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- International Journal of Management (IJM)
Volume 11, Issue 5, May 2020, pp. 54-64, Article ID: IJM_11_05_006
Available online at http://www.iaeme.com/ijm/issues.asp?JType=IJM&VType=11&IType=5
Journal Impact Factor (2020): 10.1471 (Calculated by GISI) www.jifactor.com
ISSN Print: 0976-6502 and ISSN Online: 0976-6510
DOI: 10.34218/IJM.11.5.2020.006
© IAEME Publication Scopus Indexed
OPTIMIZATION MODEL OF THE ENTERPRISE
LOGISTICS SYSTEM USING INFORMATION
TECHNOLOGIES
Mariya Naumenko
Department of Management and Military Economy,
National Academy of the National Guard of Ukraine, Kharkiv, Ukraine
Nataliia Valiavska
Department of Business Logistics and Transportation Technology,
State University of Infrastructure and Technologies, Kyiv, Ukraine
Mariia Saiensus
Department of Marketing, Odessa National Economics University, Odessa, Ukraine
Olena Ptashchenko
Department of International Business and Economic Analysis,
Simon Kuznets Kharkiv National University of Economics, Kharkiv, Ukraine
Vitalii Nikitiuk
Department of Economics, Kremenchuk Mykhailo Ostrohradskiy
National University, Kremenchuk, Ukraine
Anton Saliuk
Department of Marketing and Corporate Communications Department, Simon Kuznets
Kharkiv National University of Economics, Kharkiv, Ukraine
ABSTRACT
The proposed model for optimizing the logistics system of an enterprise using
information technology. The motivation to build the model emphasizes the critical role
that new information technologies play in significantly increasing the availability of
data of a wide variety of types related to the transportation process and servicing
logistics tasks. In particular, the ability to operate in real-time with a significant
amount of detailed data collected locally can potentially improve the accuracy of
information about critical unobserved characteristics of the production process.
Among such unobservable values, one can indicate various kinds of attributes of the
efforts made by the organization and individual employees to achieve different goals
and objectives of providing logistics services.
http://www.iaeme.com/IJM/index.asp 54 editor@iaeme.com
- Optimization Model of the Enterprise Logistics System Using Information Technologies
Keywords: Enterprise, Information Technologies, Logistics System Optimization
Model
Cite this Article: Mariya Naumenko, Nataliia Valiavska, Mariia Saiensus,
Olena Ptashchenko, Vitalii Nikitiuk, Anton Saliuk, Optimization Model of the
Enterprise Logistics System Using Information Technologies, International Journal of
Management, 11 (5), 2020, pp. 54-64.
http://www.iaeme.com/IJM/issues.asp?JType=IJM&VType=11&IType=5
1. INTRODUCTION
Information technology in logistics has two useful functions.
Firstly, with their help, the process of receiving orders, processing goods, selecting,
sending and invoicing is accelerated. The faster all this happens, the shorter the order cycle
from the point of view of the buyer, less paperwork and errors, and hence cost. If the
company can quickly respond to customer requests, it reduces the uncertainty for itself
regarding fluctuations in demand and the timing of orders. It thus eliminates the need for extra
insurance stocks.
Secondly, information technology has a good effect on the planning and evaluation of
alternatives. To do this, you can use decision support tools that can increase the speed,
accuracy and completeness of logistic decisions. The level of determining the location of each
unit of production at the moment predetermined the need for processing huge volumes of
data. Modern information technology allows you to implement such processing. In particular,
information technology provides an opportunity to compare the quality of services of various
suppliers, assess the effectiveness of product distribution [1-5].
The use of information technology in the logistics systems of Ukrainian enterprises is
continually growing (Fig. 1)
250 180.0%
159.1% 160.0%
204.5
200
140.0%
123.6% 131.6%
125.6% 111.2%
116.7% 155.4 120.0%
114.9%
111.5% 112.4% 111.6% 111.4%
150 139.5
101.3% 100.0%
94.6%
90.6% 112.9
101.5 80.0%
100
69.5 60.0%
62.3 63 63.8
49.6
40.0%
50 37.8 42.5
31.2 29.5 32.9
20.0%
0 0.0%
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
million UAH Growth rate, %
Figure 1 The use of information technology in the logistics systems
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- Mariya Naumenko, Nataliia Valiavska, Mariia Saiensus, Olena Ptashchenko,
Vitalii Nikitiuk, Anton Saliuk
Finally, it comes to the understanding that processing information flows is no less
necessary than real ones. It should be noted that the evolution of the world market gives
advantages to a country that creates high-tech products, including new technologies and
modern professional knowledge, for producing and transferring for production to other
countries.
2. ENTERPRISE LOGISTICS SYSTEM
Logistics is the science and art of planning, organizing, creating the conditions for motivation
and controlling the progress of the material flow.
One of the options for the logistics system, demonstrating its concept or principles, is
shown in Fig. 2.
Materials Management Distribution Management
(Supply) (Sales)
Stocks Intermediate
link
Finished
Raw materials, products
spare parts, (enterprise
semi-finished Unfinished warehouse)
products, Consumer
production or
packaging
end user
Finished
products
Intermediate
link
Production
Logistics
Figure 2 Logistics Information System Functions
The principle of the logistics system, or its concept, is associated with the management of
materials (with supply) and with the management of distribution (with sales). American
scientists believe that logistics provides a mechanism for developing tasks and strategies
within which daily material flow management activities can be carried out. One of the
features of the logistics principle is that not only special attention is paid to the integration of
activities, but also their integration is carried out. For example, in many companies,
responsibility for inventories and responsibility for transportation can be considered
production and distribution functions, respectively, and decisions on the former are often
made without regard to the latter. In the logistics system, both of them must be
interconnected, and the negative and positive aspects of the various functional areas of the
logistics system must be taken into account.
When creating a logistics system, as a rule, these functional areas of logistics are used.
Therefore, the main costs of logistics are the sum of the costs of transporting the product, its
storage, maintaining inventory, receiving, shipping and packaging of goods; order processing
costs; administrative expenses, etc.
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- Optimization Model of the Enterprise Logistics System Using Information Technologies
Data on shares of the total logistics costs of each of its functional areas is presented in Fig. 3.
18
Transport
10 46 Warehousing
Stocks
Other
26
Figure 3 The share of the total cost of logistics of each of its functional areas
The logistics system is not only a source of costs but also a potential tool for creating
demand for products. By improving the logistics system, you can offer the best service or
lower prices, thereby attracting additional customers. The company loses customers when it
does not ensure the delivery of goods on time. Hence, customers claim that the possibility of
organizing a quick supply is valued by them more than the popularity of the trademark of the
supplier company.
3. INFORMATION TECHNOLOGY IN LOGISTICS
For the implementation of precise control in the material through the stream, specific
procedures must be performed, as well as the availability of appropriate means and methods
of information processing. Automated information systems at the macroeconomic agent level
are divided into the following groups:
1) planned;
2) dispatching;
3) operational.
Planned information systems are intended for management at the administrative level; their
competence includes the adoption of long-term strategic decisions; planning is carried out in
the chain of material flow "sales-production-supply". This group is in charge of such tasks as:
1) optimization and creation of new and existing links in the material flow;
2) management of conditionally constant data that changes little during organizational work;
3) planning of production stages;
4) the general supervision of the resources and reserves of the organization;
5) reserve management;
6) demand and resource planning.
Dispatching information systems are intended for management at the warehouse and
workshop levels; they are stabilizers of the operation of logical information systems. They can
work in various ways: in batch mode or through interactive processing.
The competence of dispatching information systems includes:
1) disposal of intra-organization transport (in-plant or in-warehouse);
2) inventory management of manufactured products (places of storage, warehousing);
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- Mariya Naumenko, Nataliia Valiavska, Mariia Saiensus, Olena Ptashchenko,
Vitalii Nikitiuk, Anton Saliuk
3) contract supplies and provision of materials and resources;
4) the formation of goods on orders, their picking and accounting.
Operational information systems are intended for management at the administrative and
operational level. This system is characterized by a high speed of processing relevant
information, which arrives at high speed to the computer, which makes it work on-line. This
system implements the following features:
1) information on the movement of goods at the current time;
2) the issuance of administrative and control actions on the control object;
3) warehouse management and inventory accounting;
4) preparation for sending products;
5) operational production management;
6) management of automated equipment.
The following hierarchy of information systems can be distinguished in the logistics
management of an enterprise.
The functions of the logistic information system (Fig. 4) [6-10].
Planning function
• forecasting;
• inventory management.
Databases: Communication
Coordination • external data; function of
function
• internal data. customer service
Control function
• key indicators.
Figure 4 Logistics Information System Functions
Databases:
• external data: customer requests and consignments coming from abroad;
• internal data: production and stocks.
Planning function:
• inventory management: taking into account the goods/buyer, taking into account the
location;
• demand forecasting;
• strategic planning.
Coordination function:
• scheduling production;
• material requirements planning;
• sales/marketing planning.
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- Optimization Model of the Enterprise Logistics System Using Information Technologies
Communication function of customer service:
• status of the customer’s order;
• availability of stocks: taking into account the assortment of goods + taking into
account the location of goods;
• the condition of goods arriving from abroad.
Control function:
• customer service level;
• the effectiveness of the seller;
• carrier performance;
• the effectiveness of the system as a whole.
4. METHODOLOGY FOR THE IMPLEMENTATION OF
INFORMATION TECHNOLOGY TO OPTIMIZE THE LOGISTICS
SYSTEM OF THE ENTERPRISE
The introduction of information technology creates additional opportunities for optimizing the
logistics system of the enterprise. The fast transfer of large amounts of data and the rather
complicated processing of this data in tight time intervals contribute to the introduction of
more complex methods of organizing transport management, which allows increasing the
economic efficiency of the enterprise, which ultimately affects the growth of its profitability.
In particular, the introduction of information technology makes it easier to collect data and
improves the quality of information collected about production and logistics processes.
Correctly interpreted information of this kind (processed by appropriate algorithms) allows
earlier to identify problems in the process of organizing logistics, to find bottlenecks and,
thereby, contribute to the earlier adoption of measures to eliminate them.
Ensuring the proper set and level of efforts and measures for the implementation of
technological operations can be controlled with greater accuracy using modern information
technologies. Consider the enterprise logistics process from the point of view close to the
classical economic production function (1):
𝑦 = 𝑓(𝑒) + 𝜀 (1)
where y is the level of transportation services (expressed in appropriate units, for example,
ton-kilometers), e is the level of efforts to carry out the corresponding technological
operations, f is the production function responsible for the cause-effect relationship between
the efforts expended and the size of the services performed, and, finally, ε is a random
component describing the influence on the logistic process of factors whose accounting is
either impossible or too costly for the optimal organization of the transport process.
A possible general form of the functional dependence of the level of services on the level
of expended efforts is presented in Fig. 5.
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- Mariya Naumenko, Nataliia Valiavska, Mariia Saiensus, Olena Ptashchenko,
Vitalii Nikitiuk, Anton Saliuk
y
f(e)
A0e + B0
e
Figure 5 The functional form of the dependence of the level of logistics services on the effort
Among the usual characteristics of such a dependence, one should mention an increase in
the function f (the level of logistics services grows with an increase in efforts to provide
them). At the same time, the growth may slow down with an increase in efforts (the function f
is concave in a non-strict sense). Presumably, the influence of random factors, regardless of
the effort expended, is distributed around zero, more precisely, 0 is the median of the
distribution (2):
𝑃(𝜀 < 0) = 𝑃(𝜀 > 0) (2)
The situation should be considered natural when, at the level of management of the
logistic process, it is not possible to observe the level of efforts e directly, but only the final
level of services y. In this case, it is possible to implicitly calculate the "expected" level of
effort, based on the observed level of services provided (3):
𝑒 ∗ = 𝑀(𝑓 −1 (𝑦 − 𝜀)|𝑦) (3)
where M is the median of the conditional distribution. Moreover, not knowing the specific
form of the distribution of the random factor 𝜀, the organizer of the logistic process can only
evaluate the right side of the above formula. For example, in the case of a number n of
independent results of the logistic process with presumably the same level of effort, an
empirical median can be used (4):
1
𝑒̂ ∗ = ̂ + 𝑚𝑖𝑛𝑀
(𝑠𝑢𝑝𝑀 ̂) (4)
2
where 𝑀 ̂ is the operator of the power of the set.
In the case of a more special type of the production function of the logistic process 𝑓(𝑒) =
𝐴0 𝑒 + 𝐵0 (see Fig. 3) and the additional requirement 𝐸(𝜀) = 0, the effort spent can be
estimated using the empirical mean (5):
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- Optimization Model of the Enterprise Logistics System Using Information Technologies
1
∑𝑛𝑖=1 𝑦𝑖 − 𝐵0
∗ 𝑛
𝑒̂ = ( ) (5)
𝐴0
Note that the variance of the error of this kind of estimate will be 𝜎 2 /𝑛 if the variance of
the random factor was 𝜎 2 . Of course, in reality, there are few opportunities to observe the
results of independent logistics processes with the same level of effort. In this case, the
variance of the error obtained above the estimate will not significantly differ from the
variance of the random factor of the logistic process (and in the case of one observation, 𝑛 =
1 will coincide exactly with it).
How can the implementation of information technologies help in this case? Presumably,
information technology will allow you to receive, save and process other signals that carry
relevant information about the effort spent. In other words, the introduction of information
technologies in this model can mean the addition of additional observable values (more
detailed data on how the logistics process proceeds) of the form (6):
𝑧𝑗 = 𝐵𝑗 + 𝐴𝑗 𝑒 + 𝜀𝑗 , (𝑗 = 1, … , 𝑘) (6)
where random factors 𝜀𝑗 can be considered independently distributed with an average
(mathematical expectation) of 0.
Adding additional data of this kind, generally speaking, can significantly improve the
initial assessment of the effort spent, even having only one "observation" (one realized case of
the organization of the transport process). Indeed, in most cases, the following estimate will
be better than the initial one (7):
𝑛 1 𝑘 1
( ∑𝑛𝑖=1 𝑦𝑖 − 𝐵0 ) ( ∑𝑘𝑗=1 𝑧𝑗 − 𝐵𝑗 )
𝑒̂ ∗ = 𝑛+𝑘 𝑛
+ 𝑛+𝑘 𝑛 (7)
𝐴0 𝐴𝑗
In this case, the variance of the error of this estimate will be equal to (8):
𝑘
𝑘
(𝑛𝜎 2 + ∑ 𝜎𝑗2 ) (8)
(𝑛 + 𝑘)2
𝑗=1
where 𝜎𝑗2 is the variance of the random factor 𝜀𝑗 . In other words, the new estimate will be
better than the old one if the average variance of random data factors available using
information technology does not exceed (2𝑛 + 𝑘)𝜎 2 – which is significantly higher than the
variance of the original random factor. Also, with an increase in the quantity and quality of
data being collected within the framework of implemented information systems (an increase
in k and a decrease in the average variance 𝜎𝑗2 ), the accuracy of estimating the expended
efforts 𝑒̂ ∗ also increases.
In other words, with sufficient accuracy of the data obtained using information technology
(and the accuracy restrictions are quite onerous), accounting for these data can significantly
optimize the enterprise’s logistics system, allowing it to better control the nature of the
enterprise’s internal logistics processes in the presence of numerous random factors.
http://www.iaeme.com/IJM/index.asp 61 editor@iaeme.com
- Mariya Naumenko, Nataliia Valiavska, Mariia Saiensus, Olena Ptashchenko,
Vitalii Nikitiuk, Anton Saliuk
5. RESULTS AND DISCUSSION
As an example, we consider the situation with one type of data, the ability to take into account
which could arise as a result of the application of information technologies to optimize the
logistics system of the enterprise. Suppose that as such a type of data, it became possible to
take into account the percentage of goods detained in individual sections of the supply chain
for more than a certain period concerning the planned one. This value will be denoted by z1.
At the same time, the target variable y, the influence of which efforts on the part of the
company's employees needs to be monitored, will take the percentage of goods delivered by
this territorial division of the company on time. Of course, the focused efforts of the
enterprise's employees to ensure timely delivery of goods and denoted by us as e will affect
both the variable of interest y and additional data z1. As a linear approximation in the field of
currently achieved levels of efficiency, we can assume that the nature of these types of
influence is described in the form of equations (9) – (10):
𝑦 = 𝐵0 + 𝐴0 𝑒 + 𝜀0 (9)
𝑧1 = 𝐵1 + 𝑒 + 𝜀1 (10)
Under the "efforts of employees" is understood, for example, the number of working
hours spent by employees to ensure the timely delivery of goods, provided that the quality of
the work carried out by employees corresponds to a given reference level. At the same time,
the choice of the scale is quite arbitrary, so we can normalize it so that in the equation for the
connection with the percentage of delays in certain parts of the chain, our magnitude of effort
is included with a coefficient of 1.
In addition to the scale, we are also free to choose the starting point of reference and to
consider under the efforts not the absolute value of the hours spent by the employees, but their
deviation from some predetermined standard. The reference can be chosen in such a way that,
when choosing a reference level of effort (which in our designations will correspond to e =
0), the expected percentage of product delays in individual sections of the logistics chain will
be equal to a predetermined value, which, as is easy to see, will be unambiguous identify the
coefficient B1, because for 𝑒 = 0 we get 𝐸𝑧1 = 𝐵1. As the expected percentage of product
delays in individual sections of the supply chain, we take the value 𝐵1 = 10.
Once we have decided on the normalization of the level of effort, it remains for us to
determine the remaining coefficients 𝐵0 and 𝐴0 . To determine them, we substitute the
expression for e from equation (9) into equation (10). We get:
𝑦 = 𝐵0 − 𝐴0 𝐵1 + 𝐴0 𝑧1 + 𝜀̃ (11)
where 𝜀̃ = 𝜀0 − 𝐴0 𝜀1. Thus, we expressed the observed value of y in terms of the observed
(due to information technology) value of 𝑧1 and random error 𝜀̃. In other words, we can find
an estimate of the coefficients 𝐵0 and 𝐴0 , using the usual linear regression of y on 𝑧1 , we
obtain:
1 ∑𝑛 𝑛
𝑖=1 𝑦𝑖 ∑𝑖=1 𝑧1𝑖
∑𝑛𝑖=1 𝑦𝑖 𝑧1𝑖 −
𝑛 𝑛
𝐴0 = ∑𝑛 2 (12)
𝑧
∑𝑛𝑖=1 𝑧1𝑖
2
− 𝑛 𝑖=1 1𝑖
𝑛 𝑛
∑𝑖=1 𝑦𝑖 ∑𝑖=1 𝑧1𝑖
𝐵̂0 = − 𝐴̂0 + 𝐴̂0 𝐵1 (13)
𝑛 𝑛
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- Optimization Model of the Enterprise Logistics System Using Information Technologies
Table 1 shows the possible observed values of y and z1 in 12 cases.
Table 1 Observed percentages of goods delivered on time and percent delays in individual sections of
the logistics chain
S. No Goods delivered on time, % Delays, %
1 8,72 12,98
2 9,12 12,83
3 6,77 4,63
4 4,95 5,51
5 7,17 14,39
6 7,69 8,15
7 14,2 9,22
8 9,1 12,5
9 5,69 7,5
10 0,72 8,04
11 10,4 8,6
12 4,2 6,8
Using these data, by virtue of formulas (12) and (13) we obtain:
𝐴0 = 0,44; 𝐵0 = 9,01
Suppose now that after obtaining the estimates of the coefficients in equations (9) and
(10), which describe the dependence of our observed data on the expended unobserved
efforts, the manager observes the current (one) implementation - the result of work over the
past month in terms of ensuring the delivery of goods on time y and the share of delayed
goods in certain sections of the logistics chain z1. Based on these data, the manager can make
the following assessments of unobserved staff efforts:
𝑒̂ ∗ = (𝑦 − 9,01)/0,88 + (𝑧1 − 12) / 2
The accuracy of this formula is given by the reciprocal of the variance:
1
1 = 0.5
(𝜎 2 + 𝜎12 )
4
At the same time, the accuracy of the formula, which does not take into account the
information contained in the information collected by the information system, of the percent
of goods detained in individual sections of the logistics chain is 1/𝜎 2 = 25 (the estimate
itself is given 𝑒̂ ∗ = (𝑦 − 9,01)/0,44), which is 1.85 times less than the above value.
6. CONCLUSION
Logistics can rightfully be considered a significant factor in the implementation of measures
aimed at improving the economic efficiency of production and marketing. Substantial
progress in rationalizing these areas of activity can be achieved by maximizing the
coordination of material and information flows when they are combined, which is one of the
main tasks of logistics. To solve it, the widespread use of electronic data processing,
standardization of material and technical relations, organization of work based on scientific
functional analysis and structuring, as well as the use of new technologies leading to
automation of operations are required.
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- Mariya Naumenko, Nataliia Valiavska, Mariia Saiensus, Olena Ptashchenko,
Vitalii Nikitiuk, Anton Saliuk
The use of information technology in logistics systems is aimed at ensuring the
distribution of goods and interaction between departments of the enterprise, as well as
between enterprises in the process of supply and marketing of goods.
A further area of research may consider the construction of integrated computerized
information systems, which require appropriate technical, software and linguistic support.
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