5,229 research outputs found

    Short-Run Economic Impacts of Hurricane Katrina (and Rita)

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    Sturm; Erdölförderung; Offshore-Industrie; Makroökonomischer Einfluss; USA

    Line Strengths of Rovibrational and Rotational Transitions in the X2Π^2\Pi Ground State of OH

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    A new line list including positions and absolute intensities (in the form of Einstein AA values and oscillator strengths) has been produced for the OH ground X\DP\ state rovibrational (Meinel system) and pure rotational transitions. All possible transitions are included with v\primed and v\Dprimed up to 13, and JJ up to between 9.5 and 59.5, depending on the band. An updated fit to determine molecular constants has been performed, which includes some new rotational data and a simultaneous fitting of all molecular constants. The absolute line intensities are based on a new dipole moment function, which is a combination of two high level ab initio calculations. The calculations show good agreement with an experimental v=1 lifetime, experimental μv\mu_\mathrm{v} values, and Δ\Deltav=2 line intensity ratios from an observed spectrum. To achieve this good agreement, an alteration in the method of converting matrix elements from Hund's case (b) to (a) was made. Partitions sums have been calculated using the new energy levels, for the temperature range 5-6000 K, which extends the previously available (in HITRAN) 70-3000 K range. The resulting absolute intensities have been used to calculate O abundances in the Sun, Arcturus, and two red giants in the Galactic open and globular clusters M67 and M71. Literature data based mainly on [O I] lines are available for the Sun and Arcturus, and excellent agreement is found.Comment: 17 pages, 8 figues. 7 supplementary files: dipole moment functions (OH-X-DMFs.txt), equilibrium constants (OH-X-Equilibrium_Constants.txt), partition function (OH-X-Q_5-6000K.dat), PGOPHER file with molecular constants and transition matric elements (OH-XX.pgo), vibrational Einstein A and f values (OH-XX-Avv_fvv.txt), line list (OH-XX-Line_list.txt), and OH-Transformation_Equation_Extra.doc

    K-Space at TRECVid 2007

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    In this paper we describe K-Space participation in TRECVid 2007. K-Space participated in two tasks, high-level feature extraction and interactive search. We present our approaches for each of these activities and provide a brief analysis of our results. Our high-level feature submission utilized multi-modal low-level features which included visual, audio and temporal elements. Specific concept detectors (such as Face detectors) developed by K-Space partners were also used. We experimented with different machine learning approaches including logistic regression and support vector machines (SVM). Finally we also experimented with both early and late fusion for feature combination. This year we also participated in interactive search, submitting 6 runs. We developed two interfaces which both utilized the same retrieval functionality. Our objective was to measure the effect of context, which was supported to different degrees in each interface, on user performance. The first of the two systems was a ‘shot’ based interface, where the results from a query were presented as a ranked list of shots. The second interface was ‘broadcast’ based, where results were presented as a ranked list of broadcasts. Both systems made use of the outputs of our high-level feature submission as well as low-level visual features

    Formal Component-Based Semantics

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    One of the proposed solutions for improving the scalability of semantics of programming languages is Component-Based Semantics, introduced by Peter D. Mosses. It is expected that this framework can also be used effectively for modular meta theoretic reasoning. This paper presents a formalization of Component-Based Semantics in the theorem prover Coq. It is based on Modular SOS, a variant of SOS, and makes essential use of dependent types, while profiting from type classes. This formalization constitutes a contribution towards modular meta theoretic formalizations in theorem provers. As a small example, a modular proof of determinism of a mini-language is developed.Comment: In Proceedings SOS 2011, arXiv:1108.279

    K-Space at TRECVid 2008

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    In this paper we describe K-Space’s participation in TRECVid 2008 in the interactive search task. For 2008 the K-Space group performed one of the largest interactive video information retrieval experiments conducted in a laboratory setting. We had three institutions participating in a multi-site multi-system experiment. In total 36 users participated, 12 each from Dublin City University (DCU, Ireland), University of Glasgow (GU, Scotland) and Centrum Wiskunde & Informatica (CWI, the Netherlands). Three user interfaces were developed, two from DCU which were also used in 2007 as well as an interface from GU. All interfaces leveraged the same search service. Using a latin squares arrangement, each user conducted 12 topics, leading in total to 6 runs per site, 18 in total. We officially submitted for evaluation 3 of these runs to NIST with an additional expert run using a 4th system. Our submitted runs performed around the median. In this paper we will present an overview of the search system utilized, the experimental setup and a preliminary analysis of our results

    James Bowdoin: Patriot and Man of The Enlightenment

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    An exhibition held at the Bowdoin College Museum of Art, Brunswick, Maine, May 28 through September 12, 1976.https://digitalcommons.bowdoin.edu/art-museum-exhibition-catalogs/1019/thumbnail.jp

    Hidden in plain sight: a massive, dusty starburst in a galaxy protocluster at z=5.7 in the COSMOS field

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    We report the serendipitous discovery of a dusty, starbursting galaxy at z=5.667z=5.667 (hereafter called CRLE) in close physical association with the "normal" main-sequence galaxy HZ10 at z=5.654z=5.654. CRLE was identified by detection of [CII], [NII] and CO(2-1) line emission, making it the highest redshift, most luminous starburst in the COSMOS field. This massive, dusty galaxy appears to be forming stars at a rate of at least 1500M\,M_\odot yr1^{-1} in a compact region only 3\sim3 kpc in diameter. The dynamical and dust emission properties of CRLE suggest an ongoing merger driving the starburst, in a potentially intermediate stage relative to other known dusty galaxies at the same epoch. The ratio of [CII] to [NII] may suggest that an important (15%\sim15\%) contribution to the [CII] emission comes from a diffuse ionized gas component, which could be more extended than the dense, starbursting gas. CRLE appears to be located in a significant galaxy overdensity at the same redshift, potentially associated with a large-scale cosmic structure recently identified in a Lyman Alpha Emitter survey. This overdensity suggests that CRLE and HZ10 reside in a protocluster environment, offering the tantalizing opportunity to study the effect of a massive starburst on protocluster star formation. Our findings support the interpretation that a significant fraction of the earliest galaxy formation may occur from the inside out, within the central regions of the most massive halos, while rapidly evolving into the massive galaxy clusters observed in the local Universe.Comment: 16 pages, 9 figures, 4 tables, final version to appear on ApJ (accepted May 19, 2018

    The 2011 Eruption of the Recurrent Nova T Pyxidis; the Discovery, the Pre-eruption Rise, the Pre-eruption Orbital Period, and the Reason for the Long Delay

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    We report the discovery by M. Linnolt on JD 2455665.7931 (UT 2011 April 14.29) of the sixth eruption of the recurrent nova T Pyxidis. This discovery was made just as the initial fast rise was starting, so with fast notification and response by observers worldwide, the entire initial rise was covered (the first for any nova), and with high time resolution in three filters. The speed of the rise peaked at 9 mag/day, while the light curve is well fit over only the first two days by a model with a uniformly expanding sphere. We also report the discovery by R. Stubbings of a pre-eruption rise starting 18 days before the eruption, peaking 1.1 mag brighter than its long-time average, and then fading back towards quiescence 4 days before the eruption. This unique and mysterious behavior is only the fourth known anticipatory rise closely spaced before a nova eruption. We present 19 timings of photometric minima from 1986 to February 2011, where the orbital period is fast increasing with P/dot{P}=313,000 yrs. From 2008-2011, T Pyx had a small change in this rate of increase, so that the orbital period at the time of eruption was 0.07622950+-0.00000008 days. This strong and steady increase of the orbital period can only come from mass transfer, for which we calculate a rate of 1.7-3.5x10^-7 Mo/yr. We report 6116 magnitudes between 1890 and 2011, for an average B=15.59+-0.01 from 1967-2011, which allows for an eruption in 2011 if the blue flux is nearly proportional to the accretion rate. The ultraviolet-optical-infrared spectral energy distribution is well fit by a power law with flux proportional to nu^1.0, although the narrow ultraviolet region has a tilt with a fit of \nu^{1/3}. We prove that most of the T Pyx light is not coming from a disk, or any superposition of blackbodies, but rather is coming from some nonthermal source.Comment: ApJ submitted, 62 pages, 8 figures; much added data, updated analysi

    Antecedents of strategic flexibility:management cognition, firm resources and strategic options

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    Purpose: Current conceptualisations of strategic flexibility and its antecedents are theory-driven, which has resulted in a lack of consensus. To summarise this domain the paper aims to develop and present an a priori conceptual model of the antecedents and outcomes of strategic flexibility. Discussion and insights into the conceptual model, and the relationships specified, are made through a novel qualitative empirical approach. The implications for further research and a framework for further theoretical development are presented. Design/methodology/approach: An exploratory qualitative research design is used applying multiple data collection techniques in a branch network of a large regional retailer in the UK. The development of strategic options and the complex relationship to strategic flexibility is investigated. Findings: The number and type of strategic options developed by managers impact on the degree of strategic flexibility and also on the ability of the firm to achieve competitive differentiation. Additionally, the type of strategic option implemented by managers is dependent on the competitive situation faced at a local level. Evidence of managers' limited perception of competition was identified based on their spatial embeddedness. Research limitations/implications: A single, in-depth case study was used. The data gathered is rich and appropriate for the exploratory approach adopted here. However, generalisability of the findings is limited. Practical implications: Strategic flexibility is rooted in the ability of front-line mangers to develop and implement strategic options; this in turn facilitates competitive differentiation. Originality/value: The research presented is unique in this domain on two accounts. First, theory is developed by presenting an a priori conceptual model, and testing through in-depth qualitative data gathering. Second, insights into strategic flexibility are presented through an examination of managerial cognition, resources and strategic option generation using cognitive mapping and laddering technique. © Emerald Group Publishing Limited
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