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Planning of paint production Description Planning of paint production:
- linear, 'element', 'implies', and 'all-different' constraints (b5paint_ka.mos).
- Alternative formulation using 'disjunctive' and 2-dimensional 'element' constraints (b5paint2_ka.mos).
- Third model version (b5paint3_ka.mos) using 'cycle' constraint.
- Forth model formulation (b5paint4_ka.mos) as disjunctive scheduling problem with setup times, modeled with task and resource objects, using 'equiv', 'element', 'maximum' constraints and defining an enumeration strategy based on tasks and variables.
Further explanation of this example:
'Xpress Kalis User Guide', Section 3.8 implies: Paint production
Source Files Data Files b5paint_ka.mos (!****************************************************** CP Example Problems =================== file b5paint_ka.mos ``````````````````` Planning of paint production (See "Applications of optimization with Xpress-MP", Section 7.5 Paint production) (c) 2008 Artelys S.A. and Fair Isaac Corporation *******************************************************!) model "B-5 Paint production (CP)" uses "kalis" declarations NJ = 5 ! Number of paint batches (=jobs) JOBS=1..NJ DUR: array(JOBS) of integer ! Durations of jobs CLEAN: array(JOBS,JOBS) of integer ! Cleaning times between jobs CB: array(JOBS) of integer ! Cleaning times after a batch succ: array(JOBS) of cpvar ! Successor of a batch clean: array(JOBS) of cpvar ! Cleaning time after batches y: array(JOBS) of cpvar ! Variables for excluding subtours cycleTime: cpvar ! Objective variable end-declarations initializations from 'Data/b5paint.dat' DUR CLEAN end-initializations forall(j in JOBS) do 1 <= succ(j); succ(j) <= NJ; succ(j) <> j 1 <= y(j); y(j) <= NJ end-do ! Cleaning time after every batch forall(j in JOBS) do forall(i in JOBS) CB(i):= CLEAN(j,i) clean(j) = element(CB, succ(j)) end-do ! Objective: minimize the duration of a production cycle cycleTime = sum(j in JOBS) (DUR(j)+clean(j)) ! One successor and one predecessor per batch all_different(succ) ! Exclude subtours forall(i in JOBS, j in 2..NJ | i<>j) implies(succ(i) = j, y(j) = y(i) + 1) ! Solve the problem if not cp_minimize(cycleTime) then writeln("Problem is infeasible") exit(1) end-if cp_show_stats ! Solution printing writeln("Minimum cycle time: ", getsol(cycleTime)) writeln("Sequence of batches:\nBatch Duration Cleaning") first:=1 repeat writeln(" ", first, strfmt(DUR(first),8), strfmt(getsol(clean(first)),9)) first:=getsol(succ(first)) until (first=1) end-model | |||||||||

Copyright 2017 Fair Isaac Corporation. |