Author: Tim Weilkiens

Death of the Use Case

Criminal Scene Investigation: Death of the Actor and the Use Case

The previous posts Death of the Actor and Death of the Use Case reported about two serious killings in the modeling scene. Many eyewitnesses commented the report. Now it is time for a short review. First the good news: The concepts Actor and Use Case survived the massacre. I’ve seen them still alive and very active…
Read more Most popular UML modeling tools

Most popular UML modeling tools

Although UML is a modeling language for software, it is sometimes also used in systems engineering projects. Since SysML is a kind of a profile you can define your own SysML stereotypes to use a UML modeling tool for SysML modeling. Please click here:  

Death of the Use Case

The Death of the Use Case

After killing the Actor in The Death of the Actor my next victim is the use case. Don’t use Use cases in SysML (or UML) models anymore! My statement seems to be revolutionary or stupid (or both). Just to be not misunderstood, I’m not against the concept of use cases and actors. I believe that the…
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Trophy - Popular SysML modeling tool

Most popular SysML modeling tools

Please click here: Unfortunately I have technical problems with the WordPress plugin and can’t show the list embedded in this blog post.

Why MBSE matters?

Many companies deal with the challenge to introduce MBSE. As a consultant for MBSE I often ask my customer about their objectives to apply MBSE techniques. The answers are more or less the same: the systems are getting more complex and at the same time we must decrease costs and time-to-market and increase the quality.…
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SysML activity tree with object nodes

Hidden feature of SysML – Activity Trees

It is very well unknown and I know only a single modeling tool that explicitly supports it: the SysML activity tree. Although it is very useful and supports common systems engineering practice. What am I talking about? You may know use cases and activities to describe the use case flows. Simply spoken they describe the…
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Structure of a SysML model with metadata Issues, Notes, and Sketches

Metadata in the model

Models do not only contain the “real” artifacts for your system, but also additional auxiliary information like notes, issues, images, and so on (metadata). It is very useful to store such information at the place where you need or create it. Switching from one tool to another is a hurdle that prevents people from looking…
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Extended system context with SysML - FFDS example

How to model an extended system context with SysML

The extended system context describes the system interfaces and the detailed connection to the system actors and to the internal parts of the actors. In the previous post How to model a simple system context with SysML I’ve written about system context in general and the simple edition of system context that is simply spoken just…
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System context Forest Fire Detection System with SysML

How to model a simple system context with SysML

The system context defines the system boundary and all system actors – humans and external systems – that interact with the system under development. It is one of the most important parts of the system model. Many artifacts of the system specification and architecture are relative defined to the definition of the system. Every system behavior…
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SYSMOD Zigzag Base Architecture - FFDS example

The Base Architecture

How to relate requirements and architecture on different abstraction levels The SYSMOD zigzag pattern describes the different levels of abstractions and the relationship between requirements and architecture. Your system requirements do not start at the very top of the levels, i.e. they already include some technical decisions. The base architecture is the architecture one level above…
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