TOBB ETÜ 2014-2015 Spring Semester
END 307- Production Systems Planning
Assignment 7
Assignment Date: 21.03.2015, Submission Date: 26.03.2015
Q1. A small bicycle manufacturer produces two types of bicycles (Model A and D). The
BOM for the bicycles are given below;
D
A
X
F(2)
K(2)
F
F
W(3)
The numbers within parenthesis represent the number of components needed for one parent
component. The demand forecasts for Model A in each week are 40+(FactorX x20) bicycles for
weeks 7, 8, 9, 10 and 11. The demand forecasts for Model D is 25+(FactorX x10) bicycles for the
same weeks. On hand inventory, scheduled receipts, lead times and lot sizing rule for the
components are given below (always round the terms involving FactorX to nearest integer) ;
Name
A
D
X
W
F
K
Scheduled
Inventory on
receipts
hand at week 1
20+(FactorXx5)
5
in (week 3),
20+(FactorXx10)
in (week 4)
15+(FactorXx10)
5
(week 2)
--5
----2
(FactorXx15) in
10
(week 2)
--10
Lead time
(Week)
2
Lot sizing rule
lot-for-lot
1
lot-for-lot
1
2
1
Lot size=40 and its multiples
lot-for-lot
lot-for-lot
1
Lot size= requirements of next
2 weeks
(a) Produce the MPS for model A and D.
(b) For each component find out the MRP plan (Note: Component F takes place in both BOMs
and at different levels. Sum up the requirements for F and construct the MRP for F at level 2.)
(c) For component W, the setup cost is (50+FactorXx15) TL and the inventory holding cost per
week per unit is 1,25 TL. Find the lot sizing solutions for W using;
 Siver-Meal
 Least unit cost
 EOQ approach
and calculate the total cost for each solution.
(d) Draw the network to represent the lot sizing problem in item c.
Q2. Fill in the blanks (lengths of the blanks are not exactly in line with the lengths of the fill-ins)
The main input that drives the MRP process is ………………………., which is simply . . .
and the main outputs of MRP are ……
Scheduled receipts in MRP is defined as ………..
Having large lot sizes in upper level components in the BOM leads in to ……………
….…………….….…… which makes production scheduling difficult for lower level components.
In my opinion the most important two weaknesses of MRP are ……
Main modules of an ERP system are ………….. . . Success of an ERP system in a company directly
depends on ……………………..