| You
are here: Freetutes.com
> Systems
Analysis and Design
Analytical Representation of a System
As an abstraction we symbolically represent a system as a simple entity by using
a rectangular box as shown in Figure 1. In general, inputs such as stimuli and
cues are fed into a system that processes the inputs and produces an output. As
a construct, this symbolism is acceptable; however, the words need to more explicitly
identify WHAT the system performs. That is, the system must add value to the input
in producing an output.
We refer to the transformational processing that adds value to inputs and produces
an output as a capability. You will often hear people refer to this as the system’s
functionality; this is partially correct. Functionality only represents the ACTION
to be accomplished; not HOW WELL as characterized by performance. This text employs
capability as the operative term that encompasses both the functionality and performance
attributes of a system.
The simple diagram presented in Figure 1 represents a system. However, from
an analytical perspective, the diagram is missing critical information that relates
to how the system operates and performs within its operating environment. Therefore,
we expand the diagram
to identify these missing elements. The result is shown in Figure 2. The attributes
of the construct—which include desirable/undesirable inputs, stakeholders,
and desirable/undesirable outputs—serve as a key checklist to ensure that
all contributory factors are duly considered when specifying, designing, and developing
a system.
Figure 1 - Basic System Entity Construct
Figure 2 - Analytical System Entity Construct
<< Previous Page
| Contents | Next
Page >>
|
