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The paper presents a proposed methodology for designing and planning research on driver behavior at pedestrian crossings using whole-vehicle simulators. It was assumed that dedicated research should be conducted in specific problem contexts. The problems identified were the identification of hazards and the risk of accidents involving vulnerable road users. The purpose of this identification is to determine the determinants of safety at pedestrian crossings, which should constitute guidance when designing new solutions for safety support systems at pedestrian crossings. A number of hazard factors were identified; divided into categories, including types of crossings, location, and surroundings; behavior of vulnerable road users; and attention (focus) distractors, both inside and outside the vehicle. A method for defining and selecting research scenarios and selecting a group of research participants was proposed. Additionally, it was proposed to conduct repeatable test scenarios for different driving speeds and different weather conditions. With respect to the publications on this topic, this work focuses on the process of designing and planning dedicated simulation studies, which may provide a source of guidance and good practices for other researchers. This is an example of how interdisciplinary research involving human factors, traffic organization, and ITS systems can be planned and implemented. [ABSTRACT FROM AUTHOR]

This study concerns the management of operational risk in truck transport using the reliability theory of risks. In this regard, the risk analysis of changes in the vehicle unavailability represents an important topic. In this study, the authors present their own method for analysing the phase changes in risk corresponding to successive sections (phases) of vehicle mileage. The presented risk analysis method is based on an integrated assessment of losses associated with the costs of incidental repairs and losses caused by lost income during vehicle downtime. This includes the following: assessment of differences in average risk and differences in the coefficient of variation in the time series of vehicle mileage phases, indicating the outliers and extremes of phase risk, identifying their physical causes and testing the statistical significance of phase risk differences. The proposed method is described mathematically and verified experimentally based on the operational data concerning trucks from two selected brands (20 trucks from each brand). We show that the method can be used to predict the continuity of transport services in the short term (one-year horizon). The method could also be useful to compare vehicles of different brands in the context of their sensitivity to operational risks. [ABSTRACT FROM AUTHOR]

The development of public transport systems presently focuses on sustainability. In this situation, the issue of user (passenger) migration has become important to the transport company as a service provider. This paper presents an integrated model of the operational risk of vehicle incapacity, including the following: costs of incidental repairs, costs of unplanned downtime and costs resulting from potential user migration. The paper presents the results of operational research on buses of two makes over a period of 6 years, in the mileage range of 0–420 000 km. The authors have determined the risk as a regression function of operational mileage to estimate the optimum life cycle. The quality of the vehicle was assessed using the criterion of the maximum cost of the operational incapacity risk being equal to the current residual value of the vehicle. The research results confirmed the suitability of the integrated risk model for a comparison of vehicle makes and assessment of their reasonably foreseeable life cycle in a balanced carrier-vehicle-user system. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the impact of the categories of bus downtime caused by the necessity of their repair on the availability indicator. A retrospective study covering 12 years of bus operation was carried using the selected municipal transport company as an example. The share of the selected categories of downtime in the total time of vehicle downtime was analyzed. The Spearman's rank correlation coefficient was used for the analysis. The research covered seven makes and types of buses and six categories of downtime. A ranking of the downtime categories was developed according to the criterion of the statistical dispersion of stoppage time as a measure of their unpredictability. It was shown that categorized unavailability was strongly dependent on the rank of downtime and loosely dependent on the age of buses. In practical applications, the test results may be useful in improving the fleet maintenance processes, selecting the make of new buses or development of models for safety margin availability. [ABSTRACT FROM AUTHOR]

A proposal was presented to assess the incapacity risk of commercial vehicles performing transport tasks under market conditions. The risk assessment model in the form of cost was used, which is based on the determination of operational efficiency, referring the probable costs of ensuring the reliability of the transport system to the estimated threshold income. It includes costs: incidental repairs, unplanned downtime and resulting from the presumed loss of client's trust. Operational research were carried out on a group of several dozen vehicles, registering their operational states during several years of use. The results of the research confirmed the suitability of the incapacity risk model for predicting potential expenses for guarantee the vehicle's continuity of running in the company and to verify the selection of the vehicle brand and the period of use. [ABSTRACT FROM AUTHOR]

The paper describes operational efficiency research of city buses from two manufacturers during the 6 years of operation under real conditions. The presented operational efficiency assessment model includes unplanned incidental repairs costs, downtime costs, as well as the likelihood of losing customer-passenger's trust. The results of the efficiency calculations were used to estimate the expected costs of buses' incapacity risk. It has been demonstrated that the operational efficiency and incapacity risk costs can be a criterion for the optimal period of operation, as well as the criterion of comparison of bus makes in a transport company. [ABSTRACT FROM AUTHOR]

When a trolleybus travels through insulated sections of the overhead contact line, it experiences momentary power interruptions, which adversely affect the vehicle's on-board auxiliary subassemblies. To reduce these negative effects, one can harness energy recovered via regenerative braking. A model power supply circuit diagram for structural systems of the trolleybus is proposed. Simulation tests were carried out to develop a method for analyzing power supply to trolleybus auxiliary devices and verify it in a real-life example. The results allow determination of the limit power that can be generated by the trolleybus drive system to feed auxiliary devices during interruptions in power supply from the overhead contact line. The possibility of powering the on-board auxiliary equipment of a trolleybus using energy from recuperation with a traction motor is presented. [ABSTRACT FROM AUTHOR]