Bethel ME Overweight
FHWA Type 10 Westbound 2001
The JOHO image above is an example of the use of American
Image Inc.'s innovative visualization technique. Using JOHO,
you can make displays from your large traffic information bases. You can quickly
discern patterns and exceptions to the patterns, even in the large data sets
produced with vehicle sensors.
This image shows the total number of overweight (exceeding 100,000 lbs)
westbound FHWA Type 10 (6-axle) trailer trucks passing the WIM sensor in Bethel,
Maine for every hour in 2001. The image contains 8,760 data points. This is far
more information than traditional graphics programs can display.
Image Layout
The image has twelve panels, each showing one month in 2001, starting in the
upper left and ending in the lower right. As labeled on December’s panel, the
24 cells in the top row of a panel represent the hours in the first day of the
month. The bottom row of cells represents the last day of the month. The time
through each day is measured horizontally along each row, from the hour
beginning at midnight on the left to the hour beginning at 11 PM on the right.
Noon is halfway across the panel.
Each colored cell indicates the total number of overweight westbound Type 10
trucks passing the sensor at that day during that hour. The legend at the right
indicates the relation between color and number of vehicles. We have kept the
same color scale we used in the eastbound image because the directional
difference in the counts of overloaded trucks is then immediately apparent.
Image Interpretation
The most obvious pattern for these overloaded trucks is that there are
relatively few overloaded westbound trucks, perhaps a peak of 4 or 5 trucks per
hour. Even with the “all blue” color scale, some variation with season is
visible. The busiest times are January, February, and March. This is very
different from the summertime peaks in the eastbound traffic. The
equivalent images (not on the web site) that show all of the Type 10 trucks do
not show a directional difference.
More Traffic Information
This westbound overloaded Type 10 traffic pattern is quite different from the
eastbound pattern. Detecting
such patterns and directional differences would take hours of analysis using the
sensor vendor’s reporting software and traditional graphics programs. JOHO
makes them visible immediately with no additional labor after automated image
generation.
This site also contains FHWA Type 11 images and
total vehicle
count images that show other examples of how the Maine DOT is using JOHO
to monitor their sensors and to understand traffic patterns throughout the
state.
