Traffic wave
Presentor : Hsu, Hung-Wei
What is traffic wave?

Why is it important?


How does it appear?
- Traffic Light
- Cycle Effect
- Lane Reduction
Important Factors
- Reaction time
- Variance between drivers
- Density of cars
Model building
- Safety distance d(v)
- Constant acceleration
- Variance of acceleration
Safety Distance
d_{safe}(v) \approx v + \frac{1}{2}a\frac{v^2}{a^2}
=v+\frac{v^2}{2a}
dsafe(v)≈v+21aa2v2=v+2av2
d_{acc}(v) \approx v + \frac{1}{2}a\frac{(a+v)^2}{a^2}
=v+\frac{(a+v)^2}{2a}
dacc(v)≈v+21aa2(a+v)2=v+2a(a+v)2
Traffic Light

Reaction time = 1


Reaction time = 10


Reaction = 20


Speed - Reaction time

Cycle effect

Cycle effect


reaction time = 20
reaction time = 50
Reaction time
Cycle effect



a \sim gaussian(\mu, \sigma)
a∼gaussian(μ,σ)
\sigma = 0
σ=0
\sigma = 0.1\mu
σ=0.1μ
\sigma = 0.2\mu
σ=0.2μ
Density Effect


Threshold appears
Comparison



Reaction
Variance of acceleration
Density
Lane Reduction


Low density
High density


Lane Reduction




Lane Reduction

Notice distance
Summary
- Keep alert - reaction time
- Don't be a strange driver
- Don't drive during rush hour
final
By 許泓崴
final
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