UML state machine diagrams illustrate the states and transitions of an object in response to events. A state represents the condition of an object at a moment in time between events. A transition between two states occurs when an event happens, which may cause actions to fire or require conditional guards. States can be nested, with substates inheriting transitions from the superstate. Pipelining is a technique that decomposes a process into sub-operations that execute concurrently on different data in specialized pipeline segments, overlapping computations to improve efficiency.

1. Software engineering
Presented by: Nourhan Tarek
PHD candidate at Ain Shams University
Masters of science in Electrical engineering at
Ain Shams University

2. 1- UML State Machine Diagrams and Modeling
State Machine Diagram
Illustrates the interesting events and states of an object and the behavior of an object
in reaction to an event.
Event: significant or noteworthy occurrence.
• E.g., telephone receiver taken off hook.
State: the condition of an object at a moment in time (between events).
Transition: a relationship between two states; when an event occurs, the object
moves from the current state to a related state.

3. 1- UML State Machine Diagrams and Modeling
Transition Actions and Guards
A transition can cause an action to fire.
In software implementation, a method of the class of the state machine is
invoked.
A transition may have a conditional guard.
The transition occurs only if the test passes.

4. 1- UML State Machine Diagrams and Modeling
Nested States
A state may be represented as nested substates.
In UML, substates are shown by nesting them in a superstate box.
A substate inherits the transitions of its superstate.

5. Presented by: Nourhan Tarek
PHD candidate at Ain Shams University
Masters of science in Electrical engineering at
Ain Shams University
Computer architecture

6. 2- Pipelining
It is a technique of decomposing a sequential process into sub-operations.
Each sub-operation is executed in a special dedicated segment that operates
concurrently with other segments
The overlapping of computations is possible by associating a register with segments
in the pipeline
The registers provide isolation between each segment, so that each segment can
operate on distinct data simultaneously

7. 2- Pipelining
𝐴𝑖 ∗ 𝐵𝑖 + 𝐶𝑖, 𝑖 = 1,2, … , 7
Sub-operations are:
The behavior of the pipeline can be
illustrated by a space-time diagram

8. 2- Pipelining

9. Thank you