1,731 research outputs found

    Perspectivar o pensamento do design

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    presente estudo visa contribuir para uma perspectivação do design thinking, que assume cada vez mais importância no mundo do design e em áreas externas ao design. Pretendemos acentuar a relevância da adopção do design thinking como forma de beneficiar e melhorar os processos criativos no seio das organizações. O artigo divide-se em quatro partes: a complexidade da experiência humana, o peso do valor acrescentado no pensamento do design, os cinco modos propostos pela Universidade de Stanford para o pensamento do design e, finalmente, a apologia do movimento colaborativo. Neste contexto, terá especial destaque, em vários níveis, a relevância da interdisciplinaridade na resolução de problemas

    How to Find Suitable Ontologies Using an Ontology-based WWW Broker

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    Knowledge reuse by means of outologies now faces three important problems: (1) there are no standardized identifying features that characterize ontologies from the user point of view; (2) there are no web sites using the same logical organization, presenting relevant information about ontologies; and (3) the search for appropriate ontologies is hard, time-consuming and usually fruitless. To solve the above problems, we present: (1) a living set of features that allow us to characterize ontologies from the user point of view and have the same logical organization; (2) a living domain ontology about ontologies (called ReferenceOntology) that gathers, describes and has links to existing ontologies; and (3) (ONTO)2Agent, the ontology-based www broker about ontologies that uses the Reference Ontology as a source of its knowledge and retrieves descriptions of ontologies that satisfy a given set of constraints. (ONTO)~Agent is available at http://delicias.dia.fi.upm.es/REFERENCE ONTOLOGY

    Reference Ontology and (ONTO)2 Agent: The Ontology Yellow pages

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    Knowledge reuse by means of ontologies faces three important problems at present: (1) there are no standardized identifying features that characterize ontologies from the user point of view; (2) there are no web sites using the same logical organization, presenting relevant information about ontologies; and (3) the search for appropriate ontologies is hard, time-consuming and usually fruitless. To solve the above problems, we present: (1) a living set of features that allow us to characterize ontologies from the user point of view and have the same logical organization; (2) a living domain ontology about ontologies (called Reference Ontology) that gathers, describes and has links to existing ontologies; and (3) (ONTO)2Agent, the ontology-based WWW broker about ontologies that uses Reference Ontology as a source of its knowledge and retrieves descriptions of ontologies that satisfy a given set of constraints

    The Phase Diagrams of the Schwinger and Gross-Neveu Models with Wilson Fermions

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    A new method to analytically determine the partition function zeroes of weakly coupled theories on finite-size lattices is developed. Applied to the lattice Schwinger model, this reveals the possible absence of a phase transition at fixed weak coupling. We show how finite-size scaling techniques on small or moderate lattice sizes may mimic the presence of a spurious phase transition. Application of our method to the Gross-Neveu model yields a phase diagram consistent with that coming from a saddle point analysis.Comment: Talk at LATTICE99, 3 pages, 2 figure

    Lusitania

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    The present study attempts to illustrate the large phytocoenotical diversity of forests, pre-forest, high-scrub and most of the corresponding sub-seral communities of the Lusitania territories and enables the identification of their clumped pattern of occurrence as landscape mosaics. These communities are syntaxonomically included in the Quercetea ilicis, Querco-Fagetea sylvaticae, Salici purpureae-Populetea nigrae, Alnetea glutinosae, Nerio-Tamaricetea, Calluno vulgaris-Ulicetea minoris, Cisto-Lavanduletea stoechadis and Rosmarinetea officinalis vegetation classes and span a large spectrum of environmental variables, being present in a wide range of bioclimatic stages and edaphic conditions. The grasslands, that represent seral stages of the Quercion broteroi and Quercion pyrenaicae and are included in the Stipo giganteae-Agrostietea castellanae class, are also described. In Lusitania, on soils rich in bases, without hydromorphy and salinity, dry grasslands are widespread in the potential areas of Quercus suber, Q. rotundifolia and/or Q. faginea, and are included in the Festuco-Brometea vegetation class; associations of the Arrábida mountain and Algarve are especially rich in endemic species. The ephemeral pioneer communities are dominated by non-nitrophilous, small therophytes included in the Helianthemetea guttati class. Grasslands linked to heavy grazing are also described. In this group we include pastures, with adequate sheep pasture, grazed and manured, dominated by dwarf perennial grasses and other nutritious prostrate chamaephytes and hemicryptophytes, which encompass the associations of the Poetea bulbosae class. Other herbaceous communities, dependent on anthropic influence, are those dense meadows and reed-beds included in the Molinio-Arrhenatheretea class.The tall herbs of nitrified wood fringes and other semi-shaded anthropic biotope communities belong to the Galio-Urticetea class. The herbaceous ruderal vegetation is also described. Lastly, the coastal vegetation of sea cliffs and lithosols, dunes, and estuaries and saltmarshes is referred to, as well as the interior sandy soil or semi-fixed dune grasslands

    Long Range Anticorrelations and Non-Gaussian Behavior of a Leaky Faucet

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    We find that intervals between successive drops from a leaky faucet display scale-invariant, long-range anticorrelations characterized by the same exponents of heart beat-to-beat intervals of healthy subjects. This behavior is also confirmed by numerical simulations on lattice and it is faucet-width- and flow-rate-independent. The histogram for the drop intervals is also well described by a L\'evy distribution with the same index for both histograms of healthy and diseased subjects. This additional result corroborates the evidence for similarities between leaky faucets and healthy hearts underlying dynamics.Comment: Self-extracting uuencoded postscript file. Phys.Rev.E (Rap.Comm.). Related papers can be found at http://www.if.uff.br/~tjpp/tjppe.htm

    Higher Order Evaluation of the Critical Temperature for Interacting Homogeneous Dilute Bose Gases

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    We use the nonperturbative linear \delta expansion method to evaluate analytically the coefficients c_1 and c_2^{\prime \prime} which appear in the expansion for the transition temperature for a dilute, homogeneous, three dimensional Bose gas given by T_c= T_0 \{1 + c_1 a n^{1/3} + [ c_2^{\prime} \ln(a n^{1/3}) +c_2^{\prime \prime} ] a^2 n^{2/3} + {\cal O} (a^3 n)\}, where T_0 is the result for an ideal gas, a is the s-wave scattering length and n is the number density. In a previous work the same method has been used to evaluate c_1 to order-\delta^2 with the result c_1= 3.06. Here, we push the calculation to the next two orders obtaining c_1=2.45 at order-\delta^3 and c_1=1.48 at order-\delta^4. Analysing the topology of the graphs involved we discuss how our results relate to other nonperturbative analytical methods such as the self-consistent resummation and the 1/N approximations. At the same orders we obtain c_2^{\prime\prime}=101.4, c_2^{\prime \prime}=98.2 and c_2^{\prime \prime}=82.9. Our analytical results seem to support the recent Monte Carlo estimates c_1=1.32 \pm 0.02 and c_2^{\prime \prime}= 75.7 \pm 0.4.Comment: 29 pages, 3 eps figures. Minor changes, one reference added. Version in press Physical Review A (2002

    Classical analogous of quantum cosmological perfect fluid models

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    Quantization in the mini-superspace of a gravity system coupled to a perfect fluid, leads to a solvable model which implies singularity free solutions through the construction of a superposition of the wavefunctions. We show that such models are equivalent to a classical system where, besides the perfect fluid, a repulsive fluid with an equation of state pQ=ρQp_Q = \rho_Q is present. This leads to speculate on the true nature of this quantization procedure. A perturbative analysis of the classical system reveals the condition for the stability of the classical system in terms of the existence of an anti-gravity phase.Comment: Latex file, 10 pages, 3 figure

    The discontinuous nature of chromospheric activity evolution

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    Chromospheric activity has been thought to decay smoothly with time and, hence, to be a viable age indicator. Measurements in solar type stars in open clusters seem to point to a different conclusion: chromospheric activity undergoes a fast transition from Hyades level to that of the Sun after about 1 Gyr of main--sequence lifetime and any decaying trend before or after this transition must be much less significant than the short term variations.Comment: 6 pages, 1 figure, to be published in Astrophysics and Space Scienc
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