyses showed the significant effects, independent of traffic volume, of the presence of an artery and of a fourth leg at the intersection, and of pedestrian volume in the neighbourhood, on the number of pedestrian injuries at intersections. The multi-level analysis showed extensive spatial variation in the effect of traffic volume. This spatial variation in the number of casualties, and the socioeconomic gradient observed, were in large part explained by traffic volume, the presence of an artery and of a fourth leg at the intersection. DISCUSSION: The great dispersion of collision sites supports an approach which is not limited to sites with the highest number of injured pedestrians. This thesis suggests that preventive strategies based on environmental and population approaches could considerably reduce the number of injured pedestrians , as well as road injury inequalities across urban neighbourhoods.

Road accidents represent a serious social problem and are one of the leading causes of human death and disability on a global scale. To reduce the risk and severity of a road accident, a variety of new safety applications can be realized through wireless communications among vehicles driving nearby each other, or among vehicles and especially deployed road side units (RSUs), a technology known as a vehicular ad hoc network (VANET). Most of the VANET-enabled safety applications are based on broadcasting of safety messages by vehicles or RSUs, either periodically or in case of an unexpected event, such as a hard brake or dangerous road condition detection. Each broadcast safety message should be successfully delivered to the surrounding vehicles and RSUs without any excess delay, which is one of the main functions of a medium access control (MAC) protocol proposed for VANETs. This thesis presents VeMAC, a new multichannel time division multiple access (TDMA) protocol specifically designed to support the high priority safety applications in a VANET scenario. The ability of the VeMAC protocol to deliver periodic and event-driven safety messages in VANETs is demonstrated by a detailed delivery delay analysis, including queueing and service delays, for both types of safety messages. As well, computer simulations are conducted by using MATLAB, the network simulator ns-2, and the microscopic vehicle traffic simulator VISSIM, in order to evaluate the performance of the VeMAC protocol, in comparison with the IEEE 802.11p standard and the ADHOC MAC protocol (another TDMA protocol proposed for ad hoc networks). A real city scenario is simulated and different performance metrics are evaluated, including the network goodput, protocol overhead, channel utilization, protocol fairness, probability of a transmission collision, and safety message delivery delay. It is shown that the VeMAC protocol considerably outperforms the existing MAC schemes, which have significant limitations in supporting VANET safety applications. In addition to enhancing road safety, in-vehicle Internet access is one of the main applications of VANETs, which aims at providing the vehicle passengers with a low-cost access to the Internet via on-road gateways. This thesis presents a new strategy for deploying Internet gateways on the roads, in order to minimize the total cost of gateway deployment, while ensuring that a vehicle can connect to an Internet gateway (using multihop communications) with a probability greater than a specified threshold. This cost minimization problem is formulated by using binary integer programming, and applied for optimal gateway placement in a real city scenario. To the best of our knowledge, no previous strategy for gateway deployment has considered the probability of multihop connectivity among the vehicles and the deployed gateways. In order to allow a vehicle to discover the existence of an Internet gateway and to communicate with the gateway via multihops, a novel data packet routing scheme is proposed based on the VeMAC protocol. The performance of this cross-layer design is evaluated for a multichannel VANET in a highway scenario, mainly in terms of the end-to-end packet delivery delay. The packet queueing at each relay vehicle is considered in the end-to-end delay analysis, and numerical results are presented to study the effect of various parameters, such as the vehicle density and the packet arrival rate, on the performance metrics. The proposed VeMAC protocol is a promising candidate for MAC in VANETs, which can realize many advanced safety applications to enhance the public safety standards and improve the safety level of drivers/passengers and pedestrians on roads. On the other hand, the proposed gateway placement strategy and packet routing scheme represent a strong step toward providing reliable and ubiquitous in-vehicle Internet connectivity.

Older Australians walk for many reasons: health, recreation and transport. However, road safety statistics show that pedestrians over 65 represent one-third of Australia's pedestrian deaths. As Australia's population ages in place and older people take up a walking regime for health and transportation reasons, they need a supportive suburban setting. Urban design theories discuss such "pedestrian-friendly" concepts as sense of place, sense of community, responsive environments, traditional neighbourhood design, transit-oriented development, and crime prevention through environmental design. To investigate these concepts in relation to older pedestrians, this study brings together two areas of literature - research into older pedestrians in relation to urban design theories. Qualitative research methods were used in two case studies, to reveal how older people's interpretation of their local walking environment relates to urban design theories concerning walkable suburbs. The two Brisbane suburbs of Bulimba and Forest Lake were chosen for study, as they have different histories, topographies, street patterns, and other variations. Analysis of key themes gathered from two focus group discussions, one from each suburb, revealed the significance for participants of social interaction when walking for health. A photographic exercise performed by the Forest Lake focus group provided pictorial information for analysis, and revealed participants' interest in the lake's fauna and flora, and in its ongoing maintenance. The study was limited by an unforeseen failure to obtain the cooperation of the Bulimba group in the photographic exercise. In support of the claims made in the literature review, it seems that when older pedestrians walk through suburban streets, they avoid steep hills, busy roads, and intersections where possible, and require footpaths with even surfaces and shelters. When walking for health reasons, participants in this study did not favour local streets, but preferred "natural" places designed exclusively for walkers. Forest Lake participants stated a preference for driving to places they deemed suitable for walking, which suggests a need for more detailed design attention to the urban design qualities of local streets, so that those older people without cars are not disadvantaged.