Civil Engineering ETDs


John V. Wait

Publication Date



This study outlines a method whereby a small, specialized "on-line" digital computer could be used to control urban vehicle traffic at a signalized intersection. In the basic system proposed, the computer uses as input data a "history" of the instantaneous vehicle flow, in terms of number of cars arriving and arrival time. The data are stored for a period of 240 seconds in a magnetic drum memory. Once each 1/2 second, the computer examines the arrival pattern of cars and compares the delay being imposed on the waiting cars versus the delay which would be imposed on the cars on the moving phase if the lights were changed for a sufficient time to clear the waiting queue. The computer then decides when to change the signal lights and what the timing interval for the next phase should be.

Document Type




Degree Name

Civil Engineering

Level of Degree


Department Name

Civil Engineering

First Committee Member (Chair)

Richard Kerr Moore

Second Committee Member

Arnold Herman Koschmann

Third Committee Member

Arthur Wilson Melloh