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MirandaNet Fellowship Profiles (MirandaNet Archive - as of March 2015)
THE SEMANTIC WEB TECHNOLOGIES. How can we harness this technology for the delivery of metadata in education?
AIM: How to harness this wonderful technology and use it in the delivery of metadata in education.
A need exists to clearly identify the inter-relationship between barriers and drivers for technological change across the country. This can be achieved by looking at the Semantic Web Technologies, and how to identify resources using language vocabularies like the Dublin Core Metadata Initiative (DCMI), Really Simple Syndication (RSS), Friend of a Friend (FOAF) and many more alike. These vocabularies are already widely used in social networking sites and in business. We should be able to harness this technology for educational purposes as well.
Semantic Web technologies is a term often used to refer to technologies that aim to mechanise the notion of meaning which is then embedded into systems in order to automate interoperability and enable intelligent tasks.
This article will endeavour to give a broad and generic definition of the emerging Semantic Web. It will also look at technologies that power the Semantic Web, the Resource Description Frameworks (RDF) and the Web Ontology Languages (OWL).
The Semantic Web explosion is impending. By 2020, we should be connecting intelligences on the web where both people and things reason and communicate together. What is this Semantic explosion I am talking about? This is an evolution of the internet to 2020. The Semantic web is an extension of the current web, not its replacement. The Semantic Web is based on the idea that the data on the Web can be defined and linked in such a way that it can be used by machines for the automatic processing and integration of data across different applications.
The Semantic Web is a huge unbroken wave of innovation and investment that embraces four stages of internet growth. The first stage, Web 1.0, was about connecting information and getting on the net. The second stage is Web 2.0 and is about connecting people. There are a lot of Web 2.0 based applications aimed at supporting the management of various sources of knowledge such as text, photos, and videos. Some of these are web-logging applications i.e. Word-press, which is a personal publishing platform. The other one is Digg, a web content sharing solution where end users are looking at information from a collective community point of view. Flickr is another example of a Web 2.0 solution for sharing photos online.
The Web 3.0 is still in its infancy. It is about representing meanings, connecting knowledge, and putting them to work in ways that make our experience of internet more relevant, useful, and enjoyable. Some analysts are predicting that over the next decade, Web 3.0 will spawn multi-billion dollar technology markets that will drive trillion dollar global economic expansion to transform industries as well as our experience of the internet. Web 3.0 will enable people and machines to connect, share and use knowledge on an unprecedented scale and in new ways never seen before.
In order to develop semantic based technologies, meanings can be managed autonomously, separating them from data, content and application code, so that machines as well as people can understand, share and work with them. The semantic theory provides an account of meaning in which the logical connection of terms establishes interoperability between systems.
The Semantic Web is a web of meaning which is largely unrealised and maintains huge growth potential. Semantic Web would free us from the laborious task of trawling through information on the Web and negotiating with each other directly to carry out routine tasks such as scheduling appointments, finding documents and locating services. This can be achieved by providing sufficient context about resources on the Web and also providing the tools to use the context so that machines (or software agents) can find the right things and make decisions.
Consider a database with a schema that represents humans and canines as two separate tables. Applications that wish to extract the set of all mammals from the database must combine entries from both the human and canine tables. The semantics of the relationship of human and canines has been captured in the application, not the schema. A developer understood that humans and canines are each mammals. The Semantic Web should be able to capture this relationship.
The Semantic Web is a Web of data. The vision of the Semantic Web is to extend principles of the Web from documents to data. Data should be accessed using the general Web architecture. The Semantic Web will enable us to create a common framework that allows data to be shared and reused across application, enterprise, community boundaries, to be processed automatically by tools as well as manually, including revealing possible new relationships among pieces of data. In the Semantic Web world, data will not be encapsulated in code which cannot be accessed by other information and computer technology players, unless an agreement is reached between all involved players. Moreover, information would be updated on running time and will give more autonomous to both machine and human beings. The Semantic Web will move away from the idea of “my own code”; “This is my own black box”; “I am the only one who should be able to open it”. This means that a wide range of applications would be able to work collaboratively.
The wide range of applications would include data integration, knowledge representation and analysis, cataloguing services, improving search algorithms and methods, social networks, etc. Most interesting, the Semantic Web Technologies may act behind the scenes, resulting in a better user experience. They are not likely to directly influence the look on the browser.
Unlike the current Web of linked documents, the Web of linked data will allow publishers to describe data models, data concepts, and data records in such a way that they can be linked, described, and queried as if they were part of a single database.
Foundations of Semantic Web
Sceptics see Semantic Web as a futile exercise to resuscitate AI (Artificial Intelligence). It is true that the Semantic Web formats are grounded in these mathematical foundations; however, the Semantic Web fundamentally changes these AI concepts by making them dependent on URIs (Universal Resource Indicators) and compatible with XML. This combination of AI roots with Web foundations is what makes the Semantic Web unique from other modern software languages.
The Semantic Web helps to simplify a very complex world of data. The Semantic Web data formats are a way of levelling the field for data of any type and origin. In today’s digital world, data in all formats, structures, styles and languages is generated every second of the day. The Semantic Web should be able to capture the computational semantics of most other kinds of data formats and allows modellers to instantly connect all the data. The Semantic Web gives hope for more automated, routine, and predictable ways to bring data together, share it, and make it useful for newer software applications.
In June 2011, Apple announced that they were going to share a database “in the clouds”, and named it “i-cloud database”. Meaning its members would be able to share any data anywhere in the world. The restricting element is that this data can only be shared by users of Apple applications, including hardware, such as i-pad, i-phone and Macs. The Semantic Web should be able to break this data restriction. The Web itself should evolve into a global federated database.
Why Semantic Web?
This is the best way to link the entities and records among the enormous volumes of data governments collect every day. In this era of international terrorism, data can be shared amongst allied nations. Computer systems can be mashed up and remixed in times of emergency. This will enable police, rescuers, doctors and life saving personnel to quickly asses all the data they can, to best organize a response to the changing ground situation.
Business software will become more change resilient and less expensive and can find resources more quickly and easily. Remote technical problems can be easily diagnosed. The Semantic Web is fundamentally about using new technology that helps remix, reuse, and repurpose data on the Web in new ways. This technology, however, is not being researched fully to evaluate how it can be used in education, other than in business.
- Ubiquitous networking; data can be connected and intertwined without concern for its physical location.
- Open everything; the many parts of the network must remain open and not closed. Open data, open services and open identity.
- Adaptive information; this is an executable web and a data web. Web 1.0 (read only) is a single person editing a document. Web 2.0 (read-write) is a group of people editing a document, and Web 3.0 (read-write-execute) is a group of people creating bits of data outside of documents altogether, rendering the Web to be more connected, more fine-grained, and more dynamic.
- Adaptive service clouds; data is a service. Software services are not only about behaviour and programming interfaces, but are about enabling the publication and consumption of the data and data models as services inside cloud computing systems (software applications that are hosted entirely via Web protocols and services).
- Simulated intelligence; Web 3.0 will know what you want and understand what you mean. This can be achieved through a better use of algorithms for working with data.
The browser will start to understand more about the content of what you are browsing and begin to make recommendations or help organize the contents for you. Some browser tool bars will be able to tell you when you are looking at Web content that your friends have looked at and lets you know what they thought about it.
When it comes to search engines, the goal of a semantic search engine is to deliver exactly the information queried by a user rather than returning a list of loosely related keyword results that the user has to sift through.
According to Pollock (2009) there are a few search engines using Web 3.0 technology:
- Yahoo!: Using semantics for remixing content in search results (www.yahoo.com)
- Hakia: Using semantics for better search accuracy (www.hakia.com)
- Swoogle: Using semantics to search public ontologies (http://www.swoogle.umbc.edu)
- Zitgist: A Semantic Web browser for linked data (www.zitgist.com)
Semantic publication is intended for computers to understand the structure and meaning of the information, making information search and data integration more efficient.
Currently, social networking sites do not work with each other. Users are frequently frustrated when they are prohibited from transferring their own profiles from one social network to another. Instead, the social network users have to re-enter data from one web site to the other. The Semantic web site would enable the portability of such profiles with a format called FOAF (Friend of a Friend). Some social networks already allow import and export of FOAF data. You can control your own data on your own terms
The Semantic Web enables businesses to start creating their own webs of universal data connections throughout all their corporate data, content and documents. It provides a powerful global link from organization to organization and from anywhere in the world. Data is a valuable asset to any business. Data can help in evaluating past performance and in guiding future investments worth of trillions dollars.
Much of the data is logically connected, but only within an individual organization. It is physically disconnected in ways that prevent any search engine, database, or other content management system from linking up the data.
Databases all over the world contain billions of items of data. Some of the database is stored in proprietary database formats, and some is only in human readable form. This data must be made in a language understood by computers. A computer must be given a way to find and use the concepts, vocabulary and relationships that define the structure of that data.
Semantic Web databases – The heart of semantic applications is a semantic database. Unlike a relational database, whose main purpose in life is static data storage, the semantic database will contain highly adaptive, dynamic data records that respond to changing conditions.
Resource Description Framework (RDF).
Every source of data, every master of software system and application, and every platform integration and database provide an interface to its data and business rules in an RDF (Resource Description Framework). RDF is a compatible graph data language. The Semantic Web specifications, in particular RDF and OWL (Web Ontology Language), are the only technology specifications that were purpose built for use as a metadata language , entirely dedicated to describing and linking data of all sorts at Web scale. RDF is the basic language of the Semantic Web which uses a graph data format, in contrast to relational data formats and hierarchical formats (such as XML).
The RDF need to have the ability to describe:
- most kinds of data that will be available
- the structural design of data set
- the relationship between bits of data.
The RDF graph is based on the idea that every data item should have a unique Web identifier, called URI (Uniform Resource Identifier) references, and that every data item can be connected to every other item. A URI is a URI plus optional characters, such as the fragment identifier (the part that follows a # sign after a URI). A URI may refer to either a Web name or a location; a URL (Uniform Resource Locator) may refer only to actual web locations. A URI can be used to identify a concept, a tangible thing that cannot be downloaded, or a chunk of data that can be retrieved over a network. To identify a resource, a URI is paired or associated with the resource, not with any other resource. A resource can also be identified by its properties and relationships with other resources.
Resources: All things described by RDF expressions are called resources. A resource can be an entire web or part of the web, a whole collection of pages, an entire Web site. We also should take note that a resource can be also be an object that is not directly accessible via the Web; e.g. a printed magazine.
Properties: A property is a specific aspect, characteristic, attribute or relation used to describe a resource.
However, we have to take note that there are thousands of people called Tendai in my native Zimbabwe and diasporas. Names are not unique, but do not represent the same person. To identify a resource, a URI is paired or associated with the resource, not with any other resource. This can be become clearer when we look at OWL.
Statement: RDF uses a simple data model. In the Semantic Web, our main aim is seeking for resources, and there are statements that can be made about those resources. A single statement links two resources. These statements are like simple sentences that have subject-verb-object structure. For example; Tendai lives in Hampshire. Tendai=subject (Resource); lives in=verb (Predicate); Hampshire= object (literal). In RDF a statement is sometimes called a triple (because it has three parts) and the equivalent of a verb is called a predicate or property. Object can also be termed as a value.
Dublin Core Metadata Initiative.
This URI http://purl.org/dc/elements/1.1 is directed to the Dublin Core Metadata Initiative (DCMI). This is a project whose goal is to develop metadata standards for a wide range of applications, including document and multimedia descriptions. The project maintains a registry of metadata terms that can be browsed or searched. It provides a set of words and terms that enables any software that shares its “dialect to automatically interoperate” Pollock (2009). Having looked at the Dublin Core Metadata Initiative, it would be appropriate that we also look briefly at other few RDF applications.
Really Simple Syndication (RSS)
The RSS technology is making blogging more interesting and popular by letting people distribute summaries of new blog stories efficiently and cheaply. An RSS file describes a site with mete data, including its name, its URL, date and its channels. It allows web users to view another site’s content without actually visiting it. There are several versions of the RSS format, all of which are small, XML based languages. This is a simple, but powerful way of syndicating just about any metadata you need to publish to anyone.
Friend of a Friend (FOAF)
The Friend of a Friend project was one of the first to recognize the simple power of social networks. It offers tools to relate people through a model that contains typical social attributes such as a name, email address, interests, gender and the like.
(This is an ongoing study and still in its infancy. The next section will attempt to discuss Web Ontology Languages (OWL) before we endeavour to apply Semantic Web Technologies to the delivery of metadata in education). The full version of this document, showing all the graphs and examples of RDF, RSS and FOAF Syntax is available.
Jeffrey T. Pollock. Semantic Web for Dummies. 20 March 2009. John Wiley and Sons.
Thomas B. Passin. The Semantic Web. 2010. Manning.
W3C. http://www.w3.org/. Accessed on 30/06/2011.
Semantic Web Technologies.
ICT, Teacher Education and Pedagogy.
Currently working on Semantic Web Technologies, focusing on evaluating the Resource Description Frameworks and how they work together with the available vocabularies, such as the Dublin Core Metadat Initiative (DCMI), Friend of a Friend (FOAF) and Really Simple Syndication (RSS).
My objective is to find ways we can use the Semantic Web Technologies in the delivery of education. How to apply this fantastic technology in education? The success of this technology in the business world is evident, but not so clear in education. For example, what are the implications of data sharing in education? How best can we achieve this using the Semantic Web Technology? With so many applications being created each day, how best can we interoperate seamlessly in the delivery of content in education, regardless of the various applications available. These are some of the questions i do hope to get answers by researching the Semantic Web Technology.
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