906 resultados para New Space Vector Modulation


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Há muitos anos, técnicas de Computação Evolucionária vem sendo aplicadas com sucesso na solução dos mais variados tipos de problemas de otimização. Na constante procura pelo ótimo global e por uma melhor exploração da superfície de busca, as escolhas para ajustar estes métodos podem ser exponencialmente complexas e requerem uma grande quantidade de intervenção humana. Estes modelos tradicionais darwinianos apóiam-se fortemente em aleatoriedade e escolhas heurísticas que se mantém fixas durante toda a execução, sem que acompanhem a variabilidade dos indivíduos e as eventuais mudanças necessárias. Dadas estas questões, o trabalho introduz a combinação de aspectos da Teoria do Design Inteligente a uma abordagem hibrida de algoritmo evolucionário, através da implementação de um agente inteligente o qual, utilizando lógica fuzzy, monitora e controla dinamicamente a população e seis parâmetros definidos de uma dada execução, ajustando-os para cada situação encontrada durante a busca. Na avaliação das proposições foi construído um protótipo sobre a implementação de um algoritmo genético para o problema do caixeiro viajante simétrico aplicado ao cenário de distância por estradas entre as capitais brasileiras, o que permitiu realizar 580 testes, simulações e comparações entre diferentes configurações apresentadas e resultados de outras técnicas. A intervenção inteligente entrega resultados que, com sucesso em muitos aspectos, superam as implementações tradicionais e abrem um vasto espaço para novas pesquisas e estudos nos aqui chamados: “Algoritmos Evolucionários Híbridos Auto-Adaptáveis”, ou mesmo, “Algoritmos Evolucionários Não-Darwinianos”.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

O Reduto é uma área contígua ao centro da cidade de Belém surgida na segunda metade do século XVIII com a construção de uma fortificação militar. Foi efetivamente ocupado durante o século XIX, quando viveu um período de intensa atividade comercial resultante da economia da borracha. Na primeira década do século XX com a implantação de um projeto modernizador surgiram obras na cidade que forçaram uma reestruturação do espaço urbano. Enquanto o restante da cidade era embelezado, a área do Reduto, para atender aos interesses capitalistas da economia exportadora, sofria uma descaracterização no seu espaço original: o aterramento da sua doca e a quebra do seu movimentado comércio. Entretanto, novas formas espaciais foram surgindo no bairro. Ocupando uma posição conveniente, a margem imediata da baía, o Reduto tornou-se uma área atrativa para a instalação de fábricas e foi pouco a pouco assumindo ares de bairro industrial. Funcionários, comerciantes e empresários de várias nacionalidades, ou simplesmente operários em busca de trabalho deram ao Reduto até meados do século XX características bem particulares que ficaram marcadas no imaginário coletivo da cidade e ainda hoje são presentes na memória dos seus antigos moradores.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Geografia - IGCE

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Geografia - FCT

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Estudos Literários - FCLAR

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We discuss Henry Miller's novel Tropic of Cancer based on the concept of nomadism, as coined by Deleuze and Guattari. The relation between philosophy and literature is very productive for both. A phenomenon of dual capture between these two areas that is characteristic of a nomadic thinking: literature that engenders philosophy which, in turn, engenders literature, establishing connections, new relations between terms in a distinct nomad variation that dismisses the classical image of thought of its eminence: a perspective between philosophy and literature as form of discussing the nomadism in Miller's novel. Thus, the linkage between philosophy and literature aims to capture the Millerian paths on this new space of thought, which is achieved by giving up any origin, human or divine, and stands as productive thought that affirms the real in a combat waged against the faculty of judgment, or simply of Judgment, in all its forms.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Física - FEG

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A faithful depiction of the tropical atmosphere requires three-dimensional sets of observations. Despite the increasing amount of observations presently available, these will hardly ever encompass the entire atmosphere and, in addition, observations have errors. Additional (background) information will always be required to complete the picture. Valuable added information comes from the physical laws governing the flow, usually mediated via a numerical weather prediction (NWP) model. These models are, however, never going to be error-free, why a reliable estimate of their errors poses a real challenge since the whole truth will never be within our grasp. The present thesis addresses the question of improving the analysis procedures for NWP in the tropics. Improvements are sought by addressing the following issues: - the efficiency of the internal model adjustment, - the potential of the reliable background-error information, as compared to observations, - the impact of a new, space-borne line-of-sight wind measurements, and - the usefulness of multivariate relationships for data assimilation in the tropics. Most NWP assimilation schemes are effectively univariate near the equator. In this thesis, a multivariate formulation of the variational data assimilation in the tropics has been developed. The proposed background-error model supports the mass-wind coupling based on convectively-coupled equatorial waves. The resulting assimilation model produces balanced analysis increments and hereby increases the efficiency of all types of observations. Idealized adjustment and multivariate analysis experiments highlight the importance of direct wind measurements in the tropics. In particular, the presented results confirm the superiority of wind observations compared to mass data, in spite of the exact multivariate relationships available from the background information. The internal model adjustment is also more efficient for wind observations than for mass data. In accordance with these findings, new satellite wind observations are expected to contribute towards the improvement of NWP and climate modeling in the tropics. Although incomplete, the new wind-field information has the potential to reduce uncertainties in the tropical dynamical fields, if used together with the existing satellite mass-field measurements. The results obtained by applying the new background-error representation to the tropical short-range forecast errors of a state-of-art NWP model suggest that achieving useful tropical multivariate relationships may be feasible within an operational NWP environment.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Facial expression recognition is one of the most challenging research areas in the image recognition ¯eld and has been actively studied since the 70's. For instance, smile recognition has been studied due to the fact that it is considered an important facial expression in human communication, it is therefore likely useful for human–machine interaction. Moreover, if a smile can be detected and also its intensity estimated, it will raise the possibility of new applications in the future

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This thesis explores the function of the theatre in Derek Walcott's literary achievements. Focusing on the semiotic theories that characterize the study of drama as a literary text and as a staged text, the initial approach aims at creating a relationship between semiotics and postcolonial theories. In particular Pavis's concept of intercultural semiotics and Peter Brook's innovative visions about the regenerative function of the space of the theatre represent a useful theoretical basis to consider the specificity of postcolonial theatre as an innovative space, where new cultural meanings emerge. Derek Walcott's dramatic production is studied according to this approach, in order to be defined as a new hybrid, syncretic and multicultural space. After considering the development of drama from a postcolonial and Caribbean perspective, this study begins with an insight into Walcott's views on theatre, taking into consideration his linguistic depth, linked to the European tradition, but also his strong concern with the Caribbean public's cultural needs. The double tension characterizing Walcott's cultural identity as well as his art represents an essential element to analyse his dramatic texts. With an ambivalent approach, which takes into consideration language and performance, this thesis offers an insight into Walcott's plays to detect their postcolonial and multicultural elements. The analysis of the different texts are divided into two chapters (third and fourth). The third chapters - mainly focused on postcolonial themes - explores issues such as language, identity and space, whereas the fourth chapter centers on multiculturalism in text and performance. Dealing with interracial interactions, issues like re-writing classical texts and the manipulation of personal and collective memory as a way to re- establish new historical perspectives, the last part of the thesis aims at demonstrating the idea that Walcott has created a new space in the theatre made by the harmonic fusion of different and opposed cultural elements, which are visible in the literary as well as in the staged text. The textual perspective of Walcott's drama fits into Pavis's definition of intercultural semiotics, as the faithful representation of a multicultural creole society: that of the West Indies.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

RAGE mediates diverse physiological and pathological effects by binding a variety of ligands. Despite incomplete understanding of RAGE-mediated disorders soluble RAGE (sRAGE) has been identified as a potential biomarker for RAGE-related diseases and possibly represents a hopeful pharmaceutical against RAGE-mediated disorders. Nevertheless, the source of sRAGE remains poorly investigated. Currently sRAGE is thought to be derived exclusively from alternative splicing of mRNA. In this thesis it was investigated whether sRAGE can also be released as a result of ectodomain shedding of full-length RAGE. Using cells overexpressing RAGE as a model system, it was demonstrated clearly that RAGE undergoes ectodomain shedding in both constitutive and regulated manner. Several stimuli including PMA, AMPA, calcium and chelerythrine stimulated the release of sRAGE into cell culture medium. Moreover, possible mechanisms that regulate ectodomain shedding of RAGE were investigated and it was found that shedding of RAGE is likely independent from PKC and MAPK pathways. By using gain of function and loss of function approaches MMP9 but not ADAM10, ADAM17 or MT1-MMP was characterized as the metalloproteinase that mediates shedding of RAGE. Furthermore, it was shown that cytoplasmic domain of RAGE is not essential for shedding of RAGE. In addition, the potential cleavage site of RAGE by MMP9 was investigated and a lack of sequence specificity for the RAGE processing proteinase was demonstrated by mutation analysis. Finally the physiopathological significance of shedding of RAGE is discussed. In conclusion, for the first time ectodomain shedding of human RAGE and the underlying regulatory mechanisms were investigated. The data open a new field for modulation of RAGE shedding as a novel intervention approach against RAGE-mediated diseases.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Le scelte di asset allocation costituiscono un problema ricorrente per ogni investitore. Quest’ultimo è continuamente impegnato a combinare diverse asset class per giungere ad un investimento coerente con le proprie preferenze. L’esigenza di supportare gli asset manager nello svolgimento delle proprie mansioni ha alimentato nel tempo una vasta letteratura che ha proposto numerose strategie e modelli di portfolio construction. Questa tesi tenta di fornire una rassegna di alcuni modelli innovativi di previsione e di alcune strategie nell’ambito dell’asset allocation tattica, per poi valutarne i risvolti pratici. In primis verificheremo la sussistenza di eventuali relazioni tra la dinamica di alcune variabili macroeconomiche ed i mercati finanziari. Lo scopo è quello di individuare un modello econometrico capace di orientare le strategie dei gestori nella costruzione dei propri portafogli di investimento. L’analisi prende in considerazione il mercato americano, durante un periodo caratterizzato da rapide trasformazioni economiche e da un’elevata volatilità dei prezzi azionari. In secondo luogo verrà esaminata la validità delle strategie di trading momentum e contrarian nei mercati futures, in particolare quelli dell’Eurozona, che ben si prestano all’implementazione delle stesse, grazie all’assenza di vincoli sulle operazioni di shorting ed ai ridotti costi di transazione. Dall’indagine emerge che entrambe le anomalie si presentano con carattere di stabilità. I rendimenti anomali permangono anche qualora vengano utilizzati i tradizionali modelli di asset pricing, quali il CAPM, il modello di Fama e French e quello di Carhart. Infine, utilizzando l’approccio EGARCH-M, verranno formulate previsioni sulla volatilità dei rendimenti dei titoli appartenenti al Dow Jones. Quest’ultime saranno poi utilizzate come input per determinare le views da inserire nel modello di Black e Litterman. I risultati ottenuti, evidenziano, per diversi valori dello scalare tau, extra rendimenti medi del new combined vector superiori al vettore degli extra rendimenti di equilibrio di mercato, seppur con livelli più elevati di rischio.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Sustainable natural resource use requires that multiple actors reassess their situation in a systemic perspective. This can be conceptualised as a social learning process between actors from rural communities and the experts from outside organisations. A specifically designed workshop oriented towards a systemic view of natural resource use and the enhancement of mutual learning between local and external actors, provided the background for evaluating the potentials and constraints of intensified social learning processes. Case studies in rural communities in India, Bolivia, Peru and Mali showed that changes in the narratives of the participants of the workshop followed a similar temporal sequence relatively independently from their specific contexts. Social learning processes were found to be more likely to be successful if they 1) opened new space for communicative action, allowing for an intersubjective re-definition of the present situation, 2) contributed to rebalance the relationships between social capital and social, emotional and cognitive competencies within and between local and external actors.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The present paper discusses a conceptual, methodological and practical framework within which the limitations of the conventional notion of natural resource management (NRM) can be overcome. NRM is understood as the application of scientific ecological knowledge to resource management. By including a consideration of the normative imperatives that arise from scientific ecological knowledge and submitting them to public scrutiny, ‘sustainable management of natural resources’ can be recontextualised as ‘sustainable governance of natural resources’. This in turn makes it possible to place the politically neutralising discourse of ‘management’ in a space for wider societal debate, in which the different actors involved can deliberate and negotiate the norms, rules and power relations related to natural resource use and sustainable development. The transformation of sustainable management into sustainable governance of natural resources can be conceptualised as a social learning process involving scientists, experts, politicians and local actors, and their corresponding scientific and non-scientific knowledges. The social learning process is the result of what Habermas has described as ‘communicative action’, in contrast to ‘strategic action’. Sustainable governance of natural resources thus requires a new space for communicative action aiming at shared, intersubjectively validated definitions of actual situations and the goals and means required for transforming current norms, rules and power relations in order to achieve sustainable development. Case studies from rural India, Bolivia and Mali explore the potentials and limitations for broadening communicative action through an intensification of social learning processes at the interface of local and external knowledge. Key factors that enable or hinder the transformation of sustainable management into sustainable governance of natural resources through social learning processes and communicative action are discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Mapping ecosystem services (ES) and their trade-offs is a key requirement for informed decision making for land use planning and management of natural resources that aim to move towards increasing the sustainability of landscapes. The negotiations of the purposes of landscapes and the services they should provide are difficult as there is an increasing number of stakeholders active at different levels with a variety of interests present on one particular landscape.Traditionally, land cover data is at the basis for mapping and spatial monitoring of ecosystem services. In light of complex landscapes it is however questionable whether land cover per se and as a spatial base unit is suitable for monitoring and management at the meso-scale. Often the characteristics of a landscape are defined by prevalence, composition and specific spatial and temporal patterns of different land cover types. The spatial delineation of shifting cultivation agriculture represents a prominent example of a land use system with its different land use intensities that requires alternative methodologies that go beyond the common remote sensing approaches of pixel-based land cover analysis due to the spatial and temporal dynamics of rotating cultivated and fallow fields.Against this background we advocate that adopting a landscape perspective to spatial planning and decision making offers new space for negotiation and collaboration, taking into account the needs of local resource users, and of the global community. For this purpose we introduce landscape mosaicsdefined as new spatial unit describing generalized land use types. Landscape mosaics have allowed us to chart different land use systems and land use intensities and permitted us to delineate changes in these land use systems based on changes of external claims on these landscapes. The underlying idea behindthe landscape mosaics is to use land cover data typically derived from remote sensing data and to analyse and classify spatial patterns of this land cover data using a moving window approach. We developed the landscape mosaics approach in tropical, forest dominated landscapesparticularly shifting cultivation areas and present examples ofour work from northern Laos, eastern Madagascarand Yunnan Province in China.