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10. Fundamental relations of traffic flow
This chapter discusses the fundamental relationships of traffic flow, focusing mainly on time mean speed and space mean speed. It elaborates on the definitions, derivations, and interrelationships between these parameters and introduces the fundamental diagrams of traffic flow, including flow-density and speed-density relationships. Also covered are the implications of these diagrams for traffic analysis and behavior.
Sections
This section explains the fundamental relations of traffic flow, focusing on time mean speed and space mean speed, and their interrelations.
Time mean speed is the average speed of vehicles passing a point over time.
Space mean speed considers the time taken for vehicles to cover a unit distance and is always less than or equal to time mean speed.
The fundamental diagram of traffic flow consists of speed-density, flow-density, and speed-flow relationships crucial for understanding traffic dynamics.
Time Mean Speed
The average of all vehicles' spot speeds measured over a certain duration.
Space Mean Speed
The average speed of vehicles over a unit length of road, accounting for the time each vehicle takes to traverse the distance.
Fundamental Diagram
Graphical representation depicting the relationships between traffic flow, speed, and density.
Flow-Density Relationship
Describes how traffic flow varies with vehicle density, showcasing maximum flow and jam density.
Speed-Density Relationship
Illustrates how speed varies with density, indicating maximum speeds at low densities and zero speeds at jam densities.
Practice Exercises
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting
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