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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>World Wide Web in the service of schooling: Semantic Web as a solution for language teaching in Cypriot secondary education*</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Neofytou Chrystalla</string-name>
          <email>chrystalla.neofytou@st.ouc.ac.cy</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Open University of Cyprus</institution>
          ,
          <country country="CY">Cyprus</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>This is joint work with my PhD advisor, Dr Thanasis Hadzilacos, written and presented as a single author work for the purposes of the Doctoral Consortium of the Eighth European Conference on Technology Enhanced Learning</institution>
          ,
          <addr-line>Paphos, 17</addr-line>
        </aff>
      </contrib-group>
      <fpage>71</fpage>
      <lpage>78</lpage>
      <abstract>
        <p>This paper examines some suitability aspects of existing web search engines in relation to the content and the stated learning objectives of language teaching in Cypriot secondary education, focusing on the language course of the third high school grade (G9). The end goal is to put the internet in the service of schooling; specifically to categorize the results returned by the search engine into genres in order to facilitate user (teacher or student) in choosing the most appropriate texts for their learning purposes. The tools for categorizing texts are being sought in the field of Semantic Web technology, such as metadata, ontologies, software agents, and, the techniques in the fields of Natural Language Processing (NLP), Information Retrieval (IR), Information Extraction (IE) and Text Mining. The paper proposes the categorization of texts into six major genre categories according to their external (structural) and internal (linguistic, stylistic) characteristics. For the purpose of this research, the MeDa13 metadata model was designed on the basis of the standard metadata model Dublin Core, and the Textual Genres Ontology (TeGO) was developed for describing the concepts mentioned in genres. In this work, we present the theoretical background for the development of the proposed models (MeDa13 and TeGO), and also the methodological plan to achieve the research objective, which is the categorization of texts into genres considering the content and learning objectives for language teaching.</p>
      </abstract>
      <kwd-group>
        <kwd>Semantic Web (SW)</kwd>
        <kwd>Metadata</kwd>
        <kwd>Ontologies</kwd>
        <kwd>Natural Language Processing (NLP)</kwd>
        <kwd>Information Retrieval (IR)</kwd>
        <kwd>Information Extraction (IE)</kwd>
        <kwd>Text Mining</kwd>
        <kwd>Greek Language Teaching</kwd>
        <kwd>Cyprus Educational System</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        The internet as a source of information and a means of communication, either
synchronous (chat) or asynchronous (email, blogs), has a dominant place in all fields of
human everyday life, including education. The fact that searching and information
gathering is the most common activity on the internet, brings up several questions
regarding the real usefulness of the internet in school education and the suitability of
the results returned by the existing classic web search engines in relation to the
context and the learning objectives as set out in the curriculum of Cyprus Ministry of
Education and Culture. Assuming that the internet is useful for the results returned to
the user, this study seeks answers regarding the suitability of the results returned
focusing on the learning purposes of language course of the third high school grade
(G9). The frequent return of unsuitable results, as noted in the international literature,
is related to the operation of existing web search engines, which are based on using
keywords and conducting searches that are related more to the word spelling than
with semantics [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. The difficulty of automatic recognition of semantic content of the
information stored in the Web, known as lack of semantics, orients the research
interest of this study in the field of Semantic Web (SW).
      </p>
      <p>The end goal is to design and develop a system that will distinguish textual genres,
for example, a history text from a literary text, a text of the daily press from a sketch
etc, and will organize internet data according to the textual characteristics of each
genre. The first step is the definition of each (textual) genre and the clear wording of
assessment criteria for categorizing texts. The long term vision is to build a search
engine that returns the search results categorized into genres. This search engine will
operate on the basis of specific assessment criteria for the texts, search the internet,
filter all the data and sort them in the categories of genres. Therefore, the research
looks for a tool that will 'help' the computer to process data, to understand the
meaning e.g. of a historical text and the definition given for this genre, in order to filter the
texts and subsequently to classify them into the genre categories that have been
created. This means that the information stored in the computer should be
semantically enriched. The research is oriented in the field of SW and seeks the tools with which
the semantic enrichment of the information will be achieved, and, subsequently, the
classification of internet data in the categories of genre created for the needs of this
research. Additionally, the study looks for a tool that will select texts from all the
available texts on the web and correctly register them in the appropriate categories.</p>
      <p>This work proposes the automatic categorization of Greek texts that are available
on the internet into genres, as presented and used in the school textbook for teaching
Modern Greek language in the third high school grade (G9). To achieve this goal, an
algorithm is developed and the relative techniques for categorizing texts are inquired
in the fields of Natural Language Processing (NLP), Information Retrieval (IR),
Information Extraction (IE) and Text Mining. The tools of SW technology, such as
metadata and ontologies, are used to define the concepts or terms and the
relationships between them, and to describe the related knowledge of a specific thematic
domain, e.g. Medicine, Education etc., respectively. For the purposes of this study, a
metadata model called MeDa13 is developed on the basis of the standard metadata
model Dublin Core, and the Textual Genre Ontology (TeGO) is formed in order to
represent the knowledge which is relevant to genres.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Research Questions</title>
      <p>The main research questions of this study are summarized as follows:
1. Does the operation mode of the internet and existing search engines meet the
learning objectives of schooling, particularly for language teaching? Are the results
returned from the existing search engines suitable for the content and the learning
objectives of language teaching?
2. What would be the ideal scenario for the operation of the internet in relation to the
educational needs? What would make an 'ideal' search engine? (ideal = it would
serve the learning objectives, return the most appropriate results in relation the
query set by the user).
3. Is the appropriate technology to 'place' the internet in the service of schooling
available? Is SW the solution for ensuring the suitability of the results returned,
always in connection with the content and the intended learning purposes? Which
tools are available (metadata, ontologies, software agents etc.) and, which of them
can be used to better organize the material on the internet in order to make it
suitable for use in language teaching? Are the existing models suitable for the purposes
of this work?
4. How should the material on the internet be organized? Which techniques for
categorizing texts are available and which of them serve the objectives of this work?
3</p>
    </sec>
    <sec id="sec-3">
      <title>Current knowledge of the problem domain</title>
      <p>Search engines usually operate on the basis of keywords depending on the query
entered by the user. The fact that these searches relate more to the spelling of the
keyword than to semantics often results in unsuitable results. This is due to the
construction and operation mode of the existing web search engines and their weakness to
carry out the necessary semantic correlations between the query and the real objective
of the user's search. Therefore, while the whole process of web search fascinates its
users, at the same time, it is indifferent to computers while as machines fail to
understand and interpret the information stored in them. The result is the creation of a
communication gap between humans and machines related to human’s ability to read
and interpret a word, phrase or sentence by associating it with the appropriate
conceptual content resulting either in general or specific findings or reaching on reasonable
inferences after the juxtaposition of two or more truthful sentences. Computers are
unable to proceed to such automated correlations and (reasonable) inferences. For
example, when humans read the sentence "O Μιχάλης είναι μεγαλύτερος από τον
Αντρέα" (Michael is older than Andreas) easily conclude that "Ο Αντρέας είναι
μικρότερος από τον Μιχάλη" (Andreas is younger than Michael). The machine cannot
understand the relative age of the two subjects, which is expressed using the
comparative degree of the adjective "μεγάλος" (old) and, also to comprehend the syntax used
to compare two objects or subjects in Greek language. Furthermore, the phenomenon
of multiplicity, i.e. the use of one word to describe different objects, for example, the
word "language" that can be interpreted as "anatomical organ", "communication tool",
"fish species" etc, and the phenomenon of synonym, i.e. the existence of two or more
words that describe the same object or situation but differ in style, performance or
expressive significance, for example, the word "clever" and its synonyms "smart", "
intelligent", "very clever" etc, make it even more difficult for the search engine to
understand the question (query) set by the user. SW based on the creation of a
common semantic basis (framework) allows the automation of these functions with
minimum human intervention aiming to produce meaning and retrieve the most suitable
information.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Existing solutions</title>
      <p>The solution to overcome the structural and functional disadvantages of World
Wide Web (WWW) seems to be SW, which is built upon the foundations of the
existing web. SW, as the next step, structures (organizes) data correlating them with
objects and entities of the real world, and, provides the necessary knowledge for any
field of interest (e.g. Medicine, Education etc.). Using SW tools such as metadata and
ontologies, computers are equipped with the knowledge of a specific subject area and
the appropriate tools (data information, vocabularies, etc.) that enable them to 'read',
process, interpret and understand the content of the information stored in them. SW
bridges the communication gap between machines and humans based on the idea of
having a commonly perceived, between computers and human beings, semantic
framework of concepts and terms that refer to real objects and entities in the real
world, expressing their mutual conceptual and semantic relations and representing the
relevant knowledge. A semantic search engine returns the related to the search
objective results after carrying out the essential conceptual correlations, linking concepts
and objects with the most suitable semantic content.</p>
      <p>
        Semantic Web is an initiative of the WWW Consortium (W3C) that was inspired
by the creator of WWW, Tim Berners-Lee. Its goal is to structure information and to
improve the current web, placing a semantic layer that allows machines to understand
and process the (human) information effectively [
        <xref ref-type="bibr" rid="ref2 ref3">2-3</xref>
        ]. This web semantic enrichment
is based on the vision of making the available information machine readable and
understandable by equipping computers with the knowledge -in the form of
dictionariesso that they can understand the semantic content that concepts and terms carry. The
basic principles of SW are to maintain the distributed web content, the representation
and retrieval of information, the representation of concepts of various subject areas
(e.g. Education), which is achieved by using ontologies and the existence of software
agents [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The term 'ontology' is taken from philosophy and is used, according to
Aristotle, to describe the science of speech of being. In the field of computer science
'ontology' is understood as a divided and shared understanding of some domain that
can be exchanged between people and systems applications. It is a standard (formal),
categorical (explicit) specification of the distributed (shared) conceptual
representation (conceptualization) [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. It provides the required knowledge and vocabulary for
the description (representation) of a specific field of interest (W3W). Software agents
are special programs undertaken to 'look' on the internet and gather information, on
behalf of the user, from various sources that have semantic content [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The
description of the relationships between concepts (or terms) and objects (or entities) is
achieved by using metadata that is information about online resources or other objects
that are machine understandable [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. It is structured information that describes,
explains, locates or facilitates recovery, uses or manages an information resource.
      </p>
      <p>
        Concerning the existing text categorization techniques, NLP moves in the field of
linguistic analysis of texts at different levels. These are the morphological, lexical,
syntactic, semantic, discourse and pragmatic level [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. NLP adopts linguistic theories
and examines their computational effectiveness based on linguistic data in order to
understand natural language and resolve any ambiguities [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. IR refers to the
automatic retrieval of documents that are related to the query inserted by the user. It checks
the representation and the relevance of a document and a query. IE is closely
connected to the field of NLP, as it automatically extracts structured information from
unstructured and/or semi-structured machine-readable documents, a process that
concerns mostly human language texts by means of NLP [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Text Mining refers to the
process of deriving information from text involving the process of structuring the
input text [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Some of its tasks are text categorization, text clustering and concept/
entity extraction.
5
      </p>
      <p>Preliminary ideas
1. Concentration of text genres to be included in the list of categories and formulation
of general definitions for each genre. Recording the characteristics for each genre
that will be used as assessment criteria, and grouping the texts in the following six
major categories: Informative, Scientific, Literary, Artistic, Multimodal and
Foreign_ Language.
2. Development of the algorithm for categorizing texts into genres and formulation of
rules and axioms (assumptions) that lead to reasonable conclusions regarding the
distinction of one genre from another (classification criteria).
3. Design and development of the metadata model MeDa13 based on the Dublin
Core, for the enrichment of digital recordings (text) information on the (text) genre.
MetaDa13 includes the following elements (13): Title, Creator, Subject, Publisher,
Rights, Date, Date Modified, Source, Type, Description, Language, Data Writing,
Authorial Intention, and, has two applications. The simple application is used to
categorize texts into the six major categories of genre (e.g. Informative) and
includes only five elements: type, description, language, data writing and authorial
intention. The composite application is used for more specified categorizing
specific (sub-categorization, e.g. Journalistic) and includes all thirteen elements.
4. Design and development of Textual Genre Ontology (TeGO) for the description of
concepts (terms) relating to genres (definitions and attributes) and their relations.
6</p>
    </sec>
    <sec id="sec-5">
      <title>Proposed Approach and Research Methodology</title>
      <p>The course of the research process in this paper is as follows:
1. Literature review to gather information on how World Wide Web and Semantic</p>
      <p>Web, and the web search engines operate (descriptive approach).
2. Conducting an experiment to search and gather information from the internet, for
the purposes of an educational activity designed according to the content and
learning objectives of a randomly selected topic from the school textbook for teaching
Modern Greek language in the third high school grade (G9). The aim is to
investigate the suitability of the results returned from the existing web search engines in
relation to the content and the learning objectives of the language course
(experimental approach).
3. Study of the curriculum of Cyprus Ministry of Education and Culture and the
school textbook for teaching Modern Greek language in the third high school grade
(G9). Wording of general conclusions concerning the suitability or unsuitability of
the results returned from the experiment.
4. Study of the available Semantic Web tools (metadata, ontologies, software agents)
and examination of their suitability for the purpose of this work.
5. Study of the existing techniques for categorizing texts in the fields of NLP, IR, IE
and Text Mining, and search for the most appropriate for the needs of this study.
6. List all textual genres included in the school textbook and categorization into six
categories created for the purposes of this study: Informative, Scientific, Literary,
Artistic, Multimodal (texts using many modes i.e. language, sound, picture) and
Foreign_ Language. Wording of general definitions and recording of the
characteristics for each category and subcategory of genre. Categories and subcategories
are defined according to the external and internal characteristics of each genre.
7. Gathering sampling (text) material from the internet in two phases: random and
semi-directed selection of texts, using Google search engine and the keyword
'language'. Registration of the results (sample texts).
8. Categorizing a hundred selected results (texts) according to the general definitions
and characteristics of genres (step 5).
9. Set two control groups consisted of ten primary school teachers and ten secondary
school teachers respectively, to test the validity of definitions and assessment
criteria by distributing questionnaires.
10. Gathering the results from the questionnaires and comparison of teachers’ answers
between them and with the results of the initial categorization (step 7). Wording of
conclusions of the process.
11. Development of an algorithm on the basis of the assessment criteria for automated
text categorization in the proposed categories of genres.
12. Design and development of the metadata model MeDa13, consisting of thirteen
elements, on the basis of the standard metadata model Dublin Core, in order to
describe the relationships between concepts (or terms) and objects (or entities).
13. Design and development of the Textual Genre Ontology (TeGO) to represent the
knowledge related to the field "language teaching" and to describe the concepts
relating to genres and their relationships.
7</p>
    </sec>
    <sec id="sec-6">
      <title>Discussion of how the suggested solution is different, new, or better as compared to existing approaches to the problem</title>
      <p>The originality of this work lies in the fact that it is carried around the axis of the
content and the stated learning objectives for the language course for the third high
school grade (G9), focusing on the textual material used in accordance to the lines of
the curriculum of Cyprus Ministry of Education and Culture. The target group is
teachers and students that use the internet for gathering information in the context of
an educational activity and, the body of texts examined and categorized into genres is
mainly written in the Greek language. Regarding the examination of the unsuitability
of the results returned from the existing web search engines this study suggests the
categorization of internet data into genres using Semantic Web tools, i.e. metadata
and ontologies, in order to achieve the learning objectives of language teaching. The
importance of this work lies in the proposal for the construction of a semantic search
engine that will serve the purposes of language teaching and schooling, in general, as
it will return search results after carrying out the necessary semantic associations and,
finally, categorizing them into genres, underlining at the same time the need of
multiclassification according to the external and internal characteristics of each text.</p>
    </sec>
  </body>
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