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  • Malyshev, Nikolay V.; Koroviakovskii, Evgenii K.; Rostovceva, Svetlana A. (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The article presents the analysis of options for a transshipment terminal system with consideration of Russian transport system development. The aim is to determine the premises and possible problems, considering human absence, in the technological process at an inland container terminal. Statistical methods are used to analyze the market of robotic automation and the perspective for unmanned technology introduction. Simulation modeling of inland container terminal operation with various types of equipment, to study the applicability of robotic automation. The choice of modeling equipment results from the impossibility of completing an experiment on the real object, difficulties of analytical modeling (the system contains casual relations, nonlinear logic, stochastic variables), and the necessity to analyze the system’s time behavior. Consideration of robotic automation in a terminal warehouse complex is of particular importance due to technological progress followed by the freight terminal to be an area with highly organized technological processes and the need for highly paid specialists.
  • Gnaciński, Piotr; Pepliński, Marcin; Hallmann, Damian (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper deals with the effect of voltage subharmonics on power losses and heating of an induction motor. An increase in power losses in stator and rotor windings and their impact on windings temperature is presented for subharmonics of various frequencies. The results of this study’s investigations are provided for subharmonics occurring as a single power quality disturbance and combined with voltage deviation. The appropriate electromagnetic computations were performed with the finite element method, and thermal ones – with an analytical method.
  • Kotowicz, Janusz; Brzęczek, Mateusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The paper presents technologies currently being developed for methanol production and its applications. Particular attention was paid to energy storage technology in the form of “renewable” methanol, which is produced from hydrogen generated from surplus energy from renewable energy sources and from captured CO2. The global methanol market was characterized, i.e. global demand, major producers and global demand for products made from methanol. The installation of methanol production and purification with stoichiometry as well as the methodology for assessing the efficiency of such an installation are also presented. The results of the analysis of such an installation were discussed in accordance with the methodology given.
  • Tvalchrelidze, Alexander G.; Silagadze, Avtandil (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    At the beginning of the COVID-19 coronavirus global pandemic, the oil market was crushed. In this period, the oil market was correlated with COVID-19 coronavirus world infection cases: more infected cases resulted in low oil prices, and the negative correlation between these two indices was very strong. Different factors determined the increase in both crude oil price and the number of oil futures contracts after April 20. Firstly, oil prices were driven by the coronavirus mortality rate, rather than by the absolute number of infection cases. The decisive driver for oil prices in the medium-term became pandemic development trends, instead of the actual epidemiological situation. This statement is proven by the statistical regression model of the interdependence between oil prices and COVID-19 coronavirus world mortality rate. Secondly, a gradual stable decrease in the coronavirus world mortality rate created an environment for the gradual restart of the world economy. Thirdly, the coronavirus mortality rate analysis provides investors with tangible guidelines to assess the medium-term sustainability of futures markets and, therefore, to elaborate investment strategies. Fourthly, after April 20, the oil market gradually achieved equilibrium, which is proven by a restored correlation between oil prices and the Euro-to-U.S. Dollar exchange rate. Three-month tendencies provide tangible guidelines for an optimistic forecast of the oil the market and maritime tanker business for the end of 2020 and all of 2021. So long as a new wave of COVID-19 does not dramatically increase mortality rates, the oil and maritime tanker trade market will regain the equilibrium it lost at the end of January.
  • Grenčík, Juraj; Galliková, Jana; Volna, Peter (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This study proposes a new methodology for the accurate risk assessment of railway freight wagons that has real-world applications in the operation and maintenance of freight vehicles. The paper specifically focuses on the analysis of posterior reliability calculation methods using Weibull’s reliability model to calculate reliability indicators by which the probability of occurrence of individual failures can be estimated. The consequences of failure are calculated through an existing system from the General contract used for freight wagons (AVV). The formula for calculating the risk value is based on a classical risk theory, where the risk is defined as a combination of the occurrence of a negative phenomenon and the severity of its consequence. The reasoning for this approach was in an effort to maintain simplicity and clarity for potential users in practice. This is based on the information gathered in examining the current state of risk management in the sector of railway vehicles in Slovakia. The data used for risk calculations were taken from a maintenance workshop in Slovakia to provide a realistic picture of the failure rates of freight wagons. The proposed methodology uses historical data for prediction of reliability for the next years. Based on the reliability being a function of time, the risk associated with it is variable, increasing with time. These findings have broader implications for the maintenance systems taken appropriate maintenance actions necessary with respect to increased risk.
  • Trojanowski, Piotr (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The constant development of transport systems and the extensive activities related to the safety of its users necessitate the development of methods for assessing the impact of road infrastructure expansion/modernization on road safety. The objective of this paper is to elaborate the concept of such an assessment, which will form part of the author’s activities aimed at creating a methodology for a comprehensive analysis of the operational reliability of transport systems. The concept of assessing the impact of road infrastructure development on road safety presented in this paper refers to the GAMAB and Road Safety Impact Assessment methods from the subject literature. Our method is based on a comparative analysis of the condition of road infrastructure before and following its expansion/modernization, based on commonly available data, which constitutes the main advantage of the concept presented in this paper. Furthermore, the coefficients for occurrence of adverse road events were determined, and then conclusions drawn on this basis. The acquired results constitute an argument for the correctness of the presented concept.
  • Galliková, Jana; Grenčík, Juraj; Barta, Dalibor; Barlok, Matej (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This study investigates FMECA analysis and its potential use in improving the reliability and maintenance of the thermal deburring machine in a manufacturing company located in Slovakia. In the beginning, an overview of the FMEA/FMECA methods and their utilization for increased reliability are discussed. As a practical solution, the deburring machine EXTRUDE HONE TEM P-350 was chosen. Functions of its systems and components, thermal deburring process, its characteristics and in practice application are described. Maintenance policy in the company and the current state of maintenance of the machine are also presented. In addition, the study includes failure analysis which evaluates the riskiest systems of the machine. One element, hydraulic unit, is a subject for the FMECA analysis which envisions the assessment of the current failure modes using risk priority number (RPN) and proposals of prevention and detection action reducing the level of RPN. The final section focuses on influencing and improving maintenance and summarizing the potential benefits of FMECA Analysis for company and machine operation.
  • Załoga, Elżbieta; Stępień, Grzegorz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Digitisation of transport is a tool for achieving the European Union’s political goals included in the Digital Single Market Strategy for Europe. For rail transport, digital innovation is required to increase its competitiveness. One of the tools of the digital transformation of railways is 5G networks, the fifth generation of wireless communication systems. The purpose of this article is to present the benefits of implementing 5G network for railway operators. Focus was placed on its innovative features, such as ultra-fast access to Internet services, very high connection reliability, and extremely low data transmission delays. Examples of new services for railway operators based on the capabilities of 5G networks were presented. This article describes the unique functions of the 5G network in which resources can be flexibly allocated depending on current traffic needs thanks to the network slicing function, e.g., for services of key importance to rail traffic and commercial services for other market segments. Roadmap proposals for transforming the current rail communication network infrastructure towards the target FRMCS system are presented. The analysis was based on source materials from Nokia Corporation, available literature, EU documents and regulations, as well as institutional studies of the railway sector.
  • Tepe, Resul; Kayiran, Burhan; Açik, Abdullah (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    One of the most important factors affecting international trade is exchange rate fluctuations. To date, studies that have analyzed the effect of exchange rates have shown that the effect can vary from sector to sector and from country to country. The fact that this relationship has not been extensively studied in the fisheries industry is the motivation for this study. In this regard, the aim of this study is to determine whether changes in the real exchange rates of countries affect their fisheries production levels. Accordingly, we used the causality test developed by Emirmahmutoglu and Kose (2011), which takes into account both cross-sectional dependencies and heterogeneity. The data set used in this study consisted of 27 annual observations from 38 countries from 1990–2016. The results revealed that changes in the real exchange rate affected fisheries production. This situation shows that changes in exchange rates may affect the international demand for fisheries and serve as a source of motivation for producers.
  • German-Galkin, Sergey (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Analytical research methods to determine the power characteristics of generator sets with vector control in an asynchronous squirrel-cage machine were developed and used to calculate the energy characteristics of generator sets with the field-oriented control (FOC) and direct torque control (DTC). The analytical calculations showed that a generator set with direct torque control had slightly better energy characteristics. Confirmation of the analytical calculation results was carried out using simulation models developed in the MATLAB-Simulink package with an environment Simscape Power System.
  • Starczewska, Weronika; Uhl, Tadeus (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In today’s production and service systems, the management process plays a primary role. Analysis of the management process allows the detection of weaknesses and strengths in analyzed systems. This paper analyses production line management processes. For one literature example, a queuing model of a selected production line was built, and its performance and reliability were analyzed. The modelling attempt undertaken here was designed to determine whether queuing theory is suitable for modelling production line processes. Confirmation of this thesis would be a novelty in this field.
  • Ziętek, Ryszard; Woźniak, Marcin (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In this paper, a mini-crane control system using an exoskeleton based on programmable logic technology is presented. The first stage was to identify the parameters of the mini-crane and exoskeleton sub-assemblies. Then, individual crane and exoskeleton control subsystems were designed based on cascade regulation. The final stage was to connect these subsystems into the master-slave control system using the manipulator’s kinematics equations. Parallel processing was used to minimize delays in the control system. Analysis of the results showed that the difference between the set and measured crane position was small.
  • Pluskota, Przemysław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The development of any region is a complex phenomenon that depends on various factors, including a financial infrastructure that supports enterprises and other business entities. Issues related to the impact of financial institutions on economic development are often addressed in the academic literature. Some researchers claim that the development of financial institutions and instruments leads to the development of the entire country, indicating a close correlation between them. Others confirm this interdependence; however, they argue that it is non-linear and it depends on other factors, such as the country’s level of economic development, as well as how advanced its financial infrastructure is. Few studies have addressed the impact of regional financial institutions on regional development, and although macroscale studies have been implemented on the micro-level, they don’t necessarily reflect any interdependencies. Regional financial infrastructure plays an important role in regional development, and the Regional Development Funds (RDFs) that have recently appeared in some voivodeships confirm this interdependency. These institutions are likely to become integrators and stimulators of regional financial markets, and RDFs can become entities that manage capital that can be appreciated in many banks and exert a tangible effect on regional financial policies. At the same time, they will level any market flaws in terms of access to capital by micro-, small, and medium enterprises, as well as running growth-promoting policies tailored to the specific regional needs.
  • Magryta, Beata; Kołowrocki, Krzysztof (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    A method for reliability optimization, which is relevant for critical infrastructure activity governed by operational processes, is presented and applied to a port oil terminal. The optimal values for the reliability and resilience indicators related to the operation, are determined for this critical type of infrastructure. Simple suggestions regarding optimized infrastructural operation strategies are formulated and implemented towards reorganizing the port oil terminal processes in order to maximize its lifetime in defined reliability states.
  • Kotkowska, Diana (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents the capabilities of a SAR module during rescue operation planning and control. The Navi- Harbour SAR module was used during an exercise, which enabled an operator to plan and monitor the rescue operations of selected water areas. To present the basic capabilities of this module, we prepared a case for the SAR action for a man overboard in the Baltic Sea using actual available SAR resources in this area. For the basic assumptions of the scenario, a research plan was developed that included an assessment of the most probable position of a threatened unit, taking into account the weather conditions in this area.

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