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The paper reviews the road traffic accident registration form and discusses existing practices carried out in Uzbekistan. The popularity of mobile phones/tablets and internet technologies in daily use and their increasing power in terms of speed and memory could assist efficiency and accuracy in the road traffic accident data collection. The authors review up-to-date mobile/internet technologies for the road accident data registration and propose a novel approach that covers various data sources including police data, hospital data, road department data, insurance company data, transport company data and social media data. The proposed approach integrates all the data into a single system (database), which can be used for public audit and research purposes.

The article presents a method of experimental research and created stand with metrological equip-ment that allows to simulate the complex process of milling asphalt concrete samples by force and coordinate closure. As a result of the research, regression equations describing the milling parame-ters of asphalt concrete samples, were obtained. It is established that during the transition from the power (elastic) closure of the technological system to the rigid (coordinate) one, milling errors de-crease by up to 15 % and their spread is up to 30 %. The developed method for restoring the road surface can be applied in practice not only within Kazakhstan, but outside the country, as well.

The paper presents the research on revealing the causes of belt conveyors downtime at open-pit mining operations. By results of researches it is established that the reasons of the above mentioned problems are technological dust formed at crushing of mineral ore, further loading and unloading, and also at transporting by conveyors. Dense dust-air mixture settling on the rotating mechanisms of conveyors, gets into the bearing units and on the surfaces of friction gears, which accelerates the process of wear of parts several times.

The study carried out an analysis of the vehicle traffic parameters on a national road in 2011-2016. The variability and uncertainty of results were evaluated. An analysis of traffic data recorded on the city's entry and exit lanes was carried out. The variations in traffic volume are of interest e.g. in dynamic traffic management systems and navigation services, examining the benefits of flexible work time and places and assessing the environmental effects of traffic congestion. Research has shown that the assumption that lanes perform equally is not always true. Traffic volume models should be periodically calibrated taking into account the shape of the daily profile, which may, for example, allow public transport timetables to be more responsive to the needs of travelers.

The paper addresses the driving dynamics of emergency fire trucks. It focuses on the issues of braking, measuring real braking distances and calculating adhesion coefficients. It presents the results of measuring the real braking distances for firefighting vehicles - type water tenders. Measurements were taken on dry asphalt and depending on the vehicle's speed of travel. Experiments were conducted on five types of firefighting vehicles. The results of measurements are mainly used by fire protection units to the drivers' self-education to improve safety when driving to intervene.

In this paper the selected results concerning the analysis of the phenomena occurring between the road and the wheels of a motor vehicle have been presented. The analysis was prepared for the simulation of the acceleration maneuver with the 100 % (full) throttle along the road with various conditions. The aim of this paper was to analyze whether both the full throttle and the road conditions may affect the forces occurring in the contact area between the wheels of the vehicle and the road, regarding the road conditions and the rear wheel drive of the analyzed vehicle's model.

The publication presents the results of research into the strength of an improved tank container. The tare of a tank container can be reduced through application of composite material for the tank. In this case its mass can be 46% lower than that of a metal tank. The strength of the tank was calculated by computer simulation. The maximum stress occurs in its lower part and is about 295 MPa.

This research proposed bacteria-treated concrete, which is highly desirable because the mineral precipitation induced from microbial activities is pollution free and natural. This study investigates the effects of Bacillus Licheniformis, Bacillus Cohnii and mixed bacteria on compressive strength, ultrasonic pulse velocity test, rapid chloride penetration test, microstructural analysis and bacteria cell concentration of 10 ⁵cell/ml of normal and self-compacting mortars made with and without fly ash for 7 and 28 days. With self-compacting mortar, the compressive strength of Bacillus Licheniformis improved by 30.3 % and by adding Bacillus Cohnii in 28 days, the ion penetration value decreased. Finally, it was observed that the deposition of calcium carbonate in mortar improved compressive strength using SEM-EDS and XRD with compound polymorphisms of calcite, vaterite, quartz, and Hautirite.

Laser-based additive manufacturing (AM) of Ti-6Al-4V has become increasingly important for use in components of transportation devices. The most significant advantage over conventional steel structures is the reduction in specific weight. Complex geometries can be produced with the layer-by-layer manufacturing process and the personalised, unique part production can be faster and produced with the lower costs and less material waste than the conventional manufacturing techniques. Between the manufacturing process of an additively manufactured part and its use, the post-processing is an essential factor related to the strength properties or porosity of the finished product. The heat treatment is a possibility to change the final part properties.

Cam rollers can be used to break up cold asphalt pavements. In Kazakhstan, about 70 % of roads have such coatings. It is most effective to open at temperatures above 20 °C. To reduce the traction force and uniform movement of the roller, it is necessary to eliminate the resistance of the coating to the exit of the cams, when rolling the drum by pivoting the cams in the roller's direction. The reliability of the theoretical studies' results was confirmed by production tests of the cam rollers during the opening of the asphalt concrete pavement on the Gulshad-Akchatau highway.

The paper is focused on fuels, their users - engines and the end-user, the vehicles, from an environmental and economic point of view. The basic characteristics of potential fuels for internal combustion engines, as well as possible sources of electricity, are analysed. A comparative analysis of characteristics of vehicle propulsion with gasoline, diesel fuel, compressed natural gas, liquefied petroleum gas and electricity was performed. The research has shown that the application of vehicles with an electric motor is ecologically justified only in cases of obtaining electricity in an environmentally friendly way and that in other cases there is no profit in an ecological sense. From an economic point of view, if there were no subsidies to manufacturers and buyers of electric cars, they would not be competitive with internal combustion engines now. Within the research, potential solutions for reducing air pollution and improving the quality of life in cities have been proposed.

This study provides a teaching-learning-based optimization (TLBO) path planning method for an autonomous vehicle in a cluttered environment, which takes into account path smoothness and the possibility of collision with nearby obstacles. The path planning problem is tackled as a multiobjective optimization in order to plan an efficient path that allows the vehicle to travel autonomously in crowded settings. The TLBO algorithm is used to find the ideal path, with the goals of finding the shortest path to the target site and maximizing path smoothness, while avoiding obstacles and taking into account the vehicle's dynamic and algebraic properties.

Bike-sharing systems are an important element in development of the smart cities and datasets from these systems are one of the ways to obtain large amount of information on bicycle traffic. These usually contain data on the origin and destination of each trip, as well as its time and duration. Alongside the basic data, some operators also provide information on the exact route picked by each user. This allows researchers to study stopovers, which may serve as a source of interesting information on human behaviour in public spaces and, as a consequence, help improve its analysis and design. However, using the raw data may lead to important errors because most stops occur in the vicinity of bike stations or are related to traffic problems, as evidenced by the case study of Cracow. The data filtering method proposed below opens up the possibility for using such datasets for further research on bike user behaviour and public spaces.

Human factors specifically, perceived behavioural control (PBC) is among the accident causation factors leading to risky driving behaviour among young drivers. Therefore, this paper aims to investigate the relationship between PBC and young drivers' risky driving behaviour, PBC and accident involvement as well as the mediating role of risky driving behaviour to mediate the relationship between the PBC and accident involvement. The sample of this study involved active young drivers aged between 18 and 25, possess valid driving license, with at least six months of driving experience and have been involved in a road accident for the past 12 months. Results showed a significant relationship between PBC and young drivers' risky driving behaviour as well as the PBC and accident involvement. Moreover, risky driving behaviour was proved to mediate the relationship between PBC and accident involvement.

The present study has developed regression models to study the impact of side friction factors on speeds of vehicles in urban roads. The factors that were considered are on-street parking, pedestrian movement, water stagnation, encroachment, poor road condition and wrong side driving. Three locations from Vellore and Chikmagalur cities in India were selected and vehicle speeds, side friction parameters and flow were collected through videographic survey for 6 hours duration. It was found that the speeds of vehicles were in the range of only 11-23 km/h due to side friction. The study has proposed a "simple arithmetic operand" method to overcome the multicollinearity problem and it predicts well, the speeds with mean absolute percentage error (MAPE) between 8-29 %. The arithmetic operand method proposed in the present study can be applied in other fields as well to overcome the multicollinearity problem.

Electric car does not supply all the electric energy, obtained from the electric network, to the wheels in the form of mechanical energy. During such a transformation, a part of this energy is lost. The article endeavours to determine the energy efficiency of selected electric car. The electric car used for measurements is not from the batch production since that is a vehicle designed at University of Zilina. The efficiency has been observed while driving under the conditions of amended methodology of New European Driving Cycle (NEDC). The measured value of electric car's efficiency is being analyzed from the energy consumption, as well as emission production, points of view.

For the developed system of public transport, the passengers, as the customers, have a variety of alternatives when choosing the transport mode or even the route for the given mode of public transport. The estimation of the passengers' preference is the key task for transportation planners for solving the wide range of optimization problems in the field of public transport. A methodology for estimation of the passengers' preference when choosing the bus line within a public transport system is developed in this paper. The proposed approach is based on the fuzzy-logic mathematical apparatus and uses the surveys' data to calculate the membership functions defining the passengers' preference. The case study of the passengers' survey, held in Talas (Kazakhstan), is used to illustrate the developed methodology.

The article presents results of the overpass condition survey, technical survey, static tests and assessment of the structure operational reliability, a double-decker overpass on Almaty-Kapshagai highway section in Kazakhstan.

This paper deals with the noise level of power transformers operating at a middle frequency from 800 Hz to 2000 Hz. The factors that influence the noise produced by power transformers are size, design and operating conditions. The research shows that the noise level of power transformers can vary widely depending on these factors. The paper discusses an overview of different types of power transformers core and their impact on the transformer's noise performance. This paper describes the design of a middle-frequency power transformer, its material composition and the design of the magnetic circuit and windings, operating in the frequency range 800 to 2000 Hz, with a capacity of 200 kVA, air-cooled, to be fed from a suitable frequency converter, characterized by reduced noise. The proposed solution allows implementation of galvanically isolated DC-DC converters for auxiliary traction drives and other DC-DC converters.

The methodology for selecting the main force parameters of nonlinear non-conservative suspension for the main performance characteristics of wheeled vehicles has been developed based on the longitudinal-angular oscillations. The following has been established: a) change limits of static deformation of the elastic suspension system and its other parameters at which the basic operational characteristics for various ranges of amplitude change are satisfied; b) the amplitude of the initial perturbation of oscillations depending on the shape of the inequality and its entry speed; c) the influence of the main characteristics of damping devices on the amplitude-frequency characteristics. The results of this work can be a basis for the choice of such parameters of the considered controlled suspension, which ensure the stability of the vehicle along the curved sections of the road, its controllability, etc.

The COVID-19 pandemic has significantly affected the development of road transport, not only in Poland, but also worldwide. Limited mobility, especially at the beginning of the pandemic, had a large impact on the number of road accidents. The aim of the present study is to predict the number of road accidents in Poland and to assess the impact of the COVID-19 pandemic on variability of the number of road accidents. To attain the objective, annual data on the road accidents for every province in Poland were collected and analysed. Based on historical crash data, obtained from the police, the number of road accidents was forecasted for both pandemic and non-pandemic scenarios. Selected time series models and exponential models were used to forecast the number of accidents.

This paper deals with the use of modern technology for security purposes, focusing on the situation in cities (urban noise and shooting) and in transport (passenger rail). The authors aimed to highlight the possibilities and capabilities of installation of technology in the field of applied physical acoustics (sensors, evaluation system with the possibility of setting sensitive sensing filters, end output) and the possibilities of monitoring, including the response of security forces or security measures to the detected danger. In the paper, the authors also include graphical representations of the energy-normalized spectra of the different sound backgrounds and classification classes of acoustic events and types of acoustic events to clarify the differences of the selected monitored events.

This study discusses the automated visual inspection of electronic boards used in the mass production of power electronics equipment. Soldering splashes, produced during the necessary manufacturing stages, can affect the hybrid power semiconductor modules' quality, specifications and lifespan. Splashes from soldering may appear in some electronic boards areas when they may cause decreasing of quality of these boards and need to be removed. Image analysis algorithms are used to search for such areas. The automated inspection is based on neural network YOLO. The images of electronic boards, acquired by authors in SEMIKRON Slovakia company, were used as training, testing and validation dataset for the YOLO network. The custom recording system was designed to acquire those images. The implementation of this method may increase the object search success and then thereby increase the overall quality of module production.

This paper presents a redundant multi-object detection method for autonomous driving, exploiting a combination of Light Detection and Ranging (LiDAR) and stereocamera sensors to detect different obstacles. These sensors are used for distinct perception pipelines considering a custom hardware/software architecture deployed on a self-driving electric racing vehicle. Consequently, the creation of a local map with respect to the vehicle position enables development of further local trajectory planning algorithms. The LiDAR-based algorithm exploits segmentation of point clouds for the ground filtering and obstacle detection. The stereocamera-based perception pipeline is based on a Single Shot Detector using a deep learning neural network. The presented algorithm is experimentally validated on the instrumented vehicle during different driving maneuvers.

In this paper is given the definition of e reliability of a transport information system, with features of transport information systems listed. Equations for calculating reliability indicators are given, as well. The developed hierarchical graph model for assessing the reliability of transport information systems and an algorithm for analyzing the graph model, which allows taking into account the specifics of the reliability of the operation of system elements at different levels of the hierarchy, are presented. Using the graph model and the graph model analysis algorithm, it is possible to reasonably predict the strategy for the creation and development of transport information systems.

The article deals with the problem of estimating the rational number and utilization rate of the vehicles' fleet. According to the analysis results of the state-of-the-art literature it has been revealed that the issue of substantiating the rational fleet size and the rate of its utilization were not fully solved. The purpose of the study was to increase the efficiency of servicing transportation orders by determining the required number of vehicles. The goal of the research was the influence of the transportation process parameters on the truck utilization rate. Originating from the probabilistic nature of the transportation process, it has been proposed to use the AnyLogic software product to develop a simulation model for vehicle orders' servicing. From the processing of the experimental results by the regression analysis methods, it has been found that the dependence of changes in the vehicle utilization rate is of a linear form.

Models developed in Highway Capacity Manual (HCM) are not suitable to cater to the effects of mixed traffic conditions and hence, its use is unjustifiable. This research investigates such a challenging problem as the effect of undesignated pedestrian crossings on the entry capacity of roundabouts. For the present study, field survey data were collected using video cameras from three roundabouts such that the base section (roundabout without pedestrian influence) and non-base sections (with pedestrian influence), both scenarios, were captured. A modified HCM equation was developed to estimate entry capacity and further, the reduction in capacity with respect to pedestrian volume is determined. Lastly, a relationship was developed to check the effect of pedestrian crossflow on the entry capacity. The relation shows that capacity reduced to 1841 Passenger Car Unit (PCU/h) when the pedestrian flow increased to 288 pedestrians/hour.

In this paper, the authors discuss the method of deformations compensation (resulting from the impact of variable temperatures and pressure) in pipelines intended for fluids transport (liquids and gases). Classical methods of compensation through the so-called "natural compensation" and using special devices called expansion joints. In this paper authors present research work on a new type of the metal expansion joints, called bellow-lens expansion joints. The mechanically assisted laser forming method, which was used to manufacture the bellow-lens expansion joints, was presented. The method uses CO₂ laser radiation to heat the element from which the expansion joint will be made and the proprietary system consists of an actuator and swivel handle.

One of the most important directions of intensification and increasing the efficiency of the transportation process is to improve the use of the carrying capacity and capacity of vehicles. For this, it is necessary to the choose rational schemes for loading the cargo into cargo places of the rolling stock. The possible options for loading the vehicle body with cylindrical loads, which are transported when they are installed on the end, are considered. The conducted analysis showed that there are several typical schemes for loading such cargoes. Analytical dependencies have been obtained that allow choosing a rational loading scheme when transporting such cylindrical loads, considering their parameters and the characteristics of cargo places of vehicles. Based on the performed research, the best variant is proposed, i.e. the option with the clearance of 0.2 m, allowing transportation of 125 cylindrical cargo units in the space of a vehicle.

The paper aims to present an analysis of the component sizes of commercially available vehicles with electrified powertrains. The paper provides insight into how the powertrain components (an internal combustion engine, an electric motor and a battery) of mass production electrified vehicles are sized. The data of wide range of mass production electrified vehicles are collected and analyzed. Firstly, the main requirements to performance of a vehicle are described. The power values to meet the main performance requirements are calculated and compared to the real vehicle data. Based on the calculated values of the power requirements the minimum sizes of the powertrain components are derived. The paper highlights how the sizing methodologies, described in the research literature, are implemented in sizing the powertrain of the commercially available electrified vehicles.