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This study presents a comprehensive analysis using the finite element method (FEM) to examine and evaluate the behavior of fuel carrier ship structure. Sandwich panels are effective structures for use in ship structures due to their lightweight yet robust nature. Sandwich panels used in ship structures have various core shapes, such as hexagonal, circular, and square, as needed. The sandwich panel structure can be widely implemented in ship construction, for example, on the deck, hull, and bulkhead of the ship’s cabin. Hydrogen is an alternative fuel that can replace fossil fuels. In this modern era, hydrogen is high valuable energy commodity, so accidents involving carrier ships could have significant consequences. Hydrogen is produced from liquefied natural gas (LNG), so if a leak occurs, for instance, in a storage tank or fuel tank, it has the potential to lead to accidents such as fires. Corrosion is a significant concern for the maritime industry, as it can jeopardize the structural integrity of these vessels and pose substantial safety and environmental risks. In this research, FEM was utilized to model and simulate the effects of corrosion on hydrogen carrier ships when exposed to fire, considering various environmental and operational factors. Through a systematic investigation, it is aimed to gain insights into the impact of corrosion on ship structural components during fires, such as hulls and storage tanks. The result of this study will contribute to improving corrosion and fire mitigation strategies, ensuring the safety and longevity of hydrogen and LNG carrier ships, and supporting the sustainable transportation of hydrogen to meet global energy demands. No research has been conducted on the structural behavior resulting from hydrogen fires and corrosion simultaneously. To achieve this, it is assumed to use the corrosion properties of steel in heavily traveled ship routes such as the Panama Canal Zone, Barent Sea, North Sea, and Suez Canal Zone. This study utilized an approach by modeling corrosion using shell thickness in Abaqus Quasi-Static and applying boundary conditions in the form of temperature increase up to 800°C and subsequent cooling back to the initial temperature. At the maximum temperature, the most significant mid-span displacement occurred in the circular core sandwich panel, with a value of 4 mm. The axial force in the structure was inversely proportional to the mid-span displacement. In the case of the circular core sandwich panel, the axial force was 96 kN. The most resilient core type was hexagonal because it experiences the least deformation when compared to circular and square cores.

The goal of this article is to assess the views of university students on their mobility in the context of the COVID-19 pandemic. To achieve this goal, a survey was conducted to analyze changes in student mobility patterns before and during the pandemic. The research was conducted in March 2021, during the pandemic, and for its purpose, information was collected on various aspects of student mobility, including the form of study, destination, mode of transportation, and shopping location. The sample group consisted of university students from different backgrounds, and various features, including age, gender, residence, and driver's license status, were considered. In addition, the study examined the impact of COVID-19 on student mobility. The study found that the pandemic has significantly affected student mobility, with a shift towards remote or hybrid learning and preference for cars, bicycles, and walking over public transportation in bigger towns while in smaller towns and rural areas, student mobility behavior has remained relatively unchanged.

The present study investigates the structural integrity of a wind turbine tower structure under axial compression, described as a tapered tubular structure. Initially, the NREL model of the 5 MW-net wind turbine model was adapted and then scaled down to simplify the numerical analysis and for the convenience of future experimental study. The analysis was conducted using the Finite Element Modelling software Abaqus. To ensure the validity of the FEM modelling, the benchmarking study is conducted by referring to previously published work. The case configuration was developed by varying the material properties of the tower (high, medium, and low carbon steels) and the material properties of the tower due to the effect of the site temperature. The results obtained show that high carbon steel has the best properties for use in wind turbine structures. At -80 °C, this is the temperature condition where AH32 material has the best properties.

This study addresses the complexities of shipboard desalination plants and scaling control methods in seawater distillation systems. Using advanced modeling techniques, the study examines the interaction of various parameters affecting system performance. Factors such as seawater density, thermal conductivity and specific heat capacity are considered along with scale deposition parameters such as salt concentration, scale formation rate and deposition rate. The study includes thermodynamic analysis, scale formation kinetics and heat transfer between different components of the system. The effect of salt concentration and pressure on scale deposition rate is also studied. The resulting integrated model provides insight into the optimization of desalination processes on board ships, thereby contributing to the improvement of water management strategies in offshore operations.

Safety risk management in shipping projects is an extremely important aspect aimed at ensuring the success of the project and the safety of all participants in the maritime transportation process. This paper presents an approach to assessing safety risks that considers multiple factors including equipment condition, external circumstances, and human factors. The risk assessment utilizes the probability of accidents and their consequences, as well as the weighting factors of each factor. The results of the assessment are interpreted using a scale that defines the hazard level. The proposed methodology can effectively identify, analyse and manage safety risks, which can contribute to the success and safety of shipping projects. The study also discusses the importance of dividing the crew into functional groups based on the operations performed, which helps to better identify the safety risk for each group. Safety risk assessment is conducted for each operation individually as well as for the entire project or multiple operations to provide a comprehensive safety assessment. The results of the study have shown the feasibility of the proposed method for assessing the safety risks of shipping projects and its suitability to the initial data "safety" taking into account its separate sides, features, as well as the constituent aspects of the concept, systematization of the ship's safety structure in order to develop solutions to improve integral safety and optimize decision-making in emergency situations. Achievement of the general purpose of shipping safety thus means realization of ways of reduction of influence of the human factor on the number of accidents, and an estimation of the degree of influence of a set of factors on a ship during operation. [ABSTRACT FROM AUTHOR]

The subject of this article is to model and streamline processes in the area of the transport-supply logistics in a specific enterprise. The topic of the manuscript was implemented in a particular enterprise with the residence in the city of České Budějovice (South Bohemia region). The aim of the article is to step by step analyze the current state of the supply logistics of the specific subject and propose appropriate measures contributing to optimize the entire process using selected techniques of the Operations Research. By applying the methods of multi-criteria decision analysis (such as Weighted Sum Approach and Technique for Order Preference by Similarity to Ideal Solution), the most attractive option is chosen; i.e. the optimal supplier for the implementation of the transport-supply process that will enhance the effectiveness of specific logistics activities in the operation being examined. The conclusion in detail discusses individual contributions in terms of the suggested ways of modeling and improving the current state with respect to supply processes in the selected enterprise.

The sustainability of international transport remains a critical topic of concern in both theory and practice. Ideally, scientific literature should align with practical needs, but such concurrence is not always present. This disparity is also evident in the specific issue of consignment delivery, which is currently of a great practical importance but lacks sufficient coverage in scientific literature. This paper aims to analyse current trends in maritime transport and their relevance to achieving global sustainability in international transportation. Additionally, it seeks to compare these findings with the practical needs and requirements of the industry, in order to provide constructive recommendations for further research. To accomplish this objective, a bibliometric analysis was conducted using scientific databases, including Web of Science and/or SCOPUS. [ABSTRACT FROM AUTHOR]

The share of human factor in the occurrence of navigation accidents represents a high proportion of the total accident rate. Elimination of the human factor responsible for the occurrence of navigational accidents would contribute to the overall safety of navigation on inland waterways. The main causes of human-induced navigation accidents include inattention, fatigue or poor concentration on vessel control. The design of the system for increasing navigation safety consists of a system for monitoring the life functions of a crew member as well as a position of the vessel towards the fairway / shore. The first level focuses on tracking the life function of the vessel's crew / boat master. The second level addresses the position of the vessel and the possibility of increasing safety by cooperating with the data provided by Automatic Identification System - AIS. The proposal of the system represents interconnection of both levels and brings high degree of control of the vessel in extraordinary situations.

Informatisation of the public administration of the Slovak Republic aims to create a functional architecture of the integrated information system. This system also includes the development of Agenda information systems that provide electronic services in the most automated mode, according to the principle all at once. In the fi eld of water transport, there is currently no fully functional agenda information system. Creating an Agenda Information System (AIS) will allow multi-channel electronic access to public transport services in water transport. The complex information solution of the water transport agenda will be digitalized for individual applications and submissions. Part of the Waterway Agenda Information System will also be the establishment of a client zone, an online tool that will provide online information for users and providers. This tool will allow personalized client notifi cations that simplify the process for all parties involved (public administration, entrepreneurs, or individuals). [ABSTRACT FROM AUTHOR]

Education and practical training of the crew members in water transport have been directed towards harmonisation within the EU. One of the basic goals of the project HINT (Harmonized Inland Navigation Transport through education and information technology) is the implementation of inland navigation simulators into the educational process. They might become an alternative way for practical training of crew members in near future. In this article we analyse the requirements for the functions and complexity of an inland navigation simulator in the educational process within the Danube region. The analysis comes from the research that was carried out by the organisations that work in Inland Water Transport (IWT) in the Danube region in October 2013. [ABSTRACT FROM AUTHOR]

The paper describes the energy consumption and GHG production comparison of three transport modes - road, rail and waterborne. The calculations are done according to the legislation in force - standard EN 16 258:2012 Methodology for calculation and declaration of energy consumption and GHG emissions of transport services (freight and passengers). The results have high informative value because they take into account energy consumption and emissions from primary and secondary consideration. The calculation is done by real fuel consumption values (road and waterborne) and by simulation of energy consumption (railway). The energy and emission coefficients from the standard EN were used for estimating the results according to the well-to-wheels and tank-to-wheels principles. [ABSTRACT FROM AUTHOR]