These slides can be reused as they are according to the CC BY 4.0 license. Here's the paper describing this pattern: http://ceur-ws.org/Vol-2459/pattern1.pdf Here's the pattern on the ODP catalogue: http://ontologydesignpatterns.org/wiki/Submissions:RecurrentEventSeries In these slides is presented an Ontology Design Pattern for modeling events that recur regularly over time and share some invariant factors, which unify them conceptually. The proposed pattern appears to be foundational, since it models the top-level domain-independent concept of recurrence, as applied to a series of events: we refer to this type of events as recurrent event series. The pattern relies on existing patterns, i.e. Collection, Situation, Classication, Sequence. Indeed, a recurrent event is represented as both a collection of events and a situation in which these events are contextualized and unied according to one or more properties that are peculiar to each event, and occur at regular intervals.

1. 1 University of Bologna, IT
2 STLab, ISTC-CNR, IT
Add authors
Valentina Anita Carriero
Aldo Gangemi
Andrea Giovanni Nuzzolese
Valentina Presutti
WOP @
ISWC2019
Auckland, NZ
1, 2
1, 2
1, 2
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2. What is a recurrent event?
In 1917 Amedeo Modigliani creates an
oil painting depicting Hanka Zborowska Art Biennale is held biennially
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3. What is a recurrent event?
Art Biennale has been held biennially, since 1895,
and has:
• the Biennale Foundation as event organizer
• Venice as event place
• the promotion of new contemporary art trends
as mission
• a time period of ~2 years between two
consecutive occurrences
1895 1897 1899 2019[…]
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4. But also...
the Nobel Prize Award
ceremony
Carnival
periodical team
meetings
Christmas
Ramadan
International
Women's Day
movie showtimes
Birthday
bus timetable
physiological needs
seasons medical ultrasound
during pregnancy
air conditioner
filter cleaning
traditional
ceremonies
cultural events
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5. Looking around
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6. me presenting a
poster @
ISWC2019
poster session
ISWC2019
poster
session
ISWC
2019
ISWC
me presenting a
poster @
ISWC2019
poster session
ISWC2019
poster
session
ISWC
2019
ISWC
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7. Looking around
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8. Competency Questions
ID COMPETENCY QUESTION
CQ1 Which are the events of a recurrent event series?
CQ2 Which is the time period elapsing between two events of a recurrent event
series?
CQ3 What are the unifying criteria shared by all the events in a
recurrent event series?
CQ4 Which is the (immediate) next event in a recurrent event series?
CQ5 Which is the (immediate) previous event in a recurrent event series?
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9. RecurrentEventSeries ODP
ontologydesignpatterns.org/wiki/Submissions:RecurrentEventSeries
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10. :RecurrentEventSeries
Recurrent event series as an
intersection of Collection and Situation
its members are of type Event
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11. :hasNextEvent, :hasPreviousEvent
The member events are
in sequence
These properties relate only events
member of the same recurrent event series
example for :hasNextEvent
if not, running queries
like this generates triples
asserting local
inconsistencies
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12. :isTheLastEvent
:eventNumber
Is this event the last event of the series, or not?
Which position this event has in the series?
1, 2, 3, …
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13. :UnifyingFactor
at least one element
or property
occurs in each event member
with some degree of flexibility
topic
e.g.
place
organizer … 12

14. :TimePeriod
It represents the recurrence of a Recurrent Event Series
approximated temporal distance
between one member event and the next and the previous ones
Estimated or Observed time
period?
future work
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It works as a parameter region of valid values

15. e.g.
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possible implementation

16. Example
[…]
Umbria Jazz has been held annually, since 1973,
and has:
• the musical genre jazz as topic
• Umbria as event place
• July as month in which it usually* takes place
• a time period of ~1 year between two
consecutive occurrences
* always since 1976
1974 and 1975 started in July and ended on August 1st
1973 was held in August 15

17. 16

18. Future work
- Traditional ceremonies, festivals, cultural events, but also:
• sunrise
• periodic migrations of animals
• world days
• train schedule
• medical prescriptions
• periodical supply of services
natural origin
set by humans
part of a workflow
- Recurrent Event as a fluent?
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19. Thank you!
Valentina Anita Carriero
valentina.carriero@istc.cnr.it