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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Method for Determining Information Proximity Based on Spectral Conversion of Text Documents</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Maria A. Butakova</string-name>
          <email>butakova@rgups.ru</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Andrey V. Chernov</string-name>
          <email>avcher@rgups.ru</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Grigorii S. Miziukov</string-name>
          <email>mgs_cmko@rgups.ru</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Center of monitoring, quality education, Rostov, State Transport University</institution>
          ,
          <addr-line>Rostov-on-Don</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Dean, Rostov State, Transport University</institution>
          ,
          <addr-line>Rostov-on-Don</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Department of Computer, Engineering and Automated</institution>
          ,
          <addr-line>Control Systems, Rostov</addr-line>
          ,
          <institution>State Transport University</institution>
          ,
          <addr-line>Rostov-on-Don</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>1</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>The process of identifying key information in
unstructured sets of textual information is
complex and multiple-aspect. In this regard
various methods and technologies are being
actively developed that can improve the
analysis process and reduce the gap between
the quality of the obtained results and the
computational resources required for the
analysis. This article provides an example of
an alternative method for determining
information proximity in large arrays of
textual information. A distinctive feature of
this method is the application of spectral
conversion of the information and means of
descriptive logic for the logical inference of
analysis results of the text documents array.
The main components of the method as well
as conditions and statements of the logical
inference of the analysis results are
considered. The analysis of the obtained
results based on the results of the approbation
of the method is given. The obtained results
clearly demonstrate the possibility of
applying the method for semantic
classification problems in information
decision-making systems.</p>
    </sec>
    <sec id="sec-2">
      <title>1 Introduction</title>
      <p>In the context of the current trend of digitalization of
various aspects of knowledge domain large amounts of
information of different structure are accumulated. The
predominant type in these arrays is unstructured
information presented in the form of multiple
multimedia and text files of different formats and
linguistic affiliation. Intelligent analysis technologies
are used to analyze these types of information [Lij10,
Jia14]. Intelligent analysis is a complex of
interdisciplinary links by means of which a basic
model is built up that in future serves as a basis for
application of various methods. The most commonly
used methods are classification, prediction, clustering,
association and time series modelling. However,
semantic analysis is considered to be an important task
within the framework of intelligent analysis of text
data [Sar19]. Although there are multiple solutions and
approaches in the field of semantic analysis of textual
information, not all of them are able to fully provide a
qualitative analysis process since there are a number of
problems primarily related to the identification of
semantic links between the analyzed objects. It is also
worth noting the distinctive feature of unstructured
information from structured or semistructured one
which implies that this type of information does not
have a structure that describes the stored data, and it
has anthropogenic character. Such an abundance of
heterogeneous information results in the need to apply
combinations of several different methods to achieve
the desired result. Therefore, this article proposes a
method for determining information proximity in large
arrays of text information, the distinctive feature of
which is the use of spectral conversion of information
and means of descriptive logic for the logical inference
of the result of analysis of text documents array to
classify emerging situations and identify redundancy in
large arrays of text information. The article is arranged
as follows. Section 2 includes information on currently
available scientific studies in the selected field. Section
3 describes the proposed method. The main variables
of the method, functions, as well as conditions and
statements which the logical inference of the results is
based on are also considered in the section. Section 4
describes the results of testing the method. Section 5
describes further scientific application of the method.
Section 6 concludes the article.</p>
    </sec>
    <sec id="sec-3">
      <title>2 Previous Work</title>
      <p>The issue of determining information proximity in
large arrays of unstructured textual information, for
instance, the approach to semantic classification
[Bou14, Ma16] is of particular interest for scientific
research. Currently, there are a large number of
different methods and technologies used to analyze text
information. Among the methods one can distinguish
the method of extracting knowledge from information,
methods of searching for information in coherent texts,
clustering, classification and summarization [Tan19].
“Big Data” technology is the most promising and
actively developing technology [Fad18, Ous17].
However, despite the constant development of these
approaches there are difficulties that to one degree or
another impede the qualitative analysis of textual
information. In the article [Jus18] the author considers
some of the most frequently encountered difficulties
while analyzing .textual information. Particular
attention should be paid to the methods of classifying
and determining the information proximity between
text documents. The most interesting approaches for
solving problems in this area are presented in articles
[Zha14, Fis08]. In the article [Zha14] the authors
propose an approach based on the calculation of the
semantic similarity of short texts through
languagebased network and word semantics. In [Fis08] the
authors propose a group of auxiliary methods for
determining the informational proximity and texts
classification that supplement the formed semantic
model with structural information for classification.
The following sections propose an alternative approach
for determining information proximity and semantic
classification of texts based on spectral conversion of
information and logical inference by means of
descriptive logic.</p>
    </sec>
    <sec id="sec-4">
      <title>3 Proposed Method</title>
      <p>The process of determining the information proximity
between the analyzed objects in large arrays of text
information involves the identification of similar
intersection points on the basis of which one can make
an assumption about the information proximity of two
objects. However, this process also determines the
unique properties of the objects of analysis that act as
preventive condition and do not allow to refer the
objects of analysis to one category by the primary
features thereby making the process of determining the
information proximity more qualitative and effective.
Thus, while designing the method the following tasks
were set:
1. To identify common and unique properties of
objects of analysis. In this case, this is the definition of
common and unique lexical units in the text
information flow in the process of analysis.
2. To form the structure of representation of the
identified lexical units.
3. To determine the information proximity between the
objects of analysis under the condition that the
structures of the identified lexical units may be the
same but the objects of analysis belong to different
categories; the structures may be different but the
objects belong to the same category.</p>
      <p>To solve the above-mentioned problems we
propose a method for determining the information
proximity in text arrays of information based on the
methods of spectral representation of information
[Vas17, God77] and methods of logical inference by
means of descriptive logic [Kri18]. The application of
the spectral approach to the representation of textual
information is determined by the high efficiency of the
calculation process due to the operation with numerical
values in the analysis process. Means of descriptive
logic act as the main mechanism (the core of the
method) that based on formulated statements
determines the information proximity between the
objects of analysis by logical inference.
Conventionally, the method can be divided into three
components. The first component of the method
describes sets and basic functions performed after
initialization of all objects. The second part is
responsible for the process of spectral analysis and
obtaining spectra of the analyzed objects. The final part
is a set of criteria and statements of descriptive logic.</p>
      <p>The process of determining information proximity
begins with the initialization of all objects represented
as a set of unstructured text documents D = {d1, d2,...,
dn}, where dn is a text document. In turn, each dn
element of the set D is a set of lexical units L = {l1,
l2,..., ln}, where ln is a lexical unit. The totality of
lexical units of the set L forms meaningful semantic
connections identifying the context K of each dn
element of the set D. Thus, the objects D, L and K are
initialized at the first stage of the method and
afterwards the performing of the functions
ReBuildTextStruct() and Intersection() is followed. The
purpose of ReBuildTextStruct() function consists of
primary structuring of the set of lexical units and
obtaining the data model as a set of “key-value” pairs.
This is followed by the performing of Intersection ()
function that returns the data dictionary – φ containing
the same elements that are part of the primary data
model obtained by Re-BuildTextStruct() function.
Below there is an example of an algorithm fragment
responsible for initializing and performing the first two
functions.
 ← ∅
 ← ∆%
for each instance  ∈  do</p>
      <p>A
2345(7) ←
(),
where 2345(7) =
2345(7)BC, … , 2345(7)BF; 2345(7)HC, … ,
2345(7)HF
2345(7)BF: 2345(7)HF
function interpretation ():

← 
∗  { ?  7WXYZ[XY\F. ?  7^_`a[? . 
{ ?  7WhY`i ? . ?  7^_`a[ ?  }
end for
for each instance  ∈  do
for each instance  ∈ 2345(7)
do
 ← (, ), where
(, ) query that checks
l ∩ l ≠ ∅
J ⇒
end for
end for
interpretation of the
(, ):
 ← .  o → oY ⋀ r
→ rY.  rY
= 7. ()
function
The initial data preparation is followed by the spectral
conversion stage. The method of singular
transformation was chosen as the main approach for
obtaining the spectrum of information and its detailed
operation can be found in the articles [Miz18, Mal19].
At this stage two functions are performed:
GetAdjacencyMatrix() and SVD().The result of this
stage is to obtain eigenvalues that in the terminology of
spectral theory represent the spectrum of the analyzed
data object of set D. A fragment of the second part of
the algorithm is presented below.
for each instance  ∈ 2345(7) do
t%u ← ()
uxyz ← (t%u), где SVD() – a method of
singular transformation; uxyz – singular values
{uxyz{ , uxyz|, … , uxyzl}
end for
The final step in the method is performing the
IsSumilar () function that returns the result – ψ, which
contains the response on the informational proximity
between the objects of analysis. The Is Similar ()
function is a set of conditions for the feasibility of the
process of determining the information proximity
between the objects and a set of statements suggesting
the possibility of information proximity between the
objects. Below the final fragment of the algorithm is
given that includes a description of the IsSumilar ()
function.
 ← (uxyz, )
Interpretation of the function IsSimilar():
 =  ∪ , where K – knowledge base; T – Tbox, A –
Abox.</p>
      <p>Conditions for IsSimilar() function feasibility:
1. Termination. For any (uxyz, , ) function Θ
gives a response (uxyz, φ, ) in finite amount of
time , where m–uxyzBх uxyzH = {(, ℎ) ∣  ∈
uxyzB, ℎ ∈ uxyzH ⋀ φB х φH = {(, ) ∣  ∈
uxyz, φ
φB,  ∈ φH}.
2. Correctness. For any(uxyz, φ, ), if concepts
are feasible relative to T, then
Θ uxyz, φ,  = 1.
3. Completeness. For
any
(uxyz, φ, ),
if
Θ uxyz, φ,  = 1, then concepts uxyz, φ are
feasible relative to T.</p>
      <p>Feasibility conditions 2 and 3 come to () =
⊤,   ⊨ ⊤
⊥,   ⊭ ⊤
Statements:
uxyzB, uxyzH
and
terminology  there is a concept uxyzH ⊆ uxyzB,
that is  ⊨ uxyzH ≡ uxyzB ⇔  ⊨ uxyzH ⊆
uxyzB и  ⊨ uxyzB ⊆ uxyzH и ⊨ φH ⊆ φB.
2. There is at least one individual 5zxyz such that
belongs to the concept uxyzB ⇔ ∃5zxyz ∈
uxyzB, that is  ⊨ 5zxyz : uxyzB ⇔ (,  ∪
5zxyz : uxyzB).</p>
      <p>For the concept φ the statements will be similar.
Thus, if the statement 2 = ⊤, then the statement 1 = ⊤,
that is there is such an interpretation  = (∆,∙), for
which  ⊨ 5zxyz : uxyzB.</p>
      <p>The proof of statements is reduced to the following
rules:
1. ∀⃗{⃗ ⊨  ∣ ⃗ ∈ ∆}
2. ∃⃗{⃗ ⊨  ∣ ⃗ ∈ ∆}, где ⃗ = {⃗{ , ⃗|, … , ⃗l} –
singular meanings of the concepts uxyzB и uxyzH
if ⊤</p>
      <p>return ← (bool)similar ⇒ true
else if ⊥</p>
      <p>return ← (bool)not similar ⇒ false
end if</p>
    </sec>
    <sec id="sec-5">
      <title>4 Example and Discussion</title>
      <p>To test the proposed method an array consisting of
more than 10 000 unstructured text documents of
different subject orientation was formed. Each
document in the array had a different extension and
language affiliation. The server of the following
configuration was selected as the test environment:
- CPU'S: 40 * Intel(R) Xeon(R) CPU E5-2690 v2 @
3.00GHz;
- RAM: 257826 Mb.;
- ОS: Ubuntu Server Edition;
- Apache: 2.4.10;
- MySQL: 5.7.21-20;
- Nginx: 1.13.4;
- PHP: 7.3.</p>
      <p>The quality of the obtained results was assessed
according to the following criteria:
- percentage of determining information proximity;
- number of identified classification groups;
- possibility of information proximity at the same
spectrum and context;
- possibility of information proximity at the same
spectrum at a different context;
- possibility of information proximity at the different
spectrum but the same context;
- possibility of information proximity at different
spectrum and context.</p>
      <p>Thus, based on the above-mentioned criteria the results
of the work (Fig. 1, 2) of the proposed method for
determining the information proximity were obtained.
Figure 1 shows the dynamics of determining
information proximity. The diagram shows that the
percentage of information proximity varies from 20%
to 90%, while the average boundary for determining
information proximity is ~ 61%. It is also worth noting
that both curves have the same distribution that
indicates the consistency of the results obtained after
comparing the two operating modes of the algorithm
(statements 1, 2).
Figure 2 shows the final distribution of unstructured
documents array. This distribution shows that 10
highest priority categories were identified according to
the results of the algorithm among which there was a
further classification of the analyzed documents. Each
identified classification group included from 6% to
10% of the documents out of the total number of
contained in the array. Each identified classification
group included from 6% to 10% of the documents from
the total number contained in the array.</p>
    </sec>
    <sec id="sec-6">
      <title>5 Future Research</title>
      <p>The process of determining the information proximity
between the analyzed text documents in large arrays of
information has significant potential in the problems of
semantic classification. The data sets obtained as a
result of testing can be used to build up more
comprehensive thematic dictionaries of the subject
areas that can be used in management decision-making
systems and situational management. In addition, the
process of deriving the results of logical statements can
be accompanied by visualization to reflect the map of
semantic relations between various text documents in
information arrays more fully.</p>
    </sec>
    <sec id="sec-7">
      <title>6 Conclusion</title>
      <p>The article considers a method suggesting an
alternative approach to the problem of determining
information proximity between sets of objects
represented as a set of unstructured text documents.
The obtained results of the experiment show a high
degree of information proximity determining with an
optimal ratio of the execution time of all operations
and the use of computational resources. Based on this
it is proposed to apply this method to problems of
semantic classification in decision-making information
systems to classify emerging situations and identify
redundancy in large arrays of textual information,
thereby reducing the amount of necessary stored
information and response time to an incoming query.
Acknowledgment. The reported study was funded by
the Russian Foundation for Basic Research, according
to the research projects No. 19-01-00246-a,
18-0100402-a.
https://doi.org/10.1109/ICACCS.2019.872854
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WebAccessed 10 Nov 2019</p>
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