Highway Design
Crouse Hinds PCE-3000 Traffic Controller- Dials And Cams – YouTube.
Albany has a lot of the circa-1950 Crounse-Hinds of Syracuse Traffic Signals and controllers. Quite reliable, they don't always work properly in cold weather.
The controllers (shown in this video) are prone to malfunctioning in cold weather due to the grease binding up and causing 5 minute yellow lights and 20 minute red lights.
Here is some of the old traffic signals, as shown on Youtube: https://www.youtube.com/watch?v=jryVhVsYV_s
1940 Tacoma Bridge.
Today is National Stress Awareness Day.
One stress that effects nearly every part of our world is harmonic resonance, which can have disastrous results on infrastructure and other manufactured products if engineers don't fully account for it.
Learn more about fundamental and harmonic frequencies:
http://hyperphysics.phy-astr.gsu.edu/hbase/waves/funhar.html