292 research outputs found

    POS Tagging and its Applications for Mathematics

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    Content analysis of scientific publications is a nontrivial task, but a useful and important one for scientific information services. In the Gutenberg era it was a domain of human experts; in the digital age many machine-based methods, e.g., graph analysis tools and machine-learning techniques, have been developed for it. Natural Language Processing (NLP) is a powerful machine-learning approach to semiautomatic speech and language processing, which is also applicable to mathematics. The well established methods of NLP have to be adjusted for the special needs of mathematics, in particular for handling mathematical formulae. We demonstrate a mathematics-aware part of speech tagger and give a short overview about our adaptation of NLP methods for mathematical publications. We show the use of the tools developed for key phrase extraction and classification in the database zbMATH

    Machine Learning for Mathematical Software

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    While there has been some discussion on how Symbolic Computation could be used for AI there is little literature on applications in the other direction. However, recent results for quantifier elimination suggest that, given enough example problems, there is scope for machine learning tools like Support Vector Machines to improve the performance of Computer Algebra Systems. We survey the authors own work and similar applications for other mathematical software. It may seem that the inherently probabilistic nature of machine learning tools would invalidate the exact results prized by mathematical software. However, algorithms and implementations often come with a range of choices which have no effect on the mathematical correctness of the end result but a great effect on the resources required to find it, and thus here, machine learning can have a significant impact.Comment: To appear in Proc. ICMS 201

    Genomic basis for skin phenotype and cold adaptation in the extinct Steller’s sea cow

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    Steller’s sea cow, an extinct sirenian and one of the largest Quaternary mammals, was described by Georg Steller in 1741 and eradicated by humans within 27 years. Here, we complement Steller’s descriptions with paleogenomic data from 12 individuals. We identified convergent evolution between Steller’s sea cow and cetaceans but not extant sirenians, suggesting a role of several genes in adaptation to cold aquatic (or marine) environments. Among these are inactivations of lipoxygenase genes, which in humans and mouse models cause ichthyosis, a skin disease characterized by a thick, hyperkeratotic epidermis that recapitulates Steller’s sea cows’ reportedly bark-like skin. We also found that Steller’s sea cows’ abundance was continuously declining for tens of thousands of years before their description, implying that environmental changes also contributed to their extinction

    Der Umzug der Menschheit: Die transformative Kraft der StÀdte

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    Die Wucht der derzeitigen Urbanisierungsdynamik und ihre Auswirkungen sind so groß, dass sich weltweit StĂ€dte, Stadtgesellschaften, Regierungen und Internationale Organisationen diesem Trend stellen mĂŒssen. Ein „Weiter so wie bisher“, wĂŒrde ohne gestaltende Urbanisierungspolitik zu einer nicht-nachhaltigen Welt-StĂ€dte-Gesellschaft fĂŒhren. Nur wenn StĂ€dte und Stadtgesellschaften ausreichend handlungsfĂ€hig werden, können sie ihre Kraft fĂŒr eine nachhaltige Entwicklung entfalten: In den StĂ€dten wird sich entscheiden, ob die Große Transformation zur Nachhaltigkeit gelingt. In diesem Buch werden die Erfolgsbedingungen dafĂŒr diskutiert

    Humanity on the move: Unlocking the transformative power of cities

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    The momentum of urbanization and its impacts are so massive that we must face up to this trend. In view of the existing cognitive, technical, economic and institutional path dependencies, a policy of business as usual – i.e. an unstructured, quasi-automatic urbanization – would lead to a non-sustainable ‘world cities society’. Only if cities and urban societies are sufficiently empowered can they make use of the opportunities for sustainability and successfully follow the urban transformation pathways. The success or failure of the Great Transformation will be decided in the cities. The WBGU discusses the relevant conditions for the success of this transformation in this report

    All-sky search for time-integrated neutrino emission from astrophysical sources with 7 years of IceCube data

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    Since the recent detection of an astrophysical flux of high energy neutrinos, the question of its origin has not yet fully been answered. Much of what is known about this flux comes from a small event sample of high neutrino purity, good energy resolution, but large angular uncertainties. In searches for point-like sources, on the other hand, the best performance is given by using large statistics and good angular reconstructions. Track-like muon events produced in neutrino interactions satisfy these requirements. We present here the results of searches for point-like sources with neutrinos using data acquired by the IceCube detector over seven years from 2008--2015. The discovery potential of the analysis in the northern sky is now significantly below EÎœ2dϕ/dEÎœ=10−12 TeV cm−2 s−1E_\nu^2d\phi/dE_\nu=10^{-12}\:\mathrm{TeV\,cm^{-2}\,s^{-1}}, on average 38%38\% lower than the sensitivity of the previously published analysis of four years exposure. No significant clustering of neutrinos above background expectation was observed, and implications for prominent neutrino source candidates are discussed.Comment: 19 pages, 17 figures, 3 tables; ; submitted to The Astrophysical Journa

    Neutrinos and Cosmic Rays Observed by IceCube

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    The core mission of the IceCube Neutrino observatory is to study the origin and propagation of cosmic rays. IceCube, with its surface component IceTop, observes multiple signatures to accomplish this mission. Most important are the astrophysical neutrinos that are produced in interactions of cosmic rays, close to their sources and in interstellar space. IceCube is the first instrument that measures the properties of this astrophysical neutrino flux, and constrains its origin. In addition, the spectrum, composition and anisotropy of the local cosmic-ray flux are obtained from measurements of atmospheric muons and showers. Here we provide an overview of recent findings from the analysis of IceCube data, and their implications on our understanding of cosmic rays.Comment: Review article, to appear in Advances in Space Research, special issue "Origins of Cosmic Rays
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