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Knowledge Extraction and Applications utilizing Context Data in Knowledge Graphs

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Knowledge Extraction and Applications utilizing Context Data...

Federated Conference on Computer Science and Information Systems (FedCSIS)

作者： Jens Dörpinghaus Andreas Stefan Schloss Birlinghoven Fraunhofer Institute for Algorithms and Scientific Computing Sankt Augustin Germany

Context is widely considered for NLP and knowledge discovery since it highly influences the exact meaning of natural language. The scientific challenge is not only to extract such context data, but also to store this data for further NLP approaches. Here, we propose a multiple step knowledge graphbased approach to utilize context data for NLP and knowledge expression and extraction. We introduce the graph-theoretic foundation for a general context concept within semantic networks and show a proof-of-concept-based on biomedical literature and text mining. We discuss the impact of this novel approach on text analysis, various forms of text recognition and knowledge extraction and retrieval.

关键词： Text mining Ontologies Databases Semantics Diseases Knowledge discovery

ATK-ForceField: A new generation molecular dynamics software package

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arXiv 2017年

作者： Schneider, Julian Hamaekers, Jan Chill, Samuel T. Smidstrup, Søren Bulin, Johannes Thesen, Ralph Blom, Anders Stokbro, Kurt QuantumWise A/S Fruebjergvej 3 CopenhagenDK-2100 Denmark Fraunhofer Institute for Algorithms and Scientific Computing SCAI Schloss Birlinghoven Sankt Augustin53754 Germany

ATK-ForceField is a software package for atomistic simulations using classical interatomic potentials. It is implemented as a part of the Atomistix ToolKit (ATK), which is a Python programming environment that makes it easy to create and analyze both standard and highly customized simulations. This paper will focus on the atomic interaction potentials, molecular dynamics, and geometry optimization features of the software, however, many more advanced modeling features are available. The implementation details of these algorithms and their computational performance will be shown. We present three illustrative examples of the types of calculations that are possible with ATK-ForceField: modeling thermal transport properties in a silicon germanium crystal, vapor deposition of selenium molecules on a selenium surface, and a simulation of creep in a copper polycrystal. Copyright © 2017, The Authors. All rights reserved.

关键词： Software packages

Improving Distantly Supervised Extraction of Drug-Drug and Protein-Protein Interactions 12

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Improving Distantly Supervised Extraction of Drug-Drug and P...

Conference of The European Chapter of The Association for Computational Linguistics

作者： Tamara Bobic Roman Klinger Philippe Thomas Martin Hofmann-Apitius Fraunhofer Institute for Algorithms and Scientific Computing (SCAI) Schloss Birlinghoven 53754 Sankt Augustin Germany Bonn-Aachen Center for Information Technology Dahlmannstrasse 2 53113 Bonn Germany Fraunhofer Institute for Algorithms and Scientific Computing (SCAI) Schloss Birlinghoven 53754 Sankt Augustin Germany Computer Science Institut Humboldt-Universitaet Unter den Linden 6 10099 Berlin Germany

ISBN: (纸本)9781622764907

Relation extraction is frequently and successfully addressed by machine learning methods. The downside of this approach is the need for annotated training data, typically generated in tedious manual, cost intensive work. Distantly supervised approaches make use of weakly annotated data, like automatically annotated corpora. Recent work in the biomedical domain has applied distant supervision for protein-protein interaction (PPI) with reasonable results making use of the IntAct database. Such data is typically noisy and heuristics to filter the data are commonly applied. We propose a constraint to increase the quality of data used for training based on the assumption that no self-interaction of real-world objects are described in sentences. In addition, we make use of the University of Kansas Proteomics Service (KUPS) database. These two steps show an increase of 7 percentage points (pp) for the PPI corpus AIMed. We demonstrate the broad applicability of our approach by using the same workflow for the analysis of drug-drug interactions, utilizing relationships available from the drug database DrugBank. We achieve 37.31 % in F_1 measure without manually annotated training data on an independent test set.

关键词： Protein-Protein Interaction Training data pulse position indicator Drug Interactions Heuristics Manual handling Database

Compensation of pressure peaks in PWK-type hydraulic pumps

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Key Engineering Materials 2011年 490卷 33-44页

作者： Osiecki, Leszek Patrosz, Piotr Zawistowski, Tomasz Landvogt, Bettina Piechna, Janusz Zyliñski, Bartek Gdansk University of Technology ul. Narutowicza 11/12 80-233 Gdansk Poland Space Research Center Polish Academy of Sciences ul. Bartycka 18A 00-716 Warszawa Poland Fraunhofer Institute for Algorithms and Scientific Computing SCAI Schloss Birlinghoven 53754 Sankt Augustin Germany Warsaw University of Technology Pl. Politechniki 1 00-661 Warszawa Poland Bandak Engineering Postboks 1505 Ålesund Norway

Hydraulic axial pumps equipped with cam-driven commutation unit (PWK pumps) proved their high efficiency up to 55 MPa and ability to work self-sucking, even at high speed. Displacement of PWK pump may easily be changed by moving its control cam. Full discharge from hydrostatic forces makes such control possible by direct action of a low-energy actuator like proportional electromagnet or stepping motor. That eliminates heavy and costly hydraulic servomechanism, necessary in other variable displacement machines. Such a control mechanism was positively evaluated in prototype tests in Department of Hydraulics and Pneumatics of Gdañsk University of Technology. The new commutation unit generates however harmful pressure peaks. The paper presents the compensation method for pressure peaks by use of the elastic compensation chamber. It shows also results of multidisciplinary FEA and CFD analysis necessary to properly design the compensation chamber. © 2012 Trans Tech Publications, Switzerland.

关键词： Stepping motors

RDM-stars as sources of fast radio bursts

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arXiv 2018年

作者： Nikitin, Igor Fraunhofer Institute for Algorithms and Scientific Computing Schloss Birlinghoven Sankt Augustin53757 Germany

In this work we consider a recently formulated model of a black hole coupled with radially directed flows of dark matter (RDM-star). In this model, a cutoff by quantum gravity (QG) creates a core of Planck density, filled with a gas of Planck mass particles, inside the star. Further, in this model, a fast radio burst (FRB) can be generated via the following mechanism. An object of an asteroid mass falls onto an RDM-star. Due to large gravitational forces available in the interior, the RDM-star works as a powerful accelerator, boosting the nucleons composing the object to extremely high energies. Upon collision with the core, the nucleons enter in deeply inelastic reactions with the Planck particles composing the core. This process is followed by stimulated emission of highly energetic photons. On the way outside, these photons are subjected to a strong redshift factor, downscaling their frequencies to the radio diapason, as a result producing an FRB. A straightforward computation gives a characteristic upper FRB frequency of 0.6GHz. With attenuation factors, it is stretched to a range 0.35-8GHz, fitting well with the observable FRB frequencies. We also discuss the reconstruction of other FRB parameters in frames of the model. Copyright © 2018, The Authors. All rights reserved.

关键词： Stars

A Globally Convergent Method for Generalized Resistive Systems and its Application to Stationary Problems in Gas Transport Networks

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A Globally Convergent Method for Generalized Resistive Syste...

International Conference on Simulation and Modeling Methodologies, Technologies and Applications

作者： Tanja Clees Nils Hornung Igor Nikitin Lialia Nikitina Fraunhofer Institute for Algorithms and Scientific Computing Schloss Birlinghoven 53754 Sankt Augustin Germany

ISBN: (纸本)9781509058945

We consider generalized resistive systems, comprising linear Kirchhoff equations and non-linear element equations, depending on the flow through the element and on two adjacent nodal variables. The derivatives of the element equation should possess a special signature. For such systems we prove the global non-degeneracy of the Jacobi matrix and the applicability of globally convergent solution tracing algorithms. We show that the stationary problems in gas transport networks belong to this generalized resistive type. We apply the tracing algorithm to several realistic networks and compare its performance with a generic Newton solver.

关键词： Non-linear Systems Globally Convergent Methods Gas Transport Networks

On dark stars, planck cores and the nature of dark matter

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arXiv 2021年

作者： Nikitin, Igor Fraunhofer Institute for Algorithms and Scientific Computing Schloss Birlinghoven Sankt Augustin53757 Germany

Dark stars are compact massive objects, described by Einstein gravitational field equations with matter. The type we consider possesses no event horizon, instead, there is a deep gravitational well with a very strong redshift factor. Observationally, dark stars can be identified with black holes. Inside dark stars, Planck density of matter is reached, Planck cores are formed, where the equations are modified by quantum gravity. In the paper, several models of dark stars with Planck cores are considered, resulting in the following hypothesis on the composition of dark matter. The galaxies are flooded with low-energetic radiation from the dark stars. The particle type can be photons and gravitons from the Standard Model, can also be a new type of massless particles. The model estimations show that the extremely large redshift factor z ∼ 1049 and the emission wavelength λ0 ∼ 1014m can be reached. The particles are not registered directly in the existing dark matter experiments. They come in a density sufficient to explain the observable rotation curves. The emission has a geometric dependence of density on radius ρ ∼ r−2, producing flat rotation curves. The distribution of sources also describes the deviations from the flat shape. The model provides a good fit of experimental rotation curves. Outbreaks caused by a fall of an external object on a dark star lead to emission wavelength shifted towards smaller values. The model estimations give the outbreak wavelength λ ∼ 1m compatible with fast radio bursts. The paper raises several principal questions. White holes with Planck core appear to be stable. Galactic rotation curves in the considered setup do not depend on the matter type. Inside the galaxy, dark matter can be of hot radial type. At cosmological distances, it can behave like the cold uniform type. © 2021, CC BY.

关键词： Galaxies

RDM-stars and related topics

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arXiv 2019年

作者： Nikitin, Igor Fraunhofer Institute for Algorithms and Scientific Computing Schloss Birlinghoven Sankt Augustin53757 Germany

In this paper, we will continue to study the model of black holes coupled to the radial flows of dark matter (RDM-stars). According to recent studies, this model well describes the experimental Rotation Curves (RCs) of spiral galaxies, also, RDM-stars can produce signals with the characteristics of Fast Radio Bursts (FRBs). In this paper, we will perform a combined analysis of experimental data on RCs and FRBs, which will allow to constrain tighter parameters of the model. We will also show that within the framework of the model, the Tully-Fisher relation with a slope of β = 3 − 4 can be obtained. Further, several particular solutions will be considered: tachyonic oven – a solution in which the incoming flow of tachyons turns into an outgoing flow of massive particles;shell condensate – a naked singularity of negative mass covered by a thin shell of positive mass, so that the Schwarzschild solution of negative mass inside is joined to one of positive mass outside;also, an RDM solution with a cosmological constant will be considered. Further, in the model under consideration, Penrose diagrams will be constructed, which share common features with Schwarzschild solutions of positive and negative mass, whose combination the model is. The mechanism of effective formation of negative masses in the model is discussed, which is activated when the density of the central core exceeds the Planck value, similarly to the previously studied quantum bounce effect. Copyright © 2019, The Authors. All rights reserved.

关键词： Stars

Quantum gravity wormholes and topological teleporter

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arXiv 2019年

作者： Nikitin, Igor Fraunhofer Institute for Algorithms and Scientific Computing Schloss Birlinghoven Sankt Augustin53757 Germany

The question of a possibility of opening a wormhole due to the deformation of the equation of state of the matter caused by quantum gravity effects is considered. As a wormhole environment, the previously considered model of a galaxy with radial flows of dark matter is selected. The calculation shows, that for a wormhole solution in the framework of this model, after the nominal classical density exceeds a critical value in the Planck range, the components of the energy-momentum tensor become negative in a certain order. First, the mass density becomes negative, then the radial pressure, then the tangential pressure. In this case, at some point the flare-out conditions necessary and sufficient to open the wormhole are fulfilled. Calculations are made to open a wormhole in a model with parameters of the Milky Way galaxy. It is shown that the opening of the wormhole is accompanied by a separation of the bubble of space, completely detached from the wormhole and the outer space. In addition to this solution, a topologically dual one is found, looking like an instant swapping of two volumes in space, which can be interpreted as an event of teleportation. Copyright © 2019, The Authors. All rights reserved.

关键词： Galaxies