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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Scientific journal NPU named after M.P. Drahomanov</journal-title>
      </journal-title-group>
      <issn pub-type="ppub">0360-1315</issn>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.34142/HSR.2018.04.04</article-id>
      <title-group>
        <article-title>Intelligent Decision Support Agent Based on Fuzzy Logic in Athletes' Adaptive E-Learning Systems</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Yaroslav Hnatchuk</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Cherednichenko</string-name>
          <email>olha.cherednichenko@gmail.com</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Hnatchuk</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pityn</string-name>
          <email>pityn7@gmail.com</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Hlukhov</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Kherson State University</institution>
          ,
          <addr-line>University str., 27, 73000, Kherson</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Khmelnytskyi National University</institution>
          ,
          <addr-line>Instytuts'ka str., 11, Khmelnitskyi, 29016</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Lviv State University of Physical Culture named after Ivan Boberskyj</institution>
          ,
          <addr-line>Kostiushka str., 11, Lviv, 7900</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>National Technical University “Kharkiv Polytechnic Institute”</institution>
          ,
          <addr-line>Kyrpychova str., 2, Kharkiv, 61002</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <volume>4</volume>
      <issue>4</issue>
      <fpage>139</fpage>
      <lpage>144</lpage>
      <abstract>
        <p>Currently in Ukraine there is a need to design and develop adaptive e-learning systems for theoretical and tactical training of athletes in the chosen sport. The developed user profile model, which combines both individual user parameters and user actions in the system, allows to take into account all qualitative and quantitative information about the user without losses. Developed rules and method of intellectual agent to support decision making to provide adaptive learning content based on fuzzy logic provide efficiency in the formation and development of logical, associative, tactical thinking, improving the tactical and theoretical training of athletes. Such rules and method formalize the decision making process for the provision of adaptive learning content and are the theoretical basis for the development and design of adaptive e-learning systems for theoretical and tactical training of athletes in the chosen sport.</p>
      </abstract>
      <kwd-group>
        <kwd>1 Intelligent agent</kwd>
        <kwd>adaptive e-learning systems</kwd>
        <kwd>fuzzy logic</kwd>
        <kwd>decision support</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <sec id="sec-1-1">
        <title>The modern system of sports training is a complex system characterized by progressive principles,</title>
        <p>
          a wide range of interdependent tasks scientifically substantiated selection of means and methods,
perspective long-term planning, high organization of control, maintenance of hygienic conditions, etc.
[
          <xref ref-type="bibr" rid="ref1">1</xref>
          ]. Sports training is carried out for individual sections, which have independent features, namely the
aspects of training: physical, technical, tactical, theoretical, moral and volitional and integral [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ].
        </p>
      </sec>
      <sec id="sec-1-2">
        <title>Theoretical and tactical training of athletes is one of the leading places in the current process, in this regard, the planning of the training process of athletes, which allows more systematic selection of tools and methods of training, as well as to determine criteria for monitoring the level of training of athletes.</title>
      </sec>
      <sec id="sec-1-3">
        <title>Today's realities in the context of the COVID-19 pandemic have made adjustments in the planning and conduct of theoretical and tactical training of athletes. Therefore, the use of information technology in the training of athletes is relevant today.</title>
      </sec>
      <sec id="sec-1-4">
        <title>The use of information technology allows for the training of athletes in compliance with all quarantine requirements. In the system of training athletes, much attention is paid to the use of information technology.</title>
      </sec>
      <sec id="sec-1-5">
        <title>But the vast majority of domestic works are devoted to the review, prospects of application and</title>
        <p>
          opportunities that can provide information technology in the system of training athletes. Foreign
experts pay more attention to the personal assistants of the athlete, who allow by measuring and
calculating certain parameters, to provide recommendations for physical training. Thus, in [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ] the
authors propose a digital coach for skiers, which improves the technique of skiing.
        </p>
      </sec>
      <sec id="sec-1-6">
        <title>In the article [6] the authors consider personal assistants for amateur athletes and elite athletes who help athletes improve their physical fitness.</title>
      </sec>
      <sec id="sec-1-7">
        <title>In [7] the author investigates the use of associative mining rules to control the physical training of athletes, which allows to identify the features of physical fitness and the main factors that affect this process.</title>
      </sec>
      <sec id="sec-1-8">
        <title>The work [8] is devoted to the analysis of the relationship between the physical capabilities of</title>
        <p>
          athletes and technical and tactical capabilities based on data mining. The study [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] is devoted to
assessing the physical fitness of taekwondo athletes using multi-agent systems.
        </p>
      </sec>
      <sec id="sec-1-9">
        <title>In [10] the authors investigated the use of virtual reality in the system of training and competitive activities of athletes. From the review it can be concluded that the vast majority of research is aimed at using information technology to monitor the physical fitness of athletes, their competitive activities and assistance to coaches.</title>
      </sec>
      <sec id="sec-1-10">
        <title>If we talk about the theoretical and tactical training of athletes, the vast majority of domestic</title>
        <p>research suggests either the use of multimedia and cloud technologies for such training [11, 12] or the
use of computer training and control programs in physical education and sports. It is proved in the
works that student-athletes who studied with the use of computer programs mastered the material
better and more successfully than those student-athletes who practiced without their use.</p>
      </sec>
      <sec id="sec-1-11">
        <title>As an effective tool for theoretical and tactical training of athletes, the authors propose the use of an adaptive intelligent e-learning system.</title>
      </sec>
      <sec id="sec-1-12">
        <title>Any educational platform aims to provide users with the necessary information to increase their</title>
        <p>active knowledge of a particular subject area. However, the learning process is a variable that depends
on previous knowledge, motivation and individual needs of users [14].</p>
      </sec>
      <sec id="sec-1-13">
        <title>This raises the question of the importance of developing an adaptive system that takes into account the effective process of learning and acquiring knowledge.</title>
      </sec>
      <sec id="sec-1-14">
        <title>The development of learning materials and their availability on the Internet is insufficient, more importantly, the knowledge materials must be adapted to different characteristics of users, such as their learning style.</title>
      </sec>
      <sec id="sec-1-15">
        <title>Existing e-learning systems are designed to prepare students in relevant specialties, such as 017</title>
      </sec>
      <sec id="sec-1-16">
        <title>Physical Education and Sports, contain in the courses general information about sports, features of</title>
        <p>techniques and tactics and provide an opportunity to test student’s knowledge in the form of tests. In
the system of theoretical and tactical training of athletes, such a generalized approach is insufficient.</p>
      </sec>
      <sec id="sec-1-17">
        <title>According to the literature review, none of the known e-learning systems is designed for theoretical and tactical training of athletes in the chosen sport.</title>
      </sec>
      <sec id="sec-1-18">
        <title>To increase efficiency in the formation and development of logical, associative, tactical thinking,</title>
        <p>improving tactical and theoretical training of athletes based on the formation of special knowledge
about tactics, types of technical and tactical actions, competition rules, history of various sports
(martial arts, cyclic sports, sports games), it is necessary to take into account the level of training of
the athlete, his abilities and capabilities. This work is devoted to solving this urgent problem.</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>2. User profile model and construction of training material profile</title>
      <sec id="sec-2-1">
        <title>In adaptive e-learning systems, such a concept as the system user model is widely used [15]. A user model is a set of specific user parameters [16].</title>
      </sec>
      <sec id="sec-2-2">
        <title>The difference between the concepts of «user model» and «user profile» are considered in the</title>
        <p>works of the authors [17]. The user profile is preferably considered as a set of certain information
about the user, such as skills, cognition, preferences, features of interaction with the system, and the
user model is seen as the goal of knowledge, which includes user actions. In conclusion, we can say
that the user model is an abstract view of the individual differences of users.</p>
      </sec>
      <sec id="sec-2-3">
        <title>In this paper, the authors propose the concept of «user profile model», which combines both individual user parameters and user actions in the system.</title>
      </sec>
      <sec id="sec-2-4">
        <title>The user profile model is represented by a set (1):</title>
        <p>where IPK – set containing the athlete's personal information;</p>
      </sec>
      <sec id="sec-2-5">
        <title>DK – set that characterizes the activities of users in the system.</title>
        <p>where OI – set containing the athlete's personal information;</p>
      </sec>
      <sec id="sec-2-6">
        <title>MS – methods of perception of educational material;</title>
      </sec>
      <sec id="sec-2-7">
        <title>LS – learning style; Y – progress (number of passed levels in the system).</title>
        <p>= {</p>
        <p>,   },
= { , 
,  ,  },
The set that characterizes the activities of users in the system is represented by a formula:</p>
        <p>= { ,  ,  ,  },
where kr – number of completed thematic sections;
kg – number of games played;
kt – number of tests passed;
kp – number of points scored in games.</p>
        <p>The set containing the athlete's personal information is described by a formula (4):</p>
      </sec>
      <sec id="sec-2-8">
        <title>The information contained in the user profile model is not only quantitative but also qualitative,</title>
        <p>the best solution for its processing will be the use of fuzzy logic. Mamdani’s method was chosen as a
fuzzy conclusion [18]. According to the</p>
        <p>Mamdani’s
method for decision
making quantitative
variables are translated into linguistic terms by phasing and then operations with them are carried out
as with qualitative indicators. After that, a knowledge base is built, which contains fuzzy production
rules of the form:
  =   1   1 
…      
…      
      ,
where   – production rule,  = 1 …  ,</p>
        <p>- number of rules;
where sn – surname;
nm – name;
vs – kind of sport;
sr – sports categories.
where pr – practice;
tpr - first theory then practice;
trtpr - theory together practice;
tt – theory.
where vz – visual;
kn – kinesthetic;
ay – audible;
vr – verbal;
lg – logic;
sc – social;
sp – separated.</p>
        <p>= { , 
,</p>
        <p>,  },</p>
        <p>= { ,   ,  ,   ,  ,  ,   },</p>
      </sec>
      <sec id="sec-2-9">
        <title>A set representing the methods of perception of educational material:</title>
      </sec>
      <sec id="sec-2-10">
        <title>A set representing the learning style is described by a formula (6):</title>
        <p>− input parameters,  = 1 …  ,  − number of input parameters,   = {  };
  − fuzzy variable (term of a linguistic variable);
  – output parameters,  = 1 …  ,  – number of output parameters;
  – consequence of the rule.</p>
      </sec>
      <sec id="sec-2-11">
        <title>An important aspect in providing adapted content is to build a profile of educational material. The</title>
        <p>profile of the training material is assigned a weight according to the level of theoretical and tactical
material contained in the profile. The values of the weights are distributed as follows:  = 1 – low
level,  = 2 – medium level,  = 3 – high level.</p>
      </sec>
      <sec id="sec-2-12">
        <title>Processing of qualitative and quantitative information can be carried out using a fuzzy logic device, intelligent agents or neural networks [19]. A combination of these technologies is also often used to increase the efficiency of information processing.</title>
      </sec>
      <sec id="sec-2-13">
        <title>The use of an intelligent agent in complex systems allows you to partially eliminate human</title>
        <p>participation in the processing of information, avoid the loss of important information, minimize
errors in the processing of large amounts of information [20].</p>
        <p>Intelligent agents are widely used in various applications. In the article [21] is intended to provide
a practical decision support system framework, based on multi agent system and intuitionistic fuzzy
logic, useful for implementation in the healthcare area. The process of starts with the determination of
the linguistic variables afforded by the medical experts’ caregivers of intensive therapy. Then, the
building of the rules base, with regard to the citied above steps, is realized by the assist of medical
expert knowledge. Thereafter, the expert agent calculates membership degree, nonmembership
degree, and hesitation margin to determine the degree of risk. Finally, the expert agent transmits the
output variable (normal, large, and high) to the doctor agent to provide the suitable treatments to the
patient.</p>
      </sec>
      <sec id="sec-2-14">
        <title>The paper [22] focuses on introducing the concept of fuzzy agent: a classical architecture of agent</title>
        <p>is redefined according to a fuzzy perspective. A pedagogical illustration of fuzzy agentification of a
smart watering system is then proposed. Authors presented a model of fuzzy agents proposed for the
modelling and design of complex systems (intelligent/smart systems, distributed systems, cooperative
systems, assistance systems, etc.), where uncertainty and imprecision are considered.</p>
      </sec>
      <sec id="sec-2-15">
        <title>The approach to the development of intelligent decision support systems using ontology knowledge bases consisting of such systems in the article [23] is considered. An adaptive ontology is proposed to define as an ontology with concepts and relations weighted according to its importance for a given subject domain.</title>
        <p>In study [24], a novel intelligent-agent-based fuzzy group decision making model is proposed as
an effective multicriteria decision analysis tool for credit risk evaluation. In this proposed model,
some artificial intelligent techniques, which are used as intelligent agents, are first used to analyze and
evaluate the risk levels of credit applicants over a set of pre-defined criteria. Then these evaluation
results, generated by different intelligent agents, are fuzzified into some fuzzy opinions on credit risk
level of applicants. Finally, these fuzzification opinions are aggregated into a group consensus and
meantime the fuzzy aggregated consensus is defuzzified into a crisp aggregated value to support final
decision for decision-makers of credit-granting institutions.</p>
      </sec>
      <sec id="sec-2-16">
        <title>The study [25] introduces a novel mobile agent-based cross-layer anomaly detection scheme,</title>
        <p>which takes into account stochastic variability in cross-layer data obtained from received data packets,
and defines fuzzy logic-based soft boundaries to characterize behavior of sensor nodes. This
crosslayer design approach empowers the proposed scheme to detect both node and link anomalies, and
also effectively transmits mobile agents by considering the communication link-state before
transmission of the mobile agent.</p>
      </sec>
      <sec id="sec-2-17">
        <title>Thus, intelligent agents are good at solving a variety of problems, especially when combining</title>
        <p>different technologies. Given that adaptive e-learning systems need to process different volumes and
types of information, both quantitative and qualitative, in this paper, the authors propose the use of an
intelligent agent for the decision-making process in adaptive e-learning systems for athletes.</p>
      </sec>
      <sec id="sec-2-18">
        <title>The decision making process of an intelligent agent is based on the analysis of a fuzzy logical conclusion. The result of the agent's work will be a decision to provide the athlete with adapted training content.</title>
      </sec>
      <sec id="sec-2-19">
        <title>The structure of the intelligent decision support agent based on fuzzy logic in athletes’ adaptive elearning systems is represented on Fig.1.</title>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Method of activity of intelligent agent for support of decision making</title>
      <sec id="sec-3-1">
        <title>The intelligent agent models the decision-making process based on fuzzy production rules.</title>
      </sec>
      <sec id="sec-3-2">
        <title>The intelligent agent takes into account the previous experience of the player, analyzing the model</title>
        <p>of his profile and the profile of the training material.</p>
        <p>The method of decision support by an intelligent agent to provide adaptive content to the athlete
consists of the following steps:
• the user profile is analyzed in a set of production rules to support decision-making on the
possibility of providing adaptive content, the consequence of each rule is checked, according to
which the counter is counted d;
• the profile of training material is analyzed, which contains materials on theoretical and tactical
training of athletes, which are divided into appropriate levels;
• if the value of the counter is  &lt; 10, then adapted content is provided, where the weight of the
profile of the training material  = 1, that is low level;
• if the value of the counter 10 ≤  &lt; 15, then the adapted content is provided, where the weight
of the profile of the training material  = 2, that is the middle level;
• if the value of the counter is  ≥ 15, then adapted content is provided, where the weight of the
training material profile is  = 3, that is a high level.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Experiment</title>
      <p>As an example, consider how an intellectual agent forms a conclusion about providing an athlete
with adapted educational content. Consider the following rules:
 5 =    4 
 6 =    6 
 7 =    8 
 8 =    10 
 9 =    10 
  6 
  6 
  7 
  7 
  8 
  4 
  5 
  7 
  9 
  10 
 10 =    12 
  8</p>
      <p>12 
 11 =    12 
 12 =    13 
 13 =    12 
  10 
  11 
  9</p>
      <p>After analyzing the above rules, the intelligent agent calculates the value of the counter, which for
low level is 4, for middle level is 4, for high level is 5. Thus, after analyzing all the rules of the
knowledge base, built for a particular athlete, the final value of the counter d is obtained, according to
which the adapted content is provided. If the value of the counter is d&lt;10, then adapted content is
provided, where the weight of the profile of the training material p=1, that is low level. If the value of
the counter 10≤d&lt;15, then the adapted content is provided, where the weight of the profile of the
training material p=2, that is the middle level. If the value of the counter is d≥15, then adapted content
is provided, where the weight of the training material profile is p=3, that is a high level. If the
knowledge base does not have enough rules for analysis to form the value of the counter, then the
training content is provided at a lower level.</p>
      <sec id="sec-4-1">
        <title>Two experimental groups were used as an experiment in the effectiveness of using an intelligent agent to support decision making in adaptive learning systems. The first group was engaged in conventional systems without the use of an intelligent agent, the second - with the use.</title>
      </sec>
      <sec id="sec-4-2">
        <title>At the beginning, both groups underwent initial testing. The first group could independently</title>
        <p>choose the order of topics to study, as well as the level of the game to test knowledge. After that, both
groups passed the final test to check the level of knowledge. As the analysis of the results showed, the
players of the first group did not always assess their level correctly, there were repetitions in the test
tasks, the transition to the next level of the game was carried out by the player, that is there was a lack
of system, which led to low quality knowledge.</p>
      </sec>
      <sec id="sec-4-3">
        <title>The second experimental group used an intelligent agent in their training, who analyzed the user</title>
        <p>profile and the training material file and suggested, depending on the results of the profile analysis,
the transition to the next level or repetition of the material where the lowest number of points was
scored. As a result of the final tests, the players of the second group showed a higher and systematic
level of knowledge of tactics and techniques of a particular sport.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Conclusions</title>
      <p>Currently in Ukraine there is a need to design and develop adaptive e-learning systems for
theoretical and tactical training of athletes in the chosen sport. The developed user profile model,
which combines both individual user parameters and user actions in the system, allows to take into
account all qualitative and quantitative information about the user without losses. Developed rules and
method of intellectual agent to support decision making to provide adaptive learning content based on
fuzzy logic provide efficiency in the formation and development of logical, associative, tactical
thinking, improving the tactical and theoretical training of athletes.</p>
      <p>Such rules and method formalize the decision making process for the provision of adaptive
learning content and are the theoretical basis for the development and design of adaptive e-learning
systems for theoretical and tactical training of athletes in the chosen sport.
6. Reference</p>
    </sec>
  </body>
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