A seabed relief-based vessel position fixing model on the basis of a four-layered feedforward neural network is proposed. Hidden neurons have hyperbolic tangent activation functions. The model is constructed for 1-D case that can be considered as vessel motion throw a narrow channel or alongside fairway axis. A sequence of spot soundings is given for the network input. The linear coordinate registered for the last sounding forms the network output. The training set is formed by means of the intentional pseudorandom alteration of input samples in accordance with suspected limits of sea level variations and the constant error of its measurements. The validation set is not used. The Adamax algorithm is implemented for the neural network training. The maximum of absolute value of the prediction error is used as a performance criterion of the net. Modeling has been conducted with the Python programming language. The Tensorflow library is used for the creation, training and testing of the neural network. The depth is modelled as a piecewise polynomial function of the coordinate. The results of neural network testing with the use of noised input samples let to state that the neural net can determine a ship position by means of soundings with acceptable accuracy. Different combinations of the sea level error and the number of hidden neurons have been considered. For each of such combinations the network accuracy indicators have been calculated. The best results are obtained for the network with 100 hidden neurons per each layer.

The problem of safe ship’s route planning at the variable hydrometeorological situation along the route is considered in the paper. The problem solved in the paper is based on the division of the water area into separate clusters, depending on its characteristics. The route from Busan Port to Kushiro Port is used as an example. The specifics of this route is that it runs through the open sea, and through the straits and archipelagos. The aim of the work is to automate the process of planning the route and adjusting it during the trip, depending on changes in external conditions. The graph theory for modeling a route is proposed in this paper. The construction of graphs is implemented using the cluster analysis method. In the analysis, the water area of the route is divided into separate subareas, depending on the distance to the coast and the depths difference. Open water areas are separated into larger clusters. Near the coast and at shallow depths, clustering is shorter. The cluster centroids are the vertices of the graphs of the future route. As result it is a simulation of graphs of different sizes. The union of graphs forms the hypergraph. The distance is used as the weight of the graph edges. To determine the most preferable route in criteria of speed, cost or safety, weights are added depending on weather and other factors. As a result of this approach, several routes are planning on the hypergraph. Depending on the weight of the priority criteria, a route is selected automatically. The proposed method can be used to create systems for automated planning of optimal routes, taking into account the selected criteria under changing environmental conditions in the process of voyage and replanning it if necessary.

The current state and issues of bathymetric investigations of the East Siberian Sea are examined in this study. The main sources of bathymetric data are characterized. The possibilities to solve these issues in order to improve the efficiency of the oncoming bathymetric investigation in the East Siberian Sea for supporting the urgent practical tasks of the Russian Federation concerning the Northern Sea high latitude routes are discussed. The importance of a new hydrographic investigation through the high latitude routes in the East Siberian Sea in order to provide the possibility of year-round navigation of the large-tonnage Arc7‑class icebreaking LNG carriers is especially emphasized. Compiling of the new coastal electronic navigation charts for the new Northern Sea high latitude routes is stated as one of the main priorities. The lack of coastal electronic navigation charts of the high latitude routes in the East Siberian Sea will present a challenge for the establishing of year-round navigation for high ice-capable Arc7‑class LNG carriers during the coming several years. The drafting of high latitude routes must also consider the seafloor gas venting in the East Siberian Sea. The satellite remote sensing data from passive microwave radiometers and optical sensors using «modis & amsr2» technology provided by the University of Bremen ensures the complementary observations of sea ice concentration in the eastern part of the East Siberian Sea. The re-analysis of data from microwave radiometers AMSR‑2 beginning from 2018 provides the conclusion about the autumn degradation of the Aion ice massif. The analysis of the sea-ice concentration of the Aion ice massif during autumn–winter of 2022, the most severe in the last 5 years, allows us to give a recommendation concerning the new high latitude route in the East Siberian Sea. This route passes along the northern coast of Vrangel island into the Chukchi Sea and it is more efficient for large-tonnage Arc7‑class icebreaking LNG carriers ensuring year-round navigation in the East Siberian Sea. It is stated that hydrographic investigations carried out on the sections of the Northern Sea Route must adhere to the requirements of the International Hydrographic Organization. The urgency of developing the state integrated bathymetric database for the Arctic Ocean including the Arctic Seas data along with the necessity of providing all Russian bathymetric data acquired in the Arctic region to the assigned national centre is discussed. The FKU 280 ZKP VMF is proposed as such national centre. The importance of coastal electronic navigation charts for the high latitude routes in the East Siberian Sea created on the basis of modern technology is emphasized.

The retrospective and modern schemes for geographic and transport zoning of the Arctic and the Northern Sea Route are examined. The historical research method, which consists in identifying and analyzing documented facts, historical processes and their logic in terms of clarifying development, is used. There are several stages in the formation of zones and areas in the waters of the Arctic seas. The time period chosen for the review is from the beginning of the 19th century to the present in chronological order. International relations, national legal and natural conditions, and country characteristics are taken into account. The evolution of the organizational structure for managing the operation of the transport system of the Northern Sea Route, from the creation of the first administration to the present day, is considered. The countries of the Arctic Council have not yet developed a uniform approach to such tasks as the classification of ice (ice conditions) and requirements for the design of a vessel (ship ice class). Most countries use the definitions from the Polar Code. Individual countries apply their own rules and classification. The Russian Federation, for example, when choosing criteria for the admission of ships, uses both the national classification (Arc4-Arc9) and the Baltic one (Ice1-Ice3), while recognizing the ice classes of ships according to the International Association of Classification Societies. The results of a comparison of the Arctic Council countries on the presence of signs for development of transport-geographical zoning and navigation management in the Polar waters are presented. In conclusion, a list of tasks, the solution of which will contribute to the future transition from geographical to transport zoning of the Northern Sea Route and the Polar waters as a whole, is provided.

Over the past 20 years, in Russia the growth of small-sized fleet, which is self-propelled watercraft with a length of 2 to 24 m, intended for sports, recreation, sailing trips and cruises, is noted. The increase in the number of vessels, in turn, contributes to the construction and commissioning of small-sized fleet anchorages. The approved terminology relating to yacht infrastructure is considered and its problems are discussed. A generalized diagram of the yacht port composition is proposed. The object of this study is water transport, in particular the location of small-sized fleet. The purpose of this study is to identify and formulate problems that may be encountered during the inspection and operation of hydraulic structures containing floating pontoons intended for mooring small-sized fleets using the example of a specific yacht port. The use of the principles embedded in ESG technology as one of the ways aimed at harmonizing regulations in the creation and operation of yacht marinas is proposed. As part of the ongoing survey of the yacht port, the berth structures of the yacht port were decomposed element by element and workable and limiting indicators of the pontoon berths elements condition were proposed in tabular form. These indicators are not exhaustive and must be adjusted for the specific object of inspection, taking into account the requirements of the Customer, regulations and the design of the hydraulic structure. In conclusion, a number of questions for further research are formulated. It is concluded that an adequate assessment of the technical condition of floating berths based on the results of a visual inspection is possible with the proper organization of an expert service in combination with continuous deformation monitoring and timely repairs carried out by the operating organization.

The water transport operation, its safety and the organization of the fleet on inland waterways are presented in the paper. The problem of protecting water bodies from pollution by oil products, which are contained in the ship's bottom water (NW) formed during the operation of inland navigation vessels is considered. The results of studying this problem by the authors of the paper, based on the experience of solving this problem in the field of ships operation on the inland waterways, have shown that the most expedient, and often the only possible, way to solve it is an off-vessel treatment strategy, which involves organizing the treatment of bottom-bed water using technical means, which include in general specialized floating facilities providing reception of bilge water from operating vessels, transportation and treatment. The main principles for the offshore cleaning strategy implementation are formulated. In accordance with this strategy it is proposed to consider offshore cleaning as a certain technology, the content of individual operations of which, as well as the composition of the complex of technical means that ensure the implementation of its various options, is determined by the conditions for organizing off-board cleaning on the considered sections of the waterways, which include the need to ensure safety, requirements for the disposal of treated bilge water, as well as economic efficiency. It is shown that under certain conditions it is expedient to carry out separate operations for water purification using different technical means. The main options for the composition of the complex of technical means, including autonomous floating treatment facilities, are proposed. It has been shown that the possibility of choosing the composition of technical means makes it possible to take into account the operating conditions of ships, as well as the organization of off-board cleaning, which provides an effective solution to the problem of ensuring the safety of navigation.

The results of work to strengthen the soil foundation of the chamber of lock № 5 of the Volga-Don Shipping Canal, carried out in 2016–2017, are analyzed. The need to carry out work to strengthen the soil was caused by an increase in the intensity of sedimentation of the central sections of the lock chamber, which began in 2005. To stabilize the chamber position, the technology of two-component jet grouting is implemented. This technology assumes the formation of several longitudinal soil-cement walls in the soils of the lock chamber base, which would transfer the load from the weight of the chamber to the harder clay soils of the water-resistant layer. However, as a result of the work performed, the precipitation intensity has increased. Engineering-geological, hydrological and geophysical studies conducted in 2018–2020 recorded the absence of formed soil-cement elements in the soils of the chamber base. An analysis of the soil samples characteristics taken from the chamber base has showed that a layer of soils of 10–12 m thickness is composed of loess rocks, below which water-resistant clayey rocks lie. Initially, there were several confined and non-confined aquifers in the soils of the lock base, and the creation of a hydroelectric complex and the formation of a level difference between the upper and lower pools led to the formation of a filtration flow with a significant pressure gradient at the base of the chamber. An analysis of the properties and structure of loess soils has showed their predisposition to subsidence, transition to a floating state and liquefaction with an increase in water content. Under the conditions of weak water-saturated loess soils, the supply of a cement mixture into them under significant pressure did not lead to the formation of soil-cement elements. Thus, in accordance with the current regulatory documents, the technical condition of the gateway is defined as pre-emergency, and the security level is defined as unsatisfactory. Methods for reducing the intensity of the chamber sedimentation such as cutting through the loess layer with piles, physical and chemical strengthening of soils and water protection of the massif at the base of the chamber are considered and evaluated.

Despite the high level of modern vessel engineering development, there are a number of unresolved design and technological problems, the most urgent of which is the issue of unification of the main components and assemblies of the vessel. At the same time, an important and unresolved task is to create a unified image of the ship’s reverse gear for the needs of the domestic civilian fleet and navy. The object of study is highly loaded bimetallic plain bearings, which are elements of the “heavy” marine reverse gears of a new generation. As part of the work, a hydrodynamic calculation that refines the parameters of the plain bearings of a highly loaded marine transmission at the stage of a prototype production is performed. The applicability of the State Standard ISO 7902 methodology to the products under consideration is assessed, as well as the approximation of the performance characteristics of bearings using interpolation of two variables function is performed. The rationale for the coverage angle and the location of the pockets for supplying lubrication of bearings taking into account the thermal and viscous properties of the oil is presented. Calculations of the parameters of the critical thickness of the lubricating layer, the maximum allowable specific load and the maximum allowable temperature of bearings are performed. Based on the results of the calculations, an additional assessment for the compliance of bearings with the requirements of State Standard ISO 7902 in terms of bearing capacity and stability parameters is carried out. The comparison of the obtained results with the data of the preliminary calculation performed at the stage of the technical project is given. It is revealed that when calculating dynamically loaded plain bearings, it is necessary to take into account a number of additional factors, namely the magnitude of the relative eccentricity and relative clearance. The risks of bearings failure in the process of dynamic loading are determined. The result of the work is the correction of the geometric parameters of the plain bearings of the marine reverse gear unit in order to increase its reliability and the overhaul interval.

At present, reliability indicators are of great importance at the design stages, during operation and in cases of extending the technical life. This is one of the reasons for choosing the research topic on the application of structural methods for evaluating the reliability of ship mechanical systems. The operational stage of the life cycle of ship’s mechanical systems is considered in the paper. Durability criteria such as service life, operating time, frequency of repairs are chosen as reliability indicators. In turn, work on the repair, maintenance or replacement of ship’s mechanical systems elements is carried out in accordance with the assigned regulations or in the case of an unforeseen failure. The comparison of event models of changes in the operating conditions of ship’s mechanical systems is carried out. To estimate the remaining resource in the form of graphs, events are shown by service life and operating hours, distributed by years. In order to improve the existing methods for assessing reliability, a set of elements of the average values of the residual resource and residual output is considered. The approach proposed by the authors for assessing both element by element and the entire ship mechanical system as a whole allows us to consider the residual resource from the moment of monitoring its technical condition to the transition to the limit state, to plan technical measures and prevent possible malfunctions. Three different time slices models corresponding to planned repairs and maintenance of systems, replacement of system elements and unforeseen accidents are considered in the study. The difference in the amplitudes of the calculated indicators of the ship’s mechanical systems reliability has shown that the closer the options between the maximum and minimum values are to the average, the more accurately the statistical indicators characterize this pattern. However, amplitude deviations can be used to apply fault risk assessment. This line of research seems to be important for ships in the Arctic navigation area, which are characterized by increased requirements for ship survivability.

The subject of this study is systems for ensuring environmental safety of marine internal combustion engines, in particular, technologies for limiting emissions of nitrogen oxides (NOx). The regulatory requirements for reducing emissions are presented in the paper. The main theoretical aspects of the problem of nitrogen oxides formation during combustion in a diesel engine are considered. On the basis of these theoretical aspects the effectiveness of using various methods to achieve the requirements for the permissible level of NOx concentration in the exhaust gases is assessed. Exhaust gas recirculation (EGR) systems and selective catalytic reduction (SCR) systems are considered as the main technologies; they allow achieving the highest indicators of nitrogen oxide emissions control in accordance with the requirements of the Tier 3 standard. Taking into account the peculiarities of the requirements for the design and layout of systems as part of a ship power plant, as well as operational and investment costs, the main attention in the work is paid to systems of indirect influence on the engine in-cylinder processes, which include exhaust gas recirculation systems. Based on the comparison of high and low pressure EGR, the advantages and disadvantages of the designs are determined. It is noted that high-pressure exhaust gas recirculation systems have a number of advantages, which primarily include the compactness and high speed of the system response to changes in operational conditions. On the example of the leading manufacturers developments, the potential capabilities of the high-pressure EGR system and the engine characteristics confirming the effectiveness of its use are demonstrated. Based on the results of the work, a conclusion about the high efficiency and expediency of using exhaust gas recirculation systems to meet the requirements of the current environmental safety standards of ship power plants is made.

Studying the coefficients of kinetic energy losses of the nozzle diaphragm and the runner in an inflow turbine with partial blading of the runner is carried out. It is noted that inflow low-consumption turbines are reliable and productive devices designed to drive various units. Due to their compact size, they are especially in demand in various branches of mechanical engineering. However, in order to increase efficiency and reduce production costs, it is necessary to constantly improve the technology of manufacturing turbine stages. Some inflow turbines are partial, which leads to additional energy losses. Partial stages in which there are no losses from ventilation, namely, turbines with partial flapping of the runner are considered. To simulate such turbines, the ANSYS CFX software package is used in the work. By using ANSYS Design Modeler to create a geometric model and determine boundary conditions, as well as selecting the appropriate grid, the dependences of the loss coefficients in the nozzle and the runner are obtained. The study has shown that the degree of partiality and the Mach number of the turbine stage have a significant impact on the losses coefficients in the exact part of the nozzle and the runner. To account for these dependencies in the modeling process, empirical dependencies, which are an integral part of the design process of inflow turbines, are obtained. The use of the obtained empirical dependences makes it possible to more accurately predict the characteristics and performance of turbines of this type, as well as to supplement the existing mathematical model of the flow in the flow part of a low-consumption inflow turbine with partial blading of the runner.

The topic of the research is the development of automated control systems for real processes, which must satisfy various requirements, for example, resistance to unmodeled dynamics (robust stability), as well as meet the required quality of transient processes that arise in the case of external disturbances of various natures. In this regard, there is a need to create appropriate mathematical models for the control of non-stationary objects, the model of which includes uncertain parameters. The problem of developing and studying a mathematical model for controlling the process of electrodynamic magnetic levitation, the main problem of which is dynamic stability, is considered. It is noted that systems using the effect of magnetic levitation are widely used, for example, in shipbuilding, in elements of ship mechanisms, instrument making, as well as in the transportation of various cargoes. The relevance of the work related to the need to develop such automatic control systems that can suppress the emerging oscillatory motion of levitating bodies is substantiated. The initial mathematical model of the magnetic levitation control process, which has uncertain coefficients in differential equations and is nonlinear, is considered. To “hang” at a given (working) point of a levitating body, it is enough to create a mathematical control model in the vicinity of this point based on the linearization of the original mathematical model. A PID-based controller and feedback are added to the resulting model. The four controller coefficients are adjusted using special algorithms, taking into account the requirements for the robustness of the control system. Numerical experiments are carried out to analyze the behavior of the control system depending on the magnitude of the parameter uncertainty. Based on the analysis performed, a conclusion about the robustness of the developed control system for the object under consideration is made. The results of the study are presented in graphical form. The MATLAB system is used as a toolkit.

An approach to the problem of collision avoidance of two unmanned vessels in certain area based on cost function minimization is presented in the paper. A script written in the MATLAB computational environment that calculates the optimal maneuver to prevent a collision is described. The cost function in this study is defined as the square of the difference between the safe distance and the Closest Point of Approach, and in order to find the optimal maneuver, it needs to be minimized, for which the fmincon (a MATLAB optimization function) is used in this code. The calculation of collision avoidance maneuvers is made “ from the perspective” of the VTS: it’s optimized for two vessels and allows the vessels to pass each other at a specified distance. The script, taking as input a matrix with data on pairs of approaching vessels (their x and y coordinates, speeds, and courses), by minimizing the cost function, calculates the optimal change in speeds and/or courses for two vessels, allowing them to pass each other at a safe distance. To verify the functionality of the script, a successful simulation is carried out in MATLAB. Several examples of its operation are given. These are situations where the closest point of approach (CPA) is grea-ter than safe one; situations where the CPA is less than safe distance, but the time to CPA is greater than safe time; and situations of dangerous convergence. The calculation results are illustrated with MATLAB graphs. The code of the script described in this paper can be further refined to work in conjunction with other algorithms, and it can also be used to create training datasets for training neural networks to predict safe maneuvers to prevent collisions of unmanned vessels at sea. In this study, the influence of wind and current is not considered, and the COLREGs‑72 is not also taken in consideration. Vessels can maneuver both to port and starboard, as well as reduce speed regardless of the type of approach situation.

The purpose of the study is to determine the optimal period for monitoring calculations in complex software complexes of automated control systems. To achieve this goal, it is necessary to solve such problems as the analysis of periodic control systems, which boils down to determining the performance costs of computing systems for control, as well as ensuring a minimum of these costs. Theoretical foundations and descriptions of the process of evaluating the effectiveness of the automated control systems functioning are given. A rationale for the method of determining the optimal period for monitoring calculations in software complexes of the automated control systems is provided in the paper. An analytical study of control systems is carried out. The difference between the considered problem setting and the existing ones lies in the fact that the accuracy of error detection by the periodic control system is taken into account, while it is taken into account that for real control systems the probability of error detection is quite high. Thus, the results of studying the operational periodic control systems have shown that the main parameters that affect the optimal period of control are the mean time between failures. The dependence of the optimal control period on the probability of recovery is shown for different values of the duration of recovery by a reliable method. As the probability decreases, the optimal control period also decreases, which is associated with the need to spend a large proportion of the time on restoration using a reliable method; the corresponding increase in average unit costs can be compensated by an increase in the frequency of control procedures, i. e. a decrease in the control period. The dependence of the minimum average unit cost of control and the optimal period of its implementation on the average time between the errors appearance is given. With constant durations of control and recovery procedures and constant error detection probability, the optimal control period decreases, and the minimum average unit cost increases somewhat with a decrease in the average time between failures. This can be explained as follows: the more often an error can occur, the more often you need to control in order to reduce the losses due to working with the error.

Failures and breakdowns of marine equipment that occur during the daily operation of ships can lead to major accidents, endangering the lives of the crew and passengers of ships, and also pose a threat to the environment. A project for using a ship information system to monitor the technical condition of ship power equipment in real time through integration with ship automated systems is presented in the paper. The implementation of the information system was carried out on the Handy Size dry-cargo vessel with a deadweight of 36,987 tons, during which an analysis of ship systems was carried out and sources for obtaining initial information were identified. These were AMS system (alarm monitoring system), technical control system of MAN 5S50ME-B “CoCoS” main engine condition, equipment on the navigation bridge (AIS, GPS, ECDIS, VDR). During the implementation of the project, a secure connection to the above-mentioned ship systems for collecting and processing information using the installed Dataloger computer with software was made. Channels for transmitting information to the shore through the satellite Internet and mobile communication systems using data coding and compression to reduce traffic volume were determined. The use of the implemented information system makes it possible to remove some of the routine tasks for the crew and the onshore technical service, to obtain more accurate information on the formation and control of maintenance tasks in real time.

The purpose of the work is to increase the information content of ship control systems through the use of dynamic observers, which are, in essence, mathematical information sensors and allow you to fully restore the vector of state variables of the object model with high accuracy by measuring the output vector of a smaller dimension. An algorithm for the synthesis of observers based on the modal method of parametric evaluation of their model is proposed. It provides obtaining the parameters of the regulator according to the given spectra of the matrices of the state of the observed system and the object by means of the Control Toolbox of the MATLAB computing environment. The use of the modal method (subject to the conditions of observability and controllability) guarantees the stability of observers, which allows them to be used for stable and unstable observed objects and systems. The algorithm of modal synthesis of observers is suitable for increasing the information content of a wide range of ship dynamic systems and, above all, control systems for ship energy complexes and their components. These include autopilots, control systems for ship power plants and their elements, dynamic complexes of satellite and inertial navigation systems and positioning of moving objects in remote control conditions, monitoring and safety tools, identifiers, etc. It has been shown that in the conditions of digital transformation, the use of observers dramatically improves the quality and reduces the time for modeling the dynamics of ship systems and energy complexes operated under conditions of external disturbances, which makes it possible to improve the algorithms for estimating state variables of a class of autonomous objects modeled by nonlinear equations that allow the transition in the working area to quasi linear models with time-invariant parameters. The proposed algorithm is demonstrated by the example of the synthesis of a three-dimensional observer for the control system of a supertanker with deadweight of 150 thousand tons. The simulation of the control object is performed with an input signal of triangular shape, which most fully corresponds to the real control signal, and it is implemented in the form of a program compiled in MATLAB codes. The obtained values of state variables and errors of their recovery correspond to the specified speed and the required stability of the control system.