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I have a PN for an elevator and I'm using timed PN so that I can find out if the elevator can get to a certain point within certain period of time!

is that correct ?

I can make sure of the time condition , but doesn't time PN have algorithms to do so ?

any reference you recommend about this issue is highly appreciated :)
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I'm sorry to say I know only the algorithm for non-timed 1-concervative Petri Net. This algorithm is based on linear algebra and all it can do is to determine reachability of any location from any other location. For example, if you identify one or more locations as a deadlock but can proof that none of the deadlock locations is reachable from a starting location, this serves as a proof that the whole system is deadlock-free. To proof that, you formalize the Petri Net into linear equations which you can solve automatically using the regular algorithm from linear algebra and/or computer-algebra system (CAS), which is not too hard to create ad-hoc, just for this case.

See:
http://en.wikipedia.org/wiki/Petri_net[^].

This is the article explaining linear algebra formalism in a informal manner, with examples: http://msdn.microsoft.com/en-us/library/ms810303.aspx[^].

Now, few words about timed Petri Nets. Even though I'm not well familiar with them, I can tell you for sure that they wan't predict guaranteed times of execution unless your system is a hard real-time one. (See http://en.wikipedia.org/wiki/Real-time_operating_system[^], http://en.wikipedia.org/wiki/Hard_real_time#Hard.2C_firm.2C_and_soft_real-time[^].) The problem is: the real-life multithreading but not hard real-time (:-)) system will introduce nondeterministic time delay for any predicted execution times.

See:
http://www.google.com/url?sa=t&rct=j&q=%27timer+petri+net%27&source=web&cd=3&ved=0CDYQFjAC&url=http%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fdownload%3Fdoi%3D10.1.1.69.5289%26rep%3Drep1%26type%3Dpdf&ei=bA_xTvjNOM3pggf8_sWzAg&usg=AFQjCNEnwxcAa-mKTBEV7-RGUsjMgdEZUw[^],
http://www.lsv.ens-cachan.fr/Projects/anr-dots/PUBLIS/RS-concur09.pdf[^],
http://www.lsv.ens-cachan.fr/Publis/PAPERS/PDF/DADSS-tacas07.pdf[^].

Try to find some more, but this is not a very popular field of science and technology, not very easy to find what you want.

—SA
 
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