Fundamentals of Transportation/Queueing and Traffic Flow/Additional Problems

1. Why were ideal models of flow vs. density assumed for so long if data did not support it?
2. How do we estimate density of road (in planning or as an after-evaluation?)
3. Explain why the graph of density vs. speed at a bottleneck is not linear using queueing theory.
4. Define time headway and space headway.
5. Why do we need two different speed measures, define each, which is more appropriate? How are these measures related?
6. What are the 3 fundamental principles of traffic flow? What are their relationships?
7. What does the slope on the space time diagram tell you?
8. What is the difference between looking at traffic as a particle rather than a flow?
9. Define density.
10. As density increases, what happens to flow?
11. Where are time-space diagrams used?
12. What is space headway on a space-time diagram? What is time headway?
13. What does high density mean?
14. Draw a realistic speed vs. density graph? Compare it with the traditional model.
15. Describe headway speed?
16. How does a bottleneck affect traffic flow upstream of the point?
17. What might cause a falloff of flow as density rises?
18. Why does density reach a maximum when flow is zero?
19. How do these analysis of mathematical relationships between q,k,v help in planning, design, and operations of road?