Makespan is a criterion generally used in classical literature for scheduling. We have been exposed to job shop or flow shop scheduling wherein makespan is widely used in many of the popular algorithms. In today's hyper competitive world makespan may not be relevant, however scheduling according to the dynamic needs of the customer might. Your on this issue views are sought.
A modern production in today’s world is characterized in an increasing extend by low stocks, short throughput time and, in some cases, even one-piece-flow. So, with increasing dissemination of these developments, the pool from which you can select orders for scheduling is constantly decreasing. So equally the effectiveness and meaning of scheduling in an overall view is declining.
Consider for example a JIS-supplier in the automotive industry in his build-to-order situation. Between the moment of order income and the due time there are only a few (4 to 6) hours which means very limited possibilities to deviate from FCFS. – These structures started to exist about 20 years ago as you need a sophisticated information link and a very reliable logistic connection. Today you find this type of production increasingly in other industries as e.g. electronics where computers a built custom made for the client within one day.
In build-to-stock industry the situation to my mind looks different as you have much more time. But here you generally have a waiting queue of orders in front of every machine. So pointing at capacity utilization with your scheduling will be of no use as you already use your machines at a rate as high as technically possible. There might be an effect on the throughput time of your orders, which I would expect to be negligible. – In case of order-dependant setup-times it seems to be much more appropriate to focus these as your scheduling criteria as you can win additional production time.
Even though makespan is a popular measure of performance and so as tardiness and earliness criterion, all of these measures are basically profit driven. However in modern production industries, performance of a production system depends on several factors like carbon emissions, environmental impacts. So,Scheduling considering only profit driven factors is too restrictive.
- Badges
- Science topic
- Similar topics
- Linguistics
- Composition Studies
- Publication