14:01: UseCases in SysMLv1

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Tutorial
TRAIL: Webel's ultimate guide to Systems Modeling Language (v1) with MagicDraw/Cameo
UML keywords
UseCase
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This topic section is deliberately NOT covered in detail in the online version of this tutorial
For full coverage of this topic section please attend our live course:
Course: Model-Based Systems Engineering with OMG Systems Modeling Language® (v1) and the MagicDraw/Cameo (CATIA Magic™) tools for SysML
Webel: MBSE: SysMLv1: Prefer a custom «actor» extension of a Block (such as the non-normative External) over UML-style Actor for use as parts in IBDs and on allocation swimlanes. You can also have a Trace from a block-based «actor» to a UML-style Actor.
This section of the larger online version of this tutorial trail is limited to a few observations concerning using UseCases in SysML, it is not a full introduction to UseCase diagrams. There are however some examples of UseCase Diagrams in the Hybrid SUV sample problem tutorial trail, and many examples of UseCases and how to create scenario diagrams for them throughout the site, accessible from these collated Webel Best Practice note pages:
Webel: SysMLv1: Overview of annotated Diagram Slides and Note pages related to UseCases and their combination with a System (of interest), SystemContext, and drill-down to scenario Sequence Diagrams (Interactions) and Activity Diagrams.
Start section here
UseCases - UML subject vs SysML Block

Slides in this section

If you want to navigate the entire section including the additional explanatory text click on the title link of the first slide to view the full slide page, then use the next links to move through the slide pages. If you just want to view the slide images only in sequence, click on any slide to view it larger in a viewer, then click again to move through each slide in this tutorial trail section.
UseCases - UML subject vs SysML Block
Package, Model, or SysML Block as UseCase owner
GOTCHA: UML Component «subsystem» vs non-normative SysML «subsystem»
Next trail section
15:01: The Allocate relationship and functional analysis
SysMLv1: MagicDraw/Cameo: INTRINSIC GOTCHA: Care must be taken with ownership of Activities used as UseCase scenarios vs the ‘subject’ of the UseCase. Make sure you don’t get an Activity ‘context’ mismatch! It's up to you to manage it as intended.
SysMLv1: UseCase scenario representations: On use of Activity Diagrams with swimlanes and/or Sequence Diagrams (Interactions): Actor or block-based custom «actor» on 1st (typically left) Lifeline/Swimlane, System/Subsystem on 2nd Lifeline/Swimlane
Webel: MBSE: SysMLv1: Prefer a custom «actor» extension of a Block (such as the non-normative External) over UML-style Actor for use as parts in IBDs and on allocation swimlanes. You can also have a Trace from a block-based «actor» to a UML-style Actor.
Webel: SysML for MBSE: The frequent recommendation that each UseCase have at least one "primary" scenario is a very useful and highly recommended CONVENTION (only). But it is not actually enforced by the SysML1.7 or UML2.5.1 metamodels or specifications.