292 research outputs found
POS Tagging and its Applications for Mathematics
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
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 Stellerâs sea cow
Stellerâs 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 Stellerâs descriptions with paleogenomic data from 12 individuals. We identified convergent evolution between Stellerâs 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 Stellerâs sea cowsâ reportedly bark-like skin. We also found that Stellerâs sea cowsâ 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
Die Wucht der derzeitigen Urbanisierungsdynamik und ihre Auswirkungen sind so groĂ, dass sich weltweit StĂ€dte, Stadtgesellschaften, Regierungen und Internationale Organisationen diesem Trend stellen mĂŒssen. Ein âWeiter so wie bisherâ, 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 GroĂe Transformation zur Nachhaltigkeit gelingt. In diesem Buch werden die Erfolgsbedingungen dafĂŒr diskutiert
Humanity on the move: Unlocking the transformative power of cities
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 â i.e. an unstructured, quasi-automatic urbanization â would lead to a non-sustainable âworld cities societyâ. 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
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 , on average
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
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
- âŠ