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WBS is nothing but Work Breakdown Structure. It is mainly used in Project System (PS) module. Tcode: CJ20N. For any project defined we must have atleast one WBS. Within this WBS we can have networks. Networks are nothing but the series of activities. Material are used to perform the activities.
Manufacturing execution systems (MES) are computerized systems used in manufacturing. MES track and document the transformation of raw materials through finished goods.MES can provide the right information at the right time and show the manufacturing decision maker how the current conditions on the plant floor can be optimized to improve production output..ndustry groups such as MESA International-- Manufacturing Enterprise Solutions Association were created in the early 1990's in order to address the complexity, and advise on execution, of MES Systems.