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Engineering Systems Integration
hydrogen, or by being pushed by another object, for example, the function’s
performance of the ‘to move’ function is zero. If the source of power is operative and has sufficient EMMI for the automobile’s mechanism to function
as designed and fulfill its tasks, then the object’s performance is said to be
measurable. Should there be a nominal value, m, that is expected as the measure of a function’s performance (under various conditions and circumstances) the performance is said to have a target performance value. If there
is a variation in performance that is characterized as distributed over a
small range of performances centered on the value for the target performance, then the target performance is regulated or controlled by a mechanism. By pressing down on the accelerator in the automobile, the performance
output of the car’s movement can be controlled according to the constraints
imposed by the design of the automobile and the allocations that result in
the various constraints. The variance in the output of the mechanism(s)
(termed as the variability in performance) for a given input (in this case
from the action of the driver (user) of the automobile driving the automobile) can be considered to be the quality of the function “to drive.” A function is describable in terms of its performances and its variability in
performance (quality) (Taguchi 1986). The functional boundaries of an
object are measurable by its performance(s) and its losses that result in
achieving those performances.
In addition to an object being recognizable by its physical boundaries and its
functional boundaries, the behavioral boundary of an object is determinable
by either the behaviors exhibited by the receiving object due to the influences
of receiving EMMI or in anticipation of the receiving EMMI. The behavioral
boundary of the sending object results from its influences due to either its
physical boundary or its functional boundary. This is to say that the sending
object has responsibility for its action(s) and that determining the results of
physical and functional boundaries is an important activity for integration.
Knowing the boundaries of the objects to be integrated helps delineate the
sequencing of objects for demonstration of functions. Recognizing that some
objects require multiple interfaces to demonstrate a top-level function demands
great care in building up all the subfunctions during the integration process.
No single object results in a function. A single object has no physical use
without some sort of connection (based on Type 1 or Type 2 interactions)
with another object. In general, that connection is through EMMI. The connection can be made physically with matter or remotely with energy, material wealth, or information. Each physical boundary is porous to energy,
material wealth, and information. The boundary is determined by various
connections between objects. The boundary conditions at an interface are
describable in terms of coupling, cohesion, abstraction, and granularity
(size of the increments of EMMI) of the EMMI that is transferred.
An automobile has the function of “travel” when the wheels are in contact
with road and they have sufficient traction with the surface of a road to the
car to move without the interface between the wheels and the road.
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