上海交通大学：《生产计划与控制 Production Planning and Control》课程教学资源（课件讲稿）chap03 Aggregate Planning ?Introduction ?Aggregate Units of Production; ?Costs in Aggregate Planning; ?A Prototype Problem;

③ Production Planning and Control Professor JIANG Zhibin Dr.GENG Na Department of Industrial Engineering Logistics Management Shanghai Jiao Tong University

Production Planning and Control Professor JIANG Zhibin Dr. GENG Na Department of Industrial Engineering & Logistics Management Shanghai Jiao Tong University

Production and Operation Managements Chapter 3 Aggregate Planning Dr Na genG Department of Industrial Engineering Management Shanghai Jiao Tong University

Production and Operation Managements Dr Na GENG Department of Industrial Engineering & Management Shanghai Jiao Tong University Chapter 3 Aggregate Planning

Content of this course Scheduling in Supply Forecast of future demand Chain Management Transportation problem Aggregate plan Master production schedule (MPS) Project Scheduling Schedule of production quantities by Subject to known and product and time period unknown demand Material Requirement Planning(MRP) Inventory Control Generate production orders and Subject to known and purchase order unknown demand Operations Scheduling Push and Pull Production To meet quantities and time Control Systems requirements for MRP JIT

Content of this course Forecast of future demand Aggregate plan Master production schedule (MPS) Schedule of production quantities by product and time period Material Requirement Planning (MRP ) Generate production orders and purchase order Operations Scheduling To meet quantities and time requirements for MRP Inventory Control Subject to known and unknown demand Push and Pull Production Control Systems JIT Project Scheduling Subject to known and unknown demand Scheduling in Supply Chain Management Transportation problem

Chapter 3 Aggregate Planning Contents .Introduction Aggregate Units of Production; .Costs in Aggregate Planning; A Prototype Problem; Solution of Aggregate Planning Problem by LP

Chapter 3 Aggregate Planning Contents •Introduction •Aggregate Units of Production; •Costs in Aggregate Planning; •A Prototype Problem; •Solution of Aggregate Planning Problem by LP

Introduction Aggregate planning (AP),also called macro planning,decides how many employees the firm should retain and,for a manufacturing firm,the quantity and the mix of products to be produced. Macro planning strategies are a fundamental part of the firm's overall business strategy

Introduction • Aggregate planning (AP), also called macro planning, decides how many employees the firm should retain and, for a manufacturing firm, the quantity and the mix of products to be produced. • Macro planning strategies are a fundamental part of the firm’s overall business strategy

Introduction AP begins with the forecast of demand Assumption for AP:demand is deterministic,or known in advance. The assumption is made to simplify the analysis and allow us to focus on the systematic or predictable changes in the demand pattern

Introduction • AP begins with the forecast of demand. • Assumption for AP: demand is deterministic, or known in advance. • The assumption is made to simplify the analysis and allow us to focus on the systematic or predictable changes in the demand pattern

Introduction Aggregate planning involves several basic competing objectives. Make frequent and large changes in size of labor force:a chase strategy to react quickly to anticipated changes in demand,cost effective,but a poor long-term strategy; Retain a stable workforce:results in larger buildups of inventory during period of low demand; Develop a production plan for a firm to maximize profit over the planning horizon subject to constraints on capacity. AP methodology is designed to translate demand forecast into blueprint for planning staffing and production level for a firm over a predetermined planning horizon;

Introduction • Aggregate planning involves several basic competing objectives.  Make frequent and large changes in size of labor force: a chase strategy to react quickly to anticipated changes in demand, cost effective, but a poor long-term strategy;  Retain a stable workforce: results in larger buildups of inventory during period of low demand ;  Develop a production plan for a firm to maximize profit over the planning horizon subject to constraints on capacity. • AP methodology is designed to translate demand forecast into blueprint for planning staffing and production level for a firm over a predetermined planning horizon;

Chapter 3 aggregate Planning Contents .Introduction Aggregate Units of Production; .Costs in Aggregate Planning; .A Prototype Problem; .Solution of Aggregate Planning Problem by LP

Chapter 3 Aggregate Planning Contents •Introduction •Aggregate Units of Production; •Costs in Aggregate Planning; •A Prototype Problem; •Solution of Aggregate Planning Problem by LP

Aggregate Units of Production AP is predicated on the existence of an aggregate unit of production. Describe aggregate units in the following situations: In terms of"average'item-when the items produced are similar,e.g.cars,computers, In terms of weights (tons of steel),volume (gallons of gasoline),amount of work required(worker-years of programming time),and dollar value(value of inventory in dollars)-when many kinds of items are produced; Appropriate aggregating schema are determined by context of the particular planning problem and the level of the aggregation to be required

Aggregate Units of Production • AP is predicated on the existence of an aggregate unit of production. • Describe aggregate units in the following situations:  In terms of “average’ item-when the items produced are similar, e.g. cars, computers;  In terms of weights (tons of steel), volume (gallons of gasoline), amount of work required (worker-years of programming time), and dollar value (value of inventory in dollars)-when many kinds of items are produced; • Appropriate aggregating schema are determined by context of the particular planning problem and the level of the aggregation to be required

Aggregate Units of Production Example 3.1:Decide on aggregating schema for the manager of a plant that produces six models of washing machines to determine the workforce and production levels. Number of Worker- Hours Required to Selling Price Sales Model Number Rate(%) Produce A5532 4.2 285 32 K4242 4.9 345 21 L9898 5.1 395 17 L3800 5.2 425 14 M2624 5.4 525 10 M3880 5.8 725 6

Aggregate Units of Production Example 3.1: Decide on aggregating schema for the manager of a plant that produces six models of washing machines to determine the workforce and production levels. Model Number Number of Worker￾Hours Required to Produce Selling Pric e Sales Rate(%) A5532 4.2 285 32 K4242 4.9 345 21 L9898 5.1 395 17 L3800 5.2 425 14 M2624 5.4 525 10 M3880 5.8 725 6