921 resultados para Dimension fractale
Resumo:
The study of interrelationships between soil structure and its functional properties is complicated by the fact that the quantitative description of soil structure is challenging. Soil scientists have tackled this challenge by taking advantage of approaches such as fractal geometry, which describes soil architectural complexity through a scaling exponent (D) relating mass and numbers of particles/aggregates to particle/aggregate size. Typically, soil biologists use empirical indices such as mean weight diameters (MWD) and percent of water stable aggregates (WSA), or the entire size distribution, and they have successfully related these indices to key soil features such as C and N dynamics and biological promoters of soil structure. Here, we focused on D, WSA and MWD and we tested whether: D estimated by the exponent of the power law of number-size distributions is a good and consistent correlate of MWD and WSA; D carries information that differs from MWD and WSA; the fraction of variation in D that is uncorrelated with MWD and WSA is related to soil chemical and biological properties that are thought to establish interdependence with soil structure (e.g., organic C, N, arbuscular mycorrhizal fungi). We analysed observational data from a broad scale field study and results from a greenhouse experiment where arbuscular mycorrhizal fungi (AMF) and collembola altered soil structure. We were able to develop empirical models that account for a highly significant and large portion of the correlation observed between WSA and MWD but we did not uncover the mechanisms that underlie this correlation. We conclude that most of the covariance between D and soil biotic (AMF, plant roots) and abiotic (C. N) properties can be accounted for by WSA and MWD. This result implies that the ecological effects of the fragmentation properties described by D and generally discussed under the framework of fractal models can be interpreted under the intuitive perspective of simpler indices and we suggest that the biotic components mostly impacted the largest size fractions, which dominate MWD, WSA and the scaling exponent ruling number-size distributions. (C) 2010 Elsevier Ltd. All rights reserved.
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This paper presents a 3D simulation system which is employed in order to predict cutting forces and tool deflection during end-milling operation. In order to verify the accuracy of 3D simulation, results (cutting forces and tool deflection) were compared with those based on the theoretical relationships, in terms of agreement with experiments. The results obtained indicate that the simulation is capable of predicting the cutting forces and tool deflection.
Hygrothermal Features of Laterite Dimension Stones for Sub-Saharan Residential Building Construction
Resumo:
The building sector is widely recognized as having a major impact on sustainable development. Both in developed and developing countries, sustainability in buildings approaches are growing. Laterite dimension stone (LDS) is a building material that was traditionally used in sub-Saharan Africa, but its technical features still need to be assessed. This article presents some results of a study focused on the characterization of LDS exploited in Burkina Faso for building purposes. The measured average thermal conductivity is 0.51 W/mK, which increases with water content and evolves with the specific gravity and with porosity. Rock mineral phases (quartz, goethite, hematite, magnetite) are cemented by kaolinite. The porosity of the material is high (30%), with macropores visible on the surface and found in the rock inner structure as well. Results from the hygrothermal monitoring of a pilot building are also presented.
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Conventional wisdom has it that the EU is unable to promote viable social integration, which contrasts with its commitments to improving working and living conditions and to social values and goals such as solidarity, social protection and social inclusion. This
article challenges two diff erent standpoints: on the one hand, competitive neoliberalism demands that the EU focuses on economic integration through legally binding internal market and competition rules even if Member States can only maintain a limited commitment to social inclusion, while authors defending the social models unique to the continent of Europe demand that the EU rescinds some of its established legal principles in order to make breathing space for Member States to maintain market correcting social policies. Both positions convene that there should be no genuine social policy at EU level.
This article uses scenarios of widely discussed rulings by the Court of Justice to illustrate that legally enforceable economic integration would prevent most Member States from achieving sustainable health services, labour relations and free university education on the basis of national closure. Since the EU has limited legislative competences to create EU level institutions to balance inequalities, it derives a Constitution of Social Governance from the EU’s values, proposing that the Court of Justice develops its urisprudence into an instrument for challenging European disunion induced by new EU economic governance
Resumo:
The award of the Nobel Peace Prize to the European Union in 2012 was a reminder of the role of European integration in peacebuilding after the Second World War. For the 'Founding Fathers' of the European integration project, cross-border-cooperation was an integral element in building Europe's peace. Yet, in a Western Europe largely at peace for generations, peacebuilding as a relevant objective for European integration may be questioned. Moreover, the contribution of cross-border cooperation to conflict amelioration may be challenged on the grounds of its overwhelming economic focus. However, enlargement into Central Eastern Europe highlights once again the necessity of a peacebuilding objective for the European Union because of the multitude of real and potential conflicts encompassed within its expanded policy orbit. Drawing on evidence from selected 'borderscapes', this study examines 25 years of European Union cross-border cooperation as conflict amelioration and assesses its prospects in a political climate that emphasises borders as security barriers.
Resumo:
Famous for being the first foreign feature film that obtained permission to shoot in the Forbidden City, The Last Emperor (1987) is also one of the most ambitious and expensive independent productions of its time, awarded four Golden Globes and nine Academy Awards, including Best Picture. In addition, The Last Emperor can be considered as one of the first attempts of cinematic collaboration between West and East, in a period of cultural and economic transformations witnessed by China. This article aims to offer an overview of the production history of The Last Emperor, focusing on the co-production collaborations and the outcomes of a western auteur’s gaze on Chinese history. Questions of Orientalism, travel narrative and critical reception are taken into account in order to engage with the transnational implications of Bertolucci’s film and the western fascination with China.
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We prove that the stable holonomies of a proper codimension 1 attractor Λ, for a Cr diffeomorphism f of a surface, are not C1+θ for θ greater than the Hausdorff dimension of the stable leaves of f intersected with Λ. To prove this result we show that there are no diffeomorphisms of surfaces, with a proper codimension 1 attractor, that are affine on a neighbourhood of the attractor and have affine stable holonomies on the attractor.
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The European Mouse Mutagenesis Consortium is the European initiative contributing to the international effort on functional annotation of the mouse genome. Its objectives are to establish and integrate mutagenesis platforms, gene expression resources, phenotyping units, storage and distribution centers and bioinformatics resources. The combined efforts will accelerate our understanding of gene function and of human health and disease.
Resumo:
Consumption values and different usage situations have received extensive interest from scholars; however, there is a lack of understanding regarding how these two constructs interact when it comes to the purchase decisions of consumers. This study examines the relationship between consumption values, consumption situations, and consumers’ purchasing decisions in terms of their willingness to pay and the purchase quantity. First of all, my model proposes that all four consumption values and different situations have a positive effect on consumers’ willingness to pay as well as the quantity they purchase. It also proposes that varying usage situations moderate the effect of consumption values on consumers’ purchasing decisions. In my conceptual model, I have also integrated the epistemic and conditional values where there is a gap in the existing literature. Prior literature has isolated the consumption values when studying how they affect consumer behavior and has not examined how consumption situations moderate the relationship between consumption values and purchasing decisions. Also, the existing literature has mostly focused on how consumption values affect purchase intentions, brand loyalty, or satisfaction, whereas my study focuses on purchasing decisions. For my study, the participants were randomly chosen from the general wine consumer population and the age range was between 20 and 75, which included 83 male respondents and 119 female respondents. The data received from my respondents support my hypotheses for the model. In my final chapter, I discuss the theoretical and managerial implications as well as suggestions for future research.
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This thesis examines the religious dimension of fandom in popular music, taking as an object of reflection Lady Gaga and her fans. I combine fan studies with theories of immanence as well as Deleuze and Guattari's notion of the process of becoming, and provide a theoretical reading of the relationship between Lady Gaga and her most fervent fans, the 'little monsters.' Both fandom and religion promise a stable sense of identity and authentic community to devotees. Performing deconstructive discourse analysis on three of Lady Gaga's music videos, I demonstrate how fandom, like organized religion, can simultaneously be an emancipatory practice and a practice that seeks to deny individual subjects their agency. This thesis provides a new theoretical framework for understanding fandom, and illustrates how the purported benefits of both fandom and religion can only be gained when the figureheads of each group are symbolically destroyed by the members themselves.
Resumo:
Contrairement à ce qui s’est produit dans les colonies espagnoles, en Nouvelle-Fance, les Français ont privilégié le maintien de relations pacifiques avec les peuples autochtones. Même si les représentants de la couronne sont autorisés à les assujettir par la force, très rapidement, le roi exige le respect des traités conclus avec eux. Ces alliances constituent d’ailleurs la première étape d’un processus de sédentarisation et de conversion qui doit, dans l’esprit des autorités, culminer par l’assujettissement des Autochtones à la couronne. Pour l’heure, au début du XVIIe siècle, ils sont considérés comme des alliés vivant selon leurs propres coutumes. C’est pourquoi Champlain doit renoncer à appliquer le droit français dans les cas où un Français a été tué par un Autochtone, alors qu’il n’envisage même pas d’imposer ces règles quand les protagonistes sont tous autochtones.
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La Conférence des Nations Unies sur l’environnement et le développement qui s’est tenue à Rio de Janeiro en juin 1992 a été, sans aucun doute, un événement marquant de la coopération multilatérale contemporaine. Le plus grand rassemblement multilatéral jamais organisé auparavant, cet événement aura marqué d’une empreinte indélébile l’architecture institutionnelle du traitement de la question envionnementale et façonne les institutions issues de la Conférence de Stockholm sur l’environnement humain. La Conférence de Rio aura été, au bout du compte, le point de départ d’une ère institutionelle nouvelle et d’une nouvelle façon d’aborder la coopération multilatérale pour la protection de l’environnement. La dimension institutionnelle de la question du développement durable renvoie nécessairement aux progrès qui restent à accomplir en vue d’une meilleure compréhension de la façon dont le développement durable est perçu au niveau national.Cette question traduit aussi la difficulté qu’il y a à adapter le mandat originel des institutions existantes aux exigences multiformes de l’intégration de la question de l’environnement dans les processus de développement économique et social.Elle exige surtout une action concertée tendue en vue d’une plus grande cohérence de l’action internationale qui serait au service d’une nouvelle démarche muliforme à l’égard de l’environnement,au service d’un développement respectueux des équilibres écologiques de notre planète.