Some of my research activities are devoted to optimization/implementation challenges.
In those challenges, an implementation of a solution algorithm for a given optimization problem must be submitted. I am the person doing the coding. Comparisons and rankings are done by the competition organizers (note that this typically also involves data sets that are unavailable to the participants during the challenge).
ACP Challenge 2016 (part of the 22nd International Conference on Principles and Practice of Constraint Programming, September 2016, Toulouse, France): 3rd place.
Optimization problem: scheduling of torpedoes in steel production.
A first conference article describing my contribution: [doi:10.1007/978-3-658-17580-1_4]
Kaggle "Santa's Stolen Sleigh" Problem (held from December 2015–January 2016): 56th (out of 1127 teams), with +0.38% deviation from the winning solution.
Optimization problem: capacitated vehicle routing problem on a sphere with a novel objective function, large graph with 100,000 nodes.
Kaggle "Traveling Santa" Problem competition (held from December 2012–January 2013): 19th (out of 355 teams), with +0.7% deviation from the best known solution.
Optimization problem: finding two edge-disjoint minimal paths in a large graph with 150,000 nodes.
Nurse Rostering Competition (finals held in August 2010 in Belfast, Northern Ireland): finals not reached.
Optimization problem: building a roster for nurses in hospitals (=a timetabling problem).
Conference paper: [doi:10.1007/978-3-642-20009-0_35]
International Timetabling Competition ITC 2007 (finals held in August 2008 in Montréal, Canada): Finalist (= one of the top 5 contributions worldwide).
Optimization problem: curriculum based course timetabling.
Journal paper on my approach: [doi:10.1007/s10479-010-0703-4]