![](bg5.png)
automaton refines to two displays with local
memories not only for the reason of robustness (they
can be compared) but also for functional
requirements (double-face stand). To guarantee the
overall fault detection capability of the device, it is
necessary also to consider checking the counter.
This task can be maintained by an I/O watchdog
application pattern that can compare input impulses
from the photoelectric pulse generator and the
changes of the total value; evidently, the appropriate
automaton provides again reversible counting.
5 CONCLUSIONS
This paper argues about the role of time in industrial
cyber-physical applications of information systems
using SCADA as a representative pattern. It restates
the essentials of the notion of time important not
only in general computer applications but also and
particularly in enterprise domain while focusing on
industrial supervision. Also, the manuscript brings
SCADA concepts and relates them to cyber-physical
system architectures. The case study demonstrates
some time-related techniques in frame of a simple
but real-world application.
This paper -- which was inspired originally by
the reports (Lee, 2007) and (Dietz, 2011) -- excerpts
and integrates some time-related ideas aiming at
CPS design domain. They were previously published
“per partes” in papers (Sveda and Vrba and Rysavy,
2007), (Sveda and Vrba, 2010), (Sveda and Vrba,
2011), (Rysavy and Sveda and Vrba, 2012) and
(Sveda and Vrba, 2013).
The references that wind up this manuscript
should be complemented by many more items
related to time modeling, namely those that were the
original source for the paradigm presented;
nevertheless they can be retrieved entirely from the
article (Sveda, 2013). Also, some technicalities
related to SCADA applications are dealt in more
detail by (Rysavy and Rab and Halfar and Sveda,
2012) and (Rysavy and Rab and Sveda, 2013).
ACKNOWLEDGEMENTS
This project has been carried out with a financial
support from the Czech Republic state budget by the
IT4Innovations Centre of Excellence, EU, CZ
1.05/1.1.00/02.0070 CEZ and by the MMT project
no. MSM0021630528: Security-Oriented Research
in Information Technology, by the Technological
Agency of the Czech Republic through the grant no.
TA01010632: SCADA system for control and
monitoring RT processes, and by the Brno
University of Technology, Faculty of Information
Technology through the specific research grant no.
FIT-S-11-1: Advanced Secured, Reliable and
Adaptive Information Technologies and through
research grant no. FIT-S-14-2299: Research and
application of advanced methods in ICT. The
authors acknowledge contributions to the presented
work by his colleagues Ondrej Rysavy, Petr
Matousek, Jaroslav Rab, Vladimir Vesely, Matej
Gregr and Libor Polcak from the Faculty of
Information Technology, the Brno University of
Technology.
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