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Welcome to the ORCS Lab
Welcome to the Laboratory of Operational Research and Complex Systems. Feel free to explore the website and get to know our projects and the people behind the algorithms.
ORCS Lab - Optimisation, Data Science and Complex Systems
Research in the ORCS Lab focuses mainly on the development and application of optimisation methods to complex systems; on data science and statistical modeling; and on the applications of computational intelligence to large-scale power and energy systems.

Latest News

We're very happy to announce that the paper:

Integrating Matheuristics and Metaheuristics for Timetabling

by George H.G. Fonseca, Haroldo G. Santos, and Eduardo G. Carrano, has been accepted for publication in the prestigious Computers and Operations Research (IF: 1.861). The paper reports on results that are part of George's Ph.D. work under the supervision of Prof. Carrano, and describes strategies that provide the best known results for 15 out of 17 benchmark instances of the High School Timetabling Problem.

You can read the abstract by clicking the "Read More" button below, or check the early access version of the paper here.


Abstract: The High School Timetabling Problem requires the assignment of times and resources to events, while sets of required and desirable constraints must be considered. The most common approach for this problem is to employ metaheuristic methods. This work presents a matheuristic approach that combines a Variable Neighbourhood Search algorithm with mathematical programming-based neighbourhoods for high school timetabling. Computational experiments on well-known benchmark instances demonstrate the success of the proposed hybrid approach, which outperforms the standalone Variable Neighbourhood Search algorithm by far. Additionally, the proposed algorithm was able to improve 15 out of 17 current best known solutions in a very famous benchmark set.