13 research outputs found
Gelungene Versöhnung - unsichere Zukunft? Zur Raison d'être der deutsch-französischen Beziehungen in der neuen Europäischen Union
"Die Frage nach der Notwendigkeit und Legitimität der deutsch-französischen Sonderbeziehung im Europa der 25 stellt sich nach der Ablehnung der Europäischen Verfassung in Frankreich und den Niederlanden sowie dem vorläufigen Scheitern der EU-Finanzverhandlungen umso dringlicher. Mit der Rolle und Perzeption der deutsch-französischen Zusammenarbeit in der erweiterten Europäischen Union setzte sich im Juni ein internationales Kolloquium mit dem Titel 'Gelungene Versöhnung – unsichere Zukunft?' in Erinnerung an Joseph Rovan auseinander, dessen Tagungsergebnisse das Dossier dokumentiert. Neben Beiträgen zur Bewertung der aktuellen Krise und den Herausforderungen an Deutschland und Frankreich, analysieren (weitere Beiträge) den Blick der anderen Mitgliedstaaten auf das 'couple'." (Autorenreferat
SN 2009bb: a Peculiar Broad-Lined Type Ic Supernova
Ultraviolet, optical, and near-infrared photometry and optical spectroscopy
of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the
flux evolution from -10 to +285 days past B-band maximum. Thanks to the very
early discovery, it is possible to place tight constraints on the SN explosion
epoch. The expansion velocities measured from near maximum spectra are found to
be only slightly smaller than those measured from spectra of the prototype
broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model
to the pseudo-bolometric light curve of SN 2009bb suggests that 4.1+-1.9 Msun
of material was ejected with 0.22 +-0.06 Msun of it being 56Ni. The resulting
kinetic energy is 1.8+-0.7x10^52 erg. This, together with an absolute peak
magnitude of MB=-18.36+-0.44, places SN 2009bb on the energetic and luminous
end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the
early time optical spectra accompanied with strong radio emission, and high
metallicity of its environment makes SN 2009bb a peculiar object. Similar to
the case for GRBs, we find that the bulk explosion parameters of SN 2009bb
cannot account for the copious energy coupled to relativistic ejecta, and
conclude that another energy reservoir (a central engine) is required to power
the radio emission. Nevertheless, the analysis of the SN 2009bb nebular
spectrum suggests that the failed GRB detection is not imputable to a large
angle between the line-of-sight and the GRB beamed radiation. Therefore, if a
GRB was produced during the SN 2009bb explosion, it was below the threshold of
the current generation of gamma-ray instruments.Comment: Accepted for publication in Ap
2018 Research & Innovation Day Program
A one day showcase of applied research, social innovation, scholarship projects and activities.https://first.fanshawec.ca/cri_cripublications/1005/thumbnail.jp
Efficiency of Specialized Genetic Operators in Non-dominated Tournament Genetic Algorithm (NTGA2) Applied to Multi-objective Multi-skill Resource Constrained Project Scheduling Problem
This proceeding paper is an accepted manuscript version accepted for publication, and is subject to Springer Nature’s AM terms of use https://www.springernature.com/gp/open-research/policies/accepted-manuscript-terms. Version of Record: Antkiewicz, M., Myszkowski, P.B., Gmyrek, K., Krzeminski, A., Calvo-Rolle, J.L. (2024). Efficiency of Specialized Genetic Operators in Non-dominated Tournament Genetic Algorithm (NTGA2) Applied to Multi-objective Multi-skill Resource Constrained Project Scheduling Problem. In: Nguyen, NT., et al. Advances in Computational Collective Intelligence. ICCCI 2024. Communications in Computer and Information Science, vol 2166. Springer, Cham. https://doi.org/10.1007/978-3-031-70259-4_816th International Conference on Computational Collective Intelligence, 9-11 September 2024, Leipzig, Germany.[Abstract] The Multi-Objective Multi-Skill Resource Constrained Project Scheduling Problem (MS-RCPSP) is an NP-hard real-world problem that can be solved by metaheuristics like the Non-Dominated Tournament Genetic Algorithm (NTGA2). NTGA2 method is effective as a generic black-box metaheuristic. In the paper, we present experiments to examine how effective NTGA2 is in multi-objective optimization when the black-box rule is omitted, and specialized operators are used: Cheaper Resource Crossover, Less Assignment Crossover, and Resource-Leveling Mutation. Experimental results show that specialized operators have extra computational costs, but finally, the NTGA2 method is the most effective. Results are based on the benchmark iMOPSE library, compared to state-of-the-art methods, and statistically verified
A structural interpretation of the two components governing the kinetic fragility from the example of interpenetrated polymer networks
International audienc