forecasting and inventory calculation
Exercise Problems for Chapter 5
Numerical example on page 203
|
Period |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
|
Month |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
|
Demand |
10 |
62 |
12 |
130 |
154 |
129 |
88 |
52 |
124 |
160 |
238 |
41 |
A = $54 r = $0.02/month v = $20/box
Decide on replenishment time and quantities for the above problem using the solution approaches listed below and calculate carrying and setup costs, as well as total cost for each approach.
a) 3-months’ demand replenishment
b) Fixed EOQ
c) Wagner-Whitin algorithm
d) Silver-Meal algorithm
e) Periodic order quantity
f) Lot-for-lot
g) Least unit cost
h) Part-period balancing
Toy Problem
|
Period |
1 |
2 |
3 |
4 |
|
Demand |
100 |
75 |
175 |
200 |
A = $50 v = $5 r = $0.01/month
Decide on replenishment time and quantities for the above problem using the solution approaches listed below and calculate carrying and setup costs, as well as total cost for each approach.
a) 3-months’ demand replenishment
b) Fixed EOQ
c) Wagner-Whitin algorithm
d) Silver-Meal algorithm
e) Periodic order quantity
f) Lot-for-lot
g) Least unit cost
h) Part-period balancing
Problem 5.2
The demand pattern for a type of filter is given below. These filters cost the company $4.75 each; ordering and carrying costs are $35 and $0.24/yr, respectively. Use the Silver-Meal heuristic to determine the sizes and timing of replenishment of stock.
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
July |
Aug |
Sep |
Oct |
Nov |
Dec |
|
18 |
31 |
23 |
95 |
29 |
37 |
50 |
39 |
30 |
88 |
22 |
36 |
Problem 5.10
Consider a company facing a demand pattern provided below. Each item costs $4.00. Ordering cost is $25 per order and carrying inventory costs the company $0.05/month. Using a 3-month decision rule total replenishment cost of the company is $256.
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
July |
Aug |
Sep |
Oct |
Nov |
Dec |
|
20 |
40 |
110 |
120 |
60 |
30 |
20 |
30 |
80 |
120 |
130 |
40 |
a) Construct a replenishment schedule and calculate the associated costs using the fixed EOQ method.
b) Repeat using Wagner-Whitin algorithm
c) Repeat using Silver-Meal heuristic
d) Repeat using LUC.
e) Repeat using PPB.