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Integration in Systems Engineering Context
limitation of the bricks and mortar. Supplying water to the house includes
the systems of source, storage, and distribution. The problem domain for the
abstraction shelter includes all problems associated with each of the systems
that interact with the house. Problems with the source (e.g., insufficient rain
and runoff) have an impact on house and living in the environment of the
house. So the abstract problem of shelter subsumes many other problems
due to location, circumstance, specific design details, and habits of the
inhabitants. Nested problems intertwine like a cauldron of cooked and
drained spaghetti. Parsing the topology of nestedness can be taken in many
dimensions. Nested problems have different relations depending on the
relations between the dimensions in which the problem is expressed.
Figure 5.1 relates problem A (the abstraction of house) to the reservoir that
stores water (Problem A 4 ) to the distribution of water from municipal storage
to the house (Problem A 1 ) to piping the water to the rooms in which water is
desired (Problem A 2 ) to the restricted use by the inhabitants (Problem A 3 ).
In this example, the connection of the municipal water pipe to the house is
indicated as (Problem A 5 ), while the source of water (rain) is disconnect
(Problem A 6 ).
Hierarchical Problems
Problems of a hierarchical nature are related by the need to associate one
problem with another in a structure of subsets. Each problem is considered
to be a subset of another problem, with the highest level in the hierarchy
representing the totality of the subset problems. All the problems in the hierarchy are related by a common factor that weaves a common theme throughout
their relations. Such a hierarchical structure of problems provides a convenient
Problem A
abstraction
Problem
A 1
Problem
A 2
Problem
A 3
Problem
A 4
Problem
A 5
Problem
A 6
FIgure 5.1
Nested problems related through abstraction.