Abstract Analyzing route choice behavior and understanding the heterogeneous impacts on passenger decisions are key to improving transportation service quality in integrated suburban railway and metro networks. While existing studies focus on metro systems using Mixed Logit (MXL) models or clustering methods with Multinomial Logit models, these approaches struggle to capture the diverse factors in travel scenarios and the complex nonlinear relationships in decision-making. This study integrates Latent Dirichlet Allocation with Machine-Learning models like eXtreme Gradient Boosting (XGBoost), Support Vector Machine, and Random Forest to analyze passenger behavior within Shanghai’s composite rail network. It identifies key influencing factors such as socio-economic demographic characteristics, travel purposes, and the express-to-local departure ratio. XGBoost outperforms other models, including the traditional MXL, in predictive performance. The study highlights significant heterogeneity in route choices across different passenger groups, underscoring the need for personalized transportation solutions. Based on these findings, this study proposes the following actionable suggestions for suburban railway in the composite network: In terms of operational optimization, it is proposed to add express train overtaking stations in key commuting corridors and optimize the timetable to reduce transfer waiting times, thereby improving overall travel efficiency. Besides, time-of-day differentiated pricing and combined-ticket discounts are proposed to improve the rationality of the ticket-price structure. Finally, it is recommended to enhance the personalized route recommendation system.
Transportation engineering, Transportation and communications
Arun Kumar, Sumit Chakravarthy, Rashid Amin
et al.
ABSTRACT This paper investigates the integration of rate‐splitting multiple access (RSMA) into cellular vehicle‐to‐everything (C‐V2X) networks to enhance resource allocation and interference management in decentralized, ad‐hoc vehicular communication environments. C‐V2X facilitates communication among vehicles, infrastructure, and pedestrians, and traditionally relies on orthogonal frequency division multiple access (OFDMA). However, OFDMA's rigidity limits its effectiveness under dynamic interference and imperfect channel state information (CSI) conditions typical of vehicular networks. RSMA, which blends features of spatial division multiple access (SDMA) and non‐orthogonal multiple access (NOMA), provides a more adaptive framework by splitting messages into common and private parts, thereby improving spectral efficiency and interference handling. To assess RSMA's applicability, the LTEV2Vsim simulator was extended to include RSMA functionality, incorporating features such as reputation‐based grouping, group‐wise resource synchronization, and simplified beamforming. A dynamic grouping algorithm selects high‐reputation vehicles as transmission leaders to form multi‐vehicle groups of varying sizes for RSMA‐based transmission. For interference modeling, self‐interference is excluded from SINR calculations, and beamforming‐based inter‐vehicle interference is approximated. Simulation results reveal that RSMA outperforms OFDMA in terms of spectral efficiency and adaptability, particularly under conditions of incomplete CSI and varying interference. The findings confirm RSMA's suitability for complex and fast‐changing vehicular environments, indicating its potential as a robust multiple access scheme for future C‐V2X deployments.
In the centralized scheduling mode of automated container terminals, Automated Guided Vehicles (AGVs) often experience decision-making delays caused by system information-processing bottlenecks, which significantly affect path-planning efficiency and are particularly evident in sudden-traffic scenarios. To address this issue, this paper incorporates the artificial potential field (APF) into the cost function of Model Predictive Control (MPC) and develops a dual-trigger mechanism for lane-change and lane-return MPC obstacle-avoidance framework (Event-Triggered Model Predictive Control, EMPC). This framework integrates an obstacle-triggered local optimization mechanism and a lane-change trigger, enabling AGV to perform autonomous and dynamically responsive local obstacle avoidance, thereby improving local path-planning efficiency. Furthermore, a Proximal Policy Optimization (PPO)-based strategy is introduced to adaptively adjust the obstacle-weighting parameters within the EMPC cost function, enhancing both obstacle-avoidance and lane-keeping performance. Under multi-lane overtaking conditions, a lane-change trigger—implemented as a dual-phase “lane-change–return” mechanism—is employed, in which lateral optimization is activated only during critical phases, reducing online computational load by at least 28% compared with conventional MPC strategies. The experimental results demonstrate that the proposed PPO–EMPC architecture exhibits high robustness, real-time performance, and scalability under dynamic and partially observable environments, providing a practical and generalizable decision-making paradigm for cooperative AGV operations in automated container terminals.
[Objective] Analysis is carried out targeting the power outage issues occurring during the operation of urban rail transit substations, the key components causing power failure are identified, and the safety hazards leading to substation power outages caused by these critical components are addressed. [Method] By analyzing the causes of power outage in substations, it is pointed out that the voltage relays are the key components leading to substation power failure. The internal circuit working principle of the low voltage detection relay in a 400 V distribution box is examined, and parameters of the internal circuit problematic parts are calculated. The reasons for abnormal operation of key components are argued based on the calculation results. Based on the cause analysis, an internal circuit optimization scheme is proposed. The optimized internal circuit is then analyzed and tested to verify the reliability of the voltage relay. [Result & Conclusion] After optimizing the voltage relay internal circuit, maloperation caused by secondary detection circuit failures inside the substation 400 V switchgear cabinet is effectively avoided. The detection and logic judgment circuits of the voltage relay should be designed with electrical isolation, aiming to enhance reliability of the detection circuit in various operating scenarios, ensuring the adaptability of detection components to different working conditions.
Research relevance. Modes accompanied by increased sliding of a wheel with negative viscous friction, characterized by reduction of friction force at growth of sliding speed, can arise at the movement of the vehicle. In these cases, a loss of stability may occur, resulting in the excitation of auto-oscillation phenomena in the electromechanical system (road-wheel-mechanical drive-electric motor). The emergence of this process sharply increases the dynamic load of the system, which can lead to its failure or breakdown. As a consequence, the development of suppression methods of auto-oscillation phenomena is considered to be an urgent task.Purpose of the research. Verification of operability and efficiency of the suppression method of auto oscillations in the electromechanical system of wheel drive during braking of the vehicle.Materials and Methods. With the help of Lyapunov’ function analysis for the electromechanical system of wheel drive the suppression method of auto oscillation phenomena is substantiated. The study of the algorithm performance has been carried out with the use of MATLAB Simulink program complex.Research results. The operability and efficiency of the algorithm is proved by methods of simulation mathematical modeling, which allows its further use in the development of traffic control systems. In case of braking of the vehicle equipped with antilock braking system with the function of suppression of auto oscillations on a slippery support base the reduction of amplitudes oscillation of angular velocities of wheels by 80% and braking moments by 96% is observed. When this vehicle is braked on a high adhesion base, the amplitudes are reduced by 98% in angular velocities and 81% in torques. In simulation modeling of vehicle braking dynamics on a support base with low adhesion properties it has also been shown that in these cases the evasive maneuver can be performed, which indicates on the increase in controllability and active safety of the vehicle.Conclusion. The practical value of the study lies in the possibility of using the developed algorithm for suppressing auto oscillations in practical application as part of vehicle control systems. The developed algorithm can be used on vehicles of different classes equipped with individual traction electric drive of driving wheels.
Water-lubricated oil–water flow is an effective low-energy consumption method for pipeline transportation. This study proposes a novel wellbore lubrication fitting (WLF) for developing a core-swirling flow to reduce flow resistance and enhance lubrication efficiency. The pressure drop across the lubricating fitting, the maximum oil volume fraction at the overflow outlet and the drag reduction percentage of core-swirling flow were taken as the indicators, and the fluid calculation software Ansys Fluent was applied to optimize the structural parameters of the WLF with orthogonal and single-factor methods. The experimental study was carried out with mineral oil and tap water. The results indicate that the swirl generator can develop a stable and low-viscosity liquid annulus to isolate the oil from the pipe wall and reduce the flow resistance of viscous oil. The optimized WLF demonstrates the clear core-swirling flow with input velocity between 0.48 and 0.62 m/s. The experimental pressure drops deviate from the simulated data within ±25%. The drag reduction percentage of the core-swirling flow is above 90% with the input velocity above 0.51 m/s. The results of this study have important engineering value for efficient application of WLFs.
Jarosław KOZUBA, Marek MARCISZ, Sebastian RZYDZIK
et al.
The objective of the undertaken research was to characterize and evaluate the impact of weather and lighting conditions on recording terrain anomalies in the photographs obtained during a UAV photogrammetric flight. The present work describes the use and capabilities of the UAV in the mapping of photo acquisition conditions similar to those performed during inspection flights with the use of a manned helicopter equipped with a hyperspectral camera, in the target range of visible light. The research was conducted in the southern part of Poland (between Gliwice and Katowice), where 7 routes were selected, differing from one another in terms of terrain anomalies (buildings, types of land areas, vehicles, vegetation). In the studies, which involved photogrammetric flights performed using a UAV, different seasons and times of day as well as changes in light intensity were taken into account. The flight specification was based on the main parameters with the following assumptions: taking only perpendicular (nadir) RGB photographs, flight altitude 120 m AGL, strip width 160 m, GSD ≤0.04 m and overlap ≥83%. The analysis of the photographic material obtained made it possible to correct the catalog of anomalies defined previously, since the recognition of some objects is very difficult, being usually below the orthophotomap resolution. When making and evaluating orthophotomaps, problems with mapping the shape of objects near the edges of the frame were found. When a 12 mm lens is used, these distortions are significant. It was decided that for the purpose of generating training data from orthophotomaps, only the fragments containing objects which shape would be mapped in accordance with the real one would be used. Thus, the effective width of orthophotomaps obtained from simulated flights will be approximately 100 m.
Celestino Sánchez Martín, David Calonge Cases, Miloš Milenković
Despite the increasing relevance of Open Science (OS) in the European research landscape, very few publications have addressed the analysis of its role within the European rail context. To this effect, the present paper aims at contributing to shed light on the topic by setting the cornerstone for a differentiated analysis of OS in this sector. In order to do so, the analysis is divided into 2 main sections. The 1st provides an overview of initiatives and experiences regarding OS, which have been recently carried out in the sector. The analysis of initiatives and scientific publications has shown that Open Data (OD) is the area attracting more attention and with more potential for expansion mainly due to the commercial interest of the data. As expected, the use of Open Tools (OT) is common but, interestingly, a growing interest in the development of OT in the sector has been detected. The creation of Open Standards (OSt), developed by specific rail stakeholders’ groups or by coalitions of different stakeholders is increasing in the last years. Amongst the OS areas analysed, Open Access (OA) and Citizen Science (CS) have shown less progress. However, tendencies toward an increasing interest in these areas within the sector has been also detected. The 2nd section aims to uncover the issues or barriers preventing a wider spread of OS specifically in the rail sector and suggest regulatory avenues and actions to overcome them. The identified issues revolve around 3 topics: the lack of initiative on behalf of the European Union (EU) to a) engage other stakeholders beyond the field of research, and b) leverage untapped OS potential in sector-specific situations, which could contribute to its development; and finally, the absence of a sector-specific OS framework. The establishment of such a framework could have a significant positive impact in OD, which is the most appealing area and thus contributing to the uptake of OS as a whole in the sector. In view of such issues, the present paper suggests the establishment of: (1) a European Rail Open Science Policy Platform in order to create a forum-like space in which to align the stakeholder’s positions, and (2) a Joint Rail Data Action Plan to design an OS governance framework, with the aim to ensure the usability, quality, and reliability of data. After identifying the state of OS in the rail sector and the uncovering of several issues that are hindering its development, this paper concludes that the constant further monitoring with regards to needs, challenges and interests (or lack of such) of the different rail stakeholders is key to ensure the continuous development of OS.
The paper considers a special class of routing problems with the objective of minimizing the passengers risk. A major area of application of the low risk models is helicopter transportation widely used in the petroleum industry. In general, the total risk is considered to be proportional to the number of passengers exposed to landings and takeoffs during several multi-leg flights. We give a review of most of the studied models and demonstrate their links with the known problems of combinatorial optimization, such as the minimum latency problem, the multiple deliverymen problem, single machine and parallel machine scheduling, etc. In this paper, we focus on the problem of minimizing total risk, provided that the pickup from a number of locations is performed by two flights, and it is allowed that a location is visited by both flights, splitting the pickup demand. We show that the problem in NP-hard and admits a pseudopolynomial-time dynamic programming algorithm. We also develop a fully polynomial-time approximation scheme and a fast 5/4-approximation algorithm. The results of computational experiments with our algorithms are reported.
To ensure the computational accuracy for the offshore high voltage direct current substation local structure and its large and complex electrical equipment, it is necessary to reduce the modeling complexity and improve the calculation efficiency. Thus, a simplified vibration model with constant key physical parameters was established; the converter valve was used as a test design example and a lower number of samples was used. Finally, the response surface fitting was carried out. Based on the machine learning concept, problems such as the loss of physical meaning of complex system matrices and low iteration efficiency, caused by high-dimensional matrix operations were avoided. In addition, the deterministic screening experiment design greatly reduced the number of samples needed while also ensuring the second-order effect. The fit between the response surface equation and experimental results was good after optimizing the relevant design factors based on the vibration equation. The comparison between the simplified vibration converter valve model and the original complex model has shown that the errors for various physical parameters and the vibration characteristics were below 5% and that the model simplification degree was 95%.
The millimeter wave detector has been widely applied in short-range detection systems. However, it can be easily disturbed by the ultra-wideband electromagnetic pulse (UWB EMP). In this paper, we proposed a simplified model to investigate the coupling laws of UWB EMP to the millimeter wave detector. With the help of finite integration technology (FIT), the coupling process can be visualized, and the most sensitive pose and the coupling path are analyzed. The irradiation tests are carried out to verify the simulation results. The results show that the shielding effectiveness (SE) of the detector in the vertical state is the worst, and the UWB EMP enters the detector mainly through the circular opening. Under the irradiation of UWB EMP, the detector shows three phenomena: interruptions, constant false alarms, and damage. The interruptions can be recovered by power reset, while the constant false alarms and damage are irreversible effects. The results can be employed to reinforce the electromagnetic compatibility (EMC) of the millimeter wave detector. With the increasing use of short-range detection systems, the EMC of existing products must be improved.
Oleg Bazaluk, Alim Ennan, Serhii Cheberiachko
et al.
In this paper, a solution to the problem of the change in the pressure drop in a respirator filter during cyclic air motion is suggested since the current theory of filtering is based on steady-flow processes. The theoretical dependence of the pressure drop in the respirator filter on air flow rate is determined, which is represented by the harmonic law, which characterizes the human respiration process during physical work. For the calculation, a filter model was used, which is represented by a system of parallel isolated cylinders with a length equal to the total length of the filter fibres surrounded by porous shells formed by a viscous air flow field, with a size determined by the equal velocities of the radial component of air flow and undisturbed flows. The flow-around process in the proposed model of air flow through the respirator filter is described by the Brinkman equation, which served to establish the total air flow resistance in the proposed system under conditions of velocity proportionality. It consists of two parts: the first characterizes the frictional resistance of the air flow against the surface of the cylinder, which imitates the filter fibre; the second—the inertial part—characterizes the frequency of pulsations of respiratory movements during physical performance. The divergence of the analytical results and experimental studies is no more than 20%, which allows the use of the established dependence to estimate the change in pressure drop in a respirator filter made of filter material “Elephlen” when the user carries out different physical activities. This allows the period of effective protective action of respirators with different cycles of respiration during physical activities to be specified, which is a very serious problem that is not currently regulated in health and safety regulations, and it also allows the prediction of the protective action of filters and respiratory protection in general.