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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Data Exchange Platform for Digital Economy Applications</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Oleg Surnin</string-name>
          <email>surnin@o-code.ru</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anton Ivaschenko</string-name>
          <email>anton.ivashenko@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pavel Sitnikov</string-name>
          <email>sitnikov@o-code.ru</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anastasia Stolbova</string-name>
          <email>anastasiya.stolbova@bk.ru</email>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anastasia Khorina</string-name>
          <email>anastasiakhorina@mail.ru</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nataly Ilyasova</string-name>
          <email>ilyasova.nata@gmail.com</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Computer science department, Samara State Technical University</institution>
          ,
          <addr-line>Samara</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Data analysis department, IPSI SEC “Open Code”</institution>
          ,
          <addr-line>Samara</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Faculty of infocommunication, ITMO University</institution>
          ,
          <addr-line>Saint-Petersburg</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Image Processing Systems Institute of RAS, - Branch of the FSRC "Crystallography, and Photonics" RAS</institution>
          ,
          <addr-line>Samara</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>Information systems and technologies, department, Samara National Research University</institution>
          ,
          <addr-line>Samara</addr-line>
          ,
          <country country="RU">Russia</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2020</year>
      </pub-date>
      <fpage>243</fpage>
      <lpage>247</lpage>
      <abstract>
        <p>-This paper describes an experience of the Data exchange software platform practical use supporting the modern trends of Digital Economy. The platform was initially designed for the suppliers and customers of data sources providing the up-to-date technologies of big data processing as an online service. The platform is also open for software developers to upload new algorithms and technologies in order to help them to find new areas of application. There is presented architecture and its software implementation for an intermediary online platform capable of collecting, processing and analysis of various datasets. Modern companies being the members of digital economy can use this platform to process their data and produce business analytics. They can become both suppliers and providers of data, as well as develop and upload new customized algorithms. First results were achieved in the area of retail and social media analysis.</p>
      </abstract>
      <kwd-group>
        <kwd>data exchange</kwd>
        <kwd>digital economy</kwd>
        <kwd>big data</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>INTRODUCTION</p>
      <p>
        Data exchange platform is a new concept to organize an
efficient cooperation between the providers and customers of
various data sets and algorithms based on implementing the
software solution of open service provider [
        <xref ref-type="bibr" rid="ref1 ref2">1 – 2</xref>
        ].
Considering the results of open service software providers’
practical use [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], there was developed and probated new
software architecture capable of solving the actual problems
of business analytics in the different spheres of digital
economy.
      </p>
      <p>Such a solution is presented below with an illustration of
Data exchange platform application in network retail. Data
exchange platform implements the modern technologies of
big data analysis and capable of providing business analytics
and decision-making support in real time. The proposed
solution architecture and case study intended for processing
network retail data, predicting the processes, managing the
placement of big data, and planning the computing load
balancing.</p>
      <p>II.</p>
    </sec>
    <sec id="sec-2">
      <title>PROBLEM DOMAIN OVERVIEW</title>
      <p>Retail is a popular way to organize distributive trades.
Modern retail industry becomes a promising area of
development of network organizations that provide
distributed services for a large amount of consumers and
therefore processing the concerned flows of big data.</p>
      <p>The logic of this information processing is mainly
influenced by the processes of retail service. The following
areas of retail are distinguished:
street retail – organization of retail trade in the most
visited places: on pedestrian streets, ground floors of
buildings;
non-food retail – organization of trade in non-food
products, which in grocery stores, as a rule, are called
related. Such products include clothing, cosmetics,
household chemicals, stationery and other categories
of goods;
food retail – organization of food trade. This category
of goods is the most demanded and relates to
everyday goods;
network retail – organization with several stores of
the same chain united by one concept;
electronic retail – organization of trade through the
Internet;
cellular retail – organization of trade between mobile
operators.</p>
      <p>Retail industry gains significant benefits of being
adaptive to customer changing demands. Understanding the
trends and prediction of changes helps reducing costs and
increasing competitiveness. Application of modern
technologies for data collecting and processing can solve this
problem.</p>
      <p>Retailers use the following mechanisms to successfully
organize business processes that form the main requirements
for a data processing toolset:</p>
      <p>most optimal locations for
calculation of the
placement of outlets;
use of modern commercial equipment;
work with categories of clients;
work with methods of attraction;
development of self-service
personnel due to this;
optimization
suppliers;
automation of all stages of trade.
and
reduction
of
of logistics,
work
with
wholesale</p>
      <p>Depending on the specifics of retail problem domain and
other factors, a retail development strategy is determined.
The strategy operates with critical factors, by solving the
problems of determining the selling price of goods sold,
managing the assortment of outlets, and determining their
location.</p>
      <p>A comparison of the most frequently used business
intelligence systems in the retail sector for a number of the
most important criteria is shown in Table 1.</p>
      <p>Currently, electronic retail is popular and its popularity is
growing according to the main trends of digital economy
development. Electronic retail includes trade in both food
and non-food products, which leads to serious competition
among retailers. Price is the main factor that allows
companies to stand out among their competitors and attract
buyers, so pricing strategies should be the most flexible.</p>
      <p>There are a variety of approaches to pricing:



personalized approach to customers with the
formation of individual offers: this approach is based
on the analysis of the consumer behavior of each
specific buyer, the determination of his needs,
financial capabilities and, ultimately, the formation of
individual price offers for him;
promotion management: the approach is aimed at the
formation of special price offers for goods or groups
of goods according to certain criteria in order to
attract customers. In applying this approach, it is
important not to create a reputation as a discounter,
which can negatively affect the perception of the
retailer by customers, so promotions should be
temporary;
psychological techniques that affect the perception of
price. This approach is common for the retail industry
as a whole and is quite popular, due to the ease and

low cost of its application. For example, to sell an
expensive product, you need to put it next to an even
more expensive product. Another fact that has been
studied is that the customer has a high probability that
he or she will not have a single price, so a small
difference in price should be left for similar products.
Psychological techniques include managing delivery
prices. It is very often necessary to arrange delivery.
Modern research shows that most shoppers leave the
store basket. The offer of free delivery or promotional
goods when making delivery positively affects the
customer;
predictive pricing is a fairly effective approach, the
main task of which is to determine how price affects
demand. The approach allows you to model changes
in demand depending on the price, taking into
account various factors, including other methods
involved in pricing: psychological pricing, the
influence of competitors, behavioral models and
categories of current retailer customers, current trends
(in the fashion industry or global trends in lifestyle
changes).</p>
      <p>III.</p>
    </sec>
    <sec id="sec-3">
      <title>STATE OF THE ART</title>
      <p>
        The results of [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] show that retailers are moving to more
innovative strategies to offer modern consumer solutions
based on technological advances. The high level of property
rights, due to the enormous number of patents, forces
retailers to invest more in the acquisition of patented
technologies to achieve advantages over competitors or to
introduce new management methods.
      </p>
      <p>
        The need to analyze retail data in a highly competitive
environment is shown in [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Advances in machine learning
and big data lead to the use of data analytics management
systems in many organizations and industries.
      </p>
      <p>As a rule, large organizations can devote more resources
to this, and the software used is more suitable for large
enterprises. However, the growing business pressure is
forcing small and medium-sized enterprises to implement
data analytics, which is new to them and leads to a number of
problems considered in [5].</p>
      <p>
        Social networks have become a part of life for most
people around the world. Retailers (and not only) are actively
using them to share information about their products with
customers. As a result of the growth of social networks, the
need for monitoring, data mining and analysis is increasing.
So, in determining the tasks and opportunities of network
retail, the issues of integration with social networks,
determining a development strategy and studying the life
cycle of clients are relevant [
        <xref ref-type="bibr" rid="ref6 ref7">6, 7</xref>
        ]. The study of customer
behavior models requires taking into account completely
diverse data and improving their analysis.
      </p>
      <p>
        In [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], the questions of creating a body of knowledge are
considered, the concept and key methods of data analysis are
studied in the field of retail network, the creation of data
exchange methods [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], such as shopping basket analysis [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]
and sales analysis in general using business intelligence
tools.
      </p>
      <p>
        Analysis of factors of customer satisfaction and loyalty,
the image of retailers and the relationships between them
lead to the emergence of models for creating a satisfactory
experience for consumers, which is a priority for retailers
[
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. The influence of fluctuations in demand and purchasing
power on macroeconomic regulation and state control are
considered in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
      </p>
      <p>
        Research on the effects of loyalty programs on the
decision to purchase goods at different periods of time is
relevant, since an important factor for multichannel grocery
retailers is which promotion strategy to choose across all
channels. The tendency of product buyers to continue to visit
an offline store after they start buying in the online store of
the network means that promotions in one channel can have
a significant negative impact on the behavior of customers in
another channel, especially if promotions differ by channel
[
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>To solve the above mentioned problems of network retail
there can be used a variety of data sources. For example, it is
possible to analyze data obtained in the following areas:
1. Acquiring data which includes information about the
commission of the acquiring bank, categories of outlets,
payment card options, which allows you to determine the
dependence of the availability of sales outlets on the
availability of POS terminals;
2. Retailer data, which include:
 information on loyalty programs and promotions to
determine the dependence of demand on the
availability of various special offers for goods;
 information about regular customers and users of
loyalty programs to analyze the dependence of the
purchased goods on the categories of customers, to
form the most advantageous offers for both the buyer
and the retailer. In addition, it is possible to evaluate
the customers in terms of how much money they
spend and how often they make purchases in retailers’
stores, which will determine the significance of each
customer for the network and more accurately
formulate personal offers;
 date of purchase and time of purchase to analyze the
dynamics of demand for certain products depending
on seasonality and time of day. In addition, it is
necessary to take into account various holidays and
ongoing events in the analyzed region;
 the list of goods on the check allows you to analyze
the most frequently purchased goods together;
 the price of the items listed in the check and the total
purchase amount allow the analysis of the turnover of
the outlet;
 the trajectory of buyers allows you to determine the
order of purchases at retail outlets and to identify the
optimal location of goods in the store;
3. Social media that help identification of fashion trends
and identify the dependence of purchases as well as the most
popular brands and products;</p>
      <p>4. Geo data that can be used to determine the dependence
of consumer activity, demand for goods, payment methods
depending on the territorial location of the outlet and the
nearby infrastructure, such as the area (sleeping, tourist,
business centers and others), categories of users visiting or
living in the area.</p>
      <p>According to the commission of the Code of good
practices, it is known that retailers do not want to share sales
data of individual outlets with suppliers, which leads to an
inaccurate assessment of their activities, loss of productivity,
and, consequently, loss of income.</p>
      <p>IV.</p>
    </sec>
    <sec id="sec-4">
      <title>SOLUTION ARCHITECTURE</title>
      <p>Having considered the tasks and problems of network
retail, strategies for solving them, we can conclude that the
creation of a data exchange platform is a necessary step for
the business development, and its intellectualization is an
integral part of the process.</p>
      <p>Intellectualization includes the introduction of the
following technologies into the data exchange:</p>
      <p>1. Face recognition. Biometric assessment systems can
optimize salary costs, allow you to calculate the costs of
nonstaff employees and minimize the risks of dishonest actions
and counteractions. The introduction of face recognition can
also significantly increase understanding of the
characteristics of the average buyer. Indeed, many algorithms
allow you to evaluate gender, age, race, and thereby form a
portrait of the buyer. To solve such problems, a camera is
used, aimed close-up at incoming visitors, with a face
detection function. Additionally, such algorithms in
combination with the display of advertising can give an
understanding of the effectiveness of advertising on visitors.</p>
      <p>2. Creating smart baskets. Built-in cameras that can
recognize and scan products, sensors that detect the detection
of an object in the basket, as well as scales that allow you to
get rid of additional weighing of fruits and vegetables. On
the trolley screen, the buyer will be able to see all the
products taken, as well as their total amount. The data that
carts collect (on routes through stores, on the frequency of
purchases of goods from certain shelves, where customers
are, etc.) would help company partners optimize their stores.</p>
      <p>3. Analysis of social networks. Analysis of data from
social networks will allow you to analyze customer
complaints in real time and track user requests and wishes.
Location and shopping data will allow you to compile the
most complete portrait of a specific retailer buyer.</p>
      <p>4. Internet of things. When it comes to retail, the IoT
infrastructure includes RFID tags, infrared traffic meters in
stores, satellite and Wi-Fi tracking systems, digital
signatures, kiosks or even mobile devices of the customers
themselves. The Internet of things makes it possible to
implement predictive maintenance of equipment,
transportation, keeping a warehouse on the basis of demand,
tracking the activity of buyers, creating a smart store,
behavioral analytics, personalized marketing and real-time
advertising based on location and purchase history.</p>
      <p>5. Adaptive Acquiring. The sources of such a data
exchange are intelligent systems. Data processing can give
conflicting results in different contexts and in the absence of
data, but the results obtained should provide decision-making
support. Technologies without data will not give the desired
result, as well as data without applying the necessary
technologies to them. So, the data exchange can be presented
as a platform for interfacing digital intelligent services.</p>
      <p>The proposed software solution for a data exchange
platform is presented in Fig. 1. It was implemented using
Java (IntelliJ IDEA 15.0.3 Integrated Software Development
Environment (Community Edition)) and supports JavaScript,
CoffeeScript, HTML / XHTML / XAML, CSS / SASS /
LESS, XML / XSL / XPath, YAML, ActionScript / MXML,
Python, Ruby, Haxe, Groovy, Scala, SQL, PHP, Kotlin,
Clojure, C, C ++.</p>
      <p>In the considered example, users were searched for the
following product groups: 3 (energy granola bars), 4 (instant
foods), 5 (marinades meat preparation). As can be seen from
Figure 2, for the buyer with the number 141848112, you can
create an offer for goods from group 3 (energy granola bars),
and for the buyer with the number 78310286 – 4 (instant
foods).</p>
      <p>Additional libraries and frameworks include Apache
Hadoop, Apache Spark, and Django. Apache Hadoop
(HDFS) is a file system designed to store large files,
blockby-block distributed between nodes of a computing cluster.
Apache Spark is an open source framework for
implementing distributed processing of unstructured and
weakly structured data, which is part of the Hadoop project
ecosystem.</p>
      <p>The developed data exchange platform provides the
functionality for pre-processing and analysis of network
retail data. As a part of data pre-processing the system
implements the methods of data structuring, omission
processing, and data dimension reduction, trend highlighting,
and correlation analysis.</p>
      <p>To solve the problems of network retail analysis, there is
a possibility to use the following:



</p>
      <p>Apriori, FPG (Frequent-Pattern Tree) methods help
solving the problem of analysing a shopping cart;
Linear regression methods are used to solve the
forecasting problem;
The Mean method is used to calculate average values;
K_means method is used for various kinds of
clustering.</p>
      <p>Besides, a wide range of methods such as ARIMA, FB
Prophet and others are used to analyse time series.</p>
      <p>The following example illustrates the results of Data
exchange platform development. We create a project for
personal offers on selected categories of goods formed by a
retailer for users of a social network with loyalty cards.
Forming this request is useful if you need to increase sales
for certain categories of goods available to the retailer.</p>
      <p>The result of this query is a list of users who are
interested in purchasing goods for selected groups of goods
with an indication of the group. By analyzing the results
obtained, the retailer can formulate personal offers for the
groups of goods chosen by him for the most suitable
customers.</p>
      <p>Another popular task in the field of network retail
analysis is the sales forecast. The following fields were
selected as the initial data of the problem to be solved: store
identifier, purchase date, purchase amount.</p>
      <p>To solve the problem, there were combined the basic
methods powered by the developed data exchange platform:




python_basic_filter – the method allows you to
select sales data for one store from many;
python_basic_resample – the method allows you to
aggregate data by day, summing them up;
python_timeseries_holt_winters – the method allows
forecasting using the Holt-Winters additive model
(triple exponential smoothing).</p>
      <p>python_plotly_forecast – a method for plotting.</p>
      <p>The ability to combine methods makes it possible to
choose the most suitable analysis algorithm, taking into
account the specifics of the source data. The project drawn
up in the query designer is shown in Fig. 3.</p>
      <p>The result of this project is the forecasted revenue values
of the selected store, taking into account the seasonality
period with a sales horizon.</p>
      <p>The proposed approach opens new perspectives for
online services providers and buyers cooperation in common
information space. According to the current trends of
economy digital transformation most services migrate to web
platforms transporting all negotiations between the business
parties to virtual reality.</p>
      <p>Therefore social media become a substantial part of
business relations. The resulting effect forms the economy of
ultra-low expenditures. On the one hand, the members on
such relations can swiftly change their mind by getting better
options, producing the contract agreements that are easy to
enter and easy to leave. On the other hand, all the games are
being fixed, and the members agree to play open.</p>
      <p>Under these conditions a new class of intermediary open
service platforms starts playing the general role. Using the
existing IT infrastructure they allow building a new virtual
world powered by business analytics. In this sphere
decisionmaking can no longer be done by humans themselves. All
the decisions need a support from data analysis and machine
learning, which makes the access to them even more
important than economy resources available in real life.</p>
      <p>VI.</p>
      <p>CONCLUSION</p>
      <p>The developed solution based on the data exchange
platform allows predicting the processes of network retail
manage the placement of big data and plan the computing
load based on the info logical model, which will increase the
sales efficiency.</p>
      <p>Next steps are related to extending the area of
intermediary open service application including the problem
domains of social analysis and services automation. Positive
results were also achieved in banking acquiring, which can
be extended in business sphere making the data processing
an effective tool of economy digital transformation.</p>
      <p>Main research results include the following deliverables:
big data management methodology (O. Surnin), and its
implementation by Open code platform architecture (P.
Sitnikov), analysis of its perspective for digital economy (A.
Ivaschenko) based on implementation of data exchange
model (A. Stolbova) and algorithms of semantic (A.
Khorina) and statistics (N. Ilyasova) analysis.</p>
    </sec>
    <sec id="sec-5">
      <title>ACKNOWLEDGMENT</title>
      <p>This work was financially supported by the Russian
Foundation for Basic Research under grant # 19-29-01135
and by the Ministry of Science and Higher Education within
the State assignment to the FSRC “Crystallography and
Photonics” RAS.</p>
    </sec>
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