Building Repositories for Digital Learning Objects - The Sloan ...

candlewhynotΔιαχείριση Δεδομένων

31 Ιαν 2013 (πριν από 4 χρόνια και 5 μήνες)

232 εμφανίσεις

Building Repositories for Digital
Learning Objects: Challenges, Issues,
and Opportunities

Susan W.
Alman

& Christinger Tomer

University of Pittsburgh



November 6, 2008

Digital

repository

systems

represent

an

important

option

for

learning

organizations

that

want

to

leverage

the

economical

and

social

benefits

of

re
-
usable

learning

objects
.

The

presentation

examines

the

options

that

a

learning

organization

can

exercise

in

building

a

digital

repository

for

learning

objects,

identifying

both

open

source

and

proprietary

solutions,

assessing

select

systems

in

terms

of

functions,

features,

costs,

interoperability,

and

compatibility

with

relevant

technical

standards
.

Context

Web
-
Based Information Science Education



Web
-
based Information Science Education (WISE) is a groundbreaking
opportunity in online education, established under funding from ILMS and
now essentially self
-
sustaining.



Leading library and information science schools have extended their reach
on a global basis to broaden the educational opportunities available to
students. Led by Syracuse, Illinois, and Pittsburgh, WISE uses advanced
online technology to enrich education and foster relationships among
students, faculty, and universities.



The vision of this initiative is to provide a collaborative distance education
model that will increase the quality, access, and diversity of online
education opportunities in library and information science. Originally a
seat bank operating under an established exchange rate, WISE is now also
involved in developing new curricula across its member programs and in
association with various professional organizations.

The WISE+ Repository


Mandate to build a repository of learning objects
from a wide variety of courses offered in library
and information science


Based on preliminary data, most of the objects
are likely to take the form of
PDFs
, Word
documents, PowerPoint presentations, audio and
video recordings, i.e., *.mp3, *.
avi
, *.
mov
, *.
swf
,
etc., and HTML documents and Web sites


Objects developed without explicit mandate for
reusability or sharing

Key Concepts & Factors

Roles of Institutional Repositories


First: to "serve as tangible indicators of an institution's quality and
to demonstrate the scientific, societal, and economic relevance of
its research activities, thus increasing the institution's visibility,
status, and public value”


Second: to provide tools to assist universities "re
-
shape the
scholarly communication process”


Third: while institutional repositories centralize, preserve, and make
accessible an institution's intellectual capital, at the same time they
will


ideally


form part of a global system of distributed,
interoperable repositories that provides the foundation for a new
disaggregated model of scholarly publishing.


Raym

Crow,
The Case for Institutional Repositories: A SPARC Position
Paper
. The Scholarly Publishing & Academic Resources Coalition,
Washington, D.C., August 2002.

What are E
-
Learning Repositories?

An

E
-
Learning

repository

is

a

database

that

contains

useful

teaching

and

learning

information

that

is

available

via

the

Internet
.

Users

are

allowed

to

query

the

database

in

an

attempt

to

locate

information

that

can

help

to

explain

and

clarify

various

topics
.

Educational Content Standards


Besides open formats for general content and digital
formats there are also specific standards being developed
for describing educational content. Using these standards
can provide a basis for the creation of reusable content
across eLearning institutions and platforms.



The following are two metadata application profiles that
may be used to describe educational content:


The SCORM (Sharable Content Object Reference Model) is a
collection of specification and standards for web
-
based E
-
Learning Content packages.


The LOM (Learning Object Metadata) of the IEEE LTSC has the
goal to describe learning resources (digital and non
-
digital).


Sharable Content Object Reference Model (SCORM)

Sharable Content Object Reference Model (SCORM) is a collection of
standards and specifications for Web
-
based
e
-
learning. It defines
communications between client side content and a host system called the
run
-
time environment (commonly a function of a learning management
system). SCORM also defines how content may be packaged into a
transferable ZIP file.


SCORM is a specification of the Advanced Distributed Learning (ADL)
Initiative.


SCORM 2004 introduces a complex idea called sequencing, which is a set of
rules that specify the order in which a learner may experience content
objects. The standard uses XML, and it is based on the results of work done
by AICC (CBT), IMS Global, IEEE, and
Ariadne
.

Learning Object Metadata


Learning Object Metadata is a data model, usually encoded in
XML, used to describe a learning object and similar digital
resources used to support learning. The purpose of learning
object metadata is to support the reusability of learning objects,
to aid discoverability, and to facilitate their interoperability,
usually in the context of online learning management systems
(LMS).



The IEEE 1484.12.1


2002 Standard for Learning Object
Metadata is an internationally
-
recognized open standard for the
description of “learning objects”. Relevant attributes of learning
objects to be described include: type of object; author; owner;
terms of distribution; format; and pedagogical attributes, such as
teaching or interaction style.

Open Archives Initiative Protocol for Metadata
Harvesting (OAI
-
PMH)

The Open Archives Initiative Protocol for Metadata Harvesting (OAI
-
PMH) is a
low
-
barrier mechanism for repository interoperability. Data Providers are
repositories that expose structured metadata via OAI
-
PMH. Service Providers
then make OAI
-
PMH service requests to harvest that metadata. OAI
-
PMH is a
set of six verbs or services that are invoked within HTTP.


OAI
-
PMH is based on a client
-
server architecture, in which "harvesters"
request information on updated records from "repositories". Requests for
data can be based on a
datestamp

range, and can be restricted to named sets
defined by the provider. Data providers are required to provide XML metadata
in Dublin Core format, and may also provide it in other XML formats.


A number of software systems support the OAI
-
PMH, including
EPrints
, Open
Journal Systems from the Public Knowledge Project, Desire2Learn,
DSpace

and
HyperJournal

from the University of Pisa.

Meta Encoding and Transmission Standard

The METS schema is a standard for encoding
descriptive, administrative, and structural
metadata regarding objects within a digital
library, expressed using the XML schema
language of the World Wide Web Consortium.
The standard is maintained in the Network
Development and MARC Standards Office of the
Library of Congress, and is being developed as an
initiative of the Digital Library Federation.

Re
-
Usable Learning Objects

Chiappe

defined

learning

objects

as
:

"A

digital

self
-
contained

and

reusable

entity,

with

a

clear

educational

purpose,

with

at

least

three

internal

and

editable

components
:

content,

learning

activities

and

elements

of

context
.

The

learning

objects

must

have

an

external

structure

of

information

to

facilitate

their

identification,

storage

and

retrieval
:

the

metadata
.

"

Chiappe
,

Andres
.;

Segovia,

Yasbley
;

Rincon,

Yadira

(
2007
),

"Toward

an

instructional

design

model

based

on

learning

objects"

(html),

in

Boston,

Springer,

Educational

Technology

Research

and

Development
,

Boston
:

Springer,

pp
.

671
-
681
.


Rehak

and

Mason

define

it

as

"a

digitized

entity

which

can

be

used,

reused

or

referenced

during

technology

supported

learning”
.

Rehak
,

Daniel

R
.;

Mason,

Robin

(
2003
),

"Engaging

with

the

Learning

Object

Economy",

in

Littlejohn,

Allison,

Reusing

Online

Resources
:

A

Sustainable

Approach

to

E
-
Learning
,

London
:

Kogan

Page,

pp
.

22
-
30
.



Re
-
Usable Learning Objects,
con’t

Learning

objects

are

a

new

way

of

thinking

about

learning

content
.

Traditionally,

content

comes

in

a

several

hour

chunk
.

Learning

objects

are

much

smaller

units

of

learning,

typically

ranging

from

2

minutes

to

15

minutes
.

There

is

a

general

consensus

that

learning

objects

should

be
:



self contained



reusable
-

can be modified and versioned for different
courses



accessible
-

indexed and retrieved using metadata



interoperable / portable
-

operate across different
hard/software



durable
-

remain intact across upgrades of
hard/software



capable of aggregation



Reviewing Key Digital Repository
Software Packages

Basic Choices, Key Variables

BePress

ContentDM

Fedora (as Developed by Cornell and University
of Virginia)

Fedora’s Object Model

Fedora Repository Model

Muradora

Interface for Fedora

Fedora Entry via
Muradora

Interface

Islandora

Fedora
-
Drupal

module

The
Islandora

module allows
Drupal

users to view and
manage digital objects stored in Fedora. There is a demo
Amazon ec2 image running here
http://ec2
-
75
-
101
-
195
-
219.compute
-
1.amazonaws.com/
.
Drupal

and Fedora are
installed. If you have an Amazon AWS account you can
launch your own version of the image. The public image
name is
ami
-
e9d23680
.


Once the image is started you will have to login to the newly
created image using
ssh

and start Fedora. You will then be
able to use a browser to view your new AMI instance by
browsing to the system’s public DNS address.

Islandora

SIDEBAR: the Virtues of Cloud Computing


Capital expenditure minimized and thus low barrier to entry as
infrastructure is owned by the provider and does not need to be
purchased for one
-
time or infrequent intensive computing tasks.


Device and location independence which enables users to access systems
regardless of location or what device they are using.


Multi
-
tenancy enabling sharing of resources (and costs)


Reliability by way of multiple redundant sites, which makes it suitable for
business continuity and disaster recovery.


Scalability which meets changing user demands (e.g. Flash Crowds)
quickly, without having to engineer for peak loads.


Security typically improved due to centralization of data, increased
security
-
focused resources, etc.


Sustainability through improved resource utilization, more efficient
systems and carbon neutrality.


Basic
Cloud Computing
Configuration

SIDEBAR 2: the Virtues of Embedding the
Repository in a CMS


Contextualization


Access to collaborative resources & services
within the same platform, including
documentation, modules,
plugins
, etc.


Ability to leverage resources of surrounding
development communities (in the instances of
popular, open source
CMSs

such as
Drupal
,
Joomla
, or
Plone
)

EPrints

EPrints

is

an

open

source

software

package

for

building

open

access

repositories

that

are

compliant

with

the

Open

Archives

Initiative

Protocol

for

Metadata

Harvesting
.

It

shares

many

of

the

features

commonly

seen

in

document

management

systems,

but

is

primarily

used

for

institutional

repositories

and

scientific

journals
.

EPrints

has

been

developed

since

2000

at

the

University

of

Southampton

and

released

under

a

GPL

license
.


EPrints

Technology

EPrints

is a Web and command
-
line application based on the
LAMP

architecture (but is written in Perl rather than PHP). It has been
successfully run under Linux, Solaris and Mac OS X. A version for
Microsoft Windows is being developed but will be released under a non
-
GPL license. Version 3 of the software introduced a (Perl
-
based)
plugin

architecture for importing and exporting data, converting objects (for
search engine indexing) and user interface widgets.


Configuring an
EPrints

repository involves modifying configuration files
written in Perl or XML. Web based configuration tools are in
development. The appearance of a repository is controlled by HTML
templates,
stylesheets

and inline images. While
EPrints

is shipped with
an English translation it has been translated to other languages through
(redistributable) language
-
specific XML phrase files. Existing translations
include Bulgarian, French, German, Hungarian, Italian, Japanese, Russian,
Spanish and Ukrainian

Opening Screen for
EPrints

Short Record, Abstract & Object Link
under
EPrints

Metadata Form/Scheme as Part of the
EPrints

Entry Form

Logging/User History for
EPrints

DSpace

Developed co
-
operatively by Hewlett
-
Packard and MIT. The first
version of
DSpace

was released in November 2002. In 2007, HP
and MIT jointly announced the formation of the
DSpace

Foundation, a non
-
profit organization that will provide
leadership and support for the
DSpace

community.


DSpace

is written in Java and JSP, using the Java
Servlet

API. It
uses a relational database, and supports the use of
PostgreSQL

and Oracle. It makes its holdings available primarily via a web
interface, but it also supports the OAI
-
PMH v2.0, and is capable
of exporting METS (Metadata Encoding and Transmission
Standard) packages. The
DSpace

community has attempted to
base its formal structure along the same lines as the Apache
Foundation community development model.

DSpace

Using the
Manakin

UI

Default view of a
DSpace

instance established
as part of learning laboratory

Short Entry in
DSpace

Item Submission Form in
DSpace

Selecting a Digital Repository

Key Factors & Considerations

Why We Selected
DSpace


Strong commitment to ongoing development


Easy to install & maintain; stable under
significant demand


Tomcat is easy to manage;
Eprints

reliance on
mod_perl

makes it difficult to configure


Portable/will run successfully on various Oss;
upgrade path is well
-
designed


Customizable metadata


Flexible workflow model

A content management system and blog were included in order
to provide facilities supporting the preparation and delivery of
documentation, collaborative work, discussion forums, and other
forms of resource sharing. The blog was created to support end
-
user communications and solicit comments, but will probably be
phased out owing to the availability of similar capabilities
available through the CMS.

Creating a Peer Review Ratings System


Building on the Evaluation Criteria Developed by/for MERLOT


Quality of Content


Potential Usefulness as a Teaching/Learning Tool


Ease of Use


Institute an Interactive Ratings System


If We Knew Then What We Know Now …..

….. would probably take a much longer look at
the system

PEIU’s
Islandora

--
which integrates
Fedora into
Drupal

…… explore the possibility of building the
repository behind the
eduCommons

platform

…… spend more time on establishing guidelines
for the development of genuinely
shareable/usable learning objects


44

The End