CE 572 - Intersection Traffic Operations
Spring 2007

28 December 2006
What to include in each class?  Is there a structure that I can follow that will take advantage of the 75 minutes of class time?  It should include several things: (1) discussion of previous assignment, (2) lecture and discussion, and (3) new assignment).

1 January 2007
Note from Tom Urbanik:
I think there is a good paper after we get the option zone nailed down. Let me explain my view. First, the advance detector has typically been located at the safe stopping distance. This is analytically derived point. Alternatively, one could argue the empirical point where 90 percent of the drivers stop (a behavioral point). This is the 5 second +/- point. It might be good to set up a table for comparison. I believe 5 seconds is more conservative. Either way this is the “can stop comfortably, and safely” point. The downstream point is a driver behavior point (empirical derived) and is the point where 90 percent of the drivers won’t stop. I do not know of an analytical equivalent (remember, this is not a yellow or red clear issue which relates to the can stop comfortably point). This point is about 2 seconds from the intersection, 1 second after you realize that the light has turned yellow. One could create an analytical and conservative point by saying the won’t stop point is 1 second from the intersection. If you are 1 second from the intersection, you clearly can stop, because it will take 1 second for PIEV, so you are at the stop line when you decide. In either case, I have the yellow BEFORE the stop bar. It is both SAFE and EFFICIENT. Also keep in mind the 2 second and 5 second point are based on limited data and do vary. Also remember we are trying to make it better, not perfect. We are also trying to make it reasonably efficient, BECAUSE IF IT IS NOT EFFICENCT, YOU INCREASE MAX OUT. So, the option zone is the space between “can’t stop comfortably” and “won’t stop” (to close to stop).

27 February 2007
Some thoughts on class 12 today.  We've just completed a section of Bonneson and McCoy traffic detector handbook.  Good material and had the students read and write about what they learned.  What would be good is to take this material and develop a set of problems (calculations) or present them with a set of situations that they had to deal with that required using the material from that chapter.  That might be the focus for next Tuesday's class.