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München, Germany

Chen J.,University of Electronic Science and Technology of China | Schinner A.,T Systems GEI GmbH | Matuttis H.-G.,University of Electro - Communications
Physics Procedia | Year: 2010

We show how Differential Algebraic Systems (Ordinary Differential Equations with algebraic constraints) in mechanics are affected by stability issues and we implement Lubich's projection method to reduce the error to practically zero. Then, we explain how the "numerically exact" implementation for static friction by Differential Algebraic Systems can be stabilized. We conclude by comparing the corresponding steps in the "Contact mechanics" introduced by Moreau. © 2010 Published by Elsevier Ltd.

Chen J.,University of Electro - Communications | Schinner A.,T Systems GEI GmbH | Matuttis H.-G.,University of Electro - Communications
Theoretical and Applied Mechanics Japan | Year: 2011

The discrete element method allows the simulation of complex behavior of granular materials without constitutive laws. While in two dimensions shape-effects are well established, in three dimensions there is no universally applicable simulation algorithm for non-spherical particles. We will first present a force model for convex polyhedral particles, using the overlap of non-deformed polyhedra as a measure of the elastic force and explain the overlap computation algorithm. With this elastic force model, we then show that the continuum-mechanical sound velocity can be recovered for a space-filling packing of cubic blocks. Further, we show simulation results for heaps for which we obtain realistic high angles of repose, which corroborates the reliability of our simulation method and which further more shows that with our method, a larger phenomenology is accessible than with round particles. © 2011 by National Committee for IUTAM.

Wilbois T.,T Systems GEI GmbH | Ren Y.,T Systems GEI GmbH | Neff U.,LUBW Regional Office for Environment Measurements and Nature Conservation Baden Wuerttemberg | Scheuermann W.,University of Stuttgart | And 2 more authors.
Radioprotection | Year: 2013

The nuclear reactor remote monitoring system of the federal state of Baden-Wuerttemberg (KFUe BW) is realized according to the renewed "recommendations for remote monitoring of nuclear power plants" (BMU, 2005a). The spectrum of the system covers both, pursuit of operational procedures, and incidents or accidents. The KFUe BW provides a measurement network and information system for operational parameters at the plant sites as well as radiological and meteorological measurements in their vicinity. For the Ministry, it preferentially serves as an instrument of nuclear supervision. This paper gives a brief survey of the system architecture and concentrates on the role of the KFUe with respect to the determination and evaluation of the radiological situation in the range of off-site emergency management. © 2013 EDP Sciences.

Von Arx C.,Swiss Federal Nuclear Safety Inspectorate ENSI | Brucher L.,AREVA | De Donno V.,T Systems GEI GmbH | Gerich B.,Federal office for Radiation Protection | And 10 more authors.
HARMO 2014 - 16th International Conference on Harmonisation within Atmospheric Dispersion Modelling for Regulatory Purposes, Proceedings | Year: 2014

Within nuclear emergency planning and preparedness, atmospheric dispersion models are used as central tools for decision support in order to recommend disaster control measures. These measures are closely linked to reference levels for specific dose quantities which are obtained as model results. This paper gives an overview of a comParison of dispersion models being in operation in Germany, which have been optimized for the specific responsibilities of the authorities involved. Results for air concentrations, soil contaminations and the most important dose parameters are collated for different meteorological conditions. © Crown Copyright 2014 Dstl.

Wilbois T.,T Systems GEI GmbH | Haas H.,KRAFTWERK | Poppe W.,KRAFTWERK | Chaves F.,Fraunhofer Institute for Optronics, System Technologies and Image Exploitation | Ren Y.,T Systems GEI GmbH
Kerntechnik | Year: 2011

During the last years the introduction of an electronic situation report system in nuclear power plants has been intensively discussed in the working group emergency staff coordinators of the VGB ('Verband der Grofikraftwerksbetreiber'). In parallel, many federal state authorities as well as the German Ministry of the Environment already successfully started to operate such a system. Based on a solution developed for the ministry for environment Baden-Württemberg, the specific requirements are adapted and extended for the operation in a nuclear power plant. The most important features are easy handling, open interfaces to the systems of the authorities, and flexibility for functional extensions. The advantages recognized after the first test stages led the nuclear power plants Biblis and Neckarwestheim to the decision to introduce such a system at the plant site. First progress and experience gained are reported from the perspective of the crisis management group of the power plant. © Carl Hanser Verlag, München.

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