Architecture for Pattern- Base Management Systems Manolis TerrovitisPanos Vassiliadis National Technical Univ. of Athens, Dept. of Electrical and Computer Eng., Athens, Hellas University of Ioannina, Dept. of Computer Science, Ioannina, Hellas

2 Outline Introduction and Motivation “Manifesto”-User requirements PBMS architecture

3 Outline Introduction and Motivation “Manifesto”-User requirements PBMS architecture

4 The Problem Vast amounts of raw data. Data mining is not enough to extract knowledge. The core of the problem: –Keeping, Storing and Manipulating knowledge from raw data.

5 Knowledge as Patterns “Patterns are compact and rich in semantics representations of raw data “

6 The need for a new PBMS Current DBMS’s cannot address the new user requirements patterns impose. We need a system to provide powerful and specialized manipulation abilities for patterns. We need a Pattern Base Management System.

7 Main topics A “manifesto”-like list of requirements for a PBMS. A reference architecture for a PBMS. Discussion of the differences between ORDBMS’s and PBMS.

8 Outline Introduction and Motivation “Manifesto”-User requirements PBMS architecture

9 Requirements for the PBMS User requirements for the Data Model. User requirements for the PBMS architecture. User requirements for the query language and processing.

10 Requirements for the Data Model Compact and Rich in semantics. Based upon a generic uniform model that covers all kinds of patterns. Support different types of patterns in an extensible fashion. Allow semantically similar patterns to be identified. Support composite patterns, generated from simpler ones.

11 Requirements for the Architecture Mechanisms for representing and storing its entries. Cooperation with DBMS’s storing raw data. Ability to manage pattern extraction and creation. Access to intermediate results of pattern creation algorithms.

12 Requirements for Query language and Processing A PBMS processes different kinds of queries, possibly even on raw data and returns more intuitive results to users. A PBMS employs a query language which can at least perform the following tasks: –Pattern matching –Logical inferences –Meta queries

13 Outline Introduction and Motivation “Manifesto”-User requirements PBMS architecture

14 PBMS Architecture PBMS –Pattern Layer –Pattern Type Layer –Class Layer Intermediate Results RDBMS –Raw data

15 Pattern Type Layer Pattern types: describe the syntax of the patterns. –Structure –Declarative specification Patterns are instantiations of Pattern Types, which follow the structure of the types. Pattern Type layer is extensible.

16 Class Layer Classes: collections of patterns which share some semantic property. Patterns of a certain class must all be instances of the same type. Classes are used to create patterns with predefined semantics given by the designer. Classes are defined over features.

17 Is it really different from an OO/ORDBMS? Semantically rich representation of patterns. Novel querying requirements: –Ad hoc operations over the source and pattern spaces and their mapping –Pattern matching –Reasoning facilities based on the declarative specification of patterns Alternative storage, indexing and query optimization techniques.

18 Summary A “manifesto”-like list of requirements for a PBMS A reference architecture for a PBMS Discussion of the differences between ORDBMS’s and PBMS