1,030 research outputs found

    Probability, Evidential Support, and the Logic of Conditionals

    Get PDF
    Once upon a time, some thought that indicative conditionals could be effectively analyzed as material conditionals. Later on, an alternative theoretical construct has prevailed and received wide acceptance, namely, the conditional probability of the consequent given the antecedent. Partly following critical remarks recently ap- peared in the literature, we suggest that evidential support—rather than conditional probability alone—is key to understand indicative conditionals. There have been motivated concerns that a theory of evidential conditionals (unlike their more tra- ditional counterparts) cannot generate a sufficiently interesting logical system. Here, we will describe results dispelling these worries. Happily, and perhaps surprisingly, appropriate technical variations of Ernst Adams’s classical approach allow for the construction of a logic of evidential conditionals with distinctive fea- tures, which is also well-behaved and reasonably strong

    Photoluminescence transient study of surface defects in ZnO nanorods grown by chemical bath deposition

    Full text link
    Two deep level defects (2.25 and 2.03 eV) associated with oxygen vacancies (Vo_o) were identified in ZnO nanorods (NRs) grown by low cost chemical bath deposition. A transient behaviour in the photoluminescence (PL) intensity of the two Vo_o states was found to be sensitive to the ambient environment and to NR post-growth treatment. The largest transient was found in samples dried on a hot plate with a PL intensity decay time, in air only, of 23 and 80 s for the 2.25 and 2.03 eV peaks, respectively. Resistance measurements under UV exposure exhibited a transient behaviour in full agreement with the PL transient indicating a clear role of atmospheric O2_2 on the surface defect states. A model for surface defect transient behaviour due to band bending with respect to the Fermi level is proposed. The results have implications for a variety of sensing and photovoltaic applications of ZnO NRs

    The role of radiation damping in the modeling of repeated earthquake events

    Get PDF
    We have investigated the role of the radiation damping term (RDT) on repeated earthquake ruptures by modeling the faulting process through a single one-dimensional analog fault system governed by different constitutive laws. The RDT expresses the energy lost by the seismic waves. The RDT is inherently accounted for in more elaborated, fully dynamic models of extended fault, whereas it is neglected in one-dimensional fault models. In this study, we adopt various formulations of the laboratoryderived rate-dependent and state-dependent friction constitutive laws: the Dieterich-Ruina law, the Ruina-Dieterich law and the Chester and Higgs law. Our numerical results clearly indicate that the RDT significantly affects the system dynamics. More specifically, the more the RDT is effective, the more frequent the slip failures are (with a cycle-time reduction of ca. 30%). We also show that inclusion of the RDT tends to promote smaller but more frequent earthquake instabilities, irrespective of the choice of the governing law. Our data shed light on the limitations implied by the conventional formulation of the equation of motion for the spring system, in which the energy radiation is ignored

    A new methodology to model interdependency of Critical Infrastructure Systems during Hurricane Sandy’s event

    Get PDF
    The paper proposes a methodology to evaluate the resilience of the critical infrastructures networks hit by Hurricane Sandy in October 2012. The region analyzed in the case study is New York metropolitan area which includes New York City and the nearby state of New Jersey. This region was the most affected by the storm and it is one of the most densely populated regions of the United States due to its high concentration of businesses and several critical infrastructures. The identified critical infrastructure systems are highly interconnected, forming a heterogeneous network that is very vulnerable to catastrophic events, such as hurricanes. Due to several existing interdependencies, the systems are subjected to disruptive cascading effects. The disruption of one or more of these systems directly affects people, businesses, the government and leads to additional indirect damages. After a critical comparison of the different methodologies to analyze infrastructure interdependency, the input-output method is selected in order to indentify and rank the different types of dependencies in the network as well as to prioritize the different actions during the restoration process. Previous analyses have shown that power, transportation, and fuel were the most damaged networks in the region generating severe cascading effects due to the interdependencies between them. A series of recommendations to improve the global resilience in the region are provided which will be able to prevent cascading effects and prioritize the recovery effort in the future

    A new methodology to model interdependency of Critical Infrastructure Systems during Hurricane Sandy’s event

    Get PDF
    The paper proposes a methodology to evaluate the resilience of the critical infrastructures networks hit by Hurricane Sandy in October 2012. The region analyzed in the case study is New York metropolitan area which includes New York City and the nearby state of New Jersey. This region was the most affected by the storm and it is one of the most densely populated regions of the United States due to its high concentration of businesses and several critical infrastructures. The identified critical infrastructure systems are highly interconnected, forming a heterogeneous network that is very vulnerable to catastrophic events, such as hurricanes. Due to several existing interdependencies, the systems are subjected to disruptive cascading effects. The disruption of one or more of these systems directly affects people, businesses, the government and leads to additional indirect damages. After a critical comparison of the different methodologies to analyze infrastructure interdependency, the input-output method is selected in order to indentify and rank the different types of dependencies in the network as well as to prioritize the different actions during the restoration process. Previous analyses have shown that power, transportation, and fuel were the most damaged networks in the region generating severe cascading effects due to the interdependencies between them. A series of recommendations to improve the global resilience in the region are provided which will be able to prevent cascading effects and prioritize the recovery effort in the future

    ‘Malvasia nera di Brindisi/Lecce’ grapevine cultivar (Vitis vinifera L.) originated from ‘Negroamaro’ and ‘Malvasia bianca lunga’

    Get PDF
    ‘Malvasia nera di Brindisi’ and ‘Malvasia nera di Lecce’ are two of the few Malvasias with black berries and belong to the Apulian ampelographic assortment (South Italy). Their presumed synonymy has been recently ascertained with SSR markers and therefore these two black 'Malvasias' can be considered as an unique variety. We discovered that this cultivar is the cross between ‘Malvasia bianca lunga’ alias ‘Malvasia del Chianti’ and ‘Negroamaro’ by using 42 nuclear SSR. Both parents belong to the Apulian varietal resources, since centuries. So far, ‘Malvasia nera di Brindisi/Lecce’ origin has been obscure; now we may assert that this cultivar was born right in Apulia. Three sets of chloroplast SSR loci were used to determine the female and the male parent: 6 ccmp loci, already used in previous pedigree studies, 15 ccSSR loci and 2 NTCP loci, derived from tobacco. The second set of loci was sequenced in order to compare the length of the markers with the reference species where they were originally obtained: in 4 cases no microsatellite motives were detected and in other 4 cases the perfect repetition found in tobacco was not maintained in grape. Unfortunately, the three sets of markers failed to show any polymorphism. A detailed comparison of the black Malvasia morphology with its two parents showed a closer similarity to ‘Negroamaro’. Also the anthocyanin profile is in agreement with that of the black parent; its varietal aroma presents interesting levels of free and bound 2-phenylethanol, responsible for rose flavor, and of bound linalool compounds.
    • …
    corecore