1. Planning in production systems Operation scheduling Slovak University of Technology Faculty of Material Science and Technology in Trnava

2. Operation scheduling the lowest level of planning detailed description of that, what would be produced, when and on which machines

3. Heuristic methods: they are not optimizing methods these methods in majority of cases find suitable solution, which suits to limiting conditions it is not obvious, to what extent the solution is good, because optimal solution is not known they are based on experiences, using knowledge from some previous action

4. Main aims of scheduling maximum utilization of machines maximum degree of completion and minimal continuous time minimize of inaccuracy function

5. Scheduling objectives 1. assign operations to production facilities – entering into production with aim to design a removal profile of capacity units Two basic approaches: forward loading backward loading 2. to define processing order of individual products in process of production – sequencing

6. Forward loading it starts with actual point in time, products are assigned to workplaces towards future on the workplaces the capacity demands which are under consideration time periods are cumulated; it is possible to consider of final or unlimited workplace capacity time scheduling horizon could be overrun – no fulfilment of product delivery time

7. Backward loading products are starting to assign into workstations from the term of their eduction backwards, in actual term, assigning starts at latest possible term, minimalization of working out, short continual periods it is possible to over step capacity border of workplace terms of overrun are not over stepped

8. Assignation order of processing production task it is necessary to define superior selection rule – according it the products are chosen from line and are assigned to working places it is necessary to assign rule for choice of machine, that performs right operation

9. Hand made Gantt diagram - forward loading

10. Hand made Gantt diagram - backward loading

11. Techniques and methods of scheduling Conventional methods  Mathematical programming approaches – linear programming, dynamic programming  Heuristically oriented approaches New methods  Techniques of artificial intelligence and knowledge systems  Techniques with use of neuron nets  Techniques with use of modeling and simulations

12. Place of scheduling in PPS systems Source requests of plan Aggregate production planning Rough capacity planning Operation planning Capacity requests of plan Material requests of plan input/ output analysis Workshop system of scheduling Dynamic management Offer management

13. Required input and output information Input informationOutput information Production planInput in production Products structure, componentsProduction order Production procedure, operationsWorking sheets Technologies used, production sources Production currency Working sources Calendar of changes