A vessel is a qualitatively complex movable object, which motion can easily predicted when proceeding in unchanged navigation conditions. When navigation conditions become more difficult prediction of vessel requires the implementation of a complex set of actions to assess the position and parameters of the vessel’s motion relative to the limits and directions of the waterway. Lock approaches are characterized by significantly congested conditions and variable dimensions, tortuosity of the waterway, and spatial navigational hazards of complex form, to indicate which floating and land marks are used, organized in complex patterns. Thus, the complexity of navigational and hydrographic conditions has a limiting effect on the navigator’s ability to control the vessel. As navigation conditions become more complex, the navigator changes priorities in controlling the vessel motion, gradually shifting from controlling the course of the vessel, to controlling the vessel’s speed vector, and then to controlling the motion of the stem and stern. Navigating a vessel in difficult navigational and hydrographic conditions requires periodic clarification of navigational information, for which the navigator turns to the navigational chart, which is a visual source of navigational information. Notwithstanding use of modern aids to navigation to display navigation information, such as, for example, an electronic chart navigation and information system (ECDIS), approaches to locks usually present difficulties when taking into account navigation and hydrographic factors, due to the variability of navigation conditions and the static nature of the navigation equipment system waterway. The use of ECDIS, which enables displaying 3D electronic navigation charts (ENCs) to solve the navigator’s tasks enroute lock approaches, is new. The effectiveness of their use in the process of ship handling through locks, which is significant for the navigator, is performed by modern methods in this article.

This paper considers using Monte-Carlo analysis method for evaluation some of the parameters of a container terminal. A high amount of scientific work on this topic is noted in domestic literature. International scientific literature concerning usage of Monte-Carlo method for simulating different parameters of container terminals is also analyzed. We note that foreign authors often use Monte-Carlo analysis as an auxiliary method, for example, for checking results of discrete-event simulation model of a complicated logistical system for adequacy, whereas domestic authors often use Monte-Carlo analysis as a method for direct evaluation of container or other cargo terminals parameters. This study proposes a variant of a model for evaluating the necessary container yard capacity, its area and berth utilization of a container terminal, using Monte-Carlo analysis method. We develop a model based on analytical formulas, where some initial parameters take form of probabilistic distributions, rather than determined values. Such parameters are expected cargo turnover, vessel handling equipment productivity and container dwell times. It should be noted that all these parameters can be preliminarily evaluated by port designers, investors or cargo terminal operators. We show an example of model calculations using Monte-Carlo analysis method and some values of initial parameters. Observed results are adequate for a model of such scope as it shows, for example, that most expected value of berth utilization becomes lower as the number of berths becomes larger.

The object of the study in this paper is the dunes form of transport of bed load in the channels of lowland navigable rivers. An accurate assessment of the bed load discharge is important when considering river morphology, conducting dredging and river regulation works to ensure navigational conditions, as well as when designing various engineering structures. This paper analyzes modern methods for measuring bed load discharge based on dune parameters. Considering the identified shortcomings and limitations of existing measurement methods, a new method for measuring bed load discharge is proposed. A distinguishing feature of the proposed method is the use of the average depth of the layer of moving material when determining bed load discharge. This parameter is defined as the ratio of the area of the moving material to the length of the moving material layer. Essentially, the moving material consists of dunes identified after filtering out minor bottom protrusions. The advantage of this method lies in using of the average depth of the moving material layer, which allows for all the dunes identified in the longitudinal profile to be accounted for when calculating the bed load discharge. The use of areal dune characteristics also enables the determination of bed load discharge in rivers where the bottom relief consists of deficit dunes.To confirm the effectiveness of this method, a series of experiments were conducted in the Channel Laboratory of the State Hydrological Institute in hydraulic flumes with a movable sand bed. The channel bedforms consisted of three-dimensional dunes. The flow regime in the flume was adjusted to replicate conditions typical of lowland navigable rivers. The experiments confirmed that even with the complex three-dimensional structure of the channel bedforms, the proposed method is highly accurate compared to existing methods.

The paper considers the practical implementation of the algorithm for identifying the parameters of linear mathematical models of Nomoto 1st and 2nd order of the marine vessels based on experimental data. Information from the maneuvering element tables containing information on the vessel’s circulation is used as experimental data. The initial data are presented in the form of discrete sampling, which allows obtaining the model parameters in a discrete form and then making the transition to a continuous form. The initial data are formed for each type of motion: a loaded vessel, a vessel in ballast, half-board and aboard, starboard and port aboard. The paper uses a method for determining the parameters of the transfer functions of the obtained models using the least squares method for transient characteristics. To improve the quality of the assessment of the parameters of the identified model, it is proposed to interpolate the initial data. The following methods are used in the paper: linear interpolation, interpolation by adjacent points, cubic and spline interpolation. To implement the proposed method, a program has been developed and implemented in the MatLab environment, which allows interpolation of the transient response by a method selected from the proposed ones, and then, based on the interpolated values, to determine the parameters of the transfer function. A block diagram and description of the algorithm for the operation of this program are provided. The result of its operation is a model with its own parameters for each case of vessel motion. The program displays graphs of transient processes for the initial data and calculated ones for each selected type of interpolation, and also displays the parameters of the transfer functions of the models. A description of the source data file used is provided. To assess the quality of software-implemented identification models, a model circulation trajectory is calculated and its graphic construction occurs. As a result of the program, the obtained linear mathematical models are proposed to be grouped and presented in interval form.

The article presents the results of research a prototype of a coastal software and hardware complex, which calculate optimal routes. The purpose of the article is to analyze the quality of the calculated routes depending on the effect of meteorological conditions in the navigation area. The routes plotted using the created prototype of the coastal software complex, which use information from ships and satellites allows creating and adjusting the optimal route of the vessel in the process of seaway. The analysis carried out on base of actual voyages of ships from the port of Vladivostok to the port of Magadan and Petropavlovsk-Kamchatsky. Geographic, real and meteorological (proposed by the complex) routes were compared in article. An analysis was carried out of the effect of the speed and direction of the surface wind, the speed and direction of surface sea currents and the parameters of sea waves (wave height, direction of propagation and period) on the ship’s motion. In the article, was estimated the calculated and actual speed of the vessel. The presented coastal hardware and software complex calculated meteorological models of the selected in article ships, which point to the change in their speed and course depending on the surrounding hydrometeorological conditions and ship’s parameters. The analysis result showed the inverse dependence of the effect of surface wind and sea waves on the ships speed and the direct dependence on its draft. It is give information that the change in course significantly affects the speed, slowing down it. The complex offers route options with the required track angle, compensating for the ships drift, thereby providing more favorable traffic conditions. The proposed mathematical models allow us to estimate the approximate time of the ship’s routes along alternative routes. The article shows that the complex offers route options that allow saving about 2–3 % of the total route time, which for the routes research in the article, is 2–4 hours.

The article aims to verify the hypothesis about the impact of largescale Yakutia wildfires on the ice concentration in certain parts of the Laptev Sea shipping lanes. The verification was performed using data on ice concentration monthly and daily means obtained from GLORYS12v1 reanalysis and the catalogue of Aqua and Shizuku space missions. Information on the scale and consequences of Yakutia wildfires was obtained from the remote monitoring information system of the Federal Forestry Agency. The research methodology involved the use of statistical methods, including correlation analysis. The study comprised 2001–2023 period. A significant correlation between forest burning indicators and the ice conditions in certain areas of the sea has been confirmed. The most likely cause of the identified relationship was named to be the effect of an ice cover albedo decrease due to depositing of the soot brought by southern winds from burnt forest areas, as well as earlier and warmer floods from large Siberian rivers. It has been established that in the years following periods of large-scale fires, a downward trend in ice concentration manifests itself in a number of sea areas. In the spring–summer period (May — June) they are found in the northwestern and southern parts of the sea (in the areas of formation of fast ice polynyas), which favors an earlier navigation opening. In the autumn months, due to the sea waters having consumed more heat during the summer, active ice formation begins later (October — November), contributing to its later closure. The extent to which wildfires impact changes in the ice concentration of the Laptev Sea against the backdrop of other significant factors (variations in temperature, solar insolation, wind conditions, sea level, etc.) is not straightforward and needs further research. Provided that current trends in climate change persist, it is safe to predict that in the years following periods of intense wildfires, the period of safe autonomous navigation for high ice class vessels (Arc6 and Arc7) in the Laptev Sea will be longer than normal and will comprise all months from May to December.

The topic of the paper is the study of decision-making options under uncertainty, as well as in practical situations of working with limited data in conditions of stochastic, variable influence of the external environment in the sphere of maritime passenger transportation. Attention is drawn to the fact that in this case, making a decision on modernization only on the basis of the experience of the port manager or some industry experience, on the one hand, is quite limited in the choice of alternatives, and on the other hand, may lead to incorrect decisions in the field of development forecasting, formation of measures to change the position of the marine passenger port in the sea region in relation to other terminals and evaluation of the target function of the port. It is noted that one of the tools for data collection is continuous monitoring of changes in route ferry and cruise networks and analyzing changes in the infrastructure of other passenger ports in the region. For completeness of data it is proposed to use multi-scenario modeling in the digital twin of the sea passenger port developed in AnyLogic environment, as well as to perform optimization experiments to obtain a set of values for the number of cruise and ferry vessels for the upcoming navigation. It is noted that the use of a simulation model makes it possible to include such an influence of the external environment as the trend of increasing size of cruise and ferry ships, which forms new infrastructure requirements for the creation of new or modernization of existing berths. In this case, the introduction of prioritization in the model of the incoming flow of ships is reasonably proposed. The object of the study is the incoming flow of cruise and ferry ships with prioritization in the queue. A comparative analysis of applicability of different mathematical distributions of mass service systems for incoming ship flows into the sea passenger port system with prioritization is presented. The developed simulation model is based on the available real data on the passenger port infrastructure of marine “Passenger Port of St. Petersburg ‘Sea Facade’ and ship calls for the past years. A multi-scenario random input flow of cruise and ferry ships with several priority characteristics is considered. As a result of modeling a set of data is formed, which for the port manager is a necessary field of utility and a basis for the use of decisionmaking models under uncertainty. As a result of multi-scenario simulation, the obtained throughput simulation data under different flow distributions were analyzed. Based on the performed experiments, the efficiency of using the beta distribution was determined. Based on the simulation results, the applicability boundaries for each distribution were determined and a confidence interval of maximum intensity was obtained, which can be used as a reference for making decisions on port infrastructure modernization. The methodology of data formation on the basis of multiscenario modeling allows to form the necessary set of data taking into account the influence of the external environment for decision-making on the model of marine passenger terminal development. The presented methodology can be extended to the study of systems: “sea ferry / cruise lines — sea passenger port — land infrastructure”.

Special attention is paid to the need for reasonable generalization aimed at adequately displaying the characteristic features of the seabed relief profile in accordance with the principle of navigational isosurface in electronic visualization of underwater relief. It is assumed that as a result of generalization of the bottom relief, safety contours can be extracted directly, since they represent traces of a cross-section of the profile of the underwater relief with horizontal planes. A hypothesis has been put forward on the applicability of the B-spline approximation for modeling a safety contour in order to effectively implement a practical guarantee against grounding a ship. A modification of the safety contour based on the control of the smoothness of the constructed curve in the form of bending of a serpentine B-spline structure has been tested. An analysis of the optimality of configuring B-splines on a variable type of supports is carried out with the determination of preference for the cubic case. The straightening of the safety contour focuses on local deformation while maintaining strategic descriptive characteristics. The use of the smoothing procedure on the deep side of the safety contour is justified, provided that the basis points of the synthesized curve are artificially preserved. The data of the author’s computational experiment on the accuracy of calculation by cubic B-splines with a result two orders of magnitude higher than theoretically predicted are presented. It is noted that the technologies of automated processing of bathymetric survey results do not replace the human factor, but provide the potential to unlock new cognitive capabilities of an expert in the transition from lithographic publications to digital cartographic products. The arsenal of basic piecewise approximation is interpreted as the variability of the model of an additive B-spline neural network to provide an incentive for the use of artificial intelligence to generalize contour lines of marine subjects. It is emphasized that the spline technology, by its mathematical architecture, is basically devoid of the computational problem of dimensionality, which serves as an additional factor for the use of piecewise approximation in solving complex navigation tasks.

The paper considers the issues of quantifying the indicator of the freight market conjuncture and analyzes some basic principles used in calculating freight indices. It is noted that the current geopolitical situation has a significant impact on the general behavior of the global freight market and inevitably leads to temporary restrictions on the functioning of the Russian market, which objectively determines the need to calculate domestic indices based on their own methods. The existing world practice of determining freight indices is considered, as well as the features of the Russian freight market as an integral part of the world market. It is emphasized that the nomenclature of transported goods, the geography of transportation and the parameters of the fleet used are radically different from the world ones, which makes them irrelevant for Russian shipowners mastering export cargo flows from Russia and also that foreign freight indexes are only informative and cannot be used in practical work. The paper shows the structure of the formation of freight rates and identifies the main components of the carrier’s expenses. The structure of the freight rate is the basis for the formation of the proposed methodology for calculating freight indices. The criteria for determining the specific weights of individual sectors of the freight market are considered. The conclusions drawn in the conducted research are supported by analytical data presented in graphical form. The practical use of the presented methodology will allow interested parties involved in transportation to make informed management decisions.

Materials used for manufacturing ship propellers were listed, and classification of technologies of repairing ship propellers with cavitation wear spots was cited. The characteristics of materials used in the technologies were given. The advantages and disadvantages of the repair through deposition by welding as main technology at present time were listed. Alloys most resistant to cavitation wear were considered: dispersion-hardening alloys and alloys, in which the phase transformation occurs in cavitation impacts. The low manufacturability of mentioned alloys was pointed to, that is the principal cause of the fact that these alloys did not have a wide distribution in ship propellers repair. In modern practice of deposition by welding, the filler materials close by composition to the propeller alloys are used, and priority is given to regular recovery of surface quality and not to the rise in the surface wear-resistance. Improvement of the welding technology is now directed at the development of technological methods to raise the wear resistance, that is the methods, not based on the using the filler materials different from ship propellers materials. The advantage of the use of polymeric materials to repair the cavitation wear spots on the blades is noted. All the repair compounds are made of thermosetеtting resins, the most widespread of which are epoxy compounds. The peculiarities of cavitation attack on the blade surface in service are analyzed. It was mentioned that polymeric compounds being used nowadays are developed without taking into account these peculiarities. One has to draw attention to that the longevity of polymeric compound under propeller cavitation is determined in many respects by the adhesion of polymer to propeller material. A solution for the problem of the low adhesion of the polymer compounds to the propellers alloys will displace the repair technology based on the deposition by welding in future.

The article presents the results of an experimental study of the influence of motor oil properties on the level of torsional vibrations of the propeller shaft of a Yaroslavets-type vessel. The tests were carried out on mooring lines to create the maximum load on the 3D6 main engine using standard MS20 motor oil and oil with copper additives. Torsional vibrations were measured using a certified verified strain gauge complex “Astech Electronics” (Great Britain) installed on the propeller shaft. The study found that the use of oil with copper additives and MS20 oil does not significantly affect the amplitudes of torsional vibrations of the ship’s propeller shaft in the range of crankshaft speeds of the 3D6 main engine from the minimum stable to nominal. It was found that during the startup of the main engine with oil with copper additives, the level of torsional vibrations decreases, which requires research on more powerful marine diesel engines and an assessment of this effect. When using oil with copper additives, a reduction in the overall spectrum of harmonic component amplitude oscillations is achieved, which leads to a positive effect of reducing stress in the crankshaft and gearbox. Torsional vibrations in the elements of the machine-propulsion complex of a Yaroslavets-type vessel when used as a tug do not exceed the permissible values calculated according to the RCO rules, so additional measures to reduce them are not required. Additional experimental studies are needed to assess the effect of lubricating oil with copper additives on the vibroacoustic characteristics of marine diesel engines — vibration level and external noise.

The article deals with the issues of design and construction of a laboratory stand of a ship boiler plant based on Kiturami TURBO17 boiler, located in the laboratory “Ship Boiler and Steam Generating Plants” of the Federal State Budgetary Educational Institution of Higher Education “Astrakhan State Technical University”. The laboratory stand considered in the paper, made in accordance with the requirements of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW 78), was developed for scientific research and training of students. The article presents a comparative analysis of the laboratories of higher educational institutions, graduating specialists in the specialty 26.05.06 “Operation of ship power plants”. The description of the main components of the stand including its circuit diagram is given. It is noted the importance of laboratory stands, which are close to the ship’s performance, for the training of specialists. It is emphasized that this laboratory installation allows to conduct laboratory and practical classes aimed at providing students with theoretical knowledge and practical skills. It is noted that graduates should know the basic principles of operation and design elements of ship power plants, including boiler plants and their servicing systems, as well as have theoretical knowledge of thermodynamics, hydromechanics, be able to carry out calculations in thermal cycles, heat transfer processes, heat balance. The developed laboratory test bench can be used in the study of disciplines “Ship Boiler and Steam Generating Units”, “Operation of Ship Boiler and Steam Generating Units”, “Ship Auxiliary Mechanisms, Systems and Devices”, “Automated Control Systems of Ship Power Plants”, as well as for scientific research. The project on creation of the laboratory stand can be implemented for training of specialists in other specialized universities of the country.

The article discusses the results of an experimental study of the effect of the properties of domestic engine oils with copper-based additives produced by Kupper on the vibration and noise levels of marine propulsion systems using the example of a 3D6 diesel engine. 3D6 diesels are representatives that widely cover both the transport and marine sectors of power plants, which explains their choice as an object of research. Increased noise and vibration levels on ships negatively affect crew members and passengers and lead to fatigue and distraction of the watchmen. The engine oil used was standard MS20 oil, which is used for high-speed marine diesel engines and an innovative oil with copper-based additives. Comparative measurements of vibration and noise were carried out on a Yaroslavets-class vessel using an authorized vibration and noise meter of the first class Ecophysics110A. As a result of the study, it was found that vibrations in the most vibro-active modes of operation of the 3D6 diesel engine are reduced by 30–50 % when using oil with copper-based additives. The use of oil with copper-based additives also has an effect on reducing noise in the engine room, but in the high-frequency spectrum with a frequency of more than 1000 Hz. More effectively, engine oil with copper-based additives affects the reduction of the overall noise level in the wheelhouse of the vessel and as a result, an effect of about 3 dB was achieved, which reduces the effect of noise by 1.4 times in terms of physical perception for humans.

The paper considers the problem of automating the search and construction of the shortest closed route for a group of merchant ships on a given set of transit nodes of the transport network with known coordinates. The goal is to find the shortest closed route that passes through all hosts only once and ends at the outgoing node. In general, a weighted graph can serve as a mathematical model of such a transport network, in which the criterion for the efficiency of the desired route can be, for example, the distance between cities or ports, time or operating costs. This allows you to identify time reserves that can be used to save fuel and energy, taking into account the load and cost of goods, travel costs and other factors. The work uses a combinatorial method using stochastic (probabilistic) programming, which is implemented using an annealing simulation algorithm supplemented by a recursive step-by-step optimization procedure. The problem belongs to the class of transcomputational even with a small network dimension, which makes it impossible to solve it by brute force on modern computers in a reasonable time. The proposed modification of the simulated annealing algorithm eliminates this limitation and allows not only to evaluate the shortest paths in the network, but also to build closed paths that pass through all the vertices of the network once. The use of an iterative strategy in the algorithm using a probabilistic scenario according to the Monte Carlo method allows you to avoid the solution falling into the local minimum and provides global optimization. The algorithm is implemented in MATLAB codes in the form of a recursive step-by-step optimization procedure with the construction of a curve of a closed route on the coordinate plane through the entire set of nodes of the transport network without mutual intersections of its sections. It is shown that the result of recursive optimization is to obtain a numerical estimate of the closed path of the minimum weight in the full weighted graph, which is a model of the transport network with the definition of an array of transit node numbers on this route. The developed algorithm and global optimization procedure can be used to automate the search for energy-efficient solutions in the control of robotic and unmanned objects, as well as ships in the performance of cargo transportation in water transport.