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This paper presents a sensitivity analysis to assess the impact of random rail unevenness profiles on the generation of ground-borne vibrations. The random profiles are generated from a power spectral density function, assuming that the uneven rail surface is governed by a stationary Gaussian random process in space. Different proposals are employed to generate these profiles. A previously validated PiP model is used to perform a set of parametric studies, involving the dynamic simulation of a train–track–tunnel–ground system. It was found that the number of harmonics in generating ground-borne vibrations has a residual impact on the evaluated vibration levels. The main differences observed, although not significant, are attributed to the stochastic nature of the rail unevenness profile. More critically, it is important to highlight that different existing approaches for generating the PSD function have a pronounced impact on the evaluated vibration levels. [ABSTRACT FROM AUTHOR]

Railway-road crossings over rail tracks are intersections of two separate transportation systems that, from a safety standpoint, represent a high-risk point for all traffic participants. In the absence of adequate levels of protection at railway-road crossings, the danger significantly increases, as evidenced by the number of traffic accidents occurring at these locations. The subject of research in this paper is the impact of the human factor on safety at railway-road crossings in the Western Region, which encompasses the areas of Karlovac County, Lika-Senj County, Primorje-Gorski Kotar County, and Istria County. The aim of this study is to determine the safety conditions at railway-road crossings in the Western Region and compare them with the rest of the Republic of Croatia. Subsequently, the goal is to ascertain the extent of the human factor's influence on their occurrence. The working hypothesis states that accidents resulting in fatalities occur at railway-road crossings with low railway and road traffic on county, local, and unclassified roads in or near settlements because drivers fail to comply with regulations. To support the hypothesis, the study utilized scientific methods such as analysis and synthesis, descriptive method, induction and deduction method, and comparative method. The research results are based on secondary sources of data for the period from 2014 to 2023. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the relationship between the number of extraordinary events and the total number of accidents and serious accidents in railway traffic. The purpose of the paper is to estimate the total number of accidents and serious accidents on the track network of Croatian Railway Infrastructure (HŽI) until 2027. The results of the research are based on secondary data that are the subject of processing using statistical methods of correlation and regression analysis. The main finding of this paper points to the existence of a strong and positive relationship between the number of extraordinary events and the total number of accidents and serious accidents in railway traffic. The estimated number of extraordinary events and total number of accidents and serious accidents until 2027 indicates a trend of their further reduction. [ABSTRACT FROM AUTHOR]

Copyright of Engineer Military Bulletin / Muszaki Katonai Közlöny is the property of National University of Public Service and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The intrusion of foreign objects in tracks, one of the sources of injuries and fatalities in metro stations, can be solved as an anomaly detection task. However, the existing anomaly detection methods rarely consider the importance of updating the new knowledge from false alarm data, resulting in repeated mistakes. These methods are also impractical for edge devices that cannot afford the high calculation cost. A sequential updatable anomaly detection (SUAD) framework is proposed to tackle these problems. This framework is based on the Robbin-Monro algorithm and a fast version of Mahalanobis distance. A well-trained model of SUAD can continue to learn new knowledge through the sequential knowledge update module based on the Robbin-Monro algorithm without reviewing the old data. SUAD utilizes a new Mahalanobis distance calculation method based on principal component analysis. This new method exhibits a fast inference speed with a lighter model size than before. SUAD is evaluated on a self-built Metro Anomaly Detection (MAD) dataset and three public datasets. SUAD achieves an average area under the receiver operating characteristic curve score of 99.4% at image level and 99.6% at pixel level on MAD. SUAD also reduces at least 78% model size and 60% memory usage. Competitive results are also achieved in public datasets, including MVTec AD, beanTech Anomaly Detection, and CIFAR-10. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Civil Engineering (Polish Academy of Sciences) is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel numerical methodology is presented to solve the dynamic response of railway bridges under the passage of running trains, considering soil–structure interaction. It is advantageous compared to alternative approaches because it permits, (i) consideration of complex geometries for the bridge and foundations, (ii) simulation of stratified soils, and, (iii) solving the train-bridge dynamic problem at minimal computational cost. The approach uses sub-structuring to split the problem into two coupled interaction problems: the soil–foundation, and the soil–foundation–bridge systems. In the former, the foundation and surrounding soil are discretized with Finite Elements (FE), and padded with Perfectly Match Layers to avoid boundary reflections. Considering this domain, the equivalent frequency dependent dynamic stiffness and damping characteristics of the soil–foundation system are computed. For the second sub-system, the dynamic response of the structure under railway traffic is computed using a FE model with spring and dashpot elements at the support locations, which have the equivalent properties determined using the first sub-system. This soil–foundation–bridge model is solved using complex modal superposition, considering the equivalent dynamic stiffness and damping of the soil–foundation corresponding to each natural frequency. The proposed approach is then validated using both experimental measurements and an alternative Finite Element–Boundary Element (FE–BE) methodology. A strong match is found and the results discussed. [ABSTRACT FROM AUTHOR]

The expansion of the railway traffic during the last decades is considered as primary stage towards the evaluation of the remaining service life of the existing railway bridges. The objective of this paper is to review live loads, determination of fatigue damage and reliability index of the plate girder bridge. The assessment of the bridge has been made using Indian Standard code IS 800:2007, which is based on S-N curve approach. Data has been collected on train loads along a particular railway route and from the statistical analysis of the data, the representative train loads are identified which forms the load spectrum. The developed load spectrum is used to find the stress ranges and by applying S-N curve parameters, the damage calculation has been made and then the reliability index of the bridge is determined. [ABSTRACT FROM AUTHOR]

Diesel engine railway traffic causes atmosphere pollution due to the exhaust emission which may be harmful to the passengers as well as workers. In this study, the air quality and PM10 concentrations were evaluated around a railway station in Northeast India where trains are operated with diesel engines. The gaseous pollutant (e.g. SO2, NO2, and NH3) was collected and measured by using ultraviolet–visible spectroscopy. The advanced level characterizations of the PM10 samples were carried out by using ion chromatography, Fourier-transform infrared, X-ray diffraction, inductively coupled plasma optical emission spectrometry , X-ray photoelectron spectroscopy, field-emission scanning electron microscopy with energy-dispersive spectroscopy, and high-resolution transmission electron microscopy with energy-dispersive spectroscopy techniques to know their possible environmental contaminants. High-performance liquid chromatography technique was used to determine the concentration of polycyclic aromatic hydrocarbons to estimate the possible atmospheric pollution level caused by the rail traffic in the enclosure. The average PM10 concentration was found to be 262.11 µg m−3 (maximum 24 hour) which indicates poor air quality (AQI category) around the rail traffic. The statistical and air mass trajectory analysis was also done to know their mutual correlation and source apportionment. This study will modify traditional studies where only models are used to simulate the origins. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Contemporary History / Časopis za Suvremenu Povijest is the property of Croatia Institute for History and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hygiena is the property of Statni Zdravotni Ustav and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We propose a traffic flow and control model for the train dynamics in a linear metro line without junction. The model takes into account time constraints such as minimum interstation running times, minimum train dwell times at platforms, and minimum safe separation times between successive trains. Moreover, it includes a control law that sets the train dwell times at platforms based on the feedback of the train time-headways and of the passenger arrival rates at platforms. We show that the dynamic system converges to a stable stationary regime with a unique average growth rate, and derive, by numerical simulation, the traffic phases of the train dynamics. We compare the obtained traffic phases with the ones derived with an existing max-plus algebra traffic model, and derive the effect of the passenger travel demand on the train dynamics. Finally, we draw some conclusions and discuss perspectives of the proposed approach. [ABSTRACT FROM AUTHOR]

Railway transportation provides sustainable, fast and safe transport. Its attractiveness is linked to a broad concept of service reliability: the capability to adhere to a timetable in the presence of delays perturbing traffic. To counter these phenomena, real-time rescheduling can be used, changing train orders and times, according to rules of thumb, or mathematical optimization models, minimizing delays or maximizing punctuality. In the literature, different indices of robustness, reliability and resilience are defined for railway traffic. We review and evaluate these indices applied to railway traffic control, comparing optimal rescheduling approaches such as Open Loop and Closed Loop control, to a typical First-Come-First-Served dispatching rule, and following the timetable (no-action). This experimental analysis clarifies the benefits of automated traffic control for infrastructure managers, railway operators and passengers. The timetable order, normally used in assessing a-priori reliability, systematically overestimates unreliability of operations that can be reduced by real-time control. [ABSTRACT FROM AUTHOR]

The growth of density and circulation speed of railway transportation systems in urban areas increases the importance of the research issues of the produced environmental impacts. This study presents a field data analysis, obtained during monitoring campaigns of ground vibration, due to light railway traffic in urban areas, based on the artificial neural network (ANN) approach, using quantitative and qualitative predictors. Different ANN-based models, using those predictors, were evaluated/trained and validated. Using several criteria, including those that measures the possibility of ANN overfitting (RR2) and complexity (AIC), the best ANN model was successfully obtained for Lisbon area. This model, with 16 input elements (quantitative and qualitative predictors), 2 neurons on the hidden layer with a hyperbolic tangent sigmoid transfer function, and 1 neuron on the output layer considering a linear transfer function, has 0.9720 for the coefficient of determination and 0.5293 for the sum squared error. [ABSTRACT FROM AUTHOR]

Introduction: This paper describes an assessment of noise caused by railway traffic in a large high-loaded railway track in Northwest Slovakia.Materials and Methods: The measurements of noise levels generated by trains passing through residential neighborhoods were taken. Noise maps were also calculated showing noise pollution generated by the train traffic. In addition, the annoyance level and sleep disturbance of residents affected by railway noise were evaluated by a validated questionnaire on a pilot sample of 107 respondents living near the important railway track.Results: The measurements indicated that the noise levels generated by the passage of the train were extremely high especially at night, clearly exceeding the nighttime limits of equivalent sound pressure level established by the Decree of the Slovak Ministry of Health (No.549/2007) (LAeq = 55 dB). Measurements at one point during the night exceeded the limit values of up to 17.4 dB. The residents reported feeling affected by the noise generated by passing trains, which caused irritability, headache, poor concentration, and insomnia. In addition, 19.64% of the residents claimed that nocturnal noise pollution was the most distressing. The results of bivariate analysis showed a higher risk of annoyance especially for railway noise [ORMH = 7.80 (4.02-15.14)] and the noise from industry [ORMH = 3.08 (1.72-5.50)] in the exposed location.Discussion: The effects of railway traffic on annoyance/sleep and psychosocial well-being were evaluated in a few studies. In accordance with our results the railway noise mostly disturbs sleep and rest of the respondents.Conclusion: The pilot survey showed the importance of sleep and rest disturbance by railway noise and the possibilities of getting worse health condition in the future. Noise abatement measures and strategies should, therefore, be implemented in an effective and manageable way increasing the environmental advantages of rail transport. [ABSTRACT FROM AUTHOR]

The following study attempts to analyse an aspect of Czechoslovakian-German relations during the so called "Second Republic" (October 1938 - March 1939) that has until now stayed out of researchers' interests, namely the entries in the so-called station chronicles. This almost unknown source provides us a specific point of view on the atmosphere of the given period because of its combination of institutional and personal characteristics. The most focused part are the weeks in autumn 1938, when Czechoslovakia was forced to withdraw large parts of its area to Germany which led to massive and simultaneously chaotic changes that the railway transport had to react on. Extraordinary efforts were requested in both personal and freight traffic. The aim of the study is to consider these entries as lieu de mémoire and to find answers on following questions: Is it possible to read about the feelings of the people in these entries, or are they written strictly objectively? How are the Germans described, as enemies with no hope for future, or as colleagues suffering under the same circumstances? For the purpose of the study, chronicles both from border and inland regions have been used to detect eventual differences that might be compared as well. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Polytechnic Institute of Iasi - Construction & Architecture Section is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the increasing use of railway transportation, various methods have been developed for the control and management of train traffic. Train traffic control systems that are currently in use are overwhelmingly centralized systems. In this study, the development of the general structure of railway traffic control techniques is examined, centralized and decentralized control systems are investigated, and an alternative train traffic control system, the Decentralized Train Traffic Management System (DTMS), is suggested. Simulation results on the possible application of the proposed method to a railway line in South-East Turkey are employed to evaluate the performance of the developed system. [ABSTRACT FROM AUTHOR]

Simulation modelling is the efficient approach to analyse train traffic on a selected line or on a complex railway node. Simulation model uses an interaction between rail vehicles and infrastructure according to predefined procedures and timetable to compute parameters of train movement, track occupation, and capacity utilization. We propose a High-Level Petri Nets model that incorporates all interlocking and operating rules, infrastructure data, timetable and train delays data. In a Petri net environment, trains are tokens, track sections are places, and transitions are discrete events of train moving according to interlocking principles. Model has a hierarchy structure where each specific section is defined as a subsystem. Results from the simulation model are used to create reports on sections occupancy, train movement, for drawing of train's time-distance graphs, and for animation of train movement. Model is tested on the selected railway line for analyses of the denivelation of the junction in the Belgrade railway node. [ABSTRACT FROM AUTHOR]

In Finland, VR Group (the state-owned railway company) provides third-party logistics services (3PLs) for industrial customers. Their current static, single-objective optimization model does not support inter-enterprise collaboration to achieve optimal railway logistics. In this study, I introduce a collaborative decision-support method that can be applied to manage railway traffic under a scenario of increasing imports of Russian wood. Based on the data obtained to support this research, I describe railway traffic strategy scenarios in terms of 3PLs to account for the changed energy wood transportation and storage needs related to imported Russian wood. In the scenarios, the railway wagon rotation was adjusted to reach a globally optimal strategy that achieves efficient wood procurement logistics for the Finnish forest industry. These decisions were based on a comprehensive logistics analysis of the integrated wood demand and a supply chain model for southeastern Finland in the context of collaborative decision-making among members of the logistics chain. The model, which is based on dynamic multiple-objective linear programming, supports inter-enterprise collaboration because the adaptation of Russian wood imports to the regional railway transportation environment will require continuous, integrated optimization of the flows of wood and railway wagons. [ABSTRACT FROM PUBLISHER]

Purpose of the paper is to present a model for the railway traffic that consists of train arrivals and departures at different stations and also the passenger movement in stations, boarding trains and alighting at different destinations. This is a classic example of hybrid system for which initially the existing models are evaluated and the needs of model for this problem scenario are identified. The model proposed is utilized to simulate an experimental setup with the traffic based on the Train schedule and passenger flow in the stations to analyse whether it can work without any conflicts, impacts on passenger comforts, all in a single model. With this, we can determine the schedule of the train for an optimised headway time based on constrains for passenger waiting times and train running times. The simulation results are presented with assumed figures of passenger flow and train traffic. At the end, the optimization formulation is shown to arrive at an optimum schedule. [ABSTRACT FROM AUTHOR]

Copyright of Safety & Fire Technology / Bezpieczeństwo i Technika Pożarnicza is the property of Centrum Naukowo-Badawcze Ochrony Przeciwpozarowej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phenomenon of ground vibration amplification caused by railway traffic was found and proved. In order to study the reasons which cause the amplification, a drop-weight test was performed. Then, the model for both homogeneous and layered soil subjected to a harmonic vertical load was built. With the help of this model, displacement Green's function was calculated and the propagation laws of ground vibration responses were discussed. Results show that: 1) When applying a harmonic load on the half-space surface, the amplitude of ground vibrations attenuate with fluctuation, which is caused by the superposition of bulk and Rayleigh waves. 2) Vibration amplification can be enlarged under the conditions of embedded source and the soil layers. 3) In practice, the fluctuant attenuation should be paid attention to especially for the vibration receivers who are sensitive to single low frequencies (<10 Hz). Moreover, for the case of embedded loads, it should also be paid attention to that the receivers are located at the place where the horizontal distance is similar to embedded depth, usually 10 to 30 m for metro lines. [ABSTRACT FROM AUTHOR]

Due to the valid traffic policy and development strategy of the Republic of Slovenia, the Slovenian Railways have to consider the developmental and strategic aims of European railways. The perspective of progress is basically determined by skimming the European system development, by taking over the European system and managing the railway traffic in the connection with the European railway system. Technology and organization of the railway traffic system present the sum of all technological and organizational elements and processes that takes part in providing aims of the system. The aims are defined as solving transport problems in railway system. The term system is defined, from the formal mathematical viewpoint, as a whole that is usually complicated or even very much complicated. Therefore, the railway system is complex as well, and that is why it has to be managed precisely. In the narrow sense of meaning, technology and work organization both comprises a variety of means and procedures to realize basic activity that can be seen as a perfect unit, and that can be the process of passengers and freight transport in a transport system. Because of the prompt development of microelectronics and computer engineering, a new generation of electronic signal-safety devices appeared. All these changes from the past few years that have been introduced into railway technology, enable railway to become attractive and competitive to other means of traffic. Therefore, the Slovenian Railways have to follow novelties in traffic technology development and gradually modernize its railway network. [ABSTRACT FROM AUTHOR]

This study examines the effect of road and railway noise on property prices. It uses the hedonic regression technique on a Swedish data set that contains information about both road and railway noise for each property, and finds that road noise has a larger negative impact on the property prices than railway noise. This is in line with the evidence from the acoustical literature which has shown that individuals are more disturbed by road than railway noise, but contradicts recent results from a hedonic study on data of the United Kingdom. [ABSTRACT FROM AUTHOR]

In this paper, a general review is made on the problems of vibrations of the ground and nearby buildings induced by railway traffic, and on the researches on this subject in theoretical analyses, numerical simulations, and field experiments. The characteristics of ground vibrations induced by railway traffic and their propagation, from the aspects of duration, intensity distribution, vehicle load and speed, are summarized. The vibration influences on the daily life of people, the operation of high-tech devices and the safety of buildings, and the vibration properties of subsoil and buildings adjacent to the underground, ground and elevated railway systems are introduced. [ABSTRACT FROM AUTHOR]

In this paper, we present a weighted network model for the simulation of railway network. Here the stations and section tracks of the railway network are respectively regarded as the nodes and edges of the network model. Using the model proposed in this paper, we measure the distribution of trains and the mean waiting time of trains etc. The simulation results indicate that the proposed model can be successfully used for the simulation of railway network. Some phenomena observed in real railway networks can be reproduced, such as the characteristic behavior of train movement. A comparison with real data for the Netherlands (i.e., the Dutch railway network) is included. It supports the practical values of the proposed model. [ABSTRACT FROM AUTHOR]

A crucial step in measuring the resilience of railway infrastructure is to quantify the extent of its vulnerability to natural hazards. In this paper, we analyze the vulnerability of the German railway network to four types of natural hazards that regularly cause disruptions in German rail operations: floods, mass movements, slope fires, and tree falls. Using daily train traffic data matched with various data on disruptive events, we quantify the extent to which these four types of natural hazard reduce daily train traffic volumes. With a negative binomial count data regression, we find evidence that the track segments of the German railway network are most vulnerable to floods, followed by mass movements and tree-fall events. On average, floods reduce traffic on track segments by 19% of the average daily train traffic, mass movements by 16%, and tree fall by 4%. Moreover, when more than one type of natural hazard affects the track segment on the same day, train traffic on that segment falls by 34% of the average train traffic. Slope fires have an ambiguous and nonrobust effect on train traffic due to the reverse causality due to its triggering factors. This is the first study that attempts to rank different natural hazards according to their impact on railway traffic. The results have implications for the selection of resilience strategy and can help prioritize policy measures. [ABSTRACT FROM AUTHOR]