Made available in DSpace on 2014-12-17T14:55:05Z (GMT). No. of bitstreams: 1 AndersonASS_TESE.pdf: 3250611 bytes, checksum: 4e87cd6efd2a74f4715e56d6e2aa0064 (MD5) Previous issue date: 2012-08-03 / This work introduces a new method for environment mapping with three-dimensional information from visual information for robotic accurate navigation. Many approaches of 3D mapping using occupancy grid typically requires high computacional effort to both build and store the map. We introduce an 2.5-D occupancy-elevation grid mapping, which is a discrete mapping approach, where each cell stores the occupancy probability, the height of the terrain at current place in the environment and the variance of this height. This 2.5-dimensional representation allows that a mobile robot to know whether a place in the environment is occupied by an obstacle and the height of this obstacle, thus, it can decide if is possible to traverse the obstacle. Sensorial informations necessary to construct the map is provided by a stereo vision system, which has been modeled with a robust probabilistic approach, considering the noise present in the stereo processing. The resulting maps favors the execution of tasks like decision making in the autonomous navigation, exploration, localization and path planning. Experiments carried out with a real mobile robots demonstrates that this proposed approach yields useful maps for robot autonomous navigation / Este trabalho apresenta um novo m?todo de mapeamento de ambientes com rob?s m?veis com informa??es tridimensionais para navega??o. Muitas abordagens de mapeamento 3D, usam o m?todo em grade de ocupa??o, o que resulta no uso de muito recurso computacional tanto na constru??o como no armazenamento desses mapas. A presente pesquisa apresenta o mapeamento 2,5-D em grade de ocupa??o-eleva??o, a qual ? definida como uma representa??o discreta, onde cada c?lula armazena uma probabilidade de ocupa??o, a altura do espa?o mapeado e a vari?ncia desse valor de altura. Essa representa??o permite que um rob? m?vel tenha a ci?ncia se um lugar do seu ambiente est? ocupado por um obst?culo e qual a altura desse obst?culo. Dessa forma, ele pode decidir se ? poss?vel navegar sobre o obst?culo ou n?o, de acordo com suas habilidades motoras. As informa??es sensoriais necess?rias para construir o mapa s?o providas por um sistema de vis?o est?reo, o qual foi modelado atrav?s de uma robusta an?lise estat?stica, considerando os ru?dos presentes no processamento est?reo. Os mapas resultantes favorecem a execu??o de tarefas como tomadas de decis?es na navega??o aut?noma, explora??o, localiza??o e planejamento de caminhos. Experimentos pr?ticos reais mostram que o m?todo de mapeamento apresentado ? ?til para a navega??o de rob?s aut?nomos

Made available in DSpace on 2014-12-17T14:55:44Z (GMT). No. of bitstreams: 1 AllanDGA_DISSERT.pdf: 1992696 bytes, checksum: 87d8b1dbc6fe4df6df2f85f90481f9be (MD5) Previous issue date: 2010-01-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aims to seek a more viable alternative for the calculation of differences in images of stereo vision, using a factor that reduces heel the amount of points that are considered on the captured image, and a network neural-based radial basis functions to interpolate the results. The objective to be achieved is to produce an approximate picture of disparities using algorithms with low computational cost, unlike the classical algorithms / O presente trabalho visa buscar uma alternativa mais vi?vel para o c?lculo das disparidades em imagens de vis?o est?reo, utilizando um fator de salto que reduz a quantidade de pontos que s?o considerados da imagem capturada, e uma rede neural baseada em fun??es de base radial para interpolar os resultados obtidos. O objetivo a ser alcan?ado ? produzir uma imagem de disparidades aproximada da real com algoritmos de baixo custo computacional, diferentemente dos algoritmos tradicionais

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-12-15T16:27:02Z No. of bitstreams: 1 ManoelPedroDeMedeirosNeto_DISSERT.pdf: 3664081 bytes, checksum: f1856f73174bde3b90b40604d7d1ae0e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-12-15T16:36:27Z (GMT) No. of bitstreams: 1 ManoelPedroDeMedeirosNeto_DISSERT.pdf: 3664081 bytes, checksum: f1856f73174bde3b90b40604d7d1ae0e (MD5) / Made available in DSpace on 2016-12-15T16:36:27Z (GMT). No. of bitstreams: 1 ManoelPedroDeMedeirosNeto_DISSERT.pdf: 3664081 bytes, checksum: f1856f73174bde3b90b40604d7d1ae0e (MD5) Previous issue date: 2016-02-29 / Ve?culos n?o tripulados est?o cada vez mais presentes no cotidiano das empresas e das pessoas, pois esse tipo de ve?culo est? de forma crescente desempenhando atividades que anteriormente eram apenas executadas por seres humanos. No entanto, para se compreender melhor o potencial de ve?culos n?o tripulados, ? importante conhecer seus tipos, caracter?sticas, aplica??es, limita??es e desafios, pois somente com esse conhecimento pode-se entender as potencialidades do uso de ve?culos dessa natureza em aplica??es variadas. Nesse contexto, na primeira parte desta pesquisa foram estudados os diferentes tipos de ve?culos n?o tripulados, i.e. terrestres, aqu?ticos, a?reos e h?bridos. Durante a segunda fase da pesquisa, foi realizado um aprofundamento tendo como foco as interfaces de usu?rio para controle dos ve?culos a?reos n?o tripulados. Esses dois levantamentos iniciais do dom?nio, permitiram a identifica??o de desafios e oportunidades para o desenvolvimento de novas aplica??es para esse contexto. Com base no conhecimento adquirido com esses estudos, ent?o, foi desenvolvido um sistema de entrega automatizada de objetos para o campus de Universidades, denominado de PostDrone University, e desenvolvido um ve?culo a?reo n?o tripulado para realizar as entregas, denominado de PostDrone University UAV K-263. O sistema possui uma interface de usu?rio de f?cil uso, que n?o requer conhecimentos de dom?nios espec?ficos como avia??o ou controle de aeronaves para sua opera??o. Por fim, diversos testes foram realizados com o intuito de validar e identificar as limita??es da solu??o desenvolvida nesta pesquisa. / Unmanned vehicles are increasingly present in the daily of companies and people, because this kind of vehicle is performing ever more tasks that were previously only executed by human beings. However, to better understand the potential of unmanned vehicles, it is important to know their types, features, applications, limitations and challenges, thus with this knowledge it is possible to comprehend the possibilities of use of these vehicles in several applications. In this context, the first step of the present research consists in studying the different kinds of unmanned vehicles, i.e., ground, surface and underwater, aerial, and hybrid. During the second step of the research, a deepening study was accomplished, with focus on user interfaces of unmanned aerial vehicles. These two initial reviews of the domain allowed the identification of challenges and opportunities to the development of new applications for this context. Based on the acquired knowledge from these studies, then, an automated goods delivery system was developed for universities? campuses, called PostDrone University, and an unmanned vehicle to make the deliveries, called PostDrone University UAV K-263, was also developed. The system has an easy use UI, which does not require the user to have knowledge about specific domains, as aviation or aircraft control, for the operation of the system. Lastly, several test were accomplished aiming to validate the solution proposed in the present research and identify its limitations / 2018-03-31

Information and communication systems enter an increasing number of areas of daily lives. Our reliance and dependence on the functioning of such systems is rapidly growing together with the costs and the impact of system failures. At the same time the complexity of hardware and software systems extends to new limits as modern hardware architectures become more and more parallel, dynamic and heterogenous. These trends demand for a closer integration of formal methods and system engineering to show the correctness of complex systems within the design phase of large projects. The goal of this thesis is to introduce a formal holistic approach for modeling, analysis and synthesis of parallel systems that potentially addresses complex system behavior at any layer of the hardware/software stack. Due to the complexity of modern hardware and software systems, we aim to have a hierarchical modeling framework that allows to specify the behavior of a parallel system at various levels of abstraction and that facilitates designing complex systems in an iterative refinement procedure, in which more detailed behavior is added successively to the system description. In this context, the major challenge is to provide modeling formalisms that are expressive enough to address all of the above issues and are at the same time amenable to the application of formal methods for proving that the system behavior conforms to its specification. In particular, we are interested in specification formalisms that allow to apply formal verification techniques such that the underlying model checking problems are still decidable within reasonable time and space bounds. The presented work relies on an exogenous modeling approach that allows a clear separation of coordination and computation and provides an operational semantic model where formal methods such as model checking are well suited and applicable. The channel-based exogenous coordination language Reo is used as modeling formalism as it supports hierarchical modeling in an iterative top-down refinement procedure. It facilitates reusability, exchangeability, and heterogeneity of components and forms the basis to apply formal verification methods. At the same time Reo has a clear formal semantics based on automata, which serve as foundation to apply formal methods such as model checking. In this thesis new modeling languages are presented that allow specifying complex systems in terms of Reo and automata models which yield the basis for a holistic approach on modeling, verification and synthesis of parallel systems. The second main contribution of this thesis are tailored branching-time and alternating time temporal logics as well as corresponding model checking algorithms. The thesis includes results on the theoretical complexity of the underlying model checking problems as well as practical results. For the latter the presented approach has been implemented in the symbolic verification tool set Vereofy. The implementation within Vereofy and evaluation of the branching-time and alternating-time model checker is the third main contribution of this thesis.

Information and communication systems enter an increasing number of areas of daily lives. Our reliance and dependence on the functioning of such systems is rapidly growing together with the costs and the impact of system failures. At the same time the complexity of hardware and software systems extends to new limits as modern hardware architectures become more and more parallel, dynamic and heterogenous. These trends demand for a closer integration of formal methods and system engineering to show the correctness of complex systems within the design phase of large projects. The goal of this thesis is to introduce a formal holistic approach for modeling, analysis and synthesis of parallel systems that potentially addresses complex system behavior at any layer of the hardware/software stack. Due to the complexity of modern hardware and software systems, we aim to have a hierarchical modeling framework that allows to specify the behavior of a parallel system at various levels of abstraction and that facilitates designing complex systems in an iterative refinement procedure, in which more detailed behavior is added successively to the system description. In this context, the major challenge is to provide modeling formalisms that are expressive enough to address all of the above issues and are at the same time amenable to the application of formal methods for proving that the system behavior conforms to its specification. In particular, we are interested in specification formalisms that allow to apply formal verification techniques such that the underlying model checking problems are still decidable within reasonable time and space bounds. The presented work relies on an exogenous modeling approach that allows a clear separation of coordination and computation and provides an operational semantic model where formal methods such as model checking are well suited and applicable. The channel-based exogenous coordination language Reo is used as modeling formalism as it supports hierarchical modeling in an iterative top-down refinement procedure. It facilitates reusability, exchangeability, and heterogeneity of components and forms the basis to apply formal verification methods. At the same time Reo has a clear formal semantics based on automata, which serve as foundation to apply formal methods such as model checking. In this thesis new modeling languages are presented that allow specifying complex systems in terms of Reo and automata models which yield the basis for a holistic approach on modeling, verification and synthesis of parallel systems. The second main contribution of this thesis are tailored branching-time and alternating time temporal logics as well as corresponding model checking algorithms. The thesis includes results on the theoretical complexity of the underlying model checking problems as well as practical results. For the latter the presented approach has been implemented in the symbolic verification tool set Vereofy. The implementation within Vereofy and evaluation of the branching-time and alternating-time model checker is the third main contribution of this thesis.

Made available in DSpace on 2014-12-17T15:47:49Z (GMT). No. of bitstreams: 1 NatalHC.pdf: 2764921 bytes, checksum: 846252ab05f6de9b65d1cf7bbe1aba09 (MD5) Previous issue date: 2008-08-04 / In this work we propose a technique that uses uncontrolled small format aerial images, or SFAI, and stereohotogrammetry techniques to construct georeferenced mosaics. Images are obtained using a simple digital camera coupled with a radio controlled (RC) helicopter. Techniques for removing common distortions are applied and the relative orientation of the models are recovered using projective geometry. Ground truth points are used to get absolute orientation, plus a definition of scale and a coordinate system which relates image measures to the ground. The mosaic is read into a GIS system, providing useful information to different types of users, such as researchers, governmental agencies, employees, fishermen and tourism enterprises. Results are reported, illustrating the applicability of the system. The main contribution is the generation of georeferenced mosaics using SFAIs, which have not yet broadly explored in cartography projects. The proposed architecture presents a viable and much less expensive solution, when compared to systems using controlled pictures / No presente trabalho, descrevemos uma metodologia para a constru??o de mosaicos georreferenciados a partir de imagens a?reas de pequeno formato, ou SFAI, consideradas n?o controladas. T?cnicas de Est?reo-Fotogrametria e de Vis?o Computacional s?o aplicadas para auxiliarem em resultados de qualidade e confiabilidade. As imagens s?o obtidas atrav?s de uma c?mera digital comum acoplada a um helic?ptero aeromodelo. T?cnicas para eliminar distor??es comuns s?o aplicadas e a orienta??o relativa dos modelos ? realizada baseada na geometria projetiva. Pontos reais do terreno s?o usados para executar a orienta??o absoluta, al?m de uma defini??o de escala e de um sistema de coordenadas que relaciona a imagem medida no terreno. O mosaico ser? manipulado em um SIG, fornecendo informa??o ?til a diferentes tipos de usu?rios, tais como pesquisadores, institui??es governamentais, pescadores e empresas de turismo. Resultados s?o gerados, ilustrando a aplicabilidade do sistema. A principal contribui??o ? a gera??o de mosaicos georreferenciados usando imagens a?reas de pequeno formato, o que tem sido pouqu?ssimo explorado em projetos de cartografia. A arquitetura proposta apresenta uma solu??o vi?vel e bem barata quando comparada com sistemas que utilizam imagens controladas

Made available in DSpace on 2014-12-17T14:55:03Z (GMT). No. of bitstreams: 1 JoaoPAB.pdf: 1121359 bytes, checksum: 0140c2cdd16358b4d1f4ee69b79c5b3c (MD5) Previous issue date: 2006-05-19 / Large efforts have been maden by the scientific community on tasks involving locomotion of mobile robots. To execute this kind of task, we must develop to the robot the ability of navigation through the environment in a safe way, that is, without collisions with the objects. In order to perform this, it is necessary to implement strategies that makes possible to detect obstacles. In this work, we deal with this problem by proposing a system that is able to collect sensory information and to estimate the possibility for obstacles to occur in the mobile robot path. Stereo cameras positioned in parallel to each other in a structure coupled to the robot are employed as the main sensory device, making possible the generation of a disparity map. Code optimizations and a strategy for data reduction and abstraction are applied to the images, resulting in a substantial gain in the execution time. This makes possible to the high level decision processes to execute obstacle deviation in real time. This system can be employed in situations where the robot is remotely operated, as well as in situations where it depends only on itself to generate trajectories (the autonomous case) / Grandes esfor?os t?m sido despendidos pela comunidade cient?fica em tarefas de locomo??o de rob?s m?veis. Para a execu??o deste tipo de tarefa, devemos desenvolver no rob? a habilidade de navega??o no ambiente de forma segura, isto ?, sem que haja colis?es contra objetos. Para que isto seja realizado, faz-se necess?rio implementar estrat?gias que possibilitem a detec??o de obst?culos. Neste trabalho, abordamos este problema, propondo um sistema capaz de coletar informa??es sensoriais e estimar a possibilidade de ocorr?ncia de obst?culos no percurso de um rob? m?vel. C?meras est?reo, posicionadas paralelamente uma ? outra, numa estrutura acoplada ao rob?, s?o empregadas como o dispositivo sensorial principal, pos- sibilitando a gera??o de um mapa de disparidades. Otimiza??es de c?digo e uma estrat?gia de redu??o e abstra??o de dados s?o aplicadas ?s imagens, resultando num ganho substancial no tempo de execu??o. Isto torna poss?vel aos processos de decis?o de mais alto n?vel executar o desvio de obst?culos em tempo real. Este sistema pode ser empregado em situa??es onde o rob? seja tele-operado, bem como em situa??es onde ele dependa de si pr?prio para gerar trajet?rias (no caso aut?nomo)

Made available in DSpace on 2014-12-17T14:55:09Z (GMT). No. of bitstreams: 1 JoseSASS.pdf: 1375081 bytes, checksum: 1561bdbc1ba8feb7671abf9ebca84641 (MD5) Previous issue date: 2007-04-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work proposes a method to determine the depth of objects in a scene using a combination between stereo vision and self-calibration techniques. Determining the rel- ative distance between visualized objects and a robot, with a stereo head, it is possible to navigate in unknown environments. Stereo vision techniques supply a depth measure by the combination of two or more images from the same scene. To achieve a depth estimates of the in scene objects a reconstruction of this scene geometry is necessary. For such reconstruction the relationship between the three-dimensional world coordi- nates and the two-dimensional images coordinates is necessary. Through the achievement of the cameras intrinsic parameters it is possible to make this coordinates systems relationship. These parameters can be gotten through geometric camera calibration, which, generally is made by a correlation between image characteristics of a calibration pattern with know dimensions. The cameras self-calibration allows the achievement of their intrinsic parameters without using a known calibration pattern, being possible their calculation and alteration during the displacement of the robot in an unknown environment. In this work a self-calibration method based in the three-dimensional polar coordinates to represent image features is presented. This representation is determined by the relationship between images features and horizontal and vertical opening cameras angles. Using the polar coordinates it is possible to geometrically reconstruct the scene. Through the proposed techniques combination it is possible to calculate a scene objects depth estimate, allowing the robot navigation in an unknown environment / Este trabalho prop?e um m?todo para determinar a profundidade de objetos em cena utilizando uma combina??o das t?cnicas de vis?o est?reo e autocalibra??o. Determinando a dist?ncia relativa entre objetos visualizados e um rob? m?vel, dotado de uma cabe?a est?reo, ? poss?vel efetuar sua navega??o em ambientes desconhecidos. As t?cnicas de vis?o est?reo fornecem uma medida de profundidade a partir da combina??o de duas ou mais imagens de uma mesma cena. Para a obten??o de estimativas da profundidade dos objetos presentes nesta cena ? necess?rio uma reconstru??o da geometria da mesma. Para tal reconstru??o ? necess?rio o relacionamento das coordenadas tridimensionais do mundo com as coordenadas bidimensionais das imagens. Atrav?s da obten??o dos par?metros intr?nsecos das c?meras ? poss?vel fazer o relacionamento entre os sistemas de coordenadas. Estes par?metros podem ser obtidos atrav?s da calibra??o geom?trica das c?meras, a qual ? geralmente feita atrav?s da visualiza??o de um objeto padr?o de calibra??o com dimens?es conhecidas. A autocalibra??o das c?meras permite a obten??o dos par?metros intr?nsecos das mesmas sem a utiliza??o de um padr?o conhecido de calibra??o, sendo poss?vel a obten??o e a altera??o destes durante o deslocamento do rob? m?vel em um ambiente desconhecido. ? apresentado neste trabalho um m?todo de autocalibra??o baseado na representa??o de caracter?sticas da imagem por coordenadas polares tridimensionais. Estas s?o determinadas relacionando-se caracter?sticas das imagens com os ?ngulos de abertura horizontal e vertical das c?meras. Utilizando-se estas coordenadas polares ? poss?vel efetuar uma reconstru??o geom?trica da cena de forma precisa. Atrav?s desta combina??o das t?cnicas proposta ? poss?vel obter-se uma estimativa da profundidade de objetos cena, permitindo a navega??o de um rob? m?vel aut?nomo em um ambiente desconhecido

The quality of the processes involved in language regeneration strategy formation is critical to the creation of an effective language regeneration strategy and this, in turn, is critical to the achievement of successful language regeneration outcomes. The overall aim of this research project was to evaluate, using a range of effectiveness criteria, the processes involved in the creation of a marae-based te reo Māori regeneration strategy in the hope that others involved in similar projects in the future would benefit and in the hope that the Whakamārama whānau will themselves derive benefit from it in reviewing what has already been achieved. In Chapter 1, the background to the research project and its rationale are outlined and the research questions and research methods are introduced. Chapter 2 provides a critical review of selected literature in the area of strategic planning aspects of language regeneration and relevant aspects of mātauranga Māori. Using an ethnographic approach, the processes and immediate outcomes (in terms of a survey report and a regeneration plan for Whakamārama marae) of the language regeneration project are outlined in Chapter 3. In Chapter 4, effectiveness criteria are derived on the basis of the literature review in Chapter 2. These include criteria relating to leadership, participation, Kaupapa Māori values, environmental analysis and outcomes. The criteria are then applied to the analysis and evaluation of the processes and outcomes outlined in Chapter 3 in order to identify their strengths and weaknesses. The overall conclusion is that Whakamārama's language regeneration activities to date can be regarded as successful in many ways, including the fact that they have resulted in the production of high quality documentation that is widely appreciated by the whānau in the form of a maraebased language survey and a marae-based te reo Māori regeneration plan. Working voluntarily and often under difficult circumstances, core group members demonstrated that they possessed the essential characteristics of commitment, motivation and determination, in addition to the willingness and ability to use existing skills and knowledge effectively and to develop further skills and knowledge as the project proceeded. Perhaps most important, they developed a caring and effective working culture. However, the weaknesses of the project included a lack of preparation and planning prior to the commencement of the project which resulted in a build up of work at a number of stages. This, in turn, lead to delays in producing outcomes and some loss of momentum. It also led, indirectly, to the views of two or three members of the core group being overrepresented in the reo plan goals. The information and analysis provided here have relevance to any language community involved in micro-level language regeneration activities of a similar type. It is hoped therefore that this thesis may help others to not only avoid the problems experienced by the Whakamārama whānau but also to benefit from their successes.

Non esistono dati statistici certi sul numero totale di donne nigeriane trafficate annualmente in Italia ed introdotte nel mercato del sesso. Di fronte a questo ampio numero oscuro, bisogna porsi delle domande: cosa succede alla vittima di tratta quando non trova alcuna forma di aiuto o assistenza sociale? Cosa avviene quando non riesce ad uscire dal mercato del sesso? Secondo testimoni diretti e fonti ufficiali, tra le attuali madams vi sono anche ex vittime che hanno fatto carriera nella gerarchia della tratta e dentro le organizzazioni criminali. La mobilità femminile verso il lato gestionale di questo crimine rappresenta la caratteristica più rilevante della tratta di matrice nigeriana: vale a dire, le vittime sono condotte nel corso del tempo a svolgere una parte attiva nel complesso progetto criminale. Questo elemento distintivo al modello nigeriano richiede un’analisi approfondita, tramite nuovi approcci intesi a sottolineare: a) le aree grigie del mercato della tratta; b) i ruoli intermedi che gli individui ricoprono all'interno del modello vittima/reo; c) la mobilità femminile nella gerarchia dei gruppi criminali. Attraverso metodi di stampo antropologico, questo contributo intende effettuare una analisi più approfondita sui molteplici ruoli delle donne nel mercato della tratta umana. / There are not clear figures regarding the group of Nigerian women who are lured annually in the sex market in Italy. Facing such a dark number, several questions on the lives of these unknown women arise: What happens to the trafficking victims who do not find any form of social aid or assistance? What happens when the former trafficked women are not able to exit from the trade industry? According to eyewitness accounts as well as official sources, some current madams were trafficked women in the past. They made a career in the trafficking hierarchy and its organised crime groups. The female mobility towards the organisational side of the trafficking offence represents the most striking characteristic of Nigerian trade industry; that is, the victims are included by their persecutors as active part of a more complex criminal project. Such a distinctive element of Nigerian criminal model needs to be analysed through new approaches aimed at highlighting: a) the grey areas in the trade industry; b) the intermediate roles within the victim/offender model; c) the female vertical mobility in the trafficking hierarchy. Through an ethnographic methodological framework, this study wants to analyse the multiple female roles in the trafficking industry.