Friday, December 5, 2008

On Continuous Monitoring and Continous Actions


In Israel, a new law has gone into effect in December 1st, to fight Spam - it forbids sending commercial material over Email, SMS and recorded phone calls, unless the person signed up explicitly (e.g. through a website); recorded phone calls are especially bad, picking up the phone and talking to recorded message is something I am allergic to... Unfortunately, this law is in effect only in Israel, and I keep getting Spam in Turkish and Russian -- I have already blocked more that dozen spamming sources, but others keep pooping.

Anyway -- this week, my Master student, Elad Margalit, had his final exam on the thesis, his thesis dealt in event-driven control of traffic lights, and he has shown (by simulation) that when the traffic lights frequencies of green and red in individual junctions are optimized based on the actual traffic it can shorten substantially the waiting times (there may be various goal functions here). This is done by continuous monitoring of the traffic (entrance and exit from a road segment by camera). IBM Research has done a lot of work in the area of "continuous optimization" that deals with solving optimization problem continuously, there are two variations: Solve the optimization problem all the time (in our case - for each cycle of the traffic light), or monitor all the time and solve the optimization problem only when there is a significant change from the base assumptions (in our case -- when the distribution of traffic in the various direction is significantly different, otherwise leave the traffic lights policies as is), this is based on the assumption that the cost of monitoring is much lower than the cost of actual changing the system behavior; if no such difference then we can use the continuous actions.

It is interesting to note that Coral8 added in its logo the trademarked expression "Continuous Intelligence". Interesting phrase, not sure if there is indeed intelligence, but I guess that intelligence is in the eyes of beholder.