141 research outputs found
Two formalisms of extended possibilistic logic programming with context-dependent fuzzy unification A comparative description
AbstractPossibilistic logic is a logic of uncertainty where a certainty degree between 0 and 1, interpreted as a lower bound of a necessity measure, is attached to each classical formula. In this paper we present a comparative description of two models extending first order possibilistic logic so as to allow for fuzzy unification. The first formalism, called PLFC, is a general extension that allows clauses with fuzzy constants and fuzzily restricted quantifiers. The second formalism is an implication-based extension defined on top of Gödel infinitely-valued logic, capable of dealing with fuzzy constants. In this paper we compare these approaches, mainly their Horn-clause fragments, discussing their basic differences, specially in what regards their unification and automated deduction mechanisms
Games on Cellular Spaces: How Mobility Affects Equilibrium
In this work we propose a new model for spatial games. We present a definition of mobility in terms of the satisfaction an agent has with its spatial location. Agents compete for space through a non-cooperative game by using mixed strategies. We are particularly interested in studyig the relation between Nash equilibrium and the winner strategy of a given model with mobility, and how the mobility can affect the results. The experiments show that mobility is an important variable concerning spatial games. When we change parameters that affect mobility, it may lead to the success of strategies away from Nash equilibrium.Spatial Games, Agent-Based Modelling, Mobility, Satisfaction, Chicken Game, Nash Equilibrium
A REPRESENTAÇÃO FONOLÓGICA DA VIBRANTE NO PORTUGUÊS BRASILEIRO
Neste estudo, o status fonológico da vibrante é discutido com base nas teorias estruturalista, gerativista e sociolinguÃstica. A maioria dos estruturalistas confirma a existência de dois fonemas, a vibrante forte e a fraca; já os gerativistas defendem a existência de um só fonema vibrante. Para Câmara Jr. (1953) e Abaurre e Sandalo (2003) é a vibrante forte, para Lopez (1979) e Monaretto (1997) é a vibrante fraca. Muitos Ãtalo-brasileiros interpretam o tepe [ɾ] e a múltipla [Å™] como sendo parte da mesma unidade fonológica (MONARETTO, 1997). Pressupõem-se a existência da vibrante múltipla [Å™] na estrutura subjacente do português brasileiro, pois permite derivar todas as formas variantes de maneira simples, natural e com poder de previsão (ABAURRE; SANDALO, 2003).
Análise de Experimentos de QuÃmica Orgânica sob uma Perspectiva de QuÃmica Verde
Este trabalho apresenta a análise de verdura quÃmica de experimentos realizados nas aulas experimentais de QuÃmica Orgânica no ensino superior. Para realização dessas análises empregou-se as métricas Matriz Verde, uma métrica qualitativa, e Estrela Verde, uma métrica semi-quantitativa que mostra graficamente o atendimento dos princÃpios da QuÃmica Verde. Foram analisados 03 (três) propostas experimentais realizadas nas aulas de QuÃmica Orgânica Experimental no curso de QuÃmica do IFPR – Campus Palmas (Experimentos A) e comparou-se com experimentos correlatos, proposto por Pavia et al (2009) (Experimentos B). Os resultados demonstram que os Experimentos A apresentam maiores Ãndice de verdura quando comparados com os experimentos B, no entanto ambos os protocolos experimentais analisados apresentam possibilidades de melhoria do ponto de vista da QuÃmica Verde. A utilização da Matriz Verde e Estrela Verde mostrou ser uma importante ferramenta para disseminar o conhecimento da QuÃmica Verde, bem como, demonstrar para o acadêmico a importância de conhecer suas práticas e os possÃveis resultados negativos que as mesmas podem trazer.
Evaluation of the Biotechnological Potential of Monteverdia salicifolia (Mart ex. Reissek) Biral
Plant extracts are a good alternative of reducing agents in the synthesis of metal nanoparticles. In this paper, we report the evaluation of the cytotoxic activity against T3 cell lines of the ethanolic extract of Monteverdia salicifolia (Mart ex. Reissek) Biral roots (MS) as well as a green one-pot route of synthesis of silver nanoparticles (AgNPs) using that extract as reducing and stabilizing agent. The extract exhibited dose dependent activity. The smallest particle size (48.01 nm) was achieved in just 25 minutes by employing a temperature of 65 °C and AgNO3 and MS concentrations equal to 0.9 mmol.L−1 and 0.67 mg.mL−1, respectively. The AgNPs-MS nanocomposite was characterized by UV–vis spectroscopy, FEG microscope and zeta potential, which proved that MS was effective at reducing and capping the AgNPs. In order to emphasize the advantage of the methodology applied in this synthesis, it was compared to a usual procedure using NaBH4 as a reducing agent and the greenness analysis was also carried out, using the Green Star.
DOI: http://dx.doi.org/10.17807/orbital.v13i2.154
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