The crash rate on a heavily-traveled two-lane rural highway is abnormally high. The corridor is 14 miles long with an ADT of 34,000. An investigation has determined that head-on collisions are most common, with an RMVMT of 4.5, and are caused by vehicles attempting to pass. Determine an appropriate countermeasure and calculate the estimated yearly reduction in total crashes.
What will be an ideal response?
Selected countermeasure – Add passing lanes
Crash modification factor = 0.65 (Highway Safety Manual recommendation)
RMVMT = A(100,000,000) / (ADT)(365 days)(length of road section)
4.5 = A(100,000,000) / (34,000)(365)(14)
A = 7.82 => 8 crashes per year
(8 crashes/year)(0.65) = 5.2 crashes per year after countermeasure
Reduction in crashes = 8 – 5.2 = 2.8 crashes/yr
Therefore, the estimated reduction in crashes is approximately 3 crashes per year.
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Figure 24-1
The accompanying diagram uses ____________________ to shunt the resistors out of the circuit after some period of time.
Fill in the blank(s) with the appropriate word(s).
Why is the cooling temperature difference often different from the difference between the indoor and outdoor temperatures?
A) The cooling temperature difference takes heat storage and daily temperature range into account. B) ACCA weather data is more accurate than the National Weather Bureau. C) The cooling temperature difference takes latent heat gain into account. D) Air-conditioning equipment manufacturers use their own temperature scale established by AHRI, which is different from either Fahrenheit or Celsius.
Brake drums (or discs) must not have cracks longer than _____ the width of the friction area.
a. 1/10 b. 1/2 c. 1/3
The term used to describe the programming of a drive so that it avoids running within a harmful speed range is __________.
A. speed compensation B. critical frequency rejection C. skip frequency D. both b and c