The system was developed in C++ and  it uses memory resident architecture which means that the solution doesn’t use  hard drive during calculations and thus it has high performance. The system  uses for modeling constraint satisfaction programming algorithms including  linear and mixed integer programming, constraint-based search, heuristics and other  OR algorithms (Taha H., 2005).
The key results of the  implementation of the developed system are: significant rise in speed of  calculation (it takes minutes not hours now); improvement of schedule quality  thanks to detail modeling of steel making rules, application of contemporary  optimization algorithm and friendly user interface for manual changes of a  schedule. 

Results and discussion

The process of melt shop and caster  scheduling was completely renewed at Trinecke Zelezarny thanks to implementation  of the new solution. Today casting requirements are generated automatically  based on a valid calendar production plan. This allows a planner to work on the  complete calendar production plan horizon – up to 4 months. Currently melt shop  and caster schedules are created for 40 days. The first 14 days of the horizon  are planned in detail. The schedule is updated regularly based on real  situation in production. The visibility of schedules and wide planning horizon significantly  improved economic and technological reasonableness of planners’ decisions.
The result of new process implementation  was efficiency improvement not only in melting and casting but also at the  company in general. One of the key performance indicators of steelmaking is the  level of wasted tundish life at continuous casting.  An improvement of this indicator enables a  decrease in the costs of production, with simultaneous increase of the total  performance of the steel plant. The achievement of a good level for this  indicator is especially difficult due to the following factors: necessity to  produce a large variety of steel grades, taking into account special  requirements of individual customer orders; high share of small orders in proportion  to one heat, let alone to the minimal size of a tundish lot. The level of  wasted tundish life at continuous casting is evaluated as the difference  between the theoretical maximum and the planned sequence length for individual  steel grades, where the theoretical sequence length derives from the maximum length  of sequence given by the technology of production and the planned sequence length  derives from the casting schedule at the continuous casters. Statistics of average  tundish continuous casting is provided on Figure 6.