(0 + 0) = 1. This leads to a new price-of-anarchy of
3+1
1
= 4, which is worse. The costs of this transfor-
mation would be the same.
Although anticipated and illustrated by a straight-
forward example, these results demonstrate the abil-
ity to forecast the costs and benefits of structural
changes in complex organizations through the quan-
titative modeling and simulation of distributed agents
using a formal digital-twin approach.
6 CONCLUSION
Our research explores self-modifying systems within
the context of Org-MAS and MAPE-Loop. We use
the formalism HORNETS for the twin model to predict
the cost-benefit ratio of adaptation. Since the model
includes stochastic elements, we require an appropri-
ate analysis tool. In this study, we examine a simple
case study using the battle of sexes game to demon-
strate that the quantitative analysis of adaption using
HORNETS is feasible and beneficial for the designer.
In our current research, we are focusing on
converting elementary, two-levels, HORNETS into
stochastic Symmetric Petri Nets (SSN) (that can be
assessed within the GREATSPN framework (Am-
parore et al., 2016)) by mimicking net-tokens through
an emulator (Camilli and Capra, 2021). Given the
lower level of abstraction in SSN, we also aim to de-
scribe the semantics of HORNETS employing an ad-
vanced algebraic framework, such as Maude (Clavel
et al., 2007). This extends the approach we ap-
plied to Elementary Object Systems (EOS) (Capra
and K
¨
ohler-Bußmeier, 2023b; Capra and K
¨
ohler-
Bußmeier, 2023a).
In general, such a translation is quite complex due
to the nested nature of Nets-within-Nets. (Note, that
in general there is no equivalent unnested nets, since
the reachability problem is undecidable for Nets-
within-Nets (K
¨
ohler-Bußmeier, 2014b), while it is de-
cidable for place transition nets; so we need at least
colored tokens and algebraic inscriptions.) However,
we observed that our SONAR-MAPE-Loop has an in-
teresting structural property, that is, the system-net
does not combine or distribute net-tokens of the same
net type, i.e., we have no forks or joins, which are usu-
ally the source of complexity for HORNETS (K
¨
ohler-
Bußmeier, 2017).
For a similar subclass of EOS, called General-
ized State Machines (GSM), we have already shown
in (K
¨
ohler-Bußmeier, 2014b) that this structural sub-
class can be translated into an equivalent unnested
Petri net. In ongoing work, we extend this idea to ob-
tain an equivalent unnested algebraic Petri net from a
fork/join-free EHORNET. This translation would al-
low symbolic methods to rely on established and effi-
cient analysis methods.
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