4 CONCLUSION
WebMathematica is a web version of Mathemat-
ica that uses a web server technology, HTML and
Java Servlet Pages. Calculations entered via web
pages are sent to kernel, where the result is cal-
culated and sent back to web pages. Several dif-
ferent functions programmed by us are gathered
into one Mathematica package called NLControl
for solving different modeling, analysis and synthe-
sis problems. At moment we have implemented
ﬁve functions from this package into webMathemat-
ica website. These functions are
Submersivity,
SequenceHk, Realization, Accessibility
and
Identifiability
. In the future we are expand-
ing our website with functions
Linearization
and
PrimeForm
. The function
Linearization
checks if
the state equations can be linearized via the static state
feedback and coordinate transformation, and ﬁnds
necessary transformations. The function
PrimeForm
transforms the system into the prime form, when-
ever possible, using the static state feedback, and
the coordinate transformations in the state and output
spaces. Besides continuous- and discrete-time sys-
tems we are also programming functions for systems,
described on homogeneous time scales (Bartosiewicz
et al., 2007).
ACKNOWLEDGEMENTS
This work was partially supported by the Estonia Sci-
ence Foundation Grant No 6922.
The authors thank M. Ondera for discussions on com-
parative evaluation of web-based symbolic tools pre-
sented in this paper and in (Ondera and Huba, 2005).
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