19,554 research outputs found

    Light element abundances in He-rich stars

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    We present an abundance analysis of light elements in He-rich stars. The analysis is based on both low and high resolution observations collected at ESO, La Silla, Chile in the optical region and includes 6 standards and 21 He-rich stars. Light-element abundances display a diverse pattern: they range from under-solar up to above-solar values.Comment: 4 pages, no figure, to appear in: Proc. of the 26th workshop of the European Working Group on CP stars, eds. P. North, A. Schnell and J. Ziznovsky, Contrib. Astr. Obs. Skalnate Pleso Vol. 27, No

    DATA AND MODELS FOR EFFECTIVE RESEARCH AND DEVELOPMENT IN POLLUTION CONTROL

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    Environmental Economics and Policy,

    The evolutionary state and fundamental parameters of metallic A-F giants

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    Using Hipparcos parallaxes, we show that the metallic A-F giants found by Hauck (1986) on the basis of their high Delta m_2 index in Geneva photometry are on average more evolved than their non-metallic counterparts. Their mass distribution, rate of binaries and vsini are shown to be incompatible with those of Am stars, so that they cannot be descendants of the latter. They might be former normal stars going through a short metal-rich phase at the very end of their life on the Main Sequence.Comment: 3 pages, 1 figure, to appear in: Proc. of the 26th workshop of the European Working Group on CP stars, eds. P. North, A. Schnell and J. Ziznovsky, Contrib. Astr. Obs. Skalnate Pleso Vol. 27, No

    Evolution of magnetic fields in stars across the upper main sequence

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    To properly understand the physics of upper main sequence stars it is particularly important to identify the origin of their magnetic fields. Recently, we confirmed that magnetic fields appear in Ap stars of mass below 3 M_sun only if they have already completed at least approximately 30% of their main-sequence lifetime. The absence of stars with strong magnetic fields close to the ZAMS might be seen as an argument against the fossil field theories. Here we present the results of our recent magnetic survey with FORS1 at the VLT in polarimetric mode of a sample of A, B and Herbig Ae stars with previously undetected magnetic fields and briefly discuss their significance for our understanding of the origin of the magnetic fields in intermediate mass stars.Comment: 6 pages, 3 figures, to appear in "Magnetic Fields in the Universe: From Laboratory and Stars to Primordial Structures", AIP Conference Proceedings 78

    UD Annotatrix: An Annotation Tool For Universal Dependencies

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    In this paper we introduce the UD Annotatrix annotation tool for manual annotation of Universal Dependencies. This tool has been designed with the aim that it should be tailored to the needs of the Universal Dependencies (UD) community, including that it should operate in fully-offline mode, and is freely-available under the GNU GPL licence. In this paper, we provide some background to the tool, an overview of its development, and background on how it works. We compare it with some other widely-used tools which are used for Universal Dependencies annotation, describe some features unique to UD Annotatrix, and finally outline some avenues for future work and provide a few concluding remarks

    Probabilistic models of planetary contamination

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    Likely fundamental inadequacies in the model of planetary contamination advanced by Sagan and Coleman are discussed. It is shown that a relatively minor modification of the basic Sagan-Coleman formula yields approximations that are generally adequate with data in the range of interest. This approximation formula differs from the original Sagan-Coleman version only through an initial conditioning on landing outcome. It always yields an upper (conservative) bound for the total probability of contamination, this appealing feature is lost if the conditioning on landing outcome is deleted

    Immersive Visualization Environments for Teaching/Learning

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    Comparative Study of Brain Activities in Immersive Visualization Environments: An Innovative Pedagogical Technique Abstract The primary objective of this work-in-progress is to investigate advanced and innovative pedagogical techniques in teaching and learning STEM concepts by utilizing Immersive Visualization Environments (IVE). Specifically, a comparative study of brain activities was performed to determine effectiveness of different Immersive Visualization Environments in pedagogy. Twelve randomly selected college students participated in this investigation using an electroencephalography (EEG) device for measuring brain waves of the subjects. The preliminary collected data supported the assertion that dome-shaped IVE elicited a more relaxed state than its counterpart, head-mounted IVE, yielding a higher performance. Audience: College/University Professors Conference Track: R1 - Work-in-progress Format of Presentation: Poster Session Participants\u27 Engagement: N/A Participants\u27 Gain: Exposure and Knowledge of Immersive Visualization Environment for Teaching/Learning in STEM fields. Alignment: Objectives of this poster session is directly aligned with the objectives of the conference

    Introduction to the Douglass C. North Memorial Issue

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    This is the accepted version of the following article: Geoffrey M. Hodgson, ‘Introduction to the Douglass C. North memorial issue’, Journal of Institutional Economics, (early view) 1 December 2016, which has been published in final form at DOI: https://doi.org/10.1017/S1744137416000400 ©Cambridge UniversityPress 2016This introduction considers the highly influential contribution of Douglass C. North to economic history and institutional economics, as it developed from the 1960s until his death in 2015. It sketches the evolution of his arguments concerning the roles of institutions, organizations and human agency. North’s conception of the economic actor became progressively more sophisticated, by acknowledging the role of ideology and adopting insights from cognitive science. Eventually he abandoned the proposition that institutions are generally efficient, to propose instead that sub-optimal institutional forms could persist. A few noted criticisms of North’s work are also considered here, ranging from those which are arguably off the mark, to others that retain some force. The contributions to this memorial issue are outlined at the end of this introduction.Peer reviewe

    Connection and coherence between and among European instruments in the private international law of obligations

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    This article considers points of connection and coherence between and among the Rome I Regulation, the Rome II Regulation, and Regulation 1215, and relevant predecessor instruments. The degree of consistency in aim, design and detail of conflict of laws rules is examined, vertically (between/among consecutive instruments) and horizontally (across cognate instruments). Symbiosis between instruments is explored, as is the interrelationship between choice of court and choice of law. Disadvantaged parties, and the cohesiveness of their treatment under the Regulations, receive particular attention
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