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  • Tim Nieberg, H Bodlaender, H J Broersma, P Brucker, P J M Havinga, J L Hurink +18 others
  • 2004
Dit proefschrift is goedgekeurd door Acknowledgements Working towards a PhD is a long road with many bends and turns. It is impossible to do on one's own, and I had help and advice from a lot of people both from the academic and the 'real' world. In the end, it is this help that kept me going on this road, and made this trip the trip of my life. I am(More)
We present the progress on the benchmarking project for high school timetabling that was introduced at PATAT 2008. In particular, we announce the High School Timetabling Archive XHSTT-2011 with 21 instances from 8 countries and an evaluator capable of checking the syntax of instances and evaluating the solutions.
The first step in constructing timetables in secondary schools in Netherlands consists of constructing the clusterschemes for the higher classes. A clusterscheme contains clusterlines with optional subjects that will be taught in parallel; the problem is to divide these optional subjects in clusterlines, such that the number of hours needed is as low as(More)
In this paper we propose a neighbourhood structure based on sequential/cyclic moves and a Cyclic Transfer algorithm for the high school timetabling problem. This method enables execution of complex moves for improving an existing solution, while dealing with the challenge of exploring the neighbourhood efficiently. An improvement graph is used in which(More)
We study finite-dimensional Lie algebras L of polynomial vector fields in n variables that contain the vector fields ∂ ∂x i and x 1 ∂ ∂x 1 + · · · + x n ∂ ∂x n. We show that the maximal ones always contain a semi-simple subalgebra ¯ g, such that ∂ ∂x i ∈ ¯ g (i = 1,. .. , m) for an m with 1 ≤ m ≤ n. Moreover a maximal algebra has no trivial ¯ g-module in(More)
  • Sophie Van Veldhoven, Gerhard Post, Egbert Van Der Veen, Tim Curtois, Asap
  • 2013
This paper studies a two-phase decomposition approach to solve the personnel scheduling problem. The first phase creates a days off schedule, indicating working days and days off for each employee. The second phase assigns shifts to the working days in the days off schedule. This decomposition is motivated by the fact that personnel scheduling constraints(More)
We study finite-dimensional Lie algebras of polynomial vector fields in n variables that contain the vector fields ∂ ∂x i x 1 ∂ ∂x 1 + · · · + x n ∂ ∂x n. We derive some general results on the structure of such Lie algebras, and provide the complete classification in the cases n = 2 and n = 3. Finally we describe a certain construction in high dimensions.(More)