• Системная инженерия - прецедентный подход

• Системный прецедент

• Инженер требований

• Инженер требований

• Выполнение анализа "на черный день"
• Декомпозиция диаграммы деятельности
• Извлечение поведения прецедента на основе состояний
• Извлечение сценариев прецедента
• Определение поведения прецедента на основе состояний
• Определение портов и интерфейсов
• Определение сценариев прецедента
• Создание диаграммы деятельности (черный ящик)
• Формирование функционального потока прецедента

• Выполнение анализа "на черный день"
• Определение портов и интерфейсов
• Определение системного контекста прецедента

Elements of this diagram are instances of SysML blocks that represent the use case and its associated actor(s). 

The Use-Case Block is the structural representation of a use case defined in the use-case diagram. It is used to represent the formal specification of the system behavior for the use case and acts as a location for the operations/functions that the use case employs. The Use-Case Block communicates with relevant Actor Blocks via ports and associated provided and required interfaces.

An Actor Block is the realization of an actor that was previously identified in a system use case diagram. An actor block represents a person, or system that is external to the system under development, that interacts with the system under development by providing the inputs to, and receiving outputs from the system under development.

A Use-Case Block can be represented as:

• A block on a Block Definition Diagram;
• The classifier of a part on an Internal Block Diagram;
• The classifier of a lifeline on a Use-Case Black-Box Sequence Diagram

An Actor Block can be represented as:

• A SysML block on a Block Definition Diagram.
• The classifier of a SysML part on an Internal Block Diagram.
• The classifier of a SysML lifeline on a Sequence Diagram.