Is self-expression useful? Evaluation by a case study

In the context of adaptive component-based systems,
self-expression is the capability of changing the adaptation
pattern when some changes occur in the system itself or
in its environment. Even if functional requirements can be met
without changing the adaptation pattern, the achievement of
non-functional requirements, such as performance, can benefit
from a change of adaptation pattern.
The aim of this paper is to show, by means of a case study in
swarm robotics, that a change of adaptation pattern can affect
the performance of a system. In our case study, the robots
must collect food items (foraging); we will show that while
in an open arena the Reactive Stigmergy Pattern performs
better, the Centralised AM Pattern better suits the presence of
obstacles.
Since the situation of the environment can be unknown in
advance, or it can change at runtime, we claim that the change
of adaptation pattern can be useful in adaptive componentbased
systems.