This document presents an outline for a presentation on timing diagrams. It will cover lifelines, timing rulers, state/condition timelines, duration constraints, time constraints, and events. It provides examples of how these concepts are depicted in timing diagrams including lifelines representing systems and viruses, a traffic light lifeline showing states over time, a virus lifeline changing between dormant, propagation, triggering and execution states, constraints for ice melting in 1-6 minutes and waking up between 5:40-6am, and destruction events terminating a lifeline.

1. A presentation on
Timing Diagrams
Presented by Khaled Amirat
Supervised by Pr Abdelkrim Amirat
Department of Mathematics and Computer Science
University of Souk Ahras, Algeria
2017
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2. The layout of the presentation will lead the following outline
Lifeline ( Ligne de Vie ),
Timing Ruler (La regle du temps),
State or Condition Timeline (Etat ou Condition),
Duration Constraint (Contrainte de Durée ),
Time Constraint (Contrainte de Temps),
Events (l'événement),
And some Examples.

3. Timing Diagrams
Timing diagram is one of the four view if the interaction model in
UML interaction diagrams used to show interactions when a primary
purpose of the diagram is to reason about time. Timing diagrams focus
on conditions changing within and among lifelines along a linear time
axis.
They are used to explore the behaviors of one or more objects
throughout a given period of time.

4. Life Line (1)
Lifeline is a named element which represents an individual
participant in the interaction.
Lifelines represent only one interacting entity.
The time flows from left to right.
EX : Lifelines representing instances of
System and Virus

5. Life Line (2)
When the system is in that state, a line is drawn in that band for the
duration of the time the system is in the state. The time axis is linear,
although special notations are sometimes used to indicate long
uninteresting periods of time.
EX Traffic Light

6. Life Line (3)
A value lifeline shows the change of value of an item over time. The
X-axis displays elapsed time in whatever units are chosen, the same as
for the state lifeline. The value is shown between the pair of horizontal
lines which cross over at each change in value. A value lifeline is shown
below.
EX Traffic Light

7. Timing Ruler
A timing ruler is a graduated device for indicating the passage of
time on a timing diagram. The graduations are called ticks and are
typically placed on the lower edge of the diagram frame. Time runs
from left to right. The scale and time units (ticks) depend upon what
the diagram represents and may be sub-second units such as
milliseconds or larger time divisions such as hours, days, months or
even years.

8. State or Condition timeline
Timing diagram could show states of the participating classifier or
attribute, or some testable conditions, such as a discrete or
enumerable value of an attribute.
It shows the changing state of an item over time.
Ex Timeline shows Virus changing its
state between Dormant, Propagation,
Triggering and Execution state

9. Duration Constraint (1)
A duration constraint is a type of interval constraint that specifies
that one or more model elements must conform to a restriction
specified by a duration interval.

10. Duration Constraint (2)
Like any constraint the duration constraint is used when the formal
semantics of an element are insufficient to express some restriction on
the modeled elements. A duration interval defines minimum and
maximum values defining a range, and this range of allowable values is
specified by the duration constraint and applied to one or more
elements. If the constraint does not evaluate to TRUE in a running
system the duration interval is considered to be invalid.

11. Duration Constraint (3)
Ice should melt into water in 1 to 6 minutes

12. Time Constraint (1)
A time constraint is a type of interval constraint that specifies that
one or more model elements must conform to a restriction specified by
a time interval. A time constraint is not the time interval itself but a
constraint, which associates the interval with one or more elements
specifying how it restricts the elements, time semantics.

13. Time Constraint (2)
Time constraint is an interval constraint that refers to a time
interval. The time interval is time expression used to determine
whether the constraint is satisfied.
Time constraint is shown as graphical association between a time
interval and the construct that it constrains. Typically this graphical
association is a small line.

14. Time Constraint (3)
Person should wake up between 5:40 am and 6 am

15. Event Occurrence (General Value)
An event occurrence is both a type of interaction fragment and a
type of message end. Event occurrences mark the points on a lifeline
where events occur. An event occurrence is the basic unit of meaning
in an interaction. A lifeline is used to describe the way an instance, or a
classifier playing a role, changes over time and event occurrences mark
the points on lifelines where messages start or end.

16. Destruction Event (1)
Destruction occurrence is a message occurrence which represents
the destruction of the instance described by the lifeline. It may result in
the subsequent destruction of other objects that this object owns by
composition. No other occurrence may appear after the destruction
event on a given lifeline.
Notation
The destruction event is depicted by a cross in the form of an X at the
end of a timeline.

17. Destruction Event (2)
Virus lifeline is terminated

18. Destruction Event (2)
Timing Diagram Example - Stages of Alzheimer’s Disease

19. Destruction Event (2)
Timing Diagram Example - Stages of Alzheimer’s Disease

20. Thank You
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