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The article shows a fragment of the results of the author's concept of road safety management in Poland. The article shows the "program sequence" of the construction action of road safety management system in Poland. The main component of this "sequence" of actions to improve the road safety - should be the "road risk management model". It should be widely used in Poland as an element of knowledge and practices of international road safety management. It is primarily about the model of the Office for Land Transport Safety Authority in New Zealand adopted by the EU in its road safety policy. The article also presents other components of the author's concept, including the "3 levels" model of risk management, the idea of which is to isolate three categories of the risk associated with any transport system.

The 33.0 m long reinforced concrete bridge beams of the overpass superstructure after vehicular impacts were taken as a research object.
The overpass consists of 14 beams, six of which were repaired by restoring the widened lower part with EMACO FAST TIXO, manufactured by BASF.
The remaining 8 beams were completely dismantled and replaced with new ones. The new beams have been fully tested for the perception of vehicular loads. The fully reconstructed span structure showed compliance with the design loads of A14, NK-120 and NK-180 based on test results.

The main objective of our research was to map the exposure to electromagnetic smog in the frequented space of shopping centres in the city of Bratislava and to compare our results to the actual hygienic limits. The measurements of the low- and high-frequency electromagnetic fields were performed at different places in shopping centres. Our results did not exceed the Slovak current limits in any of the measurements. However, almost all of them markedly exceed new permitted limits according to EUROPAEM. Based on our results, stricter limits in many European countries and increasing evidence on possible harmfulness of long-term exposures to artificial electromagnetic fields, preventive carefulness can be recommended - to support the research in this field, to prepare professional public education and possibly to prepare the stricter Slovak exposure limits.

The aim of this research was to find out the specific geometrical parameters of the harmonic drive with the greatest impact on its lost motion. Harmonic drive units are widely used in production automation, robotics and automated manufacturing systems. Virtual model of Harmonic Drive was examined using the finite element method. The analyses were performed with considering the real test conditions of high precision gearboxes with a lost motion value of 4 % of the nominal output torque. The analyses' results were then used to develop a unique approach to obtain a functional relationship between the input parameters defining the shape of the flexspline and the harmonic drive lost motion value. Subsequently, the global sensitivity analysis was performed to determine the degree of influence of the selected flexspline parameters on the harmonic drive kinematic accuracy.

This study focuses on the issue of choosing a means of transport on the PilaWarsaw route by four groups of recipients. Representative sample consists of a student, a family with two children, a business client and a pensioner. The choice of the means of transport depends on various criteria resulting from the preferences of the users of the means of transport. The following criteria emerged from the survey results as a priority: transport time, transport cost, comfort and safety of travel, availability of means of transport, necessity or absence of transfers, cost of luggage transport and punctuality of means of transport. Selected preferences were assigned weightings based on the evaluation of a panel of experts in the field of expertise. In order to select the means of transport to implement the transport task, multi-criteria optimization method was used.

Present study evaluates the various congestion indexes in terms of speed performance index, volume to capacity ratio and congestion index based on travel time on the urban roadway network of 5.7 km in length, operating with mixed traffic conditions (traffic with varying static and dynamic characteristics of vehicles). The mitigations measures have been proposed to cater to the present traffic demand by converting the uncontrolled intersection to a partially controlled or signal-controlled intersection. In order to check the effectiveness of such mitigation measures, various scenarios have been generated in the developed and a well calibrated simulation model. It has also been observed that the speed performance index has improved by 8.88 percent while providing channelized intersection at one of the point elements and 11.52 %when the two-point elements have converted to channelizing intersection.

The article deals with the existing methods of cleaning vehicle radiators from sedimentary scale. A method of cleaning radiator tubes by ultrasonic radiation is proposed. An experimental bench has been developed for studying ultrasonic cleaning processes. Based on the results of the experiment, dependences have been obtained that determine the efficiency of the process depending on the mass of scale removed and the liquid outflow rate from the tubes. There are proposed the purification degree coefficients. The hypothesis about the possibility of cleaning radiators with ultrasonic vibrations has been confirmed.

The attractiveness of public transport is not high and therefore it is obvious that private transport is the preferred mode of transport. The interest in public transport has declined even more since the outbreak of the COVID-19 pandemic, during which passengers feared the rapid spread of the disease in public vehicles. As a result, the habit of traveling individually has increased. This paper highlights the massive increase in private transport in the V4 Countries by the use of private vehicles and the related decrease in use of public transport. It also presents some of the relevant tools of the Smart City concept that could improve the use of public transport in cities. This paper is aimed at highlighting the current use of public bus transport (including public transport) in the V4 countries vis-a-vis the ongoing COVID-19 pandemic and highlighting the information and communication technology (ICT) - related means of incentivization.

Pedestrian fatality rate plays a key role in examining effectiveness of the road safety. The present study attempts to examine the effect of various categories of accused vehicles and the average 85^th percentile speed at accident location on the pedestrian crash fatality. The study also attempts to develop pedestrian crash severity models using the binary logistic regression and boosted trees technique. Historical crash data, along with the video recording technique at accident sites, have been utilized for the present study. From regression equations, it is observed that when the heavy vehicle (HV) hits a pedestrian as compared to two-wheeler (2W), the average chance of death increases 2.44 times. According to the Boosted tree model, the contribution of speed is 60 %, whereas the contribution of category of accused vehicle is 40 % for pedestrian fatality prediction. The study should help in planning better strategies like all red time at intersections or pedestrian foot over bridge at critical locations.

Current crisis management approaches to protect soft targets make assumptions about average visitors/listeners/viewers or passengers. They do not give much consideration to impacts of diversity of potentially evacuated persons with regard to socio-psychological parameters/factors that may lead to practical problems and complications during the evacuation itself. At the same time, the soft target operators have various means of machine vision tools at their disposal, but do not use these records for more thorough analysis of evacuation planning needs. Based on this observation, the article identifies and analyzes the socio-psychological aspects that may significantly affect behavior and decisions of persons during the evacuation and thus total evacuation time.

The purpose of this paper was to determine the usability of unmanned hydrographic drones and photogrammetric techniques during the conduct of work, the results of which are potentially to serve as navigational materials in areas that, due to their characteristics, make it impossible to carry out research using crew vessels and direct shoreline determination. In order to prepare and carry out the measurement campaign with the greatest possible accuracy and safety, the authors of the article decided to determine the shoreline of the analyzed reservoir using photogrammetric methods. The use of satellite images allowed the border between land and water to be identified as precisely as possible, which had a direct impact on the accuracy of relating depth data to their location on Earth's globe. Use of unmanned vessels and orthophotos can find practical application when navigating vessels during maneuvers required high precision.

Every year, there are more and more cars on the roads that cause pollution. To reduce it, conventional vehicles have started to be replaced by electric and hybrid vehicles. Therefore, the average fuel/energy consumption of electric, hybrid, spark ignition and self-ignition vehicles over a test distance of 100 km was investigated. The test results were then compared to the manufacturer's data and the average difference between the manufacturer's data and the test data is shown. The largest average difference in fuel consumption between the manufacturer's data and the test data was observed for hybrid vehicles (over 230 %) and the smallest for electric vehicles (less than 10 %) and spark ignition vehicles (almost 18 %). Considering costs, the largest difference between manufacturer's data and test data is observed, as in the previous case, in electric vehicles (0.25 €) and the largest in hybrid vehicles (almost 6 € per 100 kilometers driven).

In the last decades, the Italian road transport system has been characterized by severe and consistent traffic congestion and in particular Rome is one of the Italian cities most affected by this problem. In this study, a Levenberg-Marquardt (LM) artificial neural network heuristic model was used to predict the traffic flow of non-autonomous vehicles. Traffic datasets were collected using both inductive loop detectors and video cameras as acquisition systems and selecting some parameters including vehicle speed, time of day, traffic volume and number of vehicles. The model showed a training, test and regression value (R²) of 0.99892, 0.99615 and 0.99714 respectively. The results of this research add to the growing body of literature on traffic flow modelling and help urban planners and traffic managers in terms of the traffic control and the provision of convenient travel routes for pedestrians and motorists.

Concrete belongs to the most used building materials, applied in almost all types of constructions (civil, industrial, road, hydraulic, subway constructions, etc.). Currently, the most common is the vibration method of molding concrete and reinforced concrete products.

The long-distance travel (LDT) mode choice modeling is important for transportation planners. This study investigated alternative mode choice behavior for the LDT between the intercity buses and trains. A questionnaire survey, consisting of important mode choice attributes, was conducted on various groups of people in Bangladesh. Numerous travel mode choice contributing features (e.g., travel time, travel costs, origin-destination, comfort, safety, travel time reliability, ticket availability and schedule flexibility) were considered and the LDT mode choice models were developed using various machine learning algorithms typically applied for classification problems. With 95.31 % accuracy and 0.95 F1-score, Random Forest model was the best performing model for the dataset. According to the findings of this study, the intercity bus is preferred over the intercity train for LDT in Bangladesh.

The advantages and disadvantages of using the soft containers for cargo transportation are analyzed. The issues of the use of soft containers in transport and technological schemes for the supply of bulk goods are considered. Approaches to the rational selection of parameters of soft containers, during the transportation of bulk cargoes, taking into account the characteristics of the transported cargoes, are defined.

The term "Creative City" emerged in the 90s of the 20th century reflecting the trend of transforming post-industrial cities into new creative urban centres - bases for knowledge intensive firms, highly-skilled workers and major cultural assets. The concept of culture-based urban regeneration describes a scheme where culture is purposely employed as a vehicle for an overall urban and social revitalization. The paper addresses innovative processes within culture-based urban regeneration projects in three Slovak cities - Bratislava, Zilina and Kosice - under the concept of creative city. The focus is on the implementation of a tailor-made multi-factor knowledge management model with the aim of exploring the knowledge management practices in urban development projects dealing with the adaptive re-use of industrial and cultural heritage based on the non-profit bottom-up initiatives.

Roundabouts have proven to be an effective intersection design method for smooth traffic flow movements and improved safety. Previous studies show that VISSIM, commercial traffic simulation software, can be used as a proficient tool for modeling and efficiently analyzing roundabouts. This paper focuses on developing a methodology for modeling roundabouts in India using VISSIM. Three typical roundabouts were chosen from the northern part of India. Calibration and validation of the model were performed to ensure the correctness of the model. The average delay and volume to capacity ratio (v/c ratio) were compared for developing the level of service (LOS) thresholds for Indian conditions. The thresholds are compared with existing guidelines provided by the HCM 2010 and AUSTROADS. In addition, the methodology for determining modification factors for applying HCM 2010 delay model in Indian traffic conditions is defined.

This work experimentally investigates the most imperative parameters that control the injection and combustion processes in a multi-injection HCCI Diesel engine namely; fuel-line pressure, timing of multi-injection events and the resulting in-cylinder pressure. These parameters in addition to the heat release rates are evaluated at different engine loads and speeds over up to 42 successive cycles. The main inter-relations of these parameters are also discussed.

The presented article aims at assessment of the influence of test bench design on the cooling performance of a rail vehicle brake disc. The test bench is designed for experimental analyses of rail vehicles' brake components. The work includes an introduction to the solved problem, as well as a description of importance of airflow simulations in virtual environment. Creation of a geometrical model and its most important features are described. The research is performed by means of the computational fluid dynamics. For this method, it is important to set-up the boundary conditions, which are presented in the next part of the article. The results of the computational fluid dynamics simulations are presented for the solid disc and for the ventilated disc. The simulations of the solid disc showed the better convergence of calculations for various time-steps in comparison to the ventilated disc.

Traffic congestion is a major problem around the globe. The prime reason for congestion is unavailability of traffic infrastructure to meet the traffic demand. Road users are forced to face undesirable delay, which influences the economy, environment and health. The present study examines the congestion in the urban roads of Bhubaneswar, a smart city in India. Travel time for various categories of vehicles was estimated and congestion indices in terms of buffer index were evaluated. Multiple linear regression modeling has been used to evaluate the congestion parameters. The p-value for all the independent variables in the developed model is < 0.05. Four elements, namely Strict traffic law implementation, Adequate parking facilities, Decentralization and Controlling the road side activities are required to improve the serviceability and mobility of urban road networks.

Additive manufacturing provides the possibility to print complex generative designed bodies. The research deals with redesigning a payload part of a camera holder using generative design for selective laser melting. The possibility of replacing the original polymer component with a metal printed component of a greater strength and the effect of different parameters of generative design were investigated. By comparing the generative design results obtained in several phases, the goal was to find a solution that can be used to replace the previous part and become printable with 3D metal printing. The internal stress values for each case and the amount of weight reduction that can be achieved were determined. With the results obtained, the parts were prepared for printing. It is the key aspect of the industrial application of generative optimization.

The work presents the results of a statistical analysis of random processes of the coefficient of vertical dynamics of a passenger car variation. To determine the dynamic performance of cars the tests were running on the tracks of JSC "Ukrzaliznytsia". The main statistical characteristics of random processes are determined for various modes of car movement along curved and straight sections of the track. As a result of statistical processing of experimental data, correlation functions have been constructed that characterize the degree of connection between different time sections of the process of changing the coefficient of vertical dynamics. The obtained indicators of the law of distribution of the vertical dynamics coefficient values, approximating the models of correlation functions and the numerical values of their parameters, make it possible to further simulate the process of loading a passenger car without carrying out lengthy expensive tests.

The purpose of the proposed study was to identify the functional patterns of influence of the marketing tools on sales of cars on the global market, to be able to predict sales volumes in the future, taking into account certain marketing tools that the company may use in a particular international market. For the purpose of this research the method of correlationregression analysis is used to construct the corresponding economic and mathematical models of impact on the sales volumes of various instruments of product, price, promotion policy, etc. Using the models offered in the article, the feasibility of introducing certain measures can be determined, when entering new markets in order to increase car sales. Each instrument to which potential buyers are sensitive determines the effect of its use. Considering this effect, budgets can be set up for appropriate action.

Carbon and pollutant emissions drive climate change and affect health and daily life. The Covid-19 pandemic created an unprecedented opportunity to understanding the impact of carbon and pollutant emission. In this paper were identified Telecommunications records-derived general mobility indices as contributors to the PM10 pollutant concentration development in industry-intensive Sisak-Moslavina County, Croatia, during the Covid-19 outbreak in 2020. Time-series of daily mean PM10 concentrations and mobility changes indicators are analysed for their statistical properties identification, decomposed, and the decomposing components examined for association using Tailored software developed in the R environment for statistical computing.

The article presents a search for links between the Periodic Technical Inspections of Vehicles (TI) and traffic accidents due to vehicle technical defects in the Slovak Republic. Based on these links, it is sought to assess the justification for TI regarding the road safety. For this purpose, statistical data on traffic accidents, caused by vehicle technical defects as well as data concerning TI carried out were examined. The first finding was that the approaching end of the validity of the TI, the probability of traffic accidents due to technical defects increases for vehicles. The second finding was that with the increasing number of vehicles assessed at the Periodical Technical Inspection Stations (PTI) as temporarily roadworthy and not roadworthy, the number of accidents due to vehicle technical defects was decreasing. The results formulated in this paper show that the TI have a measurable effect on traffic accidents caused by vehicle technical defects, thus positively affecting the road safety and thus having a demonstrable justification.

Because the numbers of cars reflect each person's travel behaviors for each specific location, the car ownership demand model plays a dominant role in analysis of the travel demand in order to understand each area's individual and household travel behaviors. However, the study project for the master plan of the Khon Kaen expressway represented imbalanced data; namely, the majority class and the minority class were not equal. Before developing a machine learning model, this study suggested a solution to balance the data by using oversampling and under-sampling techniques. The data, which had been improved with SMOTE (Synthetic Minority Oversampling Technique) and kNN (k-nearest neighbors) (k = 5), demonstrated a better effect than the other algorithms that were studied. The TPR (true positive rate) for the rural and suburban areas, which are types of regions with very different imbalance ratios, was calculated before balancing the data at 46.9 % and 46.4 %. As a result, the TPR values were 63.5 % and 54.4 %, respectively, following the data balancing.

The mathematical model of a multi-section articulated bus has been improved in the article, which allowed to determine the stability indicators of the two and three-section articulated buses for the Metrobus system. The critical speed for the three-section articulated bus was 28.06 m/s and for the two-section articulated bus - 30.89 m/s. Since the motion of multi-section articulated buses will be carried out on separate lanes with a speed of 25 - 28 m/s, one can assume that the stability of rectilinear traffic of both two and three-section buses is provided. In non-stationary modes of motion with two-section articulated buses, the lateral speed of the first bus decreases by almost 8.5 % compared to the three-section and the second trailer-bus increases by almost 9.5 % compared to the three-section. In this case, the motion stability of multi-section articulated buses can be considered satisfactory, as the lateral accelerations in the center of mass of all sections do not exceed 0.45 g.

Every year, many people lose their health and/or lives on Polish roads. One of the reasons for this is behavior of pedestrians at pedestrian crossings, which affects the road safety. The aim of the article was to conduct experimental research, the idea of which was to study the behavior of pedestrians at pedestrian crossings in the city of Pila, the results of which can be applied to Poland. During the research, the behavior of pedestrians and the impact on the probability of a road accident were analyzed. Undoubtedly, the prevailing epidemic, during which people are in many respects limited, had an impact on the results obtained, therefore the number of people at the analyzed crossings may have decreased. The conducted research confirmed the Police statistical data that the most dangerous crossings for pedestrians are those without traffic lights.

The results of an experimental study of efficiency of the cavitation treatment of a fuel mixture, based on A-95 gasoline and distilled water, for automobile internal combustion engines are presented. Cavitation treatment of this fuel mixture at a percentage of water/gasoline of 17/83 % allows increasing the cost of gasoline up to 15-20 % when operating engines on flat and sloping sections of roads and in traffic jams. Due to the cavitation treatment, the engine power is reduced by only 6/7 %. The design of the created automobile electromagnetic vibrating cavitator is described. Its application will not only save fuel, but increase the completeness of combustion of water-gasoline fuel mixture, i.e. improve the environment, as well %.