Syftet med examensarbetet är att diskutera och belysa hur några skolor arbetar med attidentifiera och stötta elever med dyslexi och sätta det i relation till skolans styrdokument. Föratt kunna undersöka dessa frågeställningar användes semistrukturerade intervjuer med sexstycken lärare som alla arbetar på olika skolor. Resultaten visar att skolorna arbetar med attkartlägga och följa upp eleverna och att lärarna försöker kompensera elevers svårighetergenom olika pedagogiska stöd och tekniska hjälpmedel. Skolorna arbetar inkluderande och deanpassar undervisningen och lärandemiljön utifrån elevernas olika behov och svårigheter.Resultaten visar också det finns dilemman som lärarna mött under sitt arbete med att hjälpaeleverna med dyslexi så som att skolan ska vara kompensatorisk men samtidigt varainkluderande, tidsbrist, hjälpmedlen kan vara utpekande och att eleverna behöver få endiagnos för att skolan ska få extra resurser. / The aim of the study is to discuss and illustrate how some schools are working to identify andsupport pupils with dyslexia and how it relates to their policy documents. To investigate thesequestions, semi-structured interviews were chosen as the method. Six teachers, all working atdifferent schools, were interviewed. The results show that the school are working to identifyand follow up students, and that educators are trying to compensate for pupils difficultiesthrough a variety of educational supports and assistive technology. Schools working in aninclusive and personalizing the teaching and learning environment according to puppilsdifferent needs and difficulties. The results also show there are dilemmas that educators facedin their effort to help students whit dyslexia as that the school should be compensatory but atthe same time inclusive, lack of time, that the us of aids can become stigmatizing, andstudents need a diagnosis for the school to get extra resources.

This thesis examines digital inclusion and how it is governed in today’s politics. The main focus is on the region of Östergötland, the municipality of Norrköping and a project called Digital media bus in Östergötland. To give the reader some understanding about digital inclusion the thesis starts with earlier research on digital inclusion, the role of the library in solving this problem about digital divides and how it has been governed before. Then, some background information about Europe and Swedens digital development, their digital agendas, current legislation in Sweden about digital inclusion and two campaign weeks which aim to increase the digital inclusion in Europe and Sweden. The theoretical framework is based on a theory about different policy instruments and from a governance perspective. The theoretical framework interacts with the empirical material in the analysis. The empirical material is based on interviews with two politicians and three public officials, on different regulatory documents and on the project Digital media bus in Östergötland which has been observed during the year of 2016. The empirical material is presented in the sixth chapter called ”There are needs, so there must be solutions!”. The result is that digital inclusion is a policy which is hard to govern. Today, it seems like there is mostly soft policy instruments and the way to govern is from a governance perspective – which means that there are a lot of networks and dissemination of information. However, a harder way to govern is requested by the informants because it may release necessary resources to solve the problem with digital exclusion. The project Digital media bus in Östergötland used mostly soft policy instruments in their work with getting children more technical skilled and digital curious. The main outcome from the project is that the problem with digital inclusion has got more attention both in the politics and the official administration, but the project has also shown the importance of cooperation. Lastly in my thesis, I discuss my results and propose some further research about digital inclusion.

The objectives of this work were to investigate, design and implement beam steering antenna arrays for mobile and wireless applications using the genetic algorithm (GA) and particle swarm optimisation (PSO) techniques as optimisation design tools. Several antenna designs were implemented and tested: initially, a printed dipole antenna integrated with a duplex RF switch used for mobile base station antenna beam steering was investigated. A coplanar waveguide (CPW) to coplanar strip (CPS) transition was adopted to feed the printed dipole. A novel RF switch circuit, used to control the RF signal fed to the dipole antenna and placed directly before it, was proposed. The measured performance of the RF switch was tested and the results confirmed its viability. Then two hybrid coupled PIN diode phase shifters, using Branchline and Rat-Race ring coupler structures, were designed and tested. The generation of four distinct phase shifts was implemented and studied. The variations of the scattering parameters were found to be realistic, with an acceptable ±2 phase shift tolerance. Next, antenna beam steering was achieved by implementing RF switches with ON or OFF mode functions to excite the radiating elements of the antenna array. The switching control process was implemented using a genetic algorithm (GA) method, subject to scalar and binary genes. Anti-phase feeding of radiating elements was also investigated. A ring antenna array with reflectors was modelled and analysed. An antenna of this type for mobile base stations was designed and simulation results are presented. Following this, a novel concept for simple beam steering using a uniform antenna array operated at 2.4 GHz was designed using GA. The antenna is fed by a single RF input source and the steering elements are reactively tuned by varactor diodes in series with small inductors. The beam-control procedure was derived through the use of a genetic algorithm based on adjusting the required reactance values to obtain the optimum solution as indicated by the cost function. The GA was also initially used as an optimisation tool to derive the antenna design from its specification. Finally, reactive loading and time modulated switching techniques are applied to steer the beam of a circular uniformly spaced antenna array having a source element at its centre. Genetic algorithm (GA) and particle swarm optimisation (PSO) processes calculate the optimal values of reactances loading the parasitic elements, for which the gain can be optimised in a desired direction. For time modulated switching, GA and PSO also determine the optimal on and off times of the parasitic elements for which the difference in currents induced optimises the gain and steering of the beam in a desired direction. These methods were demonstrated by investigating a vertically polarised antenna configuration. A prototype antenna was constructed and experimental results compared with the simulations. Results showed that near optimal solutions for gain optimisation, sidelobe level reduction and beam steering are achievable by utilising these methods. In addition, a simple switching process is employed to steer the beam of a horizontally polarised circular antenna array. A time modulated switching process is applied through Genetic Algorithm optimisation. Several model examples illustrate the radiation beams and the switching time process of each element in the array.

Thesis with the title "Life stories and professional careers of women headmasters of vocational high schools" deals with professional life of women headmasters of vocational high schools and analyzes this professional life. Per this analysis is detected, what is the benefit of these headmasters for school and if they promote a development of the school. Narrative analysis was used on this research.Beside the research there are answered other questions, which are related to professional life and are associated with the primary research question. There are described the phases of professional life and there are stated the effects, which influence the decision making of the headmasters. In the conclusion of research the headmasters alone evaluate their actions in position of headmaster.The primary research question is answered, how it results from research, all headmasters are benefit for their school. Schools, which were guided by them, had evolved and it is them, who are the reason of its growth. Recommendations for futher research is analysis of professional men headmasters.

Denna rapport omfattar konstruktionen av ett fristående drivkort med tillhörande mobilapplikation för styrning och konfiguration av ett hydraulsystem. Projektets syfte var att på beställaren Bosch Rexroth ABs begäran undersöka om pump control module (PCM) - en del ur det existerande Spider 3 styrsystemet - kunde användas som en fristående modul. Hårdvara med en Bluetoothmodul skapades och kopplades mot PCM för att möjliggöra kommunikation via Bluetooth. En mobilapplikation utvecklades i Android studio för att tillåta konfiguration från en mobil enhet. Mjukvaran i PCM modifierades för att kommunicera med Bluetooth-hårdvaran över CAN och även för att tillåta analog styrning av pumpen via en strömstyrd ingång. De grundläggande kraven för systemet uppfylldes och en fungerande prototyp kunde uppvisas vid projektets slut. Prototypen visade stor potential men saknade dock viss funktionalitet som vore önskvärd hos en kommersiell produkt. / This report encompasses the development of a standalone drive card with an accompanying mobile application for control and configuration of a hydraulic system. The purpose of the project was to - according to an inquiry from the client Bosch Rexroth - investigate whether the pump control module (PCM) from the existing Spider 3 control system could be used as a standalone module. Hardware including a Bluetooth module was assembled and connected to the PCM to allow communication over Bluetooth Low Energy (BLE). A mobile application where developed in Android Studio to allow configuration from a mobile device. The software of the PCM were modified to communicate with the Bluetooth hardware over CAN and also for allowing analog control of the hydraulic pump through a current controlled input.The basic demands for the system were met and a working prototype could be demonstrated at the end of the project. The prototype did show large potential but was lacking some functionality which would be desirable for a commercial product.

Cette thèse permet de porter l'attention à quelques caractéristiques fondamentales de l'école catholique et de chercher dans quelle mesure sa navigation professionnelle permettrait de tirer la garantie de sa capacité de rénover le système de gestion et de mesure des performances, entre son pilotage des compétences et son renforcement stratégique de la qualité. Dans l'histoire de l'école catholique, plusieurs chercheurs ont présenté l'importance des défis qui l'interpellent et qui l'invitent à trouver des réponses adaptées non seulement au niveau des contenus des méthodes didactiques (choix de la pédagogie adaptée aux besoins des élèves) mais aussi au niveau du travail administratif. Dans la recherche, nous avons donc pris en considération ces réalités qui incitent l'école catholique d'une part à faire une adaptation de ses structures et de son mode d'agir, pour continuer à être une présence efficace et incisive dans le secteur éducatif tout en vivant sa vocation, et d'autre part. à mesurer sa performance globale et piloter ses décisions de façon professionnelle. Dans ce sens, nous avons innové « MAR_BEL S.M.D » (un système de gestion et de mesure de la performance globale d'une école catholique) pour proposer des structures de modélisation d'une école apprenante, qualifiante et en quête de professionnalisation d'une part, et d'autre part pour améliorer ses décisions stratégiques. En effet, ce système de modélisation et de décisions a permis à travers une enquête de vérifier les liens entre des concepts théoriques et des réalités professionnelles vécues dans un contexte complexe sur le territoire libanais. / This thesis makes it possible to pay the attention to some fundamental characteristics of the Catholic school and up to what point to seek its professional navigation would allow drawing the guarantee from its capacity to renovate the system of management and measurement of the performances, between its piloting of competences and its strategic reinforcement of quality. In the history of the Catholic school, several researchers had the importance of the challenges which defy it and which invite it to find answers adapted not only to the level of the contents of the didactic methods (choice of the pedagogy adapted the needs of the pupils) but also to the level of administrative work. In research, we thus took into account these realities which encourage the Catholic school on the one hand to make an adaptation of its structures and its mode to act, to continue to be an effective presence and incisor in the educational sector while living its vocation, and on the other hand, to measure its total performance and to control its decisions in a professional way. ln this direction, we innovated "MAR_BEL S.M.D" (system of management and measurement of the total performance of a Catholic school) to propose structures for the modeling of a learning school, qualifying and in search of professionalisation on the one hand, and on the other hand to improve its strategic decisions. lndeed, this system of modeling and decisions made it possible through an investigation to check the bonds between theoretical concepts and the professional realities lived in a complex context into the Lebanese territory .

Dans cette thèse, on s'est attaché à résoudre un certain nombre de problèmes qui apparaissent lorsqu'on traite des problèmes concrets de contrôle: phénomènes à plusieurs échelles de temps, discontinuités de la commande lors du basculement d'un correcteur à un autre, nécessité de concevoir un nombre limité de correcteurs différents malgré une gamme très importante des produits traités. Pour illustrer concrètement les résultats obtenus, nous nous sommes appuyés sur un exemple industriel concret, le contrôle de guidage de bande durant le processus de laminage dans un laminoir à chaud. D'abord, nous proposons une solution convexe au problème de commande optimale linéaire quadratique pour les systèmes linéaires à deux échelles de temps en temps discret. Ensuite, nous établissons des conditions suffisantes, formulées sous la forme d'inégalités matricielles linéaires, qui permettent de vérifier la stabilité d'un système à commutation à deux échelles de temps et de synthétiser des correcteurs stabilisants. Nous proposons aussi dans ce travail une méthode pour minimiser les discontinuités sur la commande dans le cadre des systèmes à commutation. Dans le contexte du contrôle de guidage de bande pour un laminoir à chaud, nous ne pouvons pas négliger l'influence des paramètres incertains, qui sont dus principalement au fait que ce genre de système traite une gamme de produits très large. Donc, dans la synthèse du correcteur, nous prenons en compte ces variations en divisant l'ensemble des produits en plusieurs familles et en synthétisant un correcteur différent pour chaque famille / This Ph.D. thesis deals with a certain number of problems arising in practical implementation of control systems: multi time scale phenomena, sudden modifications on the system dynamics, discontinuities on the control signal due to controller switchings, the need of design a limited number of controllers in spite of a wide variation on the physical parameters. In order to illustrate the validity of the obtained results, we resort to a real problem concerning the steel production framework, the robust steering control of a hot strip finishing mill. First, a convex solution of the linear quadratic control design for discrete two time scale systems is proposed. Hence, we address the stability problem of two time scale switched systems. We show that stability of the slow and fast switched subsystems under arbitrary switching rules does not imply the stability of the corresponding two time scale switched system in the singular perturbation form. An additional constraint, independent of the value of the singular parameter and of the switching rule, is provided in terms of linear matrix inequalities. We also introduce a bumpless transfer method for switched systems aiming at reducing the discontinuities on the control signal. Dwell time conditions assessing the asymptotic stability of the closed loop switched system are established. The practical contribution of this thesis, the robust steering control design, exploits most of previous results. The objective is to guarantee the stability of the hot strip mill system and improve the quality of the rolled products

De nos jours, les antennes à réseaux transmetteurs attirent un grand intérêt pour de nombreuses applications civiles et militaires aux bandes de fréquence comprises entre 10 et 110 GHz (réseaux de communication 5G, liens point à point, radars, etc.).Le travail de thèse vise à faire des innovations dans la modélisation et la conception d'antennes à réseaux transmetteurs pour des applications en bande Ka (28-40 GHz). Il porte plus précisément sur le développement d'outils numériques pour l’analyse théorique des réseaux transmetteurs, la conception et la démonstration de plusieurs prototypes avec des fonctionnalités avancées, telles que des réseaux transmetteurs passifs (larges bandes ou à multifaisceaux) et actifs (à reconfiguration électronique).La première partie des travaux consiste en une analyse théorique des réseaux transmetteurs. Dans un premier temps, l’impact de la méthode de compensation de phase sur les performances des réseaux transmetteurs est étudié. La loi de compensation de phase de l’onde quasi-sphérique incidente sur l’ouverture du réseau transmetteur est calculée en utilisant deux méthodes nommées compensation à phase constante et compensation par ligne à retard, et nous montrons que cette dernière permet d’augmenter la bande passante du réseau transmetteur et de corriger les erreurs de dépointage du faisceau. Dans un second temps, le principe de fonctionnement des réseaux transmetteurs facettés est décrit en détail. La simulation numérique du réseau transmetteur à trois facettes est validée au travers de simulations électromagnétiques 3-D. Pour un certain angle d’inclinaison, nous montrons que la bande passante et la capacité de dépointage du réseau transmetteur sont améliorées au détriment du gain.La suite des travaux porte sur la conception et le prototypage de deux réseaux transmetteurs passifs, dont l’un à faisceau collimaté et très large bande et l’autre à quatre faisceaux fixes. Les deux réseaux transmetteurs sont basés sur une cellule élémentaire à 3bits qui assure une double fonction à savoir la compensation de phase et la conversion de la polarisation linéaire en circulaire. Le réseau passif à faisceau collimaté présente un gain mesuré de 33,8 dBi (correspondant à une efficacité d'ouverture de 51,2%) et une bande passante à -3 dB supérieure à 15,9%. La distribution de phase du réseau transmetteur à quatre faisceaux a été optimisée par un algorithme génétique afin d’avoir des faisceaux dépointés à ± 25° dans le plan horizontal et le plan vertical à la fréquence d’optimisation.La dernière partie des travaux vise la conception d’un réseau transmetteur reconfigurable à 27-31 GHz. Dans un premier temps, une cellule élémentaire active à quatre états de phase (2 bits) en polarisation linéaire a été conçue et validée expérimentalement. Elle est composée de six couches métalliques imprimées sur trois substrats. Les éléments rayonnants sont des antennes patch rectangulaires comprenant chacun deux diodes PIN pour contrôler la phase de transmission. Le principe de fonctionnement de la cellule élémentaire a été validé expérimentalement avec des pertes d’insertion minimales de 1.6-2,1 dB et une bande passante en transmission (à 3 dB) de 10-12,1% pour les quatre états de phase 0 °, 90°, 180° et 270°. Cette cellule a ensuite été utilisée pour la conception d’un réseau transmetteur reconfigurable comprenant 14 × 14 cellules unitaires et 784 diodes PIN. Un prototype a été réalisé et caractérisé, il présente un gain maximum mesuré de 19,8 dBi, correspondant à une efficacité d'ouverture de 23,5%, et une bande passante à 3 dB de 4,7 GHz (26,2-30,9 GHz). Malgré quelques éléments défaillants, ce prototype valide le principe de fonctionnement et la faisabilité de réseaux transmetteurs en bande Ka avec une quantification de phase de 2 bits et constitue une des premières réalisations de ce type dans l’état de l’art actuel. / Nowadays, transmitarray antennas are of great interest for many civil and military applications in frequency bands between 10 and 110 GHz (5G mobile networks, point-to-point communication systems, radars, etc.).This thesis aims to make major innovations in modeling and design of transmitarray antennas for Ka-band applications (28-40 GHz). It focuses on the development of numerical tools, and the design and demonstration of several prototypes with advanced functionalities, such as passive (broadband or multibeam) and active (at electronic reconfiguration) transmitarrays.The first part of the work consists of a theoretical analysis of the transmitarray antenna. In a first step, the impact of the phase compensation method on the performance of the transmitarray is studied. The phase compensation law of the quasi-spherical wave incident on the array aperture is calculated using two methods called constant phase compensation and true-time delay (TTD) compensation. The numerical results show that TTD compensation allows an increase of the transmitarrays bandwidth and a reduction of the beam squint as compared to constant phase-shift compensation. In a second step, the operating principle of facetted transmitarrays is described in detail. The numerical simulation of a 3-facet transmitarray is validated through 3-D electromagnetic simulations. For a certain facet angle, the bandwidth and the beam scanning capability of the TA are improved at the expense of the gain.The next step of the work concerns the design and prototyping of two passive transmitarray antennas, one with a collimated and a large bandwidth, and the other with four fixed beams. The two transmitarrays are based on a 3-bit unit-cell providing two functions, namely the phase compensation and the polarization conversion from linear to circular. The passive beam-collimated transmitarray exhibits a measured gain of 33.8 dBi (corresponding to an aperture efficiency of 51.2%) and a 3-dB gain-bandwidth larger than 15.9%. The quad-beam transmitarray phase distribution has been optimized by a genetic algorithm code coupled with an analytical tool. The array is designed to radiate four beams at ±25° in the horizontal and vertical planes at the optimization frequency.The last part of the work aims to the design of a 27-31 GHz reconfigurable transmitarray antenna. Initially, an active unit-cell with four phase states (2 bits) in linear polarization was designed and validated experimentally. It consists of six metal layers printed on three substrates. The radiating elements are rectangular patch antennas, each of them including two PIN diodes to control the transmission phase. The operating principle of the unit-cell has been experimentally validated with a minimum insertion loss of 1.6-2.1 dB and a 3-dB transmission bandwidth of 10-12.1% for the four phase states. 0°, 90°, 180° and 270°.Then, this unit-cell was used for the design of a reconfigurable transmitarray antenna comprising 14 × 14 unit cells and 784 PIN diodes. A prototype was realized and characterized, it presents a measured maximum gain of 19.8 dBi, corresponding to an aperture efficiency of 23.5%, and a 3-dB bandwidth of 4.7 GHz (26.2% at 30.9 GHz). Despite some faulty elements, this prototype validates the operating principle and the feasibility of Ka-band transmitarray antennas with a 2-bit phase quantization. It is one of the first demonstration of such an antenna in the current state of the art.

A Internet é um fenômeno importante para o desenvolvimento da sociedade da informação em diversos aspectos: social, econômico, cultural e político, além de suas dimensões técnicas e de infraestrutura de Tecnologia da Informação e Comunicação. Este estudo se propõe a somar ao arcabouço de conhecimento da Internet, por meio da análise dos atores, agentes e estruturas que construíram a rede que suporta a governança da Internet nacional, indicando a importância do seu papel na evolução do Sistema de Informação e Comunicação brasileiro. Para tanto, utiliza o estudo de caso do Comitê Gestor da Internet no Brasil (CGI.br) como base para a narrativa elaborada com os critérios das teorias Ator-Rede, de Latour, Law e Callon e Estruturação, de Giddens, inserida em um contexto panorâmico, baseada no contextualismo de Pettigrew, auxiliando a compreensão de alguns fatos e eventos no tempo e espaço. A teoria Ator-Rede propicia elementos conceituais para se construir a rede que articulou a criação da infraestrutura da Internet, da sua fase acadêmica até culminar na criação do Comitê Gestor, permitindo a inserção de atores não humanos, como os backbones acadêmicos. A Teoria da Estruturação é utilizada para demonstrar a dualidade da rotina de interação entre os membros do Comitê Gestor e os recursos e políticas públicas do Sistema de Informação e Comunicação nacional, bem como sua recursividade, ao longo da governança da Internet. Pettigrew sugere compor o contexto interno e externo do caso, de forma longitudinal e vertical, do processo de construção da Internet nacional, da fase acadêmica à institucionalização da governança, resultando em um desenvolvimento fluido, em âmbito nacional e internacional. A questão de investigação que norteou este estudo é qual a dimensão do CGI.br no desenvolvimento da governança da internet no Brasil e o seu efeito no desenvolvimento e uso da Internet no país. Secundariamente se investigou: como foi construída a rede do CGI.br, como ela evoluiu e se sustentou, ao longo de sua história; e como o GCGI.br se articulou com as organizações nacionais e internacionais. O estudo de caso único adota uma perspectiva sociológica de Sistema de Informação, epistemologicamente fundamentada no construtivismo, com uma abordagem interpretativista. Baseado em entrevistas com pessoas diretamente ligadas à história do CGI.br, os dados foram triangulados com informações secundárias, coletadas em documentos oficiais e acadêmicos. A Internet no Brasil tem quatro marcos importantes: primeiro, a criação da infraestrutura na fase do backbone acadêmico; segundo, a portaria interministerial que cria o CGI.br; terceiro, a transição da Era FHC para o governo Lula, que assina o decreto que atribui ao Comitê a definição de diretrizes estratégicas, e quarto, o processo de convergência digital em curso, no mundo inteiro. A governança multi-stakeholder é um dos fatores que torna a Internet brasileira um sucesso, todavia, ela floresceu na fase em que a Lei da Informática estava sendo flexibilizada e o Sistema de Telecomunicação nacional, em fase de privatização. Portanto, se percebe uma simbiose entre o desenvolvimento da Internet e a evolução da sociedade da informação doméstica, e uma relação de mútua vantagem entre a governança liderada pelo CGI.br e os movimentos de abertura do mercado de Tecnologia da Informação e Comunicação*. / Internet is an important phenomenon for the development of information society in many aspects: social, economic, cultural and political apart of its Information and Communication Technology dimension. This study aims to add up some knowledge on the existing Internet studies, through the analysis of actors, agents and structures who have built the network which supports the national Internet governance, drawing the importance of their roles on the evolution of the Brazilian Information and Communication System. The case study utilised is the Brazilian Internet Steering Committee (CGI.br), narrated and analysed through Latour, Callon and Law academic studies about actor-network theory, and Giddens\'s theory of Structuration, inserted in a panoramic context, based on Pettigrew\'s contextualism in order to support the understanding of certain facts and events in time and space. Actor-Network theory provides conceptual elements to bring up the facts and events from its academic stage, which ended up with the development of Internet infrastructure and later on the creation of the Steering Committee. This theory allowed the inclusion of non-human actors such as academic backbones. The Structuration Theory is used to demonstrate the duality between members of the Steering Committee and the resources and policies of Brazilian Information and Communication System, and its recursiveness over the Internet governance. Pettigrew suggests encompass the internal and external context of the case, using a longitudinal and vertical analyse of Brazilian Internet development process, from the academic phase to the institutionalization of its governance, which evolution flowed fluidly, within the country and in international environment as well. This study was driven by the research question: what is the dimension of CGI.br in regard to the development of Brazilian Internet governance and its effects on the development and use of the Internet within the country. Secondly was investigated: how the CGI.br network was built, how it evolved and sustained over its history; and how CGI.br articulated within the national and international organizations. The single case study adopts a sociological perspective of the Information System, epistemologically grounded in constructivism, with an interpretative approach. Based on interviews with people directly linked to the history of CGI.br, data were triangulated with secondary information, collected from official documents and academic works. Brazilian Internet has four milestones: first, the development of infrastructure in the academic backbone period; second, the ministerial ordinance establishing the CGI.br; third, was the transition from FHC to Lula, who amended the ordinance with a Presidential decree that empowered the committee to define the strategic guideline for national Internet development; and fourth, the process of digital convergence in progress worldwide. The multi-stakeholder governance is one factor that makes the Internet a success, bearing in mind that Internet has evolved and flourished during the ICT relaxation. Therefore, we can see a symbiosis between the Internet development and evolution of Brazilian information society, and a mutual relationship between CGI.br Internet governance and the Information and Communication Technology liberalization movements.

O comportamento da dinâmica lateral de veículos automotivos com esterçamento nas quatro rodas é estudado com o auxílio de uma ferramenta computacional de modelagem e simulação de sistemas multicorpos. São utilizadas duas estratégias de controle do esterçamento das rodas traseiras para a avaliação de suas principais características. Uma das estratégias esterça as rodas traseiras em função do ângulo de esterçamento do volante, e a outra esterça as rodas traseiras em função do ângulo de esterçamento do volante e da velocidade longitudinal do veículo. O teste utilizado para as análises é a entrada degrau de esterçamento, onde é avaliada a resposta transitória e de regime da aceleração lateral, da velocidade de guinada e do ângulo de rolagem dos veículos. Os resultados das simulações mostram que os veículos com esterçamento nas quatro rodas têm o tempo de resposta da velocidade de guinada maior, e da aceleração lateral e do ângulo de rolagem menores que o veículo convencional. Também apresentam uma diminuição no ganho da aceleração lateral, da velocidade de guinada e do ângulo de rolagem. Além disso apresentam uma característica subesterçante mais acentuada. Essas características são mais evidentes no veículo com estratégia de controle função do esterçamento do volante. Os resultados obtidos correspondem ao comportamento dos veículos com esterçamento nas quatro rodas apresentado na literatura. / The lateral dynamic behavior of the automotive vehicles is studied with the aid of a computational tool for multibody systems modeling and simulation. Two rear wheel steering control strategies are used for evaluation of the main four wheel steering characteristics. One strategy steer the rear wheels as a function of the steering wheel angle, and the other one, steer the rear wheels as a function of the steering wheel angle and the speed. The steer step input is the test used, where the lateral acceleration, the yaw rate and the roll angle transient and stead state response are evaluated. The simulation results show that the four wheel steering vehicles have a slower yaw rate time response, and a fast lateral acceleration and roll angle time response than the conventional vehicle. Also four wheel vehicles show a reduction in lateral acceleration, yaw rate a.nd roll angle gain. Moreover they are more understeer than the conventional vehicle. These characteristics are particularly more evident on the vehicle with steer dependent system. The obtained results correspond with four wheel steering vehicles behavior founded in literature.