Block item and block item type
Each block is made up of individual sections, which are called block items. Each block item has a start and an end, and a start stop and an end stop. The Table 220 shows the attributes of a block item and their meanings.
Attribute |
Description |
Blocking day |
Specifies, to which blocking day the block item has been assigned. |
Block item type number / name |
Number and name of the block item type of the block item. By default, the four block item types vehicle journey, empty trip, layover time and depot are defined. |
Line name |
Line that is used by this block item. The attribute only displays a value if the block item is a vehicle journey. |
Line route name |
Line route that is used by this block item. The attribute only displays a value if the block item is a vehicle journey. |
Direction code |
Direction of the line route that is traversed by this block item. The attribute only displays a value if the block item is a vehicle journey. |
Time profile name |
Time profile that is used by this block item. The attribute only displays a value if the block item is a vehicle journey. |
Vehicle journey number |
Vehicle journey that is used by this block item. The attribute only displays a value if the block item is a vehicle journey. |
Vehicle journey section number |
Vehicle journey section that is traversed by this block item. The attribute only displays a value if the block item is a vehicle journey. |
Relative start day index |
Index of the calendar day on which the block item starts, based on the line blocking period. |
Absolute start day index |
Index of the calendar day on which the block item starts, based on the calendar. |
Absolute start day time |
Number of seconds from the start of the calendar to the start time of the block item. |
Start time |
Start of the block item |
Relative end day index |
End day index of the block referring to the line blocking time interval of the block version. For closed blocks, the value is always equal to the number of days in the line blocking time interval. |
End time |
End of the block item |
From stop point number / name |
Stop point where the block item starts. Matches To-stop point if it is a block item of type layover or layover time. |
To stop point number / name |
Stop point where the block item ends. Matches From-stop point if it is a block item of type layover or layover time. |
Duration |
Time period of the block item. For block items with a user-defined block item type (for example maintenance) this duration can be edited manually. |
Length |
Distance of the block item. For block items with a user-defined block item type and block items of type empty trip, you can edit the length manually. |
Is in depot |
Indicates a downtime (item of type layover) as taking place in depot. Has no effect for other block items. |
Length until next occurrence |
Distance until a block item of the same type appears in this block again. Only available for block items of a user-defined block item type. |
Time until next occurrence |
Period until a block item of the same type appears in this block again. Only available for block items of a user-defined block item type. |
Departure minute |
Only the minute value of the attribute start time is displayed (for example, start time: 07:20:00, departure minute: 20). |
Arrival minute |
Only the minute value of the attribute end time is displayed (for example, end time: 07:20:00, arrival minute: 20). |
Chain number |
Number of the chain. A chain represents a complete run through the block, throughout the entire line blocking time interval. There are as many chains as blocking days, and the N-th chain starts on the first day of the line blocking time interval on blocking day N. |
Starts in forward direction |
Specifies whether the activity starts in forward direction or in reverse direction. The attribute is set during the line block check if the running direction of the line block is taken into account. |
Is change of running direction |
Specifies whether the activity which is described by this line block item includes a change of the running direction. Is only regarded for user-defined line block items. |
State of charge at end of block item |
State of charge (SOC) of the vehicle referring to a user-defined block item type that is reached at the end of the block item. |
Remaining range concerning time |
Remaining range of coverage at the end of the block item, based only on the time, i.e. without taking the charging and discharging functions at the line block type into account. |
Remaining range concerning length |
Remaining range of coverage at the end of a block item, referring to the length only, i.e. without taking the charging and discharging functions at the line block type into account. |
Charging function value |
Evaluation of the charging function on the block item. The state of charge regarding the user-defined block item type is increased by this value during the course of the block item. |
Discharging function value |
Evaluation of the discharging function on the block item. The state of charge regarding the user-defined block item type is decreased by this value during the course of the block item. |
Table 220: Block item attributes
Each block item is of a certain type (block item type). By default, there are the block item types vehicle journey, empty trip, stand (layover/depot) and layover time in Visum. However, you can also create user-defined block items types. These block item types are recurring activities that you can optionally take into account in the block version. A prime example would be the charging of battery electric vehicles, but also conventional refueling or maintenance activities can be modeled this way (Description of the line blocking procedure with recurring activities). The spatial and temporal interval between these activities can be interpreted as a discharging function. As in the default configuration, discharging can be set as a linear consumption of time and distance of the range or can be made more complex by using the network model for vehicle journey sections and their link attributes. The duration of the activity can be interpreted as charging. The linear part of the charging function is defined by an initial slope. This slope can be defined based on a default duration or it can be freely configured using attributes of the network model, e.g. stop points. If the user-defined block items are activities that are only scheduled sporadically, you can flag them as not mandatory in the block version and schedule them manually in your blocks. The Table 221 shows the attributes of block item types.
Attribute |
Description |
Created by the system |
Specifies, whether the block item is user-defined. |
Default duration |
Default value for the time period of block items of this type (default setting when creating such a block item). |
Default length |
Default value for the length of block items of this type (default setting when creating such a block item). |
Time limit |
Maximum value for the duration between two block items of this type. If a value >0 is specified here, the time elapsed between the occurrence of two items of this type may not exceed this threshold. If this is not the case, the line block check will return a limit fault (Line block check). |
Length limit |
Maximum value for the distance being traversed by a block between two block items of this type. If a value >0 is specified here, the distance traversed between the occurrence of two items of this type may not exceed this threshold. If this is not the case, the line block check will return a limit fault (Line block check). |
Initial gradient of charging function |
Slope at zero point of the charging function, as a formula based on data of the block item. The charging function indicates how the state of charge of the vehicle increases from the start of a block item to its end, depending on the data of this block item. |
Discharging function |
The discharging function formula specifies how the state of charge of the vehicle decreases, depending on the data of the block item. The time period from the start to the end of an activity (represented by a block item) is considered. |