902 resultados para Modern and contemporany architecture
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In this chapter we described how the inclusion of a model of a human arm, combined with the measurement of its neural input and a predictor, can provide to a previously proposed teleoperator design robustness under time delay. Our trials gave clear indications of the superiority of the NPT scheme over traditional as well as the modified Yokokohji and Yoshikawa architectures. Its fundamental advantages are: the time-lead of the slave, the more efficient, and providing a more natural feeling manipulation, and the fact that incorporating an operator arm model leads to more credible stability results. Finally, its simplicity allows less likely to fail local control techniques to be employed. However, a significant advantage for the enhanced Yokokohji and Yoshikawa architecture results from the very fact that it’s a conservative modification of current designs. Under large prediction errors, it can provide robustness through directing the master and slave states to their means and, since it relies on the passivity of the mechanical part of the system, it would not confuse the operator. An experimental implementation of the techniques will provide further evidence for the performance of the proposed architectures. The employment of neural networks and fuzzy logic, which will provide an adaptive model of the human arm and robustifying control terms, is scheduled for the near future.
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Wireless technology based pervasive healthcare has been proposed in many applications such as disease management and accident prevention for cost saving and promoting citizen’s wellbeing. However, the emphasis so far is on the artefacts with limited attentions to guiding the development of an effective and efficient solution for pervasive healthcare. Therefore, this paper aims to propose a framework of multi-agent systems design for pervasive healthcare by adopting the concept of pervasive informatics and using the methods of organisational semiotics. The proposed multi-agent system for pervasive healthcare utilises sensory information to support healthcare professionals for providing appropriate care. The key contributions contain theoretical aspect and practical aspect. In theory, this paper articulates the information interactions between the pervasive healthcare environment and stakeholders by using the methods of organisational semiotics; in practice, the proposed framework improves the healthcare quality by providing appropriate medical attentions when and as needed. In this paper, both systems and functional architecture of the multi-agent system are elaborated with the use of wireless technologies such as RFID and wireless sensor networks. The future study will focus on the implementation of the proposed framework.
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Chemotaxis is one of the best characterised signalling systems in biology. It is the mechanism by which bacteria move towards optimal environments and is implicated in biofilm formation, pathogenesis and symbiosis. The properties of the bacterial chemosensory response have been described in detail for the single chemosensory pathway of Escherichia coli. We have characterised the properties of the chemosensory response of Rhodobacter sphaeroides, an -proteobacterium with multiple chemotaxis pathways, under two growth conditions allowing the effects of protein expression levels and cell architecture to be investigated. Using tethered cell assays we measured the responses of the system to step changes in concentration of the attractant propionate and show that, independently of the growth conditions, R. sphaeroides is chemotactic over at least five orders of magnitude and has a sensing profile following Weber’s law. Mathematical modelling also shows that, like E. coli, R. sphaeroides is capable of showing Fold-Change Detection (FCD). Our results indicate that general features of bacterial chemotaxis such as the range and sensitivity of detection, adaptation times, adherence to Weber’s law and the presence of FCD may be integral features of chemotaxis systems in general, regardless of network complexity, protein expression levels and cellular architecture across different species.
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In any wide-area distributed system there is a need to communicate and interact with a range of networked devices and services ranging from computer-based ones (CPU, memory and disk), to network components (hubs, routers, gateways) and specialised data sources (embedded devices, sensors, data-feeds). In order for the ensemble of underlying technologies to provide an environment suitable for virtual organisations to flourish, the resources that comprise the fabric of the Grid must be monitored in a seamless manner that abstracts away from the underlying complexity. Furthermore, as various competing Grid middleware offerings are released and evolve, an independent overarching monitoring service should act as a corner stone that ties these systems together. GridRM is a standards-based approach that is independent of any given middleware and that can utilise legacy and emerging resource-monitoring technologies. The main objective of the project is to produce a standardised and extensible architecture that provides seamless mechanisms to interact with native monitoring agents across heterogeneous resources.
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This chapter examines the importance of legitimacy for international organizations, and their efforts to legitimate themselves vis-à-vis different audiences. Legitimacy, which for decades barely featured in the scholarly analysis of international organizations, has since the late 1990s been an increasingly important lens through which the processes, practices, and structures of international organizations have been examined. The chapter makes three main arguments. First, it argues that in most international organizations the most important actors engaging in legitimation efforts are not the supranational bureaucracies, but member states. This has important implications for our understanding of the purposes of seeking legitimacy, and for the possible practices. Second, legitimacy and legitimation serve a range of purposes for these states, beyond achieving greater compliance with their decisions, which has been one of the key functional logics highlighted for legitimacy in the literature. Instead, legitimacy is frequently sought to exclude outsiders from the functional or territorial domains affected by an international organization’s authority, or to maintain external material and political support for existing arrangements. Third, one of the most prominent legitimation efforts, institutional reforms, often prioritizes form over function, signalling to important and powerful audiences to encourage their continued material and political support. To advance these arguments, the chapter is divided into four sections. The first develops the concept of legitimacy and its application to international organizations, and then asks why their legitimacy has become such an important intellectual and political concern in recent years. The second part will look in more detail at the legitimation practices of international organizations, focusing on who engages in these practices, who the key audiences are, and how legitimation claims are advanced. The third section will look in more detail at one of the most common forms of legitimation – institutional reform – through the lens of two such reforms in international organizations: efforts towards greater interoperability in NATO, and the establishment of the African Peace and Security Architecture in the African Union (AU). The chapter will conclude with some reflections of the contribution that a legitimacy perspective has made to our understanding of the practices of international organizations.
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In this book essay I argue that modern and contemporary works of art (i.e. paintings, photographs, films, and videos) really ought to retrieve something of their auratic-character, which turns the physical toward the metaphysical, the material toward the immaterial, the visible toward the invisible - making artworks, ‘things among things, something other than [a] thing’ (Theodor W. Adorno, Aesthetic Theory, 86). There is, perhaps, an aura to art or art is a medium or a conduit or a technology for rediscovering and reproducing aura, which makes it something other than a mere thing. Such works of art are constitutively enigmatic, a certain form of magic making: they (re-)distribute the visible and the invisible, they (re-)configure appearance and disappearance. Such works of art may become visual events, which begin an education in and through (dis-)appearances. To achieve this end, I detail Theodor W. Adorno’s and Walter Benjamin’s respective theories of (art’s) aura in the age of technological reproducibility, which I relate to Jacques Rancière’s more recent discussion of the ‘pensive image,’ and I focus my reading on a number of works by Susan Hiller (photographs), John Constable (paintings), Alfred Stieglitz (photographs), and Tacita Dean (photograph and 16mm film).
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Architectures based on Coordinated Atomic action (CA action) concepts have been used to build concurrent fault-tolerant systems. This conceptual model combines concurrent exception handling with action nesting to provide a general mechanism for both enclosing interactions among system components and coordinating forward error recovery measures. This article presents an architectural model to guide the formal specification of concurrent fault-tolerant systems. This architecture provides built-in Communicating Sequential Processes (CSPs) and predefined channels to coordinate exception handling of the user-defined components. Hence some safety properties concerning action scoping and concurrent exception handling can be proved by using the FDR (Failure Divergence Refinement) verification tool. As a result, a formal and general architecture supporting software fault tolerance is ready to be used and proved as users define components with normal and exceptional behaviors. (C) 2010 Elsevier B.V. All rights reserved.
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AI planning systems tend to be disembodied and are not situated within the environment for which plans are generated, thus losing information concerning the interaction between the system and its environment. This paper argues that such information may potentially be valuable in constraining plan formulation, and presents both an agent- and domainindependent architecture that extends the classical AI planning framework to take into account context, or the interaction between an autonomous situated planning agent and its environment. The paper describes how context constrains the goals an agent might generate, enables those goals to be prioritised, and constrains plan selection.
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Esta dissertação fala sobre o corpo. Mais especificamente sobre representações de corpo adolescente feminino produzidas e/ou veiculadas pela revista Capricho. Considerada por mim como um produto da mídia cujas imagens e textos falam às adolescentes deste tempo, analisei todas as edições publicadas nos anos de 2000 e 2001 buscando compreender o que a Capricho ensina às garotas com relação aos seus corpos. Fundamentada no campo teórico dos Estudos Culturais e na História do Corpo, teci minhas análises a partir de três temas: saúde, beleza e moda. Temas esses que emergiram da própria revista uma vez que ela está a falar deles o tempo todo. Decorrente das análises realizadas é possível afirmar que a Capricho, como parte integrante de uma pedagogia cultural, educa as garotas no que respeita à construção de um corpo jovem, moderno e saudável. Um corpo que, ao ser visto, sustenta um look. O look produzido pelas suas páginas e para o qual a garota deve investir diferenciados esforços, seja na aquisição de um jeito atlético e saudável de ser, seja na valorização da magreza e, ainda, na composição de um estilo baseado nos hits da moda.
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This thesis presents the study and development of fault-tolerant techniques for programmable architectures, the well-known Field Programmable Gate Arrays (FPGAs), customizable by SRAM. FPGAs are becoming more valuable for space applications because of the high density, high performance, reduced development cost and re-programmability. In particular, SRAM-based FPGAs are very valuable for remote missions because of the possibility of being reprogrammed by the user as many times as necessary in a very short period. SRAM-based FPGA and micro-controllers represent a wide range of components in space applications, and as a result will be the focus of this work, more specifically the Virtex® family from Xilinx and the architecture of the 8051 micro-controller from Intel. The Triple Modular Redundancy (TMR) with voters is a common high-level technique to protect ASICs against single event upset (SEU) and it can also be applied to FPGAs. The TMR technique was first tested in the Virtex® FPGA architecture by using a small design based on counters. Faults were injected in all sensitive parts of the FPGA and a detailed analysis of the effect of a fault in a TMR design synthesized in the Virtex® platform was performed. Results from fault injection and from a radiation ground test facility showed the efficiency of the TMR for the related case study circuit. Although TMR has showed a high reliability, this technique presents some limitations, such as area overhead, three times more input and output pins and, consequently, a significant increase in power dissipation. Aiming to reduce TMR costs and improve reliability, an innovative high-level technique for designing fault-tolerant systems in SRAM-based FPGAs was developed, without modification in the FPGA architecture. This technique combines time and hardware redundancy to reduce overhead and to ensure reliability. It is based on duplication with comparison and concurrent error detection. The new technique proposed in this work was specifically developed for FPGAs to cope with transient faults in the user combinational and sequential logic, while also reducing pin count, area and power dissipation. The methodology was validated by fault injection experiments in an emulation board. The thesis presents comparison results in fault coverage, area and performance between the discussed techniques.
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The establishment of the Nova Lei de Diretrizes e Bases da Educação Nacional (New Law of Policies and Basis of the National Education) was a mark for the Brazilian educational sector. The institutions of advanced education began to seek two major objectives: the continuous improvement of your academic, pedagogic and administrative practice and the elimination of resources waste. Beyond the implementation of the New Law of Policies and Basis of the National Education, many were the factors that contributed for the change of the paradigms of management of the Institutions of Advanced Education in Brazil. Some of these factors are the following: a) Increasing competition. The competition, each time more present in the day-to- day of the Institutions of Advanced Education, that was regional and closed by, it¿s now professional and global.b) Implantation of the mechanism of quality control, for example the Provão (Exam), by the Ministry of Education.c) Increasing demand for the advanced courses, since the number of students concluding the Middle level courses has being increasing gradually in the last years. d) Education has become a critical factor in the competition between nations, regions and companies.In the present moment, marked by intense competition, complex academic and administrative processes, technologic information as a condition ¿ sine qua non¿ for the decisive process and the exigency for modern and cooperated management, demands big changes in the way the educational institutions manage their resources and evaluate the performance of their administrators.The study demonstrates the pressing necessity of implanting a Control Management that will assist the administration of the Institution of Advanced Education in a way that will optimize the economic results of the entity, as well as the creation and implementation of the mechanisms that will bring a better understanding of the environment in which the entity lives and operates.
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The continuous search of the increase of the productivity has been facilitating the growing diffusion of modern and advanced technologies, that open new ways for the renovation of the industrial productive process, as well as, to the appearance of modern administration systems that establish ways in direction to the democratization of the social relationships in the organizations. Accompanying that tendency and, motivated by the competitive characteristic of the market of electric energy, Eletronorte, adopted the Total Productive Maintenance - TPM, of japanese origin, as the system of administration of its productive process. This dissertation has as objective, to analyze the methodological content of the Total Productive Maintenance, showing its significance and its reach in the Regional of Transmission of Mato Grosso, adopting the post fordism, as comparison paradigm. The whole study and analysis had as focus the offices of the company and the Substation of Coxipó, placed in the city of Cuiabá, as well as the Substations of Rondonópolis and Sinop, placed in cities with the same name. The offices and the substations are geographically located in the state of Mato Grosso, and under the responsibility of the Regional of Transmission of Mato Grosso, of the Centrais Elétricas do Norte do Brasil SA - Eletronorte. The work method was of qualitative orientation and of case study, through a research of applied nature. The research was accomplished with explanatory and exploratory objectives. They were used as instruments of collection of data the analysis of documents, interviews, and application of questionnaires. The data collected through documents and of the application of questionnaires they were compiled and analyzed. The results of the interviews had for objective to confirm the consistency of the collected data. The obtained results demonstrate increases of productivity of the order of 40%, and reduction of the costs of up to 29%. The study still demonstrated, that TPM provoked significant impacts in the practices you work, denoting the presence of an action managerial dialógica. It was still characterized that the transference of TPM will depend in that context the administration system will be applied, because if this is here different from it studied, there won't be transference warranties.
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The rapid growth of urban areas has a significant impact on traffic and transportation systems. New management policies and planning strategies are clearly necessary to cope with the more than ever limited capacity of existing road networks. The concept of Intelligent Transportation System (ITS) arises in this scenario; rather than attempting to increase road capacity by means of physical modifications to the infrastructure, the premise of ITS relies on the use of advanced communication and computer technologies to handle today’s traffic and transportation facilities. Influencing users’ behaviour patterns is a challenge that has stimulated much research in the ITS field, where human factors start gaining great importance to modelling, simulating, and assessing such an innovative approach. This work is aimed at using Multi-agent Systems (MAS) to represent the traffic and transportation systems in the light of the new performance measures brought about by ITS technologies. Agent features have good potentialities to represent those components of a system that are geographically and functionally distributed, such as most components in traffic and transportation. A BDI (beliefs, desires, and intentions) architecture is presented as an alternative to traditional models used to represent the driver behaviour within microscopic simulation allowing for an explicit representation of users’ mental states. Basic concepts of ITS and MAS are presented, as well as some application examples related to the subject. This has motivated the extension of an existing microscopic simulation framework to incorporate MAS features to enhance the representation of drivers. This way demand is generated from a population of agents as the result of their decisions on route and departure time, on a daily basis. The extended simulation model that now supports the interaction of BDI driver agents was effectively implemented, and different experiments were performed to test this approach in commuter scenarios. MAS provides a process-driven approach that fosters the easy construction of modular, robust, and scalable models, characteristics that lack in former result-driven approaches. Its abstraction premises allow for a closer association between the model and its practical implementation. Uncertainty and variability are addressed in a straightforward manner, as an easier representation of humanlike behaviours within the driver structure is provided by cognitive architectures, such as the BDI approach used in this work. This way MAS extends microscopic simulation of traffic to better address the complexity inherent in ITS technologies.
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Esta dissertação tem como objeto de análise a relaçao educativa implícita na proposta de planejamento participativo do "Programa de Desenvolvimento Rural Integrado da Zona da Mata", de Minas Gerais, ali em execuçao desde 1976. Tal tarefa educativa integra uma ação educacional mais ampla cujo objetivo principal é a transferência de tecnologia - alvo que norteia todo o Programa. A adequação e a inovação tecnológica visam o aumento da produtividade por hectare em cultivos de parceiros e pequenos proprietários: agricultores sem terra e que a tem em pouca quantidade. A necessidade da intervenção na economia local surgiu, basicamente, em decorrência deste problema, que chegou a gerar uma certa movimentação desses produtores no início da década de 60. Ao nível da participação popular pretendida, a proposta buscaria dissimular as desigualdades presentes na sociedade local e, ao mesmo tempo, difundir e formar novos hábitos de consumo, de modo a gerar demanda para insumos agrícolas industrializados. Todavia a prática educativa efetivada possibilitou a emergência das ambigüidades e incoerências presentes na Proposta, assim como das contradições que esta buscava encobrir. Para isso, foi fundamental a experiência do pequeno produtor e do parceiro, adquirida na sua prática diária de trabalho, sobretudo se se considerar que ambos são excluídos da escola.