33,928 research outputs found

    A new family of maximal curves

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    In this article we construct for any prime power qq and odd n≄5n \ge 5, a new Fq2n\mathbb{F}_{q^{2n}}-maximal curve Xn\mathcal X_n. Like the Garcia--G\" uneri--Stichtenoth maximal curves, our curves generalize the Giulietti--Korchm\'aros maximal curve, though in a different way. We compute the full automorphism group of Xn\mathcal X_n, yielding that it has precisely q(q2−1)(qn+1)q(q^2-1)(q^n+1) automorphisms. Further, we show that unless q=2q=2, the curve Xn\mathcal{X}_n is not a Galois subcover of the Hermitian curve. Finally, we find new values of the genus spectrum of Fq2n\mathbb{F}_{q^{2n}}-maximal curves, by considering some Galois subcovers of Xn\mathcal X_n

    Weierstrass semigroups on the Giulietti-Korchm\'aros curve

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    In this article we explicitly determine the structure of the Weierstrass semigroups H(P)H(P) for any point PP of the Giulietti-Korchm\'aros curve X\mathcal{X}. We show that as the point varies, exactly three possibilities arise: One for the Fq2\mathbb{F}_{q^2}-rational points (already known in the literature), one for the Fq6∖Fq2\mathbb{F}_{q^6} \setminus \mathbb{F}_{q^2}-rational points, and one for all remaining points. As a result, we prove a conjecture concerning the structure of H(P)H(P) in case PP is an Fq6∖Fq2\mathbb{F}_{q^6} \setminus \mathbb{F}_{q^2}-rational point. As a corollary we also obtain that the set of Weierstrass points of X\mathcal{X} is exactly its set of Fq6\mathbb{F}_{q^6}-rational points

    Muintir na Tire Seeks Funding for Rural Sociology in 1960s Ireland

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    working paperMuintir na Tire’s role in the emergence of the discipline of Sociology in Ireland is usually acknowledged with reference to the Limerick Rural Survey (1958-64) that it initiated, part-funded and published. In the first half of the 1960s the movement also put proposals to the Irish government and sought US foundation grants for a centre or institute that would operate in the field of rural sociology and form part of Muintir na Tire’s organisational structure. Although Taoiseach Sean Lemass was positively disposed towards these initatives, opposition from the Departments of Agriculture, Education and Finance prevailed against them and Muintir na Tire was ultimately to find itself completely excluded from participation in the state-resourced institutional arrangements for carrying out social/sociological research in Ireland

    Heat maximal function on a Lie group of exponential growth

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    Let G be the Lie group R^2\rtimes R^+ endowed with the Riemannian symmetric space structure. Let X_0, X_1, X_2 be a distinguished basis of left-invariant vector fields of the Lie algebra of G and define the Laplacian \Delta=-(X_0^2+X_1^2+X_2^2). In this paper, we show that the maximal function associated with the heat kernel of the Laplacian \Delta is bounded from the Hardy space H^1 to L^1. We also prove that the heat maximal function does not provide a maximal characterization of the Hardy space H^1.Comment: 18 page

    Boundedness from H^1 to L^1 of Riesz transforms on a Lie group of exponential growth

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    Let GG be the Lie group given by the semidirect product of R2R^2 and R+R^+ endowed with the Riemannian symmetric space structure. Let X0,X1,X2X_0, X_1, X_2 be a distinguished basis of left-invariant vector fields of the Lie algebra of GG and define the Laplacian Δ=−(X02+X12+X22)\Delta=-(X_0^2+X_1^2+X_2^2). In this paper we consider the first order Riesz transforms Ri=XiΔ−1/2R_i=X_i\Delta^{-1/2} and Si=Δ−1/2XiS_i=\Delta^{-1/2}X_i, for i=0,1,2i=0,1,2. We prove that the operators RiR_i, but not the SiS_i, are bounded from the Hardy space H1H^1 to L1L^1. We also show that the second order Riesz transforms Tij=XiΔ−1XjT_{ij}=X_i\Delta^{-1}X_j are bounded from H1H^1 to L1L^1, while the Riesz transforms Sij=Δ−1XiXjS_{ij}=\Delta^{-1}X_iX_j and Rij=XiXjΔ−1R_{ij}=X_iX_j\Delta^{-1} are not.Comment: This paper will be published in the "Annales de l'Institut Fourier

    Public Perception of Risk Management in Environmental Controversies: A U.K. Case Study

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    Drs. Simosi and Allen focus on issues arising from an environmental dispute in the U.K. Their case study findings are discussed in the context of existing environmental decision-making procedures in the U.K

    Measuring group switching in the European Parliament: Methodology, data and trends (1979-2009)

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    Party group switching in the European Parliament (ep), where parliamentarians individually or collectively switch from one party group to the other, is a well-known contributor to the volatility of the ep party system. We present a new dataset that contains party group information on all meps from 1979 to 2009. As a first step to a more comprehensive analysis of the phenomenon of party group switching in the ep we describe characteristics of all switches that have occurred in these six legislatures, with a focus on the trends across time, variety between member states, party groups, and ideological party families
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