Made available in DSpace on 2014-06-12T18:35:26Z (GMT). No. of bitstreams: 2 arquivo7462_1.pdf: 14072795 bytes, checksum: 231b1ecadddace6a9f1e3f5f44122905 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2007 / Há hoje em curso uma substancial mudança tanto do ponto de vista cultural quanto tecnológico a partir da adoção, por parte da sociedade, de novos paradigmas éticos e morais os quais proporcionaram a instauração de uma relação de vida pautada na velocidade, eficácia e produtividade. Essas alterações também repercutiram na linguagem, sobretudo com o advento da Internet, e colaboraram para modificar as relações de leitura e escrita. A Charge Virtual, através da Análise Crítica do Discurso e da análise multimodal, é um gênero ideal para investigar a construção de identidades sociais. Esta pesquisa tem por finalidade analisar as Charges Virtuais, especificamente do autor Maurício Ricardo exibidas no site www.charges.com.br e observar como os diversos modos de organização (animação, texto-verbal, áudio e imagem) interagem e formam a significação do gênero em análise. Além disso, este estudo procura investigar, tendo como base a Análise Crítica do Discurso e a análise multimodal, de que maneira as relações lingüístico-discursivas constituem uma base para a construção de identidades por meio de discursos estereotipados presentes nas falas das personagens da charge

Made available in DSpace on 2014-06-12T23:00:13Z (GMT). No. of bitstreams: 2 arquivo9130_1.pdf: 1428164 bytes, checksum: 73f1cb334dd746a4945ee290cfff3f6f (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2004 / O objetivo deste trabalho é explicar a construção do espaço virtual na Internet, especificamente em ambientes de chat, a partir de uma abordagem sócio-cultural da psicologia. Através desta abordagem, o espaço virtual foi visto como um espaço relacional em contínua transformação, no qual as pessoas se localizam e localizam as outras em um ambiente computacional. Os ambientes tratados neste estudo são os chats, definidos como recursos da Internet que possibilitam comunicação síncrona entre indivíduos. A partir de releituras do enfoque sócio-cultural, do materialismo dialético e de estudos lingüísticos, bem como da prática de utilização de chats, foi construída uma unidade de análise denominada intercal(ação) de marcadores espaço-virtuais. Esta unidade de análise envolve elementos de localização (basicamente aqueles com uma função dêitica) e seqüências interacionais (em termos de mensagens que possibilitam a construção do espaço), além de estar associada às transformações de expectativas e pressuposições dos participantes do chat. Foram analisados chats com atividades previamente definidas (encontros acadêmicos realizados no contexto da plataforma Virtus, entrevistas on-line e serviços de suporte realizados no Website da UOL) e chats sem uma atividade previamente definida (bate-papos nos sistemas Terra, mIRC, Paltalk e Yahoo Messenger). A análise definiu sete categorias relacionadas às estratégias psicológicas de construção do espaço virtual pelos usuários dos sistemas (conexão, engajamento, emergência, manutenção, imergência, desengajamento e desconexão). Algumas conclusões da análise são: as estratégias psicológicas dos usuários tornaram possível que eles entrassem, permanecessem e saíssem do espaço virtual por meio de elementos dêiticos relacionados aos movimentos virtual-físico e virtual-virtual; os elementos dêiticos têm funções próprias em cada categoria e chats com atividades previamente definidas e sem atividades previamente definidas determinam a construção do espaço virtual bem como o tipo de atividade. Outras contribuições deste trabalho, além da análise de construção do espaço virtual, são as investigações teóricas para o estudo da abordagem sócio-cultural com base em fundamentos do materialismo dialético, o entendimento de como ambientes específicos como aqueles com atividades educacionais têm seu próprio espaço e a compreensão da interface de ambientes computacionais em uso através da observação do processo de construção do espaço virtual

In many instances of virtual machine deployments today, virtual machine instances are created to support a single application. Traditional operating systems provide an extensive framework for protecting one process from another. In such deployments, this protection layer becomes an additional source of overhead as isolation between services is provided at an operating system level and each instance of an operating system supports only one service. This makes the operating system the equivalent of a process from the traditional operating system perspective. Isolation between these operating systems and indirectly the services they support, is ensured by the virtual machine monitor in these deployments. In these scenarios the process protection provided by the operating system becomes redundant and a source of additional overhead. We propose a new model for these scenarios with operating systems that bypass this redundant protection offered by the traditional operating systems. We prototyped such an operating system by executing parts of the operating system in the same protection ring as user applications. This gives processes more power and access to kernel memory bypassing the need to copy data from user to kernel and vice versa as is required when the traditional ring protection layer is enforced. This allows us to save the system call trap overhead and allows application program mers to directly call kernel functions exposing the rich kernel library. This does not compromise security on the other virtual machines running on the same physical machine, as they are protected by the VMM. We illustrate the design and implementation of such a system with the Xen hypervisor and the XenoLinux kernel. / Science, Faculty of / Computer Science, Department of / Graduate

M.Comm. / The discipline of management, denoting the concepts of management and leadership, has been deliberated in boundless number of books, magazines and journals over the years. Some views are that there is a distinction between management and leaders, whilst others vehemently argue that there is no difference between the two terms, and use them synonymously. Leadership is the nucleus of all organisations. Moreover, sustained performance, competitive advantage and success, depends both on effective leadership, as well as committed followers.The literature study undertaken discovered writings confirming the distinctions between the terms groups and teams: groups may fall inside or outside the boundaries of an organisation, such as social groups, whereas teams (in their various forms) are generally referred to in the context of "working teams" in an organisation. Teams may be formed from groups, subsequent to their maturity. In many instances, the usage of the terms "groups" and "teams", are also used interchangeably.

The research centres on the theme that, even though there are various drivers for a more virtual workplace, ranging from organisational, workforce and technology to environmental issues, it seems that progress in adopting virtual work on both individual and organisational level, is still low. The purpose of the research is to determine if there are specific mindsets required to make the implementation of a virtual workplace more successful, with the aim of making recommendations to organisations, managers, teams and individuals for improved implementation strategies. The research defined the target population as a large South African Information and Communication Technology (ICT) company, and its customers. A combination of quantitative and qualitative methods was used. Data relating to needs, perceptions, practicality and readiness concerning the virtual workplace was collected on three levels, namely individual, team and organisational level. The quantitative research covered the objectives relating to the individual level through questionnaires which were sent out in the form of online surveys. The qualitative research covered the organisational level research through individual interviews with the IT/HR managers, while the team level research was covered through focus group interviews. The study found that various mindsets and needs do exist, and on an individual level the mindsets and needs are not restricted to specific generations. This could be of significance to HR and IT managers in general, who may need to take a wider target group into consideration when designing policies and standards for the organisation. Secondly the organisation itself emerged as an entity with a mindset or culture that transcends the individuals working for the organisation. To implement a virtual workplace would, therefore, require an overarching strategy and organisational change interventions to ensure that all the facets of a virtual workplace are addressed in a balanced way. / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted

Most Virtual Reality systems employ some form of parallel processing, making use of multiple processors which are often distributed over large areas geographically, and which communicate via various forms of message passing. The approaches to parallel decomposition differ for each system, as do the performance implications of each approach. Previous comparisons have only identified and categorized the different approaches. None have examined the performance issues involved in the different parallel decompositions. Performance measurement for a Virtual Reality system differs from that of other parallel systems in that some measure of the delays involved with the interaction of the separate components is required, in addition to the measure of the throughput of the system. Existing performance analysis approaches are typically not well suited to providing both these measures. This thesis describes the development of a performance analysis technique that is able to provide measures of both interaction latency and cycle time for a model of a Virtual Reality system. This technique allows performance measures to be generated as symbolic expressions describing the relationships between the delays in the model. It automatically generates constraint regions, specifying the values of the system parameters for which performance characteristics change. The performance analysis technique shows strong agreement with values measured from implementation of three common decomposition strategies on two message passing architectures. The technique is successfully applied to a range of parallel decomposition strategies found in Parallel and Distributed Virtual Reality systems. For each system, the primary decomposition techniques are isolated and analysed to determine their performance characteristics. This analysis allows a comparison of the various decomposition techniques, and in many cases reveals trends in their behaviour that would have gone unnoticed with alternative analysis techniques. The work described in this thesis supports the Performance Analysis and Comparison of Parallel and Distributed Virtual Reality systems. In addition it acts as a reference, describing the performance characteristics of decomposition strategies used in Virtual Reality systems.

In recent years, the problem of automating the formation of Virtual Organisations (VO) has risen to prominence. Work in this area has typically considered the process of VO formation to be a centralised process driven by a company with responsibility for the business opportunity.Such systems use two main stages: first they decompose the business opportunity into a set of roles and then select suppliers for each role by matching their advertised capability against criteria supplied by the user. Both stages require that the company driving the VO formation process has access to considerable amounts of centralised knowledge.In contrast, this thesis considers virtual organisations as forming by combining the cooperative contributions within a group of organisations. It is shown that, within this context, both the knowledge required to facilitate and the control within the virtual organisation formation process are naturally distributed. In particular companies are free to vary their level of commitment to given projects and so only they have detailed knowledge of their capabilities. Supporting VO formation within this context requires a novel approach capable of utilising this distributed information. The primary contribution of this thesis is to provide such a novel approach to supporting virtual organisation formation. This approach builds on the traditions of blackboard and multi-agent systems. It allows virtual organisation formation to be driven by the accumulation of voluntary contributions from the prospective members of the virtual organisation. The principle focus of the system is on identifying candidate virtual organisations, and it does not offer automated support for such aspects as the creation of contracts. Crucially this system works with the distributed knowledge encountered in the chosen problem domain. The following technical contributions shape the general approach into a detailed system: (a) the representation of company's capabilities, (b) an algorithm for combining those capabilities and (c) mechanisms enabling intelligent agents representing the companies to produce candidate virtual organisations. The proposed system is evaluated in three ways - its technical feasibility is demonstrated through the implementation of a testbed prototype, a theoretical discussion of the systems performance is given and finally its potential benefits are shown in a reasoned case study.

The current infrastructure as a service (IaaS) cloud systems, allow users to load their own virtual machines. However, most of these systems do not provide users with an automatic mechanism to load a network topology of virtual machines. In order to specify and implement the network topology, we use software switches and routers as network elements. Before running a group of virtual machines, the user needs to set up the system once to specify a network topology of virtual machines. Then, given the user’s request for running a specific topology, our system loads the appropriate virtual machines (VMs) and also runs separated VMs as software switches and routers. Furthermore, we have developed a manager that handles physical hardware failure situations. This system has been designed in order to allow users to use the system without knowing all the internal technical details.

Virtual Reality is currently an affordable and consumer ready technology used by many in the games and interactive media industry, however unlike the user interface standards in mobile, PCs, and Macs, VR UI design can vary in complexity and usability. VR has many times been linked in films, TV shows, and animation as a method for navigating through cyberspace. It has been portrayed to be involved in the process of hacking a computer on some network. This study will look at approaches to developing a UI system using cyber-security research applications as a basis for designing a framework. Throughout, this research will analyze the different approaches to UI design and data visualization, extract relevant information, and find out what approaches will help improve the VR software front end design.

Espectáculo circense virtual de la compañía MDF