15,301 research outputs found

    Generic method for bijections between blossoming trees and planar maps

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    This article presents a unified bijective scheme between planar maps and blossoming trees, where a blossoming tree is defined as a spanning tree of the map decorated with some dangling half-edges that enable to reconstruct its faces. Our method generalizes a previous construction of Bernardi by loosening its conditions of applications so as to include annular maps, that is maps embedded in the plane with a root face different from the outer face. The bijective construction presented here relies deeply on the theory of \alpha-orientations introduced by Felsner, and in particular on the existence of minimal and accessible orientations. Since most of the families of maps can be characterized by such orientations, our generic bijective method is proved to capture as special cases all previously known bijections involving blossoming trees: for example Eulerian maps, m-Eulerian maps, non separable maps and simple triangulations and quadrangulations of a k-gon. Moreover, it also permits to obtain new bijective constructions for bipolar orientations and d-angulations of girth d of a k-gon. As for applications, each specialization of the construction translates into enumerative by-products, either via a closed formula or via a recursive computational scheme. Besides, for every family of maps described in the paper, the construction can be implemented in linear time. It yields thus an effective way to encode and generate planar maps. In a recent work, Bernardi and Fusy introduced another unified bijective scheme, we adopt here a different strategy which allows us to capture different bijections. These two approaches should be seen as two complementary ways of unifying bijections between planar maps and decorated trees.Comment: 45 pages, comments welcom

    Prokofiev’s “Romeo and Juliet” and Socialist Realism: a Case-Study in Intersemiotic Translation

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    This paper is concerned with Prokofiev’s ballet score, Romeo and Juliet, as an inter-semiotic translation of Shakespeare’s play. My aim is to consider Prokofiev’s distinct interpretation of the play in the light of the political climate of the Soviet Union in the 1930s and to attempt to determine the extent to which it conforms to the norms of Socialist Realism. This is by no means an easy matter, for the composer was at different times lauded by the authorities and vilified by them, while the work itself has been appropriated by both sides of the ideological divide. Nevertheless, close examination of the musical discourse reveals important alterations to Shakespeare’s original concept, shedding some light upon the composer’s own ideology and consequently upon his relationship to the regime under which he lived

    Assessing the potential for U.S. utility green bonds

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    EXECUTIVE SUMMARY: Bonds are the largest single class of financial instrument across the world’s financial markets. Recently, a subclass of these bonds, called green bonds, has emerged in the market place. Green bonds are a type of bond whose proceeds may be used only for certain approved “green” investments. In exchange for agreeing to invest only in such projects, the bond issuer obtains some value greater than they would obtain from traditional financing, and are therefore encouraged to finance and undertake a greater number of green projects. This unique value may not be recognized in traditional financial accounting. Of course, like any other capital-raising investment, green bonds enable their issuer to finance a new project that should increase (or at least maintain) its revenues, profits, and cash flow. The utility sector was the second largest issuer of green bonds in 2017, accounting for $26.2 billion dollars’ worth of green bond issuance globally. These were primarily issued to finance renewable energy projects, a class of projects that makes the utility sector one of the most logical for deployment of green bonds. While choosing to issue green bonds does not seem to have any price advantage over regular bonds in the market, green bonds can provide other benefits. These benefits may include reputation effects, better treatment in secondary markets, and other intangibles (See Table ES1)

    Analysis of parametric biological models with non-linear dynamics

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    In this paper we present recent results on parametric analysis of biological models. The underlying method is based on the algorithms for computing trajectory sets of hybrid systems with polynomial dynamics. The method is then applied to two case studies of biological systems: one is a cardiac cell model for studying the conditions for cardiac abnormalities, and the second is a model of insect nest-site choice.Comment: In Proceedings HSB 2012, arXiv:1208.315

    Do Monetary Incentives and Chained Questions Affect the Validity of Risk Estimates Elicited via the Exchangeability Method? An Experimental Investigation

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    Using a laboratory experiment, we investigate the validity of stated risks elicited via the Exchangeability Method (EM) by defining a valuation method based on de Finetti’s notion of coherence. The reliability of risk estimates elicited through the EM has been theoretically questioned because the chained structure of the game, in which each question depends on the respondent’s answer to the previous one, is thought to potentially undermine the incentive compatibility of the elicitation mechanism even when real monetary incentives are provided. Our results suggest that superiority of real monetary incentives is not evident when people are presented with chained experimental designlab experiment, risk elicitation, exchangeability, validity, pesticide residue
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