Manufacturing planning and control systems (MPC)
What's the time span and related activities of short-term forecasting?
Couple of weeks to 3 months. For production management and material requirement: Planning purchase, job scheduling, work force level, job assignment, production level, cash requirement.
What is machine loading?
Jobs are allocated to machines in order to meet the due dates
What is a dependent demand (inventory)?
MRP uses planned production to get a timetable for material orders. Stocks of materials depend directly on the known demand. This kind of system is called a dependent demand. ie the inventory depends on known demand
What are the two strategies for aggregate production planning?
Maintaining uniform production rate, and maintain uniform workforce
What is an independent demand (inventory)?
The demand in an independent demand system is not directly related to the demand shown in a master production schedule, but is forecast from historical figures.
What is the difference between independent and dependent demand?
With independent demand systems, the stocks are not related to production plans, they must be higher. Stocks are reduced during production but they are replenished as soon as possible. Dependent demand inventory systems are most often used for raw materials. Independent demand inventory systems are most often used for finished goods.
What is forecasting?
An estimate of the level of demand expected in the future. It provides information for better decisions. It determines capacity requirements, such as size of plants, # of workers, and # of machines
What's the time span and related activities of medium-term forecasting?
3 months to one year. For later requirements of personnel, equipment, materials: Sales plan, production/capacity planning, cash budget, personnel level.
Define manufacturing system
A collection of people, equipment, and procedures organized to accomplish production operations in a manufacturing industry.
What is the ratio for capacity planning utilization?
Actual output over the designed capacity
Define explanatory forecasting
Based on econometric and system dynamic models
Define qualitative forecasting
Based on opinion, for intermediate and long-term forecasting
Define descriptive forecasting
Based on the analysis of historical data, quantitative methods.
What are the manufacturing support systems?
Business functions, product design, manufacturing planning, manufacturing control.
What is capacity planning?
Capacity planning aims to match available capacity to forecast demand. Excess capacity results in too much investment in facilities, not enough and some demand will not be met
What are the priority rules?
First come first serve (FCFS), shortest processing time (SPT), earliest due date (EDD), least slack (LS), least slack per operation (LSPO), critical ratio
What is material requirement planning?
Gives a detailed timetable for the delivery of material needed to support operations.
What is the primary objective of MPC?
Manufacture at the right time, in the right quantities, and meet quality and minimum cost
What are some forecasting methods?
Market survey, trend line, moving averages, exponential smoothing
What are the three goals of MPC?
Minimize cost, high quality, and minimum lead time
What's the time span and related activities of long-term forecasting?
One to five years. For general future of the company: Product, capacity changes, and plant location. Capital investment, new product, facility location, R&D expenditure, new market, strategic plan.
What is master production schedule?
The aggregate production plan levels the production schedule to minimize production costs but give no indication about how to deal with individual parts. Disaggregate to get the microscopic picture, this results in MPS
What are the three demand forecasting techniques?
Qualitative forecasting, explanatory, and descriptive.
What is job sequencing?
Sequence of each part through machines
What are the types of forecasting?
Short-term, medium-term, long-term
What does demand forecasting affect?
The types of products developed and marketed, the production facilities to be provided, the volume of output and inventory levels.
What is the critical ratio?
Time remaining until due date over the lead time remaining
What is the primary function of demand management?
To forecast the demand of product. Demand from forecasting is an input for aggregate production planning