7 research outputs found

    Generating fuzzy rules by learning from olive tree transpiration measurement - An algorithm to automatize Granier sap flow data analysis

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    The present study aims at developing an intelligent system of automating data analysis and prediction embedded in a fuzzy logic algorithm (FAUSY) to capture the relationship between environmental variables and sap flow measurements (Granier method). Environmental thermal gradients often interfere with Granier sap flow measurements since this method uses heat as a tracer, thus introducing a bias in transpiration flux calculation. The FAUSY algorithm is applied to solve measurement problems and provides an approximate and yet effective way of finding the relationship between the environmental variables and the natural temperature gradient (NTG), which is too complex or too ill-defined for precise mathematical analysis. In the process, FAUSY extracts the relationships from a set of input–output environmental observations, thus general directions for algorithm-based machine learning in fuzzy systems are outlined. Through an iterative procedure, the algorithm plays with the learning or forecasting via a simulated model. After a series of error control iterations, the outcome of the algorithm may become highly refined and be able to evolve into a more formal structure of rules, facilitating the automation of Granier sap flow data analysis. The system presented herein simulates the occurrence of NTG with reasonable accuracy, with an average residual error of 2.53% for sap flux rate, when compared to data processing performed in the usual way. For practical applications, this is an acceptable margin of error given that FAUSY could correct NTG errors up to an average of 76% of the normal manual correction process. In this sense, FAUSY provides a powerful and flexible way of establishing the relationships between the environment and NTG occurrencesinfo:eu-repo/semantics/publishedVersio

    A multi-country level analysis of the environmental attitudes and behaviours among young consumers

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    Environmental issues have become more prominent internationally and are increasingly featured in discussion by governments, business and academics. This paper presents the results of a study which examines the concerns for environmental issues and purchase behaviours of a sample of 1173 young consumers in England, Germany, Portugal and Spain; countries which represent different realities in terms of economic development, social context and cultural issues. An analysis of the differences between the respondents from the four countries regarding concepts such as man-nature orientation, generativity, environmental concern, consumer perceived effectiveness, conservation behaviour and environmentally-friendly buying behaviour is presented. The results obtained confirm the existence of significant differences between countries for almost all variables. © 2013 Copyright Taylor and Francis Group, LLC

    Global Monitor Entrepreneurship Monito - Relatório Executivo 2014/15 EUROACE

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    Neste estudo analisa-se a situação da atividade empreendedora na EUROREGIÃO EUROACE, que inclui em Portugal o Alentejo e o Centro e em Espanha a Extremadura. As dimensões analisadas compreendem a atividade empreendedora e as suas caraterísticas, os valores, perceções e atitudes empreendedoras, aspirações da atividade empreendedora e o ambiente empreendedor na EUROACE. Os resultados levam a concluir que o ecossistema empreendedor da EUROREGIÃO EUROACE apresenta ainda debilidades importantes face à média dos países europeus cujas economias são baseadas na inovação. Entre as debilidades que deverão ser melhoradas encontram-se as infraestruturas físicas e comerciais, a abertura dos mercados, o apoio ao financiamento das empresas e as políticas governamentais.Foundación Xavier Sala
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