Lecture 6
Panning and control is concerned with the activities that attempt to reconcile the demands of the market and the ability of the operations resources to deliver
Planning is a formalization of that is intended to happen at some time in the future, Control is the process of coping with change (customers changing their minds about what they want or when they want it etc.)
Long term planning and control
Short term planning and control
Medium term planning and control
Determines resources in aggregated form
Objectives set in largely financial terms
Uses aggregated demand forecasts
Uses partially disaggregated demand forecasts
Determines resources and contingencies
Objectives set in both financial and operations terms
Uses totally disaggregated forecasts or actual demand
Makes interventions to resources to correct deviations from plans
Ad hoc consideration of operations objectives.
Planning and control activities
Sequencing determines the priority of work, when it will be tackled etc. The priorities to work are determined by some set of rules.....
Scheduling. Having determined the sequence that work is to be tackled in, some operations require a detailed timetable showing what time/date jobs start, and when they should end (Forward involves starting work a soon as it arrives. Backward involves starting jobs last possible moment to prevent products being late)
Loading is the amount of work that is allocated to a work centre
Monitoring and controlling, Each part of the operation now has to be monitored to ensure that planned actives are indeed happening
Finite loading is an approach which only allocates work to a work center up to a set limit. Is important where, it is necessary to limit the load (luggage on aircraft), it is possible to limit the load (appointment system for a hairdresser)
Infinite loading an approach to loading work which does not limit accepting work, but instead tries to cope with it. Useful when, not possible to limit load (accident and emergency department in hospital), it is not necessary to limit load (fast food outlets, flexible capacity to deal with varying arrival rates)
Customer priority , some businesses will allow an important or aggrieved customer, or item to be process prior to others, irrespective or the order of arrival. (Hotels complaining customers, Banks rich individuals)
Due date, means when work is sequenced according to when it is due for delivery, irrespective of the size of each job or the importance for the customer
First in first out (FIFO), First come first serve mentality (any normal queuing system, next person who waited the longest will be next in line)
Push system is where material is moved onto the next stage as soon as it has been processed in the stage before, Pull system is whereby material is moved only when the next stage wants it
Pull schedules generally have far lower inventory levels and push scheduels