INTRODUCTION TO SOFTWARE DESIGN FOR SIX SIGMA (DFSS) - Software Design for Six-Sigma: A Roadmap for Excellence - page 192

order to optimize throughput and/or minimize processing costs. Software design for
reliability is discussed in Chapter 14.
When it is used for software testing, there is a large amount of savings in testing
time and cost. Design of experiments has been proven to be one of the best known
methods for validating and discovering relationships between CTQs (Y's) and
factors (x's).

8.8 OTHER DFSS APPROACHES

DFSS can be accomplished using any one of many other methodologies besides
the one presented in this topic. IDOV 24 is one popular methodology for designing
products to meet Six Sigma standards. It is a four-phase process that consists of
Identify, Design, Optimize, and Verify. These four phases parallel the four phases of
the ICOV process presented in this topic.

Identify phase: It begins the process with a formal tie of design to VOC. This
phase involves developing a team and a team charter, gathering VOC, performing
competitive analysis, and developing CTSs.
Design phase: This phase emphasizes CTSs and consists of identifying func-
tional requirements, developing alternative concepts, evaluating alternatives,
selecting a best-fit concept, deploying CTSs, and predicting sigma capability.
Optimize phase: The Optimize phase requires use of process capability infor-
mation and a statistical approach to tolerancing. Developing detailed design
elements, predicting performance, and optimizing design take place within this
phase.
Validate phase: The Validate phase consists of testing and validating the design.
As increased testing using formal tools occurs, feedback of requirements should
be shared with production operations and sourcing, and future operations and
design improvements should be noted.

Another popular Design for Six Sigma methodology is called DMADV, and it
retains the same number of letters, number of phases, and general feel as the DMAIC
acronym. The five phases of DMADV are:

Define: Define the project goals and customer (internal and external) require-
ments.
Measure: Measure and determine customer needs and specifications; benchmark
competitors and industry.
Analyze: Analyze the process options to meet the customer's needs.
Design: Design (detailed) the process to meet the customer's needs.
Verify: Verify the design performance and ability to meet the customer's needs.

24 See Dr. David Woodford's article at http://www.isixsigma.com/library/content/c020819a.asp.