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The use of robots with their partial damage is not common, and it is not used in safety terms. If the robot works in a controlled environment after partial damage, the robot can be used for a short period of time when the speed of moving and weight of the load are reduced. In the event of damage one of the arms of the parallel robot, the parallelism of the movable platform towards base is lost. This results in a loss of accuracy, which in the case of shortening one of the robots arms is reflected by a gradual change in the distance of the removal site from the storage site. This change is bigger with the greater distance of the center of gravity effector from the robot output flange. For the short-term unavailability of replacement arms, it was decided to continue the training with the robot with rebuilt and reinforced arm. This article concerned with performing a control measurement to detect the deviation value that could be compensated in the execution of the individual cycles of the robot. The measurement compared values of pose accuracy and pose repeatability of the robot after damage by using measured compensated deviations.

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.

The article proposes a technological line for recycling the blast-furnace slag. This line makes it possible to obtain the crushed stone for road building, which has high water and frost resistance. The design of replaceable working equipment of a single-bucket excavator, with replaceable working tools for loosening frozen slag in dumps and preparing it for use in road building, is proposed. The results of testing the manufactured replacement working equipment are presented. The results of mathematical processing of experimental data using the approximation method are presented, as well.

The purpose of the study was to identify problematic issues in the operation of bucket elevators during the loading and unloading of grain, which can lead to damage to seeds. To achieve this goal, methods of analysis and evaluation of factors that affect the damage rate of grain were used. The main results were an increase in the safety of the grain loading and unloading process using bucket elevators and a reduction in the risks of crop losses. The analysis of grain damage by a bucket elevator is of practical importance for the agricultural sector and can bring the following practical benefits: reducing the risk of product losses, as it helps to identify problem areas in the operation of the elevator and develop measures to eliminate them, improving the efficiency of work and the quality of seed grain.

Results of the study of the roughness and friction properties of the road surface of urban streets influence on the traffic safety are presented in this article. As a result of this study, an empirical dependence was obtained, reflecting the relationship between the traffic speed and a load factor under different traffic conditions; the relationship between the flow density and street capacity was also determined. The maximum permissible value of the friction coefficient for experimental streets is 0.4, and 50 % of the object of study meets the requirements of operation; 50 % does not. From the proposed graph of the relative dependence of pavement roughness and safety factor, it follows that the most dangerous are the streets, the pavement roughness of which is in unsatisfactory condition. To effectively solve the problem of destruction of the road surfaces, it is first of all necessary to eliminate the cause of the damage that occurs, not just its consequences.

Autonomous control and the associated development of relevant intelligent control systems have become an issue of interest in the automotive sector decades ago. This article deals with the issue of subsystem validation planning. The theoretical part describes the issue, characterizes the current state of the researched issues in selected scientific publications and characterizes the data and methods with which the authors work. The practical part of the article analyzes a case study in the form of a model project, its structure, testing requirements and design of a test campaign plan. The output is a calculation and decision tree, which determines the optimal variant of the number of vehicles so that the validation is completed, while minimizing time and financial resources.

Delivery time means a certain period in which the carrier is obliged to transport the consignment from one place to another. The delay occurs when the carrier does not deliver the consignment to the consignee within this period. The authors analyse individual legislative documents regulating the transport - legal conditions of international transport. In addition, they present the reasons for the delay in delivery of the consignment and point to the carrier's liability for non-fulfilment of the obligation to transport the consignment within the delivery period. By comparing the results, authors state that there is a diversity of regulations in the field of international transport, especially in the context of the multimodality development. Such a diversity in regulations causes inconsistencies in the transport market and therefore there is a need to harmonize unimodal transport systems.

The main objective of the study was to develop a model and analyze the thermomechanical behavior of the hub material of the vehicle brake disk. The simulation strategy was based on the solution of the three-dimensional problem of the theory of elasticity for the case of effect of external loads and temperature fields on the metal structure element of the vehicle brakes. To solve this type of task of the theory of elasticity, the differential equations of the second order were used for the first time. Adaptation of the proposed model, completed in the article, has proved the correctness of use of these equations in modeling the thermomechanical processes with determination of stresses and displacements in unevenly heated rotary cylinders of the final length. The proposed method can be applied with high efficiency in stress strain state simulation of individual parts of vehicles.

This study proposes an approach to determine transport delays at unsignalized intersections, according to the theory of stationary Poisson flow and considering the priority of vehicle traffic in competing directions. The accuracy of the proposed approach was estimated by comparing the average values of delays of vehicles performing a left turn from a minor road and their actual values obtained as a result of processing data from field studies. The results of the accuracy evaluation at unsignalized intersections of non-equivalent roads indicate the obtained results' reliability, because the calculation error does not exceed 10 %, as well as the possibility of using the developed approach in the process of transport planning and unsignalized intersections modelling.

Traffic safety assessment is an essential part of traffic planning and engineering. At uncontrolled intersections, the severity of crashes has increased manifolds. This is due to the fact of not following the priority rule during the right-turning movements. In conventional methods, past accident records were used to analyze traffic safety. However, the drawbacks of the traditional method to estimate the severity require a lot of accident data for analysis to draw any conclusion and suggest safety measures. The accuracy of the record of accidents and details is highly uncertain. Therefore, surrogate safety measures are being used to analyze the safety. In the present paper, the gap acceptance time (GT) is used to examine the risk and the speed and gap values define the level of risk and severity (LORS). Moreover, using the value of the critical gap, the probability of risk is estimated. Further, the level of risk and severity is computed based on the gap and speed data of vehicles at an uncontrolled intersection. Hence, with the speed and gap data, the level of risk and severity is classified as low risk, high risk and low severe, and high severe. The methodology implemented is validated by using the actual accident data.

Water is a necessary component of urban structures and a source of life. Nowadays water distribution system's performance might decline for various reasons, resulting in water waste, hence, to maintain a reliable water distribution network, assessing each water distribution study's validity is crucial. Therefore, this research has focused on using durability assessment to evaluate a water supply system. A water distribution network includes an overhead tank and nodes, pipelines, and nodes. The hydraulic properties of every node as well as pipe, including pressure and flow, are calculated utilizing EPANET. This research evaluates the reliability analysis based on the benchmark data's various diameter of pipes, such as 0.6 m, 0.4 m, 0.3 m, 0.2 m, and 0.15 m, usage. Finally, this research analyses the reliability of each set of diameter pipes in the water supply system.

Cylinder liners of an automotive internal combustion engine are subject to significant losses during operation. Severe operating conditions of cylinder liners lead to the appearance of various defects that must be eliminated to ensure the performance of the internal combustion engine. Currently, several methods have been developed for restoring and strengthening the inner surface of cylinder liners of automobile and tractor engines. Analyzing the considered methods for strengthening and restoring cylinder liners, their advantages and disadvantages from the point of view of increasing their durability, it can be assumed that the high-quality restoration of cylinder liners will be provided by a method of applying a coating by centrifugal induction sintering of powder material. Self-fluxing powders were used as baked powder material.

Earthquake and tsunami preparedness is important to plan, especially in the earthquake and tsunami-prone areas, such as Banda Aceh. This study evaluates the tsunami evacuation routes' performance using the width of the road, travel time and the Degree of Saturation (DS) parameter. Some of the Degree of Saturation (DS) of the road segment surprisingly reach 1.0 to 3.18, exceeding the recommended 0.75 standard DS ratio. That indicates that the existing roads cannot accommodate traffic flow during evacuation. This study recommends the evacuation process by walking. Thus, developing the pedestrian routes according to evacuation safety requirements is strongly encouraged. Further, more escape buildings reachable within 15 minutes of evacuation time should be planned in the area. The pedestrian routes need to be designed separately from that of the traffic flow.

Unfortunately, nowadays, choosing the right child seat is a real problem, especially for new parents. When choosing a child seat, parents have to consider many factors. These include the method of mounting the seat, the mass of the seat, compatibility with a pram and information about crash tests and approvals. The main purpose of the article is to draw attention to the problem of choosing a safe child seat and the purchasing preferences of parents or legal guardians who decide to buy a child seat. For this purpose, a survey was conducted on a group of 950 people with children. The conducted research has shown that the main parameter influencing the choice of a child seat is the price for men and the social opinion and mass of the child seat for women. In addition, research has shown that most people decide to buy a child seat based on the installation system using a standard ISOFIX base.

The authors of this manuscript present development of a prototype protective UV-C half-face mask. The first stage of this study focuses on proposing a UV-C half-face mask design and the second phase investigates the quality of printings, 3D/2D roughness and porousness of three different printed samples of PA12. Development of the protective half-face mask used the non-destructive technology of 3D scanning of the human body by the Ein Scan scanner. As a part of the experiment, three samples were prepared with Sinterit Lisa, EOS Formiga and HP jet fusion printers. SLS and MJF technology were used during the experiment. The experimental observation of the structure of the surface was secured using the Alicona Infinite focus G5 device. The conclusions present the study's results and the authors' recommendations for other developers dealing with the development of the protective face masks.

The rail rolling stock undercarriage condition monitoring is proposed by using an automated measuring system, located on the railway track and measuring the specified parameters of the wheels directly, while the train is moving. Regular undercarriage condition monitoring reduces the costs of preventive maintenance of rolling stock without compromising the traffic safety. An algorithm has been developed for the operation of a special software package for visualizing and assessing monitoring data on the condition of the undercarriage of rail rolling stock. The software package consists of separate software modules that can be used independently of each other. It is possible to make short- or long-term predictions of the behavior of any of the monitored parameters using an proposed automated measuring system.

A surprising number of people die on Polish highways every year. Despite the fact that number is decreasing year after year, it is still rather considerable. Due to the epidemic, the costs of the road accidents were significantly lowered, but they still remain fairly large. Understanding the roads where the majority of accidents happen and the anticipated number of accidents in the next years are necessary to lower this number. The purpose of the article was to forecast the number of accidents that would happen on Polish roads based on the kind of roads. To do this, annual accident statistics from the Police's statistics for the years 2001-2021 were reviewed, and a forecast for the years 2022-2031 was produced. It is clear that either the accident rate is increasing or it is steady. Predictions also suggest that a large increase in accidents on Polish roads may be expected given the current situation.

The impact of polyphosphoric acid (PPA) polymers and crumb rubber (CR) on bitumen's properties to enhance its performance was examined in this study. Laboratory samples were created with varying percentages of PPA (0.5 % to 2 %) and CR (6 % to 18 %) and subjected to extensive testing. Findings indicated that the combination of PPA and CR led to notable improvements in bitumen performance, including increased viscosity, softening point, elasticity, and recovery rates at elevated temperatures. Specifically, samples with 18 % CR and 1.0 % or 2.0 % PPA demonstrated exceptional rheological properties and strength. The optimal combination (18% CR and 1.0% PPA) resulted in a uniform structure, while the maximum CR content did not compromise bitumen integrity. Both additives effectively minimized temperature sensitivity and aging, enhancing the bitumen's performance class significantly.

To remain competitive in a transport market, railway needs to increase reliability and to reduce the transport costs. Timely detection of a fault or defect can prevent a possible accident and can reduce maintenance costs. This paper presents a model for selection of locations for wayside train monitoring systems that are used to detect faults on the wagons. We present two models: first, based on multi-criteria decision making method is used for selecting a macro location, and second model based on fuzzy logic is used to determine a micro location of a wayside train monitoring system work station on Serbian rail network.

Accident prediction models are mathematical expressions or algorithms used to determine the causal factors for road accidents and road safety engineers are using these models, as well. Modelling this kind of accident is quite challenging and required good quality of data. The results of the artificial neural network model, Gaussian processes model, and support vector machine model are compared for vulnerable road accident frequency in this study. The accident frequency dataset comprises 218 records, with 146 designated for training purposes and 72 reserved for testing. The model's accuracy was contingent on: the mean absolute error, root mean square error and coefficient of correlation. The findings suggest that for predicting the vulnerable road user accidents on roads, the artificial neural network gives better correlation results as (0.912) that the support vector machine (0.879) and Gaussian processes (0.853).

The lifespan prediction of the bus body of the load-bearing structure has been made and compared to the results of real operation. The maximum approximation of the simulation modelling results in Matlab Simulink to real operation is explained by taking into account a sufficient number of factors influencing durability. This research has the particularity that it allows determining the durability of the bus body even at the design stage, which was not possible with accelerated tests or during the operation of the bus on real routes. The obtained results can be used by bus manufacturers at the design stage, allowing them to change the construction and technology of anticorrosion protection, thereby influencing the durability. In addition, operating organizations will be interested in the obtained results when using the developed methodology in various operating conditions.

The paper deals with the issue of GNSS interference and its subsequent impact on airport approach procedures. It discusses the problem of GNSS signal interference and interference identification on a practical example of a small regional airport in Zilina, located close to the highway, through research aimed at its identification, a proposal for the location of a monitoring station and subsequent practical verification. The paper seeks to analyse and provide recommendations for enhancing safety and reliability in GNSS approaches. Given the need to develop the air transport, it is important to ensure the safety and continuity of service provision at small regional airports. The GNSS approach at airports with insufficiently equipped navigation infrastructure seems to be one of the most suitable. Introduction of the GNSS interference monitoring in the final instrument approach phase would increase the safety and reliability of the flight.

This paper displays the design and application of a model that simulates the queuing system of a fictional post office. Starting point for solving more complicated optimization tasks is to create a system model that consists of elements of reality and the relationships between these elements. The key part of the paper includes the model of a queuing system of a post office created in Anylogic simulation software. The model of the post office displays post office with 5 postal counters, a certain input flow and a certain service time with an exponential probability distribution. The model also includes statistics and cost calculation.

Development of public transportation is meant to bridge the divide between cities and encourage development results. The inter-city transportation opens up opportunities for the inter-city trade, reduces costs and increases labor mobility, thereby promoting the inter-city development opportunities. This study uses the factor and cluster analyses. Analysis of factors is performed to determine the most dominant factors. The cluster analysis is used to identify the advantages and disdvantages of five modes of transport, namely taxi, trade rail, economy bus, mini bus, and executive bus. This study aims to determine the perception of users of Medan-Pematang Siantar route service. The results of this study show that there are five dominant factors that are considered before the service users decide on the mode of transport to use, namely the comfort factor, which is the most important consideration, followed by the time factor, cost factor, accessibility factor and safety factor.

Fierce rivalry in the transport market raises serious reassessment and implementation of new approaches to logistics companies and trade enterprises in marketing of goods. To maintain the volume of domestic sales and output to the external one, producers and trading firms are forced to expand their trade and economic relations that occur in other regions. The integration of the world economy and policy orientation of foreign trade to free trade greatly simplify the task of setting up the free trade and economic connections, but the question is how quickly and efficiently, with the least costs, it is necessary to put the goods in the right region to the customer.In modern market conditions, international container transportation of goods between Ukraine and the European Union countries has a prospect of development, as each year the number of orders in transport and logistics enterprises increases. After analyzing the status of orders, the problem has been detected and widely connected with the method of organization of container cargo delivery in international communication and the formation of rational technology of serviced. To solve this problem a method of logistic approach to the system of containers transportation has been proposed based on the cybernetic model "white box". The initial stage of its implementation involves formation of the limitation system of input parameters and factors that are consistent with the needs of the customer firm and the company performing transportation. Ten alternative order services schemes, each of which takes into account the possible combinations of operations, has been proposed.Based on the company "Inter Trans Logistic", which serviced the order of the company "Agricultural Holding August" for the transportation of rape seeds, 10 tons of corn on demand and a portion of sunflower oil 20,000 liters, according to their applications for transportation, a logistic approach using a cybernetic model "white box" has been implemented. Based on the mathematical models of changes in the total costs of the international container cargo shipping company of the customer, it has been shown that the maximum expenses are occurring in the implementation of the scheme 1 service order. In that case, the costs have been in the range of 848.72 to 7455.41 US $, according to a certain series of experiments. Based on the condition of the minimum cost function for container transportation, scheme 1 has been chosen as limiting scheme of service order against which the assessment carried out changes of the total costs in the implementation of other schemes. In percentage display according to Scheme 1, the following percentage intervals have been deducted for the reduction of sales costs: Scheme 2 - 12.70 to 34.98%; Scheme 3 - 2.93 to 12.00%; Scheme 4 - 2.06 to 10.88%; Scheme 5 - 1.69 to 4.25%; Scheme 6 - 0.87 to 3.28%; scheme7 - 0.97 to 2.58%; Scheme 8 - 1.64 to 4.45%; Scheme 9 - 2.66 to 11.77%; scheme 10 - 2.33 to 9.94%.The results of experimental studies indicate that when the proposed methodology of the logistic approach, using the "white box" based on the company "Inter Trans Logistic" to international container transportation of goods in relation to the application of the company "Agricultural Holding August" for transportation, the scheme 2 sequence o

The paper deals with the relationship of increasing road safety through the support of bus service. The objective of the paper is to analyse the factors affecting road safety. Subsequently, the impact of the bus service support on road safety is expressed through those factors. The paper highlights the multiplier effect of the bus service support on road safety increase. First part of the paper analyses factors affecting road safety. The factors are divided into three groups in terms of infrastructure, vehicles and drivers. Further part emphasizes the possibilities for improving individual factors under the support of bus service. The last part of the paper processes a theoretical model which reflects the impact of the bus service support on increasing road safety.

Premature failure or damage of parts and components of the oil and gas well piping, as well as pipelines for transport of oil and gas, are generally caused by the simultaneous influence of a large number of technological, metallurgical, structural and exploitation factors. Therefore, the convenient structural solutions, which provide the mechanical safety of parts and integrity of structures, can be realized only through total comprehension of their behavior in various operation regimes. Importance of technical diagnostics for monitoring and state analysis of welded pipes/pipelines in oil industry is considered in this paper. An analysis of causes of the welded pipes failures in exploitation has been performed through use of the fault tree analysis. Based on the suggested structure of a database, regarding the causes of failure, possibilities are presented to set measures for prevention of damage and failure of welded pipes/pipelines and for extension of their service life. A suggestion for improvement of the organizational scheme for monitoring the state and maintenance of welded pipes/pipelines during the exploitation has been made, as well.

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.

The wear of cutting elements of auto graders allowed in practice causes an increase in the cutting force by 3 to 4 times, the energy intensity of the cutting process by 1.4 to 3 times, the cost of soil development by 8 to 15 % with a decrease in productivity by 10 to 30 %. This increases the stress state of the entire machine and reduces its operational reliability. Excessive wear of cutting elements leads to economic inexpediency or practical impossibility of further operation of machines.

A survey of cyclists in the city of Qazvin, Iran, was conducted by focusing on improving the bike lane attributes (increasing width, increasing attractiveness or appeal of the bike lane (painting, planting …), improving pavement conditions, improving sight distance and removing obstacles in the bike lane). It was seen that there was no difference between age groups. Two important priorities for the men group were increasing the lane width and improving the sight distance, while the women considered improving the pavement conditions and the appeal of the bike lanes. Increasing the lane width and improving the pavement conditions for the recreational group and increasing the lane width and improving the sight distance for the non-recreational group were the most important improvements. It can be said that increasing the width of the bike lane was the most important factor for almost all groups.