941 resultados para Modular simulators
Resumo:
The overall aim of the work presented in this paper has been to develop Montgomery modular multiplication architectures suitable for implementation on modern reconfigurable hardware. Accordingly, novel high-radix systolic array Montgomery multiplier designs are presented, as we believe that the inherent regular structure and absence of global interconnect associated with these, make them well-suited for implementation on modern FPGAs. Unlike previous approaches, each processing element (PE) comprises both an adder and a multiplier. The inclusion of a multiplier in the PE means that the need to pre-compute or store any multiples of the operands is avoided. This also allows very high-radix implementations to be realised, further reducing the amount of clock cycles per modular multiplication, while still maintaining a competitive critical delay. For demonstrative purposes, 512-bit and 1024-bit FPGA implementations using radices of 2(8) and 2(16) are presented. The subsequent throughput rates are the fastest reported to date.
Resumo:
Electric vehicles (EVs) and hybrid electric vehicles (HEVs) can reduce greenhouse gas emissions while switched reluctance motor (SRM) is one of the promising motor for such applications. This paper presents a novel SRM fault-diagnosis and fault-tolerance operation solution. Based on the traditional asymmetric half-bridge topology for the SRM driving, the central tapped winding of the SRM in modular half-bridge configuration are introduced to provide fault-diagnosis and fault-tolerance functions, which are set idle in normal conditions. The fault diagnosis can be achieved by detecting the characteristic of the excitation and demagnetization currents. An SRM fault-tolerance operation strategy is also realized by the proposed topology, which compensates for the missing phase torque under the open-circuit fault, and reduces the unbalanced phase current under the short-circuit fault due to the uncontrolled faulty phase. Furthermore, the current sensor placement strategy is also discussed to give two placement methods for low cost or modular structure. Simulation results in MATLAB/Simulink and experiments on a 750-W SRM validate the effectiveness of the proposed strategy, which may have significant implications and improve the reliability of EVs/HEVs.
Resumo:
All-optical approaches to particle acceleration are currently attracting a significant research effort internationally. Although characterized by exceptional transverse and longitudinal emittance, laser-driven ion beams currently have limitations in terms of peak ion energy, bandwidth of the energy spectrum and beam divergence. Here we introduce the concept of a versatile, miniature linear accelerating module, which, by employing laser-excited electromagnetic pulses directed along a helical path surrounding the laser-accelerated ion beams, addresses these shortcomings simultaneously. In a proof-of-principle experiment on a university-scale system, we demonstrate post-acceleration of laser-driven protons from a flat foil at a rate of 0.5 GeVm^-1, already beyond what can be sustained by conventional accelerator technologies, with dynamic beam collimation and energy selection. These results open up new opportunities for the development of extremely compact and cost-effective ion accelerators for both established and innovative applications.
Resumo:
This article discusses a curatorial approach to authorship as a model for thinking about what I describe as an iterative modular poem, a poetic text composed of appropriated segments. As a response to contemporary proliferation of literary and artistic works created by iterative means, i.e. through acts of appropriation, remixing and remediation, the article is an attempt at putting forward ‘the curatorial’ as an emerging paradigm of writing for the twenty-first century. The article approaches established paradigms of authorship, creativity and originality as inadequate with respect to contemporary experimental poetic practices to suggest a shift from creating to collecting and curating as a possible alternative model for thinking about instances of iterative creative writing. The argument focuses on Robert Fitterman’s Holocaust Museum (2011) as an example of an iterative modular poem and a text emblematic of such curatorial approach to authorship.
Resumo:
Pós-graduação em Engenharia de Produção - FEG
Resumo:
Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Automação e Electrónica Industrial
Resumo:
Da necessidade de criação de habitações que se adaptem ao constante dinamismo do ser humano, surgiu a ideia da concepção de um edifício evolutivo com base na construção modular. A construção modular poderá ser entendida como sendo a principal resposta ao combate da construção de estruturas físicas e imóveis, com características inalteráveis ao longo do tempo. Com este trabalho idealizou-se uma habitação evolutiva, baseado nos conceitos da Coordenação Modular, identificando-se as suas especificações, exigências de desempenho e características funcionais. Foi considerada como medida modular base 0,10m. Os módulos foram pensados com o intuito de que o seu desempenho prático seja satisfatório. A sua base estrutural foi executada a partir do rearranjo de contentores marítimos. Previu-se ainda, o uso de coberturas verdes por serem uma solução comprovada de minorar notoriamente o efeito pernicioso que a construção tem sobre o meio ambiente, ao mesmo tempo que apresentam vantagens térmicas e acústicas. A questão do incentivo do uso da pré-fabricação em Portugal a uma maior escala, não poderia ser descurada. A apresentação de eventuais desenvolvimentos futuros é também relevante, dada a importância que é inerente ao âmbito da industrialização da construção. Do estudo realizado ficaram ainda, bem patentes, os benefícios da racionalização e da industrialização, tanto em termos económicos como em termos ambientais. É possível executar um projecto com níveis de perdas mais baixos e com índices de qualidade superiores a um menor preço.
Resumo:
A necessidade de construir que se manifesta em todos os sectores, desde o da habitação, em que o homem recupera da fadiga física e intelectual, consequência da sua actividade diária, até àquele em que exerce a sua actividade de produção ou onde realiza as suas ocupações sociais dos tempos livres, obriga a procurar soluções, para a limitação de espaços - cada vez mais económicos em tempo, dinheiro, materiais e mão de obra. Este objectivo levou ao desenvolvimento de técnicas de pré-fabricação,e bem assim a industrializar a construção, por elementos cada vez maiores - de acordo com os meios mecânicos de que se pode dispor na zona industrial, nos transportes e no estaleiro. Assim, conforme os elementos de construção a colocar em obra são manuseáveis ou, pelas suas dimensões e peso, careçam de meios mecânicos para poderem ser utilizados, a pré fabricação está diferenciada em: a) Pré fabricação ligeira b) Pré fabricação pesada Por outro lado, os diversos materiais que se utilizam na construção permitem a pré fabricação industrial de elementos de construção: metálicos, de madeira, de betão, de pedra, de argila cozida, de vidro, etc.
Resumo:
The electricity market restructuring, along with the increasing necessity for an adequate integration of renewable energy sources, is resulting in an rising complexity in power systems operation. Various power system simulators have been introduced in recent years with the purpose of helping operators, regulators, and involved players to understand and deal with this complex environment. This paper focuses on the development of an upper ontology which integrates the essential concepts necessary to interpret all the available information. The restructuring of MASCEM (Multi-Agent System for Competitive Electricity Markets), and this system’s integration with MASGriP (Multi-Agent Smart Grid Platform), and ALBidS (Adaptive Learning Strategic Bidding System) provide the means for the exemplification of the usefulness of this ontology. A practical example is presented, showing how common simulation scenarios for different simulators, directed to very distinct environments, can be created departing from the proposed ontology.
Resumo:
This paper presents the TEC4SEA research infrastructure created in Portugal to support research, development, and validation of marine technologies. It is a multidisciplinary open platform, capable of supporting research, development, and test of marine robotics, telecommunications, and sensing technologies for monitoring and operating in the ocean environment. Due to the installed research facilities and its privileged geographic location, it allows fast access to deep sea, and can support multidisciplinary research, enabling full validation and evaluation of technological solutions designed for the ocean environment. It is a vertically integrated infrastructure, in the sense that it possesses a set of skills and resources which range from pure conceptual research to field deployment missions, with strong industrial and logistic capacities in the middle tier of prototype production. TEC4SEA is open to the entire scientific and enterprise community, with a free access policy for researchers affiliated with the research units that ensure its maintenance and sustainability. The paper describes the infrastructure in detail, and discusses associated research programs, providing a strategic vision for deep sea research initiatives, within the context of both the Portuguese National Ocean Strategy and European Strategy frameworks.
Resumo:
This paper discusses the development of modular solutions for eco low-cost houses based on a pre-fabricated modular wall system environmentally sustainable, socioeconomically competitive and geared towards developing African nations with a housing deficit. The key point to the research of a modular wall solution is a structural layer complemented with local and materials made by non-specialized workforce. This wall also meets also hydrothermal acoustic and mechanical properties. Thus,the solution also offers good safety and interior comfort conditions to its users while maintaining the flexibility to expand the size of the house. Parameters as dimensions, materials and constructive processes of the existing housing stock were studied. Features such as the family size, typology, different uses, common materials, existing regulations, minimal living conditions, safety and comfort have also been considered to achieve the most efficient solution.
Resumo:
According to Diener (1984), the three primary components of subjective well-being (SWB) are high life satisfaction (LS), frequent positive affect (P A), and infrequent negative affect (NA). The present dissertation extends previous research and theorizing on SWB by testing an innovative framework developed by Shmotkin (2005) in which SWB is conceptualized as an agentic process that promotes and maintains positive functioning. Two key components ofShmotkin's framework were explored in a longitudinal study of university students. In Part 1, SWB was examined as an integrated system of components organized within individuals. Using cluster analysis, five distinct configurations of LS, P A, and NA were identified at each wave. Individuals' SWB configurations were moderately stable over time, with the highest and lowest stabilities observed among participants characterized by "high SWB" and "low SWB" configurations, respectively. Changes in SWB configurations in the direction of a high SWB pattern, and stability among participants already characterized by high SWB, coincided with better than expected mental, physical, and interpersonal functioning over time. More positive levels of functioning and improvements in functioning over time discriminated among SWB configurations. However, prospective effects of SWB configurations on subsequent functioning were not observed. In Part 2, subjective temporal perspective "trajectories" were examined based on individuals' ratings of their past, present, and anticipated future LS. Upward subjective LS trajectories were normative at each wave. Cross-sectional analyses revealed consistent associations between upward subjective trajectories and lower levels of LS, as well as less positive mental, physical, and interpersonal functioning. Upward subjective LS trajectories were biased both with respect to underestimation of past LS and overestimation of future LS, demonstrating their illusional nature. Further, whereas more negative retrospective bias was associated with greater current distress and dysfunction, more positive prospective bias was associated with less positive functioning in the future. Prospective relations, however, were not consistently observed. Thus, steep upward subjective LS trajectory appeared to be a form of wishful-thinking, rather than an adaptive form of selfenhancement. Major limitations and important directions for future research are considered. Implications for Shmotkin's (2005) framework, and for research on SWB more generally, also are discussed