Inventory Management

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????? ????? Inventory Management
2
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• ???? ?????? ?????? ?????? ???? ???? ??? ???? ??
  ??? ???? ?????? ???????.

D. Sipper and R. L. Bulfin, Jr.,
Production Planning, Control, and Integration,
McGraw-Hill,1997.
3
(No Transcript)
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??? ?????? ?????????????? 1-3 2002
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• ???? 1999 ??"? ??????? ????? ????"? 1.37
  trillion
• 34 ??????
• 26 ???????
• 22 ????????.
• 8 ???? ???????.
• 10 ?????.

82 ???"?
7
Breakdown of the Total Investment in Inventories
in the U.S. Economy (1999(
S. Nahmias Production and Operations analysis
McGraw-Hill , 2002
8
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• ????? 1998 ?????? ????? ????????? 898 ???????
  ?? ???????? ????????? 10.6 ?????? ?????? ??????
  ( ??? ?? ??????? ????????? ???????? ???? )
• GDP - Gross Domestic Product
• 58 ??????.
• 38 ????.
• 4 ?????.

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  ????"? ?????? ????? ???? ???????.
• GM ?????? 26 ??????? ????? ???????? ???.

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• (WSJ, Oct 7, 1994)
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• (WSJ, August 1993)

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E(1)
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Average inventory 2 million???? ?????
Cost of goods sold 10 million???? ???? 52
business weeks per year?????? ????
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• ????? ????? ????? ?????
• Continues Review (Q) System
• ???? ????? ?? ????? ???? ???? (R) ??????
  (Order Level ) ???? ???? ????? (Q) - ???? EOQ
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• Periodic Review (P) System
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  S)).

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• Hybrid Systems
  Operational Replenishment System (S,s).
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  ?????? ( S ).

26
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Q
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Q/2
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34
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35
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??? ???? ??? ?????? Expected time between orders
????? ?????
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36
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80
ROP 14
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5
30
39
????? ?????? ????? EOQ

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