To solve scientific, technological and environmental problems in the field of road transport, it is necessary to develop new mathematical models. At this stage of development of internal combustion engines and their parts, it is necessary to model complex hydrodynamic technologies. This necessities revealing different forms of liquid and gas flows with arbitrary initial and boundary conditions for the region under consideration.
The work is devoted to modelling a turbulent flow over a plate located in a cylinder. Reynolds-averaged Navier-Stokes equations were used as a mathematical model of the flow. Turbulent viscosity was calculated using the one-equation Spalart-Allmaras turbulence model. To solve the system of hydrodynamic equations, the finite difference method was used. A numerical method for calculating plane flows of viscous gas in a cylinder using turbulence models is presented. Suitable options were selected based on physical assumptions used to develop the models.
Recommendations have been developed on the possibility of using the considered turbulence models.

One of the priority tasks in development of railway transport is to raise its efficiency by increasing the time between repairs for both the track superstructure and the rolling stock. Solving this problem is impossible without timely, complete, and reliable information about the dynamics of interaction of the rolling stock with the infrastructure. To organise monitoring of dynamic processes, completely different types of primary transducers are used: resistance strain gauges, fibre-optic sensors, dynamometers (force sensor pads), accelerometers, acoustic emission sensors. This implies relevance of the scientific and technical problem of comparative testing of sensors of different types to assess the information content of their signals and justify the criteria for choosing primary transducers when solving specific monitoring problems.
The objective of the study is to comparatively test removable resistive strain sensors, optical polarisation strain sensors and accelerometers under a passing train and to evaluate their information content to control rail depression and detect defects on the running surface of wagon wheels.
The study using finite element modelling and a physical model of a rail as of a beam on an elastic foundation, substantiates the relationship between longitudinal deformations and vertical accelerations of the rail foot. Comparative tests of removable strain-resistive and optical polarisation strain sensors and accelerometers were held on an experimental section of track under a passing train. A signal processing algorithm has been developed and the equivalence of strain gauges and vibrometers for determining the depression of a rail under a passing train has been proven. Acomparison has been made of the pulse components of the signals of deformation and vibration acceleration during movement of a wheel with a defect on the running surface, and the requirements for the frequency characteristics of the sensors and their mounting on the rail surface have been substantiated.

This article examines the influence of loads, conventionally divided into static and cyclic ones, and of corrosion acting together on the structural elements of metal structures of metro escalators. The dynamics of corrosion processes are determined by the environment, the degree of influence of which, depending on the geographical location and based on seasonality, can vary from non-aggressive to highly aggressive. This, with simultaneous occurrence of deformations (a stressed state is created in the structure), can lead to fatigue failures. The state of the metal structure of the escalator in this case is the most important element, since the failure of almost any of its structural elements means a complete stop of the escalator.
The prerequisites for corrosion fatigue for low carbon steels, as the main material in manufacture of metal structures for metro escalators, are also considered.
The main objective of the study is to search for criteria for creating an experimental and computational method for determining the residual life of metal structures of metro escalators with a high degree of reliability. Identification and analysis of criteria for assessing the condition of metal structures was carried out by the authors using experimental research and survey methods, that resulted in a conclusion that the degree of degradation of the main characteristics and properties of metal structure elements is determined not only by the number of loading cycles, but also by the duration of exposure to an aggressive environment.

New principles of train separation allowing for capacity increase are in high demand under the conditions of infrastructure constraints, considering also ever-growing freight turnover at the Eastern segment of railway network.
Currently, the most promising option is train separation based on virtual coupling technology, which, according to calculations, can provide an increase in carrying and transit capacity of up to 20 % compared to the classical technology of rigid coupling. At the same time, there are no methods for determining the use cases for applying the virtual coupling technology for specific sections of the railway supported by mathematical calculations.
The article discusses five use cases for virtual coupling for sections with speed limits and presents graphical estimates of capacity for various speeds and lengths of sections with speed limit. It is concluded that virtual train coupling is advantageous for capacity increase on sections with infrastructure constraints, and further research is needed to justify the practical methods of its application.

Based on the analysis of recommendations of the International Civil Aviation Organization on a reasonable reduction in sizes of ILS critical areas and identification of shortcomings of the existing requirements of the Russian Federal Aviation Regulations for critical areas of ILS localiser and glide path (glide slope), a procedure has been developed that allows assessment localiser and glide slope bends for shortened critical areas. The assessment comprises the influence of different reflecting objects situated on operation area of the aerodrome, as well as of aerodrome environs on the operation of the ILS localiser and glide path.
Reflecting objects can be approximated by models of a wall (that simulates reflections from buildings, bridges, fences), of a cylinder (that simulates reflections from factory pipes, tanks, containers, aircraft fuselages) and of a hemispherical diffuse reflector (simulates reflection from elevated terrain).
The procedure was tested for Gorno-Altaisk aerodrome, and aproposal was developed to reduce the critical area of the localiser, which will expand the apron by 35 m, eliminate problems with imposed speed limits and blocking movement of aircraft on the taxiway. Also, the probability of service failure will decrease by 3…11 times, and the runway occupancy time will decrease by 12,5…26 % compared to existing features.

The article is devoted to the study of the process of technical preparation preceding scheduled preventive maintenance of newly commissioned double-deck passenger coaches. The paper considers the main tasks and goals of technical preparation, including the step-by-step process of car repair, as well as repair planning, formation of a range of applied materials, tools, and step-by-step control of work performed during repair and maintenance. Upon identifying features and inconsistencies that arise during technical preparation for repair of double-deck coaches of a new model range, ways to solve them are proposed.
The paper considers the main directions in organisation of preventive maintenance in terms of implementation of measures to integrate into the process the features associated with the specifics of the assemblies, parts and materials used in those coaches; main tasks of preparing for scheduled preventive maintenance with regard to provision of workshops, of developing forms, methods and adjusting production processes, as well as of employing small-scale mechanisation tools, and manufacturing devices to speed up the repair process. The processes of carrying out scheduled preventive maintenance are structured allowing development of a process model for repair of a double-decker coaches when they are delivered at maintenance and repair facilities.
The study allows regulating and improving the efficiency of technical preparation for repair of double-deck coaches, ensuring higher quality and speed of repair work, as well as effectively assessing the real need for spare parts and materials used during the repair process, since the operation of these coaches provides for a new set of spare parts, materials and elements in comparison with single-deck analogues already manufactured.

Digital transformation strategies have been developed and approved in the federal constituent entities of the Russian Federation. The strategy of digital transformation of the Republic of Dagestan has comprised transport among main areas.
The strategy of digital transformation in the field of transport involves introduction of navigation systems on public transport, ensuring the comfort of passenger travel, including ease of payment, and reduced waiting time.
Research has shown that in recent years the number of road traffic accidents in the mountainous regions of Dagestan and their severity has increased. This is due to an increase in the number of cars operated on the road network of the Republic, especially by motor tourists, a decrease in driver discipline, and the low level of development of telematics systems and digital infrastructure on mountain roads.
In this work, the authors have proposed organisational, technical and engineering measures for development of digital infrastructure for the mountainous road conditions of the Republic of Dagestan, which include the creation of a Situation Centre in the Traffic Control Centre (TCC) with introduction of an automated transport mobility management system, systems for monitoring meteorological and road conditions, installation of dynamic information boards, updating of navigation maps and enhancement of the functions of voice messages.
The implementation of the proposed measures will improve transportation and road traffic safety when transporting passengers in the mountainous areas of Dagestan and reduce the number of road traffic accidents.

The article examines the essence, characteristics of normative legal regulation and problematic aspects of implementation of military transport obligation in the Russian Federation. The author notes that in difficult modern conditions, fulfilment by citizens and organisations of their constitutional responsibilities to ensure the defence of the country and the security of the state is an important area of preserving the sovereignty and territorial integrity of Russia. The social, historical and legal roots of military transport obligation are described. It has been studied that in Russia, the legal acts at the federal level have established necessary regulatory and legal requirements, characterised by completeness, accessibility for acquaintance and general elaboration of regulated issues. Military transport obligation in the country has been established to provide state armed forces with vehicles during the period of mobilisation and during wartime. The paper substantiates that military transport obligation appears to be an important structural and functional construct in the material, technical and regulatory support of the country’s defence capability and state security. The author has formulated specific proposals for improving the current state legal regulation of the issue under consideration, to increase the level of mobilisation readiness of vehicles and ensure better performance of military transport obligation.

Modern problems of railway transport in Russia, such as the general technical condition of transportation assets, and relevant issues of their safe operation, substitution of imported equipment and its components, implementation of the programs of technological development give rise to the need to create new equipment and technologies, constructing schemes for long-term development of transport based on new safety requirements and strategic planning. Current level of developments does not allow to completely eliminate damage, failures and accidents regarding railway transportation assets manufactured in accordance with the current regulatory framework. Solving these problems is possible by identifying the actual state of an object regarding cyclic, corrosion, wear and other damage accumulated during operation, which determines the onset of limit states of the basic elements of an asset, taking into account resource recovery technologies at various stages of the life cycle, both in standard (design) operating conditions and beyond them.
The article refers to the problems associated with ensuring safe operation of railway transport, with the aim of substantiating based on existing regulatory and technical documents of new approaches to the analysis of damageability, vulnerability of objects and assessment of the risks of accidents and disasters. The development of interaction through a system of new problem statements and regulatory and technical documents, as well as more active involvement in the use and development of the fundamental laws of physics, chemistry, and mechanics of real-life processes in the environment, make it possible to implement new concepts, strategies, and developments of advanced research for technical objects with the use of digital and intelligent technologies.

The article examines the economic and environmental consequences for the Russian Federation that may be caused by the transition of road transport to natural gas fuel and electricity. According to strategic planning documents, public authorities are pursuing the policy aimed at converting a significant share of road transport to natural gas fuel. As singled out, this policy is mainly motivated by the issues of limiting emissions of harmful substances into the atmosphere from the combustion of oil products. In addition to a positive impact on the environment, this transformation should have a positive impact on the economy, since the use of alternative energy sources reduces transport costs, and construction of the necessary related infrastructure will create additional growth points for the economy.
The objective of the study described in the article is to investigate the economic and environmental effects for the Russian Federation from the transfer of road transport to natural gas fuel.
Main economic indicators analysed comprise subsidies that are necessary to create conditions for development of the relevant market, changes in budget revenues from the mineral extraction tax and excise duty on oil products, as well as additional gross value added due to multiplier effects in the economy. The study of environmental effects consists in assessing the reduction of emissions of greenhouse gases and particulate matter into the atmosphere.
The analysis of the effects for the Russian economy from the transfer of road transport to alternative energy sources has shown that due to the multiplier effect, for the period up to 2035, gross value added will increase by 3,6 trillion rubles, and investments in the necessary infrastructure will amount to about 2,7 trillion rubles, which is about 13 % of the projected investment in the road sector. Due to the use of gas motor fuel and electric vehicles, by 2035 СО2 (carbon dioxide) emissions will be reduced by 11 million tons annually, which represents only 0,5 % of nationwide emissions. This means that the transfer of road transport to alternative energy sources is not effective enough from the point of view of the existing motivation, and the motivation must be changed in favour of positive economic effects.

Today, road transport is one of the main environmental pollutants. It accounts for more than half of all emissions. In this regard, the issue of developing measures to reduce the impact of cars on the environment is gaining relevance. There are various approaches to solve this issue, but the most promising direction is the use of electric vehicles. It should be noted that we cannot talk about their absolute environmental friendliness, since there is still an indirect impact on the environment.
The paper examines the prospects for the use and disadvantages of two types of electric vehicles powered, respectively, by battery or hydrogen fuel cells. Currently, production of battery electric vehicles is a more popular direction, which is largely due to development of technologies in the field of battery production. At the same time, one should not completely exclude other areas, such as hydrogenfuelled vehicles. Such vehicles are distinguished by good environmental friendliness, which is determined by the nature of the combustion product and the possibility of obtaining this type of resource. However, the use of hydrogen as a fuel for internal combustion engines is not relevant. Development of a car with an electrochemical generator is more promising. Today, a fairly large number of the world’s leading car manufacturing companies are advancing in this direction.
The electric vehicles considered in the work have similar emissions of harmful substances, which, under equal conditions, approach zero. However, both types of vehicles leave a carbon footprint, the bulk of which comes from electricity generation and hydrogen production. The study carried out a comparative assessment of the quality characteristics, carbon footprint and operating costs of electric vehicles with various types of power plants under Russian operating conditions. Based on the comparison, the main advantages, and disadvantages of those types of electric vehicles have been identified. Actions are proposed to increase the environmental friendliness of electric vehicles and solve problems that complicate their operation.

The objective of the study is to evaluate the emissions of pollutant gases (CO and CO2) when using fuel mixtures (ethanol-petrol) in internal combustion engines. The experiments were carried out in the Engine Laboratory of the Faculty of Engineering Sciences of Agrarian University of Havana (AUH) using JACTO engine. To obtain the amount of toxic gases emitted into the atmosphere (CO2 and CO), the balance of the combustion equations was proposed for the different mixtures estimated taking into account the established coefficients of excess air. The analysis of the combustion process based on 10, 20 and 30 percent ethanol mixtures with hydration (80%; 85%; 90 %; 95%) and conventional petrol of category B-85 for rich mixtures (α = 0,85) and for lean mixtures (α = 1,15) showed that CO2 and CO emissions to the atmosphere are reduced to 17% for considered mixtures as compared to petrol. Despite higher relative fuel consumption as compared to petrol, there is a significant positive environmental effect.

Transport has played a very significant role in formation and development of ancient and medieval civilisations. At the same time, since ancient times, the transport factor has contributed to advancement of various social communities and societies (manifested in achievement of leadership by the corresponding cities, regions, countries) and formation of the «advancement effect», the essence of which is the possibility of more efficient use of available resources and implementation of existing advantages to ensure successful development.
The influence of transport on formation of the «advancement effect» of societies is based on a wide range of socio-economic effects that are generated during movement of goods and passengers. These include, inter alia, adding value to goods as a result of movement, stimulating growth in the volume, scale and efficiency of goods production, disseminating knowledge, ideas and stimulating innovation.
Because of the effects generated by transport activities, the centres of this activity develop rapidly and achieve economic, and often also political and cultural leadership. At the same time, transport leadership is associated both with geographical location and with socio-economic (primarily institutional) conditions that provide the opportunity to implement the benefits of the geographical location.
The provided analysis covering approximately five thousand years of existence of ancient and medieval civilisations, using many examples, showed that transport indeed played an important role in advancement of certain societies localised within cities, regions and countries. Their advancement to leadership positions was achieved due to the synergy of an advantageous geographical location, innovative development of technical means of transport and institutions that facilitate the efficient conduct of transport activities and development of transport and commercial ecosystems. In turn, the cessation or significant weakening of the beneficial effects of the transport factor led to the loss of leadership positions by societies and the decline of the corresponding economic centres.

The article systematises and analyses information reflecting the main approaches to preservation and presentation of monuments of transport history during the period of «perestroika». It was during this period that various social practices emerged in the field of preserving technical monuments, which later became traditional. The author examines several important anniversary events related to the history of transport, during which numerous historical rarities were identified and preserved, and new museums and exhibitions were created.

Archival publications
A reproduced report in the Imperial Russian Technical Society was first published in the Railway Business [Zheleznodorozhnoe delo] journal in 1892. It is dedicated to the activities of Nikolai. A. Belelyubsky, a well-known bridge engineer who made a significant contribution to the development of transport engineering in Russia, and whose biography can excellently help to trace the evolution of Russian railway bridge construction in the 19th century.
The author of the report was Andrei N. Gorchakov (1836–1914), who held the positions of head of the military road department of the field administration of military logistics of the acting army, engineer of the Ministry of Railways, was a member of the board of state railways, managed private railways, and was director of the ministerial railway department.
The author’s punctuation and vocabulary are preserved as much as possible in the text.

Paraskevov, A. V. Improving road traffic management based on the use of mathematical and instrumental methods of economics [Sovershenstvovanie upravleniya dorozhnym dvizheniem na osnove ispolzovaniya matematicheskikh i intrumentalnykh metodov ekonomiki]. Moscow, Vologda, Infra-Inzheneriya publ., 2023, 84 p. ISBN 978-5-9729-1283-4.
The article is a review of the monograph «Improving traffic management based on the use of mathematical and instrumental methods of economics», written by A. V. Paraskevov, a senior lecturer at the Department of Computer Technologies and Systems of the Kuban State Agrarian University named after I. T. Trubilin and published by Infra-Inzheneriya [Infra-Engineering] publishing house. The work summarises and systematises extensive material on innovative methods for improving management of road traffic congestion levels. An also considered application for motorists is designed to build optimal routes taking into account the current situation on urban roads.