Geen diatitel

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CURRENT RESEARCH INFORMATION SYSTEMS
TECHNOLOGIES
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Introduction

• Who am I?
• Geert Van Grootel
• Senior researcher Science division, Ministry of
  the Flemish community.
• IWETO Flemish CRIS
• CERIF taskgroup member
• euroCRIS treasurer.

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Structure of presentation

• Introduction Terminology
• Past present technologies
• Examples of implementations
• CERIF Technology

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Context Integration of CRISs

• Different organisational levels geography
• a scientific discipline
• intra institutional
• between institutions
• Different levels of government
• regional, national, international, global.
• Different levels of system integration
• integrated system (ERP)
• intra process data capture collection
• extra process

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CRIS

• Current research Information System
• Technologies behind CRISs
• Document stores
• Relational Database Managment Systems (RDBMS)
• Object Oriented Database Managment Systems
  (OODBMS)
• Information Retrieval systems (IR)

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Document stores

• Document systems
• Based on Markup Languages (SGML, XML)
• in extistance since the 80s
• Rise in popularity with XML behind it as semi
  structured database.
• Querying is usually poor
• query language is procedural and navigational as
  opposed to declarative predicates
• Difficult to maintain
• updating is slow when changes effect several
  entity instances but fast when only with one
  document.
• Variable report capabilities group, sum,
  average,...

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Information Retrieval Systems

• Advantages for databases with many textual
  attributes
• via Full inverted index
• very fast retrieval
• very slow update
• little or no structural capability ( relations
  between entities)
• little or no reporting capability
• group, sum, average,...

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OODBMS

• Crucial to OODBMS is the concept of objects
• Data (structure view)
• Methods (process view)
• Messages (event view)
• Any process has to be codes specifically for any
  object
• solutions is inheritence to help reduce coding
  efforts
• Disadvantages
• performance, worse than RDBMS
• poorer data representational capabilities

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RDBMS

• Pros
• Mathematically formal
• easy to understand
• standard query language (SQL)
• mature technology

• Cons
• hard to represent complex objects
• High performance needs expert knowledge

Flexible linking relations between business
objects
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Technology for CRISs

• Essential Building blocks
• Metadata
• Dictionaries, Thesauri Ontologies
• Keys Binary Relations

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Data Metadata

• Incredible amount of data but much of this data
  is unaccesible
• What we need
• Find relevant data as information
• Understand it syntax, semantics
• Understand any restrictions on its use
• The key to this is METADATA

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Metadata

• Importance
• Integrity control
• Access control
• Support of data
• Classification, valid terms
• Interoperability
• Data exchange
• Data access

• Benefits
• Data quality
• Access
• Understanding answers
• Improving queries
• Interoperability
• other CRISs
• other Systems
• MIS, RMS
• Bibliographic systems
• Scientific data

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Three Kinds of Metadata
view to users
SCHEMA
NAVIGATIONAL
ASSOCIATIVE
constrain it
how to get it
data (document)
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SCHEMA METADATA
view to users
SCHEMA
NAVIGATIONAL
ASSOCIATIVE
constrain it
how to get it
data (document)
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Metadata Kinds Schema

• intensional description of extensional instances
• database
• name
• size
• security authorisations
• attributes
• name
• type
• constraints
• formal logic relationship to data instances

SCHEMA
constrain it
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ASSOCIATIVE METADATA
view to users
SCHEMA
NAVIGATIONAL
ASSOCIATIVE
constrain it
how to get it
data (document)
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Associative Metadata
view to users

• information for application assistance
• catalog record (e.g. Dublin Core) - descriptive
• content rating (e.g. PICS) -
  restrictive
• security, privacy (cryptography, digital
  signatures) - restrictive
• information from dictionaries, thesauri,
  hyperglossaries, domain ontologies
  - supportive
• no formal logic relationship to data instances

ASSOCIATIVE
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NAVIGATIONAL METADATA
view to users
SCHEMA
NAVIGATIONAL
ASSOCIATIVE
constrain it
how to get it
data (document)
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NAVIGATIONAL METADATA

• How to get to information resource direct
• filename
• DB name navigational algorithm
• DB name predicate (query)
• URL
• URL predicate (query)
• or any of the above via
• web indexing system (eg AltaVista, ExCite)
• local indexing system bookmarks or proxy server)

NAVIGATIONAL
how to get it
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Metadata
Collecting observed facts
DATA
Structuring in Context
INFORMATION
Inducing commonly accepted belief
KNOWLEDGE
INSIGHT
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Technology for CRISs

• Essential Building blocks
• Metadata
• Dictionaries, Thesauri Ontologies
• Keys Binary Relations

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ONTOLOGY

• What is an Ontology
• A specification of a conceptualization.
• A formal description of the concepts and
  relationships that can exist for an agent or a
  community of agents
• The knowledge of a domain defined in a formal
  declarative language
• The collection of semantic definitions for a
  domain.
• In practice a resource of terms, their
  definitions and their logical inter-relationships.
  

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DOMAIN ONTOLOGY

• Domain Ontology
• An ontology covering a specific subject area of
  interest (a domain).
• The set of objects that can represented can be
  called the universe of discourse.
• E.g. For a project to exist it must have a
  startdate, a subject, a goal, a promotor and a
  budget
• Project lt- startdate AND subject AND goal AND
  promotor AND budget gt 0

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DOMAIN ONTOLOGY

• Domain Ontologies in IT
• A representation in first order logic allowing
• Facts to be expressed
• Relationships to be expressed
• Constraints to be expressed
• New facts and relationships to be deduced or
  induced

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And so.

• Metadata is the key to
• GRIDs
• SEMANTIC WEB