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Systems Integration Management
descriptions of these knowledge points and the details of what and when
is expected as described in the systems engineering process models serve
to reinforce the result in the inevitable leanings toward iterative thinking
significantly past when recursive. For the most part, the systems engineering process models associate design verification with development and
system verification with integration. There is much overlap in how the various stages are defined in the numerous systems engineering process models,
so a definitive statement about when certain activities should occur is both
fruitless and perhaps misleading. The consequence is that many decisions
are left to the users of the systems engineering process models which
allows for the necessary tailoring to be accomplished based on the project
constraints, management preferences, and customer requests. The U.S.
Government Accountability Office and the systems engineering process
models reflect that integration is a work activity that fits within a domain
called development: as integration is related to bringing together objects as
part of the process of building a product or service. The integration framework (Chapter 2) captures that thinking using process management and
product and service deliverables.
The first phase of the Systems Process Model for Integration (SysPMI) is
the identification of objects (by pairs, where pairing of a single object with
another object always involves two other objects at a minimum) that are
required to demonstrate the top-level function(s), the subfunctions that support the top-level (end-to-end) functions, and the associated functional flow
block diagrams (at the pertinent level). The identification of the objects and
the match with functions is referred to as the mapping of functions to physical entities (or physical entities to functions). Additionally, the behaviors of
the users are associated with the functions and the physical objects. From the
description of the physical entities, the functions, and the user behaviors, the
boundaries and the boundary conditions can be included in the descriptions
of the system functions.
The second phase of the SysPMI is the recognition and characterization of
the top-level system functions in the simplest form and structure of subfunctions that is necessary to demonstrate the end-to-end system-level thread.
There can be multiple end-to-end system-level threads depending on the input
EMMI and the current actions of the system. The simplest case, the simplest
dataset, the simplest implementation, the simplest of physical structure,
computer hardware, computer software, and infrastructure and support
are the focus for demonstrating an end-to-end functionality. The few associated performance(s) are to be measured and set down as the benchmark
performance(s) that demonstrate feasibility. Various types of models may
be useful to establish a model of what an end-to-end system function might
entail. The SysPMI accommodates both the modeling aspects and the
benchmark execution as part of Phase II. Phase II spans the test planning,
test execution, and benchmarking of the single-most important systemlevel functional thread. The culmination of Phase I is the demonstration of