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Future Meetings

Tutorial on Vehicle Routing

Venue: Project Room 1.06, 50 George Square, Edinburgh EH8 9LH
Speaker: Gilbert Laporte
Date: Monday, 07 September 2015 at 08:30 - 17:30

This is part of the Workshop on vehicle routing on 7th and 8th September. Check the website below for further details.

The operational management of fleets of vehicles in many application areas including the transportation of merchandise and the provision of public services such as waste collection is increasingly challenging with the rise of big data and smart online retailing systems amongst other things. Planners and schedulers of transportation routes for vehicles are often faced with many practical challenges including the combinatorial nature of routing and scheduling problems. Although significant progress has been made on the design of computationally efficient optimal methodologies and algorithms, it remains that the sizes of the problems to be solved in practice tend to favour the use of heuristics approaches and methods.

This World Class Workshop attempts to open the black box of exact and heuristic solution methods for both node and arc routing problems. The objective of this workshop is to enhance our understanding of why certain solution approaches and methods perform very well in some cases, but behave poorly in others. It should also initiate the discussion on future research directions by looking at a number of past and present-day problems. The workshop is primarily designed for researchers (e.g. PhD students, post-docs, and faculty members) in the fields of routing, scheduling and logistics.

This workshop is delivered by a renowned expert Professor Gilbert Laporte from the CIRRELT Research group, to present recent research on routing problems with applications in the area of transportation.

Website and

Contact e-mail address:

Scheduling Philae's Science Campaign Using Constraint Programming

Venue: University of Edinburgh Business School, Lecture Theatre 2 (LG.18)
Speaker: Emmanuel Hebrard
Date: Friday, 25 September 2015 at 14:15 - 16:00

Emmanuel Hebrard

Laboratoire d'Analyse et d'Architecture des Systemes, Toulouse , France

25th September 2015, 2pm,

University of Edinburgh Business School, Lecture Theatre 2 (LG.18),

29 Buccleuch place, EH8 9JS, Edinburgh

Free registration here

Scheduling Philae's Science Campaign Using Constraint Programming

Abstract: On November 12th 2014, the robot-lab Philae was released from the spacecraft Rosetta and landed on the ground of the comet 67P/Churyumov-Gerasimenko. Philae is fitted with ten instruments to conduct the experiments elaborated by as many research teams across Europe. These experiments, should they be imaging, sampling or other types of signal analysis, correspond to sequences of activities constrained by two extremely scarce resources: the energy supplied by a single battery, and the storage memory of its CPU.

The plans executed by Philae are modelled and solved using constraint programming technology. Indeed, Mission Operations Scheduling Tool (MOST), the toolkit used to schedule the lander's activities, was developed by a CNES team based in Toulouse on top of IBM ILOG Scheduler (now IBM CP Optimizer).

I will present the contribution of our group to solving the problem of scheduling Philae's activities. In particular, I shall focus on the design of algorithms for efficiently reasoning about data transfers within Philae and between Philae and Rosetta. These algorithms made it possible to solve in a few seconds long term sequences of activities that otherwise required hours with the previous approach or in some case could not be solved. Moreover, they also give a more accurate prediction of the memory usage, thus giving better guarantees against data loss.

Biography: Emmanuel Hebrard is a CNRS* researcher at the Laboratory for Analysis and Architecture of Systems; University of Toulouse. He has got a Ph.D. from University of New South Wales.

His research interests cover many aspects of combinatorial optimisation in general, and constraint programming in particular, such as the design of solvers and algorithms for constraint propagation, SAT and clause learning, or the complexity and tractable classes of constraint satisfaction problems. Recently, his research was applied in projects with the space industry (CNES and Airbus Defence and Space).

(*) French "National Centre for Scientific Research

Organizer: R. Rossi

Coordinator: R. Rossi