Chapter 4: Internal Block Diagrams Flashcards
What is: Internal Block Diagram
Like a BDD, this diagram is a static (structural) view of the system or one of its parts.
Unlike a BDD, this diagram does not display blocks; it displays usages of blocks—that is, the part properties and reference properties of the block that is named in the header of this Diagram.
Conveys how the parts of a block must be assembled to create a valid instance of the block.
T/F: IBDs and BDDs provide complementary views of a block
T, A BDD lets you first define a block and its properties. Then you can use an IBD to
display a valid configuration of that block—a specific set of connections among the block’s properties.
Because of this close relationship, you often create IBDs and BDDs in tandem for various stakeholders at different points in the system life cycle.
List the allowable Model Element type for an IBD
The allowable Model Element Type for this Diagram is:
- block
What additional information can be provided within an IBD that cannot be in a BDD?
The specific connections among the internal part properties and their connections to the external reference property.
You use connectors between properties to convey that assembly.
T/F: A part/reference property within an IBD has a different meaning as a part/reference property in the parts property in a BDD
F, A part property on an IBD has the same meaning as a part property in the parts compartment of a block on a BDD: It represents a structure that’s internal to the block named in the IBD header—a structure that the block is composed of.
A reference property on an IBD has the same meaning as a reference property in the references compartment of a block on a BDD: It represents a structure that’s external to the block named in the IBD header— a structure that the block needs for some purpose, either to invoke behaviors or to exchange matter, energy, or data.
What is: Connector
A connector between two properties on an IBD conveys that the two structures will have some way to access each other within a correctly assembled and operational system. You can optionally specify a name and type for a connector to convey additional information about the medium that connects those two structures.
What is the string format of a connector
The connector name is optional and modeler defined.
The type is also optional, but if you choose to specify one, it must be the name of an association you’ve created between two blocks somewhere in your system model. That association must relate the same two blocks that tvpe the two properties at the ends of the connector.
How: is a connector displayed
The two connected properties can be part properties, reference properties, or one of each.
If the two connected properties have compatible ports—standard ports or flow ports—you can optionally attach the connector to those ports instead of to the properties directly. Doing so would convey that those properties are connected at specific points of interaction on their boundaries.
T/F: You can display ports on the frame of an IBD.
You can display ports on the frame of an IBD. Such ports represent points of interaction on the boundary of the block that the IBD represents—the one named in the diagram header.
To convey that an internal part of a composite block is connected to the composite via
some point of interaction at its boundary, you can connect a port on the frame to a port on a part property. This design conveys that an instance of the composite structure can pass requests for behaviors and item flows either from external clients to that internal part or from that internal part to external providers.
What is: Item Flow
An item flow represents a type of matter, energy, or data that flows between two structures within a system.
How: is item flow displayed
The notation for an item flow on an IBD is a filled-in triangular arrowhead on a connector that joins two flow ports (see Figure 4.7). The type that the item flow represents appears in a label near the arrowhead on the connector; the label must contain the name of a block, value type, or signal that exists somewhere in the system model.
The type that an item flow represents must be compatible with the types of the flow ports at either end of the connector.
What is: Dot Notation
Dot notation enables you to express a structural hierarchy compactly in the form of a text string.
