4,385 research outputs found

    Promotion and evacuation on standard Young tableaux of rectangle and staircase shape

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    (Dual-)promotion and (dual-)evacuation are bijections on SYT(\lambda) for any partition \lambda. Let c^r denote the rectangular partition (c,...,c) of height r, and let sc_k (k > 2) denote the staircase partition (k,k-1,...,1). B. Rhoades showed representation-theoretically that promotion on SYT(c^r) exhibits the cyclic sieving phenomenon (CSP). In this paper, we demonstrate a promotion- and evacuation-preserving embedding of SYT(sc_k) into SYT(k^{k+1}). This arose from an attempt to demonstrate the CSP of promotion action on SYT(sc_k).Comment: 14 pages, typos correcte

    Recognizing Uncertainty in Speech

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    We address the problem of inferring a speaker's level of certainty based on prosodic information in the speech signal, which has application in speech-based dialogue systems. We show that using phrase-level prosodic features centered around the phrases causing uncertainty, in addition to utterance-level prosodic features, improves our model's level of certainty classification. In addition, our models can be used to predict which phrase a person is uncertain about. These results rely on a novel method for eliciting utterances of varying levels of certainty that allows us to compare the utility of contextually-based feature sets. We elicit level of certainty ratings from both the speakers themselves and a panel of listeners, finding that there is often a mismatch between speakers' internal states and their perceived states, and highlighting the importance of this distinction.Comment: 11 page

    The magnetic environment of the Orion-Eridanus superbubble as revealed by Planck

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    Using the 353-GHz polarization observations by the Planck satellite we characterize the magnetic field in the Orion-Eridanus superbubble, a nearby expanding structure that spans more than 1600 square degrees in the sky. We identify a region of both low dispersion of polarization orientations and high polarization fraction associated with the outer wall of the superbubble identified in the most recent models of the large-scale shape of the region. We use the Davis-Chandrasekhar-Fermi method to derive plane-of-the-sky magnetic field strengths of tens of microGauss toward the southern edge of the bubble. The comparison of these values with existing Zeeman splitting observations of HI in emission suggests that the large-scale magnetic field in the region was primarily shaped by the expanding superbubble.Comment: 7 pages, 8 figures. Accepted for publication as a Letter in A&A, section 1. Letters to the Editor (08/12/2017

    Organic Apple Production in Washington State: An Input-Output Analysis

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    This paper provides an Input-Output (I/O) based economic impact analysis for organic apple production in Washington State. The intent is to compare the economic “ripple” effect of organic production with conventional production. The analysis is presented in two scenarios: first we compare the economic impact of organic versus conventional apple production for a l demand increase of one million US$ as measured in sales. The second analysis looks at the economic impact of organic and conventional apple production in terms of given unit of land (405 hectares of production). Both state-wide output (sales) and employment (jobs) impacts are estimated under each scenario. Results are presented in terms of direct, indirect, and induced economic impact. Organic apple production was more labor intensive than conventional production. While, the organic apple sector used less intermediate inputs per unit of output than conventional production it also produced higher returns to labor and capital. As a result, the indirect economic effect was lower for the organic sector than the conventional sector, but the induced economic effect was higher for organic. Given the organic price premium, the economic impact (direct, indirect and induced) was larger for organic apple production than conventional apple production.conventional and organic apple production, multiplier effects, output, and employment effects, IMPLAN

    Kompaneets Model Fitting of the Orion-Eridanus Superbubble

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    Winds and supernovae from OB associations create large cavities in the interstellar medium referred to as superbubbles. The Orion molecular clouds are the nearest high mass star-forming region and have created a highly elongated, 20 degree x 45 degree, superbubble. We fit Kompaneets models to the Orion-Eridanus superbubble and find that a model where the Eridanus side of the superbubble is oriented away from the Sun provides a marginal fit. Because this model requires an unusually small scaleheight of 40 pc and has the superbubble inclined 35 degrees from the normal to the Galactic plane, we propose that this model should be treated as a general framework for modelling the Orion-Eridanus superbubble, with a secondary physical mechanism not included in the Kompaneets model required to fully account for the orientation and elongation of the superbubble.Comment: 15 pages, 5 figures, 2 tables, accepted by MNRAS, minor grammatical change

    On a whale shark Rhincodon typus (Smith) caught off Manapad, Gulf of Mannar

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    A stray whale shark Rhincodon typus was caught accidentally from the Gulf of Mannar and was landed at Periyathalai on 27th November 1997. The sheirk measuring 5.93 m and weighing 2 tonnes (approximately) got entangled in the Paruvalai net of mesh size 12-15 cm operated at a depth of 30 m in the Manapad fishing ground during the very early hours (0015 hrs) of the day by a kattamaran. The shark was towed ashore with the help of the neighbouring crew members of a fibre-glass boat and three other Kattamarans and was landed at Periyathalai at 1130 hrs. Locally this shark is called as 'Uravi' or 'Ammuni uluvai'. For the whole day it was lying on the shore because of lack of demand

    Blockchain will usher in the era of decentralised computing

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    It’s time for us, not corporations, to control our own digital information and assets, argues Bruce Po

    Finding Eyewitness Tweets During Crises

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    Disaster response agencies have started to incorporate social media as a source of fast-breaking information to understand the needs of people affected by the many crises that occur around the world. These agencies look for tweets from within the region affected by the crisis to get the latest updates of the status of the affected region. However only 1% of all tweets are geotagged with explicit location information. First responders lose valuable information because they cannot assess the origin of many of the tweets they collect. In this work we seek to identify non-geotagged tweets that originate from within the crisis region. Towards this, we address three questions: (1) is there a difference between the language of tweets originating within a crisis region and tweets originating outside the region, (2) what are the linguistic patterns that can be used to differentiate within-region and outside-region tweets, and (3) for non-geotagged tweets, can we automatically identify those originating within the crisis region in real-time

    Teaching TAs To Teach: Strategies for TA Training

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    "The only thing that scales with undergrads is undergrads". As Computer Science course enrollments have grown, there has been a necessary increase in the number of undergraduate and graduate teaching assistants (TAs, and UTAs). TA duties often extend far beyond grading, including designing and leading lab or recitation sections, holding office hours and creating assignments. Though advanced students, TAs need proper pedagogical training to be the most effective in their roles. Training strategies have widely varied from no training at all, to semester-long prep courses. We will explore the challenges of TA training across both large and small departments. While much of the effort has focused on teams of undergraduates, most presenters have used the same tools and strategies with their graduate students. Training for TAs should not just include the mechanics of managing a classroom, but culturally relevant pedagogy. The panel will focus on the challenges of providing "just in time", and how we manage both intra-course training and department or campus led courses
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