<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>O. Yanholenko);</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>ChatBots, Intelligent system, API</institution>
          ,
          <addr-line>Telegram Bot, Android1</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>National Technical University, “Kharkiv Polytechnic Institute”</institution>
          ,
          <addr-line>2, Kyrpychova str., Kharkiv, 61002</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <volume>000</volume>
      <fpage>0</fpage>
      <lpage>0001</lpage>
      <abstract>
        <p>The article analyzes the studies of integrating an intelligent system with a chatbot on the Telegram platform using API. The development of knowledge base models for the intelligent system was carried out using the KARKAS shell (Knowledge Acquisition Relevance Knowledge Accumulation Shell). Different approaches to integrating an intelligent system using the shell and based on the API are considered. In the first approach, the intelligent system inherits a hierarchical functional system and knowledge base filtering using a shell inference engine for the chatbot. In the second approach, the integration of the intelligent system with the chatbot is based on the model of a multi-factor knowledge base and on the development of an API. Also, the model of a multi-factor knowledge base is used to build mobile intelligent systems on the Android platform. Placing the knowledge base on the backend, using the API and a finite state machine allows you to scale the intelligent system, turning it into a distributed intelligent system.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>One of the important areas in the field of intelligent information systems is the problem of providing
online user consultation with these systems [1, 2].</p>
      <p>Various messengers demonstrate a high level of user engagement, compared to all other
applications in other categories. Messengers can be considered as a certain type of browser, and their
chatbots as web applications (with elements of artificial intelligence). Using a chatbot as an
interlocutor gives more opportunities in online consultation for making effective decisions in various
subject areas, such as education, business, medicine, ecology.</p>
      <p>Chatbots are aimed at maintaining a dialogue with the user. Developing software based on
artificial intelligence technologies is quite difficult. For this reason, various prototyping tools are
widely used to show clients how the chatbot will look and behave [3].</p>
      <p>The user interface (UI) connects the service of a computer application and a person. Leading
companies Apple, Google, Microsoft, Amazon, Facebook are actively working on a new generation
of UI. The graphical interface (GUI) is the simplest step towards ease of communication, which is
developing and improving for computer applications. Progress in natural language processing (NLP)
has made it possible to use chatbots ChatGPT and DeepSeek for user dialog tasks. The dialog user
interface is used by popular services Facebook Messenger, WhatsApp, WeChat. Voice user interfaces
(VUI), which use generative models of neural networks, are widely used on smartphones. Voice
interfaces, like chatbots, help save time when solving social user tasks [4,5].</p>
    </sec>
    <sec id="sec-2">
      <title>2. Formulations of the problem</title>
      <p>The purpose of the work is to develop an API (Application Programming Interface) for integrating
an intelligent system with the Telegram chatbot.</p>
      <p>The main modules of intelligent systems are the knowledge base and the inference engine.
Traditional methods of implementing the inference mechanism are reverse, direct, mixed, Bayesian
reasoning chains. The KARKAS (Knowledge Acquisition Relevance Knowledge Accumulation Shell)
shell is used to create knowledge base models [6]. The shell is developed based on the FireMonkey
(FMX) cross-platform framework from Embarcadero, which is designed to create user interfaces. A
feature of the framework is that the application code can be compiled into native code for Windows,
Android and iOS [7,8].</p>
      <p>The first problem is developing an API in the PHP programming language and using it to model
an intelligent system using a finite state machine.</p>
      <p>Various frameworks are used to create mobile intelligent systems: Flutter, Ionic, React Native,
Android Native, Xamarin and others. Due to the asynchronous operation of the Android platform,
the algorithm of the inference mechanism of the intelligent application mainly uses direct and
Bayesian reasoning chains. To solve this problem, a multifactorial representation of the knowledge
base is considered.</p>
      <p>The second problem is the development of an intelligent system model for a mobile application
on the Android platform.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Related works</title>
      <p>In [3] a comparative overview of chatbots for convenience and effective customer service in various
business sectors is given. A taxonomy of chatbots is provided based on the following features:
goalbased chatbot; knowledge-based chatbot; service chatbot; response-based chatbot.</p>
      <p>In [4], a chatbot is developed in such a way as to take advantage of the portability of mobile
devices. The chatbot provides a simple user interface that makes the use of the system easy for each
user. The Python programming language is used to create the chatbot, as well as JSON for data with
predefined templates and responses. The chatbot is trained using data sets of different types. The
script train_chatbot.py is designed to build the model and train the chatbot. Another script chatgui.py
implements the graphical interface of the chatbot.</p>
      <p>In [5], a new method for evaluating a chatbot platform is proposed. Two high-level approaches
to designing chatbot platforms are discussed and compared. For example, WYSIWYG platforms strive
for simplicity, but they may lack some advanced features. The proposed approaches to selecting
chatbots are demonstrated using two businesses as examples: a large bank and a small taxi service.</p>
      <p>The advantages of chatbot include command line interface using user interface elements to
quickly respond to user requests and reduce the cost of social services [9]. Delivery channels for
chatbot systems are developing on web pages and messaging platforms such as Telegram, Facebook
[10].</p>
      <p>The technology underlying the development of chatbots is natural language processing. For
example, the following tools are used to create chatbots: Dialogflow, Microsoft Bot Framework,
Telegram Bot API.</p>
      <p>In [11], a prototype of a chatbot architecture on the Telegram platform is developed, which allows
companies to use LLMs interchangeably. The problem of choosing a suitable LLM for developing a
SaaS chatbot is considered. Only three LLMs are considered in detail, of which ChatGPT seems to be
the best choice.</p>
      <p>In [12], the creation of a chatbot Doctor_Chatbot for predicting the presence of cardiovascular
diseases with the highest possible accuracy and speed is considered.</p>
      <p>In [13], a mobile expert system using the forward chaining method as an inference mechanism
and the confidence coefficient method for determining the diagnostic value of the confidence
probability are considered.</p>
      <p>In [14] the development of a model of an expert decision support system for the Android platform
is presented. The knowledge base of the system is formed by inductive learning methods.</p>
      <p>In [15], a model of an Android mobile medical application for breast cancer diagnosis is proposed.
Machine learning methods are used as an approach to diagnosing this disease.</p>
      <p>The purpose of the study of the article [16] was to design and create an expert system for
screening lung diseases based on Android and early warning of patients’ illnesses using the forward
chain method.</p>
      <p>In [17], the development of a website as an expert system for diagnosing diabetes mellitus is
considered. The forward chaining method is used to find the rules for inference.</p>
      <p>The method used in the study of this expert system [18] is a combination of forward chain
reasoning and confidence coefficients.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Main material</title>
      <sec id="sec-4-1">
        <title>4.1. Developing an API for Telegram chatbot</title>
        <p>The development of a knowledge base for Telegram chatbots and mobile applications on the Android
platform was carried out using the KARKAS shell, which provides tools for developing knowledge
base models [6, 19].</p>
        <p>The integration of the Telegram chatbot with the shell interface mechanism involves the
exchange of information between them without user intervention. As a result of the integration, the
chatbot inherits the hierarchical functional system and filtering of the knowledge base using the
shell inference engine. The scheme for sending and receiving requests for working with Telegram
servers is presented in the article [20]. Since the shell is a monolithic application, the integrated
chatbot is also a monolithic application. Therefore, scaling such a chatbot is quite difficult.</p>
        <p>Figure 1 shows screenshots of the user dialogue interface of the integrated chatbot
@es_info_tech_karkas_bot with a shell.</p>
        <p>Next, we will consider another approach to building a chatbot based on the use of micro services.</p>
        <p>An API is a scalable software interface that allows two applications to communicate with each
other. The first application is hosted on a server, and the second application is hosted, for example,
on the Telegram platform. Cloud technologies use APIs to connect loosely coupled microservices.
For example, an API tells an application what data and messages a microservice needs, and what
results the microservice can provide.</p>
        <p>APIs are created in different languages. For example, RESTful APIs are developed in the following
languages: JavaScript and Node. Js, using different frameworks.</p>
        <p>Let's consider creating an API in PHP for a chatbot on the Telegram platform using webhook
support. Using webhooks allows you to avoid embedding data structures and methods for processing
them into the chatbot code. Therefore, the chatbot business model is based on the exchange of
information in the form of messages between the chatbot and the API.</p>
        <sec id="sec-4-1-1">
          <title>Index.php is the API entry point</title>
          <p>The CONFIG directory contains the config.php file, which includes the knowledge base
credentials for interacting with MySQL and a number of getTelegramRoutes(), getRoutes()
functions for managing the chatbot
The LOADER directory contains the API bootstrap files, which contain the ClassLoader,
Route, and other classes
The DATAKNOWLEDGE directory contains files that interact with the knowledge base
The MODEL directory contains the files: users.php, webstack.php, aws.php, model.php,
expertsystem.php, exam.php, in which the business logic is moved to inherited classes
The CONTROLLER directory contains the main files: the CommanderController.php file,
which contains all the necessary methods for interacting with the chatbot via various menu
items; the TelegramController.php file contains general utility methods for interacting with
the Telegram platform
The knowledge base for the chatbot @itbvp_bot includes the following tables: users contains
information about users, test_ws contains information for testing knowledge on choosing a
web stack, knowledge_hoster contains a knowledge base for an intelligent system for
determining a hoster, test_aws contains information for the test on knowledge of Amazon
technology, test_azure contains information for the test on knowledge of MS Azure
technology, exam contains information for the exam on knowledge of Amazon and MS Azure
technology</p>
          <p>Scenario of user communication with the chatbot using the API: the user sent a request (for
example, /start or selecting the chatbot button) to the API. The CommanderController controller
received the message and, in accordance with the logic of the getTelegramRoutes function from the
config.php file, calls the method from the CommanderController to process the business logic of the
database and sends a message to the chatbot for further user actions. Figure 2 shows screenshots of
user interaction in knowledge testing mode, in exam mode, and in dialogue mode with an intelligent
system for choosing a web stack.</p>
          <p>The model of the intelligent system based on the API is designed as a finite state machine. Using
the finite state machine, you can set the behavior of the system during a dialogue with the user.</p>
          <p>Placing the knowledge base on the backend, using API and state machine allows scaling the
intelligent system, turning it into a distributed intelligent system.</p>
        </sec>
      </sec>
      <sec id="sec-4-2">
        <title>4.2. Mobile intelligent systems on the Android platform</title>
        <p>The choice of a particular technology stack depends on many factors, here are some of them: the
type of web application and its performance, the specialization of team members in specific
technologies, the scope of use of the software product, the size of the software product and the cost
of its development.</p>
        <p>The Android-based mobile intelligence system TECHSTACK [22] can be used to advise users
(project managers, developers, or enterprise technology decision makers) on which technology stack
to choose under certain conditions.</p>
        <p>The classes of the subject area with their hierarchy level are presented in Table 1.</p>
        <p>The monolithic chatbot @es_info_tech_karkas_bot uses a hierarchical functional system. The
chatbot @itbvp_bot and Android-based mobile applications use a multifactor knowledge base model,
in which the main layers (factors) of the knowledge base are highlighted. Screenshots of the dialog
user interface of the TECHSTACK mobile application in knowledge testing mode are shown in
Figure 3.</p>
        <p>Mobile applications with knowledge bases developed using the KARKAS shell are available on
Google Play.</p>
        <p>The intelligent mobile application ES_RFCHD is designed to determine the risk of developing
coronary heart disease (CHD) in a practically healthy person. The relevance of developing a mobile
application is that currently in medicine there is a clearly expressed process of transition to the
concept of CHD prevention, that is, to the concept of risk factors associated with the lifestyle of a
particular patient. The purpose of the application is to recognize the presence of risk factors for CHD
with an emphasis on the individual lifestyle of the patient, using expert knowledge. The features of
the application include the fact that with its help the patient is diagnosed with: type of coronary
behavior, degree of social and psychological support, level of physical activity, degree of adequacy
of rest [23].</p>
        <p>The intelligent mobile application ES_DBT (diagnosis of breast cancer) is designed for early
diagnosis of breast tumors. Diagnosis is based on the knowledge of an expert oncologist. The
knowledge is grouped into the following sections: thermography, anamnesis, physical examination,
echotomography. The application allows classifying the following tumors: lipoma, fibroadenoma,
diffuse fibrocystic mastopathy, localized fibrocystic mastopathy, DFA (diffuse), DFA (localized),
mastitis [24].</p>
        <p>The intelligent mobile application ES_MI helps doctors diagnose patients with heart attacks,
assess their condition and predict the development of complications in myocardial infarction. The
application helps doctors diagnose patients with heart attacks, assess their condition and predict the
development of the following complications in myocardial infarction: fibrillation, acute left
ventricular failure, chronic heart failure, arrhythmia, thromboembolism, myocardial rupture,
recurrent infarction. The inference engine is based on the Bayesian formula. A user consultation
with the ES_MI application with 28 symptoms takes 10 minutes, and with the possibility of an
express consultation (7 symptoms) - 3 minutes [25].</p>
        <p>The intelligent mobile application ES_HEPATIT is designed to diagnose acute and chronic liver
diseases. The application makes it possible to recognize the cause of liver disease and, if possible, to
achieve a therapeutic effect by eliminating it. The application allows for the targeted inclusion of
medications for the treatment of liver diseases and a statistical assessment of therapeutic measures
in patients [26].</p>
        <p>All these mobile applications are designed by recoding the modules of the KARKAS shell and
therefore belong to the class of monolithic applications.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Experiment</title>
      <p>A hoster is a legal entity or individual that provides the opportunity to host a client’s website or
online store on their site using hardware and software.</p>
      <p>When choosing a hosting service, the user usually pays attention to the following indicators:
platforms provided by the hosting service, hosting technology (php, java, asp.net), channel capacity,
hosting options (shared, vps, dedicated), server location, type of company providing hosting, hosting
service country, the possibility of the hosting service providing official documentation, money-back
guarantee, hosting service rental period, the possibility of providing a trial period, the size of the
guaranteed uptime, the number of processors on the site, the availability of backup options provided
by the hosting service, cost, payment terms.</p>
      <p>Let's consider the creation of a prototype of an intelligent mobile application for choosing the
most optimal hosting provider based on certain criteria and conditions.</p>
      <p>The conceptual model of the subject area can be represented as a table, where the columns are
the attributes of the subject area, and the rows are the objects of the subject area. The shell editor
allows you to export a table from Excel and use it to compile lists of attributes and conjunctive rules
of the knowledge base. Next, the cognitive scientist composes questions for the user and attaches
them to the attributes. In this version of ontology construction, one class is allocated, which contains
quite a lot of objects. Such ontology construction can be considered as a preliminary construction.
Next, it is necessary to allocate classes of the subject area in order to reduce the number of rules,
since the inference engine is sensitive to the number of rules.</p>
      <p>Let us present the text of one of the conjunctive rules of the knowledge base.</p>
      <p>Rule 1. Logical condition: A&amp;B&amp;C&amp;D&amp;E&amp;F&amp;G&amp;H&amp;I&amp;J&amp;K&amp;L&amp;M&amp;N#
IF
A Hoster's country = Ukraine
B Country where the hoster's servers are located = Ukraine
C Hoster's type = Company with its own datacenter
D Cost (per month) = Up to 5 dollars
E Hosting rental period = 1 year
F Hosting technology = Opensource (php, mysql, perl)
G Hosting platform = *nix systems
H Disk space = Up to 500 MB
I Required traffic per month = Up to 1 GB
J Uptime guarantee over 99.8% = Yes
K Money-back guarantee = Yes
L Availability of official documentation by the hoster = Yes
M Payment terms = Postal order
N Provision of a trial period = Yes
TO</p>
      <p>Host = hosting.ua.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Discussion</title>
      <p>The KARKAS shell, as a monolithic system, is easy to learn, manage and test. The shell has the
following disadvantage - the implementation of new scaling technologies will require recoding the
entire application. The advantage of the shell is that it allows you to create and debug knowledge
bases.</p>
      <p>Integrating the shell inference engine with the chatbot allows it to inherit the shell's
conversational user interface (Figure 1), which is different from the API-based chatbot's
conversational interface (Figure 2).</p>
      <p>Chatbots: @es_medicine_karkas_bot, @es_test_karkas_bot, @es_economy_karkas_bot,
@es_info_tech_karkas_bot are not scalable. To scale chatbots, they can be placed in threads.</p>
      <p>The chatbot @itbvp_bot is scalable. It allows working with several users at the same time, and its
intelligent system for choosing a web stack belongs to the class of distributed intelligent systems.</p>
      <p>Let's discuss some features of developing intelligent systems for chatbots and mobile applications
on the Android platform. The peculiarity of developing chatbots is that you can use either
TensorFlow, PyTorch, DialogFlow frameworks or develop an API. The work has chosen the path of
creating an API for a chat bot.</p>
      <p>The following features are available for intelligent mobile applications:


</p>
      <p>The first feature is that the asynchronicity of the Android operating environment determines
a multifactorial stratification of the knowledge base for the intelligent system
The second feature is the delay in presenting questions during a dialogue with the user when
using the FireMonkey framework
the third feature is the formation of a knowledge base for the Android platform, which must
be done separately from the Android platform itself. This must be done using frameworks
and shells</p>
      <p>The main programming languages for Android are Java and Kotlin. Since the KARKAS shell is
developed based on the cross-platform FireMonkey (FMX) framework from Embarcadero, chatbots
for Telegram and mobile applications for Android are developed using this framework.</p>
      <p>The main advantages of developing applications for the Android platform:



</p>
      <sec id="sec-6-1">
        <title>The Android platform is an open operating system Cross-platform Android It is easier to release an Android app on Google Play than in similar stores Intuitive user design from Google</title>
        <p>The disadvantage of developing applications for the Android platform is that testing the
application is more complex and takes more time.</p>
        <p>Given the cross-platform paradigm and the changing nature of mobile application development,
preference was given to the Android platform.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Conclusions</title>
      <p>The KARKAS shell is a toolkit for developing prototypes of knowledge bases for expert and
experttraining systems. Knowledge representation is based on a hierarchical functional system, which is
generated by the shell based on rules and frames. The inference engine uses the hierarchical
functional system during consultation with the user. The user can select different modes of operation
of the inference engine: using direct inference, reverse inference, indirect inference, Bayes formula.</p>
      <p>According to the brief overview of the works for chatbots and mobile applications, intelligent
systems mainly use the forward chain of reasoning for the inference engine. However, the forward
chain of reasoning leads to the user being asked unreasonable questions by the inference engine.
Therefore, a multi-factor knowledge base model is used for the API-based chatbot and Android-based
mobile applications. Factors are formed in the subject area to determine the subgoals of consultation
with the user. After questioning the user, the inference engine finds the meaning of the main goal
without user intervention.</p>
      <p>Firstly, the shell is designed for developing knowledge bases for Telegram chatbots and mobile
applications for the Android platform. In addition, it can be used to create prototypes of intelligent
systems [27].</p>
      <p>Secondly, integrated shell chatbots are monolithic applications. To use chatbots, they should be
hosted either on a virtual machine in the MS Azure cloud or on a computer with Internet access.</p>
      <p>Thirdly, the API-based intelligent system for the chatbot belongs to the class of distributed
intelligent systems, and the chatbot (@itbvp_bot) integrated with this system is scalable.</p>
      <p>Further research is aimed at developing an intelligent system model for integration with a chatbot
on the Facebook Messenger platform using API.</p>
    </sec>
    <sec id="sec-8">
      <title>Declaration on Generative AI</title>
      <sec id="sec-8-1">
        <title>The authors have not employed any Generative AI tools.</title>
      </sec>
    </sec>
    <sec id="sec-9">
      <title>References</title>
      <p>
        [4] R. Tiwari, G.M.S.S. Pranav, R. Prema, A research paper on human machine conversation using
chatbot, International Research Journal of Engineering and Technology (IRJET), 9(
        <xref ref-type="bibr" rid="ref3">3</xref>
        ), (2022)
1227–1233.
[5] P. Kostelník, I. Pisařovic, M. Muroň, F. Dařena, D. Procházka, Chatbots for enterprises: outlook,
      </p>
      <p>
        Acta universitatis agriculturae et silviculturae mendelianae brunensis, 67(6): (2019) 1541–1550.
[6] V. Burdaev, Features of Intelligent Systems Development for Platforms Telegram and Android,
in: Faure, E., et al. Information Technology for Education, Science, and Technics. ITEST 2024,
222 from Lecture Notes on Data Engineering and Communications Technologies, Springer,
Cham, 2024, pp. 156–171, doi:10.1007/978-3-031-71804-5_11.
[7] Delphi 10.4 Sydney Professional (Embarcadero), 2021. URL: https://www.embarcadero.com/en/
products/rad-studio.
[8] Android Mobile Application Development Homepage, 2022. URL: http://surl.li/omvru.
[9] M. Bagchi, Conceptualising a library chatbot using open source conversational artificial
intelligence, DESIDOC Journal of Library &amp; Information Technology, 40(6), 2020, pp. 329-333,
doi: 10.14429/djlit.40.6.156112020.
[10] M. Jang, Y. Jung, S. Kim, Investigating managers’ understanding of chatbots in the Korean
financial industry, Comput. Hum. Behav. 120 (2021), doi:10.1016/j.chb.2021.106747.
[11] O. Cherednichenko, D. Sytnikov, N. Romankiv, N. Sharonova, P. Sytnikova, Selection of Large
Language Model for development of Interactive Chat Bot for SaaS Solutions, in: Proceedings of
the 8th International Conference on Computational Linguistics and Intelligent Systems, Lviv,
Ukraine, 2024, pp.66–87.
[12] S. Fernandes, R. Gawas, P. Alvares, M. Fernandes, D. Kale, S. Aswale, Doctor Chatbot: heart
disease prediction system, Int. J. Inf. Technol. Electr. Eng., 9(5) (2020) 89–99.
[13] S. Sarinawati, G. J. Yanris, R. Muti’ah, Design and build expert system application for diagnosing
facial skin disease based on Android, Journal and Research of Informatics Engineering 7(
        <xref ref-type="bibr" rid="ref2">2</xref>
        )
(2022) 737–745.
[14] N. Akhsan, Development of Android-based expert system to diagnose faults on computer
devices, J. Intell. Decis. Support Syst. (IDSS) 3(
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) (2020) 13–18.
[15] S. Deshmukh, N. Umredkar, E. Sharma, R. Chalke,Smart doctor Android application for breast
cancer risk prediction and diagnosis. Int. J. Creat. Res. Thoughts 9(4) (2021) 5427–5432.
[16] P. Wangi, Al Munawir, S. Bukhori, The design of an Android-based lung disease screening
expert system and patient early warning using the forward chaining method at Waluyo Jati,
Kraksaan Hospital, Med. Technol. Public Health J., 6(
        <xref ref-type="bibr" rid="ref2">2</xref>
        ), 2022, pp. 157–168.
[17] D. Sava, M. Ca˘rbureanu, Android application for user’s real-time information regarding the
posibility of being contact to a covid-19 infected person, Rom. J. Pet. Gas Technol. 4(
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) (2023),
5–16.
[18] L. P. Wanti, N. W. A. Prasetya, O. Somantri, Expert system for diagnosing inflammatory bowel
disease using certainty factor and forward chaining methods, J. Innov. Inf. Technol. Appl. 5(
        <xref ref-type="bibr" rid="ref2">2</xref>
        )
(2023), 166–175.
[19] V. Burdaev, On one approach to building a temporal model of the knowledge base, in:
Proceedings of the 5th International Conference on Computational Linguistics and Intelligent
Systems, Lviv, 2021, pp. 1039–1048.
[20] V. Burdaev, Integration chat bota @RIBS_karkas_bot with expert system, in: V. C. Ponomarenko
(Ed.), Information Systems and Technologies, Kharkiv, 2019, pp. 37–51.
[21] Telegram Bot API, 2020. URL: https://core.telegram.org/bots/api.
[22] ES_IT, 2023. URL: http://surl.li/obgez.
[23] ES_RFCHD, 2023. URL: http://surl.li/omvoz.
[24] ES_DBT, 2023. URL: http://surl.li/sonhj.
[25] ES_MI, 2023. URL: http://surl.li/sonko.
[26] ES_HEPATITIS, 2023. URL: http://surl.li/sonkz.
[27] KARKAS, 2021. URL: https://en-it.karkas.com.ua.
      </p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>S.</given-names>
            <surname>Russell</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Norvig</surname>
          </string-name>
          , Artificial Intelligence:
          <string-name>
            <given-names>A Modern</given-names>
            <surname>Approach</surname>
          </string-name>
          , 4nd. ed.,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>J.</given-names>
            <surname>Giarratano</surname>
          </string-name>
          , G. Riley,
          <source>Expert Systems: Principles and Programming</source>
          , 4th ed. Thomson, Cambridge,
          <year>2007</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>K. L.</given-names>
            <surname>Ehsani</surname>
          </string-name>
          ,
          <string-name>
            <given-names>E. R.</given-names>
            <surname>Rhythm</surname>
          </string-name>
          ,
          <string-name>
            <given-names>H. K.</given-names>
            <surname>Mehedi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A. A.</given-names>
            <surname>Rase</surname>
          </string-name>
          ,
          <string-name>
            <surname>A Comparative</surname>
          </string-name>
          <article-title>Analysis of Customer Service Chatbots: Efficiency, Usability</article-title>
          and Application, Computer Applications &amp; Technological
          <string-name>
            <surname>Solutions</surname>
          </string-name>
          ,
          <year>2023</year>
          , doi:10.1109/CATS58046.
          <year>2023</year>
          .
          <volume>10424303</volume>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>