Operational Analysis - Actors and Entities

Arcadia
1

Hi,
I am a beginner with this method, and I know very little of SE.
I am in a project where I am designing a system of a simulation testbed.
In this particular scenario, there is one stakeholder (Infrastructure Manager) that has three departments that do the analysis of a simulation data - new trail line.
One department gets the data from a different stakeholder. Lets call it Department 1. They review the new trail line data, and send it to Department 2. The department 2, does thorough analysis and runs the simulation. Department 3 , reviews the final report.
What would you define the actors here, and the entities. I defined the departments as actors, and Infrastructure Manager as Entity, and contained them in.
For the further modelling, in System Analysis, do I include the Infrastructure Manager, or only the actors?

As I quite couldn’t understand the System Functions, would you say this is correct:
Capability - analyse data; System Functions - Cross-check data with database; Cross-check data with XYZ tool, etc. And those System Functions to be broken down to : Analyse Danger points; Analyse 2D track design, Validate location points, etc.
Also just to add one more thing instead of opening a totally new thread
When I obtained all System Functions and tried to do the SFBD, I wanted to take a SF and contain it in another SF, but Capella doesn’t allow me.
What could be the problem?
Thank you in advance!!

2

+++ In the System Analysis, I added new Actor - New Design.
as it is the object these departments interact with.
Update: It’s not capability, it is Activity.
As for Operational Capability - Validate new line; Review new line.
And in the System Analysis : Validate new line,; Analyse design data;, edit design;, perform functionalities;, review design;.

3

Hello,
In Operational Analysis, Operational Entities represent stakeholders, and Operational Actor is a special kind of stakeholder that is a human (that’s why it cannot be decomposed
). In your example, “Departments” seem to me more like Operational Entities. If in a given department there is a specific person performing a specific activity (e.g. a guy who is the only one that knows how to run simulations), you may want to decompose further and define this Operational Actor. But if it is not relevant for your analysis, you don’t need to.
System Functions are completely different from Operational Activities. They represent what the system does, whereas the Operational Activities represent what the stakeholders do, regardless of the system. The goal of the System Analysis is hence to determine what the system shall do to contribute to fulfill the stakeholders expectations. That means that you may have Operational Activities that are realized through exchanges between an Actor and the System, in which case several Functions (some allocated to the System, others to the Actor) will realize the Operational Activity.
Regarding your SFBD issue, you should probable create a new post in the Capella forum with some screenshots.
Hope it helps,

2 Likes
4

Thank you!
Just to make sure, does the system need actors? Or can they be left out and go with entities only?
Yes, I do agree that the departments are entities, but I’ve seen in a tutorial that sometimes are put as actors, for example “Regulatory bodies” was put as an actor.
Thanks, sure will post in Capella forum for the other issue.
Regards

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I’m not quite sure we share the same definitions of Actor. In Arcadia Systems Analysis perspective, any entity/stakeholder that is external to the System of Interest (i.e. the System) is represented by an Actor. Hence an Actor can be a human, an organization, an equipment, the environment, … Is this definition aligned with your understanding?
Following this definition, all Actors shall be considered in System Analysis, so that the interfaces between the System and its context of operation (the Actors) can be defined. Of course, when you will define the architectural design of your System (through Logical and Physical Architecture perspectives) you may find new Actors that emerge as a consequence of e.g. the technological choices you will do.