Twelve tasks, with times and precedence requirements as shown in the following table, are to
be assigned to workstations using a cycle time of 1.5 minutes. Two heuristic rules will be tried:
(1) greatest positional weight, and (2) most following tasks.
In each case, the tiebreaker will be the shortest processing time.
Task
Length
(minutes)
Immediate
Predecessor
a 0.1 —
b 0.2 a
c 0.9 b
d 0.6 c
e 0.1 —
f 0.2 d, e
g 0.4 f
h 0.1 g
i 0.2 h
j 0.7 i
k 0.3 j
l 0.2 k
a. Draw the precedence diagram for this line.
b. Assign tasks to stations under each of the two rules.
c. Compute the percentage of idle time for each rule.