Understand the complexity of urban transport problem, using the Causal Loop Diagram technique
1. Understand the complexity of urban transport
problem, using the Causal Loop Diagram technique
Peraphan Jittrapirom, M. Eng., PhD. Candidate
Technical University of Vienna
peeratop@gmail.com
www.kamanakom.wordpress.com
3. System thinking Causal Loop
Diagram (CLD)
Urban Transport
Problems
Application of
CLD in urban
transport
problems
4. • A way to understand how a set of related entities function
by understand their connectivity
• Contrast to the reductionist approach
• Understand root cause of problem, no just symptom
System thinking
5.
6.
7. • Entity
• Dangle (input and output)
• Positive and negative arrows
• Arrow with time lag
Entity Dangle
+ -
Causal Loop
Diagram (CLD)
8. CLD warnings
• Must be CAUSAL not
correlation
• Plus arrow indicates
two entities are
moving in the same
direction
• Minus arrows indicates
two entities moving in
opposite direction
13. • Using CLD to illustrate the casual links between transport
entities, their causes, and their effects.
Application of
CLD in urban
transport
problems
21. Tests real policy with the CLD
• Seven measures were extracted from 19 Chiang mai's Land transport
sub-committees:
①Promotion of non-personal vehicle modes
②Road capacity expansion
③Road capacity reduction
④Relocation of traffic attractors and expansion of the city area
⑤Land use planning
⑥Population controls
⑦Improve transport organisation
Application of
CLD in urban
transport
problems
23. Summary of measures assessed
• Two mitigations proposed have
direct effects on alleviating
transport problems;
• Two have directs effects on
aggravate the problems;
• Two with direct effects but their
impacts depends on the detail of
the polity; and
• One with indirect effects.
• Decision makers have slightly less
than 30% chance of solving the
transport problems using
mitigations that they believe will
alleviate the problem.
Types of mitigation
proposed
Effects
1. Promotion of non-
personal vehicles mode
Alleviate transport
problem
2. Road capacity
expansion
Aggravate transport
problem
3. Road capacity reduction Alleviate transport
problem
4. Relocation of traffic
attractors and expansion
of city
Aggravate transport
problem
5. Land use planning Impacts depending on
measures
6. Population control Indirect effects.
7. Improve transport
organization
Impacts depending on
measures
24. Conclusion
• Problem understanding increases the chance to solve it
• System thinking and CLD are tools to help better
problems understanding and to solve them
• Can be used with partial differential equations or other
mathematical models to provide quantitative analysis