Xiao Liu PhD Thesis.pdf - Faculty of Information and Communication ...

90% or 80% makes much more sense. Second, it is better to model activity duration
as random variables instead of static time attributes in system environments with
highly dynamic performance to facilitate statistical analysis. Third, to facilitate the
setting of fine-grained temporal constraints at build time, continuous states based
temporal consistency model where any fine-grained temporal consistency state is
represented by a unique probability value is required rather than discrete multiple
states based temporal consistency model where temporal consistency states are
represented by coarse-grained qualitative expressions.
5.3 Setting Temporal Constraints
In this section, we present our negotiation based probabilistic strategy for setting
temporal constraints at build time. The strategy aims to effectively produce a set of
coarse-grained and fine-grained temporal constraints which are well balanced
between user requirements and system performance.
Table 5.2 Probabilistic Setting Strategy
As depicted in Table 5.2, the strategy requires the input of process model and
system logs. It consists of three steps, i.e. calculating weighted joint distribution,
setting coarse-grained temporal constraints and setting fine-grained temporal
constraints. We illustrate them accordingly in the following sub-sections.
80