Page 462 - Design for Six Sigma for Service (Six SIGMA Operational Methods)

420 Chapter Twelve

Project 1 A B CD E F G H I J 48 weeks

Project 2 A B CD E F G H I J 50 weeks
Project 3 A B CD E F G H I J 52 weeks
Resource 1
Resource 2
Resource 3
Figure 12.5 Three Software Development Projects, Multitasking

development time for all three projects, with exactly the same amount of
resources (programmers). Clearly, this example shows that the multitasking
practice slows down the project completion times, so it is a policy constraint.

Resource Constraints
Resource constraints are resource-related constraints. The resources are
usually machines, people, skills, and market. The market constraint means
that the market demand is less than the throughput of the process. According
to Woepple (2001), resource constraints are less common than policy con-
straints. Many times, policy constraints are mistaken as resource constraints.

Material Constraints
Material constraints involve a shortage of scarce material. According to
Woepple (2001), the material constraints are the least common. However,
they do happen occasionally. In the year 2003, some types of steel became
a scarce commodity for the automotive industry.

Project 1 AB C D E F G H I J 20 weeks
Project 2 AB C DE F G H I J 28 weeks

Project 3 AB C DE F G H I J 36 weeks

Resource 1
Resource 2

Resource 3
Figure 12.6 Three Software Development Projects, No Multitasking