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2nd Project Review – Växjo (Sweden)September 2004
COLDEX WP6
Community support through the LOR
LTCS (FUELTCS (FUE--UNED)UNED)Beatriz Barros, Beatriz Barros, M. M. Felisa VerdejoFelisa Verdejo ,,
J.Ignacio Mayorga, J.Ignacio Mayorga, TimTim ReadRead, Javier , Javier VelezVelez, , Yolanda Calero, Carlos Yolanda Calero, Carlos CelorrioCelorrio, Emilio Lorenzo, Emilio Lorenzo
COLLIDE (UDUI)COLLIDE (UDUI)Ulrich HoppeUlrich Hoppe, María , María OlingerOlinger, , Niels PinkwartNiels Pinkwart
10.09.2004 2nd Project Review – Växjö (Sweden)
Outline
IntroductionGeneral architecture– View Layer– Model Layer– A Coldex Portal Demo…
A view to relate the components and layers
– Persistence Layer
Further work
10.09.2004 2nd Project Review – Växjö (Sweden)
Introduction
To support learning groups and communities to work in context; either from a group view, from a task view,..
Social navigation
Learning objectsdescription facilitating co-construction ( reuse & share & enrich..)
Technical requirements– Distributed communities– Modelling approach allowing flexibility, adaptability and evolution
10.09.2004 2nd Project Review – Växjö (Sweden)
General Architecture
View Layer. For interaction purposes– Actions. Bridge to model layer
Social ManagerLO Repository Knowledge Manager
HIB
ER
NA
TE
CO
LDE
XP
OR
TAL
KM
SM
LOR
Ontology
Syn
chro
nize
rActionsActionsActions
ActionsActionsActions
ActionsActionsActions
View Layer Model Layer Persistence Layer
DB
C-J
DB
C
D.6.3.1D.6.3.1
10.09.2004 2nd Project Review – Växjö (Sweden)
General Architecture
Model Layer. Handles the execution of all the services that makes up the system– Modules
Social ManagerKnowledge Manager
– ServicesLO RepositorySocial BrowserNewsChatMail…
D.6.3.1D.6.3.1
HIB
ER
NAT
E
CO
LDE
XPO
RTA
L
KM
SM
LOR
Ontology
Syn
chro
nize
rActionsActionsActions
ActionsActionsActions
ActionsActionsActions
View Layer Model Layer Persistence Layer
DB
C-J
DB
C
10.09.2004 2nd Project Review – Växjö (Sweden)
General Architecture
Persistence Layer. Offers the mechanism to provide persistence for all the storage needs of the system– Data Persistence
Data BaseC-JDBCHibernate
– KnowledgeProtégé OntologyAlgernon
HIB
ER
NA
TE
CO
LDE
XP
OR
TAL
KM
SM
LOR
Ontology
Syn
chro
nize
rActionsActionsActions
ActionsActionsActions
ActionsActionsActions
View Layer Model Layer Persistence Layer
DB
C-J
DB
C
D.6.3.1D.6.3.1
10.09.2004 2nd Project Review – Växjö (Sweden)
The Portal
The portal– The portal is a web application that constitutes a
communication and coordination medium for the virtual communities. It provides access, within a context, to the available services
– It consists of Workspaces as an environment where users can interact through the repository, while they develop learning activities, mainly, in a collaborative way. Services that offer interaction means between users both in a direct or indirect way (LOR, Forum, Polls, …)
View Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Social Manager
Social Manager– This module stores all the information related to social
aspects such as the users that can connect to the system, the organisation of groups, previously active sessions…
– Functions:To administrate the system users, register new users and delete old ones.To manage the working sessions of each user (login / logout)
To manage the social model specified by the system administrators.
ChemistryCommunity
Administrator
Teacher
Bencedine
Student
Student
Student
Monitor
Organic Group
Student
Student
Student
Monitor
GlycerineGroup
Student
Student
Student
Monitor
Felisa
Carlos
Beti
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Social Manager
The social Model
– Actor. Represents a user stereotype within the portal– Group Template. Represents a stereotype of a collective of users– User. Represents a real user within the portal– Group. Represents a collective of users fitting a group template
User Actor
Group Group Template
embodies
fits
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Portal
The portal
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
Chemistry Community LOR
The LOR Service
Learning Object Repository (LOR) Service– Each social context provides a LOR service where users can
store and manage LOs within the Coldex server
– FunctionsTo upload and metadocument objects of a variety of typesSemantic searching and field based searchingTo view the contents of the LOR without having to download it
ChemistryCommunity
Administrator
Teacher
Bencedine
Student
Student
Student
Monitor
Organic Group
Student
Student
Student
Monitor
GlycerineGroup
Student
Student
Student
Monitor
Glycerine Group LOR
Organic Group LOR
Inorganic Group LOR
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The LOR Service
The LOR within its social context
– Users, Groups and Actors are abstracted as social units– Each social unit has a social context with a collection of services– LOR is a service
User Actor
Group Group Template
embodies
fits
Social Unit Social Context
Service
Repository ...
nn
n
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Portal
The portal
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
A Coldex Portal Demo…
A demo…Showing the workspace areaUploading and metadocumenting a new Learning ObjectTo Move/Copy/Delete learning objectsContextual Searching in LOR
– Metadata searching– Semantic Searching
– Join/Create groups and users
Start here!
10.09.2004 2nd Project Review – Växjö (Sweden)
The Metadata
Several metadata schema are used by partners– A common set as a minimum consensus of metadata– Each partner extends this set defining a new LO type
Model Layer
Find by consensus
Defined by each partner
D.7.2.2D.7.2.2
10.09.2004 2nd Project Review – Växjö (Sweden)
The Metadata
The Metadata problem– Filling metadata is
Very time consuming and heavy to be done by handA error prone process
– The server and tools can assist automating this process The automatic populating of metadata exploits context info– Resource Spy. Extract info from the resource to upload– Social Spy. Extract info from social context– Workspace Spy. Extract info from workspace area– System Spy. Extract info from system
Model Layer
D.7.2.2D.7.2.2
10.09.2004 2nd Project Review – Växjö (Sweden)
The Metadata
To exploit extracting capabilities from resources– A mapping schema is included in the packaging model
Model Layer
MyMoon.zip
Manifiest.xml
Contents
<?xml version="1.0" encoding="UTF-8"?><metadata>
<metadataItem name="name">My Moon</metadataItem><metadataItem name="version">1.0</metadataItem><metadataItem name="keyword">coolmodes</metadataItem><metadataItem name="keyword">mymoon</metadataItem><metadataItem name="date">2004/04/16 14:26:53</metadataItem><metadataItem name="language">en</metadataItem><metadataItem name="editors"/><metadataItem name="palettes">Moon</metadataItem><metadataItem name="palettes">Graphical Calculator</metadataItem><metadataItem name="palettes">DrawPalette</metadataItem><metadataItem name="project"/><metadataItem name="activity"/>
</metadata>
<?xml version="1.0" encoding="UTF-8"?><metadata>
<metadataItem name="name">My Moon</metadataItem><metadataItem name="version">1.0</metadataItem><metadataItem name="keyword">coolmodes</metadataItem><metadataItem name="keyword">mymoon</metadataItem><metadataItem name="date">2004/04/16 14:26:53</metadataItem><metadataItem name="language">en</metadataItem><metadataItem name="editors"/><metadataItem name="palettes">Moon</metadataItem><metadataItem name="palettes">Graphical Calculator</metadataItem><metadataItem name="palettes">DrawPalette</metadataItem><metadataItem name="project"/><metadataItem name="activity"/>
</metadata>
D.7.2.2D.7.2.2
10.09.2004 2nd Project Review – Växjö (Sweden)
A Coldex Portal Demo…
A demo…– Show the workspace area
Continue here!Uploads and metadocument a new Learning ObjectMove/Copy/Delete learning objects
– Search in LORo task contextualizedo workspace contextualized
through metadatasemantic searching
– Join/Create groups and users
10.09.2004 2nd Project Review – Växjö (Sweden)
task contextualizedqueries
Continue demo!
10.09.2004 2nd Project Review – Växjö (Sweden)
Knowledge Manager
Knowledge Manager– Manages the conceptual model about the COLDEX
communities and their experimental activities . This component is an abstraction to capture and represent separately the relevant information from the actual code that implements it.
Reification (i.e. To represent explicitly relevant objects of the social and repository components) to provide them with a declarative semanticsTo offer searching facilities exploiting not only instances but also the reified objects and relations.
– We have chosen Protégé as our knowledge representation because of its versatility and ease of use; with two pluginsfor reasoning, Protégé Axiom Language (PAL) and Algernon
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Knowledge Manager
The Knowledge Manager
– Support of several reasoning and query languages (Algernon, Pal,…)– Storage of ontological queries on database– The synchronizer
loads ontology at startingUpdates ontology on demand
KnowledgeManager
PALEngine
SearchEngine
SearchEngineFactory
PALQueryBean AlgernonQueryBean
QueryBean
+ execute (QueryBean query)
AlgernonEngine
<<create>>
<<use>><<use>>
Query Repository
Persistence Layer
DB
Synchronizer
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
Code To Ontology relationships
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Data PersistencePersistence Layer
Distributed persistence with replicated database
– Persistence Layer. To offer transparency – Hibernate. Object to relational Data Mapping tool– C – JDBC. Database cluster middleware to manage replication– MySQL. Database manager
DB ColdexServer 1
InternetDB ColdexServer 1
DB ColdexServer 1
D.6.3.1D.6.3.1
DB
HIB
ER
NA
T E
MySQL
Per
sist
ence
C-J
DB
C
10.09.2004 2nd Project Review – Växjö (Sweden)
Further work
Further work– Integrate services with the tools– Extend some features – Support the activities of the OU Schema – Evaluate the usability of the semantic query functionality– Perform an experimental study of scalability
10.09.2004 2nd Project Review – Växjö (Sweden)
References
D.6.3.1D.6.3.1
D.7.2.2D.7.2.2
Coldex System Architecture Summary.July, 2004. UNEDVerdejo, M.F Barros, B. Read, T. Mayorga, J.I Vélez, J. Calero, YCelorrio, C. & Lorenzo, E.J.
UNED contribution to Functional Documentation. July, 2004. UNEDVerdejo, M.F.; Barros, B; Mayorga, J.I.; Vélez, J
10.09.2004 2nd Project Review – Växjö (Sweden)
Code To Ontology relationships
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
Code To Ontology relationships
Model Layer
10.09.2004 2nd Project Review – Växjö (Sweden)
The Data PersistencePersistence Layer
Distributed persistence with centralized database
– Persistence Layer. To offer transparency– Hibernate. Object to relational Data Mapping tool– MySQL. Database manager
DB
ColdexServer 1
ColdexServer 2
ColdexServer 3
InternetDB
HIB
ER
NA
TE
MySQL
Per
sist
ence
D.6.3.1D.6.3.1
10.09.2004 2nd Project Review – Växjö (Sweden)
The KnowledgePersistence Layer
DB
Ontology
Alg
erno
nS
ynch
roni
zer
Knowledge level
– Ontology empty at startingStart loadingUpdate on demandVolatile data. Only in memory for reasoning purposes
10.09.2004 2nd Project Review – Växjö (Sweden)
Frequently asked questions
Persistence Layer
Why not to use only the persistence mechanism provided by Protégé ?– Some functions do not need to use the knowledge level– These functions are efficiently managed by a relational
scheme– Ontology persistence has a less flexible scheme for storage
Why LDAP approach was discarded?– LDAP is a suitable approach to implement LORs– Other functions require relational capabilities – A Relational scheme is a better approach to implement the
portal
10.09.2004 2nd Project Review – Växjö (Sweden)
UNED Pilot (formative evaluation)
March-April 2003March-April 2004– System funcionality– Learning improvement– Critical issues for deploymentritical issues for deployment
Organizational levelInfrastructure level
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