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Viz Development Team

Dr Steven Halim
Dr Roland Yap Hock Chuan
Dr Lau Hoong Chuin
Felix Halim


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Latest Updates

30 May 2011: Viz v3 (the final one used in Steven's PhD thesis) is released. Click here to download it! No registration is needed

5 Sep 2008: See our results page to see what our 'state-of-the-art' LABS (Low Autocorrelation Binary Sequence) solver: TSv7 can do. These results will be presented in CP 2008.

Explain the basic ideas to me!What is COP?
What is SLS?
Was SLS behavior mysterious?

basic ideas!

On the left, Viz version 2 shows
Ro-TS-I versus Ro-TS-B on
QAP type B instances.

More details are in our results
documentations pages.

Download and try Viz Download Download and try Viz
and try Viz now!

It is free :), but you need to
register to obtain your key.

Overview: Now SLS behavior on COP Fitness Landscape is no longer too mysterious!

Viz (version history) is an off-line, user friendly, GUI-based, Stochastic Local Search (SLS) engineering suite.

Viz is used in Steven's 6-years PhD Thesis (2 Aug 2004-25 Aug 2010) (click here to view).

Viz can be used to visually analyze (white-box) Stochastic Local Search (SLS) (a.k.a. metaheuristic) algorithms while they are traversing the fitness landscapes of NP-hard Combinatorial Optimization Problems (COPs). This visualization is problem independent, which means that it can virtually be used to visually analyze almost any COPs that is attacked by an SLS algorithm. The visualization visualize both the fitness landscape (FL) of a COP instance and the search trajectory (ST) of a heuristic and stochastic SLS algorithm on that fitness landscape (the basic ideas behind this FLST visualization are explained here). Understanding search trajectory behavior of our SLS algorithm on the COP instances being attacked empowers the user (algorithm designer) to design better performing algorithm and focus the parameter space to a much smaller one. Once the SLS algorithm has been (carefully) designed and parameter space is (significantly) focused, Viz can then be instructed to perform full-factorial design (black-box) on the focused configuration space for even better performing algorithm.

We know that to engineer good performing SLS, one needs to design, implement, tune, analyze the SLS algorithm. The visualization in Viz is as a good tool for the design and analysis parts. The full-factorial design capability in Viz is a good tool for the tuning part. This combination is referred as the Integrated White+Black Box Approach.

Mirror page (which is outdated, this page is the more recent one):

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