Block Definition and Internal Block Diagrams Flashcards
What can a block define?
- a type of logical or conceptual entity
- physical entity
- hardware, software, or data component
- person
- a facility
- an entity that flows through the system
- an entity in the natural environment
Is a block a type or a usage?
A type that owns a set of features (structural and behavioral) that describe the characteristics of an instance.
What is the symbol of a block?
a rectangle that is segmented into a series of compartments:
- name compartment (mandatory)
- parts
- operations
- value properties
- ports
What are part properties?
Describe the composition hierarchy of a block and define a part in the context of its whole.
What are value properties?
Describes quantifiable physical, performance, and other characteristics of a block such as weight or speed. It is defined by a value type that describes its valid range of values and quantity kind (length) and its units (inches). Can be related using parametric constraints.
What are properties?
Structural features of a block. THey have a type that defines its characteristics, which may be another block or something more basic like an integer.
What are the 3 categories of block properties?
- part properties: describe the composition of a block into its constituent elements.
- reference properties: properties whose values refer to parts of other blocks.
- value properties: describe the quantifiable characteristics of a block (weight, velocity)
What kind of properties does a properties compartment of a block contain?
any kind of properties
What is a composition relationship?
a whole-part relationship
What is the diagram kind of a block definition diagram, and which model elements can it represent?
Diagram kind: bdd
model elements: package, block, constraint block
What is the diagram kind of an internal block diagram and which model elements can it represent?
diagram kind: ibd
model elements: block
Which type of property is used to describe composition relationships between blocks?
Part properties describe the describe the decomposition of a block into its constituent elements.
What is the commonly used term for properties with a lower multiplicity bound of 0?
A lower bound (min instances) of 0 is called optional because the instance is not obligated to include any instances of the block at the part end.
What is the default interpretation of the multiplicity for both ends of an association when it is not shown on the diagram?
value of 1 is assumed
Give 2 situations in which the use of role names for the part end of a composite association should be considered
(p 148)
Names are used to distinguish 2 parts with the same type (block)
A name is given to a part when it does not adequately describe the role the part plays
Give 2 situations in which the use of role names for the part end of a composite association should be considered
(p 148)
Names are used to distinguish 2 parts with the same type (block)
A name is given to a part when it does not adequately describe the role the part plays
How are parts shown on an internal block diagram?
(p 147)
parts compartment of a block or as an association end, but not both. also as a box symbol with a solid boundary within the frame of the ibd
What does the presence of a connector between 2 parts imply?
(p 150)
The parts interact with each other in some way.
What are the 2 graphical mechanisms that can be used to represent properties nested more than 1 level deep on an ibd?
(p 156)
The nested parts can be represented by showing part symbols within part symbols
dot notation