Complex systems
Here we can introduce the concept of the complex system. Among
other aspects, the complexity of a system is determined by (Agrell,
1988):
The size of the system. Many involved personnel, measures and in
some cases organisations cause several, sometimes counter active,
processes to run simultaneously. The size aspect can relate to a geo-
graphic or a time aspect, i.e. a large area or a long time.
Interdisciplinary connection. The system is interdisciplinary,
i.e. the involvement of several branches of science are required to
address the problem. These may entail technology, social science
and humanism.
High order. There are many variables in the system. Conditional
variables describe the conditions in the system at any point in time.
The different parts of the system have different conditional variab-
les for describing the conditions in their particular parts.
Feedback loops. Information in various parts of the system is
forwarded to other parts. For example, knowledge gained on the
results of different working methods influences the choice of wor-
king method (in a certain situation).
Delay. There is a dynamic (i.e. time dependent) connection between
the quantities in a system and there is often a degree of sluggish-
ness in a certain measure and the effect that measure can have.
Non-linear relations. Nonlinear links exist between the quanti-
ties in the system. This means, among other things, that quanti-
ties are not always directly dependent on other quantities, which
results in the course of events in the system being in principle
impossible to predict.