Similar to the PrT origin and destination demand, the PuT origin and destination demand can also be distributed to PuT connectors either arbitrarily or by percentage (Distribution of demand of a zone to the connectors). Contrary to PrT, PuT does not provide two variants for the proportional distribution but always uses the model "Each single OD pair (MPA)". For PuT, the distribution by percentage may be used, for example, to assign the transport demand to all stops which are located within a community (modeled as one zone).
The proportional distribution of the PuT is effected similar to the distribution by percentage of PrT. All origin and destination demand of the zone is distributed onto all connectors of the zone proportionally to their respective current connector weights. During the assignment, a temporary virtual zone is generated for each connected node. The virtual zone's total demand complies with the connector's original share in the total demand of the original zone. The assignment calculation is based on the virtual zones. After the assignment, the temporary zones are deleted and the results are allocated to the original zones.
Example
Two zones with the following connectors are given.
- Zone 100 with distribution by percentage, connected nodes 1, 2 and 3
- Zone 200 with distribution by percentage, connected nodes 4 and 5
The connector weights for origin and destination are set according to Table 174.
|
Connector node |
Weight (origin) |
Weight (destination) |
|
1 |
20 |
0 |
|
2 |
30 |
80 |
|
3 |
50 |
20 |
|
4 |
40 |
90 |
|
5 |
60 |
10 |
- Transport demand from zone 100 to zone 200 = 1000 trips
- Transport demand from zone 200 to zone 100 = 500 trips
For the assignment, this leads to the temporary demand matrix displayed in Table 175.
|
Virtual zone |
1 |
2 |
3 |
4 |
5 |
|
1 |
- |
- |
- |
180 |
20 |
|
2 |
- |
- |
- |
270 |
30 |
|
3 |
- |
- |
- |
450 |
50 |
|
4 |
0 |
160 |
40 |
- |
- |
|
5 |
0 |
240 |
60 |
- |
- |
The value of the temporary OD pair 1 ⇒ 4 is calculated from 1,000 • 0.2 • 0.9 = 180.
