Microsoft Access database - Main tab - Stations management options
Opens the Stations table tblBases for editing.
Field BaseId is the key by which a station is referenced, e.g. “A01”.
Field BaseName is the ‘real’ name of the station.
Field OverBorder defined whether this station is a user’s own station or is over the border.
Fields Easting and Northing are the coordinates of the station.
Field StaffSystem shows which Staffing System this station has – this is a foreign key from Staffing.
Field MaxAppliances is an optional field which specifies the maximum number of appliances the station can accommodate – see Station Capacity - Vehicle Class.
Field SelectionOrder is an optional field, if set, this will control the order in which the station columns will appear in the spreadsheets created by Predict Demand and Unit Utilisation by Station.
Opens the Staffing table tblStaffingSystems for editing.
Field StaffingId is the key by which the rows are referenced.
Field Staffing is the user-visible name, e.g. “Retained”.
Field StaffingComment can hold a more meaningful comment.
Field StaffingReactionTime holds the reaction time for this type of staffing system. In modelling this is used in the calculation of appliance assignments.
Opens the Shifts table tblShiftSystems for editing.
Field ShiftId is the key by which these records are referenced.
Field ShiftName is the user-visible name and can be seen in drop-downs when creating a Resource Set for modelling.
Field ShiftComment can hold a more meaningful comment.
Fields ShiftStart and ShiftEnd are the times of day the shift starts and ends. These are used to determine the availability of appliances from a resource set in modelling.
Opens a form StationCapacities for editing stations’ (Bases’) vehicle capacities.
It is necessary for each vehicle type to define an upper limit of how many can be accommodated at each station to be used in a station set in modelling.
Modelling is allowed to place vehicles at stations up to the defined capacity. If no capacity is set for a class modelling assumes that no vehicles of that class can be allocated to a station.
Note: To allow modelling to place, for example, up to three TypeA appliances or up to three TypeB appliances or up to three TypeC appliances at station X it is necessary to set the capacity of each of these three Vehicle Classes to three for Station X. Theoretically this would allow the modelling to place up to nine appliances at X, i.e. 3 of A, 3 of B and 3 of C.
But in reality station X may be only available to accommodate four appliances. This can be enforced by setting MaxAppliances in Stations. Thus modelling will be able to place up to a maximum of four appliances.
Workload Modeller includes a Standby Cover feature, i.e. when a station becomes empty an appliance from another station can be moved to that station so it can respond to incidents whilst its own appliances are busy.
The Stations table, tblBases, includes an integer column: CoverSuppliedAfterMins. This defines the number of minutes a station can be empty before a standby appliance will be moved to it. It can be set to any integer number or null (blank).
For example:
| Value | meaning |
| Null (blank) | This station does not receive standby cover. This is the default when the database is upgraded |
| 0 | The station will receive a standby appliance immediately it becomes empty, i.e. after 0 minutes. |
| 10 | The station will receive a standby appliance 10 minutes after it becomes empty - provided it is still empty 10 minutes later. |
Setting up CoverSuppliedAfterMins
When creating an appliance set it is possible to include unallocated appliances, i.e. are not allocated to any station. These are allocated to stations by Workload Modeller as part of the modelling process.
Therefore, the Standby Cover feature will only start when:
Standby Cover will:
A station is deemed to be empty after an appliance based at that station is assigned to an incident if the station then has no general purpose appliances available.
Note: ‘Available’ also means on-shift, i.e. a station with a general purpose appliance will be deemed to be empty if that appliance is off shift at the time of the event.
The nearest station is determined by a straight-line distance.
When an appliance is allocated as standby cover for a station it is effectively moved to that station to respond to incidents.
It is released from its standby cover and reallocated to its ‘home’ station as soon as one of the covered stations’ general purpose appliances is freed up. If the covering appliance is attending an incident when this happens then it will return to its home base when it is released from the incident it is attending.
An additional table is created as part of a Turnout model’s output. A model called ‘Test’ will now have its data in the following tables:
| Model output | Table purpose |
| tblMC_Test | Holds the model’s cover moves |
| tblMO_Test | Holds the model’s responses to callouts (appliance requests) |
| tblMR_Test | Holds the model’s resources – in their ‘home’ locations |
A Model's Output tables
A sample of a table of model cover-moves is shown below.
Note: the field CoverAction can have the following values:
- ASSIGNED – records when a vehicle was moved to cover a station and which stations are involved. The ‘SuppliedAfter’ value is also included.
- RELEASED – records when an appliance was released from its cover assignment.
- NONE AVAILABLE – shows that no Standby cover was available, i.e. no station could provide standby without itself becoming empty.
Model Standby Cover Appliance Moves
Note: Standby Cover moves are also included in the overlay created by the option ‘Create overlay showing model allocations’.
These can be most easily seen by applying a filter to that overlay, for example:
Exists("CoverSuppliedAfterMins&")
The following are current limitations of the Standby Cover feature:
Currently ‘nearest’ has to be determined by a straight-line as there is no station-to-station route costs in the route-cost database.
Travel times are not currently factored in, i.e. the time taken for the standby pump to travel to and from the station it is covering is ‘ignored’. This could be rectified when station-to-station times are added into the route cost database.
Standby Cover is not included in the ‘Predict’ command. This is intentional as Standby Cover masks the true demand at a station.
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