In Visum multiple line blocking results can be stored in parallel. These are stored in so-called block versions. In this way, alternative plans with different parameter settings can be compared easily to one another. For example, a block version where interlining is allowed and another one where this is not allowed, can be maintained in the model. Procedures such as the calculation of PuT operating indicators always refer to the current active block version.
Important parameters of the Line blocking procedure are attributes of a block version, so that the parameter settings are still known afterwards, and especially the check line block can use them for comparisons with the same parameters after changes. The block version attributes are described in Table 207.
|
Attribute |
Description |
|
Start day index |
First day of the line blocking time period. The line blocking time period has to lie inside of the calendar period. |
|
End day index |
Last day of the line blocking time period. |
|
Valid from |
Date of the start day if a calendar is used. |
|
Valid to |
Date of the end day if a calendar is used. |
|
Interlining permissible |
Specifies, whether the line blocking and check line block procedures should create empty trips (Line block check). |
|
System routes usage |
Specifies, whether system routes should be used for generating empty trips. |
|
Only use active system routes |
Specifies, whether only active system routes or all system routes should be used to create empty trips. |
|
Regard preparation times |
Specifies, whether pre- and post-preparation times should be considered for line blocking and check line block. |
|
Short turn permitted |
Specifies, whether short turns should be permitted for line blocking and check line block. This means that the layover time is allowed to differ from the pre- and post-preparation times. The short turn properties are set in the attributes for the maximum dwell time, the reduced pre-preparation time and the reduced post-preparation time. |
|
Attribute for maximum dwell time |
Specifies the stop point attribute, where the values of the maximum dwell time is contained. |
|
Attribute for pre short turn |
Specifies the vehicle journey section attribute, where the values of the reduced pre-preparation time is contained. |
|
Attribute for post short turn |
Specifies the vehicle journey section attribute, where the values of the reduced post-preparation time is contained. |
|
Link attribute for shortest path |
Specifies the link attribute, which is used as a criterion for the shortest path search for empty trips. |
|
Total vehicle demand |
Number of required instances of vehicle combinations for all blocks of the block version |
|
Vehicle demand (per vehicle combination) |
Number of required instances of a certain vehicle combination for all blocks of the block version |
|
Required vehicles for standard vehicle combination |
Number of required instances of the vehicle combination "no vehicle combination". If no vehicle combination is specified at the vehicle journey section, this specification is evaluated as an own vehicle combination, whose required vehicle is accounted for by this attribute. |
|
Vehicle unit requirement (per vehicle unit) |
Number of required instances of a certain vehicle unit for all blocks of the block version |
|
Required user-defined block item types |
Set of user-defined block items ('activities') that must be scheduled in blocks of this block version, depending on time and distance |
