Volga State University of Water Transport

This article examines the theoretical and methodological foundations of forensic crime detection in the economic sphere. While this issue is important from a practical perspective, it is also one of the least studied areas in forensic theory. This latter aspect is partly due to the insufficient development of a general theory for identifying various groups and types of crimes, the principles of which could be used as a methodological foundation for studying the detection of certain categories of crimes. The purpose of this study is to define the system, from a forensic perspective, of the cognitive activities of criminal prosecution subjects during the initiation of a criminal case. This provides grounds for defining the process of identifying economic crimes as a criminal procedural activity aimed at verifying the primary factual data available to the subject of criminal prosecution regarding the possibility of a business entity preparing or committing a crime related to its professional activities, and establishing, based on sufficient data, that the act under investigation has taken place and contains elements of a crime. Based on this research, the author concludes that the object of the theory of crime detection at the initiation stage of a criminal case, in our opinion, is the criminal-procedural research and cognitive activity of the subjects of criminal prosecution, who carry out their functions and tasks within this stage. A distinctive feature of this activity is its aim to collect and verify the reliability of primary information about a crime that has possibly been committed, is being committed, or is being prepared.

A method for selecting anchor-mooring mechanisms based on the generalized characteristics obtained as a result of calculation is proposed, in conditions of a shortage of ship equipment. The article considers electric drives of anchor-mooring mechanisms based on asynchronous electric motors and reveals that some of them do not have the ability to switch the stator winding connection scheme in the terminal box. It is proposed to connect the winch electric drive through a matching transformer in case of a mismatch between the supply voltage of the electric drive and the ship's network. A single-line diagram is given, including a ship generator with a load, a matching transformer and an electric motor of the winch drive. The operating modes of the winch electric drive are analyzed: lose/take in and park under current, and an explanation is given regarding the calculation and modeling of the winch drive power supply system. It is said that the modeling of the system was performed using a simulation model previously developed by the authors. The power ranges of generators, matching transformers and electric motors for which the simulation was performed are given. The values of the maximum voltage drop at the start of the electric drive are determined, both for the ship's network voltage and for the supply voltage of the electric motor. The dependences for the power supply system with different values of the electric motor and transformer power at different generator loads, constructed based on the results of the analysis of transient processes, are given. A generalized assessment of the obtained dependencies is given, as well as recommendations for their application when selecting the winch power and determining the required power of the matching transformer, taking into account the requirements established by the designer and the Russian Classification Society. Conclusions are made and the practical value of the work at the design stage during the modernization of anchor and mooring winches is substantiated.

Piston rings are the parts that determine not only the power, but also the efficiency of the engine. Their presence makes it possible to ensure the tightness of the combustion chamber, while they are one of the main reasons for the decrease in efficiency due to interaction with the “mirror” of the cylinder. In order to increase power while increasing efficiency, a new sealing of the cylinder piston group parts is proposed, consisting of two piston rings installed in the first bored piston groove and a structurally modified piston ring installed in the second regular piston groove. This configuration of the piston makes it possible to increase the sealing efficiency of the parts of the cylinder piston group, with the condition of reducing the contact area of the structurally modified piston ring installed in the second piston groove, by cutting an annular groove on its working surface. Minimizing the contact area makes it possible to reduce the friction force to the value of the standard piston configuration, and at best to ensure operation at lower values. The sliding friction force is determined by the product of the coefficient of friction and the reaction of the support. Since the coefficient of friction is difficult to determine in the real O-ring seal of a marine diesel engine, and the reaction of the piston ring support is a value available for measurement, it is necessary to use this value to reduce the friction force. A calculation technique is proposed that makes it possible, taking into account the forces acting in the piston ring – cylinder sleeve contact zone, to determine the height of the notch on the working surface of a structurally modified piston ring, which reduces the friction force.

The article is devoted to understanding the anthropological features of the teaching profession. Despite the long history of pedagogical activity, one can state its plasticity, variability in professional content, but not in its essence. The fundamental basis of the teaching profession is its attribution to acts of vocation and recognition. Based on the methodology of social constructivism, statistical data, indicators and indices, the following has been recorded: a variety of images and models of a teacher among age and other cohorts; disproportion between the social image of a teacher in modern Russia and the real practice and models of the profession that carry out the socio-economic production of education and knowledge. The identified discrepancy allows us to speak about the need to create a concept of the teaching profession that would correspond to the rapidly changing world. As a result of the study, the most well-known and popular approaches to the analysis of recognition-vocation (religious-symbolic, rational-ethical) were identified, and it was shown that the development of a «recognition paradigm» in the study of the anthropology of pedagogical activity has great potential. By extrapolating the ideas and hermeneutic analysis of P. Ricoeur, an explication of two figures of recognition in the possible anthropology of the teacher’s skill was made: «Self-recognition of oneself as a teacher. Reflection and responsibility» and «Mutual recognition». In conclusion, it is shown that the models of a teacher as a profession-vocation (mentor, master, virtuoso) existing in the modern world are initially rooted not in the systems of social qualifications, but in the communication and reciprocity that creates the unique face of the teacher and the student

The development of the physical foundations of remote diagnostics of areas of plastic pollution of reservoirs has now become highly relevant due to the increase in anthropogenic pollution of the World Ocean. The pollution is largely related to the polyethylene (PE) films, which can affect to variability of the radar scattering signal when probing the sea surface, which can be used to diagnose plastic areas. PE films are often located in the near-surface layers of water, rather than floating on the surface, despite the fact that their density is usually less than the density of water. This paper presents a numerical study of the dynamics of a small floating PE film in the field of surface waves. The open source software “OpenFOAM” was used as a numerical modeling tool. It was found that the film floats in the absence of waves, but if there are any surface waves, it can sink, float, or be in the equilibrium at some depth. The detected effect indicates the occurrence of an additional force in a fast oscillating wave field, which is directed against buoyancy forces and depends on the steepness of the wave and the depth of the initial film location.

The aim of the study is to describe evaluation in the metacommunicative aspect within German scientific and journalistic discourse. The article analyzes complex sentences with causal subordinate clauses, which serve as means of argumentation and justification in expressing cause-and-effect relationships, where various types of evaluation (positive and negative, subjective and objective, rational and emotional) are explicitly conveyed. In complex sentences with causal subordinate clauses, evaluation functions as a secondary layer of meaning alongside the primary meaning and the syntactic relations arising between the main and subordinate clauses, allowing evaluation to be considered as a metacommunicative tool in the realization of scientific and journalistic discourse. The scientific novelty of the research lies in demonstrating the interrelation between the categories of subordination and evaluation, whereby the established type of cause correlates with a specific kind of evaluation. The results showed that the metacommunicativity of evaluation is marked by the position of the subordinate clause relative to the main clause, the semantics of conjunctions, lexical content, and context. The study identifies linguistic means of rational and emotional evaluation and proposes a classification of evaluations based on the types of causal subordinate clauses distinguished.

The analysis of available works in the literature, including our own, was carried out, on the basis of which this review article was prepared. The interest shown in the processes of oxidative synthesis at high anodic potentials is associated with the production of various types of organic and inorganic, including mixtures of organo-inorganic compounds. The problem of electrochemical introduction of the NO3 group into the molecules of organic and inorganic compounds, which are valuable products used in various fields of technology, is relevant. The electrochemical route to the synthesis of such compounds is complicated by the fact that, unlike perchloric and sulfuric acids, the anodic behavior of NO3 - has not been sufficiently studied. One of the reasons for this is the impossibility of obtaining reliable experimental data when using electrochemical cells in which the interelectrode spaces are separated by a glass porous diaphragm. The products of cathodic reduction, penetrating through the diaphragm into the anolyte, are oxidized by oxygen formed at the anode and significantly affect the reliability of the data obtained, in particular, the current yield (CO) of oxygen. Electrochemical cells in which the interelectrode spaces are separated by cation-exchange membranes have been developed and manufactured for the first time. In this case, the possibility of reduction products getting into the anolyte is excluded, which leads to reliable results. Only electrochemical cells of a new design, allowing reliable data to be obtained, were used in the studies. The direct (radiochemical) method proved the participation of nitrate ions in the anodic process - the oxygen evolution reaction (OER). It is shown that NO3 ions participate in the OER in two ways. The analysis of the complex of the obtained data made it possible to propose a mechanism for the oxidation of nitrate ions.

The article considers the urgent task of increasing the efficiency of operation of traditional dual-circuit cooling systems of marine diesel engines using closed external circuits with the rejection of the flow-through system of sea water. There are different methods that allow using closed external cooling systems, which mainly differ in the method of removing heat from the coolant of the internal cooling circuit. The presented main types of cooling systems with an external closed circuit differ in their design. The area of vessel operation can be a decisive factor in choosing a suitable option from the types of cooling systems with a closed external circuit presented. The main types of marine cooling systems with a closed external circuit are analyzed, which differ in composition and operating principle. An overview of the advantages and disadvantages of each system shows the directions in which it is possible to work on improvement during such modernization of cooling systems. The principles of technical solutions adopted in the development of basic diagrams of cooling systems with a closed external circuit are presented. The possibility of using a new type of cooling systems based on the principle of abandoning the external circuit with the expansion of the functionality of the internal circuit in the design and modernization of marine cooling systems is considered, especially for certain areas of vessel operation. A cooling system with heat removal into the air is proposed. Closed cooling systems ensure environmental safety, since during their operation there is no discharge of wear products of ship parts and other harmful materials, such as fuel and oil, together with seawater into the open water area.

The stern tube bearings, which serve as supports for the propeller shafts of the ship's shafting are examined and studied. The main geometric and mechanical parameters of stern tube bearings are indicated. It is noted that the choice of material and geometric dimensions of stern tube bearings, in addition to the operating conditions of the vessel, are taken on the basis of the requirements of regulatory documents and taking into account the results of static and dynamic calculations when designing a ship shafting and its auxiliary elements. A static calculation of a beam of length L is carried out in relation to ship shafting. It is noted that the operating condition of the shaft line and the entire ship's power plant depends on the gap between the facing layers of the propeller shaft and the antifriction material of the stern bearing, which increases when the latter wears out. To carry out static calculations, the initial parameters method is used. Based on the boundary conditions of the beam under study, a system of inhomogeneous equations is obtained. A general approach to the static calculation of a beam is presented, which rests on hinged supports offset relative to the beam axis by an amount Δ. It is indicated that the displacement of the supports relative to the beam axis models the amount of wear of the antifriction material of the stern tube bearing. Based on the results obtained, an assessment of the influence of stern tube bearing wear on the stress state of the shafting and on the load on the support bearings is provided. The fracture shape of the propeller shaft during torsional vibrations is presented. It is indicated that dynamic calculations for transverse and torsional vibrations are the final and verification stage in the design of a ship shafting and its auxiliary elements.

. Nonlinear consumers of electrical energy of significant capacity when operating as part of a single marine electric power system (MEPS) have a strong impact on the quality of the generated voltage, which is characterized by various electrical parameters, including the coefficient of nonlinear distortion (KND). When powered from such a network, distortion of signals from radio navigation equipment and control systems may occur, reducing efficiency of electric motors, generator equipment and electric energy consumers, deterioration of cable networks, etc. By changing active and passive methods of compensating for nonlinear voltage distortions, the influence of nonlinear electric power consumers on the voltage quality of the generated electric power at the MEPS can be reduced. One of the effective ways of compensation is the use of an active nonlinear distortion compensator, which allows you to reduce the KND to values of 4-5%. The use of a two-channel measurement and control system in an active compensator based on a voltage-boosting device is an effective way to compensate for nonlinear distortions. A new, different from the known, block diagram of the nonlinear distortion compensator is proposed, on the basis of which a simulation model of the ship's electric power system was developed in the Simulink application package of the MatLab graphical simulation environment. Simulation modeling has shown that the use of a two-channel control and measurement system makes it possible to reduce the level of nonlinear voltage distortion of the generated electricity to 2-3%, with the power of nonlinear consumers not exceeding 60% of the power source. Increasing the power of the voltage-add transformer of the active compensator under the same conditions makes it possible to reduce the coefficient of nonlinear distortion by 0.5%.