28-09-2012, 01:04 PM
Data Flow Diagrams
DFD Examples.ppt (Size: 394 KB / Downloads: 403)
Create a list of activities
Construct Context Level DFD(identifies external entities and processes)
Construct Level 0 DFD (identifies manageable sub process )
Construct Level 1- n DFD (identifies actual data flows and data stores)
Check against rules of DFD
Creating Data Flow Diagrams
Create a list of activities
Old way: no Use-Case Diagram
New way: use Use-Case Diagram
Construct Context Level DFD(identifies sources and sink)
Construct Level 0 DFD (identifies manageable sub processes )
Construct Level 1- n DFD (identifies actual data flows and data stores )
DFD Example: Bus Garage Repairs
Buses come to a garage for repairs.
A mechanic and helper perform the repair, record the reason for the repair and record the total cost of all parts used on a Shop Repair Order.
Information on labor, parts and repair outcome is used for billing by the Accounting Department, parts monitoring by the inventory management computer system and a performance review by the supervisor.
External Entities: Bus, Mechanic, Helper, Supervisor, Inventory Management System, Accounting Department, etc.
Key process (“the system”): performing repairs and storing information related to repairs
Processes:
Record Bus ID and reason for repair
Determine parts needed
Perform repair
Calculate parts extended and total cost
Record labor hours, cost
DFD Examples.ppt (Size: 394 KB / Downloads: 403)
Create a list of activities
Construct Context Level DFD(identifies external entities and processes)
Construct Level 0 DFD (identifies manageable sub process )
Construct Level 1- n DFD (identifies actual data flows and data stores)
Check against rules of DFD
Creating Data Flow Diagrams
Create a list of activities
Old way: no Use-Case Diagram
New way: use Use-Case Diagram
Construct Context Level DFD(identifies sources and sink)
Construct Level 0 DFD (identifies manageable sub processes )
Construct Level 1- n DFD (identifies actual data flows and data stores )
DFD Example: Bus Garage Repairs
Buses come to a garage for repairs.
A mechanic and helper perform the repair, record the reason for the repair and record the total cost of all parts used on a Shop Repair Order.
Information on labor, parts and repair outcome is used for billing by the Accounting Department, parts monitoring by the inventory management computer system and a performance review by the supervisor.
External Entities: Bus, Mechanic, Helper, Supervisor, Inventory Management System, Accounting Department, etc.
Key process (“the system”): performing repairs and storing information related to repairs
Processes:
Record Bus ID and reason for repair
Determine parts needed
Perform repair
Calculate parts extended and total cost
Record labor hours, cost