Este trabalho apresenta um sistema de navegação autônoma para veículos terrestres com foco em ambientes não estruturados, tendo como principal meta aplicações em campos abertos com vegetação esparsa e em cenário agrícola. É aplicada visão computacional como sistema de percepção principal utilizando uma câmera estéreo em um veículo com modelo cinemático de Ackermann. A navegação é executada de forma deliberativa por um planejador baseado em malha de estados sobre um mapa de custos e localização por odometria e GPS. O mapa de custos é obtido através de um modelo de ocupação probabilístico desenvolvido fazendo uso de uma OctoMap. É descrito um modelo sensorial para atualizar esta OctoMap a partir da informação espacial proveniente de nuvens de pontos obtidas a partir do método de visão estéreo. Os pontos são segmentados e filtrados levando em consideração os ruídos inerentes da aquisição de imagens e do processo de cálculo de disparidade para obter a distância dos pontos. Os testes foram executados em ambiente de simulação, permitindo a replicação e repetição dos experimentos. A modelagem do veículo foi descrita para o simulador físico Gazebo de acordo com a plataforma real CaRINA I (veículo elétrico automatizado do LRM-ICMC/USP), levando-se em consideração o modelo cinemático e as limitações deste veículo. O desenvolvimento foi baseado no ROS (Robot Operating System) sendo utilizada a arquitetura básica de navegação deste framework a partir da customização dos seus componentes. Foi executada a validação do sistema no ambiente real em cenários com terreno irregular e obstáculos diversos. O sistema apresentou um desempenho satisfatório tendo em vista a utilização de uma abordagem baseada em apenas uma câmera estéreo. Nesta dissertação são apresentados os principais componentes de um sistema de navegação autônoma e as etapas necessárias para a sua concepção, assim como resultados de experimentos simulados e com o uso de um veículo autônomo real / This work presents a system for autonomous vehicle navigation focusing on unstructured environments, with the primary goal applications in open fields with sparse vegetation, unstructured environments and agricultural scenario. Computer vision is applied as the main perception system using a stereo camera in a car-like vehicle with Ackermann kinematic model. Navigation is performed deliberatively using a path planner based on a lattice state space over a cost map with localization by odometry and GPS. The cost map is obtained through a probabilistic occupation model developed making use of an OctoMap. It is described a sensor model to update the spatial occupancy information of the OctoMap from a point cloud obtained by stereo vision. The points are segmented and filtered taking into account the noise inherent in the image acquisition and calculation of disparity to obtain the distance from points. Tests are performed in simulation, allowing replication and repetition of experiments. The modeling of the vehicle is described to be used in the Gazebo physics simulator in accordance with the real platform CaRINA I (LRM-ICMC/USP automated electrical vehicle) taking into account the kinematic model and the limitations of this vehicle. The development is based on ROS (Robot Operating System) and its basic navigation architecture is customized. System validation is performed on real environment in scenarios with different obstacles and uneven terrain. The system shows satisfactory performance considering a simple configuration and an approach based on only one stereo camera. This dissertation presents the main components of an autonomous navigation system and the necessary steps for its conception as well as results of experiments in simulated and using a real autonomous vehicle

The pollution by heavy metals in the roadside soil alteration tendency was thoroughly investigated by applying the complex experimental and statistical environmental analysis and means for pollution by heavy metals and petroleum products reduction by natural zeolite and vermiculite were evaluated and developed. To reach the novelty it was: • The roadside soil pollution by heavy metals, it’s dangerous and pollution variation tendencies were investigated. • The suitability of natural zeolite for heavy metal removal from soil and aquatic solutions was proved. • The suitability of natural zeolite and vermiculite for petroleum products removal from aquatic solutions was proved.

Este trabalho apresenta um sistema de navegação autônoma para veículos terrestres com foco em ambientes não estruturados, tendo como principal meta aplicações em campos abertos com vegetação esparsa e em cenário agrícola. É aplicada visão computacional como sistema de percepção principal utilizando uma câmera estéreo em um veículo com modelo cinemático de Ackermann. A navegação é executada de forma deliberativa por um planejador baseado em malha de estados sobre um mapa de custos e localização por odometria e GPS. O mapa de custos é obtido através de um modelo de ocupação probabilístico desenvolvido fazendo uso de uma OctoMap. É descrito um modelo sensorial para atualizar esta OctoMap a partir da informação espacial proveniente de nuvens de pontos obtidas a partir do método de visão estéreo. Os pontos são segmentados e filtrados levando em consideração os ruídos inerentes da aquisição de imagens e do processo de cálculo de disparidade para obter a distância dos pontos. Os testes foram executados em ambiente de simulação, permitindo a replicação e repetição dos experimentos. A modelagem do veículo foi descrita para o simulador físico Gazebo de acordo com a plataforma real CaRINA I (veículo elétrico automatizado do LRM-ICMC/USP), levando-se em consideração o modelo cinemático e as limitações deste veículo. O desenvolvimento foi baseado no ROS (Robot Operating System) sendo utilizada a arquitetura básica de navegação deste framework a partir da customização dos seus componentes. Foi executada a validação do sistema no ambiente real em cenários com terreno irregular e obstáculos diversos. O sistema apresentou um desempenho satisfatório tendo em vista a utilização de uma abordagem baseada em apenas uma câmera estéreo. Nesta dissertação são apresentados os principais componentes de um sistema de navegação autônoma e as etapas necessárias para a sua concepção, assim como resultados de experimentos simulados e com o uso de um veículo autônomo real / This work presents a system for autonomous vehicle navigation focusing on unstructured environments, with the primary goal applications in open fields with sparse vegetation, unstructured environments and agricultural scenario. Computer vision is applied as the main perception system using a stereo camera in a car-like vehicle with Ackermann kinematic model. Navigation is performed deliberatively using a path planner based on a lattice state space over a cost map with localization by odometry and GPS. The cost map is obtained through a probabilistic occupation model developed making use of an OctoMap. It is described a sensor model to update the spatial occupancy information of the OctoMap from a point cloud obtained by stereo vision. The points are segmented and filtered taking into account the noise inherent in the image acquisition and calculation of disparity to obtain the distance from points. Tests are performed in simulation, allowing replication and repetition of experiments. The modeling of the vehicle is described to be used in the Gazebo physics simulator in accordance with the real platform CaRINA I (LRM-ICMC/USP automated electrical vehicle) taking into account the kinematic model and the limitations of this vehicle. The development is based on ROS (Robot Operating System) and its basic navigation architecture is customized. System validation is performed on real environment in scenarios with different obstacles and uneven terrain. The system shows satisfactory performance considering a simple configuration and an approach based on only one stereo camera. This dissertation presents the main components of an autonomous navigation system and the necessary steps for its conception as well as results of experiments in simulated and using a real autonomous vehicle

This is a case study of a rural school in the Moloto area. The objective of the enquiry is to explore the responses of children to road safety input that they receive at school. Children’s experiences as road users were gathered through intensive interviews with them, their parents and teachers and corroborated by my observation of children using the Moloto road and other arterial roads in the village. The study was informed by the interpretivist paradigm. Road safety education is part of the mainstream curriculum in South African schools but the environment for delivering it effectively is counterproductive in a school that lacks resource materials and trained teachers. The little that is taking place, as the study shows, is class-based, lacks context and focuses on teaching pedestrian skills with no practical input. The community’s unsafe road use behaviour of walking in the middle of the road and crossing the road everywhere undermines whatever road safety skills children might have learnt at home or at school. Key findings of the study are: children’s development of pedestrian skills; children’s constructions of road safety knowledge and their value of life and road signs; the negative influence of the unsafe “road environment”; and children’s attitude to road safety. Although children theoretically know what to do when using the road, in practice they do not show safe road use behaviour. Their construction of road safety knowledge is mainly informed by the practices of the broad community. This paradox between what the literature prescribes, what the national curriculum entails and what the children apply in their everyday use of the roads is the main finding of the study. Although children are enthusiastic about road safety education the same cannot be said about the teachers who are demoralised and not sure whether what they are doing is right or wrong. However, the children understand the value of life and the danger of using the road infrastructure recklessly even though their road use behaviour suggests otherwise. The low level of formal education among parents and the lack of support for teachers from road safety officers do not help the situation. Effective road safety education delivery depends on a number of variables or factors. Where these conditions are not available, the whole process becomes a futile exercise. In conclusion, road safety education can be summarised as a process with sequenced goals: The provision of information about injury risks and how to avoid them, changing attitudes towards risk and safety, and altering behaviour. Training should include the development of clearly defined pedestrian skills through guidance by a more skilled individual and practice in the road environment. Education can thus underpin both legislative and environmental measures by creating a climate of opinion that enhances a culture of safety which is not evident in the Moloto community. It will take political will and resource allocation for road safety education for any meaningful impact to be made in delivering road safety education and pedestrian skills effectively in a rural school like the Moloto primary school in Mpumalanga. / Thesis (PhD)--University of Pretoria, 2010. / Early Childhood Education / unrestricted

INTRODUCTION : Les jeunes de moins de 25 ans constituent le groupe de conducteurs le plus impliqué dans les collisions routières (CR). L’objectif de cette étude est de déterminer l’importance de certains facteurs humains et de l’environnement routier dans les collisions les nuits de la fin de semaine chez les jeunes conducteurs. Les hypothèses postulent des chances plus élevées de CR les nuits de la fin de semaine, comparativement aux CR survenant à d’autres moments de la semaine, en présence d’un seul facteur de risque et de deux facteurs de risque. MÉTHODE : Cette étude transversale porte sur les CR ayant causé des blessures légères, graves ou mortelles au Québec chez les conducteurs âgés de 16 à 24 ans. Les informations sur les 58 478 CR survenus de 2007 à 2011 et les facteurs associés à ces CR proviennent de la banque de données de la Société de l’assurance automobile du Québec. Les CR les nuits de la fin de semaine (vendredi à samedi et samedi à dimanche de 20 h 00 à 04 h 59) sont comparées aux CR survenues aux autres moments de la semaine. L’importance des facteurs humains (p. ex., conduite avec capacités affaiblies) et de l’environnement routier (p. ex., courbes) dans ces CR est évaluée à l’aide d’analyses de régression logistique binaire et multinomiale. RÉSULTATS : Plusieurs facteurs sont liés à une augmentation des chances de CR les nuits de la fin de semaine, comparativement aux autres moments de la semaine. Ces facteurs incluent, par ordre d’importance décroissant : la conduite avec les capacités affaiblies (rapport des cotes ajusté [RCA] = 5,05 et intervalles de confiance à 99 % [IC 99 %] = 4,53‒5,64), la fatigue et le sommeil (RCA = 2,40 ; IC 99 % = 2,12‒2,73), la présence de passagers (RCA = 1,81 ; IC 99 % = 1,69‒1,94), le genre masculin (RCA = 1,36 ; IC 99 % = 1,27‒1,46), les courbes (RCA = 1,21 ; IC 99 % = 1,11‒1,32) et la vitesse (RCA = 1,18 ; IC 99 % = 1,09‒1,28). Les résultats sur la présence de deux de ces facteurs suggèrent l’importance des capacités affaiblies. Les chances de CR sont particulièrement importantes lorsque la présence de capacités affaiblies et d’un autre facteur est comparée à l’absence de ces deux facteurs. Dans ces cas, les chances de CR s’étalent de 5,33 (IC 99 % = 4,40‒6,45) pour la combinaison avec les courbes à 7,68 (IC 99 % = 6,52‒9,05) pour la combinaison avec la présence de passagers. CONCLUSION : Cette étude a permis de déterminer l’importance de plusieurs facteurs de risque, notamment la conduite avec capacités affaiblies, dans l’implication des jeunes conducteurs dans les CR les nuits de la fin de semaine. Les résultats suggèrent diverses stratégies afin de mieux cibler la conduite avec capacités affaiblies, incluant l’accès graduel à la conduite avec de jeunes passagers la nuit après l’obtention du permis de conduire. / Abstract : INTRODUCTION: Young people under 25 represent the group of drivers most involved in motor vehicle crashes (MVC). The aim of this study is to determine the significance of certain human and road environment factors in weekend night crashes involving young drivers. The hypotheses postulate higher odds of crash occurrence on weekend nights, as compared to crashes at other times during the week, when there is the presence of a single risk factor and two risk factors. METHOD: This cross-sectional study examines MVC causing minor, severe or fatal injuries in Quebec drivers aged 16 to 24. The information pertaining to the 58 478 MVC that occurred from 2007 to 2011 and the factors associated with these MVC comes from the databank of the Société de l’assurance automobile du Québec. Weekend night MVC (Friday to Saturday and Saturday to Sunday from 8:00 p.m. to 4:59 a.m.) are compared to MVC occurring at other times of the week. The significance of human factors (e.g., driving under the influence) and road environment factors (e.g., curves) in these crashes is assessed using binary and multinomial logistic regression analyses. FINDINGS: Several factors are associated with the increased odds of an MVC occurring on weekend nights, as compared to other times of the week. These factors include, by order of decreasing significance: driving under the influence (adjusted odds ratio [AOR] = 5.05 and 99% confidence interval [99% CI] = 4.53‒5.64), fatigue and sleep (AOR = 2.40; 99% CI = 2.12‒2.73), presence of passengers (AOR = 1.81; 99% CI = 1.69‒1.94), male gender (AOR = 1.36; 99% CI = 1.27‒1.46), curves (AOR = 1.21; 99% CI = 1.11‒1.32), and speed (AOR = 1.18; 99% CI = 1.09‒1.28). The findings on the presence of two of these factors suggest the significance of driving under the influence. The odds of MVC occurrence are particularly high when the presence of driving under the influence and another factor is compared against the absence of these two factors. In such instances, the odds of MVC occurrence range from 5.33 (99% CI = 4.40‒6.45) when curves are also involved to 7.68 (99% CI = 6.52‒9.05) when passengers are also present. CONCLUSION: This study determined the significance of several risk factors, particularly driving under the influence, in young drivers’ involvement in MVC on weekend nights. The findings suggest various strategies to better target driving under the influence, including gradual access to driving with young passengers at night after obtaining a driver’s licence.