Interoperable metadata for a federation of learning repositories on organic agriculture and agroecology N. Palavitsinis, K. Kastrantas and N. Manouselis Greek Research & Technology Network, 56, Mesogion Av. 11527, Athens, Greece; [email protected]; kkastradgrnet.gr; palavitsinisgrnet.gr Abstract Metadata plays an important role in online repositories with learning resources, since it can make search, retrieval and access faster, easier and more effective. In this context, a variety of reasons urge using a recognized metadata standard such as IEEE Learning Object Metadata (LOM). When particularly developing a repository with learning resources for agricultural stakeholders, it is important to take into consideration the variety of special requirements that have to be reflected in the metadata (e.g. linguistic preferences, geographical location, particularity of covered topics, educational level). This calls for the implementation of both standard-based and also contextspecialized educational metadata in such repositories. In this direction, the present paper describes the metadata schema that has been developed to support an online repository that stores learning resources on Organic Agriculture (OA) and Agroecology (AE). Keywords: learning object, metadata, application profile, portal Introduction Metadata is usually termed as ‘data about data’ or ‘information about information’ (NISO, 2004; Steinacker et al., 2001). It is generally engaged for describing the properties of information resources, in order to facilitate their categorization, storage, search and retrieval in digital collections. If metadata is stored in a structured and standardized manner, it may generally support the automation of search and retrieval mechanisms, the comparison between descriptions of different resources, the reusability of descriptions in different applications, as well as the interoperability between different storage systems. Metadata is made up of data items that are associated to the resource, the so called metadata elements. Metadata schemas (or metadata models) are sets of metadata elements designed for a specific purpose, such as describing a particular type of resource (NISO, 2004). Metadata specifications are well-defined and widely agreed metadata schemas that are expected to be adopted by the majority of implementers in a particular domain or industry. When a specification is widely recognized and adopted by some standardization organization (such as ISO – the International Standardization Organization), it then becomes a metadata standard. There is no one all-encompassing metadata standard to be used in all applications. Rather, there are various metadata standards or specifications that can be adapted or ‘profiled’ to meet community context-specific needs (Kraan, 2003)). This conclusion has lead to the emergence of the application profile concept. An application profile is an assemblage of metadata elements selected from one or more metadata schemas, and its purpose is to adapt or combine existing schemas into a package that is tailored to the functional requirements of a particular application, while retaining interoperability with the original base schemas (Duval et al., 2002). One area of particular interest for metadata development is the one of digital learning repositories (DLRs). These are online databases in which digital learning resources are systematically organized,

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classified and published. Many institutions are currently engaged in developing DLRs that can be searchable and accessible from a wide audience (Tzikopoulos et al., 2007). Metadata play an important role in DLRs, since they help searching, finding and organizing learning resources. Towards this direction, standardization efforts around the world such as the IEEE Learning Technology Standards Committee (IEEE LTSC, http://ieeeltsc.org/) and ISO’s sub-committee on ‘Information Technology for Learning, Education and Training (ITLET)’ (ISO/IEC JTC1 SC36, http://jtc1sc36.org/) have focused on the implementation of the IEEE Learning Object Metadata (LOM) standard (IEEE-LOM, 2002; ISO/IEC, 2005). Using such a recognized metadata standard is important for a variety of reasons: metadata descriptions (records) of learning resources may be exchanged among different DLRs; search queries may be propagated among different (and interconnected) DLRs; and generally the integration of data from different sources is facilitated. This is the reason behind the extensive implementation and study of numerous application profiles of the LOM standard in DLRs around the world (Tzikopoulos et al., 2007). When particularly developing a DLR for agricultural stakeholders, an important aspect is to take into consideration the fact that resources for such learners have to reflect and match a variety of special requirements (e.g. linguistic preferences, regional geographical coverage, particularity of covered topics, and educational level of addressed audience). This calls for the development of standard-based, but also context-specialized educational metadata. In this paper we discuss our experience from developing such a metadata schema in the context of a portal on subjects of Organic Agriculture (OA) and Agroecology (AE) that aims to address the lifelong learning needs of agricultural stakeholders. More specifically, the proposed metadata schema is a LOM application profile that is being implemented in a federation of digital learning repositories with digital learning objects for agricultural stakeholders. Background The use of commonly accepted agricultural metadata schemas aims to make it easier to integrate data from different sources, allowing for creation of value added services for the agricultural sector. A variety of metadata schemas have already been proposed and used in the context of agricultural applications (Manouselis et al., 2007). Efforts are being made to make relevant initiatives around the world to join forces, and to coordinate the further involvement of interested stakeholders. This is the vision of clusters such as the Agricultural Information Management Standards (AIMS) of the Food and Agriculture Organization of the United Nations (FAO). An application area, that has attracted increased interest by agricultural stakeholders, is the one of educational metadata. There have been several interesting approaches regarding the implementation of educational metadata schemas that will describe learning resources for agricultural stakeholders. A main strand of these approaches includes the ones that are developing application profiles of the IEEE LOM standard. For instance, the CG LOM Core (CGIAR, 2005) has been created by the Consultative Group on International Agricultural Research (CGIAR) in order to describe its learning resources in a manner that best suits the content, purpose and audience of CGIAR’s Online Learning Resources project (http://learning.cgiar.org/). This involves the development of a DLR that will support an international community of trainers, educators, researchers and learners in agriculture and natural resources management. CGIAR defined a core set of metadata elements, which describe, document and register the CG learning object metadata core (which is termed as CG LOM Core). The goal of applying a shared set of core metadata elements is to allow the federated search of training related documents across all CGIAR centers, as well as to achieve interoperability across the centers and with external entities. Because most Centers have based the metadata of their Web

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resources on the internationally recognized Dublin Core (DC, 2004) format, the CG LOM core also includes a mapping with the DC metadata element set. Another interesting LOM application profile is the one that has been developed by the European e-Content project 11293 ‘Bio@gro’ for information dissemination and public awareness increase regarding organic agriculture (http://bioagro.aua.gr). This was created in order to categorize online educational resources that are related to Organic Agriculture topics (Bio@gro, 2005). The Bio@ gro LOM application profile has adopted a number of LOM elements, appropriately selecting vocabularies of values in such a way that the metadata descriptions reflect the particularities of the application area (organic agriculture). It will be also used as a basis for the development of a revised application profile for the description of learning resources for OA & AE (Sanchez-Alonso and Sicilia, 2007). Another approach, which is developing an application profile mostly based on Dublic Core, is the Agricultural Learning Resources Application Profile (Ag-LR AP) that is developed by FAO (Stuempel et al., 2007). This schema supports FAO’s Capacity and Institution Building Portal, which provides structured access to information on FAO’s capacity and institution building services and learning resources. It aims to ensure that this portal can be searched by users and that interoperability with other educational repositories is enabled. Since the listed learning resources were already described using the AGRIS application profile1, (which is based on DC), it has been chosen to base the Ag-LR AP to DC, also borrowing selected elements from LOM. Other relevant application profiles of metadata for agricultural DLRs are reviewed and classified in a recent study (Manouselis et al., accepted for publication). The Organic.Edunet application profile In the context of the Organic.Edunet initiative (http://www.organic-edunet.eu/organic/index.html), a network of DLRs with learning resources on Organic Agriculture (OA) and Agroecology (AE) is being developed. The repositories will allow users to search, locate and access these learning resources through an online multilingual environment. This requires the development of an appropriate metadata schema that will implemented to support the repository functionalities. For the description and classification of the digital learning objects (LOs), an application profile of the IEEE LOM standard was developed. More specifically, the Organic.Edunet Application Profile is proposed. Organic.Edunet digital learning objects Through the use of the Organic.Edunet AP, the Organic.Edunet project aims to facilitate access, usage and exploitation of digital educational content related to OA & AE. It will deploy a multilingual online federation of learning repositories, populated with quality content from various content producers. In addition, it will deploy a multilingual online environment (the Organic.Edunet Web portal) that will facilitate end-users’ search, retrieval, access and use of the content in the learning repositories. The project will study educational scenarios that introduce the use of the Organic. Edunet portal and content to support teaching of topics related to OA & AE in two cases of formal educational systems, i.e. high-schools and agricultural universities. Furthermore, it will evaluate project results in the context of pilot demonstrators in pilot educational institutions, as well as through open validation events where external interested stakeholders will be invited. Organic. Edunet focuses on achieving interoperability between the digital collections of OA & AE content 1 

http://www.fao.org/docrep/008/ae909e/ae909e00.htm.

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that producers in various EU countries have developed, as well as facilitating publication, access, and use of this content in multilingual learning contexts through a single European reference point. In this way, digital content that can be used to educate European Youth about the benefits of OA & AE, will become easily accessible, usable and exploitable. Elements As explained earlier, the IEEE LOM standard has been chosen as the basis for the metadata application profile to be used in Organic.Edunet’s AP. The schema is therefore termed as Organic. Edunet application profile. It adopts many of the elements of LOM, specializing several of them in order to best match the needs of the particular LOs. In the next paragraph, we will go through the nine (9) categories of elements of LOM, referring to the elements used, and presenting the performed specializations. Some of the specializations are adopted from the Learning Resource Exchange (LRE) AP v3.0 (http://fire.eun.org/LRE-AP-3.0.pdf). The first category of LOM elements is the General one. It includes elements that describe a learning object (in our case, a LO), and store general information about it. In Organic.Edunet AP, the following elements have been selected for use as recommended by LOM: ID, Title, Language, Description, Keyword, Structure and Aggregation Level. In addition, element Coverage have been specialized as it is presented in Table 1. The next category Life Cycle describes the history and current state of a LO, as well as the entities that have affected the LO during its evolution. In Organic.Edunet AP, the following elements have been selected and used as recommended by LOM: Version, Status, and Contribute. The Meta-Metadata category contains information about the metadata record that describes the LO. It identifies the metadata record in a classification system (i.e. the repository’s database with the metadata descriptions). It contains information about who provided the LO description and when, which metadata schema was followed to produce the metadata description, and in which language the metadata are in (which can be different than the language of the learning object itself). In Organic.Edunet AP it is used as recommended by LOM, and includes the elements: ID, Metadata Scheme, Language and their designated sub-elements. As far as the Contribute element is concerned, the LOM vocabulary used is enriched with the roles of enricher and provider. The respective terms are defined in the LREv3.0 vocabulary. In a similar manner, a set of selected items from the Technical category are used to describe the technical requirements and characteristics of a LO. The elements selected for Organic.Edunet AP are: Format, Size, Location, Other Platform Requirements, and Duration. The Educational category describes the key educational or pedagogic characteristics of a LO. In Organic.Edunet AP, the following elements have been selected for use with the vocabulary values

Table 1. Elements of the General category that have been further specialized in Organic.Edunet AP. Element

Sub-element Description

General

Coverage

878

Use in Organic. Edunet

The time, culture, Include coverage of geography or specific European region to which regions. this learning object applies.

Vocabulary

LRE Thesauri ‘160. Countries and Geopolitical Areas’

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Table 2. Elements of the Meta-Metadata category that have been further specialized in Organic. Edunet AP. Element

Sub-element Description

MetaContribute. Metadata Role

Use in Organic. Edunet

Kind of contribution. Enriched vocabulary Exactly one instance containing more of this data element values than LOM with value Creator should exist.

Vocabulary

Enriched by adopting LREv3.0

that LOM specifies: Interactivity Type, Interactivity Level, Typical Age Range, Difficulty, and Typical Learning Time. In addition, elements Learning Resource Type, Intended End User Role and Context have been specialized as presented in Table 3. The Rights category describes the intellectual property rights and conditions of use for this LO. In Organic.Edunet AP it is used as recommended by LOM, and includes the elements: Cost, Copyright & Other Restrictions, and Description. There has been an addition to the values of the element Description with the introduction of Creative Commons licenses in order to describe the copyrights and other restrictions. Extended information on the vocabulary values can be obtained in the relevant documentation of the Organic.Edunet AP. In the Relation category that defines the relationship between the described LO and other LOs, all LOM-specified elements are used: Kind, Resource, Purpose and their designated sub-elements. As far as the Kind element is concerned, the LOM vocabulary used is replaced with the respective terms defined in the LREv3.0 vocabulary.

Table 3. Elements of the Educational category that have been further specialized in Organic. Edunet AP. Element

Sub-element Description

Educational Learning Resource Type

Use in Organic.Edunet Vocabulary

Specific kind of learning Adopted a different object. The most vocabulary than dominant kind shall LOMv1.0 be first. Intended End Principal user(s) for Enriched vocabulary User Role which this LO was containing more designed, most values than LOM dominant first. Context The principal Enriched vocabulary environment within containing more which the LO and use values than LOM of this LO is intended to take place.

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Adopted from LREv3.0

Adopted from LREv3.0

Adopted from LREv3.0

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Table 4. Elements of the Rights category that have been further specialized in Organic.Edunet AP. Element

Sub-element Description

Rights

Description

Use in Organic. Edunet

Vocabulary

Whether copyright Creative Commons or other restrictions adopted to describe apply to the use of copyrighted material this learning object.

‘x-t-cc-url’, ‘http:// creativecommons. org /licenses/bysa/3.0/’

The Annotation category provides comments on the educational use of a LO, and information on when and by whom the comments were created. This category enables educators (trainers) to share their assessments of LOs, suggestions for use, etc. In Organic.Edunet AP, all LOM-specified elements are used: Entity, Date, and Description. There is a significant difference for the Description sub-element as far as the IEEE LOM standard is concerned since the Organic.Edunet project has developed and imposed its own quality assurance procedures. In this way, the description subelement has it’s own vocabulary values that more or less, restrict the freetext description of the LOM standard.

Table 5. Elements of the Relation category that have been further specialized in Organic.Edunet AP. Element

Sub-element Description

Relation

Kind

Use in Organic.Edunet Vocabulary

Nature of the Enriched vocabulary relationship between containing more this learning object values than LOM and the target learning object

Adopted from LREv3.0

Table 6. Elements of the Annotation category that have been further specialized in Organic. Edunet AP. Element

Sub-element Description

Annotation Description

880

Use in Organic. Edunet

The content of the Quality mark of annotation for each each collection / element. provider Internal quality review report

Vocabulary

‘Quality certified from X provider’ Results from internal quality control procedure

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Finally, the Classification category describes where this LO falls within a particular classification system. All the elements described in LOM are used in Organic.Edunet AP. In the context of Organic. Edunet initiative, a new classification system was introduced namely the Organic.Edunet ontology which is used as a possible value in the sub-element Source along with other classification systems such as AGROVOC Thesaurus2, CAB Thesaurus3 and LRE Thesauri4.

Table 7. Elements of the Classification category that have been further specialized in Organic. Edunet AP. Element

Subelement

Classification Entry

Description

Use in Organic. Edunet

Vocabulary

The textual label of the taxon used.

Classification using ‘Organic Farming’; the Organic.Edunet ‘Fruit production’ ontology Classification using ‘Environmental the AGROVOC pollution’, Thesaurus ‘Environmental contamination’ Classification ‘environmental using the CABI science’, ‘animal Classification health’ Classification ‘environmental using the LRE education’, ‘ecology’ Microthesauri

Example of use In Table 8, we provide an example description of a LO regarding insect pest management control for organic crops. Due to space restrictions, not all elements are used. Instead of that, we are restricted only to a selection of all the mandatory and the most common recommended elements of the AP. Conclusions The development of an appropriate metadata schema can greatly facilitate the search and retrieval tasks of the users that are accessing an online DLR. In addition, the adoption of a well-accepted metadata standard (such as LOM), can promote interoperability between the Organic.Edunet repository and others, as well as reusability of the metadata records. On the other hand, in repositories for agricultural stakeholders, the adopted metadata schema has to be appropriately contextualized in order to better meet user needs and requirements. In this paper we present such a specialization

ftp://ftp.fao.org/gi/gil/gilws/aims/references/flyers/agrovoc_en.pdf and www.fao.org/agrovoc/. http://www.cabi.org/DatabaseSearchTools.asp?PID=277. 4  http://insight.eun.org/intern/shared/data/insight/lre/AppProfilev3p0.pdf. 2  3 

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Table 8. Example of a Organic.Edunet AP metadata record.. Element

Value

1. General 1.2 Title 1.3 Language 1.4 Description 1.5 Keyword 1.6 Coverage 1.7 Structure 2. Life Cycle 2.3 Contribute

Insect Pest Management for Organic Crops en Analytical instructions about how to deal with the pest problem in the case of Organic Crops Organic Crops, Pest Management, Incect America, Africa, Europe collection 2.3.1 Role 2.3.2 Entity

2.3.3 Date 4. Technical 4.1 Format 4.2 Size 4.3 Location 5. Educational 5.2 Learning Resource Type 5.5 Intended End User Role 5.6 Context 5.7 Typical Age Range 6. Rights 6.1 Cost 6.2 Copyright and Other Restrictions 6.3 Description 9. Classification 9.2 Taxon Path 9.2.1 Source 9.2.2 Taxon 9.2.2.1 Id 9.2.2.2 Entry 9.3 Description 9.4 Keyword

publisher University of California, Division of Agriculture and Natural Resources 2000 text/ pdf 90600 bytes http://anrcatalog.ucdavis.edu/pdf/7251.pdf learning asset/ text author, learner, teacher higher education, professional development 18-U No Yes Attribution Non-commercial Share Alike (by-nc-sa) OrganicEdunet Ontology Biological Pest Control Pest Management, Ecological Pest Control

termed Organic.Edunet Application Profile, a LOM application profile for the Organic.Edunet project. Using the IEEE LOM standard is in line with the majority of other efforts deploying similar repositories of learning objects (Tzikopoulos et al., 2007). Nevertheless, large repositories such as the ones of FAO include metadata records that are based on Dublin Core (Stuempel et al., 2007). Therefore, further effort is required in order to come closer with different approaches, by developing jointly accepted mappings between developed schemas, as well as categorizing resources according to a recognized thesaurus such as FAO’s AGROVOC (Sanchez-Alonso and Sicilia, 2007).

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Acknowledgment The work presented in this paper has been funded with support by the European Commission, and more specifically the project ECP-2006-EDU-410012 ‘Organic.Edunet: A Multilingual Federation of Learning Repositories with Quality Content for the Awareness and Education of European Youth about Organic Agriculture and Agroecology’ of the eContentPlus Programme. References Bio@gro, ‘Metadata Models for Bio@gro Content Objects (BCOs) Description’, Bio@gro Technical Report, 2005 (available from the authors). CGIAR, ‘CG Learning Object Metadata (LOM) Core’, Thomas Zschocke, Courtney Paisley, Erik Duval and Jan Beniest, ICT/KM OLR Project November 2005. DC, ‘Dublin Core Metadata Element Set, Version 1.1: Reference Description’, Dublin Core Org., 2004. Duval E., Hodgins W., Sutton S., Weibel S.L., ‘Metadata Principles and Practicalities’, D-Lib Magazine, 8, 2002. IEEE LOM, ‘Draft Standard for Learning Object Metadata’, IEEE Learning Technology Standards Committee, IEEE 1484.12.1-2002, 15 July 2002. ISO/IEC, ‘Working Draft for ISO/IEC 19788-2 – Metadata for Learning Resources – Part 2: Data Elements’, ISO/IEC JTC1 SC36, 2005. Kraan W., ‘No one standard will suit all’, The Centre for Educational Technology Interoperability Standards, Presentation available online, 2003. (http://www.cetis.ac.uk/content/20030513175232). N. Manouselis, K. Kastrantas and A. Tzikopoulos, ‘An IEEE LOM application profile to describe training resources for agricultural & rural SMEs’, in the Proc. of the 2nd International Conference on Metadata and Semantics Research (MTSR’’07), Corfu, Greece, October 2007 N. Manouselis, J. Najjar, K. Kastrantas, G. Salokhe, C.M. Stracke, E. Duval, ‘Metadata Interoperability in Agricultural Learning Repositories’, Computers and Electronics in Agriculture, Special Issue on Information and Communication Technologies in Biological and Earth Sciences, Elsevier (accepted for publication). NISO, ‘Understanding Metadata’, National Information Standards Organisation, NISO Press, 2004. Sanchez-Alonso S., Sicilia M.-A., ‘Using an AGROVOC-based ontology for the description of learning resources on organic agriculture’, in the Proc. of the 2nd International Conference on Metadata and Semantics Research (MTSR’07), Corfu, Greece, October 11-12, 2007. Steinacker A., Ghavam A., Steinmetz R., ‘Metadata Standards for Web-Based Resources’, IEEE Multimedia, January-March, 70-76, 2001. Stuempel H., Salokhe G., Aubert A., Keizer J., Nadeau A., Katz S., Rudgard S., ‘Metadata Application Profile for Agricultural Learning Resources’, in the Proc. of the 2nd International Conference on Metadata and Semantics Research (MTSR’07), Corfu, Greece, October 11-12, 2007. Tzikopoulos A., Manouselis N., Vuorikari R., ‘An Overview of Learning Object Repositories’, in P. Northrup (Ed.) Learning Objects for Instruction: Design and Evaluation, Hershey, PA: Idea Group Publishing, 2955, April 2007.

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