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Geranium robertianum is a herbaceous plant that prefers shady and fertile forest habitats. However, it also occurs on railway tracks, where there are difficult conditions for plant growth and regular herbicide spraying (in high concentrations, twice a year). One of the most commonly used herbicides in railway areas is glyphosate. The effect of the glyphosate on the G. robertianum plants found on railway tracks and in nearby forests in north-eastern Poland was checked. The aim of the study was to explain how G. robertianum can survive on railway tracks despite spraying with the glyphosate. Increased tolerance to the glyphosate of the G. robertianum plants from track populations was demonstrated compared to the plants from forest populations that had not previously been in contact with the herbicide. After 35 days after treatment with the herbicide, 75% of the plants from the observed forest populations withered, while only 38% did from the track populations. Ultrastructure of plant leaf cells from forest populations was strongly disturbed, which was not observed in plants from track populations. It was also shown that plants from track populations accumulated more glyphosate and AMPA in their tissues than plants from forest populations. The obtained results indicate that long-term use of herbicides may cause formation of biotypes of plants resistant to a given herbicide. This fact explains the possibility of G. robertianum occurring on railway tracks, despite spraying with the glyphosate. It is also a manifestation of microevolutionary processes. [ABSTRACT FROM AUTHOR]

Assuring an uninterrupted high Quality of Service (QoS) of railway communications between on-board terminals and base stations creates challenges for the provider. This is partly explained by the inherent mobility and the high penetration loss of carriages. Deploying mobile relays in public transportation is possible with a 100%-compatible LTE/EPC architecture. This effectively ensures that the electromagnetic insulation is kept to a minimum as QoS on board can be dramatically affected and worsened within the railway vehicles. Yet all users' traffic congregates via the radio backhaul link and needs to take into consideration the extra packet-overhead and signaling messages that as a general rule get transmitted via the fixed links. The paper's aim is to analyze the performance of mobile relays in loaded conditions comparing this to the standard direct mode. We propose an analytical model to compute the signaling rate. We parametrize it with experiments done on a testbed with real radio transmissions and show that signaling has no major impact on performance. We then evaluate the QoS experienced by passengers by means of simulations for two representative services: Web browsing and voice communications. The packet loss ratio for voice communications is reduced at the expense of a slight end-to-end latency increase thanks to mobile relays. During the high load conditions there is a significant reduction in the load time of a Web page and the throughput is increased. [ABSTRACT FROM AUTHOR]

While high-speed train systems have accelerated mobility in China during the twenty-first century, the train systems of normal speed have gradually been replaced and abandoned, resulting in a "rust belt" in some Chinese cities. The reuse of abandoned railways provides a way to rebuild urban public transit based on the traditional tracks, and is also a way to transform towards urban regeneration of the surrounding neighborhood. Previous studies discussed the possibilities of three perspectives of reusing the abandoned rails: as a new transportation route, as a place for tourism and commerce and as a green corridor for the public. As a case study, this paper selects Zhangjiakou City, which is the terminal of the first railway routes built by Chinese, and explores methods of transformation from rail to urban rail transit. Under the background of the Beijing Winter Olympics of 2022 being partly held in Zhangjiakou City, the old North station and a 10-km rail between the North and South Station have been abandoned since 2014. This paper suggests conversion of the railway into an urban tram to meet the increasing commuter flow between the old and new city center. Additionally, transformation of the abandoned railway located in the city center will also trigger the urban space regeneration by increasing more urban functions and promoting urban public space. This research might shed light on other cities with similar transforming transportation facilities by analyzing the reuse possibilities of Beijing-Zhangjiakou Railway in Zhangjiakou City. [ABSTRACT FROM AUTHOR]

In this research, we address the railway multiterritory dispatch planning (RMTDP) problem. The goal of the RMTDP problem is to find the optimal movement of trains across consecutive dispatch territories, and it is one of the major challenges that decision makers face on a daily basis. It ideally takes into account the correct placement of maintenance windows, remaining capacity of terminals, and availability of train crews, among other critical aspects such as locomotive balance, fueling locations, and inspections. Although these train movement plans are made at the corridor level, which comprises several dispatch territories, when it comes to execution, the meet–pass decisions are made at the individual dispatch territories. This notion causes disruptions and misalignment at the boundaries of dispatch territories. The approach in this paper aims at finding a holistic conflict-free master plan by optimally matching train lineups at territory boundaries and smoothly routing trains through bottlenecks. We propose an efficient solution approach that iteratively constructs a master scheduling plan while minimizing the amount of train delay within a given planning horizon. This is accomplished by designing a time–space network model to identify feasible schedules and developing a mathematical programming–based heuristic to solve the underlying model. A thorough computational study shows the effectiveness of our heuristic approach, as we report reasonable average run times of 3.0 and 6.5 minutes to solve instances of moderate to large size problems, respectively. The results obtained from the algorithm using test snapshots from a Class I railroad company have been shown to assistant chief dispatchers and have received encouraging feedback for applicability. [ABSTRACT FROM AUTHOR]

The railway handling area of the railway container terminal is the main place for container sea–rail transportation. To enhance the efficiency of the handling systems and improve the coordination of different types of equipment in railway handling area, an integrated scheduling model is developed, which integrates the scheduling of rail-mounted gantry cranes (GCs), inner trucks (ITs), and yard cranes (YCs). This model considers not only train loading and unloading simultaneously, but GC interference and safety margin, GC and YC travel time as well as buffer area. A multi-layer genetic algorithm (MLGA) is proposed to solve the problem. Eventually, comparison experiments are conducted, including the experiments on handling process between non-optimization and optimization, MLGA with and without the balanced operator and the performance of different numbers of ITs. These experiments validate that the model and algorithm is feasible and efficient in both equipment scheduling and allocation problem. [ABSTRACT FROM AUTHOR]

In this work we focus on an extension of the minimum cost flow problem in layered networks. Feasible arc flows must satisfy a specific compatibility restriction in addition to flow balance and capacity restrictions. Namely, at most one of the crossing arcs is allowed to have positive flow on it. This variant of the minimum cost flow problem, which we call the minimum cost noncrossing flow problem, can frequently be encountered in real life. The determination of optimal temporal quay crane allocations to berthed vessels in container terminals, and optimal train schedules through the stations on the same railroad line are two examples. We first analyze the complexity of the problem and show that the noncrossing flow problem is in fact N P -complete in a layered network. Then, we introduce mixed-integer linear programming formulations and discuss a polynomially solvable special case. Next we show a sufficient condition for the existence of a crossing in an optimal solution, which can be used for preprocessing the arcs in order to reduce the problem size. Our computational experiments on a large test set show that our preprocessing algorithm can significantly reduce the number of arcs. [ABSTRACT FROM AUTHOR]

Highlights • HFACS-RR useful tool for analysing operator signals passed at danger (SPAD) events. • Operator Acts associated with majority of SPADs reviewed. • Most common type of error associated with SPAD was contraventions and distraction. Abstract A common safety issue in the rail industry is a Signal Passed at Danger (SPAD) occurrence in which a train encroaches into a section of track without authority, usually by passing a signal at stop. This study aimed to analyse SPADs using the Human Factors Analysis and Classification System (HFACS) modified to suit the rail industry (HFACS-RR) to examine the human factors involved in the occurrences and identify trends. An analysis of an Australian freight rail organisation's investigation reports (N = 35) into SPADs was undertaken. The analysis revealed at least one HFACS-RR category for each of the events examined. It was found that 97.1% (n = 34) of the events had an 'operator act' category, with 74.3% associated with operator errors. Contraventions (e.g. violation of signal approach speed) and distraction (e.g. focus on other non-critical tasks) were the most common types of errors. Mitigation strategies to address these errors are discussed. These include a single methodology to investigate SPADs; train driver performance monitoring; and training strategies focussed on route knowledge, all of which have the potential to reduce SPADs and thereby minimise risk and improve safety. Future research into SPADs may include utilising a larger sample from various organisations, and examining potential differences in the frequency and types of errors of single versus two-man crewed trains. [ABSTRACT FROM AUTHOR]

In nearly saturated station areas the limited capacity is one of the main reasons of delay propagation. Spreading the trains well in time and space in these areas has a big impact on the passenger robustness, i.e. the total travel time in practice of all passengers in the railway network in case of frequently occurring small delays. We focus on improving the performance in the bottleneck of the network in order to improve the performance of the whole railway network. This paper proposes a method that builds from scratch a routing plan and a cyclic timetable that optimizes the infrastructure occupation and the passenger robustness. An integer linear routing model assigns, without considering a timetable, every train to a route such that the maximal node usage is minimized and that the number of times that each node is used, is quadratically penalized. Thereafter, a mixed integer linear timetabling model assigns to each train the blocking times at which the nodes on its route, assigned by the routing model, are reserved and released. Different from other approaches is that we focus on the occupation of the railway infrastructure before constructing the timetable. The approach is validated on the complex railway station area of Brussels (Belgium). Our routing plan and timetable from scratch improve the passenger robustness up to 11% compared to a reference timetable and routing plan composed by the Belgian railway infrastructure manager Infrabel and by up to 2% compared to a reference timetable and routing plan from literature. [ABSTRACT FROM AUTHOR]

The article presents the research results of economic feasibility of trains' breaking-up order control at marshalling yards. The article objective was to determine the area of rational use of trains' breaking-up order model, formalized in the form of stochastic programming problem. As a effectiveness criterion of trains' breaking-up order operating costs of marshalling yard were used, including the costs associated with cars' and locomotives' dwell time on the station and its approaches, as well as costs associated with additional shunting work. With the help of simulation modeling the dependence was obtained, describing the impact of trains' arrival forecasting error and processed car volumes on reducing operating costs of the marshalling yards through the trains' breaking-up order control. The studies enable us to establish the requirements for the accuracy of information support of operational planning tasks, which is necessary to achieve the desired economic effect of the trains' breaking-up order control. [ABSTRACT FROM AUTHOR]

The European railway market has gone through a period of liberalization over the last two decades. The liberalization of the railway market has also affected port-related railway transport. Efficient port-related transport chains are key in the competition among ports, however providing this efficiency is to a large extent a coordination challenge. Many forms of coordination are needed to ensure that the railway chain operates efficiently, including the bundling of cargo, and good organization between railway companies, terminal operators and the infrastructure managers to realize an efficient use of assets. From the literature, it appears that less attention has been paid to the economic organization of port-related railway transport in general, and specifically in the new liberalized institutional environment. The goal of this paper is to come up with a framework to better understand the issue of coordination in port-related railway chains in a liberalized institutional environment. This paper presents a conceptual framework rooted in Transaction Cost Economics (TCE). Based on an in-depth study into coordination in liberalized container railway market at the Port of Rotterdam, empirical illustrations are used to adjust the TCE approach toward a dynamic model influenced by Douglas North's theory on economic and institutional change. Empirics from the port of Rotterdam show that new players have entered the railway market and their role has changed. This paper shows that coordination of railway operations has become more complex after the regime change. From a port perspective, liberalization does not lead to an optimal allocation of resources in a process that is highly operationally interdependent. In the liberalized environment, coordination arrangements are necessary to enable efficient coordination of railway operations in Rotterdam. [ABSTRACT FROM PUBLISHER]

The present study aims to explore the psychophysiological impact of different traffic sounds in office spaces. In this experiment, 30 subjects were recruited and exposed to different traffic sounds in a virtual reality (VR) office scene. The road traffic sound and three railway sounds (conventional train, high-speed train, and tram) with three sound levels (45, 55, and 65 dB) were used as the acoustic stimuli. Physiological responses, electrodermal activity (EDA) and heart rate (HR) were monitored throughout the experiment. Psychological evaluations under each acoustic stimulus were also measured using scales within the VR system. The results showed that both the psychological and the physiological responses were significantly affected by the traffic sounds. As for psychological responses, considerable adverse effects of traffic sounds were observed, which constantly increased with the increase in the sound level. The peak sound level was found to have a better performance than the equivalent sound level in the assessment of the psychological impact of traffic sounds. As for the physiological responses, significant effects of both the acoustic factors (sound type and sound level) and the non-acoustic factors (gender and exposure time) were observed. The relationship between sound level and physiological parameters varied among different sound groups. The variation in sound level hardly affected the participants' HR and EDA when exposed to the conventional train and tram sounds. In contrast, HR and EDA were significantly affected by the levels of road traffic sound and high-speed train sound. Through a correlation analysis, a relatively weak correlation between the psychological evaluations and HR was found. [ABSTRACT FROM AUTHOR]

Although there is considerable engineering and demand planning analysis in the development of urban railways around the world, less attention is paid to the understanding of key operating conditions such as station stop times. The current paper takes forward research by London Underground, and shows that it is applicable to situations around the world without substantial changes in parameter values or the resulting passenger flow rates. Where passenger flow is substantially different, this can generally be explained by particular differences in the physical characteristics of the site, rolling stock, or passenger demand. [ABSTRACT FROM AUTHOR]

The location of rail transit lines and stations is a challenging problem because the number of possible alternatives is astronomical, the number of requirements and constraints is very large, and the evaluation of each alternative is based on numerous measures of effectiveness. Furthermore, large amounts of geographic information of many types are needed to compute some of the effectiveness measures. For instance, detailed spatial data on household locations and characteristics are needed to estimate accessibility to transit stations and the resulting access times and effects on demand. Detailed information on existing street networks, topography, and geology is needed to estimate construction costs and detailed information on land use and land values are needed to estimate right-of-way costs. In this paper we adapt the genetic algorithm and geographic information system approach to rail line optimization. Two types of costs are formulated and evaluated in the model: (1) operator cost which consists of track-related construction cost, station construction cost, right-of-way cost, earthwork cost, and rail operating cost; and (2) user cost which consists of access cost, riding time cost, and wait cost. The model is applied to a section of Anne Arundel County, Md., to reoptimize between a pair of stations an existing light rail transit line connecting Glen Burnie to the Baltimore Washington International Airport. The prototype model presented here produces very good alignments based on its criteria and can be extended to use far more comprehensive and complex evaluation functions. Additional factors and cost components that should be considered in more advanced models are also discussed. [ABSTRACT FROM AUTHOR]

This paper describes the hump sequencing component of the Terminal Priority Movement Planner (TPMP), a proof-of-concept decision support system field tested in 1994 at Union Pacific Railroad's Hinkle, Oregon, classification yard. The goal was not to make all connections, but to ensure that at least a subset of the most important ones— those which would cause late deliveries if missed—were protected. Rather than automatically dropping late connections, TPMP minimizes delays associated with holding outbound trains as necessary to protect connections. A human being, not the computer, makes the decision when it is necessary to drop a late inbound connection and leave cars behind. A mixed integer, nonlinear mathematical programming problem is solved using breadth-first branch and bound search. Realistic one-day problems are solved in 15-20 seconds on a small microcomputer. Practical adaptations required to implement the procedure in a real world setting are also described. Considerable emphasis is given to discussion of factors affecting rail service reliability, and steps railroad management can take to improve performance. [ABSTRACT FROM AUTHOR]

The information for this article was prepared by Frank R. Harder, president of the Tioga Group, for the Eno Transportation Foundation's policy forum titled "Improving Metropolitan Planning to Integrate Freight Transportation," held on October 20, 1998, in Washington, DC. The forum addressed ways to enhance the competitiveness of intermodal freight transportation through regional land use and transportation planning decisions, while also encouraging the sound development of metropolitan areas. As part of the forum process, papers are commissioned to provide participants with more detailed descriptions of the issues involved. The information in this article was extracted from a paper providing an overview of the factors that drive private-sector decisions regarding the location and placement of freight transportation facilities and manufacturing or distribution centers. Factors such as the relative importance of proximity to traffic generators for certain markets, distribution costs, and the quality of regional transportation infrastructure are assessed. [ABSTRACT FROM AUTHOR]

Any study of rail freight service or freight car utilization must eventually address the reliability of train connection performance. In a series of case studies over the past 10 years, the MIT Rail Group developed PMAKE analysis as an effective means of doing this. The PMAKE methodology has been used extensively in service planning by a number of railroads and has been used in two major rail network models. The Freight Car Utilization Program has supported two demonstration projects showing how to incorporate PMAKE analysis in railroad terminal control systems. The paper reviews three other major modeling approaches used in rail yard studies: simulation, queuing, and capacity planning. These approaches have had limited effectiveness in prediction train connection performance and in supporting management control systems. PMAKE analysis improves upon these approaches by making it easier to (a) calibrate models of yard performance and (b) incorporate analytic techniques within the operating control system. In short, PMAKE analysis builds a bridge between operations research technique and management control. The paper includes the parameters of PMAKE functions calibrated for various rail yards. It also includes the mathematical basis for PMAKE analysis and shows several means of calibrating PMAKE functions. This paper, therefore, provides a complete description of PMAKE analysis, including its development, its relation to other methods of terminal analysis and its use by the rail industry. [ABSTRACT FROM AUTHOR]

The article reports on the architectural features of a railway station erected in the Netherlands. The author argues that the railway station was constructed is such a way as to depart from the conventional image of railway stations. The shift in design was due in part to the enlightenment acquired by engineers at the Netherlands Railways Architects.