2. Continuous improvement is based on two major
ideas:
1) systematic (or scientifically based) improvement
2) iterative improvement.
3. Systematic Improvement
• Improvements are derived from use of a
scientific approach (and tools) and a structure
for team or individual effort.
• It considers a variety of possible solutions until
the best—not just the most obvious—is
identified factually.
• Having made a first step at improvement using
these methods, the methods can be repeated
to get continuous improvements.
4. • WV model to explain the concepts relating to
improvement as a problem-solving process.
• It is an aid to understanding and remembering
generally used stages of quality improvement and
quality maintenance.
• It also conveys the idea of moving systematically
back and forth between abstract thought and
empirical data during the process of solving a
problem.
• it is an abstraction and idealization, useful for
figuring out where you are and where you need
to go next.
5. • The WV model depicts the overall form of
problem solving as alternation between
• thought (ruminating, planning, and analyzing) and
• experience (getting information from the real
world, e.g., through interviews, experiments, or
numerical measurements).
• The path between these two levels over time
forms the shape of a W and then a V hence, the
name WV.
6. • you sense a problem and then collect data on
where it might be;
• choose a specific improvement activity and then
collect data on exactly what is wrong;
• plan a solution and then collect data to be sure it
works; and
• then standardize on the new solution.
7. Three Types of Improvement
• In addition to illustrating the interplay between
thought and experience, the WV model illustrates
three basic types of problem solving, as shown in
Figure
8. • The three types of improvement are described
below:
1) Process Control,
2) Reactive Improvement, And
3) Proactive Improvement.
• Quality management started with process control
in the United States in the 1930s and in Japan in
the 1950s.
• Reactive improvement was added in the 1960s
and 1970s, followed by
• Proactive improvement in the 1980s.
9. Process control
• Suppose a worker is charting her process with
a control chart, such as the one shown below.
In Figure , results of a process are plotted from
left to right over time;
• the resulting chart highlights those results
that exceed certain limits of acceptability
10. • If the process produces results that are out of its
control limits, the worker takes corrective action.
• This cycle, known as the SDCA (standard, do,
check, act) cycle, is shown in the rough shape of a
V in Figure
11. • Thus, the method is to have a standard process, to
use it to check whether the product meets the
specification, and
• then to act to bring the process back to the
standard.
• The concept is depicted as a cycle because one
continues to apply the standard as long as the
production procedure continues.
• This cycle to control or maintain the operation of
a good process is known as process control.
12. Reactive improvement
• The next stage of the WV model addresses the
improvement of a weak process.
• Suppose you have a specific process that
produces results that simply aren’t good enough
(Figure)—there are many points outside the
control limits.
13. • Suppose, even if the worker corrects the
process according to the process manual, the
process repeatedly produces results that are
out of its control limits.
• There is obviously something wrong with the
process.
• In this case, the worker must take data,
analyze the data, find the root causes of the
problem, and implement appropriate
countermeasures.
14. • These steps, designated the 7 steps in this book,
are a standard methodology for improving weak
processes. This approach is known as reactive
improvement because it reacts to already
existing weaknesses.
15. Proactive improvement
• In many situations you do not start with a clear
idea of a specific needed improvement.
• Rather, you have to choose a direction for the
company before starting an improvement activity.
• For instance, you may need to decide what the
customer wants, which product to develop, or
which process needs improvement most.
• This situation is addressed by the final portion of
the WV model, known as proactive improvement
16.
17. Iterative Improvement
• Implicit in the WV model is the idea of
iterative improvement—the cycling back to
work on the next problem or the continued
improvement of an already improved process.
• This is the famous PDCA (plan, do, check, act)
cycle
18. • Plan: Determine analytically and quantitatively
what the key problems are with an existing
process or existing activities and how they might
be corrected.
• Do: Implement the plan.
• Check: Confirm quantitatively and analytically
that the plan works and results in improved
performance.
• Act: Modify the previous process appropriately,
document the revised process, and use it.
