NPCR–MERP Diagram Conventions

The Modeling Electronic Reporting Project (MERP) model diagrams are based on the Unified Modeling Language (UML). This document outlines additional conventions used specifically for MERP.

General Conventions

• Diagrams flow from top to bottom.
• Diagrams flow from left to right.
• The version number changes only when major changes are implemented. For minor changes, there is no version change.
• Notes are represented by rectangles with the top right corner folded down.
• The work being discussed is shaded purple.
• General comments or questions are shown in white or purple colors.

Decision Nodes in Activity Diagrams (Workflow and Data Flow Diagrams)

• Text questions are to the left of the decision node.
• All activity diagrams (in general) have one start point and one end point.

Use Case Diagrams

• The first level is represented as a package. A package is a container in the shape of a yellow folder which can contain different model elements such as use cases and other packages.
• Second-level use cases are represented by light blue ovals.
• Each use case is assigned to the first or second level according to its hierarchy.

Activity Diagrams (Workflow and Data Flow Diagrams)

• Decisions are represented by light yellow diamonds.
• Start and end nodes are represented by black circles with a red outline.
• State transition specifications are presented as a guard condition for transition from one state to another.
• Business rules and software requirements are shown in the right swimlane (column) in light blue.
• Horizontal and vertical solid black lines are synchronization bars.

Technicalities and Concepts to Understand the Diagrams

• Domain Diagram: The classes connecting to "Internal and External Data Source" classes are actual data sources, not data coming from those classes.



• Use Case Diagram: The use cases are presented in a hierarchical way. The highest or first-level use case consists of the second-level use case(s) and so on.



• Workflow Diagram: The details presented in this diagram are limited. It is a simple representation of the normal course of events.



• Data Flow Diagram: This is a detailed diagram with all conditions covered for a use case or process. It presents exceptions, alternate courses of events, and business rules for the normal course of events in the process.



• All Diagrams: When reading a diagram, pay attention to the direction of arrows.