Author: Tim Weilkiens

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What is a model?

Could you easily answer this question? Is a document a model? Why not? Most references define a model or properties of a model like this A model is a representation of something. It captures not all attributes of the represented thing, but rather only those seeming relevant. The model is created for a certain purpose…
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Product Tree Forest Fire Detection System Non-tree Style

Two Kinds of Patterns

Did you know that you use patterns every day? It’s a very powerful mechanism and much more powerful when they are explicit and known. A pattern describes a proven solution for a problem. Every experienced engineer has a huge set of patterns. Think about your daily work. If you must solve a problem that you’ve…
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Nordic Systems Engineering Tour

The Nordic Systems Engineering Tour

I proudly present the Nordic Systems Engineering Tour – a one-day conference event at three different locations in three days. From Hamburg via Copenhagen to Stockholm. Together with Erik Herzog I had the idea to boost systems engineering in northern Germany, Denmark, and Sweden. Why these countries? The answer is easy: Erik lives in Sweden…
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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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