Digital Preservation Metadata And Standardization

Published Date: 02 Nov 2017

Growing of information and telecommunication technologies, web technologies and database technologies has compelled library and information centers to use these technologies effectively and preserve it. World Wide Web affords unprecedented access to globally distributed information. Information technological innovations with its awareness are delimited by the degree of difficulty involved in acquiring access to information. It depends upon both ease of use metadata strategy. Metadata improves discovery and access of such information. Metadata is an increasingly central tool in the current web environment, enabling large-scale, distributed management of resources. Recent years has seen a growth in interaction between previously relatively isolated metadata communities, driven by a need for cross-domain collaboration and exchange. However, metadata standards have not been able to meet the needs of interoperability between independent standardization communities. For this reason the notion of metadata harmonization, defined as interoperability of combinations of metadata specifications, has risen as a core issue for the future of web-based metadata. A set of widely used metadata specifications in the domains of learning technology, libraries and the general web environment have been chosen as targets for the analysis, with a special focus on Dublin Core, IEEE LOM and RDF. Through active participation in several metadata standardization communities, a body of knowledge of harmonization issues has been developed Abstract models for metadata as a tool for designing metadata standards.

Keywords

Digital Preservation, Metadata, Types of Metadata Standard

Introduction:-

Today digital technology is enabling to information found.

The purpose of preservation is to ensure protection of information of enduring values for access by present and future generation. We are transition period from traditional library convert to digital library environment.

Metadata is the backbone of digital curation. Without it a digital resource may be irretrievable, unidentifiable or unusable. Metadata is descriptive or contextual information which refers to or is associated with another object or resource. This usually takes the form of a structured set of elements which describe the information resource and assists in the identification, location and retrieval of it by users, while facilitating content and access management.

2. What do you mean by Digital Preservation?

Digital preservation means taking step to ensure the longevity of electronic documents. It applies to document that are either "born digital" and stored on-line or to the product of analog- to- digital conversion.

2.1. Necessity of digital preservation:

Today more and more information is created in digital form, either through converting existing materials to digital form.

There are increasing expectations in all spheres of life that the information we all need will be available on the internet or offline digital format e.g. CD-ROM.

Digital access has many benefits over the paper-based or microform access in terms of convenience and functionality.

The increasing proliferation of digital information combined with the considerable challenges associated with ensuring continued access to digital information.

3. What is Metadata?

Metadata is " Information about information" Metadata structured information that describes retrieval for managing information resource. Metadata describe data elements and their attributes such as name, size, data type and also data structures etc. Metadata describe specific characteristics, which provides guidelines with standard format. The information may include Name, Ownership, Description, Currency, Status, Quality, Contact details etc.

3.1. How create Metadata?

To encode information the data should be expressed in proper way. Create a single disk file for each Metadata record, that is one disk file describe one data set. Then use some tool to enter information into this disk file so that metadata confirm to the standard.

3.2. Purpose of Metadata

Purpose of Metadata is expressed as information retrieval management of information services, documenting ownership and authenticity, interoperability.

Metadata helps in management of various information services like OPAC, SDI etc.

It is a vehicle for documenting owner ship authenticity of the information.

Resource description, Record of Intellectual property Right, Documenting software and hardware environment, Resource Discovery, Preservation Management of Digital Resources.

3.3. Types of Metadata Standard

Metadata is made up of a number of elements which can be categorized into the different functions they support. A metadata standard will normally support a number of defined functions, and will specify elements, which make these possible. A metadata standard may support some or all of the following functions:

Descriptive Metadata enables identification, location and retrieval of information resources by users, often including the use of controlled vocabularies for classification and indexing and links to related resources.

Technical Metadata describes the technical processes used to produce, or required to use a digital object.

Administrative Metadata is used to manage administrative aspects of the digital object such as intellectual property rights and acquisition. Administrative Metadata also documents information concerning the creation, alteration and version control of the metadata itself. This is sometimes known as meta-metadata!

Use Metadata manages user access, user tracking and multi-versioning information.

Preservation Metadata, amongst other things, documents actions which have been undertaken to preserve a digital resource such as migrations and checksum calculations.

4. METADATA STANDARDIZATION

The Dublin Core set of specifications, popular on the World Wide Web and in the digital library community. The Resource Description Framework, RDF, a W3C specification for web-enabled meta-data.

MPEG-7, a complex metadata standard for digital video;

A set of library related standards: MODS, an XML encoding of parts of the de facto library metadata standard MARC; METS, a metadata container format; and Resource

Description and Access, the new library cataloging standard.

A number of specifications from the IMS Global Learning Consortium, such as IMS Metadata, IMS Content Packaging, IMS Question and Test Interoperability and IMS Learner Information Package that have metadata parts.

Additionally, a number of metadata standards and specifications that are based on one of the above are also relevant. Based on Dublin Core are for example EdNA, a metadata standard for the Australian Education Network, and GEM, a US government-sponsored Gateway to Educational Materials. Based on LOM we find among many others the RDN/LTSN LOM application profile (RLLOMAP) and the Curriculum Online Metadata Schema. The IMS metadata standard and SCORM also reuse LOM as a basis on top of which they build their own frameworks.

These various standards and specifications have been developed to meet different requirements ,and to support the needs of different communities. In some cases the standards reflect the broadly shared requirements of a large community; in others, they reflect more specific requirements of a smaller or more specialized community, perhaps defined by activity/interest or by geopolitical boundaries.

The development and usage of these specifications has highlighted the necessity of being able to use component parts of different standards in combination . in other words, the importance of metadata harmonization. Because these standards are not designed to be compatible, they have been a fruitful focus of the harmonization research of this thesis.

4.1. The Library Metadata Standards: MODS, METS, RDA

In the field of library metadata, the dominant standard for bibliographic information has long

been the arcane MARC format, with roots in the 1960s. The MARC standard with its peculiarities and not very machine-friendly format is unsuitable as a basis for metadata harmonization . Several approaches for addressing this problem have been developed.

MARC-XML16 is a direct XML translation of MARC designed as a stepping stone between

MARC and other metadata formats. It retains all of the MARC structure, semantics and data types, but uses an XML syntax. While it improves dramatically on the machine processability of the MARC format, many of the core problems of MARC metadata still remain.

The Metadata Object Description Schema (MODS)17 format has been developed by the Library

of Congress to serve as a modern version of the MARC format. It is designed using XML technology and conventions, which makes it a more interesting object for harmonization efforts.

MODS can be used in conjunction with the Metadata Encoding and Transmission Standard

(METS)18, which essentially is an XML-based container format for bibliographic metadata,

Designed to provide metadata about bibliographic records in a multitude of formats.

However, the most interesting development in the library domain is most certainly the Resource

5. Examples of Metadata Standards

There are a large number of metadata standards, which address the needs of particular user communities. The first three profiled below primarily support discovery and access. They are progressively more complex to implement and more specialized to particular domains. The last, PREMIS, has been developed specifically to support digital preservation activities.

5.1. Dublin Core Metadata Element Set

The Dublin Core Metadata Element Set (ISO Standard 15836) is a basic standard which can be easily understood and implemented and as such is one of the best known metadata standards. It was originally developed, in 1995, as a core set of elements for describing the content of web pages and enabling their search and retrieval. The Dublin Core Metadata Element Set consists of 15 elements which address the most basic descriptive, administrative and technical elements required to uniquely identify a digital resource. The emphasis is now on supporting resource discovery across domains. The Dublin Core Metadata Initiative develops and maintains a suite of inter-related standards. It coordinates a number of working groups who collaborate to develop a metadata registry which supports extended and qualified profiles of Dublin Core, tailored to the needs of a number of different communities or functions, e.g. Dublin Core Collection Description Application Profile (for describing whole collections) and Dublin Core Library Application Profile (for describing published library holdings). Most resource discovery metadata standards can be mapped to the Dublin Core Metadata Element Set, enabling basic federated searching across metadata created using a number of different standards, without detracting from richer metadata held elsewhere. A draft specification for expressing Dublin Core in XML is available from the Dublin Core Metadata Initiative.

5.2. e-GMS (e-Government Metadata Standard)

The UK Government is committed to enabling consistency across public sector information and providing better access to public services. As part of this commitment they have developed e-GMS, a metadata standard for government information resources, to enable consistency across government and public sector organisations. Its use is compulsory within the sector and is part of the wider e-GIF (the e-Government Interoperability Framework) which defines technical policies and specifications to enable interoperability and easy access to information across the sector. The standard is currently at version 3 (2004) although version 3.1 will be released soon and a complete overhaul to version 4 is planned. The 15 elements of Dublin Core makes up the core of the standard and it can be readily mapped to 5 other standards if interoperability across metadata records from other disciplines is required. The further 10 elements take account of records management functions, Data Protection and Freedom of Information legislation and basic preservation information. A cut down version of the standard, e-GMS for websites (currently at version 3), is available for those creating metadata for websites.

5.3. ISO 19115: 2003(E) — Geographic Information: Metadata

ISO 19115 was developed by the geospatial community to address specific issues relating to both the description and the curation of spatial data. This complex metadata standard can be used for describing digital or physical objects or datasets which have a spatial dimension. There are over 400 elements in the Data Dictionary, which are divided into 14 metadata packages. Each package supports a particular function, some are specific to spatial data and some deal with general description and data curation issues. Abstract models written in UML (Unified Modeling Language) are provided for most of the packages to help the implementer understand how the elements interrelate. The standard also includes methodologies for creating application profiles, metadata extensions and hierarchical metadata and provides implementation examples. Geospatial professionals have developed a number of profiles of this standard to fit particular uses. One of these is UK GEMINI which defines an element set for discovery level metadata. It is also compliant with e-GMS and was developed collaboratively by the UK Association of Geographic Information (AGI) and the Cabinet Office e-Government Unit.

The accompanying XML schema, ISO/CD TS 19139 Geographic information — Metadata — XML schema implementation enables interoperable XML expression of ISO19115 compliant metadata.

5.4. PREMIS: Data Dictionary for Metadata Preservation

The Preservation Metadata: Implementation Strategies (PREMIS) international working group was set up by OCLC and RLG in 2003 to define a core set of preservation metadata elements, which could be applied broadly across the preservation community, and to examine a number of practical application issues. In 2005 the group published their final report which included version 1 of the PREMIS Data Dictionary. The accompanying XML schema allows PREMIS compliant metadata to be expressed consistently in XML. PREMIS is rapidly gaining community acceptance and is maintained by the Library of Congress. It won the Digital Preservation Coalition's 2005 Digital Preservation Award.

The PREMIS data model builds on the Open Archival Information System (OAIS) Reference Model (ISO 14721), and defines relationships between five digital preservation activities which it calls entities: Intellectual Entities, Objects (divided into three types: representation, file and bitstream), Events, Agents and Rights. 108 sub-entities and further qualifiers are defined for describing preservation activities of the latter four entities. Only 8 of these are mandatory. The PREMIS Data Dictionary's scope is restricted to the digital preservation activities of: maintaining viability, renderability, understandability, authenticity and identity. It assumes metadata will be auto-generated as much as possible. Implementers are expected to use other applicable metadata standards to describe Intellectual Entities, the characteristics of Agents, Rights relating to access and/or distribution, details of media and hardware, and the business rules of a repository.

6. Conclusion :

The foremost responsibility of digital libraries and archives is to ensure the future accessibility of information and preservation of valuable materials. Digital library main object organizing information, maintaining IPR and presenting, retrieving and visualizing digital material. Metadata shows the best information management. Library professional have used the concept behind metadata for generation. The information about document’s content brings power of a database to electronic documents, which help to users to search their concept like title, author everything very easily. Metadata development will progress through co-operation between communities of interest. For retrieval purpose Metadata is very much useful.

Metadata standards often start as schemas developed by a particular user community to enable the best possible description of a resource type for their needs. The development of such schemas tends to be controlled through community consensus combined with formal processes for submission, approval and publishing of new elements. The former ensure consistent structure to enable data sharing, searching, manage the creation process, record provenance and technical processes, and manage access permissions, while the latter ensure effective machine searches through consistent data entry and the inclusion of access points using controlled vocabularies such as authority files, thesauri or encoding.