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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Comitê gestor da internet no Brasil (CGI.br): uma evolução do sistema de informação nacional moldada socialmente / The Brazilian Internet Steering Committee (CGI.br): A Socially Molded Evolution of the National Information System

Tomi Adachi 11 August 2011 (has links)
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.
362

Estudo do esterçamento nas quatro rodas de um veículo automotivo baseado em duas estratégias de controle da literatura / Four wheel steering study of an automotive vehicle based on two control strategies of literature

Luciana de Moraes Gamba Huttenlocher 07 December 2000 (has links)
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.
363

Telepresence and remote communication through virtual reality

Rydenfors, Gabriella January 2017 (has links)
This Master Thesis concerns a telepresence implementation which utilizes state-of-the-art virtual reality combined with live 360 degree video. Navigation interfaces for telepresence with virtual reality headsets were developed and evaluated through a user study. An evaluation of telepresence as a communication media was performed, comparing it to video communication. The result showed that telepresence was a better communication media than video communication.
364

The Swedish Rescue Service Agency’s implementation process : -A case study of SRSA: s implementation of public aid policy in international operations of 2006 / Räddningsverkets implementeringsprocess : En fallstudie om Räddningsverkets implementering av biståndsmålen i internationella insatser under 2006

Qadiri, Ali January 2008 (has links)
No description available.
365

Implementering av centralt fattade beslut i ett regionalt samverkanskomplex : en studie om implementeringen av de sociala hållbarhetsaspekterna i Kronobergs regionala tillväxtprogram

Emilsson, Kajsa January 2008 (has links)
Abstract The aim of this study is to investigate the implementation process and the implementation steering of the social development aspects, gender equality and integration, in the program for regional development of the region Kronoberg in the period of 2004-2007. The study asks three questions: 1) How have the social development aspects, gender equality and integration, been implemented in the program for regional development of the region Kronoberg? 2) What has facilitated or hindered the implementation of the two social development aspects? 3) What possibilities to steer the implementation process of the two social development aspects exist at the governmental and at the regional level? In order to answer these questions a qualitative method has been used. To be able to analyse the empirical material, which consists of documents and interviews, the theoretical framework comprehends the policy process and implementation steering. The conclusion is that the incorporation of the social development aspects in the regional development program does not fully correspond with the central intentions, and that is due to circumstances at the regional level.
366

Svensk asylpolitik : En studie kring styrning och långa handläggningstider på Migrationsverket

Fritsson, Stefan January 2009 (has links)
The Swedish Migration Board has during a long time had problems with long processing times for persons that apply for asylum. The government has set targets that investigation should not exceed 6 months although it is done in almost 70% of cases. The study's aim has been to examine if steering can be linked together to long processing times and, if so, explain why. The intention has not been to provide a comprehensive picture of the problem but has defined itself to ensure steering impact. The study has been carried out by studying relevant governing documents, previous research and by interviews with administrators and decision-makers in two of the Migration Board asylum units. The analyses of the study show that a combination of inadequate steering and inadequate resources have contributed to aggravate the implementation, which has lead to long processing times.
367

Optoelectronic modulation of mm-wave beams using a photo-injected semiconductor substrate

Gallacher, Tom F. January 2012 (has links)
This thesis discusses optoelectronic devices at mm-wave frequencies, focusing on optoelectronic beamforming and non-mechanical beam steering based on an optically excited Fresnel zone plate plasma. The optically controlled zone plate, termed the photo-injected Fresnel zone plate antenna (piFZPA) within this work, is introduced and a comprehensive theoretical framework developed. The design and optimisation of Fresnel zone plates are detailed, which determine the inherent performance of the piFZPA. A range of zone plates were designed, fabricated, and characterised at 94 GHz with up to 46 dBi gain, -26 dB sidelobe levels, and 67% aperture efficiency being measured for a quarter-wave design. The control of (sub) mm-wave beams by optical modulation of the complex permittivity of a semiconductor substrate is discussed. The significance of the free-carrier plasma dynamics, the effective lifetime, surface recombination, and the limits of the substrate which are imposed by the spatial resolution of the free-carrier plasma are highlighted, with the optimisation of these parameters discussed. The passivation quality of high-resistivity silicon wafers were characterised using a mm-wave photoconductance decay method, which yielded lifetime improvements from τ[subscript(eff)] = 60 us up to τ[subscript(eff)] ≈ 4,000 us, resulting in lowered recombination velocities (S = 15 cm/s). W-band characterisations of the passivated wafers illustrate the significance of surface recombination, with measured attenuations of up to 24 dB. Novel theoretical models are developed throughout this thesis, which yield insight into the requirements of optoelectronic devices, and are shown to agree well with measured data. The theoretical framework developed details the requirements, limitations, suitability, and design of piFZPAs at any frequency. A range of transmission-type piFZPAs are demonstrated and characterised at 94 GHz, both on-axis and off-axis, based on a novel architecture, with up to 8% aperture efficiency. Finally, the hybridisation of the piFZPA technique and well established visible display technologies, which has been developed throughout this thesis, enable low-cost, simple, and highly flexible optoelectronic devices, highlighting this method as an attractive solution to adaptive beamforming and non-mechanical steering at mm-wave and submm-wave frequencies.
368

Étude d’une matrice agile rayonnante à pixels élaborés en métamatériaux maitrise de concepts, réalisation de prototypes et caractérisation / Agile radiating matrix with elaborated metamaterial pixels. Concepts, manufacturing prototypes and caracterization

Abou Taam, Hussein 05 December 2014 (has links)
Ce mémoire est consacré à l’étude et au développement d’un nouveau système antennaire agile en rayonnement appelé MARPEM (Matrice Agile Rayonnante à Pixels Elaborés en Métamatériaux). Ce système est formé d’une matrice planaire formée par un agencement jointif de pixels électromagnétiques. Le concept du pixel est inspiré de l’antenne à Bande Interdite Electromagnétique et entouré par une enceinte murale. Ces pixels sont alimentés par des circuits de formation de faisceaux.Des études théoriques approfondies ont montré des performances électromagnétiques de MARPEM concernant le faible couplage mutuel, les forts pointages électroniques et l’élimination de lobes de réseau. Trois prototypes ont été étudiés et réalisés afin de valider expérimentalement les performances de MARPEM et de répondre aux exigences de différentes applications. / This PhD thesis is dedicated to the study and the development of a novel agile antenna system called ‘Agile Radiating Matrix with Metamaterials Pixels’. This system is formed by a planar matrix which is composed by an association of jointed electromagnetic pixels. The pixel design is inspired from the electromagnetic band gap antenna and it is surrounded by metallic walls. These pixels are fed by means of several beam forming networks.The intensive theoretical study made on the matrix antenna, showed several electromagnetic performances concerning the low mutual coupling, the great beam steering for high scanning angles and the elimination of grating lobes. Three manufactured prototypes are presented in order to experimentally validate the matrix performances and to respond to some application requirements.
369

Enabling Testing of Lateral Active Safety Functions in a Multi-rate Hardware in the Loop Environment

Björklund, Fredrik, Karlström, Elin January 2017 (has links)
As the development of vehicles moves towards shorter development time, new ways of verifying the vehicle performance is needed in order to begin the verification process at an earlier stage. A great extent of this development regards active safety, which is a collection name for systems that help both avoid accidents and minimize the effects of a collision, e.g brake assist and steering control systems. Development of these active safety functions requires extensive testing and verification in order to guarantee the performance of the functions in different situations. One way of testing these functions is to include them in a Hardware in the Loop simulation, where the involved hardware from the real vehicle are included in the simulation loop. This master thesis investigates the possibility to test lateral active safety functions in a hardware in the loop simulation environment consisting of multiple subsystems working on different frequencies. The subsystems are all dependent of the output from other subsystems, forming an algebraic loop between them. Simulation using multiple hardware and subsystems working on different frequencies introduces latency in the simulation. The effect of the latency is investigated and proposed solutions are presented. In order to enable testing of lateral active safety functions, a steering model which enables the servo motor to steer the vehicle is integrated in the simulation environment and validated.
370

Att förbereda för politiskt deltagande? : Gymnasieskolans uppdrag i samhällskunskapsundervisning / To prepare for political participation? : The mission of the upper secondary school within social studies teaching

Hagberg Ryngefors, Marielle January 2017 (has links)
The purpose of this study is to examine how upper secondary school teachers within the social studies subject interpret and transform the mission of preparing students for political participation. Based on teachers' dictums of how the mission is interpreted and transformed ahead of teaching, as well as which factors are expressed to affect this transformation, the study aims to determine what differences exist regarding how the mission is transformed and what can be seen to cause these differences. Through semi-structured interviews with seven social studies teachers, the study aims to answer three research questions addressing how the teachers interpret the mission, their expressions of how the mission is transformed ahead of teaching as well as which factors are mentioned to affect this transformation. The general conclusion of the study is that the teachers express that the mission of preparing students for political participation contain several contrasting dimensions, which in various ways are transformed ahead of teaching. The most central differences can be seen within the knowledge conveying and participation promoting dimensions, where the variations appear as the teachers to a certain extent focus on different areas of teaching and attend to these on different levels. Furthermore, different possibilities of influence and forms of participation are accentuated to various extent. To conclude, the study indicates that the teachers, qua agents of political socialisation, are preparing the students dissimilarly for political participation. / Syftet med föreliggande studie är att undersöka hur gymnasielärare i samhällskunskap tolkar och transformerar skolans uppdrag att förbereda elever för politiskt deltagande. Utifrån lärares utsagor kring hur uppdraget tolkas och transformeras inför samhällskunskapsundervisning, samt vilka faktorer som uttrycks påverka denna transformering, syftar studien till att utröna vilka skillnader som föreligger beträffande hur uppdraget transformeras, samt vad dessa skillnader kan ses bero på. Genom semistrukturerade intervjuer med sju samhällskunskapslärare, syftar studien till att besvara tre forskningsfrågor, vilka behandlar hur lärarna tolkar uppdraget att förbereda elever för politiskt deltagande, hur de uttrycker att uppdraget transformeras inför undervisning samt vilka faktorer som uttrycks påverka denna transformering. Studiens övergripande slutsats är att lärarna ger uttryck för att uppdraget att förbereda eleverna för politiskt deltagande inbegriper flera olika dimensioner, vilka transformeras på olika sätt inför undervisning. De mest centrala skillnaderna kan ses finnas inom de kunskapsförmedlande och deltagarfrämjande dimensionerna, vilket yttrar sig genom att lärarna i viss mån fokuserar på olika undervisningsområden och behandlar dessa på olika nivåer. Vidare framhävs olika påverkansmöjligheter och deltagandeformer i varierande grad. Sammanfattningsvis indikerar studien att lärarna, i egenskap av politiska socialisationsagenter, förbereder eleverna olika för politiskt deltagande.

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