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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>October</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Ontology-based learning environment model of scientific studies</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Roman A. Tarasenko</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stanislav A. Usenko</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yevhenii B. Shapovalov</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Viktor B. Shapovalov</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Adrian Paschke</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Iryna M. Savchenko</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>The National Center “Junior Academy of Sciences of Ukraine”</institution>
          ,
          <addr-line>38-44 Degtyarivska Str., Kyiv, 04119</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2022</year>
      </pub-date>
      <volume>1</volume>
      <issue>2021</issue>
      <fpage>0000</fpage>
      <lpage>0001</lpage>
      <abstract>
        <p>Nowadays, there is a wide variety of scientific articles. Due to this fact, it is hard to read and be familiar with all of them. Also, it is hard for a young scientist to understand the complicated terms and methods that are used in a specific research domain. This problem was partially solved by bibliographic management software and other specific software. This article is devoted to the development of an approach for structuration and processing sets of studies using the IT Platform Polyhedron using an ontology-based hierarchical model. In its structure, the ontological graph is complex because it has additional branches from child nodes. The basis of our solution was IMRAD which has been represented in the view of nodes. Those nodes have been connected with specific representations of IMRAD elements. Specific articles have been represented in the view of leaf nodes. That could help to use the taxonomies for the structuration of the articles. Each data block is in the form of separate attributes of the ontological node. The proposed solution allows to obtain structured sets of studies and to separate their characteristics. Thus, the proposed ontology provides the possibility to view all methods, measured parameters, etc. of the studies in a graph node structure and use them to find the studies where they were used.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;cognitive IT-platform Polyhedron</kwd>
        <kwd>ontology</kwd>
        <kwd>ontological tool</kwd>
        <kwd>scientific studies</kwd>
        <kwd>scientific reports</kwd>
        <kwd>learning environments</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Usage of information technologies (IT) in various fields of research activities and the
capability of software support in science to automatically classify and structure information, e.g.,
in publication data, becomes increasingly important. Nowadays, there are huge amounts of
research data available that isn’t structured, e.g., publications, presentations, etc. It is
complicated for young researchers and scientists to use such large amounts of publication data.
During the research process, young scientists are looking for, e.g., examples of research methods
and parameters. However, this task is challenging at their early stage of the scientific career.
Such literature search and analysis problems (e.g. state of art analysis) are challenging for
every scientist (including youth, school researchers) during the process of preparing papers
and reports. For instance, according to Lens.org, the number of articles on biogas in 2002 was
approximately 134, then in 2014, the number grew up to almost 1164, as shown in figure 1.</p>
      <p>So, it seems relevant to provide a solution that can simplify processing and
information/knowledge extraction in scientific publications. There are two hypotheses in our study.
The first one is about structuring and digitalization of the data, which can simplify finding the
details about the research method. The second one is about structuring the results of previous
studies, which can be represented as data of the informational system. Previously, this goal was
partially achieved using metadata for data processing. In this paper we further contribute with
a semantic ontology and more expressive semantic metadata approach.</p>
      <sec id="sec-1-1">
        <title>1.1. Using metadata to provide data management in science publications</title>
        <p>
          To support publication data management, it is relevant to use metadata about each paper. This
metadata represents the data about the publication. In this case, relevant information about
each specific publication can be represented by the metadata. Metadata can include, e.g., contact
information, year of publication, author details, instrument and protocol information, survey
tool details and much more [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ].
        </p>
        <p>
          For instance, reference management software maintains a database of articles and creates
bibliographies and reference lists for the written works. This software simplifies the record of
metadata. There are several popular reference management software, for example, Refworks,
Mendeley, EndNote and Zotero [
          <xref ref-type="bibr" rid="ref2 ref3 ref4 ref5">2, 3, 4, 5</xref>
          ]. All of these managers can save profiles, build a
database of citations, save PDF files and extract metadata from them, import references from
library catalogues, websites, and other citation managers [
          <xref ref-type="bibr" rid="ref6 ref7 ref8">6, 7, 8</xref>
          ].
        </p>
        <p>However, these systems only use limited metadata vocabularies without expressive semantic
models. For instance, such systems do not support metadata concepts such as “Results”,
“Materials and methods”, “References” etc. All these systems do not provide a systematic approach,
they are not completely semantically structured and not hierarchical.</p>
      </sec>
      <sec id="sec-1-2">
        <title>1.2. Methods for automatic literature review processing</title>
        <p>There are existing diferent types of metadata information that we can use to structure the
articles, for example, by the relation to source, by the function, by the purpose, by the language,
by the time:
• By the “Relation to Source”: During this method, the user defines the type of text that
can be included in a classification program. A classification that is composed of extracts
having exact sentences of a source document is known as an extractive summary. That is
the simplest type of classifier.
• By the “Function”: with this method, user can use any helpful and relevant information
from source documents, for example, an abstract of a scientific article or the reviewers’
opinion on the quality of work.
• By the “Purpose”: This method structures the article by its purpose or main idea. The user
needs to write down the general-purpose or sense of the text in the program by himself.
• By the “Language”: A classifier can be monolingual or multilingual. The monolingual
classifier uses only one language and produces an output classification in the same
language as the input document whereas, the multilingual classifier uses multiple languages
and gives an output classification in one of the languages from the input document.
• By the “Time”: It is possible to arrange the articles by the time of their publication. To do
so, the user must enter the publication date of the article in the system, then the system
will arrange the article in an appropriate section.</p>
        <p>In our opinion, there is a lack of methods that we can use for the structurization of scientific
articles. Also, it is necessary to add “By the Results” and “By the methods” methods.
• “By the Results” this method structures the article by its results or conclusions. The user
needs to write down the outcomes or verdicts of the text in the program by himself.
• “By the Methods” this method structures the article by the scientific methods or
experiments that are used in the essay.</p>
        <p>Considering that most of the articles have a typical IMRAD (Introductions, Methods, Results,
Abstract, Discussion) structure, it seems advisable to build an algorithm that uses data of many
specific articles to create ontological graphs, that can be integrated in specialized educational
environments for young scientists.</p>
      </sec>
      <sec id="sec-1-3">
        <title>1.3. Instruments for creation of ontology-based learning environments</title>
        <p>A learning environment is a diverse platform where users engage and interact to learn new
skills. While learners can learn in various settings, the term typically refers to a digital
alternative for the traditional classroom. To improve learning eficiency and adaptability, formalized
information resources that provide a high degree of structuring should be used in learning.
An ontological approach could support this. The ontological approach provides a holistic and
systematic approach to the study of various information sources and a specific subject domain,
ensures the conceptualization and taxonomization of terms within the subject area and the
existence of relationships between the terms of diferent subject areas to ensure multidisciplinarity.
Computer ontologies are one of the efective mechanisms for ensuring a stable digital learning
environment.</p>
        <p>In recent years significant progress was made in developing ontologies. In this article, an
“ontology” is a term that means a software or web system that consists of nodes with data. All
ontology nodes are arranged in a specific hierarchical order, often referred to as an ontological
tree or ontological graph. The node from which all branches start is called the root node. The
other nodes are called subsidiaries.</p>
        <p>
          One of the most perspective solution, in our opinion, is ontologies [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. For example, we can
use hierarchies with multicriteria techniques during the classification of metadata of various
articles. Ontologies aim to capture the domain knowledge in a general way and ensure a
common understanding of the domain.
        </p>
        <p>IsaViz is a virtual environment for viewing and creating RDF models in the view graphs.
IsaViz imports RDF/XML and N-Triples, and exports RDF/XML. Apollo is the program for
modelling knowledge systems. Apollo knowledge system base consists of hierarchically
organized ontologies that can be inherited from other ontologies. SWOOP contains OWL (Web
Ontology Language) validation and ofers various. OWL presentation syntax views. At SWOOP,
Ontologies can be compared, edited, and combined. Protégé 3.5 is a knowledge-based ontology
editor that provides a graphical user interface. It ensures better flexibility for metamodelling,
enables the construction of domain ontologies.</p>
      </sec>
      <sec id="sec-1-4">
        <title>1.4. Ontological problems</title>
        <p>Nowadays most of the common systems (such as Mendeley, Scopus etc.) provide support
for displaying of data but not for comparison and providing search functions. Also, given
that articles in the same domain have the same indicators, the metadata of the results can be
represented as ontology node attributes and then processed.</p>
        <p>
          Previously, ontological graphs were used to systematize scientific articles [
          <xref ref-type="bibr" rid="ref10 ref11 ref12 ref13 ref9">9, 10, 11, 12, 13</xref>
          ].
Systematization and structuring in such ontological systems were based on diferent approaches
such as using of scientific article recommendation system [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], a scientific articles tagging system
[
          <xref ref-type="bibr" rid="ref11">11</xref>
          ], machine learning and automatic summarization [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. None of the proposed ontological
approaches [
          <xref ref-type="bibr" rid="ref10 ref11 ref12 ref9">9, 10, 11, 12</xref>
          ] can’t provide a decent level of structurization and systematisation.
        </p>
        <p>
          We have proposed to use the cognitive IT platform Polyhedron [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] for this aim. The
core of the Polyhedron system consists of advanced and improved functions of the TODOS
IT platform [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] described in previous works. The Polyhedron is a multiagent system that
provides transdisciplinary and interactivity in any study [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ]. Besides, cognitive IT-platform
Polyhedron contains a diferent variety of special functions like auditing [
          <xref ref-type="bibr" rid="ref15 ref16 ref17">15, 16, 17</xref>
          ], semantic
web, information systematization and ranking [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ] transdisciplinary support [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ], internal
search [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ], and have all advantages of ontological interface tools [
          <xref ref-type="bibr" rid="ref16 ref21">16, 21</xref>
          ]. Due to active states
are hyperratio plural partial ordering [
          <xref ref-type="bibr" rid="ref19 ref22">19, 22</xref>
          ], cognitive IT-platform Polyhedron is an innovative
IT technology of ontological management of knowledge and information resources, regardless
of the standards of their creation.
        </p>
        <p>
          The proposed solution can be used with other applications in the field of structuration studies
like a virtual educational experiment, provide STEM approach in education [
          <xref ref-type="bibr" rid="ref14 ref23">14, 23</xref>
          ], using the
technology of augmented reality education [
          <xref ref-type="bibr" rid="ref24 ref25">24, 25</xref>
          ], educational and scientific environments
[
          <xref ref-type="bibr" rid="ref14 ref20">14, 20</xref>
          ].
        </p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>2. Materials and methods</title>
      <sec id="sec-2-1">
        <title>2.1. Ontology creation mechanism</title>
        <p>
          The proposed research is based on approach that was proposed before [
          <xref ref-type="bibr" rid="ref26">26</xref>
          ], but it provides
management and structuring of set of the studies, not single. To create ontologies in cognitive
IT-platform Polyhedron, Google Sheets are used to collect and structure the information (see
example in figure 2). The sheets with study report data (structure file and numeric/semantic data
ifle) are downloaded and saved in .xls format. The data was separated with expert involving and
based on principle that researches of same field have similar input and resulting characteristics.
Same is relevant to field of anaerobic digestion [
          <xref ref-type="bibr" rid="ref27 ref28">27, 28</xref>
          ] that was taken as example to provide
structuring and processing using proposed method. The files are loaded to editor.stemua.science
to provide graph generation (a part of the cognitive IT platform Polyhedron). After that, the
generation of the graph nodes (in .xls) with its characteristics using structure file is carried out.
The obtained graphs are saved in .xml format and located in the database. The graphs are filled
by semantic and numeric information for ranking or filtering. Ontological nodes are formed
using predicate equations.
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. Description of the works were used to demonstrate the structuration mechanism</title>
        <p>To demonstrate the structuring of the educational study reports, a master thesis of the National
University of Food technologies “Development a method for utilization of anaerobic digestion
efluent at LLC Vasylkivska Poultry Farm” (in further – report “A”) and a study report prepared
for the defence of an educational study in the Junior academy of sciences of Ukraine scientific
competition “Development a method for utilization of anaerobic digestion efluent” (in further –
report “B”) are used as input data. Two ontologies have been built, the structure of which
duplicates the content of the study reports. All numeric data was separated to provide information
processing and to provide integration between those works. Their titles have used as the parent
node for the ontological graphs. All ontological graphs in the cognitive IT platform Polyhedron
have been linked to each other by the mechanism of internal search. Further scientific studies
will be linked in the graphs by edges (links) to provide better connection.</p>
      </sec>
      <sec id="sec-2-3">
        <title>2.3. Ranking tools</title>
        <p>
          Study reports “A” and “B” were also compared with each other by the following criteria:
“Shortterm economic perspective”, “Long-term economic prospects” using the ranking tool. For
creation of the ranking ontologies have been used by the module “Alternative” which is described
in previous works [
          <xref ref-type="bibr" rid="ref18 ref29">18, 29</xref>
          ]. The nodes of the graph have been filled with semantic data grouped
in semantic classes. The ranking uses grade scale from one to ten point to underline the
importance coeficient.
        </p>
      </sec>
      <sec id="sec-2-4">
        <title>2.4. Auditing tools</title>
        <p>To provide an audit, the “standard” graph (with which the comparison is done) and the
“comparison” graph (which is compared with the “standard”) have been created. The “standard”
ontology graph contains the data on hypotheses, subjects, objects of study, keywords, and other
parameters, of the studies reports done before. For the “standard” graph, each parameter was
presented in a separate node. The content of this ontological graph “standard” is updated and
supplemented constantly.</p>
        <p>The nodes of the “comparison” graph have been presented with the names of the works which
need to be audited with the “standard” graph. The parameters of the work used to audit with
the “standard” graph have been located in the metadata of each separate node. The metadata
type names were identical to the names of the nodes of “standard” graph to provide interaction
between graphs.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Results</title>
      <sec id="sec-3-1">
        <title>3.1. Model of creation ontology to systemizing</title>
        <p>As was noted before, IMRAD is widely used to prepare research and science papers. It is possible
to provide structuration by the usage of IMRAD components as parent nodes. So, the parent
nodes can be represented by Introduction, Methods, Results and Discussion. The discussion
part can’t be easily structured by an ontology. The most contractionary part that it contains
are the analysis and the comparison of the obtained data by the researcher. Specific parts of
IMRAD will be used as branch nodes, and the study will be used as a leaf node. So, the general
structure of the ontology that structures the research data is represented as:
 ∈ {, , ,  }
where  – set of reports,  – sets of Introduction of all study,  – set of Methods of all
study,  – set of Results of All study,  – instruments of processing of the results of set of
studies discussions.</p>
        <p>To provide better systematization we have split the introduction into two diferent parts –
basic metadata and literature review:</p>
        <p>= ⟨ , ⟩
where   – is a set of basic metadata of study,  – a set of Sourses used for Literature
Review.</p>
        <p>The basic metadata node of the study is linked with the graph’s leaf nodes that characterized
basic data on the study such as hypothesis, object, subject, practical value, and scientific novelty,
etc. So, the nodes of the report’s basic metadata of the study can be presented as a further
equation:</p>
        <p>= ⟨, , ,  ,  ⟩
where  – hypothesis or hypotheses of each specific study;  – object of the study of each
specific study;  – subject of the of each specific study;   – practical value of each specific
study;  – scientific novelty of each specific study.</p>
        <p>The main advantages of using such a structure are that some parts of the introduction
materials and methods and results (measured parameters) of study (reports) can coincide. A
few specific studies that coincide will be linked by nodes (in case of methods and results) or
by classes of data (in case of keywords or scientific novelty) due to using the same subnodes
of the ontology. Let’s represent each work as a set of the Introduction, Methods, Results, and
Processing of the data (Discussion):</p>
        <p>So, these studies can be integrated in a single ontology using IMRAD:</p>
        <p>= ⟨ ,  ,  ,  ⟩
 = ⟨ ,  ,  ,  ⟩
 = ⟨ ,  ⟩ = ⟨ ,  ,  ,  ,  ,  ,  ,  ⟩
(1)
(2)
(3)
(4)
(5)
(6)</p>
        <p>The same approach will be applied to each element of the IMRAD structure study. Generally,
it can be represented as:

 = () = ∑︁ 

where  – every separated scientific method.</p>
        <p>In a diferent study, a diferent set of methods can be used. However, some of them can
coincide. Thus, set of methods used in two diferent study may be represented as:
(7)
(8)
(9)
(10)
 = ( ) = {, , , }</p>
        <p>= ( ) = {, ,  }
And, so,  coinciding to both  and  :</p>
        <p>∈ { ,  }</p>
        <p>Therefore, in this case, and  can be used as a parent node that connects two diferent
studies. The node  itself will contain general theoretic information on it, and node 
and  will contain information on the specific case of its usage and measured parameters
using it.</p>
        <p>Similar mechanism can be provided by using specific ontology tools using metadata. For
example, there will be a hierarchical approach for representing and usage of keywords:
( ) =  “”   “  ” {, , , }, (11)
where ( ) – node of the basic metadata that integrates all keywords;  – specific
keyword.</p>
        <p>Also, as was noted in the introduction, the metadata of each work will be used for filtering
the information, and for supporting specific processing functions of the IT solution Polyhedron.
Such specifics mechanisms are AUDIT and RANKING. Metadata can be included in each node.
For the parent node metadata will be used to represent the general information (for example,
essence of the method itself), and the resulting leaf node will contain the specific metadata
related to specific study (such as specific results of the study obtained using set methods M; for
example, metadata: 5.35, and its class: “Ammonium nitrogen content, g/L”). So, metadata, with
the same class, will be processed by using filtering by users request or by ranking using the
ranks of the nodes for specific classes (or their set) based on the user’s request.</p>
        <p>So, the proposed approach uses IMRAD to collect and process the data with ontologies. In
this way, the ontologies are constructed not by the specific structure of each work but by the
generally accepted IMRAD structure. The parent node will be a specific area set to which

the study belongs ( = ∑︀ , where  – specific area of set of  ). The  node is

linked with ,  , ,  nodes (representing IMRAD). Each IMRAD node is linked with the
specific IMRAD type node (such as ammonia determination by Nessler’s method (for methods)
or “chicken manure” or “glycerine” (for subjects)). And each specific IMRAD type node is linked
with leaf nodes of ontology – specific studies where such entities were used.</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Structuring several works simultaneously using an ontological graph</title>
        <p>To demonstrate the capabilities of the proposed ontological system, scientific works on anaerobic
digestion were chosen. The general view of the resulting graph is shown in figure 3.</p>
        <p>The root node of the resulting graph is the “Scientific reports” node. In its structure, the
ontological graph is complex because it has additional branches from child nodes. Child nodes
are: “Reports on biotechnology” and “Reports on anaerobic digestion.” From the child node
“Reports on anaerobic digestion” are going the central sub-leaf nodes that reflect the basic
principle of systematization of scientific works: “Results,” “Materials and methods,” “References”.
This basic principle is shown in figure 4. A separate node of Main Metadata was also additionally
created. This node contains the central metadata: object, subject of study; practical significance,
the scientific novelty of study; hypotheses; keywords; abstract, conclusions.</p>
        <p>The entire sequence and principle of filling and maintenance of data by users in the received
ontology are shown in the Workflow diagram (figure 5).</p>
        <p>The child nodes of each of these systematizing ontological nodes are the scientific works
themselves. Each data block is in the form of separate attributes of the ontological node. This
solution allows you to use all the information processing tools of the CIT Polyhedron system. In
particular, such tools are both general (for example, filtering) and specialized, such as ranking
and auditing. An example of filtering is shown in figure 6.</p>
      </sec>
      <sec id="sec-3-3">
        <title>3.3. Application of ranking mechanism in the structuring of scientific works</title>
        <p>
          All attributes can be used to rank information using the “Alternative module” described in
previous works [
          <xref ref-type="bibr" rid="ref18 ref29">18, 29</xref>
          ]. Each nodes attributes is filled with numeric, textual, and/or mixed
types of data. The following attributes are filled with text data: “References”, “Methods for
Quantitative Analysis”, “Materials for researching”, “Thermophilic”, “Chicken manure
substrate”, “Spectrophotometer parameters of the experiment”, “The actual rate of reproduction of
”, “Keywords”, “Glassware”, “Reagents”, “Equipment”, “Object ”, “Subject of study”, “The aim of
the study”, “Chicken”. Numeric data contains the following attributes: “Initial pH”, “Methane
content, % Vol.”, “pH of obtained solid product”, “Ammonium nitrogen concentration, mg/L”,
“The concentration of volatile fatty acids (VFA) mg/L”, “The dry matter content, %”, “The ash
content, %”. The attribute “The native moisture content of the substrate” contains mixed-type
        </p>
      </sec>
      <sec id="sec-3-4">
        <title>3.4. Application of the audit mechanism in structuring scientific works</title>
        <p>
          Users can also use the specialized audit module described in previous works [
          <xref ref-type="bibr" rid="ref15 ref16 ref17 ref29">15, 16, 17, 29</xref>
          ]
for all attributes. The graph “Standard” is the ontology itself, containing works that will be
supplemented and expanded. This solution will allow users to automatically check whether
there is a particular work in the database. Also, this solution will allow checking the hypotheses
for compliance with already completed studies. Also, the audit module will allow users to
compare an existing METADATA and attributes that are available in ontology at the same time.
In particular, these attributes are the materials and methods of the results and the list of sources.
Results that do not match the attributes of the “standard” ontology emphasize red. An example
        </p>
        <p>Main results (list of ontological nodes)
Initial pH Absolute Development of a rational way for utilization of meta-tank waste at JSC
(type of data “Vasylkivska poultry farm”, Titrimetry, Methane tank, Development a method
are numbers) for utilization of methane tank efluent Methods for Quantitative Analysis,</p>
        <p>Materials for researching, Abstract
Methane con- Absolute Development a method for utilization of methane tank efluent, Development
tent, % Vol. of a rational way for utilization of meta-tank waste at JSC “Vasylkivska
(type of data poultry farm, Methods for Quantitative Analisis, Materials for researching,
are numbers) Abstract
The ash con- Absolute Development of a rational way for utilization of meta-tank waste at JSC
tent, % “Vasylkivska poultry farm, Development a method for utilization of methane
tank efluent, Methods for Quantitative Analisis, Materials for researching,</p>
        <p>Equipment, Reagents, Thermophilic, Chicken manure substrate
The dry mat- Absolute Development a method for utilization of methane tank efluent, Development
ter content, % of a rational way for utilization of meta-tank waste at JSC “Vasylkivska
poultry farm Keywords, Methods for Quantitative, Analysis, Materials for
researching, Equipment, Thermophilic Chicken manure substrate
of an audit fragment is shown in figure 9.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Discussion and conclusions</title>
      <p>We have proposed to use IMRAD as the main approach to structure the articles in the form of a
semantic ontology. As a proof of the concept, we have implemented a universal ontological
solution that can provide systematization and structuration of any scientific studies. “Polyhedron” is
not a reference manager like “Endnote”, “Mendeley”, and it is also not a scientometric database,
but in the nearest perspective, it‘s possible to convert our technology into a useful analogue.
But, the advantages and potential scenarios for usage of our solution have been demonstrated by
the example of biogas studies. The potential of using ranking and auditing tools in the obtained
ontological database has been also shown. Numeric and semantic characteristics were separated
from the main text and used to process by specialized algorithms of IT Platform Polyhedron.
For example, users can find studies where specific method was used by both, using the structure
and filtering of studies data. The numeric data of studies are processed by the ranking tool that
assigns ranks to nodes depending on the value of these numeric characteristics. The created
ontology allows to obtain the structured set of studies, separate their characteristics, provide
the possibility to view all of the methods, measured parameters in the view of node and use
them to find the studies where they were used. The detailed comparison of our ontological
solution with most common analogues is presented on the table 2 below.
Automatic extraction of the information Present
from any added PDFs
Tags, keywords, or search the full text of Present
most PDFs functions.</p>
      <p>Ability to cite articles in word/pages Absent
Ability to use numeric data of the articles Present
for ranking
Accentuation of important semantic char- Present
acteristics for management of the wide
range of articles
Ability to compare diferent articles Present
Visualization of the information Present
Usage of IMRAD approach to sort articles Present</p>
      <p>* proposed approach using CIT “Polyhedron”</p>
      <p>As we can see from the table above, our ontological solution has all of the basic functions
of the most common software. Our solution can be used as a bibliographic software and as a
scientometric database. In addition, our solution could provide such functions as ranking based
on specific attributes, ability to compare diferent articles, visualization of the information in
view of an ontological tree or “ontocubes” and usage of IMRAD approach to sort articles.</p>
      <p>Present
Present
Present
Absent
Absent</p>
      <p>Present
Present
Present
Absent
Absent</p>
      <p>Scopus
Absent
Present
Absent
Absent
Absent</p>
      <p>Google
Scholar
Absent
Present
Absent
Absent</p>
      <p>Absent
Absent</p>
      <p>Absent
Absent</p>
      <p>Absent</p>
      <p>Absent
Absent</p>
      <p>Absent</p>
      <p>Absent
Absent</p>
      <p>Absent</p>
      <p>Absent
Absent</p>
    </sec>
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