Decision Optimization

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CP Tardiness in permutation flowshop scheduling

  • 1.  CP Tardiness in permutation flowshop scheduling

    Posted Mon May 17, 2021 04:13 PM
    Hello everyone,

    I am new in CP. I am trying a flow shop scheduling program to calculate tardiness. I cannot get an exact result. Do you have any hints for me? The code and data are below. Thanks. 

    Hermilio Vilarinho
    =======================================================================================================================
    using CP;

    //Parameters
    int nJobs=...;
    range Jobs=1..nJobs;
    int nMachines=...;
    range Machines=1..nMachines;
    int Duration[Machines][Jobs]=...;
    int Due_Date[Jobs]=...;


    //Decision variables
    dvar interval Process[j in Jobs][m in Machines] size Duration[m][j];
    dvar sequence Seqm[m in Machines] in all(j in Jobs) Process[j][m];


    execute {
    cp.param.TimeLimit = 3600;
    }

    //Objective Function

    dexpr int Tardiness[j in Jobs] = maxl(0, endOf(Process[j][nMachines])-Due_Date[j]);
    minimize sum (j in Jobs) Tardiness[j];

    //Constraints
    subject to {

    forall (m in Machines)
    noOverlap(Seqm[m]);

    forall (j in Jobs, o in 1..nMachines-1)
    endBeforeStart(Process[j][o], Process[j][o+1]);

    };
    ==================================================================================================================
    nJobs=20;
    nMachines=5;



    Duration=[[54 83 15 71 77 36 53 38 27 87 76 91 14 29 12 77 32 87 68 94],
    [79 3 11 99 56 70 99 60 5 56 3 61 73 75 47 14 21 86 5 77],
    [16 89 49 15 89 45 60 23 57 64 7 1 63 41 63 47 26 75 77 40],
    [66 58 31 68 78 91 13 59 49 85 85 9 39 41 56 40 54 77 51 31],
    [58 56 20 85 53 35 53 41 69 13 86 72 8 49 47 87 58 18 68 28]];

    Due_Date=[300 300 300 300 300 500 500 500 500 500 1000 1000 1000 1000 1000 1200 1200 1200 1200 1200];


    ------------------------------
    [Hermilio] [Vilarinho]
    ------------------------------

    #DecisionOptimization


  • 2.  RE: CP Tardiness in permutation flowshop scheduling

    Posted Tue May 18, 2021 02:34 AM
    Edited by System Fri January 20, 2023 04:16 PM
    Duplicate of : this question


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    Philippe Laborie
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