Use this procedure to calculate the spatial distribution of orders by demand stratum.
1. On the toolbar, click the 
Open 'Procedure sequence' window button.
The Procedure sequence window opens.
2. To the procedure sequence, at the position of your choice, add the Tour-based freight generation and distribution procedure of the Demand model category (Setting up and starting the procedure sequence).
3. In the row of the inserted procedure, click the button in the Reference object(s) column.
The Demand strata selection window opens.
4. In the Select demand model list, click the demand model the demand strata belong to.
5. In the Demand strata selection list, select the demand strata you would like to calculate the production and distribution for.
6. Confirm with OK.
The demand strata selected are listed in the Reference object(s) column.
7. Make sure the added procedure is highlighted. Then, in the Operations section, click the Edit button.
The Parameters generation and distribution window opens.
8. Make the desired changes in the Production tab.
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Element |
Description |
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Calculate attributes for active zones only |
If this option has been selected, the distribution and production is calculated only for active zones (Using filters to set network objects active or passive and Setting network objects active/passive via the spatial selection). |
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Set the attributes of passive zones to 0 |
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Matrix balancing for active zones only |
Select this option to consider active zones only for scaling of sums. |
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Sum up values |
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Calculate production only in the first line block |
If the option has been selected, the production is calculated only in the first run and remains constant if during the procedure, the distribution is calculated again. |
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Demand stratum |
Display all demand strata Note For each demand stratum, separate settings can be made. |
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Matrix balancing |
If the production and attraction sums differ, use the drop-down list to specify the sum (productions, attractions) you want to base the production on. |
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Production definition |
Formula for orders generated for each origin zone as a zone attributes formula (Calculating trip generation) |
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Attraction from destination structure |
Here you can select for which demand strata the attraction should be calculated. |
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Attraction definition |
Formula for the received orders for each destination zone as a formula on the zone attributes (Calculating trip generation) |
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Apply to all DStrata |
Click this button to adopt the current settings for matrix balancing and production and attraction rates in all demand strata. |
Select this option to set the attribute values of passive zones to zero.
If the option is not activated, the attribute values of the passive zones remain unchanged.9. Make the desired changes in the Attraction from destination structure tab.
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Element |
Description |
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Demand stratum |
Display of all the demand strata for which the Attraction from destination structure option in the Production tab is selected. |
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Target segment |
Display of all target sectors for which the attraction is calculated |
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Target potential |
Formula for the target potential at the destination zone for each target sector and demand stratum |
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Weight |
Weight for the calculation of the shares of the target sector in the total demand of the demand stratum |
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Share |
Share of the target sector in the total demand of the demand stratum |
10. Make the desired changes in the Distribution tab.
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Element |
Description |
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For active OD pairs only |
If this option has been selected, only those OD pairs which are in the active state are considered (Exception: Filter for OD pairs). |
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Exclude OD pairs connecting passive zones |
If this option has been selected, only OD pairs between active zones are considered (Using filters to set network objects active or passive and Setting network objects active/passive via the spatial selection). |
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Set any result demand matrix to 0 prior to calculation |
If this option has been selected, all demand matrices allocated to the demand strata are set to 0 prior to summing up the calculated OD demand. Note You should check this option if distribution is to be calculated for all demand strata allocated to the same demand matrix. |
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Utility definition |
Defines the attractiveness for an origin zone of a destination zone to be chosen as an order objective. Via this button, you may - in a separate window - define a combination of matrices and attribute vectors which will be used as utility matrix for the particular demand stratum during Trip distribution. |
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Function type |
Use the drop-down list to select the type of utility function you want to use for the calculation of the distribution. |
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a, b, c |
Estimated parameter values for the utility function modeling the response of travelers to distance or time conditions. The parameters can take negative values. Depending on the selected function, parameters that are irrelevant for the respective function are grayed out. |
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Direction parameters |
Use this option to select the distribution model to be calculated. Constrained production If this option has been selected, trip distribution is calculated singly-constrained for production. The Production zone attribute is taken into account for each zone. Constrained attraction If this option has been selected, trip distribution is calculated singly-constrained for attraction. The Attraction zone attribute is taken into account for each zone. |
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Distribution matrix |
Reference to the demand matrix to which the trip distribution result is saved for the selected demand stratum (Properties and options of demand strata). |
11. Confirm with OK.
12. Execute the procedure (Executing procedures in the procedure sequence).
The production and distribution is calculated. The calculation results are saved in each demand matrix for each demand stratum.
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Note: You can show and edit the demand matrices (Managing, showing and analyzing matrices). |
