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I N V I T A T I O N<br>
<div class="moz-forward-container"><font face="sans-serif"> <br>
<br>
<br>
to the Research Seminar 'Computer Graphics, Image Processing,
and Visualization'<br>
<br>
on Tuesday, May 13th, 2015, at 1:15 PM,<br>
in Room P-701 in the Paulinum, Augustusplatz.<br>
</font><br>
<br>
<br>
The first talk is given by<br>
<br>
Sebastian Volke<br>
Image and Signal Processing Group<br>
Institute of Computer Science<br>
Leipzig University<br>
<br>
and is entitled<br>
<br>
"Visualizing Topological Properties of the Search Landscape of
Combinatorial Optimization Problems"<br>
<br>
Abstract:<br>
<br>
Discrete combinatorial optimization problems such as the
Traveling Salesman<br>
Problem have various applications in science and in everyday
life. The<br>
complexity of the problem and the effectiveness of search
algorithms depend not<br>
only on the problem itself but also on the search operator in
use. Therefore,<br>
investigating search operators and the search landscapes they
give rise to is<br>
an important field of research. However, a full topological
analysis of the<br>
landscapes is impossible due to their exponentially growing
size.<br>
<br>
We propose an analysis method and a visualization system that
gives a visual<br>
intuition about topological properties of the search
landscape. We obtain<br>
representative samples of the search landscape and its optima
by random<br>
sampling and by computing the related optima using local
search. The<br>
distribution and the correlation of this data within the
search landscape is<br>
visualized with a combination of one and two dimensional
visualizations. Using<br>
the TSP as an example we illustrate how the visualization
supports the<br>
understanding and comparison of search landscapes and their
complexity.<br>
<font face="sans-serif"><br>
<br>
<br>
The second talk is given by<br>
<br>
Stefan Koch<br>
Image and Signal Processing Group<br>
Institute of Computer Science<br>
Leipzig University<br>
<br>
and is entitled<br>
<br>
</font><font face="sans-serif">"Comparing Finite-Time
Lyapunov Exponents in Approximated Vector Field"<br>
<br>
Abstract:<br>
</font><br>
<font face="sans-serif"> In the context of fluid mechanics,
larger and larger flow fields arise. The<br>
analysis of such fields on current work stations is heavily
restricted by<br>
memory. Approximation limits this problem.<br>
<br>
In this paper, we discuss the impact of vector field
approximation on<br>
visualization techniques on the example of Finite-Time
Lyapunov Exponent (FTLE)<br>
computations. Thereby, we consider the results of three
different vector field<br>
compression approaches and analyze the reliability of
integration results as<br>
well as their impact on two different FTLE variants.<br>
<br>
<br>
<br>
<br>
On behalf of Professor Scheuermann all those interested are
cordially invited to attend.<br>
<br>
<br>
Yours sincerely,</font><br>
<br>
Tom Liebmann<br>
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