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Number of results: 62
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Abstract

The paper aims at comparing forecast ability of VAR/VEC models with a non-changing covariance matrix and two classes of Bayesian Vector Error Correction – Stochastic Volatility (VEC-SV) models, which combine the VEC representation of a VAR structure with stochastic volatility, represented by the Multiplicative Stochastic Factor (MSF) process, the SBEKK form or the MSF-SBEKK specification.

Based on macro-data coming from the Polish economy (time series of unemployment, inflation and interest rates) we evaluate predictive density functions employing of such measures as log predictive density score, continuous rank probability score, energy score, probability integral transform. Each of them takes account of different feature of the obtained predictive density functions.

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Authors and Affiliations

Justyna Wróblewska
Anna Pajor
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Abstract

Households are the most significant group of consumers in the municipal and household sector in

Poland. In 2010-2016, households consumed annually from 8.9 to 10.8 million Mg of coal (77-81%

share in this sector).

As of the beginning of 2018, seven voivodships in Poland have already introduced anti-smog resolutions,

one has its draft, three are considering introduction of such resolutions. In the face of introducing

anti-smog resolutions, the analysis of coal consumption by households was conducted for a situation

where anti-smog resolutions will be introduced in all voivodships in Poland.

A forecast of hard coal consumption by Polish households in 2017-2030 was presented in the article.

Two scenarios differentiated in terms of calorific value of coal were taken into account: (i) concerned coal

with a calorific value of 24 MJ/kg (min. Q for eco-pea coal: grain size 5.0-31.5 mm), (ii) – coals with

a calorific value of 26 MJ/kg (Q recommended for use by producers of class 5 boilers).

In the perspective of 2030, the largest decrease in hard coal consumption can be expected (jointly)

in the voivodships of Śląskie, Dolnośląskie, Opolskie and Lubuskie. Under the assumptions made, in

relation to 2016, it may be reduced by half and fall from 2.8 to the level of 1.4-1.5 million Mg. The

smallest decreases in consumption may occur (jointly) in the Małopolskie, Lubelskie, Podkarpackie and

Świętokrzyskie voivodships – decrease by 16-22% and fall from 2.6 to approximately 1.9-2.0 million Mg.

On a national scale, coal consumption may decrease from the current 10.4 (2016) to around 6.3-6.8 million

Mg (a decrease of 30-35%).

Despite the decrease in hard coal consumption in the 2030 perspective, one should expect an increase

in demand for high quality coal dedicated to modern boilers (usually pea assortments) as well as qualified

coal fuels (mainly eco-pea coal).

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Authors and Affiliations

Katarzyna Stala-Szlugaj
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Abstract

There are many IT tools available on the market that carry out various types of forecasts in the gas industry. Programming evolves with the availability and capability of computers. IT tools support the user in engineering calculations, but also present the obtained results in an interesting visualization, e.g. in the form of interactive charts. The software can support making business decisions, which, in turn, can be used as business intelligence. In the era of digitization, huge metadata of measurements are created, so conducting data analyzes in the energy sector is very common. Moreover, rapidly evolving artificial intelligence creates new opportunities. The article presents a sample analysis of calculations using RStudio, an integrated development environment for the R language, a programming language for statistical calculations and graphics. The aim of the article is to present the possibility of using R language software to make a forecast and to determine the quality of forecasts. The article aims to present the possibility of making forecasts based on mathematical models available in R packages and the possibilities offered by the forecasting platform to readers. The article presents the U.S. market and has a particular focus on Natural Gas Residential Consumption in Pennsylvania (publicly available data from the U.S. Energy Information Administration). This dataset represents the monthly consumption of natural gas between 2015 and 2020. Forecasts were presented over a span of 12 months.
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Authors and Affiliations

Tomasz Chrulski
1
ORCID: ORCID

  1. Faculty of Drilling, Oil and Gas, University of Science and Technology AGH, Kraków, Poland
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Abstract

The essay presents an original application of using the coolhunting method to discover new trends in architecture and design. The ability to identify trends is tied in with the possibility of attaining an advantage over the competition with the use of new designs that can become hits on the market, gaining the favor of customers. The term coolhunting can be broadly defined as the pursuit of inspiration and the forecasting of the directions of development. Initially, the term was applied to fashion, but quickly spread to other spheres of activity, like music, the arts, lifestyle and finally, to architecture and design. The essay is a slightly altered and improved rendition of the author's article published in Zastosowania ergonomii. Wybrane kierunki badań ergonomicznych w roku 2014 . (ed. Charytonowicz J.), Publ. Polskie Towarzystwo Ergonomiczne PTErg, o/Wrocław, 2014, p. 289-304. The method outlined therein is the result of research conducted under the author's supervision at the Institute of Architecture and Spatial Planning of the Poznań University of Technology between the years 2012 and 2014.

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Authors and Affiliations

Wojciech Bonenberg
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Abstract

A forecast of the negative impact exerted on the environment by selected trace elements in “Bełchatów” Power Plant has been prepared on the basis of the results of investigations into these elements’ distribution carried out as part of earlier research on coal from “Bełchatów” Field and the data on updated analyses of the content of these elements in 55 brown coal samples from test boreholes. Work in “Bełchatów” Power Plant, which is supplied with coal from “Szczerców” Field, will be accompanied by trace elements transfer. On the basis of the conducted investigations it has been found that the biosphere is most threatened by mercury emissions. As shown by the presented results of analyses and calculations, the emissions of mercury in “Bełchatów” Power Plant are low. Mercury is accumulated chiefl y in gypsum produced in the FGD plant. The content of mercury in slag and ash is low.
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Authors and Affiliations

J. Konieczyński
E. Cieślik
B. Komosiński
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Abstract

Traffic related noise is currently considered as an environmental pollution. Paper presents results of multidirectional study attempting to serve urban traffic without the need to erect noise barriers interfering urban space. Initial concept of the road expansion included construction of 1000 m of noise barriers dividing city space. Improvement in the acoustic conditions after construction completion is possible due to the applied noise protection measures: vehicle speed limit, smooth of traffic flow, use of road pavement of reduced noise emission and the technical improvement of the tramway.

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Authors and Affiliations

K.J. Kowalski
A.J. Brzeziński
J.B. Król
P. Radziszewski
Ł. Szymański
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Abstract

While personality is strongly related to experienced emotions, few studies examined the role of personality traits on affective forecasting. In the present study, we investigated the relationships between extraversion and neuroticism personality traits and affective predictions about academic performance. Participants were asked to predict their emotional reactions two months before they will get their results for one important exam. At the same time, personality was assessed with the Big Five Inventory. All the participants were contacted by a text message eight hours after that the results were available, and they were requested to rate their experienced affective state. Results show moderate negative correlations between neuroticism and both predicted and experienced feelings, and that extraversion exhibits a weak positive correlation with predicted feelings, but not with experienced feelings. Taken together, these findings confirm that extraversion and neuroticism shape emotional forecasts, and suggest that affective forecasting interventions based on personality could probably enhance their efficiencies.

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Authors and Affiliations

Michel Hansenne
Virginie Christophe
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Abstract

The paper presents a model of the sealing process in kinematic pairs of hydraulic cylinders with elastic seals and an analytical form of this model based on the results obtained by the author. The prepared model distinguishes rheological parameters, allowing one to determine the criteria of a correct course of the sealing process and to forecast the operating time for the seals. Exemplary test results and their analysis are presented, too. It results from the analysis that leakage efficiency through the seal is dependent on the sealing pressure determined by the parameter 8, and it is unstable in relation to this parameter. Basing on this fact, the author determined conditions of hydrodynamic convection of the sealing and elaborated an analytical model of the sealing process including roughness of the piston rod surface as well as the seal flexibility.
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Authors and Affiliations

Czesław Pazoła
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Abstract

The aim of the paper is to point out that the Monte Carlo simulation is an easy and flexible approach when it comes to forecasting risk of an asset portfolio. The case study presented in the paper illustrates the problem of forecasting risk arising from a portfolio of receivables denominated in different foreign currencies. Such a problem seems to be close to the real issue for enterprises offering products or services on several foreign markets. The changes in exchange rates are usually not normally distributed and, moreover, they are always interdependent. As shown in the paper, the Monte Carlo simulation allows for forecasting market risk under such circumstances.

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Authors and Affiliations

Jan Kaczmarzyk
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Abstract

In Poland, there is a growing awareness of the need to change the sources of electricity and heat. An expression of this is the adoption of the document entitled Poland’s Energy Policy until 2040 (PEP 2040) in February 2020 by the Council of Ministers. The goal of the Polish Energy Policy until 2040 is “energy security – ensuring the competitiveness of the economy, energy efficiency and reducing the environmental impact of the energy sector – taking into account the optimal use of own energy resources”. In PEP 2040, the previous assumptions of the state’s long-term energy policy were amended and an increase in the use of low- or non-emission sources was declared. In addition, the energy policy guidelines contain forecasts for the production of steam coal and the demand for this raw material. Based on the provisions of the document, as well as forecasts of the coal-production volume prepared by the authors and the assessments of experts in the fields related to energy and mining, the article contains considerations on the validity of the developed forecasts together with the determination of the production capacity of domestic mining enterprises in terms of covering the demand for steam coal used for the production of electricity and heat. It is planned, inter alia, that blocks of coal-fired power plants will be decommissioned and, in their place, there is to be the expansion of solar and wind energy and the commissioning of the first blocks of a nuclear power plant. Such activities, which cause a decrease in the demand for coal, are also related to the plans of changes in the functioning of mining enterprises – there will be successive closures of individual mines and mining plants.
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Authors and Affiliations

Marian Czesław Turek
1
Patrycja Bąk
2
ORCID: ORCID

  1. Central Mining Institute, Katowice, Poland
  2. AGH University of Science and Technology, Kraków, Poland
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Abstract

Weather forecasting requires knowledge of the laws of atmospheric movement. Apart from classic fluid mechanics, we must consider the rotational motion of our planet, the differential heating of its surface through the absorption of solar radiation, as well as water evaporation and condensation processes.

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Authors and Affiliations

Lech Łobocki
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Abstract

The Convolutional Neural Network (CNN) model is one of the most effective models for load forecasting with hyperparameters which can be used not only to determine the CNN structure and but also to train the CNN model. This paper proposes a framework for Grid Search hyperparameters of the CNN model. In a training process, the optimal models will specify conditions that satisfy requirement for minimum of accuracy scores of Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE) and Mean Absolute Error (MAE). In the testing process, these optimal models will be used to evaluate the results along with all other ones. The results indicated that the optimal models have accuracy scores near the minimum values. Load demand data of Queensland (Australia) and Ho Chi Minh City (Vietnam) were utilized to verify the accuracy and reliability of the Grid Search framework.
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Bibliography

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Authors and Affiliations

Thanh Ngoc Tran
1

  1. Faculty of Electrical Engineering Technology, Industrial University of Ho Chi Minh City, 12 Nguyen Van Bao, Ward 4, Go Vap District, Ho Chi Minh City, Vietnam
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Abstract

Changes in capacity of water reservoir Cedzyna during its exploitation since 1972 till 2003 are presented in the paper. Analyses were based on cross sections of the reservoir’s basin from before its fulfillment (1967) and those measured with the echo sounder Ceeducer in 2003. Silting of reser-voir was predicted based on empirical methods. The volume of reservoir was found to decrease by 112.8 thousand m3 during 31 years of its exploitation and reservoir’s life span was assessed at 685 years. An error analysis was additionally made of calculating the surface area of a cross section at varying number of sounding sites. It was found that there was no need to note too many coordinates and depths and for the Cedzyna reservoir the distance between measurement sites up to 16 m was sufficient.

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Authors and Affiliations

Jarosław Bodulski
Jarosław Górski
ORCID: ORCID
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Abstract

Knowledge about future traffic in backbone optical networks may greatly improve a range of tasks that Communications Service Providers (CSPs) have to face. This work proposes a procedure for long-term traffic forecasting in optical networks. We formulate a long-terT traffic forecasting problem as an ordinal classification task. Due to the optical networks’ (and other network technologies’) characteristics, traffic forecasting has been realized by predicting future traffic levels rather than the exact traffic volume. We examine different machine learning (ML) algorithms and compare them with time series algorithms methods. To evaluate the developed ML models, we use a quality metric, which considers the network resource usage. Datasets used during research are based on real traffic patterns presented by Internet Exchange Point in Seattle. Our study shows that ML algorithms employed for long-term traffic forecasting problem obtain high values of quality metrics. Additionally, the final choice of the ML algorithm for the forecasting task should depend on CSPs expectations.
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Authors and Affiliations

Krzysztof Walkowiak
1
Daniel Szostak
1
Adam Włodarczyk
1
Andrzej Kasprzak
1

  1. Wroclaw University of Science and Technology, Poland
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Abstract

Metallurgy is one of the key industries both in Russia and in the world. It has a significant influence on the situation in related industries. Therefore, the current state analysis of ferrous metallurgy production and its formation based on the short-term technological forecast is essential. Based on the foregoing, the research was aimed at analyzing the current state of ferrous metallurgy production in Russia and the impact of the COVID-19 pandemic on the prospects for industry development in the short term. The research studies the state of the ferrous metallurgy production in Russia and abroad before the COVID-19 pandemic, as well as the volume of industrial production in ferrous metallurgy and the industry structure. The COVID-19 pandemic has triggered a serious global recession, necessitating an analysis of the forecast for the development of the ferrous metallurgy industry. The research concludes that the Russian ferrous metals market is so far affected to a lesser extent compared to the European one.
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Bibliography

[1] Ryabov, I.V. (2013). Institutional factors of economic development in the steel industry in the Russian Federation. Ekonomika: vchera, segodnya, zavtra. 7-8, 59-71.
[2] Shatokha, V. (2016). Post-Soviet issues and sustainability of iron and steel industry in Eastern Europe. Mineral Processing and Extractive Metallurgy. 126, 1-8.
[3] MIT Emerging Trends Report (2013). Cambridge, MA: Massachusetts Institute of Technology. Retrieved from http://2013.forinnovations.org/upload/MIT_Technology_Review.pdf.
[4] Cuhls, K. (2003). From forecasting to foresight processes. new participative foresight activities in Germany. Journal of Forecasting. 22, 93-111.
[5] Harrington, E.C.Jr. (1965). The desirability function. Industrial quality control. 21(1), 494-498.
[6] Profile. 2017/2018. World steel association. Retrieved from https://www.worldsteel.org/en/dam/jcr:cea55824-c208-4d41-b387-6c233e95efe5/worldsteel+Profile+2017.pdf.
[7] World Steel Association (2018). Monthly crude steel and iron production statistics. Retrieved from https://www.worldsteel.org/publications/bookshop/productdetails.~2018-Monthly-crude-steel-and-iron-productionstatistics~PRODUCT~statistics2018~.html.
[8] Metalinfo.ru (2018). China continues to cut off excessive capacity. Retrieved from http://www.metalinfo.ru/ru/news/100765.
[9] World Steel Association (2017). Steel Statistical Yearbook 2017. Retrieved from https://www.worldsteel.org/en/dam/jcr:3e275c73-6f11-4e7f-a5d8-23d9bc5c508f/Steel% 2520Statistical%2520Yearbook%25202017_updated%2520version090518.pdf.
[10] World Steel Association (2017). 50 years of the World Steel Association. World Steel Association. Retrieved from https://www.worldsteel.org/en/dam/jcr:80fe4bd6-4eff-4690-96e6-534500d35384/50%2520years%2520of%2520worldsteel_EN.pdf.
[11] Dudin, M.N., Bezbakh, V.V., Galkina, M.V., Rusakova, E.P., Zinkovsky, S.B. (2019). Stimulating Innovation Activity in Enterprises within the Metallurgical Sector: the Russian and International Experience. TEM Journal. 8(4), 1366-1370.
[12] Kharlamov, A.S. (2012). Competitiveness issues of metallurgy. Position of Russia. Monograph. Moscow: Nauchnaya Kniga.
[13] Golubev, S.S, Chebotarev, S.S., Sekerin, V.D. & Gorokhova, A.E. (2017). Development of Employee Incentive Programmes regarding Risks Taken and Individual performance. International Journal of Economic Research. 14(7), 37-46.
[14] Deloitte (2020). Overview of the ferrous metallurgy market. Retrieved from https://www2.deloitte.com/ru/ru/pages/research-center/articles/overview-of-steel-and-ironmarket-2020.html.
[15] Katunin, V.V., Zinovieva, N.G., Ivanova, I.M., Petrakova, T.M. (2021). The main performance indicators of the ferrous metallurgy of Russia in 2020. Ferrous metallurgy. Bulletin of Scientific. Technical and Economic Information. 77(4), 367- 392. DOI: https://doi.org/10.32339/0135-5910-2021-4-367-392.
[16] National Credit Ratings (NCR) (2021). The metamorphoses of the pandemic. The forecast of recovery of the Russian economy branches as of June 2, 2021. Analytical Research. June 2, 2021. Retrieved from https://www.ratings.ru/files/research//corps/NCR_Recovery_Jun2021.pdf 24.
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Authors and Affiliations

S.S. Golubev
1
V.D. Sekerin
1
A.E. Gorokhova
1
D.A. Shevchenko
1
A.Z. Gusov
2

  1. Moscow Polytechnic University, Bolshaya Semenovskaya Street, 38, Moscow, 107023, Russian Federation
  2. Peoples Friendship University of Russia (RUDN University), Miklukho-Maklaya Street, 6, Moscow, 117198, Russian Federation
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Abstract

Covering a wide area by a large number of WiFi networks is anticipated to become very popular with Internet-of-things (IoT) and initiatives such as smart cities. Such network configuration is normally realized through deploying a large number of access points (APs) with overlapped coverage. However, the imbalanced traffic load distribution among different APs affects the energy consumption of a WiFi device if it is associated to a loaded AP. This research work aims at predicting the communication-related energy that shall be consumed by a WiFi device if it transferred some amount of data through a certain selected AP. In this paper, a forecast of the energy consumption is proposed to be obtained using an algorithm that is supported by a mathematical model. Consequently, the proposed algorithm can automatically select the best WiFi network (best AP) that the WiFi device can connect to in order to minimize energy consumption. The proposed algorithm is experimentally validated in a realistic lab setting. The observed performance indicates that the algorithm can provide an accurate forecast to the energy that shall be consumed by a WiFi transceiver in sending some amount of data via a specific AP.

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Authors and Affiliations

Atef Abdrabou
Mohamed Darwish
Ahmed Dalao
Mohammed AlKaabi
Mahmoud Abutaqiya
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Abstract

The aim of the study was to indicate the procedure of using laboratory physical model tests of scour around bridge piers for the purposes of determining the potential scour of a riverbed on field bridge crossings. The determination of the uniform modeling scale coefficient according to the criterion of reliable sediment diameter limits the application of the results of tests on physical models to selected types of sediment. The projected depths of scouring of the riverbed at the pier in nature were determined for an object reproduced in the scale of 1:15 determined from the relationship of flow resistance, expressed by hydraulic losses described by the Chézy velocity coefficient, the value of which, in the model and in nature, should be the same. Expressing the value of the Chézy velocity coefficient with the Manning roughness coefficient and introducing the Strickler parameter, it was shown that the coarse sand used in the laboratory bed models the flow resistance corresponding to the resistance generated by gravel in nature. The verification of the calculated size of scouring was based on popular formulas from Russian literature by Begam and Volčenkov [16], Laursen and Toch’s [20] from the English, and use in Poland according to the Regulation ... (Journal of Laws of 2000, No. 63, item 735) [32].
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Bibliography


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[11] G. J. C. M. Hoffmans, H. J. Verheij, “Scour Manual,” Rotterdam: A. A. Balkema, 1997.
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[15] J. Schalko, C. Lageder, V. Schmocker, V. Weitbrecht, R. M. Boes, “Laboratory Flume Experiments on the Formation of Spanwise Large Wood Accumulations: Part II–Effect on local scour,” Water Resources Research, vol. 55, pp. 4871–4885, May 2019. https://doi.org/10.1029/2019WR024789
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Authors and Affiliations

Sławomir Bajkowski
1
ORCID: ORCID
Marta Kiraga
1
ORCID: ORCID
Janusz Urbański
1
ORCID: ORCID

  1. Warsaw University of Life Sciences WULS-SGGW, Institute of Civil Engineering, ul. Nowoursynowska 159, 02-787 Warsaw, Poland
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Abstract

The size and distribution of water demand within a given structural unit is the basis for the proper operation and planning of the expansion and modernization of the water supply system’s elements. In rural areas, particularly in municipalities adjacent to urban-industrial agglomerations, a change in the use of tap water has been increasingly observed. The water consumption for animal breeding or agricultural use, typical of these areas, has been decreasing and even disappearing. Water has been increasingly used for domestic purposes in single- and multi-family housing as well as for other purposes such as watering lawns and filling residential swimming pools. Taking this into account, this paper presents observations regarding daily water consumption in a municipality adjacent to Wrocław together with an analysis of the possibility of using the exponential smoothing method for the short-term forecasting of daily water consumption. The analyses presented in this paper were carried out using STATISTICA 13 software.
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Authors and Affiliations

Wojciech Cieżak
1
ORCID: ORCID
Małgorzata Kutyłowska
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Faculty of Environmental Engineering, Wybrzeze Wyspianskiego 27, 50-370 Wrocław, Poland
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Abstract

Coronavirus infection (COVID-19) is a highly infectious disease of viral etiology. SARS-CoV-2 virus was first identified during the investigation of the outbreak of respiratory disease in Wuhan, China in December 2019. And already on March 11, 2020 COVID-19 in the world was characterized by the WHO as a pandemic. In Ukraine the situation with incidence COVID-19 remains difficult. The purpose of this study is to to develop a mathematical forecasting model for COVID-19 incidence in Ukraine using an exponential smoothing method. The article analyzes reports on basic COVID-19 incidence rates from 29.02.2019 to 01.10.2021. In order to determine the forecast levels of statistical indicators that characterize the epidemic process of COVID-19 the method of exponential smoothing was used. It is expected that from 29.02.2019 to 01.10.2021 the epidemic situation of COVID-19 incidence will stabilize. The indicator of “active patients” will range from 159.04 to 353.63 per 100 thousand people. The indicator of “hospitalized patients” can reach 15.43 and “fatalities” — 1.87. The use of the method of exponential smoothing based on time series models for modeling the dynamics of COVID-19 incidence allows to develop and implement scientifically sound methods in order to prevent, quickly prepare health care institutions for hospitalization.
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Authors and Affiliations

Nina Malysh
1
Alla Podavalenko
2
Olga Kuzmenko
3
Svitlana Kolomiets
3

  1. Department of Infectious Diseases with Epidemiology, Sumy State University, Rymskogo-Korsakova 2, Sumy, Ukraine
  2. Department of Hygiene, Epidemiology and Occupational Diseases, Kharkiv Medical Academy of Postgraduate Education, Amosova, 58, Kharkiv, Ukraine
  3. Department of Economic Cybernetics, Sumy State University, Rymskogo-Korsakova 2, Sumy, Ukraine
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Abstract

In the article, mathematical modeling methods are used to study the main trends and macroeconomic determinants of the electric car market development in 2011–2018 on the example of the US. The determinants include economic (GDP), socio-economic (household income), energy (electricity use), and environmental (СО2 emissions) factors. The authors justify the role of electric transport in strengthening national energy security due to the transition to renewable energy technologies and the reduction of fossil fuel use. Based on the constructed linear regression equations, a weak relationship has been revealed between the number of electric vehicles sold and the environmental factor, which can be explained by the small share of electric cars in the US market. The formed multifactor linear model showed a positive impact of both the country’s GDP growth and electricity consumption increase on the number of electric vehicles sold. However, the rise in household incomes negatively influences market development due to insufficient consumer awareness of the electric transport operation benefits, an underdeveloped network of electric vehicle charging stations, etc. Based on the obtained multifactor model, the authors have built optimistic, optimal and pessimistic scenarios for the US electric vehicle market deployment for the next five years. In order to implement the most favorable scenarios, recommendations for market development factors’ management have been made. The results of the study can be used to improve public policy in the US transport and energy sectors, as well as in other countries to optimize the fuel and energy balance, strengthen the energy independence of states by developing clean transport and adapting the model to national specifics.

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Authors and Affiliations

Iryna Sotnyk
ORCID: ORCID
Daniil Hulak
ORCID: ORCID
Oleksandr Yakushev
ORCID: ORCID
Oksana Yakusheva
ORCID: ORCID
Olha V. Prokopenko
Andrii Yevdokymov
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Abstract

The article analyzes the structure of energy resources, as a result of which the reasons for their irrational use in the Ukrainian economy are revealed. It has been established that during 2014–2018 there was a decrease in demand for traditional types of fuel and energy resources (FER), except for coal. The components of the process of supply and consumption of fuel and energy resources have been formed and detailed, and an integrated approach to their rational use has been developed, which will reduce the loss of energy resources and increase their efficiency. The author’s approach is used in the form of visualized schemes for organizing the process of the rational use of energy resources, which will contribute to the implementation of an effective energy saving policy of the state, ensuring the competitive advantages of domestic enterprises, increasing their competitiveness, improving the economic and energy security of Ukraine. The expediency of constructing deterministic economic models for providing the Ukrainian economy according to different (adaptive and multiplicative) convolutions was substantiated and proved, on the basis of which a forecast and assessment of the energy independence of the Ukrainian economy until 2035, taking into account fuel and energy resources, was proposed. Based on the calculations, it was established that the state of energy independence of Ukraine is insufficient.
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Authors and Affiliations

Uliana Andrusiv
1
ORCID: ORCID
Halyna Zelinska
2
ORCID: ORCID
Olga Galtsova
3
ORCID: ORCID
Halyna Kupalova
4
ORCID: ORCID
Nataliia Goncharenkо
4
ORCID: ORCID

  1. Department of Economics Theory and Management, Ivano-Frankivsk National Technical University of Oil and Gas, Ukraine
  2. Ivano-Frankivsk National Technical University of Oil and Gas, Ukraine
  3. Classical Private University, Ukraine
  4. Taras Shevchenko National University of Kyiv, Ukraine
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Abstract

Coal production in 2018 increased by 3.3% and amounted to 7.81 million tons. Compared to 2010, it increased by 620 million tons. The structure of coal production in the world is very stable in the analyzed period of 2010–2018. Steam coal dominates in production with a share of 77%. Since 1990, the share of coal in the consumption of primary energy carriers has fallen by 3% in the global economy. In the EU, the share of coal in the consumption of primary energy carriers is more than twice lower than in the world, and in 2018 amounted to 13%. BP estimates the sufficiency of coal proven reserves based on 2018 data for the next 132 years. For oil and gas, they are estimated at 51 years. The decline in hard coal production in the European U nion can be dated almost continuously since 1990, which has decreased by 74%. In 2018, 74 million tons of coal were produced in the EU. In 2018, hard coal consumption in EU countries dropped to 226 million tons, i.e. by 20.6%.

In 2018, global trade in steam coal amounted to 1.14 billion tons. The situation in China is crucial for the international coal market. The slight change in the import policy of this country significantly affects the situation in international trade in steam coal. In 2019, coal prices (at Newcastle, Richards Bay, ARA ports) dropped by an average of 23 U SD/ton. The average decreases for these three indices were 33%. The prices of steam coal in the forecasts presented in the paper are under pressure of the falling demand.

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Authors and Affiliations

Zbigniew Grudziński
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Abstract

The work contains discussions and simulation analyses of the expectation formation processes, taking account of the data revisions. In particular, it contains results of simulations examining statistical properties of the rationality tests and extrapolation processes, with particular focus on their behaviour in the case of short samples and data with measurement errors. The conclusions indicate that the rationality test based on the optimal regression and the proposed adaptive and accelerating tests are the most efficient and flexible. The tests showcasing best properties have been applied to a new set of macroeconomic forecasts for Poland. The results show that there are no grounds for rejecting the hypothesis on the rationality of forecasts derived from the National Bank of Poland (NBP) and the Organisation for Economic Cooperation and Development; however, this property was rejected for the European Commission. What is more, the comparative analysis indicates that only the national institution (NBP) may potentially aim the final readings of the macroeconomic data as the forecasting target. Finally, it transpires that the extrapolative models, albeit simple and intuitively interpreted, generally fail to correctly explain the forecast formation processes regarding the Polish economy.
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Authors and Affiliations

Paulina Ziembińska
1

  1. University of Warsaw, Faculty of Economic Sciences, Warsaw, Poland
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Abstract

The methane hazard is one of the most dangerous phenomena in hard coal mining. In a certain range of concentrations, methane is flammable and explosive. Therefore, in order to maintain the continuity of the production process and the safety of work for the crew, various measures are taken to prevent these concentration levels from being exceeded. A significant role in this process is played by the forecasting of methane concentrations in mine headings. This very problem has been the focus of the present article. Based on discrete measurements of methane concentration in mine headings and ventilation parameters, the distribution of methane concentration levels in these headings was forecasted. This process was performed on the basis of model-based tests using the Computational Fluid Dynamics (CFD). The methodology adopted was used to develop a structural model of the region under analysis, for which boundary conditions were adopted on the basis of the measurements results in real-world conditions. The analyses conducted helped to specify the distributions of methane concentrations in the region at hand and determine the anticipated future values of these concentrations. The results obtained from model-based tests were compared with the results of the measurements in realworld conditions. The methodology using the CFD and the results of the tests offer extensive possibilities of their application for effective diagnosis and forecasting of the methane hazard in mine headings.

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Authors and Affiliations

Jarosław Brodny
Magdalena Tutak

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