Pavel Kravchenko’s research while affiliated with Saint Petersburg State University of Architecture and Civil Engineering and other places

Until recently, the digitalization of distributed process facilities in the oil and gas industry implied equipping the facility with a digital constant power supply control system. At present, increased requirements for industrial safety as well as technical, administrative, and economic difficulties in external power supply for the distributed facilities of the gas transport system have led to the need to create digital remote control systems capable of operating on power sources using renewable resources (solar or wind energy). The paper describes theoretical studies and presents the results of the technical implementation of new remote control systems for gas well clusters, single wells, single and twin gas pipeline branches. The current development level of intelligent process control systems makes it possible to accumulate large volumes of primary information for subsequent analysis and solution of control problems both in normal and emergency situations. In this case, a high probability of correctness or the greatest effectiveness of the decisions made is ensured. The paper considers the process of gas transport via a trunk line, carried out by a gas transport enterprise, and the process gas gathering via an inter-field line of a gas field, carried out by a unit of a gas production enterprise, as examples, for which a Decision Support System (DSS) is created.

A vehicle as an object of increased danger is highly susceptible to violation of operating rules, which causes a decrease in its level of safety and environmental friendliness. Safety-enhancing components, assemblies, and systems increase design complexity and the cost of maintaining a vehicle in good condition, which in turn significantly increases the cost of spare parts and components. Maintenance of these units reduces their maintainability. To assess the life cycle of a vehicle, it is necessary to test its service life management system in dynamically changing environmental conditions. In terms of these problems, the choice of a solution depends on the state of the environment and involves solving a number of multi-criteria problems using various methods of optimization and mathematical modeling. To increase the reliability level of decisions necessary in the service life management system of a vehicle, it is advisable to develop an analytical apparatus based on linear programming methods and the search for a set of Pareto optimal solutions (development of zoning methods), which will make it possible to arrive at optimal decisions given insufficient data on the operating conditions of the vehicle. The study represents an attempt to use a new mathematical apparatus for qualitative identification of the impact of external relations determined by the vehicle operating environment directly on the nature of the technical operation of the vehicle. Both processes are considered as complex dynamic systems forming connections, therefore it was necessary to adapt a number of existing approaches to solving multi-criteria problems of technical operation of vehicles necessary for the consistent implementation of computer modeling for the operation of the service life management system of a vehicle.

“The fundamental principle of systems thinking is the ability to look at events, objects and phenomena from various perspectives considered as an aggregate” (O’Connor and McDermott 2006). The article continues studying the issue of preventing the occurrence of causes of death on Russian roads, i.e. “zero” mortality. The study results are presented in a series of articles published in the “Transport of the Russian Federation” journal. It provides a rationale for the feasibility and relevance of applying a methodological approach, which is new for Russian science and practice, to solving the issue of ensuring road traffic safety (RTS) in the interpretation of its meaning, comparable with the meaning of the term “zero mortality”, namely, a multi-faceted approach that considers a multilateral assessment of the quality of management decisions adopted using the knowledge of a full set of different opinions on the objects of any complexity being studied. They include RTS assurance systems, for which a set of different opinions (aspects) regarding all their possible facets, sides, properties, features, etc. — on behalf of the state, authorities, operating structures, and society — can be transformed into a set of factors affecting the level of provided RTS, having a subset of “dangerous” factors that can become causes of death in road traffic accidents (RTAs) in the road traffic environment. The article contains: a digest of the above subset of factors, which are essential for the issue being studied and can serve as the basis for expanding the possibilities of forming a set of death causes, adjusting the functions and corresponding types of required activities functionally bound by a common goal; substantiation of a functional and structural mathematical model for the state RTS system, an algorithmic model for the mechanisms forming its main functional properties and subsets of non-accidental causes of death, which can be understood and addressed preventing the moment of a possible serious RTA, and accidental ones, which cannot be understood and addressed; a “starting” sample of literary sources, capable of expanding (when referring to the publications) and ensuring an increase in the progress of solving the issue of “zero mortality” on Russian roads by 2030 as established by the state strategy for RTS.

The systemic approach described in the article is designed for the development of an effective approach and purposeful measures to ensure road traffic safety. The need for a systemic approach to auditing road traffic accident black spots is justified. A conceptual model of the systemic approach to auditing road traffic accident black spots is developed. This model includes interrelations of subsystems, factors of accident-prone situations, causes of the emergence of road traffic accident black spots in the system “road user – vehicle – road – external environment”. A hierarchy of interrelations and flows in the system ensuring road traffic safety is suggested. The authors suggest considering the “Road User – Vehicle – Road – External Environment” system that includes such subsystems as the Driver (D), Pedestrian (P), Child Pedestrian (PC), Vehicle Passenger (PassV), Child Passenger (PassVC). They also suggest using the traditional term “Car subsystem” as the Vehicle (V). To account for the entire content of the “external environment” (EE) subsystem, the following structure is suggested: road infrastructure (RI) reflecting the conditions and parameters of traffic management as well as existing weather and climatic conditions. The systemic approach to auditing road traffic accident black spots reveals the potential of improving this mechanism.

Using the functional series of transportation energy efficiency estimates based on the Bartini’s LmT⁻⁴-Table entities, the author developed a method to assess sections of combined transportation according to the criterion of energy consumption with account for the squared speed of freight movement. The possibility of comparing values of specific energy consumption for different transport modes is evaluated. The results of the comparison make it possible to identify weak points of combined transportation as well as starting points for transportation plan improvement. A numerical analysis is carried out using an illustrative example of combined transportation involving container ships, automobile and railway transport. Modeling and calculation are carried out using the EcoTransIT calculator within the well-to-wheel boundaries. The author provides recommendations on further extension of the concept and introduction of energy efficiency index into the transport service life cycle assessment (LCA) methodologies.

The paper addresses techniques for applying structural methods to study complex systems of various purposes to substantiate functional organization and control. Those systems include traffic safety assurance (TSA) systemsin general, their individual control channels managing the level of traffic safety ensured by main macro factors affecting it, as well as their individual functional elements. The logic of developing a complete set of causes behind grave road accidents, both primary and final, which is missing in the Russian practice, is presented Typical models of setting up the organization of controlled, functionally compulsory activities of various kinds, and a structural mathematical model developed for a fully observable system that provides an opportunity for the determination of mechanisms underlying the formation and digital evaluation of its main functional properties, such as controllability, accuracy of conversion of input, controlling and disturbing signals into the final, systemic and local results, are provided. A structural and functional model of a nation-wide multi-channel system to ensure traffic safety as the basis to support all functional properties and procedures for breaking-down into various functionally separate subsystems at any level of the hierarchy is described.Main advantages of using methods for the functional and structural modeling of systems, relevant for practical tasks,are shown. Among those advantages are the following: the possibility of using those methods in systems of any category and designation ranging from technical, man-machine, and organizational systems to large systems — combinations of complex systems having different functional (internal) organization. It is shown that they can be presented in a digital format and used to carry out system researches in the absence of initial information. Organizational management systems, where linguistic variables are taken as functions of transforming input signals into output signals, can be given as an example. Such linguistic variables change in the range of "1,0", boundaries of which correspond to activities performed in accordance with the requirements established or not performed at all.It is shown that,in systems of organizational management,the latter advantage can be implemented rather easily in terms of procedures. Moreover, it is able to ensure the transformation of non-systemic activities on traffic safety assurance into strictly systemic activities, i.e. into transparent, observable, predictable, and capable of continuous improvement activities up to the status where the "zero mortality" on Russian roads is achieved.

The paper addresses an issue of substantiating the method of monitoring and digital evaluation of the influence of the technical state of automated combined steering systems in heavy-duty and urban passenger vehicles, that use channels of hydraulic booster (HB) steering installed in parallel with a mechanical channel, on traffic safety (TS) and efficiency of vehicle operation in the mileage interval between scheduled technical inspections. It is demonstrated that the maximum value of discrepancy in the HB set by the driver (within the limits of mandatory, functionally set artificial "gap" in a "spool–sleeve" pair, controlling the energy of the external source, i.e. a hydraulic pump) reduced to an angle of steering wheel rotation is negligibly small as compared to the size of the gap in the steering system as a whole; the latter is used to evaluate the compliance of this system with the traffic safety requirements. The specified value of the artificial gap does not exceed one degree in rotation of the steering wheel having an HB of a rotary type; it has a significantly smaller value for axial HBs (where the displacement axis of the spool coincides with the sleeve axis). Given that the value of the gap in the steering system is regulated by state standards and lies within the range of 15–20°, which considerably (more than one order of magnitude) exceeds the artificial HB gap, the contribution of the HB channel into the total gap value in the steering system is negligible, and accountably lies outside the area of operators’ attention. Therefore, a conclusion can be made that the evaluation of the above-mentioned gap, taking into account the physics of the operating HB, should be carried out according to other criteria that are not related to gauging the gap. It is shown that the feedback from drivers complaining on growing labor intensity of driving cars having HBs and long mileage, complying with the effective state Standard requirements under the current manufacturing technology can be used to substantiate the limit state indicator for steering systems using the criterion of vehicle controllability reflecting the level of the psychophysiological load. The paper demonstrates that the current practice of monitoring (preventing) the onset of reaching the limit technical state by the HB, assessed by the value of allowable drop of fluid pressure in the hydraulic system (relative to the pressure set by the limiting controller) detects the defect with delay exceeding a 100.000 km mileage with respect to the moment of evaluating the admissible controllability level determined by the driver according to his/her individual psychophysiological load. The paper reports results of bench tests of HBs having various mileage and results of road tests carried out using large capacity buses having HBs differing in mileage on an actual urban route. A mechanism of correspondence between HB parameters and the bus mileage with the level of the driver’s psychophysiological load and the energy spent by a driver to drive a vehicle, which allows estimating limit states against the criterion of vehicle controllability, as well as estimating financial losses of a company operating urban bus routes when the level of the actual driver’s load exceeds the allowable level.

The Article describes a multi-level systematic organization of traffic safety activities. The grounds are given to support the concept of current system status observability by monitoring the functionally necessary activities in all the traffic safety system hierarchy levels. The functional configuration of the traffic safety system in also proved to be the means for converting the objectives into desirable results of the system functioning in terms of the controlled (cybernetic) system theory. A procedure is presented to demonstrate using of the schematic diagrams to support the mechanisms of formation of the basic system functional properties, such as controllability, accuracy of performance by input signals, noise immunity etc., that are not presently applied in real traffic safety practice, but are able to significantly enhance the functional capabilities of the traffic safety systems, and therefore to prevent death cases in the road traffic.

The results of classification investigations of the efficiency of the traffic management schemes (TMS) are provided according to the criterion of their conflict loading (CL). The latter is determined by types and number of conflict points and maneuvers allowed by the Road traffic regulations in traffic and pedestrian streams. X- and T-shaped one-level signal-controlled junctions (SJ) of streets and roads have been examined in megapolises having various methods of traffic management. Among them there are single-phase management, management in separate directions and combined traffic management in regulatory restrictions of levels of requirements to traffic safety. TMS classification is developed for a complete group of options to formulate and solve the management problems.

The issues of optimizing road cargo flow of the transport and logistics cluster (TLC) of a port metropolis, for example, St. Petersburg are regarded. The need to clear the central part of the city of warehouses and freight lines, to transfer them to the ring roads area is highlighted. Being the hub of the international transport corridor (ITC), St. Petersburg requires the implementation of "Foreland-Hinterland" and "Hub-and-Spoke" logistics concepts. Special emphasis is placed on the need to optimize the allocation of traffic flows and the possibility of solving this issue in the GIS ArcGIS environment. The issue of justification of withdrawing the routes of the cargo flows from the city center to the ring roads is solved quantitatively.