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Abstract

In the contemporary world, natural gas is one of the focuses of hybrid wars and is used as a tool of international economic and political pressure to gain appropriate benefits. The long-term pressure of Russia on Ukraine using a combination of military, political, economic, information and energy tools is one of the most striking cases of applying natural gas as a weapon in a hybrid war. Exploring the case of Ukraine, the authors confirmed the hypothesis about the change in the impact of the prices of natural gas on the performance of its industrial consumers during a hybrid war. The study covered three industrial sectors that are major consumers of natural gas – the metallurgy, chemical and pharmaceutical industries. The data of nine key companies of these industries for the period 2006–2019 were analyzed; this period was divided into two parts – before the hybrid war (2006–2013) and during it (2014–2019). The authors identified the heterogeneity of the influence of natural gas prices on the performance of different industrial enterprises. However, since the onset of the hybrid war, all of them have shown a reducing correlation of natural gas prices with all the analyzed performance indicators – operating profitability, material-output ratio, and labor productivity. The study managed to build reliable regression models that allow defining the prices of natural gas for the chemical industry and metallurgy, above which these industries in Ukraine become unprofitable. The defined critical levels have a practical implication since they can be tools for regulating natural gas prices for various industrial sectors.
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Authors and Affiliations

Anatoliy G. Goncharuk
1
ORCID: ORCID
Valeria Liashenko-Shcherbakova
1
ORCID: ORCID
Natalia Chaika
1
ORCID: ORCID

  1. Department of Management, International Humanitarian University, Ukraine
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Abstract

The article presents research on the relationship between mining and used resources on the example of Gliśno gravel pit. As regards to resources, the following issues were analyzed: employees’ working time, time of running machines, fuel consumption and electricity consumption. The aim of the publication is to examine the dependencies that exist between the analyzed variables. KPI’s (Key Performance Indicators) were calculated for individual resources. The analysis presented in the publication contains data from 2008-2014.

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Authors and Affiliations

Marcin Olkiewicz
Radosław Wolniak
Bartosz Ostapko
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Abstract

Outdoor lighting is an important element in creating an evening and nocturnal image of urban spaces. Properly designed and constructed lighting installations provide residents with comfort and security. One way to improve the energy efficiency of road lighting installation is to replace the electromagnetic control gear (ECG) with electronic ballasts (EB). The main purpose of this article is to provide an in-depth comparative analysis of the energy efficiency and performance of HPS lamps with ECG and EB. It will compare their performance under sinusoidal and nonsinusoidal voltage supply conditions for the four most commonly used HPS lamps of 70 W, 100 W, 150 W, and 250 W. The number of luminaires supplied from one circuit was determined based on the value of permissible active power losses. With the use of the DIALux program, projects of road lighting installation were developed. On this basis, energy performance indicators, electricity consumption, electricity costs, and CO 2 emissions were calculated for one-phase and three-phase installations. The obtained results indicate that an HPS lamp with EB is better than an HPS lamp with ECG in terms of energy quality, energy savings, and environmental impact. The results of this analysis are expected to assist in the choice of HPS lighting technology.
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Authors and Affiliations

Roman Sikora
1
ORCID: ORCID
Przemysław Markiewicz
1
ORCID: ORCID
Paweł Rózga
1

  1. Lodz University of Technology, Institute of Electrical Power Engineering, ul. Stefanowskiego 18/22, 90-924 Lodz, Poland
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Abstract

Warehouse and inventory management is a recurring issue in many of the different supply chains in diverse industries, where the constant changes in the markets have a direct impact on the management of warehouses and inventories, either generating over-stocks or shortages. This paper presents a case study on warehouse and inventory management control. The company under study was having problems in this area, where over-stocks were generated frequently, leading to various incidents, such as having to store finished and packaged product in unsuitable places, with the associated risk of deterioration. To deal with this problem, control tools based on the KPI (Key Performance Indicator) concept were developed. To this end, the corresponding problem and the information management process within the Supply Chain department had to be analyzed. In this case, it was observed that the databases were not synchronized, therefore strategies were proposed to systematize the collection and updating of data. In addition, to summarize the information, we proceeded to the implementation of an interactive form that facilitates the visualization and interpretation of the evolution of the process, and to be able to apply an efficient control on it, and thus to propose corrective actions supported by evidence.
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Authors and Affiliations

Micaela Marziali
Daniel Alejandro Rossit
Adrián Toncovich
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Abstract

Inaccurate estimation in highway projects represents a major problem facing planners and estimators, especially when data and information about the projects are not available, and therefore the need to use modern technologies that addresses the problem of inaccuracy of estimation arises. The current methods and techniques used to estimate earned value indexes in Iraq are weak and inefficient. In addition, there is a need to adopt new and advanced technologies to estimate earned value indexes that are fast, accurate and flexible to use. The main objective of this research is to use an advanced method known as artificial neural networks to estimate the TSPI of highway buildings. The application of artificial neural networks as a new digital technology in the construction industrial in Republic of Iraq is absolutely necessary to ensure successful project management. One model built to predict the TCSPI of highway projects. In this current study, artificial neural network model were used to model the process of estimating earned value indexes, and several cases related to the construction of artificial neural networks have been studied, including network architecture and internal factors and the extent of their impact on the performance of artificial neural network models. Easy equation was developed to calculate that TSPI. It was found that these networks have the ability to predict the TSPI of highway projects with a very outstanding saucepan of reliability (97.00%), and the accounting coefficients (R) (95.43%).

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Authors and Affiliations

Nidal A. Jasim
Shelan M. Maruf
Hadi S.M. Aljumaily
Faiq M.S. Al-Zwainy
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Abstract

IP scheduled throughput defined according to 3GPP TS 36.314 reflects user throughput regardless of traffic characteristics, and therefore has become one of the most important indicators for monitoring Quality of Service (QoS) of the end user in Evolved Universal Terrestrial Radio Access Network (E-UTRAN). However, networks built on a distributed architecture make the above definition impossible to be applied directly due to the implementation challenges. This paper gives an overview of the classical Long Term Evolution (LTE) architecture as opposed to Dual Connectivity (DC) topology and focuses on a novel method of solving the calculation issue with the IP scheduled throughput measurement in edge computing environment. Experimental results show a good agreement with the real end user perception.
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Authors and Affiliations

Arkadiusz Zięba
1
Martin Kollar
1
Krzysztof Tatarczyk
1
Jarosław Sadowski
2

  1. Nokia Solutions & Networks, Poland
  2. Gdansk University of Technology, Poland

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