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Engineering Systems Integration
unencumbered measures mentioned has a masking effect on the meaning of
the measure. The degree to which that masking effect can be quantified in a
period and averaged somewhat mitigates the masking effect if that period is
meaningful in the context of the overall usefulness of using the measure as
the primary indicator for determining progress or for estimation purposes.
Because although tests can be developed to “measure” the proficiencies of
the engineers for their statistical weightings, coercive effects complicate the
use of rework as a measure. Such tests of proficiency, for example, may be
applicable to software, but not to building physical entities. Whereas source
lines of code or function points (to mention a few) have been used to estimate
software work efforts, using rework metrics may provide supplemental, supporting evidence that proves useful in some circumstances. Previous works
on physical structures and computer hardware also have various methods
and measures to estimate work. Combined with other such measures of
rework, the totality of measures may be sufficient to perform the necessary
comparisons for planning.
Lifecycle Measure: Time
A lifecycle stage is characterized as a distinct period within a sequence of
stages. Each stage is a conglomerate of periods of activities. Time can be considered a limitation that bounds the period between the notional onset of life
and the somatic moment of death of an entity. Time can also be regarded as
a constraint that restricts what is available within the defined limits. Each
stage can be constrained in different ways, for example, by budget, schedule,
available skills, and allocations of office space (for example).
A condition for lifecycle success requires the individual summation of each
type of constraint not exceed the limitation imposed on the type. In other
words, lifecycle success means not overrunning budgets or not exceeding
timetables to deliver the expected product. With regard to a limitation, time
refers to that of the lifecycle, and in the context of a constraint, time refers to
that apportioned to each stage (or that which is allocated to an activity within
a stage). Time is a consummate, independent measure of a cycle.
Lifecycle Measure: Cost
Cost is a measure of what is expended to attain or accomplish something.
Cost is the total of expenses that it takes to provide the totality of a product
or a portion of the product, within the context of the product’s lifecycle
(e.g., a stage or total lifecycle). Cost can also be construed as a constraint
within defined limits of an overall budget that is imposed on a stage or an
assemblage of stages. In this context, cost takes on the notion of “budget”—
the allocation of cost for a particular time or purpose. Budgets can be allocated to each stage and expenditures monitored against those budgets.
Engineering Systems Integration
unencumbered measures mentioned has a masking effect on the meaning of
the measure. The degree to which that masking effect can be quantified in a
period and averaged somewhat mitigates the masking effect if that period is
meaningful in the context of the overall usefulness of using the measure as
the primary indicator for determining progress or for estimation purposes.
Because although tests can be developed to “measure” the proficiencies of
the engineers for their statistical weightings, coercive effects complicate the
use of rework as a measure. Such tests of proficiency, for example, may be
applicable to software, but not to building physical entities. Whereas source
lines of code or function points (to mention a few) have been used to estimate
software work efforts, using rework metrics may provide supplemental, supporting evidence that proves useful in some circumstances. Previous works
on physical structures and computer hardware also have various methods
and measures to estimate work. Combined with other such measures of
rework, the totality of measures may be sufficient to perform the necessary
comparisons for planning.
Lifecycle Measure: Time
A lifecycle stage is characterized as a distinct period within a sequence of
stages. Each stage is a conglomerate of periods of activities. Time can be considered a limitation that bounds the period between the notional onset of life
and the somatic moment of death of an entity. Time can also be regarded as
a constraint that restricts what is available within the defined limits. Each
stage can be constrained in different ways, for example, by budget, schedule,
available skills, and allocations of office space (for example).
A condition for lifecycle success requires the individual summation of each
type of constraint not exceed the limitation imposed on the type. In other
words, lifecycle success means not overrunning budgets or not exceeding
timetables to deliver the expected product. With regard to a limitation, time
refers to that of the lifecycle, and in the context of a constraint, time refers to
that apportioned to each stage (or that which is allocated to an activity within
a stage). Time is a consummate, independent measure of a cycle.
Lifecycle Measure: Cost
Cost is a measure of what is expended to attain or accomplish something.
Cost is the total of expenses that it takes to provide the totality of a product
or a portion of the product, within the context of the product’s lifecycle
(e.g., a stage or total lifecycle). Cost can also be construed as a constraint
within defined limits of an overall budget that is imposed on a stage or an
assemblage of stages. In this context, cost takes on the notion of “budget”—
the allocation of cost for a particular time or purpose. Budgets can be allocated to each stage and expenditures monitored against those budgets.