Instance1

Brazil Instance 1

Brazil Instance 1 was provided in XHSTT by Haroldo Santos. It was initially created by M.J.F. Souza. It is an artificial problem created to test algorithm parameters. Although it is very small, it remains relatively hard to solve by heuristics in a short amount of time.


This instance was corrected on April 1, 2015, by making the PreferTimesConstraint a hard constraint. Lowerbounds remain correct after change.

Due to this the solution for this instance in the solution group LectioIntegerProgramming submitted on 13 September 2013 by Simon Kristiansen et al. with cost 38 turned infeasible, and has been removed from the list of best solutions. Matias Sørensen submitted a newly generated solution on April 4, 2015.

A summary of the data can be found in the following table:

Assets

Times

Teachers

Rooms

Students

Classes

# events

Total duration

value

25

8

-

-

3

21

75

The following constraints are present:
  • Scheduling constraints: AssignTimeConstraint and SplitEventsConstraint.
  • Event constraints: DistributeSplitEventsConstraint, PreferTimesConstraint, and SpreadEventsConstraint.
  • Resource constraints: AvoidClashesConstraint, LimitIdleTimesConstraint, and ClusterBusyTimesConstraint.

The following (feasible) solutions are submitted for this instance:

SolutionGroup

Objective value

Lowerbound

Submitted by

Received

Haroldo_Dec_2011

42

-

Haroldo Santos

December 14, 2011

LectioIntegerProgramming

-

38

Simon Kristiansen et al.

September 13, 2013

LectioIntegerProgramming

41

41

Matias Sørensen

April 4, 2015

XML file

BrazilInstance1.xml (instance and solutions)


previous versions:

BrazilInstance1.xml (XHSTT2013)
[Update to 2014: cost function simplified.]

BrazilInstance1.xml (XHSTT2012)
[Update to 2013: Added unavailabilities of the teachers.]

BrazilInstance1.xml (XHSTT2011)
[Update to 2012: Spreading of subevents improved; soft constraints added.]

BrazilInstance1.xml (XHSTT2010)
[Update to 2011: Throughout renamed "SchoolClass" to "Class".]