The operation of injection apparatus in self-ignition engines results from the design, manufacturing technology and wear and tear during operation. The technical state of the injector apparatus significantly affects the engine performance, fuel consumption, toxicity and smoke opacity of outlet gases. The most unreliable element of the injection apparatus is the injector nozzle, the quality of which depends on the quality of construction and production, operating conditions and the of the fuels used, etc. One of the design parameters of the injector nozzles, determining the technical state is the geometry of the nozzle holes. An attempt was made to optimize the selection of the dimensions and surface condition of the spray holes to significantly affect the flow properties of the injector nozzles and, consequently, to decide on the size and form of fuel dosed streams to individual cylinders of a self-ignition engine and the quality of fuel atomization. In work, a simulation model was developed, and the pressure losses and the mass fluid of the injected fuel were minimized for selected significant geometric features, taking into account the influence of operating conditions. With the use of Mathematica software, simulation optimization methods and methods based on evolutionary algorithms were elaborated.

This article presents an overview of an algorithm to facilitate action when planning search and rescue operations, taking into account actual hydro-meteorological conditions and the maneuverability of ships involved in the search.

The ship "Energy Efficiency Design Index (EEDI)" has been formulated by the IMO Marine Environment Protection Committee (MEPC) as a measure of the CO 2 emission performance of ships. The ship EEDI is calculated based on characteristics of the ship at build, incorporating parameters including ship capacity, engine power and fuel consumption. Shipping is responsible for CO 2 discharge of approximately 3.3% global emission and despite being an energy-efficient transport means, compared with other transport modes, there are opportunities for increasing energy efficiency. The EEDI requires a minimum energy efficiency level (CO 2 emissions) per capacity mile (e.g. tonne mile) for different ship type and size sectors. With the level being tightened over time, the EEDI will stimulate continued technical development of all the components influencing the energy efficiency of a ship. The paper presents an overview of EEDI calculation method for container vessels and results of experimental approach. The experimental process results through comprehensive analysis of operational data, from modern container vessel, equipped with direct main propulsion unit have been introduced. Ship operators have already been implementing energy efficiency operational measures and set goals for reducing the energy consumption of their fleet. Performance and savings are not always monitored and reported. However, it can be foreseen that such activity when is successfully promoted, reduction of CO 2 emissions can be achieved.

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The article focuses on the transport preferences of the inhabitants of a medium-sized city in the context of changing urban mobility and sustainable development. It fills the gap in the literature researching the changing communication behavior of the inhabitants of a given city. The main purpose of this article is to identify and analyze the preferred means of movement for inhabitants of a medium-sized city in Central and Eastern Europe. The research area was the city of Szczecin, Poland. The research was carried out using the following research methods: literature review, analysis of legal acts and documents, case study. The research material was collected using an anonymous questionnaire based on a proprietary survey made available to the inhabitants of the largest city of north-western Poland, Szczecin, in the GOOGLE browser in the period 17 May 2019–1 April 2021. The multiple-response contingency tables, chi-square test of independence and non-parametric U Mann–Whitney and Kruskal–Wallis tests were used for study development. The conducted scientific research showed that, when determining the relationship between the method and the destination, the respondents most often chose a car or on-foot commuting in all of the surveyed destinations. The research results increase the level of knowledge regarding residents’ needs in terms of urban mobility and the development of Szczecin’s transport system. They can be used in the rational actions of local authorities aiming to improve residents’ the quality of life in the context of the sustainable development of city transport.