1. Representing and Transforming Model-Based Information
Shawn Bowers and Lois Delcambre
Department of Computer Science and Engineering
Oregon Graduate Institute
Copyright © 2000

2. Model-Based Information and Tools
Painting
Painter
by painter
Influenced by
mentioned
biography
critiqued
XML Viewer
SQL
TM Browser
XML DB
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3. Our Goals Represent information generically, for various models
Convert information from one representation scheme to another
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4. Transforming Information
XML DB
XML Viewer
SQL
TM Browser
Painting
Painter
by painter
Influenced by
mentioned
biography
critiqued
Generic Rep.
(XML model)
convert
(Topic Map model)
convert
Generic Rep.
(Relational model)
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5. Our Approach Metamodel Generic Representation Scheme Mapping Formalism
to represent multiple data models
Generic Representation Scheme
to store model, schema, and instances for model-based information
Mapping Formalism
to transform between representation schemes
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6. The Metamodel Provides a level of abstraction above models
Describes the structural features of models
Basic Set of Abstractions
Metamodel
Model Constructs and Relationships
Topic Map
XML
Topic Map Defintions
DTD
Schema-Level
Data
Topic Map
Instances
XML Document
Instance-Level
Data
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7. XML Model, Schema, and Instance
Model constructs and relationships defined using the metamodel
Elements, Element Types, Attributes, Attribute Types
Elements contain Attributes
Elements can be nested
XML
Model
<!ELEMENT schedule (flight*)>
<!ELEMENT flight (from, to, price)>
<!ATTLIST flight name CDATA #REQUIRED>
XML DTD
(Schema)
<schedule>
<flight name=“Air Canada Flight 1575”>
<from> PDX </from>
<to> YVR </to>
<price> $ </price>
</flight>
...
</schedule>
XML Document
(Instances)
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8. Topic Map Example Influenced by by painter Painting Painter by painter
critiqued
mentioned
mentioned
biography
by painter
influenced by
critiqued
“Captive”
“Paul Klee”
biography
biography
“Francisco de Goya”
mentioned
mentioned
“1914”
by painter
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9. Topic Map Model in UML TopicType TopicInstance ttypename : String
<<conformance>>
topic_instOf
TopicType
TopicInstance 1 1 * 1
ttypename : String
title : String
topicInsID : Number 1 1
topic
Type1
topic
Type2 1 1
topicType
topic
Ins1
topic
Ins2 * *
topicIns
TopicRelType
<<conformance>>
rel_instOf * * 1 *
relType : String
TopicRelInst
<<conformance>>
anchor_instOf
AnchorType
AnchorInst * 1 * *
anchorRole : String *
address 1
<<Mark>>
Address
markID : String
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10. Generic Representation
We use RDF and RDF Schema to represent model, schema, and instance uniformly
RDF Graph
RDF Triples
creator
name
(creator, ‘ person1)
(name, ‘person1’, ‘John Smith’)
person1
‘John Smith’
RDF Schema Graph
RDF Schema Triples
Property
(type, ‘creator’, Property)
(domain, ‘creator’, WebPage)
(range, ‘creator’, Person)
(type, ‘Person’, Class)
(type, ‘WebPage’, Class)
WebPage
type
Class
domain
type
type
creator
Person
range
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11. <<conformance>>
Representing Models
(instanceOf, “TopicType”, Construct)
(instanceOf, “TopicInstance”, Construct)
(instanceOf, “topic_instOf”, Conformance)
(domain, “topic_instOf”, TopicInstance)
(range, “topic_instOf”, TopicType)
(domainMult, “topic_instOf”, “*”)
(rangeMult, “topic_instOf”, “1”)
(instanceOf, “ttypename”, Connector)
(domain, “ttypename”, TopicType)
(range, “ttypename”, String)
(domainMult, “ttypename”, “*”)
(rangeMult, “ttypename”, “1”)
TopicType
ttypename : String 1
<<conformance>>
topic_instOf *
TopicInstance
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12. Representing Schema Topic Types (schema):
(instanceOf, “painting_tt”, TopicType)
(ttypename, “painting_tt”, “painting”)
(instanceOf, “painter_tt”, TopicType)
(ttypename, “painter_tt”, “painter”)
(instanceOf, “byPainter_rt”, TopicRelType)
(relType, “byPainter_rt”, “by painter”)
(topicType1, “byPainter_rt”, painting_tt)
(topicType2, “byPainter_rt”, painter_tt)
(instanceOf, “biography_at”, AnchorType)
(anchorRole, “biography_at”, “biography”)
(topicType, “biography_at”, painter_tt)
Topic Types (schema):
painting, painter
Topic Rel Types (schema):
by painter
Anchor Types (schema):
biography
by painter
painting
painter
biography
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13. Representing Instances
(instanceOf, “painter1”, TopicInstance)
(title, “painter1”, “Paul Klee”)
(topicInsID, “painter1”, “5”)
(topic_instOf, “painter1”, painter_tt)
(instanceOf, “painting1”, TopicInstance)
(title, “painting1”, “Captive”)
(topicInsID, “painting1”, “19”)
(topic_instOf, “painting1”, painting_tt)
(instanceOf, “byPainter1”, TopicRelInst)
(rel_instOf, “byPainter1”, byPainter_rt)
(topicIns1, “byPainter1”, painting1)
(topicIns2, “byPainter1”, painter1)
(instanceOf, “biography1”, AnchorInst)
(anchor_instOf, “biography1”, biography_at)
(address, “biography1”, a1)
(instanceOf, “a1”, Address)
(markID, “a1”,
Topic (instances):
Paul Klee, Captive
Topic Relationship (instance):
a by painter relationship
Anchor (instance):
a biography anchor
Address (instance):
mark to URL
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14. Basic Types of Mappings
Mapped
Model1
Model2
Converted
Inter-Model
Schema1
Schema1
Converted
Instances1
Instances1
Model1
Model1
Inter-Schema
Mapped
Schema1
Schema2
Converted
Instances1
Instances1
Model1
Mapped
Model2
Model-to-Schema
Schema1
Converted
Schema2
Instances1
Converted
Instances2
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15. Mapping Rules Simple production rules over triples Mapped
TopicInstance
XMLElem
S(‘source’, (‘instanceOf’, X, ‘TopicInstance’)) 
S(‘target’, (‘instanceOf’, X, ‘XMLElem’))
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16. Mapping Rules (cont.) TopicInstance XMLElem Mapped topic_instOf
elem_instOf
TopicType
XMLElemType
S(‘source’, (‘topic_instOf’, X, Y))
S(‘target’, (‘instanceOf’, X, ‘XMLElem’))
S(‘target’, (‘instanceOf’, Y, ‘XMLElemType’)) 
S(‘target’, (‘elem_instOf’, X, Y))
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17. Conclusion Metamodel A Generic Representation Scheme Mapping Formalism
to describe multiple (superimposed) data models
A Generic Representation Scheme
to represent models, schema, and instances uniformly
along with a visual representation
Mapping Formalism
to convert information from one scheme to another
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18. Context: Superimposed Information Research
Layer
Base
Information
Source1
mark
Model
Schema Data
Instance Data
NSF Digital Libraries 2 Program “Tracking Footprints through a Medical Information Space”
NSF Digital Government Program “Harvesting Information to Sustain our Forests”
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19. Applications SLIM Pad XML Extractor
Scratchpad application with Bundle-Scrap model (uses superimposed information)
XML Extractor
“Extracts” XML information and transforms it into a Topic Map for searching/browsing in
out
mapped
XML
Extractor
stored
DBMS
XML Files
Generic Rep.
(XML model)
Generic Rep.
(TM model)
Topic Map Browser
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21. The Metamodel Definition
connects 2
constructs
Basic
Metamodel
Elements
Structural
Connector
Construct
Special Elements
Mark
Lexical
Conformance
Generalization
Construct: A basic structural unit
Mark: A connection-point to the base-layer
Lexical: A primitive-value type
Connector: A relationship between 2 constructs
Conformance: A schema-instance relationship
Generalization: An inheritance between constructs
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22. The Metamodel in RDF Schema
(type, “Construct”, Class)
(type, “Mark”, Class)
(subClassOf, “Mark”, Construct)
(type, “Lexical”, Class)
(subClassOf, “Lexical”, Construct)
(type, “Connector”, Property)
(domain, “Connector”, Construct)
(range, “Connector”, Construct)
(type, “Conformance”, Property)
(subPropertyOf, “Conformance”, Connector)
(type, “Generalization”, Property)
(subPropertyOf, “Generalization”, Connector)
Construct Definitions
Connector Definitions
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23. The Metamodel in RDF Schema (cont.)
(type, “domainMult”, ConstraintProperty)
(domain, “domainMult”, Connector)
(range, “domainMult”, String)
(type, “rangeMult”, ConstraintProperty)
(domain, “rangeMult”, Connector)
(range, “rangeMult”, String)
(type, “instanceOf”, Property)
(instanceOf, “String”, Lexical)
(instanceOf, “Number”, Lexical)
Constraint Definitions
Creation Property
Some Default Primitive
Types
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24. Superimposed Information
“Digital Duct Tape”
A layer of data placed over (and separate from) existing information sources
Marks connect the superimposed and base layers
Examples
XML
Topic Maps
RDF
Model
Superimposed
Layer
Schema Data
Instance Data
mark
mark
mark
Base
Layer
Information
Source1
Information
Source1
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