1. Professor Peter Campbell
Panel/Workshop SE for National Electricity System

2. Background
The application being presented is from work sponsored by the Australasian Centre for Rail Innovation (ACRI)
Application of MBSE techniques that assist stakeholders/users in examining the impact of the introduction of new technologies into heavy rail organisations
Development of a “Portal” based architecture based on “concerns”
Modelling has been based on a tailored version of the UAF

3. Addressing Rail Organisation Concerns
Applications of MBSE techniques are able to do more than just capture information of and about a system
Enables communication of concepts between stakeholders
Prompts users for content to be developed and subsequently captured
Can be structured to allow easy navigation through large complex representations
But poor application of MBSE can result in
Wasted effort,
Poor information dissemination, or
Models discarded because of lack of usability
Care is needed to ensure the technology is applied appropriately

4. Multi-user Approach Typically a multi-user model
Each user has a portal to access the information which they need
Shared model spaces to enable provision of only specific (restricted) information to external organisations
Organisation-specific model
Needed as this model is intended to be used by several rail organisations that need to customise for their situations
General model
Used to roll out information to all organisations
Contains general structures

5. Unified Architecture Framework Coverage

6. Need for a Formalised Approach
Needs a formal approach to identify:
What information needs to be modelled
To what level of detail
What information needs to be being shared
By whom
With whom
In a manner that is replicable and flexible to the evolving needs of the stakeholder (users)
We found that going back to the underlying principles that UAF was based upon provided the necessary structure:
ISO/IEC – the Architecture Description Standard
This allowed us to build a model that has the stakeholder needs explicit in the way the information is both captured and presented

7. Defining Viewpoints
Architecture Frameworks are the generic structures that may be populated when creating a model of a system
Using ISO 42010, viewpoints are created to frame the concerns of the framework’s stakeholders.
Concerns can be considered to be the questions a stakeholder will ask of the model (or address using the model)
UAF can define a large number of viewpoints

8. Defining Architecture Descriptions
Architecture Descriptions are then developed by populating the Framework
Model views are populated viewpoints that can then be used to address stakeholder’s concern(s)
This creates an explicit relationship between the model content and the people who will use it
This structure can then be leveraged to further tailor the model

9. The Process
Identify the stakeholders and concerns in relation to each of the technologies considered in the tool;
Identify the processes needed to address the concerns;
Convert the processes into detailed tasks and allocate the viewpoints to each task;
Development and description of the viewpoints;
Examine the viewpoint needs (Identification of the information types required by stakeholders to enable them to address their concerns);
Identify data structures required to support the viewpoint;
Describe the manner in which the information will be presented and managed
Identify interdependencies between viewpoints.
Step 1 is intended to provide understanding of the needs, identify the stakeholders who will use the model, their concerns and questions that need to be answered.
Step 2 examines how these questions need to be addressed.
Step 3 converts the process into a discrete set of viewpoints and identifies how these viewpoints need to be arranged.
Step 4 develops the viewpoints so that they contribute to addressing the various concerns.
Step 5 integrates all viewpoints into a coherent AF that can be fully traceable back to the stakeholder’s needs.

12. But Usability also Requires Navigation
How will users access the information pertinent to them?
How will users be guided through or around areas which are shared?

13. Model Navigation to Help Address Concerns
Merely allowing users to “find their way” is unsatisfactory
Therefore:
Customised portals must be created for each stakeholder/user to access their viewpoints
Each concern is then presented so the user can select what aspects they are currently interested in, and
Navigation is created to guide the stakeholder to the information that addresses their concerns
Navigation is implemented either:
By directly linking objects in models to destination diagrams;
Better for linear processes
By capture of processes in activity diagrams and linking the diagrams to the various concerns
Better for branching processes or areas where different perspectives may be desired

14. Example – Competency Changes with the Introduction of Drones for Overhead Wire Inspection

15. Summary
Applications of MBSE need to be focused on the information needs of the people who will use the model, and be usable
This presentation shows how to utilise activity diagrams to capture the stakeholder processes and present views in a suitable order while maintaining the ability of stakeholders to move around the model as necessary
ISO provides a useful relationship between the content and how it addresses the concerns of the stakeholders
This relationship can be re-used to identify the appropriate views to be populated based on the concerns to be addressed
ISO however doesn’t consider the order in which to present the views or how to guide the stakeholder in the use of the modelled information
While some consider the freedom of models to “go where desired” as a positive, it can have issues:
Unclear what the stakeholder has viewed (which may cause oversight)
Some views constrain others which stakeholders need to be aware of

16. Discussion