This DFD shows the processes that make up the Manage Emissions facility within the Manage Traffic function. These processes monitor atmospheric pollution levels and vehicle emissions and provide details of those that are above pre-set limits to other facilities.
The key points about the facility are as follows:
There are ten processes in this DFD:
a)Provide Emissions Operations Personnel Interface (1.5.1)
b)Process Pollution Data (1.5.2)
c)Update Pollution Display Map Data (1.5.3)
d)Manage Pollution State Data Store (1.5.4)
e)Detect Vehicle Emissions Levels (1.5.5)
f)Detect Pollution Levels (1.5.6)
g)Process Vehicle Emissions Data (1.5.7)
h)Manage Emissions and Pollution Reference Data Stores (1.5.8)
i)Manage Emissions Archive Data (1.5.9)
j)Manage Emissions State Data Store (1.5.10)
Pollution levels are detected at the roadside by process (f), in the wider geographic area by process (b) and from vehicles by process (e). The data from these three processes is supplied to process (d) which maintains and stores the data for access by the traffic operations personnel through process (a). Process (d) also supplies a copy of the stored pollution data on request to the Manage Demand facility - see DFD 1.4. The wide area and vehicle pollution data is also supplied to process (g) for loading into the log of pollution data. A copy of this is periodically sent to the Manage Archived Data function - see DFD 8.
The need for are pollution levels to be reported as incidents by process (b), or vehicle drivers and the law enforcement agency notified of high pollution by process (e), depends on the pollution reference data. This is contained in a store managed by process (h). It can be monitored and updated by the emissions operations personnel through process (a). The output of data by process (a) may be against a background of a digitized map supplied by process (c).
Although these processes are shown as a coherent group, they can be implemented in part if needed. For example, the monitoring of either area or vehicle pollution can be omitted. Data about the ownership of polluting vehicles is obtained from the relevant Department of Motor Vehicles by the process responsible for law enforcement - see DFD 5.4.
Parent DFD: 1 - Manage Traffic
PSpecs in the DFD: