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X-ORIGINAL-URL:https://alop.uni-trier.de
X-WR-CALDESC:Events for ALOP
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BEGIN:VEVENT
DTSTART;VALUE=DATE:20180301
DTEND;VALUE=DATE:20180304
DTSTAMP:20180131T160745Z
CREATED:20180131T160745Z
LAST-MODIFIED:20180131T160745Z
UID:1839-1519862400-1520121599@alop.uni-trier.de
SUMMARY:Retreat in Daun
DESCRIPTION:The Research Training Group plans its second retreat in Daun on the weekend of March 1 through March 3\, 2018. The researchers will present their work during this retreat\, followed by discussions and feedback from their advisors and fellow PhD students. Several team building events will also take place to complete the program.
URL:https://alop.uni-trier.de/event/retreat-in-daun/
CATEGORIES:Retreat
ORGANIZER;CN="Research Training Group ALOP at Trier University":MAILTO:OptimizationDays@uni-trier.de
END:VEVENT
BEGIN:VEVENT
DTSTART;VALUE=DATE:20180301
DTEND;VALUE=DATE:20180304
DTSTAMP:20180305T085427Z
CREATED:20180305T085427Z
LAST-MODIFIED:20180305T085427Z
UID:1873-1519862400-1520121599@alop.uni-trier.de
SUMMARY:ALOP held its second retreat in Daun
DESCRIPTION:In order to further the individual research projects and improve the team building process\, the Research Training Group Algorithmic Optimization (ALOP) spent three days at the Sporthotel Grafenwald in Daun. In addition to individual presentations by the PhD Students\, the event included in depth discussions on scientific and organizational aspects. \nFurthermore\, the RTG enjoyed a hike and an informative evening program which served to cultivate the pleasant team environment.
URL:https://alop.uni-trier.de/event/alop-held-its-second-retreat-in-daun/
CATEGORIES:Retreat
ATTACH;FMTTYPE=image/jpeg:https://alop.uni-trier.de/wp-content/uploads/2018/03/Retreat-2018.jpg
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BEGIN:VEVENT
DTSTART;VALUE=DATE:20180305
DTEND;VALUE=DATE:20180307
DTSTAMP:20180228T133839Z
CREATED:20180201T075639Z
LAST-MODIFIED:20180228T133839Z
UID:1843-1520208000-1520380799@alop.uni-trier.de
SUMMARY:Prof. Juan Vera and Olga Kuryatnikova of Tilburg University to visit in March
DESCRIPTION:Prof. Juan Vera and Olga Kuryatnikova of Tilburg University are scheduled to visit the Research Training Group ALOP in March for research collaboration. \n  \nDuring their visit\, they will speak on the following topics: \n  \nCopositive certificates of non-negativity (Prof. Juan Vera) \nAbstract: \nSum-of-squares (sos) certificates of non-negativity\, such as Putinar’s Positivstellensatz\, have been used to obtain powerful numerical techniques to solve polynomial optimization (PO) problems. Using such certificates\, hierarchies of semidefinite relaxations are obtained for PO. Usually the use of sos-certificates requires compactness or stronger assumptions on the feasible set\, limiting the range of applications. \nWe show that under suitable conditions on the polynomial h(x) and the set S\, the non-negativity of a polynomial over the set  {x in S: h(x) = 0} can be certified in terms of the non-negative polynomials on S even if the set S is unbounded. Moreover\, a characterization of the pairs (S\, h) for which  such type of non-negativity certificate exists is provided in terms of an appropriate condition on S and h. Moreover\, the non-negativity certificate presented here readily allows the use of copositive polynomials (as opposed to the more common use of sos). In particular it encompasses the results of Burer and Pena-Vera-Zuluaga for representation of polynomial optimization problems as copositive ones. \n  \nApproximating the cone of copositive kernels with application to the kissing number problem. (Olga Kuryatnikova) \nAbstract: \nRecent research has shown how to generalize copositive formulations of the stable set problem in finite graphs to infinite graphs. This allows to express the kissing number problem\, i.e.\, finding the maximum number of non-overlapping unit spheres that can simultaneously touch another unit sphere\, as an optimization problem over copositive kernels. We generalize two existing approximations to the cone of copositive matrices to obtain approximations to the cone of copositive kernels. \nUsing the latter approximations\, we construct a hierarchy of upper bounds on the kissing number. As a side result\, we characterize positive definite functions invariant under automorphisms of the sphere fixing a given set of points. The presentation will be self-contained. \n  \nThe presentations will take place on Monday March 5 at 10:30 c.t. in E 51.
URL:https://alop.uni-trier.de/event/prof-juan-vera-and-olga-kuryatnikova-of-tilburg-university-to-visit-in-march/
LOCATION:Trier University\, E Building\, Universitätsring 15\, Trier\, Germany
CATEGORIES:Colloquium,Scientific Research Collaboration
ORGANIZER;CN="Research Training Group ALOP at Trier University":MAILTO:OptimizationDays@uni-trier.de
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