Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coarse abstractions make Zeno behaviours difficult to detect   An infinite run of a timed automaton is Zeno if it spans only a finite amount
of time. Such runs are considered unfeasible and hence it is important to
detect them, or dually, find runs that are non-Zeno. Over the years important
improvements have been obtained in checking reachability properties for timed
automata. We show that some of these very efficient optimizations make testing
for Zeno runs costly. In particular we show NP-completeness for the
LU-extrapolation of Behrmann et al. We analyze the source of this complexity in
detail and give general conditions on extrapolation operators that guarantee a
(low) polynomial complexity of Zenoness checking. We propose a slight weakening
of the LU-extrapolation that satisfies these conditions.

7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con