Category Archives: System requirement

Specification for A-SPICE or ISO 26262

In the A-SPICE, there are various kinds of requirements; System Requirement, System Design, SW Requirement, SW architecture, SW Unit design. ISO 26262 requires similarly .

To manage traceability rigid decomposition of requirements into these are beneficial.

You can integrate all kinds of requirements into one documents. Then you will face a fact that managing traceability is not a easy task.

To specify, it requires different kinds of technical skills. It is not related engineering knowledge. It is closely related to logical thinking and writing technique.

You may wonder if I emphasize that writing technique is core skill to comply engineering process, because writing technique seems not to be related to engineering knowledge.

To Know it and to explain what you know are different. Sometimes it takes much time or infinite time to understand a document, because it is hard to understand.  Requirement obfuscation is not good for team’s productivity and team’s communication. It also makes hard to achieve A-SPICE or functional safety standard.

So, engineers are required to learn how to specify requirements. It shall be educated.

To engineers, please do not blame readers because of their poor engineering knowledge, and do not think that it is a reason they do not understand your document. It is not good.

For reference,

  1. Requirements_Engineering_Management_Handbook explains how to specify requirements.
  2. safety driven model based system engineering methodology(Part 1, Part 2) shows example.
  3. AUTOSAR Use Case Example CP Release 4.3.1


Learning to work with user stories

Learning to work with user stories

Learning to work with user stories
— 사이트 계속 읽기:

use case diagram or user story is considered in the business level, and if I map to development process, it is very close to ConOps or SOTIF level.

In some cases, we can try to use user story to sub-system’s development process, then it would be hard to make fit. Anyway learning various approach helps me to be more flexible, and have more agility. (I can use ‘agile’ but I didn’t use it because ‘agile’ become very popular, and many people use it without any knowledge)

Guide to Functional Decomposition – ppt video online download

Contents What is functional decomposition? Why is functional decomposition used? When is functional decomposition used? How to perform functional decomposition A sample functional decomposition – step 1 A sample functional decomposition – step 2 A sample functional decomposition – step 3 What level to decompose functions to? Further assistance

소스: Guide to Functional Decomposition – ppt video online download

It is posed for functional FTA.