Strategies for Aggregating Educational Content

Bram Vandeputte & Joris Klerkx

http://bit.ly/c6mRZChttp://bit.ly/bram-vandeputte

Key Technologies

• Metadata (IEEE LTSC LOM)

• describe learning resources with ICOPER AP

• Harvesting (OAI-PMH)

• get learning resource metadata and copy locally

• Federated Search (SQI)

• distribute issued queries to remote repositories

• Publishing (SPI)

• add new learning resources in ‘a’ repository

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Metadata & Educational Content

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IEEE LTSC IEEE LTSC LOMLOM

Example taken from: http://www.dlib.org/dlib/january08/ceri/01ceri.html

Harvesting with OAI-PMH

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5

How OAI-PMH works• OAI “VERBS”

• Identify

• ListMetadataFormats

• GetRecord

• ListIdentifiers

• ListRecords

• ListSets

HARVESTER

REPOSITORY

OAI OAI

Service Provider Metadata Provider

HTTP Request

HTTP Response

(OAI Verb)

(Valid XML)

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Example verb: ListRecords

• Purpose

• Retrieves metadata records for multiple items

• Parameters

• from – start date (O)

• greater than or equal to

• until – end date (O)

• less than or equal to

• set – set to harvest from (O)

• resumptionToken – flow control mechanism (X)

• metadataPrefix – metadata format (R)

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Example verb: GetRecord

• Purpose

• Returns the metadata for a single item in the form of an OAI record

• Parameters

• identifier – unique id for item (R)

• metadataPrefix – metadata format for the record (R)

Example OAI-PMH Calls

• Identify

• http://ariadne.cs.kuleuven.be/ariadne-partners/services/oai?verb=Identify

• ListMetadataFormats

• http://ariadne.cs.kuleuven.be/ariadne-partners/services/oai?verb=ListMetadataFormats

• ListRecords

• http://ariadne.cs.kuleuven.be/ariadne-partners/services/oai?verb=ListRecords&metadataPrefix=oai_lom

• http://ariadne.cs.kuleuven.be/ariadne-partners/services/oai?verb=ListRecords&resumptionToken=

• GetRecord

• http://ariadne.cs.kuleuven.be/ariadne-partners/services/oai?verb=GetRecord &identifier=oai:ariadne.cs.kuleuven.be:BLKLKP1382&metadataPrefix=oai_lom

• ... 8

Example :http://ariadne.cs.kuleuven.be/ariadne-partners/services/oai?verb=ListRecords&metadataPrefix=oai_lom

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OAI-PMH verbs

Setting up OAI-PMH Target

ARIADNE Harvester

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http://bit.ly/fA8e0U

• Incremental, scheduled harvesting

• Supports SPI specification

• Integrated with Registry, Validation, Identification, Transformation

• RSS Alerts

Validation Service

• Paste metadata record

• e.g LOM instance

• Select validation scheme uri

• e.g http://ltsc.ieee.org/xsd/LOM/strict

• Validate & Consult Validation Errors

• Based on XSD Schema & Schematron Rules

http://bit.ly/90va7d

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In markup languages, Schematron is a rule-based validation

language for making assertions about the presence or absence

of patterns in XML trees. It is a structural schema language

expressed in XML using a small number of elements and XPath.

In markup languages, Schematron is a rule-based validation

language for making assertions about the presence or absence

of patterns in XML trees. It is a structural schema language

expressed in XML using a small number of elements and XPath.

Example Validation

Service

http://bit.ly/90va7d

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Harvesting Infrastructure

External Repository

ARIADNE Harvester

validation serviceharvester log

OICS

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3344

55

66

Federated Search with SQI

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Simple Query Interface• CEN WS-LT specification (CWA 15454:2005)

• Neutral (Query Language + Result Format), e.g. PLQL for query + LOM for results

• Synchronous & asynchronous queries

• Stateful & Stateless Implementation

• Session Management

• Example SOAP endpoint:

• Session Management: http://ariadne.cs.kuleuven.be/ariadne-registry/services/SqiSessionManagement

• Target: http://ariadne.cs.kuleuven.be/ariadne-registry/services/SqiTarget

• Example RESTful endpoint:

• http://ariadne.cs.kuleuven.be/ariadne-registry/api/sqitarget?query=ariadne&start=1&size=1&lang=plql1&format=lom

http://www.dlib.org/dlib/january08/ceri/01ceri.html

Simple Publishing Interface

• Pull with harvest, publish with push technology

• CEN/ WS-LT CWA16097 SPI

• Facilitate metadata & resource publishing from client tools

• enable interoperability between components in OER federation

http://www.dlib.org/dlib/september10/ternier/09ternier.html

Collection Registry

http://bit.ly/cGdsYd 18

SPISQI OAI-PMH

ARIADNEARIADNEHarvesterHarvester

OICS

4.

CEN/WS LTS N 623

Data Model

IMS LODE REGISTRY MODELBASED ON THE ISO 2146 STANDARD: “REGISTRY SERVICES FOR

LIBRARIES AND RELATED ORGANIZATIONS

“Alliance to make shared online learning resources available to educators and students around the world”

http://www.globe-info.org/

>1.000.000>1.000.000

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68.00368.003

Thanks!Questions

?

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http://bit.ly/c6mRZC

Interested?