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DTSTART:20221030T030000
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UID:calendar.24976.field_data.0@www.diag.uniroma1.it
DTSTAMP:20260407T194402Z
CREATED:20230123T085438Z
DESCRIPTION:AbstractEfficient solution approaches for quadratic unconstrain
 ed binary optimization (QUBO) problems are of great interest for several r
 easons. Firstly\, the well-known maximum-cut problem admits a natural form
 ulation as a QUBO problem. Secondly\, other optimization problems like the
  graph bisection problem\, the maximum independent set problem\, linearly 
 constrained binary quadratic problems\, and many more can be reformulated 
 as an instance of QUBO. Since linear programming based approaches perform 
 poorly on dense problem instances\, all state-of-the-art approaches involv
 e semidefinite relaxations in this case. In this talk\, we present an exac
 t solver for QUBO problems based on semidefinite programming. It uses the 
 so-called mixing method\, a low-rank coordinate descent method\, as its ma
 in tool to tackle the occurring semidefinite programs. We discuss some new
  ideas implemented in the solver and provide numerical results showing tha
 t it outperforms the other existing semidefinite approaches for medium-siz
 ed instances. Moreover\, it was a paradigm in recent years to tighten semi
 definite relaxations by considering more and more valid inequalities. In c
 ontrast to this\, we demonstrate that weaker relaxations can still be comp
 etitive when used in a branch-and-bound approach.
DTSTART;TZID=Europe/Paris:20230126T103000
DTEND;TZID=Europe/Paris:20230126T103000
LAST-MODIFIED:20230123T092500Z
LOCATION:Aula A4 Diag
SUMMARY:An Exact Solver for QUBO Problems using the Mixing Method - Jan Sch
 widessen
URL;TYPE=URI:http://www.diag.uniroma1.it/node/24976
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