Improved decision for a resource-efficient fusion scheme in cooperative spectrum sensing

Paper presented at at 2015 International Workshop on Telecommunications (IWT), 14th to 17th of June, Santa Rita do Sapucai, Brazil. Abstract Recently, a novel decision fusion scheme for cooperative spectrum sensing was proposed, aiming at saving resources in the reporting channel transmissions. Secondary users are allowed to report their local decisions through the symbols of binary modulations, at the same time and with the same carrier frequencies. As a consequence, the transmitted symbols add incoherently at the fusion center, forming a larger set of symbols in which a subset is associated to the presence of the primary signal, and another subset is associated to the absence of such a signal. A Bayesian decision criterion with uniform prior was applied for discriminating these subsets. In this paper we propose a modified decision rule in which the target probabilities of detection and false alarm are taken into account to produce a large performance improvement over the original decision criterion. This improvement comes with practically no cost in complexity and does not demand the knowledge of any additional information when compared to the original rule

Desenvolvimento de bezerros desmamados pastejando caatinga e capim buffel e suplementados com feno de leucena.

O objetivo do trabalho foi avaliar um sistema alternativo de suplementacao da alimentacao de bovinos, delineado para antecipar a idade media ao abate de 40-60 meses observada na regiao semi-arida do Nordeste. Para isto, avaliou-se o ganho de peso de 45 bezerros anelorados, desmamados, distribuidos em tres grupos: (C) patejo exclusivo em caatinga durante todo o ano; (B) pastejo em caatinga, no periodo verde, e em capim buffel (Cenchrus ciliaris L.) no periodo seco; (CBL) o mesmo que CB mais suplementacao com feno de leucena (Leucaena leucocephala (Lam.) de Wit.), no periodo seco. As observacoes foram feitas durante dois periodos secos e dois chuvosos, num total de 711 dias. Ao final do periodo experimental, os animais do grupo suplementado com leucena estavam em media, 33,4 Kg e 107,5 Kg mais pesados (P < 0,05) que os dos grupos CB e C, respectivamente. Os resultados indicam que mesmo com uma oferta quantitativamente inaqueada de leucena foi possivel a obtencao de animais com o mesmo peso medio ao abate observado na regiao, com, pelo menos, 14 meses de antecipacao

Remarks on some vacuum solutions of scalar-tensor cosmological models

We present a class of exact vacuum solutions corresponding to de Sitter and warm inflation models in the framework of scalar-tensor cosmologies. We show that in both cases the field equations reduce to planar dynamical systems with constraints. Then, we carry out a qualitative analysis of the models by examining the phase diagrams of the solutions near the equilibrium points.Comment: 12 pages, 4 figures. To be published in the Brazilian Journal of Physic

Brand Community, Loyalty and Promise in myfootballclub.co.uk

Purpose The primary purpose of this paper is to link the notions of brand community, loyalty and promise as a reminder to marketers of the importance to brands of keeping their commercial promises to brand community members. Design/methodology/approach The paper reports on a questionnaire survey (n=500) of members of a sport brand community as part of an investigation into the relationship between brand community and brand loyalty. Findings Brand loyalty was predicted by age, frequency of attendance, motivations for joining the brand community and the degree to which expectations built by the brand promise are met. Research limitations/implications In common with many inquiries in the area of brand community, this is a single case study. It is primarily a cross-sectional study, with a minor longitudinal element. Practical implications Branding practitioners and consultants with responsibility for brand community management issues need to balance the consumer-to-consumer dimensions of community with a careful understanding and operationalisation of the brand promise. Originality/value (mandatory): This is the first paper to integrate the constructs of brand community and brand loyalty with that of brand promise