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Engineering Systems Integration
lose. The performance of the function of one car is in their instantaneous
speed or its acceleration. In this example of cars racing, the aggregate
human-construed object of “the two-car race” has a lifecycle. By chance if
the two cars were to collide with each other, they would interact through
EMMI. And further, if by chance the two cars ejected their drivers
unharmed, then burst into flames and burned as an aggregated mass, parts
of two cars might disintegrate, or fuse, or retain an individual similitude to
their precrash structures. Again, this event referred to as “crash” can be
described as an interaction, or should the resultant object take on properties, traits, and attributes different than those of the precombined objects,
then the “crash” can be described as an integration.
Quality
That functions may have a measurable performance and a loss attributable to
achieving that performance is inherent in the structure of objects. Quality
can be associated with the loss (Taguchi 1986, 1990; Taguchi et al. 2005). In
this manner, quality refers to the consistency of performance, or alternatively, the deviation from a target value (i.e., the performance requirement).
Quality indicates how well a function is accomplished by the system and is
a measure of the loss due to the performance of that function. Quality can be
represented as a loss function (Taguchi 1986; Taguchi et al. 2005) (see Chapter
6 and Appendix 2). The greater the loss resulting from the deviation from a
performance that is nominally the best, the poorer the quality. Overall, the
quality imputed to a set of objects characterizes the stability of the
performance(s) and the function(s) ascribed to that set of objects. The implications of poor stability relates to (1) nondelivery of the set of object’s functionality, (2) delivery of the set of object’s functionality (within the range of
performance tolerance), or (3) delivery of performance beyond the range of
specified performance tolerances. Functions describe the intentions of the
design. For functions, integration is the relationship between the mechanistic intentions expressed through the design and the performance of objects
through their EMMI.
The losses to achieve various performances are of two types—controllable
losses and uncontrollable losses. Controllable losses can be measured and
fairly determined to be associated with specific events. The losses due to
variation in performance are controllable to the point that variations due to
stochastic noise are controllable. Losses due to conversion efficiencies for
EMMI are controllable by the mechanisms of transformation of input EMMI
into output EMMI. If the mechanism for transforming EMMI is of a certain
type that results in a conversion efficiency (input/output) of say 80%, then
there is a 20% loss that does not translate into output performance. That 20%
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