Inventory Control

1
Inventory Control

• Basic Knowledge
• By Kawinthorn Saicharoen

2
Production Systems

• Engineering to Order
• Make to Order
• Assembly to Order
• Make to Stock

3
Inventory Systems

• Continuous Review
• Periodic Review
• Material Requirement Planning
• Distribution Requirement Planning
• Single Order Quantity

4
Inventory Investment

• Inventory Turnover
• Period of supply

5
Inventory Turnover Ratio
???????????????????????????? ?????????????????????
??????????????????????????????????????????????? ??
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??? ?????????????????????????????????
6
Demand
Product life cycle Type of demand Forecasting
technique
7
Product Demand Life Cycle
Saturation / maturation
Birth
Growth
decline
8
Demand Type
Quantitative 1. Constant/Variable 2.
Independent / Dependent
Qualitative Expert persons Customer Surveys
9
Demand Forecasting
Quantitative
Qualitative
Objective
Subjective
Statistical
Judgmental
10
Demand Forecasting
Quantitative Demand
Time Series Analysis
Horizontal
Trend
Pattern of Data
Season
Cycle
11
Demand Forecasting
Quantitative Demand
Time Series Analysis
Mean Absolute Deviation
Accuracy
Mean Sum of Square Error
12
Demand Forecasting
Quantitative Demand
Time Series Analysis
????????????????
Moving Average
Exponential Smoothing
13
Inventory Cost
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14
Item Cost ????????????
???????????? ??? ???????????????????????????
???????????????????????? ???????
???????????????????? ??????????????????????????
??????????
15
Holding Cost

• ????????????????????
• ????????????????????????????? 4 ???????
• ???????????????(Capital Cost)
• ?????????????????????????????(Inventory Service
  Cost)
• ???????????????????????????????????(Storage Space
  Cost)
• ??????????????????????????????(Risk Cost)

16
Holding Cost
???????????????(Capital Cost)

• ????????????????????????????????????????
  ?????????????????????
• ???????????????????????????? 2 ???????? ?????
  ?????????
• ?????????????????????????????????????????????????

17
Holding Cost
?????????????????????????????(Inventory Service
Cost)
???????????????????????????????????????????
???? ????????????????? (????????????????????) ????
?????????????????? ?????????? ????
18
Holding Cost
???????????????????????????????????(Storage Space
Cost)

• ???????????????????????????????????????????
  ???????? ???????
• ???????????????????? 4 ???????
• ???????????????????????????
• ?????????????????
• ???????/????????
• Company-owned (Private) Warehouse

19
Holding Cost
??????????????????????????????(Risk Cost)

• ????????????????? 4 ??????
• ????????????????(Obsolescence)
• ???????????????????
• ?????????????????
• ??????????????????????????????????????????

20
Shortage Cost
???????????????????????
?????????????????????????????????????????????????
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? ????????????????????????????????????????????????
?????
21
Setup Cost
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