MBSE with CORE 100821

Identifying Composite Requirements

Our objective is single, verifiable Requirements . We can identify those Requirements that must be refined further. Requirements R.1, R.2, R.2.2, R.2.3, and R.2.7 contain multiple requirement statements meaning they are “composite” 1. Control-click on the indicated Requirements 2. Right-click and select Set Attribute 3. Select “Type” from the attribute drop - down to set the type attribute 4. Select “Composite” from the Value drop - down 5. Click OK

The Set Attribute command can set an attribute from anywhere (without opening the property sheet) and can be used to set the same value for multiple elements at once

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Decomposing Composite Requirements

Composite requirements must be broken down into single, verifiable requirement statements • Break up requirements without changing the meaning • Maintain traceability to originating requirement (and indirectly the source document) Steps to create new child requirements from composite parent requirement 1. Duplicate requirement specifying a new name 2. Edit Description in new child requirement 3. Set child Type attribute to “nil” 4. Relate child to parent using refines relationship 5. Renumber composite requirement to automatically number new children

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MBSE with CORE