997 resultados para Schmidt, Lars-Henrik
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This paper introduces a new neurofuzzy model construction and parameter estimation algorithm from observed finite data sets, based on a Takagi and Sugeno (T-S) inference mechanism and a new extended Gram-Schmidt orthogonal decomposition algorithm, for the modeling of a priori unknown dynamical systems in the form of a set of fuzzy rules. The first contribution of the paper is the introduction of a one to one mapping between a fuzzy rule-base and a model matrix feature subspace using the T-S inference mechanism. This link enables the numerical properties associated with a rule-based matrix subspace, the relationships amongst these matrix subspaces, and the correlation between the output vector and a rule-base matrix subspace, to be investigated and extracted as rule-based knowledge to enhance model transparency. The matrix subspace spanned by a fuzzy rule is initially derived as the input regression matrix multiplied by a weighting matrix that consists of the corresponding fuzzy membership functions over the training data set. Model transparency is explored by the derivation of an equivalence between an A-optimality experimental design criterion of the weighting matrix and the average model output sensitivity to the fuzzy rule, so that rule-bases can be effectively measured by their identifiability via the A-optimality experimental design criterion. The A-optimality experimental design criterion of the weighting matrices of fuzzy rules is used to construct an initial model rule-base. An extended Gram-Schmidt algorithm is then developed to estimate the parameter vector for each rule. This new algorithm decomposes the model rule-bases via an orthogonal subspace decomposition approach, so as to enhance model transparency with the capability of interpreting the derived rule-base energy level. This new approach is computationally simpler than the conventional Gram-Schmidt algorithm for resolving high dimensional regression problems, whereby it is computationally desirable to decompose complex models into a few submodels rather than a single model with large number of input variables and the associated curse of dimensionality problem. Numerical examples are included to demonstrate the effectiveness of the proposed new algorithm.
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The growth (melt) rate of frazil ice is governed by heat transfer away from (towards) the ice crystal, which can be represented by the Nusselt number. We discuss choices for the Nusselt number and turbulent length scale appropriate for frazil ice and note an inaccuracy in the study ”Frazil evolution in channels“ by Lars Hammar and Hung-Tao Shen, which has also led to potentially significant errors in several other papers. We correct this error and suggest an appropriate strategy for determining the Nusselt number applicable to frazil ice growth and melting.
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Over the last decade, we have seen a massive increase in the construction of wind farms in northern Fennoscandia. Wind farms comprising hundreds of wind turbines are being built, with little knowledge of the possible cumulative adverse effects on the habitat use and migration of semi-domesticated free-ranging reindeer. We assessed how reindeer responded to wind farm construction in an already fragmented landscape, with specific reference to the effects on use of movement corridors and reindeer habitat selection. We used GPS-data from reindeer during calving and post-calving in the MalAyen reindeer herding community in Sweden. We analysed data from the pre-development years compared to the construction years of two relatively small wind farms. During construction of the wind farms, use of original migration routes and movement corridors within 2 km of development declined by 76 %. This decline in use corresponded to an increase in activity of the reindeer measured by increased step lengths within 0-5 km. The step length was highest nearest the development and declining with distance, as animals moved towards migration corridors and turned around or were observed in holding patterns while not crossing. During construction, reindeer avoided the wind farms at both regional and landscape scale of selection. The combined construction activities associated with even a few wind turbines combined with power lines and roads in or close to central movement corridors caused a reduction in the use of such corridors and grazing habitat and increased the fragmentation of the reindeer calving ranges.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Considering the importance of significations in literary works, this paper proposes a comparative study of the image of the Doll's House in Henrik Ibsen's play ADoll's House (1879), and Katherine Mansfield's short story The Doll's House, published in the book The Dove's Nest (1923), based on the theories of Gaston Bachelard and Jean Baudrillard. In both cases, one notices that the presence of this image indicatesnot only the construction of these works' environment, but also a criticism of the bourgeois model of a perfect and flawless society, as the described image refers to. However, even though this image shares the same idea in both works, it will be explored differentlyin each case, whether through the search of Nora's character in escaping social conformity as in Ibsen, or through the subtle childlike game experienced by the Kelvey sisters, asin Mansfield.
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Pós-graduação em Matemática - IBILCE
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The cinematographic language is notedly plural and heterogeneous. There are many filmic elements that “narrate” all the time, in different ways. Besides enumerating some of them, this study seeks to analyse if the criticism is attentive to all of these tools or if it sticks only to some of them. It’s also reflects if this activity uses more objectives or subjectives aspects as basis for its conclusions. Here, a very specific field was chosen: the study is done by a comparative analysis of the reception of Brazilian’s and European’s criticism from two Lars Von Trier’s films, Antichrist and Melancholia. After explaining how the narrative elements are used in the cinema, it’s demonstrated that, in general, the criticism is negligent and does not analyze all of those tools. In some cases, the analysis of some elements is done in a superficial way, so others aspects can be highlighted
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As espécies estudadas neste projeto, Dendropsophus nanus e Dendropsophus sanborni, são pererecas de pequeno porte, morfologicamente semelhantes e ocupam nichos similares. O presente trabalho foi realizado na Floresta Estadual Edmundo Navarro de Andrade, município de Rio Claro, estado de São Paulo e teve como objetivo obter informações acerca da biologia reprodutiva de ambas as espécies. Os principais resultados obtidos foram referentes à: (1) Relações de tamanho-fecundidade em fêmeas de D. nanus, sendo que foi significativa a correlação entre número de ovos e comprimento rostro-cloacal de fêmeas, o que não ocorreu para correlações entre tamanho dos ovos e CRC de fêmeas e entre tamanho e número de ovos, (2) Seleção do tamanho dos machos em D. nanus, com as fêmeas aparentemente acasalando com machos proporcionalmente mais leves e (3) Comportamento de desova de D. sanborni semelhante ao relatado para D. werneri, havendo dois tipos de interação parecidos: um envolvendo movimentos da cabeça e o outro das patas traseiras do macho, ambos descritos pela primeira vez para D. sanborni neste estudo.
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This meta-analysis of land-cover transformations of the past 10-15 years in tropical forest-agriculture frontiers world-wide shows that swidden agriculture decreases in landscapes with access to local, national and international markets that encourage cattle production and cash cropping, including biofuels. Conservation policies and practices also accelerate changes in swidden by restricting forest clearing and encouraging commercial agriculture. However, swidden remains important in many frontier areas where farmers have unequal or insecure access to investment and market opportunities, or where multi-functionality of land uses has been preserved as a strategy to adapt to current ecological, economic and political circumstances. In some areas swidden remains important simply because intensification is not a viable choice, for example when population densities and/or food market demands are low. The transformation of swidden landscapes into more intensive land uses has generally increased household incomes, but has also led to negative effects on the social and human capital of local communities to varying degrees. From an environmental perspective, the transition from swidden to other land uses often contributes to permanent deforestation, loss of biodiversity, increased weed pressure, declines in soil fertility, and accelerated soil erosion. Our prognosis is that, despite the global trend towards land use intensification, in many areas swidden will remain part of rural landscapes as the safety component of diversified systems, particularly in response to risks and uncertainties associated with more intensive land use systems. (C) 2011 Elsevier Ltd. All rights reserved.
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I poriferi rappresentano un importante campo di ricerca anche in ambito applicativo in quanto potenzialmente utili come fonte di metaboliti secondari da impiegarsi in ambito clinico (antitumorali, antibiotici, antivirali, ecc.) e industriale (antifouling). I processi di biosilicificazione interessano invece per aspetti legati alle biotecnologie marine. Questo Phylum ha un importante ruolo strutturale e funzionale nell’ecologia dei popolamenti bentonici, in quanto può essere dominante in numerosi habitat e svolgere un ruolo ecologico fondamentale nelle dinamiche degli ecosistemi marini. Per questo, la variazione spaziale e temporale della loro abbondanza può avere effetti considerevoli su altri membri della comunità. Lo studio delle dinamiche di popolazione e del ciclo riproduttivo dei poriferi potrebbe permettere di valutare come i cambiamenti climatici ne influenzino la crescita e la riproduzione e potrebbe quindi fornire una base per lo sviluppo di corrette tecniche di gestione ambientale. La spugna Axinella polypoides è inserita all’interno delle liste di protezione della Convenzione di Berna e di Barcellona, dove sono elencate le specie da proteggere perché minacciate o in pericolo di estinzione. Questa specie, avendo una morfologia eretta, è fortemente minacciata soprattutto da attività antropiche quali pesca e ancoraggi, ma nonostante questo la letteratura relativa ad essa è scarsa, La sua importanza è legata soprattutto al recente utilizzo come modello per numerosi esperimenti. A. polypoides rappresenta, infatti, il più basso livello nella scala evolutiva in cui sono stati rinvenuti meccanismi biochimici cellulari di reazione all’aumento di temperatura (incremento dell’attività ADP-ribosil ciclasica, sintesi di ossido nitrico) tipici degli organismi superiori. Lo scopo di questa tesi è di aumentare le conoscenze sull’ecologia e sulla biologia di questo porifero, al fine di consentire una migliore predisposizione di eventuali piani di tutela. Dallo studio delle colonie effettuato presso l’Isola Gallinara (SV), emerge una dinamica di crescita lenta ed un ciclo riproduttivo estivo, coerentemente con quanto osservato per altre specie mediterranee del genere Axinella. Le analisi istologiche effettuate hanno mostrato variabilità temporale nella densità e nella dimensione di particolari cellule sferulose, che si ipotizza siano collegate a fenomeni di proliferazione cellulare e rigenerazione in seguito a danni. È stata individuata inoltre la presenza di una particolare tipologia cellulare dendritica la cui funzione si ritiene abbia affinità con le funzioni sensoriali di Phyla superiori. Queste osservazioni, e l’evidente vulnerabilità della specie agli impatti antropici, hanno evidenziato la necessità di sviluppare adeguati piani di monitoraggio e di conservazione.
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To report our initial experience with dual-energy computed-tomography (CT) cholangiography in potential donors for living-related liver transplantation.
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To assess the diagnostic accuracy, image quality, and radiation dose of an iterative reconstruction algorithm compared with a filtered back projection (FBP) algorithm for abdominal computed tomography (CT) at different tube voltages.