The results of experimental studies of water flow characteristics and sediment transport parameters carried out in a hydraulic flume with a sandy deformable bottom under steady and unsteady water flow conditions are considered in the paper. The experiments were carried out in the hydraulic flume 8.0 meters long and 0.21 meters width. The flume is equipped with devices for changing the bottom slope in the range of values: straight — up to 0.025, reverse — up to 0.015, as well as for automatic reproduction of the flow hydrograph according to a given program. The range of flow rates in the experiments varied in the range from 2.0 to 6.0 l/s. Quartz sand with a diameter of 0.1 to 0.3 mm was used as channel material. The intensity values of changes in the main characteristics of the river flow during the propagation of wave are determined in the work; and this intensity including the nature of changes in the level regime and slopes of the free surface, as well as the regime of water flow velocities, is evaluated. The parameters of bedload transport including the length and height of dunes, the speed of dunes movement and the sediments flow rate are studied. Statistical processing of the dunes relief parameters with steady and unsteady water movement is carried out. Hydraulic studies and numerical experiments have made it possible to identify the specifics of sediment movement in conditions of unsteady movement. It has been experimentally established that with unsteady movement of water, sediment transport is activated at the moments of the water release wave passage. At the same time, the main parameters of the sediment transport, namely, the dunes movement speed and sediment consumption, increase in comparison with the steady movement of water.

New approach for the analysis of the incoming flow of cruise or ferry ships, taking into account the division into sizes and the formation of new signs of berths “priority”, is proposed. To solve the problem of multiscenario modeling it is proposed to use Poisson and normal distributions. Also, in order to extend the model of ship requests prioritization, it is proposed to consider the situation when the intervals between ship calls in the flow of ships obey gamma distributions that take into account the after-effects of the flow. The reference data in this paper are the known intensities of operation of the Passenger Port of St. Petersburg “Sea Façade” during the navigation period. To verify the results, the data for the maximum monthly load of the sea passenger port are chosen. The performed analysis of berths loading is presented in the paper and the data on intervals between cruise and ferry ships are investigated. To solve the problem of “multiscenario modeling”, a new digital model of the sea passenger port is presented. The digital model aims at solving the problems of “sea cruise/ferry line — sea passenger port/ terminal” systems research, taking into account the possibility of dynamic change of parameters by the intensity of work. The justification of using “optimization experiment” is presented; the results of the research performance both without the “priority” parameter and taking into account the “priority”, as well as the results of the runs of the developed special digital model of the passenger port are given. On the basis of the results of multi-scenario modeling, new results, proving that the introduction of cruise or ferry ships “priority” into the model by berths achieves the effect of increasing the throughput capacity, are obtained. Based on the presented modeling, the effectiveness of including a study based on gamma distribution is confirmed. The obtained results of multiscenario modeling with the allocation and implementation of “priority” in conjunction with the use of macro-level regional planning based on Circos intensity diagrams allow us to form a complete data set for multi-criteria analysis of changes in response to the influence of the external environment and assessment of the sea passenger port position in the sea region. The presented methodology, developed models on “prioritization” and modeling results can be applied to other maritime ports.

The method for obtaining the vessel fixed position from redundant measurements of one of the main navigation parameters that is distance which is traditionally used in navigation practice in coastal navigation is being under the present research. A new approach to solving the isostages equations based on measured distances to the corresponding pairs of landmarks is reduced to solving equations of straight lines obtained from the intersection points of the corresponding pairs of isolines. These lines are similar to the position lines built along the chords. In contrast to the classical method for the position lines the proposed chord lines directly converge at the fixed position which is obtained from the isolines. The proposed method eliminates the methodological error from replacing the isolines with the position lines and the need for additional iterations. The traditional navigation methods (the theory of isolines, the generalized method for position lines, the least square method) are facilitated as a mathematical framework. The solutions of the original redundant equations for position lines along chords using the least squares method are proposed. Hence, the hypothesis of random errors in measurements and reduced versions of the chords position lines for compensating the systematic errors and assessment of the vessel fixed position by the radial error is advanced. The expressions for estimating systematic errors in measurements for the purpose of their further compensation are given. The principal points of the research are supported by the graphic interpretation, and the given expressions are adjusted to the practical application and navigation systems software development. The formalization of the proposed methods in the automatic navigation or in autonomous ship control systems will enable the navigator on board or at operating the vessel remotely to solve the problems of the navigation information processing by the pair of landmarks in coastal and congested waters on a new level.

The process of designing templates of anthropomorphic ship movement control is described in the paper. The solutions of the sequence of modeling problems are used in the state space of the ergatic “skipper-ship” system for the example of a ship of “Volga-Don” type. Parametric interval uncertainties are taken into account in the initial mathematical model of the controlled object. They influence the unambiguity of solving the optimal control problem in the classical formulation. Factors of a priori uncertainty are the draft of the ship and the depth of the ship’s passage. Numerical solutions to the problem of optimal ship movement control in terms of speed are obtained for intervals ends of the mathematical model parameters values. The solutions are used in the design of templates to describe and account for the uncertainty of the allocation of management resources according to the methodology of interaction planning in an ergatic system. The templates of anthropomorphic control in the skipper-ship system are represented by sequences of element numbers of a set of normal systems of ordinary differential equations. They are constructed in a five-dimensional space of states according to a transformed mathematical model of the ship. Each normal system of ordinary differential equations displays in mathematical form an incomplete representation of the action of virtual controls and the corresponding elementary motion of the ship due to the existence of uncertainties. The procedures for constructing various options for the allocation of anthropomorphic control resources and corresponding templates of anthropomorphic control according to expert estimates based on a variety of solutions to the optimal control problem are proposed. The constructive property of the templates of anthropomorphic control is illustrated by the specific examples. New templates can be built by joining standard templates in a certain sequence, and the standard templates themselves can be determined using information about the performed movements of the ship controls, taking into account the experience of navigation. It is shown that it is possible to use such a posteriori information to train the automatic control machine of the “skipper-ship” system by rational management methods, including those that cannot be obtained as solutions to mathematical problems of optimal control. The library of anthropomorphic control templates is presented as an integral part of the knowledge base when using the technology of expert systems in the construction of automatic control machine with artificial intelligence.

The subject of the study is the geometric characteristics of river bed forms, the knowledge of which is important for solving a number of river hydraulics problems, in particular for determining the hydraulic resistance of the channel. It should be noted that many researchers consider that its value depends on the steepness of the river dunes. At the same time, there is a lot of data indicating that in addition to the dune steepness, the shape of the longitudinal relief of the bed forms, namely, the location of the crest of the dune relative to its troughs, also influences the value of hydraulic resistance. In order to take this circumstance into account, the notion of the dune asymmetry coefficient and the notion of the wetted perimeter of the dune are introduced. The application of the possibility of approximating the longitudinal profile of the dune by a triangle has allowed us to match the main elements of the triangle with the parameters of river dunes normally used in studies of the fluvial process. Since the triangle elements are connected by well-known geometric and trigonometric relations, the proposed approximation allows us to analytically derive dependences between the main parameters characterising river dunes. For clarity, the obtained relationships are presented not only in the form of formulae, but also in the form of graphs and tables. Although the task of extensive verification of the deduced relations by actual data is not set in the present paper, the obtained dependences are in good agreement with some results of statistical processing of data from field and laboratory researches given in the literature on river hydraulics, which confirms the admissibility of approximating the dune shape by a triangle and the possibility of using the deduced relationships as at least an approximate assessment of the quantitative values of the main river dune parameters.

The effectiveness of using neural networks to determine collision avoidance maneuvers between two vessels is analyzed in the paper. A brief description of the algorithm and MATLAB script that facilitates finding course alterations to prevent collisions between pairs of vessels is provided. The process of creating training data using a previously developed script, including the preliminary data processing to eliminate unrealistic scenarios of vessel approach, as well as situations where there is no risk of collision, is described. The neural networks are trained using Levenberg-Marquardt and Adam algorithms. Throughout the study, 11 neural networks with various parameters are trained. The one that allows predicting course changes for safe distance avoidance for pairs of vessels with an accuracy of 94.8 % is selected. The accuracy of the neural networks predictions in this study is defined as the number of initially dangerously approaching vessel pairs whose closest point of approach after being processed by the neural network is within 0.8 to 1.2 miles, divided by the total number of vessel pairs. The time spent on calculating avoidance maneuvers using the algorithm and the neural network is compared. It is shown that as the number of dangerously approaching vessels increases to four or more, the neural network takes five times less time to predict an avoidance maneuver than the algorithm. With an increasing number of dangerously approaching vessels, the gap in data processing time between the neural network and the algorithm widens, which confirms the appropriateness of using neural networks in processing large data sets with pairs of dangerously approaching vessels. Future research is aimed at developing an algorithm to address the challenge of calculating safe collision avoidance maneuvers for groups of vessels through pairwise analysis of collision risks.

An overview of multiple current algorithms for optimizing the routes of autonomous surface vessels is provided in the paper. One of the effective methods for route optimization is the implementation of algorithms and software based on graph theory to prevent collisions. Key algorithms include Dijkstra’s algorithm, A*, artificial potential fields, the “dynamic window” method, and the velocity obstacle method. Collision prevention using radar of the maritime autonomous navigation vessel, geometric vessel factors, genetic algorithms, neural network training is also separately discussed. While most algorithms are only considered theoretically, some works describe practical observations: neural networks using deep learning, Markov decision processes, Q-learning; developed autonomous collision avoidance system; heuristic search for optimal ship routes using the A2015 algorithm. Overall research analysis shows that many authors have made significant progress in their work, but the topic is not fully explored. Some works do not consider divergence with multiple vessels, while others do not utilize maneuvers involving speed changes. Certain works face challenges in parameter tuning for algorithm efficiency. The optimality criterion for multiple maneuvering, considering factors beyond minimizing the closest point of approach to another vessel, such as responsibility distribution for maneuver execution, is not fully developed. It is noted that all necessary conditions for creating a universal algorithm in the future already exist due to modern technologies and the research topic relevance.

The issue of using the new Instruction for defect detection of hulls of vessels for river and mixed (riversea) navigation to predict the number of measurements of hull structures during the subsequent regular survey is discussed in the paper. The electronic version of the defect detection report tables provided for in the Instruction allowing the necessary calculations to be performed is taken into account. At the moment, defect detection of a ship hull is the examination, measurement and assessment of defects in each element of the ship’s hull in order to establish method and volumes of repairs that ensure its reliable operation until the next regular survey under specified operating conditions. However, the application of the new Instruction will not allow us to measure every element of the ship’s hull, but only those elements whose measurement is necessary. An algorithm for filling out the defect detection report tables in their electronic version is provided in the paper, and the need for a preliminary (calculation) stage of defect detection, which is essentially an analogue of the concept of the zero stage in ship repair, is substantiated. The preliminary stage of defect detection is based on a probabilistic approach to predicting the residual thicknesses of individual ship’s hull elements using known wear rates and data from ship’s hull defects detection performed previously. The results of calculations of a test example for a representative vessel, for which detailed information both on the hull constructions and on the results of measurements during the previous survey and repair is available, are presented. Using the test example, it is proven that introduction of the preliminary stage of defect detection process will reduce number of measurements of hull structures by 78 % compared to the traditional approach to performing the detection work. The necessity of development at the preliminary stage not only electronic table, but illustrating maps of measurements of the main hull structures, examples of which are given, is substantiated.

The tests to determine the adhesion of epoxy compound K‑153, containing different amount of bronze powder, to aluminum bronze are carried out. As the bronze powder the filings, which are obtained by filing the rolled rod of bronze BrAZhNMts9–4–4–1, are used. The conventional size of the bronze particles amounts to 18 μm. The epoxy compositions are applied over the plates made out of BrAZhNMts9–4–4–1. The mentioned bronze is chosen as close analogue by composition to bronze BrA9Zh4N4L, used to cast ship propellers. The plates thickness is 4…5 mm, and the plates dimensions in plan are equal to approximately 50 by 100 mm. Before being coated the plates are ground with abrasive paper of different grain to obtain the arithmetical mean deviation of the surface profile equal to 0,5…0,900 μm. Coating the plates and aging the coatings are produced at temperature of 19±1ºС and ambient air relative humidity of 50±5 %. The average thickness of the coating amounts to 2,1 mm. The experiments are conducted after keeping the epoxy coating during 7 days. The tests are carried out according to the scheme, regulated by the GOST 32299–2013 “Paint materials. Pull-off test for adhesion”. According to the scheme, metallic cylinders of the 19 mm diameter are stuck to the coating; preliminarily the spots of sticking are processed with abrasive cloth and solvent. Then the circular cuts are made in the coating around each cylinder and the cylinders are pulled off under the force directed perpendicularly to the coating, and the peel strength is recorded. The addition of bronze powder into the epoxy compound does not affect the peel strength that is the precipitation of the bronze particles in the epoxy compound during its hardening does not result in the decrease in the contact area of the epoxy resin with the bronze surface. This conclusion is confirmed by the calculation estimation: the calculated thickness of the resin layer in between a bronze particle and the plate surface after the completion of resin hardening is three orders of magnitude greater than the diane resin molecule size. It means that epoxy resin viscosity is too high, and the size and the mass of the particles are too small in order for the squeezing the resin, even partial, from under the particles takes place during the slow precipitation of the particles.

It is declared that an increase in the technical, economic and environmental performance of the diesel engine can be achieved by controlling the combustion process of fuel by influencing the parameters of the fuel equipment and combustion chamber. Information about the combustion process is obtained by registering in the experiment and analyzing the indicator diagram. The purpose of the study is to assess the possibility and identify means to improve the quality of the analysis of the combustion process in the ship diesel engine by obtaining reliable characteristics of heat release during fuel combustion as a result of the analysis of indicator diagrams. It is shown that the known methods and means of obtaining heat release characteristics do not provide sufficient analysis accuracy. It is proved that the heat dissipation characteristics can be distorted as a result of an error in determining the ordinate axis on the indicator diagram corresponding to the position of the upper dead center of the piston. A technique for high-precision determination of the upper dead center position, which is determined by dividing in half the time interval between two signals corresponding to the same position of the piston during its ascending and descending motion, is proposed. A device has been developed to implement this technique. Using it in practice makes it possible, by ensuring the necessary accuracy of indicating the upper dead center position on the indicator diagram, to improve the quality of the computational and experimental determination of the heat release characteristics during fuel combustion, which, in turn, allows to provide high technical, economic and environmental performance of the diesel engine during its manufacturing and improve the quality of its diagnosis during operation.

Negative climatic changes, expressed in an increase in average annual temperatures on the planet and associated with saturation of the lower atmosphere with greenhouse gases, force measures to reduce the anthropogenic factor of influence on these processes and the development of methods and regulatory tools. Despite the fact that marine transportation due to the burning of fossil hydrocarbons accounts for less than 2.5 % of total carbon dioxide emissions, in the long term, the accumulation effect can have serious consequences. The subject of this study is the energy efficiency of ships of the modern commercial fleet. The various regulatory requirements for energy efficiency are considered in the paper and the chronology of the requirements introduction at both international and regional levels is tracked. It is noted that the developed methods of energy efficiency assessment are aimed at reducing the measure of the anthropogenic factor influence on the greenhouse effect and that energy efficiency estimates are mainly based on monitoring carbon dioxide emissions when engines run on various types of fuels. The focus in the study is on measures to reduce CO2 emissions at all stages of the ship life cycle, from design and construction to ship recycling. Among the measures to reduce emissions at the design and construction stage, the issues of optimizing the ship hull and its power plant, developing structures for working on non-traditional, carbon-neutral and carbon-free fuels, and introducing alternative energy sources into the design of a ship power plant, etc. are discussed. Among the operational measures to reduce CO2 emissions, the problems of optimizing the speed and routes of transportation, the vessel loading, and operating modes of ship equipment are considered. The problems that arise in the way of implementing technologies to achieve the requirements for ships energy efficiency are considered in the paper. Based on the analysis of various methods for reducing the measure of impact on the greenhouse effect from the global shipping industry, the conclusions on the results achieved and their effectiveness are drawn.

The purpose of the work is to ensure continuous monitoring of the characteristics and operational indicators of urban facilities and its transport infrastructure by assessing the parameters that affect not only the level of organization and automation of the processes of documenting current statistical information on consumer expenditures of the population, but also the state of production of necessary consumer goods and transport services as a whole. An algorithm for numerical estimation of the parameters of regression models of consumption functions built on the basis of statistics of socio-economic development of the region is proposed. Its significant difference from the known methods of estimation is the use of neural network technologies, which contribute to a significant expansion of the technical capabilities of modeling and increase the accuracy of calculations by obtaining recurrent estimates of the vector of the desired model coefficients. It is shown that for the considered class of problems of “fitting” the trajectories of the consumption function to statistical data, it is possible to apply neural models of generalized regression networks with simple training modes and high modeling accuracy. The use of neural network technologies provides the maximum approximation of the production function model of a given structure to the neural model to a given initial approximation with its subsequent use for estimating weight coefficients. The method application is demonstrated by estimating the parameters of the discrete-dynamic model of the consumption function according to the corresponding statistical series. Calculations are performed using the functions of the Neural Networks Toolbox of the MATLAB environment. The method is applicable for quantitative estimates of the parameters of production models with complex logical-probabilistic relationships, as well as for obtaining numerical values of target indicators and indicators for assessing the development of inland water transport by statistical series and monitoring.