Temporal Reasoning: the LaTeR project (LAyered TEmporal Reasoning)
SCIENTIFIC CONTEXT:
- Artificial Intelligence,
- Constraint Satisfaction Problems
- Temporal Reasoning
- Temporal Databases
COOPERATIONS
- Politecnico di Milano, Dip. di Elettronica on Temporal
databases
MAIN GOALS:
- Analysis of the computational complexity of temporal reasoning
- Development of an efficient temporal reasoner
- Loosely coupled approach to temporal reasoning:
temporal reasoner as an agent that can cooperate with
other systems (problem solvers)
- Use of the temporal reasoner in other tasks
- Diagnosis (see MBD project)
- Extension of relational databases to deal with different types of temporal information
METHODOLOGY:
- Use of constraint frameworks based on linear inequalities
(specifically ˆbounds on differences‰)
- Analysis of complexity results for such constraint
frameworks
- New approach for the complexity of querying such
constraint frameworks and checking whether new
constraints are consistent with existing ones
- Development of a general purpose temporal reasoner;
- Two-layered architecture
- low level based on constraint framework
- high level interface language
- Loosely coupled integration of the temporal reasoner with
other problem solving tasks
MAIN RESULTS
- New complexity results for a class of constraint frameworks
based on linear inequalities
- Development of a system for efficient temporal reasoning
- high level interface language (manipulation and
query)
- efficient query processing (complexity independent
of the dimension of the knowledge base)
- Extension of the relational database model to deal with time
- time referent associated with each tuple
- various type of temporal information on tuples
(temporal location, duration, delays, qualitative relations)
- temporal relational algebra
- A new approach temporal model-based diagnosis
(see MBD project)
PROTOTYPES AND SYSTEMS:
APPLICATIONS
RELATIONS WITH OTHER PROJECTS
REFERENCES
- V. Brusoni, L. Console, P. Terenziani: On the computational
complexity of querying bounds on differences constraints,
Artificial Intelligence, vol. 74, no. 2, pp. 367-379, 1995
- V. Brusoni, L. Console, B. Pernici, P. Terenziani: LaTeR, a
general purpose manager of temporal information, LNCS 869
Springer Verlag 1994
- V. Brusoni, L. Console, B. Pernici, P. Terenziani:
Extending Temporal Relational Databases
to Deal with Imprecise and Qualitative Temporal Information;
Proc. International Workshop on temporal databases,
Zurich, September 1995.
- L. Console, B. Pernici, P. Terenziani: A general temporal
manager for temporal databases, Proc. Int. Works on an
infrastructure for temporal databases, (R. Snodgrass ed.), 1993