193 research outputs found

    Post enrolment based course timetabling: a description of the problem model used for track two of the second International Timetabling Competition

    Get PDF
    In this paper we give a detailed description of the problem model used in track-two of the second International Timetabling Competition, 2007-2008 www.cs.qub.ac.uk/itc2007/). This model is an extension of that used in the first timetabling competition, and we discuss the rationales behind these extensions. We also describe in detail the criteria that are used for judging solution quality and discuss other issues that are related to this. Finally we go over some of the strengths and limitations of the model. This paper can be regarded as the official documentation for track-two of the timetabling competition

    Analysing Similarity in Exam Timetabling

    Get PDF
    In this paper we carry out an investigation of some of the major features of exam timetabling problems with a view to developing a similarity measure. This similarity measure will be used within a case-based reasoning (CBR) system to match a new problem with one from a case-based of previously solved problems. The case base will also store the heuristic for meta-heuristic techniques applied most successfully to each problem stored. The technique(s) stored with the matched case will be retrieved and applied to the new case. The CBR assumption in our system is that similar problems can be solved equally well by the same technique

    University space planning and space-type profiles

    Get PDF
    Universities planning the provision of space for their teaching requirements need to do so in a fashion that reduces capital and maintenance costs whilst still providing a high-quality level of service. Space plans should aim to provide sufficient capacity without incurring excessive costs due to over-capacity. A simple measure used to estimate over-provision is utilisation. Essentially, the utilisation is the fraction of seats that are used in practice, or the ratio of demand to supply. However, studies usually find that utilisation is low, often only 20–40%, and this is suggestive of significant over-capacity. Our previous work has provided methods to improve such space planning. They identify a critical level of utilisation as the highest level that can be achieved whilst still reliably satisfying the demand for places to allocate teaching events. In this paper, we extend this body of work to incorporate the notions of event-types and space-types. Teaching events have multiple ‘event-types’, such as lecture, tutorial, workshop, etc., and there are generally corresponding space-types. Matching the type of an event to a room of a corresponding space-type is generally desirable. However, realistically, allocation happens in a mixed space-type environment where teaching events of a given type are allocated to rooms of another space-type; e.g., tutorials will borrow lecture theatres or workshop rooms. We propose a model and methodology to quantify the effects of space-type mixing and establish methods to search for better space-type profiles; where the term “space-type profile” refers to the relative numbers of each type of space. We give evidence that these methods have the potential to improve utilisation levels. Hence, the contribution of this paper is twofold. Firstly, we present informative studies of the effects of space-type mixing on utilisation, and critical utilisations. Secondly, we present straightforward though novel methods to determine better space-type profiles, and give an example in which the resulting profiles are indeed significantly improved. <br/

    Post enrolment based course timetabling: a description of the problem model used for track two of the second International Timetabling Competition

    Get PDF
    In this paper we give a detailed description of the problem model used in track-two of the second International Timetabling Competition, 2007-2008 www.cs.qub.ac.uk/itc2007/). This model is an extension of that used in the first timetabling competition, and we discuss the rationales behind these extensions. We also describe in detail the criteria that are used for judging solution quality and discuss other issues that are related to this. Finally we go over some of the strengths and limitations of the model. This paper can be regarded as the official documentation for track-two of the timetabling competition

    An online learning selection hyper-heuristic for educational timetabling

    Get PDF
    Examination and course timetabling are computationally difficult real-world resource allocation problems. In 2007, an International Timetabling Competition (ITC) consisting of three classes: (i) examination timetabling, (ii) post enrollment-based, and (iii) curriculum-based course timetabling was organised. One of the competing algorithms, referred to as CPSolver, successfully achieved the first place in two out of these three tracks. This study investigates the performance of various multi-stage selection hyper-heuristics sequencing low-level heuristics/operators extending the CPSolver framework which executes hill climbing and two well-known local search metaheuristics in stages. The proposed selection hyper-heuristic is a multi-stage approach making use of a matrix which maintains transitional probabilities between each low-level heuristic to select the next heuristic in the sequence. A second matrix tracks the probabilities of ending the sequence on a given low-level heuristic. The best configuration for the selection hyper-heuristic is explored tailoring the heuristic selection process for the given timetabling problem class. The empirical results on the ITC 2007 problem instances show that the proposed selection hyper-heuristics can reduce the number of soft constraint violations, producing improved solutions over CPSolver as well as some other previously proposed solvers, particularly, in examination and curriculum-based course timetabling
    corecore