Transcript スライド 1

Introduction to Framework for Metamodel
Interoperability： ISO/IEC19763
9th Open Forum on Metadata Registries
Harmonization of Terminology, Ontology and Metadata
20th – 22nd March, 2006 , Kobe Japan.
Day 1:
Slot No. P3
Name: Hajime Horiuchi
Organization: Tokyo International University
Where We Are Now
Information
Productivity
Information
Engineering Concerns
Metamodel Oriented
Model Oriented
Object Oriented
Data Oriented
Semantic
Interoperation
Business
Collaboration
BPR
Office
Automation
Process Oriented
SIS
Core Businesses
Computerization
Calculation
Problem
Solving
1960
1970
Web2.0
Internet + Web Tech.
System Reconstruction
With DBMS
1980
1990
2000
9th Open Forum for Metadata Registry, Kobe, 2006
2010
Internet, today & tomorrow
Web Service
Web Service
Web Service
Internet
Web Service
Portal
B2B Business
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata Standardization Activities
UBL
HL7
OASIS Reg/Rep
ISO TC127
UN/CEFACT ebXML RIM
Earth Moving
machine
XML Registry
W3C
UDDI
XML,RDF,
OWL
Health
Informatics
Metadata
Standardization
UDDI
OMG
MOF, CWM,
ODM
Geographical data
ISO/IEC
11179
MDR
Metamodel
Framework
ISO TC 204
SQL
Catalog
E-Commerce
metadata
Library
metadata
ISO TC 46
Dublin Core
ISO TC211
Intelligent Transportation
Systems
Terminology
ISO TC 37
ISO TC 215
ISO/IEC JTC1 SC32
Topic map
ISO/IEC JTC1 SC34
Ｌｅａｒｎｉｇ Ｍｅｔａｄａｔａ
ISO/IEC JTC1 SC36
9th Open Forum for Metadata Registry, Kobe, 2006
TC154
ebXML
Type of Metadata Standards
Metadata Value
•ebXML RIM
•ISO/IEC19763(MMF)
Metadata
Instances
Registry
Representation
Administrative
Attributes,
Representation
Language
Storing Structure
•ISO/IEC10728(IRDS）
•ISO/IEC11179（MDR)
•ebXML Repository Service
•ebXML Core Component,
•Dublin Core,
•RSS
•Digital Library
•Image Processing
•Geographical Map
•Broad Casting Program
•Health Care
•elearning
•etc
XMDR
•MOF(ISO19502)、
•RDF、
•OWL、
•Topic Map
9th Open Forum for Metadata Registry, Kobe, 2006
Subject Areas of Standardization
Describing
RDF,
OWL
Concept
Registration
Service Interface
IRDS,
ebXML RS
Metamodel
MOF, 11179,
ebXML RIM
Meta
Information
Interchange
Contents
Attributes
Registration ebXML CC,
IRDS,
Dublin
Core
Aspects
11179,
ebXML RIM
MMF
Common elements
Values
ISO Codes
9th Open Forum for Metadata Registry, Kobe, 2006
Format
CDIF,
XMI,
PDES,
History of Metadata
2000~
Metadata for
Semantics Sharing
Stage III
1990~
Metadata for Information
Sharing
Registry
1980~
Stage II
Metadata for Software
Developments
Repository
1980~
Metadata for DBMS
1970~
Metadata for file items
DD/DS
Data Dictionary
9th Open Forum for Metadata Registry, Kobe, 2006
Stage I
Evolution of Metadata minds
Stage I
Stage II
Stage III
Elements
Common Bases
Describing it’s
structure
Sharing elements
Capturing &
representing of
Relationships
9th Open Forum for Metadata Registry, Kobe, 2006
Stage I
Target
Metadata
Insight of data
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata concept in the Stage I
IRDS（ISO/IEC10728）
Metadata Item
Metadata Repository
Item name
Metadata
Data Type
Date of Update
Start Time
Date & time
2004.01.02/9:00
Name
Person name
2004.01.03/9:00
Instance of Metadata
Data Item (Type)
Start time
Name
2004.02.24/10:00
John Smith
2004.02.24/10:00
Tom Johns
Data Instance
Value
9th Open Forum for Metadata Registry, Kobe, 2006
The first meta hierarchy concept
ISO/IEC 10027 （IRDS Framework） & 10728 （IRDS Service Interface）,1992
Meta-Meta
DataStore Component
File
M3
Table
Column
Meta
Attr
Table
Column
Emp
EmpNo
Numeric
Name
string
Address
string
Emp
Type
Instance
EmpNo
Name
Attr
M2
M1
Address
001
吉田
東京
002
三木
千葉
003
佐藤
埼玉
M0
ISO/IEC19502 (MOF) inherited
the same idea
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata concept in the stage
II
Target
data
Metadata
Common Base
Common base &
data
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata concept in ISO/IEC11179
ISO/IEC 11179 Series of standards
DEC
Conceptual Domain
Data Element
Concept
DEC Administration: 0..1
Object Class: 0..1
Property: 0..1
0..N
+Specifying
+Having
Person
name
CD Administration: 0..1
Value Meanings: 0..N
1..1
CD
Japanese
name
Chinese
name
US Name
1..1
1..1
+Expressed by
+Represented by
+Representing
+Expressing
0..N
0..N
0..N
+Representing
+Represented by
VD Administration: 1..1
Permissible Values: 0..N
Description: 0..1
Data Type: 1..1
VD
Chinese
Character
Value Domain
Data Element
DE Administration: 1..1
Derivation: 0..1
DE
Employee
Name
1..1
Common Base
9th Open Forum for Metadata Registry, Kobe, 2006
Kana
Metamodel for ISO/IEC11179
PAGE 1
11179-3 METAMODEL
Main Model
data_element_concept_conceptual_domain_relationship
Data_Element_Concept
+having
<<Required>> administered_component : Administered_Component
<<Optional>> object_class : Object_Class
<<Optional>> object_class_qualifier
<<Optional>> property : Property
<<Optional>> property_qualifier
1999-12-13
Proposal for Comments
11179-3 Revision
DD Mann
+specifing
1..1
0..*
Conceptual_Domain
<<Optional>> administered_component_information : Administered_Component
<<Optional>> dimensionality
0..*
+contained_in
0..1
1..1
1..1
1..*
+containing
+specified_by
+containing
0..*
+represented_by
0..*
+containing
+contained_in
value_meaning_set
NOTE:
comceptual_domain_relationship
This model represents the logical structure of
a registry for data elements and related
components that are in a "recorded" or higher
registration status.
Data_Element_Concept_Relationship
DCE
CD
+contained_in
<<Required>> type_description
0..*
Value_Meaning
For UML v1.3 documentation see:
ftp://ftp.omg.org/pub/docs/ad/99-06-08.pdf
<<Required>> identifier
<<Optional>> description
<<Required>> begin_date
<<Conditional>> end_date
data_element_concept_relationship
1..*
2..n
+contained_in
+represented_by
permissib le_value_meaning
expression
+representing
0..*
Permissible_Value
<<Required>> item
<<Required>> begin_date
<<Conditional>> end_date
Rule
<<Optional>> administered_component : Administered_Component
<<Required>> description
permissib le_value
specification
2..n
1..1
+is_formula_for
+member_of
allowed_value
Example
+containing
+specifing
derivation
<<Required>> item
0..*
1..*
+used_by
0..*
1..*
Non_enumerated_Domain
Enumerated_Domain
<<Required>> description
+representing
Source_Data_Element
0..1
+is_input_to
exemplication
DE
0..*
value_domain_relationship
+containing
VD
Value_Domain_Relationship
<<Required>> type_description
derivation_output
derivation_input
+containing
+providing_representation_to
0..*
+represented_by
1..*
+resulting_from
1..1
+contained_in
0..*
1..*
<<Required>> administered_component : Administered_Component
<<Required>> representation_class : Representation_Class
<<Optional>> representation_class_qualifier
Value_Domain
+contained_in
Data_Element
representation
0..*
+providing_representation_for
+representing
0..*
0..1
<<Optional>> administered_component : Administered_Component
<<Optional>> name
<<Required>> datatype : Datatype
<<Optional>> maximum_character_quantity
<<Optional>> minimum_character_quantity
<<Optional>> format
<<Optional>> unit_of_quantity : Unit_of_Quantity
1..1
+represented_with
9th Open Forum for Metadata Registry, Kobe, 2006
ebXML Core Components Structure
Name
ACC: Person
Home Address
ASCC:
ASCC:
Work Address
Work for
Live in
ACC
Common
Base
Address
Aggregated
BCC
Country
Postal code
Town
Inherited
CCT
Codes
Identifier
Text
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata concept in the stage
Target
data
III
Concept
Common Base
Metadata
Target
data
Concept
Relationship among data
Common Base
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata concept in the Stage
Stage III
III
To try to represent a concept completely, there
must be means to describe relationships to
others.
RDF
TOPIC Map
OWL
MMF
XMDR
9th Open Forum for Metadata Registry, Kobe, 2006
RDF（Resource Description Framework）
Triple
Resource
Document 1
Property
Value
Author
“John Smith”
<?xml:namespace ns =
"http://www.w3.org/RDF/RDF/" prefix ="RDF" ?>
<?xml:namespace ns = “http://purl.oclc.org/DC/” prefix = “DC” ?>
<RDF:RDF>
<RDF:Description RDF:HREF = “http://uri-of-Document-1”>
<DC:Creator>John Smith</DC:Creator>
</RDF:Description>
</RDF:RDF>
9th Open Forum for Metadata Registry, Kobe, 2006
However……
9th Open Forum for Metadata Registry, Kobe, 2006
Metadata concept valiations


A data which describes other data
A data which provides Syntax of an elements
But, is “Type & Instance” the only way for formulating
the metadata ?
Metadata
Represent
Instantiate
Data Instance
9th Open Forum for Metadata Registry, Kobe, 2006
Complex Obejcts Representaion


How to represent difference among same components which
are in different orders or structure
Structured composite objects
Order
Ｏｒｄｅｒ date
YY
Japanese
Calendar
MM
DD
MM
?
DD
YY
ISO
Calendar
9th Open Forum for Metadata Registry, Kobe, 2006
Different views on an entity
For Sales
For AP/AR
For CRM
Customer
Customer
Customer
Customer Id.
Company code.
Customer
Address
Address
Address
Contact name
Invoice No.
History of trans.
Invoice issue
date
9th Open Forum for Metadata Registry, Kobe, 2006
Different views in relationships (?)
Customer
Customer
n
Order
m
Products
Products
9th Open Forum for Metadata Registry, Kobe, 2006
Solutions to be discussed
 Needs
for features to represent various
types of relationship
 Needs for Complex type of objects
(Not only for program data type)
 Normative view points of meta
information
9th Open Forum for Metadata Registry, Kobe, 2006
Relationships are not in one type
Y
W
Super - Sub
Type Instance
X
Z
Syntax Expression
Base Variant
9th Open Forum for Metadata Registry, Kobe, 2006
V
Another Issues :
A lot of registreies in different
concept and protocols
9th Open Forum for Metadata Registry, Kobe, 2006
Heterogeneous Registries Environment
ebXML
Registry
EAN
Registry
GCI
Registry
RosettaNet
Registry
CPFR
Registry
Component
Registry
Business
Negotiation
UDDI
Vender Shipper
Catalog Catalog
Production Planning
Business
Category
Consumer
Profile
System
Development
REACH
CALS
Manufacturing
Customer
PDES/STEP
Support
Registry
Shipping
9th Open Forum for Metadata Registry, Kobe, 2006
Registry Interoperation
with Metamodel Framework
9th Open Forum for Metadata Registry, Kobe, 2006
What is MMF
9th Open Forum on Metadata Registries
Harmonization of Terminology, Ontology and Metadata
20th – 22nd March, 2006 , Kobe Japan.
Day 1:
Slot No. P3
Name: Hajime Horiuchi
Organization: Tokyo International University
Stage IV
Stage III
Stage IV
Common Infrastructure
9th Open Forum for Metadata Registry, Kobe, 2006
ISO/IEC19763 (MMF)




ISO/IEC19763-1: Reference Model (JP,UK)
ISO/IEC19763-2: Core Model (JP, Kr)
 FCD balloting completed on 1st March 2006
ISO/IEC19763-3: Metamodel for Registering
Ontology (Cn, JP)
 3rdCD balloting will close on 20th March 2006
ISO/IEC19763-4: Metamodel for Model
Mapping (JP)
 CD registered at April, 2005
9th Open Forum for Metadata Registry, Kobe, 2006
Part-1: Reference Model
Part-2 :
Metamodel framework core model
Part-3:
Part-4:
Metamodel framework
for Ontology
Metamodel framework
for Model Mapping
Part-5:
Metamodel framework for Model Constructs
Part-6:
Registration Procedure
9th Open Forum for Metadata Registry, Kobe, 2006
Meta Modeling
Facility (MOF)
Defining Facility
(ISO11179 MDR)
Core model of Meta model framework
Metamodel for Ontology
registration
Metamodel for
Model Mapping
Ontology
Metamodel for
Model Constructs
Mapping Rules
metadata
Mapping
Targets
Codes
Sharable
model
Model
mapping rules
Common
Modeling Facility (UML)
Value Domains
Patterns
Common modeling
Constructs
9th Open Forum for Metadata Registry, Kobe, 2006
Objectives of
MMF Family of standards
 Provide
common metamodel as a
framework to register various types of
• metamodels
• models (Ontologies)
• modeling constructs
to enable them to be
• Sharable
• Reusable
• Exchangeable
9th Open Forum for Metadata Registry, Kobe, 2006
Metamodel Framework Architecture
Core Model
inherit
M3
Metamodel Framework
inherit
M2
Metamodel
Metamodel
describe
Model
Modeling
Facility
refer
Common Data
Element
use
M1
Object Patterns
Modeling Constructs
M0
Values
Object
Real World
9th Open Forum for Metadata Registry, Kobe, 2006
Targets to be Registered
– Metamodels
• Modeling Facility metamodels (e.g. UML, etc.)
• Registry metamodels (e.g. ebXML R&R, UDDI, )
– Domain models
• Various business application models (UML based, IDEF1X
based, )
• Ontology models
• Terminology
– Modeling Constructs
• Basic Information elements metadata (e.g. ebXML Core
Components)
• Normative Codes
• Modeling Patterns
• Modeling View definitions (RM-ODP)
• Basic Terminologies
9th Open Forum for Metadata Registry, Kobe, 2006
How to represent relationships
Upper Model
ISO/IEC 19763-2 :
Framework for Metamodel
Framework for Interoperability:
Core Model
•Type and Instance
•Super and Sub
•Base and Variant
•Abstract Syntax and Expression
Target Model
9th Open Forum for Metadata Registry, Kobe, 2006
Association Types
code
name
description
T-I
Type-Instance
“Type-Instance” is an association type between a class and its object. Also,
the class diagram in a model package and its object diagram may be
included.
S-S
Super-Sub
“Super-Sub” is an association type between a super class and its inherited
sub classes. Also a model package and its sub packages may be included.
B-V
Base-Variant
“Base-Variant” is an association type between a base model and its variant
models that are created by modifying the base model according to the
permitted operation. There are operations such as renaming, specifying,
refining, substituting, extending and merging. See Table F1 in Annex F.
In the association type “Base-Variant” many operations above are performed
on a base model partially and many times. Eventually, the lower model will be
derived from the upper base model. The detail specification on specifying
operations should be provided as a ModelSpecification for each registering
target.
A-E
Abstract
SyntaxExpression
“ Abstract Syntax-Expression” is an association type between an upper
metamodel and a lower model. In this case, the ModelByMOF in a
ModelDomainProfile provides a metamodel. The lower model must be
described according to the abstract syntax. Usually, stereotypes of UML are
defined by such metamodels as a UML profile. The lower model will be drawn
using those stereotypes.
9th Open Forum for Metadata Registry, Kobe, 2006
Concept of MMF-2 (ISO/IEC CD 19763-2)
Inherit MOF
Upper Model
Model Type
Classifier
Model
Sign
Model
Concept
Model Domain
Profile
Attachment
Model
Selection
Model
Instance
XMI schema
Target of
registration
A Model
Model Specification
Document
9th Open Forum for Metadata Registry, Kobe, 2006
MMF-2 Packages
MOF
M3 Layer
<<instanceOf>>
M2
Layer
<<instanceOf>>
MDR-ByMOF
<<instanceOf>>
M2,M1,..,M-n
Layer
MMF-Core
ModelClassifier
<<use>>
<<use>>
<<reference>>
Target
<<reference>>
ObjectByMOF
<<use>>
<<use>>
Level Pair
<<reference>>
<<use>>
Registry
MMF-Core Models
<<use>>
Relationship
Target Models
<<use>>
MMF-Core Models
Target Models
9th Open Forum for Metadata Registry, Kobe, 2006
MMF Core High level Metamodel
ModelDomain
Profile
conformance
0..*
ModelSign
namespace
sign
+specified by
ModelClassifier
1
model type
+specified by ModelConcept
+concept usage type
modelType
xmi text
1
0..1
attachment type
1
attachment
1
+associated by
+having
0..*
1
+generally expressed by
Administered Item
1..*
+expressing 1..*
ModelSelection
condition
1..*
+selected by
+refersTo
ModelInstances
1 association type
component type
+selecting format
1
0..* ModelComponent
+has
9th Open Forum for Metadata Registry, Kobe, 2006
Metamodel of Registered
Target Structure
PackagedObject
0..1
NamedElement
1..*
+has
Administered Item
+constructs
ModelSpecification
format
original
source
issue date
version
+descriptions status
0..* titile
purpose
scope
normativeReference
termDefinition
comformance
1
ModelByMOF
model layer level
isMOFcompliant
MOFversion
+defined with UML
ModelDomain
Profile
1 conformance
+specified by
0..*
0..1
ModelConstructs
ModelClassifier
model type
usage type
xmi text
attachment type
attachment
+typed models
+consist of
ModelComponent
0..*
0..*
+external references
ModelSelection
condition
9th Open Forum for Metadata Registry, Kobe, 2006
MMF Core
Scope
Ontology
Registration
ScopeofofMM
MMF
Ontology
Registry
MM
Ontology
Registration
MMF
Ontology
Registry
.
.
Registry Info. C .
Registry
A Information
OntologyInfo.
Registry
Ontology Registry Information
for Ontology A
for Ontology A
.
.
Ontology C .
Ontology
A
for application
system C
for application system A
OntologyRegistry
for Ontology B
Standardiz
Standardized
Ontology
Ontology
Repository
Repository
Application
Application
System A
System A
Registry Info. B
Ontology Registry Information
Standardized
Ontology
Repository
Interoperation
Ontology B
for application system B
Application
System B
9th Open Forum for Metadata Registry, Kobe, 2006
Meta-meta model of MOF
Core Model
MMF for Model Mapping
Transformation
Trans Patterns
Relation
Trans Rule
9th Open Forum for Metadata Registry, Kobe, 2006
Global Industry Federation Model
Each global industry, one federation !
Super NRR
International Fed
NRR1
Trade
RR
NRR2
NRR3
Trade
RR
Steel
RR(FLR)
Steel
RR
National Fed. 1
Global Industry Fed.
National Fed. 2
Steel
RR
National Fed. 3
9th Open Forum for Metadata Registry, Kobe, 2006
Common Infrastructure
for Registry Interoperations
ISO 11179
Registries
Common
Viewpoints,
Software
Component
Registry
UDDI
Registries
Common
Content
Common Content
Classifications,
&
Ontology
OASIS/ebX
ML
Registries
Common Content
Common Content
Interoperati
on
CASE Tool
Repositorie
s
Common Content
Database
Catalogs
Ontological
Registries
Common Content
Common Content
Common
Meta-modeling
Facilities
(MDR, MOF,
MMF)
Common Model Constructs
(Normative Metadata/Metamodel Elements)
9th Open Forum for Metadata Registry, Kobe, 2006
What will come
as the Next Stage ?
9th Open Forum on Metadata Registries
Harmonization of Terminology, Ontology and Metadata
20th – 22nd March, 2006 , Kobe Japan.
Day 1:
Slot No. P3
Name: Hajime Horiuchi
Organization: Tokyo International University
Describing meta information might be
…
Stage IV
Common Infrastructure
Common Infrastructure
9th Open Forum for Metadata Registry, Kobe, 2006
Winner Takes All
Rich men become more rich and poor men become more poor
(by Preferential Attachment 優先的選択）
Portal
Yahoo,
Number
of Nodes
Google
MSN,
Registration
Authority
REACH(EU),
EPA,
Global
Identification,
Etc.
Number of Links
9th Open Forum for Metadata Registry, Kobe, 2006
Someday….
Self-Contained
Giant
Register
No Alignment
Giant
Register
Different
Protocol
9th Open Forum for Metadata Registry, Kobe, 2006
What is Registration
Registrations are needed for;
•Sharing resources or information
•Maintaining reliability
•Proof a fact
and so on.
However,
9th Open Forum for Metadata Registry, Kobe, 2006
REACH of EU
Registration Evaluation & Authorization of
CHemicals
 Ask to all of manufactures or retailers who handle
chemical materials, in the forms of “Substance”,
“Preparation” & “Article”, to register the deals
 IUCLID: International Uniform Chemical
Information Database (More than 100,000
materials)

http://europa.eu.int/comm/enterprise/reach/index_en.htm
9th Open Forum for Metadata Registry, Kobe, 2006
Repository Interoperability
Vs Repository Democracy
Each registry follows a common standard
Registry
Alignment
Alignment
(Mapping)
(Mapping)
Registry
Registry
Each registry user has own autonomy in
choosing a registry
9th Open Forum for Metadata Registry, Kobe, 2006
The Requirements for Next MDR standards
Common Facility for
MDR/MMF
ISO/IEC19502(MOF)
ISO/IEC11179 (MDR)
Metamodels for
Basic Ontology
Constructs
Ontology
Evolution
ISO/IEC 19763 (MMF)
Registration
Metamodel
Content
Management
XMDR Registry
Normative Basic
Elements
Terminology
Basic Classes
Basic Relationship
ODM Metamodel f
CL
ODMorMetamodel
for OWL
Ontologies
Analysis and
Extraction
Registering
9th Open Forum for Metadata Registry, Kobe, 2006
Query
Service
Common Facility for MDR/MMF
Common Facility
Actual
Identifications
Terminology
Identification
Name Space
Classification
Administered Item
Actual
Name Spaces
MDR/MMF
Actual
Classifications
Metamodels
Domain
ODM
Ontology
9th Open Forum for Metadata Registry, Kobe, 2006
Thank you
Prof. Hajime Horiuchi,
[email protected]
http://www.tiu.ac.jp/org/forum-01/
http://www.umtp-japan.org/
9th Open Forum for Metadata Registry, Kobe, 2006
FYI
9th Open Forum for Metadata Registry, Kobe, 2006
Famous Konigsberg Bridges Problem
Konigsberg is a city which was the
Leonhard Euler
capital of East Prussia but now is
(1707-1783) 9th Open Forum for Metadata
knownRegistry,
as Kaliningrad
Kobe, 2006in Russia.
A new bridge for solving the problem
They built a new bridge to
solve the problem (1875)
9th Open Forum for Metadata Registry, Kobe, 2006
Registry might be…

A Registry might be a bridge (HUB)
to enable arbitrary links to change
characteristics of whole networks.
9th Open Forum for Metadata Registry, Kobe, 2006
Small World and Scale Free Network
Every peoples on this world are connected in the
“Six Degrees Separation”
Duncan. J. Watt & Steven H. Strogatz
 Internet enabled direct connections among nodes
which formulate the Scale Free Network.
Albert L. Barabasi

 What were brought by the Scale Free
Network?
9th Open Forum for Metadata Registry, Kobe, 2006
Scale Free Network & Power Law
Random
Scale Free
Network
Network
Provability of links at a node = same
Number of
Nodes
P(K)
P(K)
∝
K-γ
Number of Link (K)
9th Open
Forum
for Metadata
Registry,
Kobe, 2006
Scale
Free
Network,
Albert
R. Barabasi
By the study of Barabasi,
γ
Ｎｅｔｗｏｒｋ type



WWW
Internet
Hollywood Stars
1.9 - 2.7
2.1 - 2.5
2.3 - 3.1
9th Open Forum for Metadata Registry, Kobe, 2006
Random Network Vs Scale Free Network
9th Open Forum for Metadata Registry, Kobe, 2006
Formal definition

Although no one definition is universally accepted, Li et al (2005) defined
a "scale-free metric". Let g be a graph with edge-set ε, and let the degree
(number of edges) at a vertex i be di. Define

This is maximised when high-degree nodes are connected to other highdegree nodes. Now define

where smax is the maximum value of s(h) for h in the set of all graphs with
an identical degree distribution to g. This gives a metric between 0 and 1,
such that graphs with low S(g) are "scale-rich", and graphs with S(g) close
to 1 are "scale-free". This definition captures the notion of self-similarity
implied in the name "scale-free".
From Wikipedia
9th Open Forum for Metadata Registry, Kobe, 2006
Potential Solutions in the
Standardization
Segregate Catalogues and Registers ?
 Conformance to the register should be
normalized carefully.
 The levels of conformance should be discussed
in the different process other than standard
development processes
 Registry Federation infrastructure
 Common base for Registries
 Repository Democracy
9th Open Forum
for Metadata Registry, Kobe, 2006
 Neutral Global
Standards
