  Recently an automaton property of quantitative nonblockingness was proposed
in supervisory control of untimed discrete-event systems (DES), which
quantifies the standard nonblocking property by capturing the practical
requirement that all tasks be completed within a bounded number of steps.
However, in practice tasks may be further required to be completed in specific
time. To meet this new requirement, in this paper we introduce the concept of
bounded-time nonblockingness, which extends the concept of quantitative
nonblockingness from untimed DES to timed DES. This property requires that each
task must be completed within a bounded time counted by the number of ticks,
rather than bounded number of transition steps in quantitative nonblockingness.
Accordingly, we formulate a new bounded-time nonblocking supervisory control
problem (BTNSCP) of timed DES, and characterize its solvability in terms of a
new concept of bounded-time language completability. Then we present an
approach to compute the maximally permissive solution to the new BTNSCP.
