The topic of the work is an overview study of the current problem associated with the complexity of navigation of river vessels and river-sea-going vessels during their passage along the Neva River in the raised spans of St. Petersburg bridges. It is noted that when passing through the raised spans of St. Petersburg bridges in the induced state, such factor as the “surface dimension” is one of the main ones. It is emphasized that large-tonnage river and river-sea-going vessels cannot pass all the bridges of St. Petersburg when they are in the induced state, but since the bridges are drawn at night during navigation period, the height restriction is no longer so strict. Unfortunately, all bridges of St. Petersburg have only one draw span, so reverse navigation is organized through their raised spans in order, firstly, to avoid divergences of vessels in the sections between the bridges and, secondly, to enable the skipper to minimize manoeuvring when choosing the optimal path of entry into the raised span of the bridge. In addition, the attention is drawn to the fact that when entering the drawbridge span, the skipper must take into account many additional factors, including, for example, local navigation features, the actual hydro-meteorological situation and the current hydrological regime of the Neva River. It is noted in the study that the boatmaster should take into account such an important circumstance as the presence of a large number of pleasure craft used for sightseeing viewing of the process of vessel movement through the raised spans of bridges. Due to the fact that boatmasters of large-tonnage river vessels and river-sea-going vessels may experience significant difficulties in the process of organizing navigation safety when moving into the raised bridge spans on the Neva River section within the boundaries of St. Petersburg; mandatory pilotage, some features of the organization of which are considered in this work, has been established. Examples of accidents related to the procedure of bridges drawing that occurred within the boundaries of St. Petersburg and had serious consequences are analyzed. The amendments proposed to be made to the “Rules of movement and mooring of vessels in the Volga-Baltic basin of the inland waterways of the Russian Federation” in relation to the issue under consideration are considered.

When solving a number of practical problems of navigation and ship maneuvering, it is necessary to take into account the effect of wind on the parameters of the ship motion, including curvilinear motion, in particular, on circulation. There is very little information on this problem, especially in terms of quantitative estimates of the wind impact on circulation elements. Based on this, the purpose of this work is to study the effect of wind on the circulation elements based on mathematical modeling and to determine quantitative estimates of this effect when changing such factors as wind speed and heading angle, ship length and rudder angle. The simulation is carried out on a certified navigation simulator Transas NT Pro-5000. The mathematical model of vessel movement and wind effect used in this simulator is presented in the paper. A description of three simulated container ships with similar aerodynamic characteristics is given for the various heading angle and velocity of the wind before the start of the turn. In some experiments, the rudder angle is changed. The results of the simulation are presented in tabular and graphical forms. Quantitative estimates of the displacement of the turning points on the circulation by 90°, 180°, 270° and 360° at wind influence from the corresponding points of circulation in the absence of wind. The graphical dependences of these displacements on the heading angle of the wind and their analytical approximations are presented. The ranges of the wind heading angles at which the maximum effect of the wind on the circulation elements is observed are established. Quantitative estimates of the inversely proportional dependence of the circulation elements on the ship length are calculated. The hypotheses of the other authors about the direction of displacement of the circulation curve under wind action are tested. To verify the validity and reliability of the results obtained, it is necessary to perform similar studies using other mathematical models and natural experiments.

The article aim is to identify mean values and change trends in the frequency of winds that pose a danger to navigation on shipping routes of the Laptev and East Siberian Seas which became evident in 2010–2021 period. In the period under review the winds were considered dangerous if their average hourly speed over the water surface at 10 m altitude exceeded 15 m/s. The factual material is based on information from the ERA5 global reanalysis. The research methodology involves the use of standard methods of mathematical statistics. A comparative analysis of the last two 12-year periods (1998–2009 and 2010–2021) has shown that the climate changes that happened in 2010–2021 significantly affected the wind regime of the studied region, which had consequences for shipping. In August, a significant decrease in the frequency of dangerous winds was recorded in the region, which generally contributed to the improvement of navigation safety by reducing storm risks. Opposite trends manifested themselves from September to December, which led to increased storm surge and a rise in the likelihood of ships icing, especially on the high-latitude paths of the Northern Sea Route and approaches to the Long Strait. The decrease in the frequency of winds, revealed in January and April, contributed to the preservation of a stable ice cover and stable difficult navigation conditions in these months. The persistence of the identified trends in interannual changes in the wind regime in the region under consideration in the future is not guaranteed. Therefore, the development of the existing network of Arctic weather stations remains an urgent problem for shipping.

The basis for designing and upgrading new sea ports and container terminals is regulatory documentation. A part of designing a new sea port is making key technological decisions, including on calculating its cargo throughput capacity. However a method for capacity evaluation of operating ports is not described in the regulatory documents. Operating cargo terminals often undergo significant changes since the moment they were put into operation. Equipment, resources and infrastructure of cargo fronts should not be the only thing taken into consideration when evaluating an existing container terminal capacity. The way in which a terminal interacts with external transport systems (railroad, vessel fleet, etc.) as well as interactions between cargo fronts inside a terminal should also be considered. A discrete-event simulation model for the system consisting of a railroad cargo front, a container yard and a berth cargo front of a container terminal is proposed in the paper. This model allows to evaluate the balance between calls of different modes of transport (vessel calls, cargo train calls), as well as the impact of this balance on the state of container yard and on the terminal cargo throughput capacity in general. Container terminal in terms of proposed model is not merely a set of unrelated objects, but a system. In such system interaction with one of elements has influence on all the others. The model is described as mathematical dependencies between key variables. Cargo train and vessel calls generation is performed via standard spreadsheet methods. To acquire more accurate results, specific sea port statistical data should be used.

Due to the new concept of the country transport logistics development “Turning to the East”, it is becoming the more important to increase the processing capacity of container terminals in the Far East. This research work is to study the possibilities of increasing the throughput capacity of container terminal areas by making the technical and technological management decisions. The opportunity of introducing automation elements into the terminal operation through the creation of a technological cyclic automatic machine on the basis of mobile container transporters is investigated as an idea to increase the processing capacity of the terminal equipment. In the context of developing the concept of the loader operation as a technological machine, the “working cycle” term is defined as a sequence of actions during performing the technological operation of picking up the target container from the stack, and then the transition diagram of the machine is an analogue of the technological scheme of this operation. Based on the foregoing, the purpose of the study is defined as the rationale for choosing a unified scheme for the technological operation of dismantling the container stack as part of automating the working cycle of a loader. To achieve this purpose, the following tasks are solved: the technical capabilities of loaders such as a reach stacker and a loader with an upper grip spreader are studied when working with a stack depending on the location of the target container in the latter; technological schemes for the execution of the operation of picking up target containers from a stack, differing in the type of equipment used and the method of disbanding blocking stacks, are considered; the positive and negative aspects of using each of the technological schemes as an analogue of the transition diagram of the technological machine control unit are revealed. The result of the research work is the technological scheme “the use of a reach stacker or a loader with a top grip spreader with complete disassembly of blocking stacks and picking up containers only from the near row”, which is the most preferable in terms of such important indicators for automating the technological process as versatility, “trouble-free” execution technology, insensitivity to stack capacity.

The problem of vulnerability and local incapacity of global satellite navigation systems is formulated. The expediency of alternative positioning methods to create a precedent for high-precision location determination in the satellitedenied environment is revealed. The hypothesis about the impossibility of a separate alternative to meet the requirements of full autonomy of modern navigation when it is necessary to comprehensively solve geolocation scenarios based on the combinatorics of various technologies is put forward. An assumption about the probable advantage of combining data from several information sources to compensate for the disadvantages of each option when predicting an increase in the overall reliability and accuracy of navigation parameters is made. An opportunistic navigation paradigm with the objective function of obtaining location information from mixing additional radio frequency signals with simultaneous visualization of a spline positioning map to determine the location inside a graphic fragment is proposed. The confidence that the approach from the standpoint of spline functions expands the horizon of possibilities of the concept of opportunistic navigation from the purely technical synergetics of the landscape of «signals of opportunity» to the creation of a perspective positioning system using effective electronic mapping is expressed. It is determined that the positioning accuracy of navigation systems is practically necessary to build an optimal trajectory for the safe routing of the vessel. Attention is focused on understanding the optimality of the trajectory as a multi-way planning strategy within the framework of the «receding horizon» paradigm with the obligatory condition that a waypoint with a user-defined probability is achievable by a moving object. It is noted that the modeling of optimal trajectories is implemented by a method similar to the technology of interpolation of navigation contours based on the composition of a B-spline with the provision of an attribute parameter to maintain the same value at each point as a result of the analysis of the spatial anisotropy of the source data. The synthesis of threedimensional spreading of magnetic map anomalies has been tested to create a mapping standard based on a hybrid approximation algorithm as an implementation of a method for computer rendering a geometric primitive of a function of two variables. The postulate of increasing the potential of high-precision localization of the position of any mobile object in space is interpreted, provided that the ontology of opportunistic navigation is applied in practice as the realization of situational awareness of interdependent technical systems in order to maximize the reliability of observation.

The use of laser equipment is one of the promising ways to create innovative and highly efficient technologies in the production of ship structures. The main advantages of using laser technologies in the production of marine equipment are increased productivity by increasing the speed and reducing the number of welding passes, improving the quality of welded joints due to the accuracy of the assembly of structures and the level of automation, reducing the level of residual stresses, warping and leash due to significant localization of the heating and penetration zone compared with arc welding technologies, a significant reduction in the consumption of welding materials or their complete exclusion due to the smaller dimensions of the geometry of the cutting edges and the width of the assembly gaps. The mechanical properties of the welded joint are determined by the composition of the steel and its structure. The structural-phase transformations of the weld metal are determined by the temperature-time parameters that occur in the seam zone itself and in the heat-affected zone. Laser welded joints are formed under conditions in which thermal cycles differ significantly in depth and width of the weld, so the mechanical properties of the joint are determined by local changes in the structure of the seam metal and heat-affected zone. The issues of formation of the phase composition of the seam zone and heat-affected zone during laser welding are examined in the paper. On the basis of numerical modeling of thermal processes and structural-phase transformations of weld metal and heat-affected zone accompanying laser welding, a method for quantifying the volume fraction of structural-phase components of weld metal and heat-affected zone is proposed. The proposed calculation algorithm avoids solving the equation for the amount of the volume fraction of the structural-phase components of the metal at each step of the calculations.

The implementation of federal programs for the modernization of the transport system of the Russian Federation requires the solution of a set of tasks, the most important of which is the training of highly qualified specialists in the transport industry. A necessary condition for high-quality training of specialists is certainly a modern educational and laboratory base. The Admiral Makarov State University of Maritime and Inland Shipping has been training specialists in the field of marine energy for many decades. In order to continue training specialists in this area at a high level, it is necessary to modernize the material base, create laboratories that meet modern requirements. In order to achieve this goal, a project to create an educational and scientific center “Energy efficiency and reliability of marine machinery and mechanisms” is proposed. The concept of creating a center is presented in the paper, the laboratories that should be part of it are listed, the examples of laboratory layouts and their main equipment are provided. It is proposed to include a laboratory for testing engines in container design and a floating laboratory in the educational and scientific center. The creation of an educational and scientific center equipped with modern equipment will provide conditions for high-quality training of specialists for industry enterprises, as well as provide an opportunity to solve current scientific problems in the field of marine energy. The concept of creating an educational and scientific center is supported by the Board of Trustees of the University

The development of modern energy is inextricably linked with the further improvement of heat engines, which are still the only primary sources of mechanical energy on an industrial scale. Given the existing environmental problems, Stirling engines can be a good alternative to internal combustion engines and turbines. Of the many problems of creating such a sufficiently powerful and economical engine, it is customary to consider three main ones: 1) efficient transfer of large heat fluxes in the heater, regenerator and refrigerator; 2) creation of reliable and durable seals to hold the working fluid in the cylinder; 3) ensuring minimal friction in bearings and seals. And yet, of the three listed problems, the first should be given more attention, first of all, due to the unique conditions associated with the continuously changing thermo and mechanical loads. The instability of the loads is further complicated by the sharply different heat transfer coefficient on the external and internal heat transfer surfaces. That is, there are factors that contradict the requirements for the size of the heat transfer surface, the friction resistance of the working medium and the dead volume of the engine as a whole. In this regard, it is of interest to search for possible ways to reduce the effect of negative factors of non-stationary heat transfer in the calculation of heat exchangers. The current lack of suitable theoretical methods of calculation forces the use of semi-empirical methods. The aim of the paper is to assess the significance of the unique, characteristic of Stirling engines, the negative phenomenon of the delay in the flow of the working fluid in heat exchangers. For this purpose, a real kinematic diagram of the movement of the engine pistons with a rhombic drive by R. Meyer, created using the design program, is used. The analogue is the 4–235 type real engine of the Philips Company. In the calculations, a step-by-step procedure for calculating the time-varying parameters of the working fluid is used. The need for such a solution is due to the fact that in the rhombic drive of R. Meyer, the pistons movement and the change in the displaced volumes complexly depend on the angle of rotation of the engine shaft. In addition, the exact value of the real change in volume is possible only when the terms of the analytic equation of volume change under consideration are decomposed into a Fourier series.

The content of operation as one of the most important stages of the life cycle of a technical system is revealed. The structure of the process of technical operation of electrical engineering systems is considered. The essence of the individual stages of operation is revealed, their functional purpose is given. It is shown that some fundamental concepts related to operation do not have an unambiguous interpretation. The well-known definitions of these concepts are considered and a one-digit formulation of each of them, which corresponds to the current standards, is given. Special attention is paid to the disclosure of the content of the concept of state and consideration of various types of technical states of the system. The definition of the “condition” category, the formulation of which differs from the known definitions and allows more fully and accurately solving the problems of diagnosing the studied electrical systems, is given. An important feature of this definition is that it fixes the continuous variability of the state of any system in a function of time. At the same time, stable technical conditions that differ significantly from each other and correspond to the current version of the standard are distinguished. Such states are serviceable, faulty, operable, inoperable, partially inoperable, marginal. Functional conditions that are determined by the operating modes of the system are considered. The current definitions of the most important properties and events, among which a special place is occupied by reliability, survivability, safety, failure, damage, defect, are given. For the selected technical states, a model in the form of an oriented graph is synthesized. It is shown that the actual process of an electrical system operation has two features. The first one is that the probability of transition from one state to another does not depend on the type of state the system is in at the moment. The second feature is that the time spent in each technical condition can be either deterministic or random. The conclusion about the possibility of modeling the process of changing the technical states of the system by semi- Markov models with a discrete set of states is made. A mathematical model in the form of Kolmogorov differential equations, which makes it possible to estimate the probabilities of the system being in a particular state, has been compiled.

The elements of the algorithm for designing vessels for underwater technical work such as formation of the power station of the designed vessel are considered in the paper. These are formation of the power station of the designed vessel, selection and installation of crane and diving equipment, hardware intended for use on a vessel of manned submersibles and determining the dimensions of mobile operation equipment intended for future installation on a vessel being designed to perform appropriate technological operations on the sea shelf, based on the data of a group of the same type vessels. The algorithm is intended for definition of the main dimensions of the designed vessel, namely, a number of the installed diesel generators and ratios of total power of the power station with a width, loading capacity of the crane and power of a propulsive complex of the designed vessel. Systematization of the used crane equipment as for performance of cargo and underwater and technical works, and for hardware service is performed. Systematization of a diving complex, hardware and the manned submersibles assumed to use on the vessel is also performed. The relation between the dimensions of the main deck and ship structures necessary for the installation of mobile technological equipment and complexes using databases of the same type of vessels is systematized. Using the existing design experience and a database of ships of similar purpose, a formula that allows, as a first approximation, to estimate the sizes of the power plant, load-lifting devices and diving equipment planned for installation on the designed vessel that provides service to submersibles of any type has been compiled.

Ensuring the stability of the technical systems functioning, including those in water transport, is an important area for the application of mathematical methods, including probabilistic and mathematical-statistical methods. The stochastic nature of disturbances affecting complex systems and worsening the level of stability of the latter should be reflected in the implemented human-machine control loops. One of the directions here is the accounting and use of (usually competing) expert assessments, on the one hand, and a reasonable definition of stability indicators, a choice from a variety of possibilities, on the other hand. From a general point of view of management theory, the method of using expert assessments developed in the paper can be considered as an integral part of the risk management problem that is being developed so far, mainly for economic systems and using only financial criteria. The concept of the minimum allowable efficiency of a technical system is introduced in the paper. On its basis, an approach in which the indicator of the stability of a technical system is linked to a system-wide criterion indicator of the quality of its functioning is implemented. The corresponding mathematical model as a problem of mathematical programming is formulated. Approaches to its solution including for the nonconvex multiextremal case are discussed. A feature of the proposed approach to the definition of the integral indicator of the stability of the dynamics of a technical system is the use of expert assessments in determining the probable range of changes in the controlled variables of the optimization model, implemented as a mathematical programming problem, which logically leads to the use of fuzzy set theory. With the non-linearity of the objective functions and restrictions that arise in this case, the gradient method of searching for a conditional optimum is effective.

Timely implementation of maintenance processes provides confidence in maintaining performance and integrity throughout the life cycle of the system. Various developments in monitoring and analysis methods are aimed at maintaining the operability of systems by minimizing the failure rate. The developed computer program, presented in the paper, is used as one of the tools for assessing the technical condition of a ship power plant, allowing the use of an integrated approach to predicting and managing the quality of maintenance, including an assessment of the costs and timing of the implementation of repair work. When describing the creation of a computer program for assessing the structural integrity of ship engine elements, special attention is paid to the libraries used and the methods necessary for a comprehensive consideration of the “oil-engine” system. The Makava program, based on laboratory analyzes, allows you to determine the residual life of engine oil according to the actual state, by determining the parameters that mainly affect its aging, wherein setting threshold values for these parameters, forms the degree of deviation of actual values from the boundary values, predicting further wear of certain elements of the system. The program contains a database of typical changes in oil indicators regarding the occurrence of possible structural defects in the elements of the system, helps to expand the information resource by collecting, processing, accumulating and storing information on the degradation of the components of the propulsion complex of various engine models for subsequent planning of measures for the quality of maintenance and repair of shipboard power installations.