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This study employs the grey models to explore Nigeria’s road transport energy consumption, vehicle population and vehicular emissions. The vehicular emissions were evaluated using the European Environment Agency Tier 1 Approach, based on the fuel consumption. A baseline scenario, based on historical data and three other alternative scenarios were developed. The study considered fuel quality, vehicle technology and survival rates as the key drivers of scenario formulation. Results show that vehicle population increases by about 3.58 % annually from 12.9 million units in 2018 to 38.5 million in 2050. Analysis of the alternative pathways reveals that their adoption would significantly reduce road transport energy consumption and air pollutant emissions.

The results of the analysis of sand application efficiency for improving wheel-rail adhesion are presented. An algorithm for the sandbox operation is substantiated, based on supplying sand under the wheels when their slip reaches a critical level, delivering sand in proportion to the vehicle speed, and automatically purging the sand supply pipes. The principle of sandbox operation is based on the mechanical interaction between the moving elements and sand. It has been established that the maximum adhesion coefficient is achieved when the sand is evenly distributed in a single layer within the wheel-rail contact area. The important role of the contact area in the wheel-rail adhesion is emphasized. A sandbox implementing the developed sand supply algorithm is proposed. The introduction of this sandbox on Ukrainian-manufactured trams is described.

The impact of using three contents of 1, 3 and 5 % of nano CaCO3 on the composition of asphalt binder and the mechanical properties of Hot Mix Asphalt (HMA) wearing course was studied. Laboratory tests were performed to examine the physical and rheological characteristics of nanomodified asphalt binder. In addition, Superpave Indirect Tensile Test (IDT) was conducted to evaluate the mechanistic characteristics and moisture susceptibility of the HMA. The test findings pointed that the nano modified asphalt with 5% nano CaCO₃, decreased the temperature sensitivity due to asphalt stiffening and improved resistance to permanent deformation. Additionally, HMA mixture performance exhibits a substantial increase in moduli value at temperatures varying from 5 to 40 ^oC and increased flexibility at lower testing temperatures as compared to the neat HMA mixture.

To address the challenges of dynamic routing in the last-mile transport logistics, an adaptive method has been developed for solving a multi-criteria dynamic vehicle routing problem with static time windows, taking into account the actual configuration of the urban road network and the non-stationary traffic dynamics on its sections. At the same time, the method enables the use of consolidated real-time data on the dynamic characteristics of traffic flow on sections of the transport network from any sources available at the time of optimization (e.g., GIS, road sensors, mobile devices, etc.). The results of simulation studies using the ant colony optimization method indicate the promising potential of the proposed approach.

In this study was investigated the Technical Readiness Coefficient (TRC) of railway rolling stock and associated technical systems. The primary objective was to identify and analyze the key factors influencing TRC and to develop a structured methodology for the factor analysis of railway technical readiness. The research methodology includes the selection of principal determinants, construction of a descriptive analytical model, processing of empirical operational data, and application of regression and correlation analyses. Empirical and theoretical approaches were employed, using statistical data, maintenance schedules, normative tables, and computational tools. Findings can be used for monitoring the TRC, optimizing maintenance and modernization, improving operational efficiency, and supporting evidence-based management decisions. The methodology also provides a framework for evaluating the future railway systems and ensuring continuous monitoring of technical performance under operational conditions.

The scientific task of the nozzle scheme uses for formation of an air cushion by using the energy of a jet of air supplied under pressure, simultaneously to form an air cushion, as well as to create the driving force of a load-bearing web, was formulated and the main idea of the work was defined. The optimal option to significantly increase the productivity and length of special types of conveyors is to use the energy of a jet of air supplied under pressure simultaneously as an air cushion and as the driving force of the load-carrying body, which makes it possible to sharply reduce the coefficient of resistance to movement of the load-carrying body and improve its operating conditions. Supporting the load-carrying body with an air cushion allows to increase the speed of movement to 8 to 9 m/s and more, increase the reliability and safety of conveyor operation, and protect the environment.

The research object is a pneumatic spring of the second stage of spring suspension of the high-speed railway rolling stock in movement conditions by a switch. Full-scale dynamic tests of a pneumatic spring for the high-speed railroad rolling stock were carried out. It was found that the average values of vertical accelerations in the trailing and facing directions in the wind turbines moving by the switch are 1.307 m.s^-2 and 1.279 m.s^-2, respectively. The ratio of the average values of longitudinal accelerations in the trailing and facing directions within the wind turbines is 1.01, and at the wind turbine bases is 2.15. It is found that the average value of the first natural frequency of oscillations of the pneumatic spring is 3.53 Hz, while the logarithmic decrement of the oscillation attenuation is 0.321.

A method for online dynamic routing of freight delivery under limited traffic information using an ant colony algorithm, has been proposed. This method leverages real-time IoT data on traffic flow (TF) intensity from traffic sensors on urban road network (URN) sections, combined with averaged historical data on TF parameters (speed, density, intensity) obtained from traffic sensors on representative sections of homogeneous clusters within the URN. The procedure for forming homogeneous clusters within the URN and identifying representative sections is described. The results of simulation studies using the URN of Kyiv as an example indicate the potential of this method for urban transport logistics in conditions of complex traffic.

In this paper are summarized the results of measurements of the driving characteristics of fire-fighting vehicles during the braking from high speeds. Two water tender vehicles manufactured by TATRA, used by the Fire Rescue Service of the Czech Republic, were compared. The tested vehicles differ in their braking systems. In the study are monitored the braking distance and deceleration, which were compared with previous tests focusing on tire type, test track surface, and weather conditions. When braking from a speed of 80 km/h, the worst results of the braking distance were recorded for SCANIA of 64 m and TATRA TerrNo1 (9T5 2243), of 73 m. These vehicles were equipped with drum brakes. In the case of the SCANIA vehicle, the cause was the heating of the drum brakes. For the TATRA TerrNo1, the reduced braking efficiency was likely due to the brake wear and thermal effects on the drum brakes.

The article highlights the results of the traffic safety analysis conducted in the wagon industry of Ukrainian Railways. Based on this study, it was found that the largest number of transport accidents are caused by the braking equipment of wagons. The study is based on the statistical data on malfunctions of the mechanical part of the brake equipment of bogies, in particular, those caused by the wear of wagon brake pads. The results obtained were arranged and processed in the data analysis and visualization program STATISTIKA.
Using a systemic approach, the structural, technological and operational factors that affect the reliability and efficiency of the brake system of bogies and the wagon safety were classified. The research could contribute to increase the efficiency of the railway transport operation and maintenance of its position in the spectrum of the transportation process.

In this article is presented a new method of ultrasonic cleaning of exhaust gases of diesel engines by coagulation of soot particles and their subsequent sedimentation. The analytical modelling of the particle motion in a vertical muffler stand was carried out, taking into account the ultrasonic effect and gravitational forces. Experimental studies of the developed stand confirmed that ultrasound promotes agglomeration and sedimentation of soot, reduces the CO₂ content and increases the O₂ concentration in the exhaust gases. The maximum cleaning efficiency is achieved with the simultaneous use of all the ultrasonic emitters. The results of the work can be used in designing modern exhaust gas cleaning systems.

Given the shortage of petroleum bitumen in the Republic of Kazakhstan, the use of local bitumen-containing rocks is becoming increasingly relevant, which requires the development of specialized mechanization tools. In this paper are discussed the special excavator buckets designed for year-round extraction of rocks with a bitumen content of up to 25%. The design features of the bucket that reduce resistance during digging and unloading are described. Calculations of resistance, chip thickness, operation duration, and productivity of the EO-4121 excavator at different temperatures and bitumen contents were performed. It is shown that unloading becomes more difficult when the bitumen content exceeds 18.2%. A comparison of the calculated and experimental data confirmed the high accuracy of the models used.

Stream speed pattern of traffic plays a crucial role in urban transportation. The presence of on-street parking significantly reduces this speed by narrowing the carriageway width available for traffic movement, impeding the traffic flow. Therefore, understanding the traffic flow behavior in the context of on-street parking could be challenging. In this context, the present study explores the influence of on-street parking on the stream speed of regular traffic. To achieve this, data were collected at various ideal and parking sections. The stream speed ranges from 39.28 km/h to 51.47 km/h for ideal sections with significant percentage reduction observed at parking sections, ranging from 39.09% to 81.30%. This speed reduction was then modelled considering the most significant parking parameters conceptualized in this study. The findings of the study offer valuable insights that can be implemented for developing the on-street parking norms.

The pedestrian behavior at five signalized crosswalks in Kielce, was analyzed in this study with a particular focus on the increasing use of mobile phones and other electronic devices while crossing the street. Compared to previous ITS studies, which showed that 7% of pedestrians used phones, the current study reveals a significant increase in this phenomenon, with percentages ranging from 14 to 60%. The highest levels of phone usage and risky behaviors were observed at the intersection of Aleja Solidarnosci and Swietokrzyska Street. The results also indicate a decrease in the number of cases of crossing on a red light but an increase in the number of pedestrians crossing during the flashing green signal. The study results point to the need for targeted educational campaigns and the adaptation of infrastructure to address the new challenges associated with mobile device use by pedestrians.

The introduction of bus lanes on streets may not be feasible from the standpoint of reducing the overall time loss for road users. The goal of this study was to develop a method for checking the effectiveness of bus lane implementation. Using simulation experiments, conducted in PTV VISSIM, for a different number of traffic lanes, the speeds of buses and vehicles were determined both when buses are moving in the general flow and after the introduction of a bus lane, at different values of flow intensity and bus frequency. Regression equations, describing the dependence of speed on the traffic flow intensity and frequency of buses for different numbers of traffic lanes, are formulated. A mathematical model has been developed to calculate and compare the time losses of road users before and after the introduction of a bus lane, based on determining the average speed of traffic flow and buses.

Despite the significant research on the seismic stability of earth structures, critical gaps remain in understanding the dynamic response of soil slopes with varying reinforcements. These gaps were addressed in this study by using a small shake table to investigate the dynamic behavior of soil slopes under different conditions. The research examines responses at various frequencies, the effect of reinforcement methods, and the impact of slope height. Results indicate that the higher frequencies and amplitudes lead to increased displacements, while reinforcement reduces crest displacement by 21 to 45%. Steeper slopes (35° and 40°) also show increased displacements by 9 to 65%, compared to a 30° slope. The importance of reinforcement in improving the seismic resilience of soil slopes is highlighted in this study, offering practical insights for engineering design.

In this paper is presented platooning as a promising approach to reduce the greenhouse gas emissions, fuel consumption, and operation costs in heavy traffic. Attention is given to a risk assessment of vehicle-to-vehicle (V2V) communication in the context of ISO 26262, Edition 2: Road vehicles - Functional safety. [ISO 26262-2 2018] The analysis focuses on safety-related hazards associated with convoy driving of heavy vehicles, utilizing the principles of functional safety. It applies hazard analysis and risk assessment (HARA) to classify potential risks according to their severity, exposure, and controllability. Automotive safety integrity level (ASIL) is later determined for each risk. The results provide the ASIL levels of identified hazards, which can be used for developing and validating functional safety measures for cooperative truck driving.

Cognitive radio (CR) technology enables dynamic spectrum access to meet the growing demand for wireless communication. This study investigates spectrum sensing methods, specifically energy detection (ED) and matched filter detection (MFD), within hybrid strategies. A novel hybrid MFD method was developed and evaluated via MATLAB simulations, analyzing factors like sample size, signal-to-noise ratio (SNR), and false alarm probability. Results reveal that ED has a higher miss-detection rate compared to MFD and the proposed hybrid method, which performs particularly well under low sample counts and SNR conditions. This research enhances spectrum sensing techniques in cognitive radio systems, paving the way for more reliable wireless communication networks.

The research is aimed at solving the problem of traffic congestion during the underground repair work in cities. The goal is to develop and analyze a modular mobile overpass that ensures continuous traffic without bypassing repair areas. The stress-strain state of the spatial steel frame of the orthogonal overpass module was studied using analytical methods of structural mechanics - the displacement method and the force method. Critical forces are determined, relationships between bending moments and stiffness of elements are revealed, optimal parameters ensuring strength and stability of structure are determined. The results confirm the feasibility of the mobile overpass as an effective engineering solution to reduce the transport delays and environmental load, forming the basis for the design of next-generation mobile bridge systems.

In this article are discussed the features of selecting the geometric parameters and calculating the strength of the horizontal lever in the brake lever transmission of a freight wagon bogie. The results of the research show that the greatest stresses are concentrated in the areas where the holes for the rollers are located. Since the design stresses are 22% lower than the permissible value, thus the strength of the horizontal lever is obeyed. This research results could be useful in the design of modern brake lever transmission systems.

The optimization of gear pairs in a two-stage planetary gearbox was performed using the Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). A total of 18 combinations of input parameters were analyzed, varying: gear width (20, 22, 24 mm), module (2.25, 2.5, 2.75 mm) and material (16MnCr5, 34CrNiMo6). Safety factor from pitting (Sh) and safety factor from tooth fracture (Sf) were numerically obtained and those two parameters were chosen as criteria for optimization. TOPSIS identified alternative 1 (20 mm width, 2.25 mm module, 16MnCr5 material) as the optimal solution, demonstrating the highest safety factor values. Additionally, the optimization achieved satisfactory results regarding the mass of gear pairs. After optimization, the mass of gear pairs decreased by 20% compared to the pre-optimization version.

The development and simulation of a mathematical model for a hybrid powertrain vehicle, aiming to optimize its energy efficiency and dynamic performance is presented in this study. Implemented in MATLAB/Simulink, the model captures the dynamic interactions between the hybrid system's components, including the internal combustion engine, electric motor, and battery. By conducting a full factorial experiment, the specific power of the hybrid vehicle was analyzed, revealing the critical influence of factors such as driving speed, road gradient, and battery state of charge. The proposed model demonstrated a discrepancy of 4-11% between the simulated and experimental results, confirming its adequacy for forecasting energy consumption and operational range. These findings offer valuable insights for enhancing the hybrid vehicle performance and sustainability through precise energy management strategies.

In this study is examined the influence of traffic flow parameters on delay duration at signalized intersections of urban multi-lane streets. The findings show that traffic composition strongly affects delays at low volumes, while its influence decreases as total volume grows. These results highlight the need to account for traffic composition, not only volume, when optimizing the signal timing and managing flows. The novelty of the study lies in modelling delay as a joint function of traffic volume and traffic flow composition, where the share of passenger cars is varied independently, rather than through the generalized passenger car unit-based growth, enabling a more accurate assessment of delay formation under heterogeneous traffic conditions.

Rough roads negatively affect the ride quality and energy efficiency of autonomous vehicles (AVs) and demand adaptive speed control. To solve this, this research proposes a Deep Capsule Network integrated with Sparse Kernel K-means Clustering (DCapsNet + SK-K-means) to accurately reconstruct pavement conditions and adapt vehicle speed in real time. The Privacy-Preserving Federated Learning (PPFL) with Hyperledger Fabric blockchain allows federated learning to be trained in a secure and decentralized manner without the transfer of raw sensor data. With the BDD100K dataset, supervised and reinforcement learning are used. According to the obtained results of the experiment, there is a 10.45% increase in ride comfort, 28.23% in energy efficiency, and 98.28% in computational efficiency. The framework attains 93.73% security, 96.46% throughput and 0.83 s operation time at 250 vehicles/km.

Household car ownership has become a crucial issue in Indonesia due to rapid urbanization and economic growth, which have led to increased demand for personal vehicles. This surge in vehicles contributes to traffic congestion, pollution, and strains on urban infrastructure. This study aimed to investigate private vehicle ownership in relation to household characteristics and mobility attributes in developing country settings. The methodology used is the multinomial logit model (MNL) to analyze ownership patterns. The empirical results showed the significant impact of the income variable on vehicle ownership. Ownership of multiple private vehicles was more prevalent among individuals with a driver's license, males, and those who traveled longer distances. These outcomes could be invaluable for policymakers focused on reducing auto dependency and enhancing the efficiency of urban transportation systems.

The purchasing behavior of the population affects both passenger and freight traffic in cities. On the contrary, indicators of purchasing behavior are influenced by the characteristics of an individual, as well as external factors. The purpose of the conducted research was to analyze the population's purchasing behavior under martial law conditions. Data was collected by surveying residents of Ukraine's rear regions. Multinomial models of the frequency of purchases and transportation choice during shopping were formed. Martial law conditions and changes in the population size in the rear regions, change the general trends in purchasing behavior. The most visible trends are: a significant share of purchases made online, the popularity of shopping close to home, and the tangible impact of owning a car on the frequency and mode of shopping trips. The results obtained may be helpful in predicting consumer behavior in crisis scenarios.

Biomass combustion is a widely used renewable option for a small-scale heat and power, but incomplete burnout and pollutant formation remain challenges in boilers without optimized air staging. In this study, is investigated how controlled transport of air into the flame zone, implemented with an auxiliary tertiary system, affects performance and emissions in a bottom-fed pellet boiler. Tests were performed at constant fuel feed and primary/secondary airflow, with tertiary air varied between 0 and 15.8 m3/h. An airflow of about 8.9 m3/h proved optimal, giving the highest thermal output, a more uniform temperature distribution, and a nearly twentyfold reduction in CO emissions normalized to 10% O2. NOx rose only moderately (by approximately 60 mg/m3). The findings show that targeted air transport and staging into the flame zone can substantially improve combustion completeness and boiler efficiency.

The research presented in this article is aimed to show the prospective direction of increasing the efficiency of cleaning dusty air flows from light impurities and dust on mobile grain separators by using a rotary cyclone with a multi-disc after cleaner. An increase in the efficiency of the process of cleaning the dusty air flow in dust collectors is provided by an additional effect on dispersed particles for their intensive redistribution in the working areas. The developed rotary cyclone has two working zones: the main zone and the post-cleaning zone. The rotary cyclone consists of a bladed impeller, a main cylindrical channel, a sedimentation chamber and an after-cleaner. The overall air flow purification coefficient of the rotary cyclone varies between 87.5 to 92.5 %.

The development of a country's economy largely depends on the pace and efficiency of construction work, which, in turn, is determined by the extent to which innovative technologies and techniques are used. This work is devoted to justification of the basic parameters and the development of a new working body for a machine for cutting joints in road surfaces. A design with cycloidal motion is proposed, which intensifies the destruction process due to the vibrational impact of the cutters on the material being processed. The use of such a working body provides a vibrational effect, increases the cutting speed, and reduces the energy consumption of the process. As a result of intensifying the interaction between the working body and the material, it was possible to reduce the energy consumption of cutting by 1.13 times, and increase productivity by 1.18 times compared to analogues.

The dependence has been obtained that links the degree of coagulation of soot particles, the parameters of the ultrasonic equipment, the geometric dimensions of the ultrasonic muffler, the frequency characteristics of ultrasound, and the parameters of the engine operating mode. In the paper is presented solving of a problem of determining the number of particles in 1 cm³ of exhaust gas depending on the smoke index. An example of calculating the required ultrasound power for a full-size ultrasonic vehicle muffler bench has been given.