Towards Ideal Semantics for Analyzing Stream Reasoning Harald Beck - - PowerPoint PPT Presentation
Towards Ideal Semantics for Analyzing Stream Reasoning Harald Beck - - PowerPoint PPT Presentation
Towards Ideal Semantics for Analyzing Stream Reasoning Harald Beck Minh Dao-Tran Thomas Eiter Michael Fink International Workshop on Reactive Concepts in Knowledge Representation 2014 August 19, 2014 Scope & Motivation Windows &
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
◮ Semantics
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
◮ Semantics: Lack of theory
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
◮ Semantics: Lack of theory ◮ Analysis
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
◮ Semantics: Lack of theory ◮ Analysis: Hard to predict, hard to compare
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
◮ Semantics: Lack of theory ◮ Analysis: Hard to predict, hard to compare ◮ Ideal
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
What & Why
“Towards Ideal Semantics for Analyzing Stream Reasoning”
◮ Stream Reasoning: Logical reasoning on streaming data
◮ Streams = tuples (atoms) with timestamps ◮ Essential aspect: window functions
◮ Semantics: Lack of theory ◮ Analysis: Hard to predict, hard to compare ◮ Ideal
◮ Idealization: Abstract from practical (operational) issues ◮ Generalization: Uniform representation
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 1 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) 2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) 2 8
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) 2 8
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) 2 8 11
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
Answer: i1, i2, p1
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
Answer: i1, i2, p1 and i3, i4, p2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
Answer: i1, i2, p1 and i3, i4, p2
◮ SQL
SELECT * FROM tram, bus WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
Answer: i1, i2, p1 and i3, i4, p2
◮ SQL
SELECT * FROM tram, bus WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
Answer: i1, i2, p1 and i3, i4, p2
◮ SQL
SELECT * FROM tram, bus WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2)
◮ Normal DB: Query for trams and buses arriving at same station P
Answer: i1, i2, p1 and i3, i4, p2
◮ SQL
SELECT * FROM tram, bus WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream setting, at time 13: Query for
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream setting, at time 13: Query for ◮ Trams and buses arriving at same station P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream setting, at time 13: Query for ◮ Trams and buses arriving at same station P within the last 5 min
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream setting, at time 13: Query for ◮ Trams and buses arriving at same station P within the last 5 min
Answer: i3, i4, p2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream setting, at time 13: Query for ◮ Trams and buses arriving at same station P within the last 5 min
Answer: i3, i4, p2
◮ CQL
SELECT * FROM tram [RANGE 5], bus [RANGE 5] WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Trams and buses arriving at same station P within the last 5 min
at the same time
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Trams and buses arriving at same station P within the last 5 min
at the same time Answer: –
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13 3 4 5 6 7
◮ Trams and buses arriving at same station P within the last 5 min
at the same time Answer: i1, i2, p1 for query times 2, . . . , 7
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Trams and buses arriving at same station P within the last 5 min
at the same time Answer: i1, i2, p1 for query times 2, . . . , 7
◮ CQL: Not expressible in single query (Snapshot semantics)
SELECT * AS tram bus FROM tram [NOW], bus [NOW] WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) 2 8 11 13
◮ Trams and buses arriving at same station P within the last 5 min
at the same time Answer: i1, i2, p1 for query times 2, . . . , 7
◮ CQL: Not expressible in single query (Snapshot semantics)
SELECT * AS tram bus FROM tram [NOW], bus [NOW] WHERE tram.P = bus.P
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) 2 8 11 13
◮ Trams and buses arriving at same station P within the last 5 min
at the same time Answer: i1, i2, p1 for query times 2, . . . , 7
◮ CQL: Not expressible in single query (Snapshot semantics)
SELECT * AS tram bus FROM tram [NOW], bus [NOW] WHERE tram.P = bus.P SELECT * FROM tram bus [RANGE 5]
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Trams and buses
Arrival times at different stations pi
tram(i1, p1) bus(i2, p1) 2 8 11 13
◮ Trams and buses arriving at same station P within the last 5 min
at the same time Answer: i1, i2, p1 for query times 2, . . . , 7
◮ CQL: Not expressible in single query (Snapshot semantics)
SELECT * AS tram bus FROM tram [NOW], bus [NOW] WHERE tram.P = bus.P SELECT * FROM tram bus [RANGE 5]
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 2 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Window Types
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Time-based
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 3 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Window Types
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Time-based ◮ Tuple-based
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 3 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Window Types
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Time-based ◮ Tuple-based
◮ Not necessarily unique. E.g.: Last 3 tuples
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 3 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Window Types
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Time-based ◮ Tuple-based
◮ Not necessarily unique. E.g.: Last 3 tuples
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 3 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Window Types
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Time-based ◮ Tuple-based
◮ Not necessarily unique. E.g.: Last 3 tuples
◮ Partition-based
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 3 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Window Types
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Time-based ◮ Tuple-based
◮ Not necessarily unique. E.g.: Last 3 tuples
◮ Partition-based
◮ Apply tuple-based window on substreams
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 3 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?”
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?”
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?” ◮ Allow for nesting: windows within windows
◮ As formal counterpart to repeated runs of continuous queries
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?” ◮ Allow for nesting: windows within windows
◮ As formal counterpart to repeated runs of continuous queries
◮ Allow for looking into the future
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?” ◮ Allow for nesting: windows within windows
◮ As formal counterpart to repeated runs of continuous queries
◮ Allow for looking into the future ◮ View window operators as first class citizens
◮ Do not separate window application (first) from logic (then)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?” ◮ Allow for nesting: windows within windows
◮ As formal counterpart to repeated runs of continuous queries
◮ Allow for looking into the future ◮ View window operators as first class citizens
◮ Do not separate window application (first) from logic (then)
◮ Leave open specific underlying window functions
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Windows
◮ Example: “In the last hour, did a bus always arrive within 5 min?” ◮ Allow for nesting: windows within windows
◮ As formal counterpart to repeated runs of continuous queries
◮ Allow for looking into the future ◮ View window operators as first class citizens
◮ Do not separate window application (first) from logic (then)
◮ Leave open specific underlying window functions
◮ w(S, t) → S′ ◮ Stream S, time point t ∈ N, new stream S′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 4 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 1 2 3 4 5 6
a a a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. 1 2 3 4 5 6
a a a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′? ♦ a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′? ♦ a yes
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′? ♦ a yes . . . at all time points t′?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′? ♦ a yes . . . at all time points t′? a
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′? ♦ a yes . . . at all time points t′? a no
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Ideas for Time Reference
◮ Atoms a appearing in the stream at time points 1, 2, 5 ◮ Query time t = 4. Window on interval [1, 4] 1 2 3 4 5 6
a a a
- ◮ Example queries: In this window, does a hold. . .
. . . now, i.e., exactly at t? a no . . . at time point 2? @2 a yes . . . at some time point t′? ♦ a yes . . . at all time points t′? a no
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 5 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream S = (T, υ), where
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream S = (T, υ), where
◮ T: interval in N
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
◮ Example
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
◮ Example
◮ T = [0, 13]
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 8 11 13 2
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
◮ Example
◮ T = [0, 13] ◮ υ =
2 → {tram(i1, p1), bus(i2, p1)}
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 11 13 8
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
◮ Example
◮ T = [0, 13] ◮ υ =
2 → {tram(i1, p1), bus(i2, p1)}, 8 → {tram(i3, p2)}
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 13 11
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
◮ Example
◮ T = [0, 13] ◮ υ =
2 → {tram(i1, p1), bus(i2, p1)}, 8 → {tram(i3, p2)}, 11 → {bus(i4, p2)}
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Streams
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
◮ Stream S = (T, υ), where
◮ T: interval in N ◮ υ : T → 2G (interpretation of ground atoms G)
◮ Example
◮ T = [0, 13] ◮ υ =
2 → {tram(i1, p1), bus(i2, p1)}, 8 → {tram(i3, p2)}, 11 → {bus(i4, p2)}, i → ∅ else
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 6 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::=
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α | ♦α | α | @tα
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α | ♦α | α | @tα | ⊞iα
◮ ⊞i window operator: change view on stream
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α | ♦α | α | @tα | ⊞iα
◮ ⊞i window operator: change view on stream
◮ Utilizing window function with identifier i
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α | ♦α | α | @tα | ⊞iα
◮ ⊞i window operator: change view on stream
◮ Utilizing window function with identifier i ◮ Change considered substream based on current time point, and ◮ current window, or ◮ original stream
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α | ♦α | α | @tα | ⊞iα
◮ ⊞i window operator: change view on stream
◮ Utilizing window function with identifier i ◮ Change considered substream based on current time point, and ◮ current window, or ◮ original stream ◮ Window operator = window function + stream choice function
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Formulas
◮ Formulas defined by the grammar (atom a, t ∈ N timepoint)
α ::= a | ¬α | α ∧ α | α ∨ α | α → α | ♦α | α | @tα | ⊞iα
◮ ⊞i window operator: change view on stream
◮ Utilizing window function with identifier i ◮ Change considered substream based on current time point, and ◮ current window, or ◮ original stream ◮ Window operator = window function + stream choice function ◮ Why keep the original stream?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 7 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram bus tram bus 2 8 11 13
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram bus tram bus 2 8 11 13
◮ Partition-based window
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram bus tram bus 2 8 11 13
◮ Partition-based window
◮ Partition stream into substreams: trams vs. buses
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram tram 2 8 13
◮ Partition-based window
◮ Partition stream into substreams: trams vs. buses ◮ Apply tuple-based windows on substreams: 2 trams, 0 buses
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram tram 2 8 13
◮ Partition-based window
◮ Partition stream into substreams: trams vs. buses ◮ Apply tuple-based windows on substreams: 2 trams, 0 buses
◮ In the new view, buses are invisible
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram tram 2 8 7 13
◮ Partition-based window
◮ Partition stream into substreams: trams vs. buses ◮ Apply tuple-based windows on substreams: 2 trams, 0 buses
◮ In the new view, buses are invisible ◮ ⇒ For “within 5 min” window: use data of original stream again
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Nested Windows and Stream Choice
◮ “For the last two trams, did a bus always appear within 5 min?”
tram bus tram bus 2 8 7 13 11
◮ Partition-based window
◮ Partition stream into substreams: trams vs. buses ◮ Apply tuple-based windows on substreams: 2 trams, 0 buses
◮ In the new view, buses are invisible ◮ ⇒ For “within 5 min” window: use data of original stream again
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 8 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream ◮ ˆ
W mapping from idenfiers (in N) to extended window functions
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream ◮ ˆ
W mapping from idenfiers (in N) to extended window functions
◮ choice function ch(S1, S2) → S′
ˆ w(S1, S2, t) = w(ch(S1, S2), t)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream ◮ ˆ
W mapping from idenfiers (in N) to extended window functions
◮ choice function ch(S1, S2) → S′
ˆ w(S1, S2, t) = w(ch(S1, S2), t)
◮ Example
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream ◮ ˆ
W mapping from idenfiers (in N) to extended window functions
◮ choice function ch(S1, S2) → S′
ˆ w(S1, S2, t) = w(ch(S1, S2), t)
◮ Example
◮ w5 time-based window for last 5 minutes
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream ◮ ˆ
W mapping from idenfiers (in N) to extended window functions
◮ choice function ch(S1, S2) → S′
ˆ w(S1, S2, t) = w(ch(S1, S2), t)
◮ Example
◮ w5 time-based window for last 5 minutes ◮ ch2 choice that selects the second stream (ch2(S1, S2) = S2)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Structure
◮ Structure M = T, υ, ˆ
W, where
◮ (T, υ) original stream ◮ ˆ
W mapping from idenfiers (in N) to extended window functions
◮ choice function ch(S1, S2) → S′
ˆ w(S1, S2, t) = w(ch(S1, S2), t)
◮ Example
◮ w5 time-based window for last 5 minutes ◮ ch2 choice that selects the second stream (ch2(S1, S2) = S2) ◮ ˆ
W(1) = ˆ w5, where ˆ w5(S1, S2, t) = w5(S2, t)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 9 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
M, S, t a iff a ∈ υS(t) ,
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
M, S, t a iff a ∈ υS(t) , M, S, t ¬α iff M, S, t α, M, S, t α ∧ β iff M, S, t α and M, S, t β, M, S, t α ∨ β iff M, S, t α or M, S, t β, M, S, t α → β iff M, S, t α or M, S, t β,
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
M, S, t a iff a ∈ υS(t) , M, S, t ¬α iff M, S, t α, M, S, t α ∧ β iff M, S, t α and M, S, t β, M, S, t α ∨ β iff M, S, t α or M, S, t β, M, S, t α → β iff M, S, t α or M, S, t β, M, S, t ♦α iff M, S, t′ α for some t′ ∈ TS,
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
M, S, t a iff a ∈ υS(t) , M, S, t ¬α iff M, S, t α, M, S, t α ∧ β iff M, S, t α and M, S, t β, M, S, t α ∨ β iff M, S, t α or M, S, t β, M, S, t α → β iff M, S, t α or M, S, t β, M, S, t ♦α iff M, S, t′ α for some t′ ∈ TS, M, S, t α iff M, S, t′ α for all t′ ∈ TS ,
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
M, S, t a iff a ∈ υS(t) , M, S, t ¬α iff M, S, t α, M, S, t α ∧ β iff M, S, t α and M, S, t β, M, S, t α ∨ β iff M, S, t α or M, S, t β, M, S, t α → β iff M, S, t α or M, S, t β, M, S, t ♦α iff M, S, t′ α for some t′ ∈ TS, M, S, t α iff M, S, t′ α for all t′ ∈ TS , M, S, t @t′α iff M, S, t′ α and t′ ∈ TS ,
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Semantics: Entailment
◮ Structure M = T, υ, ˆ
W with original stream SM = (T, υ)
◮ Substream S = (TS, υS) of SM: currently considered window ◮ Time point t ∈ TS (query time) ◮ Entailment between M, S, t and formulas α, β
M, S, t a iff a ∈ υS(t) , M, S, t ¬α iff M, S, t α, M, S, t α ∧ β iff M, S, t α and M, S, t β, M, S, t α ∨ β iff M, S, t α or M, S, t β, M, S, t α → β iff M, S, t α or M, S, t β, M, S, t ♦α iff M, S, t′ α for some t′ ∈ TS, M, S, t α iff M, S, t′ α for all t′ ∈ TS , M, S, t @t′α iff M, S, t′ α and t′ ∈ TS , M, S, t ⊞iα iff M, S′, t α where S′ = ˆ wi(SM, S, t).
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 10 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 bus(i2, p1)?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
tram(i1, p1) tram(i3, p2) bus(i4, p2) bus(i2, p1) 2 8 11 13
M, SM, 13 bus(i2, p1), since bus(i2, p1) ∈ υ(13)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 ♦bus(i2, p1)?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
tram(i1, p1) tram(i3, p2) bus(i4, p2) bus(i2, p1) 8 11 13 2
M, SM, 13 ♦bus(i2, p1), since ∃ t′ ∈ TSM s.t. bus(i2, p1) ∈ υ(t′)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
⊞1: last 5 min
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 ⊞1♦ bus(i2, p1)?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
⊞1: last 5 min
tram(i1, p1) tram(i3, p2) bus(i4, p2) bus(i2, p1) 13 2 8 9 10 11 12 13
M, SM, 13 ⊞1♦ bus(i2, p1)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Queries
◮ Query α[t]: “M, SM, t α”?
⊞1: last 5 min
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13 9 10 12
M, SM, 13 ⊞1♦ bus(i4, p2)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 11 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 ⊞1♦bus(X, P)?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 ⊞1♦bus(X, P)? X → i4, P → p2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, S, U ⊞1♦bus(i2, p1)?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) tram(i3, p2) bus(i4, p2) bus(i2, p1) 8 11 13 2 3 4 5 6 7
M, S, U ⊞1♦bus(i2, p1)? U → 2, . . . , 7
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 9 10 11 12 13
M, SM, 13 ⊞1(♦tram(X, P) ∧ ♦bus(Y, P))?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 ⊞1(♦tram(X, P) ∧ ♦bus(Y, P))? X → i3, P → p2, Y → i4
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, U ⊞1♦(tram(X, P) ∧ bus(Y, P))?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i3, p2) bus(i4, p2) tram(i1, p1) bus(i2, p1) 8 11 13 2 3 4 5 6 7
M, SM, U ⊞1♦(tram(X, P) ∧ bus(Y, P))? U → 2, . . . , 7 × X → i1, P → p1, Y → i2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i1, p1) bus(i2, p1) tram(i3, p2) bus(i4, p2) 2 8 11 13
M, SM, 13 @U(tram(X, P)) ∧ bus(Y, P))?
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Non-ground Queries
◮ Non-ground query: Assignments s.t. substitution hold
tram(i3, p2) bus(i4, p2) tram(i1, p1) bus(i2, p1) 8 11 13 2
M, SM, 13 @U(tram(X, P)) ∧ bus(Y, P))? U → 2, X → i1, P → p1, Y → i2
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 12 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
◮ ⊞i: time-based window for last i minutes
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60 ⊞5
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60 ⊞5 ♦
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus bus bus 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60 ⊞5 ♦ bus
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus(i, p) bus(j, q) bus(k, r) 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60 ⊞5 ♦ bus ◮ Limitation: ⊞60 ⊞5 ♦ bus(X, P)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Example: Nested Window
◮ “In the last hour, did a bus always appear in the last 5 minutes?”
bus(i, p) bus(j, q) bus(k, r) 206 213 217 t
◮ ⊞i: time-based window for last i minutes ◮ Query: ⊞60 ⊞5 ♦ bus ◮ Limitation: ⊞60 ⊞5 ♦ bus(X, P)
◮ Result: List of fixed combinations X, P ◮ Need a rule: some bus ← bus(X, P) ◮ Then: ⊞60 ⊞5 ♦some bus
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 13 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
t − k
◮ Past
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? t − k
◮ Past: Lack of theoretical underpinning for stream reasoning
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? t − k t (now)
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) t − k t (now)
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) t − k t (now) t + ε
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) b ← a t − k t (now) t + ε
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon: Rule-based extension (OrdRing @ ISWC, Oct.’14)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) b ← a t − k t (now) t + ε t + n
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon: Rule-based extension (OrdRing @ ISWC, Oct.’14) ◮ Later
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) b ← a CQL, ETALIS properties t − k t (now) t + ε t + n
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon: Rule-based extension (OrdRing @ ISWC, Oct.’14) ◮ Later: Language properties, capture CQL and ETALIS
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) b ← a CQL, ETALIS properties t − k t (now) t + ε t + n t + n + m
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon: Rule-based extension (OrdRing @ ISWC, Oct.’14) ◮ Later: Language properties, capture CQL and ETALIS ◮ Eventually
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) b ← a CQL, ETALIS properties distributed t − k t (now) t + ε t + n t + n + m
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon: Rule-based extension (OrdRing @ ISWC, Oct.’14) ◮ Later: Language properties, capture CQL and ETALIS ◮ Eventually: Distributed setting, heterogeneous nodes
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
Conclusion Stream
? | = ? ⊞(a ∧ ♦b) b ← a CQL, ETALIS properties distributed t − k t (now) t + ε t + n t + n + m
◮ Past: Lack of theoretical underpinning for stream reasoning ◮ Now: First language for modelling semantics precisely
◮ flexible window operator (first class citizen) ◮ time reference / time abstraction
◮ Soon: Rule-based extension (OrdRing @ ISWC, Oct.’14) ◮ Later: Language properties, capture CQL and ETALIS ◮ Eventually: Distributed setting, heterogeneous nodes
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 14 / 15
Scope & Motivation Windows & Time Framework Examples Conclusion & Outlook
To je ono.
(That’s it.)
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 15 / 15
Appendix
Time-based window
◮ Example
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- d
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- ×
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- ×
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- ×
ℓ
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- ×
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- × u
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example: Query time t = 4
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- ×
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15
Appendix
Time-based window
◮ Example
ℓ 2 time points into the past u 1 time points into the future d 3 step size (slide parameter)
1 2 3 4 5 6 7 8 9
- ×
× × ×
- ×
× ×
- ×
× ×
- : query times t
×: pivot points t′
- H. Beck (TU Vienna)
Towards Ideal Semantics for Analyzing Stream Reasoning ReactKnow’14 16 / 15