WorldWideScience

Sample records for mathematical railway network

  1. Network effects in railways

    DEFF Research Database (Denmark)

    Landex, Alex

    2012-01-01

    Railway operation is often affected by network effects as a change in one part of the network can influence other parts of the network. Network effects occur because the train runs may be quite long and since the railway system has a high degree of interdependencies as trains cannot cross....../overtake each other everywhere in the network. First this paper describes network effects in general (section 1). In section 2 the network effects for trains and how they can be measured by scheduled waiting time is described. When the trains are affected by network effects the passengers are also affected....... Therefore, sections 3 and 4 describe the network effects for passengers and how they can be measured using passenger delay models. Before the concluding remarks in section 6, section 5 discusses how the operation can be improved by examining network effects in the planning process. © 2012 WIT Press....

  2. The Network effects of Railway Investments

    DEFF Research Database (Denmark)

    Hansen, Sten; Landex, Alex; Kaas, Anders H.

    2006-01-01

    Network effects is when a change at one place in the railway network results in changes elsewhere in the network – maybe even far away from the original change. Railway investments have network effects, and therefore, this paper describes the network effects and how these network effects can...

  3. Real-time Railway Traffic Management : Dispatching in complex, large and busy railway networks

    NARCIS (Netherlands)

    Corman, F.

    2010-01-01

    Railway is an important and sustainable transportation mode, which despite good potentials results in a limited attractiveness, mostly due to the perceived consequences of unreliability. In fact, busy railway networks with frequent and heterogeneous services are highly sensitive to delay

  4. An Improved Walk Model for Train Movement on Railway Network

    International Nuclear Information System (INIS)

    Li Keping; Mao Bohua; Gao Ziyou

    2009-01-01

    In this paper, we propose an improved walk model for simulating the train movement on railway network. In the proposed method, walkers represent trains. The improved walk model is a kind of the network-based simulation analysis model. Using some management rules for walker movement, walker can dynamically determine its departure and arrival times at stations. In order to test the proposed method, we simulate the train movement on a part of railway network. The numerical simulation and analytical results demonstrate that the improved model is an effective tool for simulating the train movement on railway network. Moreover, it can well capture the characteristic behaviors of train scheduling in railway traffic. (general)

  5. Railway track circuit fault diagnosis using recurrent neural networks

    NARCIS (Netherlands)

    de Bruin, T.D.; Verbert, K.A.J.; Babuska, R.

    2017-01-01

    Timely detection and identification of faults in railway track circuits are crucial for the safety and availability of railway networks. In this paper, the use of the long-short-term memory (LSTM) recurrent neural network is proposed to accomplish these tasks based on the commonly available

  6. Characteristics of suicide hotspots on the Belgian railway network.

    Science.gov (United States)

    Debbaut, Kevin; Krysinska, Karolina; Andriessen, Karl

    2014-01-01

    In 2004, railway suicide accounted for 5.3% of all suicides in Belgium. In 2008, Infrabel (Manager of the Belgian Railway Infrastructure) introduced a railway suicide prevention programme, including identification of suicide hotspots, i.e., areas of the railway network with an elevated incidence of suicide. The study presents an analysis of 43 suicide hotspots based on Infrabel data collected during field visits and semi-structured interviews conducted in mental health facilities in the vicinity of the hotspots. Three major characteristics of the hotspots were accessibility, anonymity, and vicinity of a mental health institution. The interviews identified several risk and protective factors for railway suicide, including the training of staff, introduction of a suicide prevention policy, and the role of the media. In conclusion, a comprehensive railway suicide prevention programme should continuously safeguard and monitor hotspots, and should be embedded in a comprehensive suicide prevention programme in the community.

  7. Auction pricing of network access for North American railways

    DEFF Research Database (Denmark)

    Harrod, Steven

    2013-01-01

    The question of pricing train paths for "open access" railway networks in North America is discussed. An auction process is suggested as necessary to maintain transparency in the contracting process. Multiple random samples of auction pricing for a single track railway line demonstrate...... that the infrastructure entity will receive approximately 15.6% less than the true value of the contracted train paths. This loss of revenue threatens the objective of reducing government subsidy for the railway network. (C) 2012 Elsevier Ltd. All rights reserved....

  8. THE EVALUATION OF THE EFFECT OF REACTIVE POWER COMPENSATION IN ELECTRIC POWER LOSSES IN ELECTRIC NETWORK OF RAILWAY JUNCTION

    OpenAIRE

    O. I. Bondar; I. L. Bondar

    2009-01-01

    In this work the generalized mathematical model of an electrical network of the electrified railway junction is proposed. An estimation of influence of static var compensators installation on electric power losses in a network is executed on the basis of given model.

  9. High-Speed Railways and Urban Networks in China

    NARCIS (Netherlands)

    Yang, Haoran

    2018-01-01

    Worldwide, High-Speed Railway (HSR) networks have been developed intensely over the last few decades, such as Tokyo-Osaka, the first HSR corridor in Japan, the TGV in France and the ICE in Germany. HSR has also experienced exponential growth in China so that currently China’s HSR networks are the

  10. HIGH SPEED RAILWAY LINES – FUTURE PART OF CZECH RAILWAY NETWORK?

    Directory of Open Access Journals (Sweden)

    Lukáš Týfa

    2017-08-01

    Full Text Available The paper first describes high speed rail generally and explains the relationship between high speed and conventional railway networks (according to the vehicle types in operation on the network. The core of the paper is comprised of the methodology for choosing the best route for a railway line and its application to the high speed railway connection Praha – Brno. The Algorithm used assumes the existence of more route proposals, which could be different in terms of the operational conception, line routing or types of vehicles used. The optimal variant is the one with the lowest daily cost, which includes infrastructure and vehicle costs; investment and operational costs. The results from applying this model confirmed the assumption, that a dedicated high speed railway line, only for high speed trains, has the same or lower investment costs than a line for both high speed and conventional trains. Furthermore, a dedicated high line also has a lower cost for infrastructure maintenance but a higher cost for buying high speed multiple units.

  11. Developing noise control strategies for entire railway networks

    Science.gov (United States)

    Oertli, Jakob

    2006-06-01

    The EU Environmental Noise Directive (2002/49) requires member states to deliver noise maps to the commission by 2007 and action plans by 2008 both for agglomerations as well as for major roads, railways and airports. Noise mitigation projects resulting from action plans are usually very expensive and therefore may threaten the economic viability of the railways in the current harsh competitive transport market, thus hindering sustainable transport policies. It is therefore of vital interest that the action plans and the resulting projects are designed in the most cost-effective way possible. The EU and Union of Railways (UIC) sponsored project Strategies and Tools to Assess and Implement noise Reducing measures for Railway Systems (STAIRRS) recognized this need and developed a tool, with which such optimal solutions can be obtained for entire railway networks. Since data collection is the most expensive part of the analysis, noise mapping data is ideally collected in such a way that it can be used for the calculation of the different scenarios, from which the most cost-effective action plans are chosen. The paper shows how the STAIRRS tool is used for this purpose and how cost-effectiveness considerations have led to optimal railway noise mitigation strategies in Switzerland and have given a basis for noise related decision making in Luxembourg.

  12. Railway bogie vibration analysis by mathematical simulation model and a scaled four-wheel railway bogie set

    Science.gov (United States)

    Visayataksin, Noppharat; Sooklamai, Manon

    2018-01-01

    The bogie is the part that connects and transfers all the load from the vehicle body onto the railway track; interestingly the interaction between wheels and rails is the critical point for derailment of the rail vehicles. However, observing or experimenting with real bogies on rail vehicles is impossible due to the operational rules and safety concerns. Therefore, this research aimed to develop a vibration analysis set for a four-wheel railway bogie by constructing a four-wheel bogie with scale of 1:4.5. The bogie structures, including wheels and axles, were made from an aluminium alloy, equipped with springs and dampers. The bogie was driven by an electric motor using 4 round wheels instead of 2 straight rails, with linear velocity between 0 to 11.22 m/s. The data collected from the vibration analysis set was compared to the mathematical simulation model to investigate the vibration behavior of the bogie, especially the hunting motion. The results showed that vibration behavior from a scaled four-wheel railway bogie set significantly agreed with the mathematical simulation model in terms of displacement and hunting frequency. The critical speed of the wheelset was found by executing the mathematical simulation model at 13 m/s.

  13. Capacity gain with an alternative LTE railway communication network

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José

    2014-01-01

    , such as 3GPP Long Term Evolution (LTE). T his paper describe s how to adapt the reversible multi - chain/channel queuing system to model an LTE cell serving ETCS - equipped trains . It is proposed to use the multiple user chains available in the model to represent varying bitrate in LTE radio access network....... Usin g this model , LTE and GSM - R are compare d in terms of capacity on an example at Copenhagen Main Train Station . The purpose of this work is to demonstrate the benefits that railway operators and infrastructure managers can expect from the introduc tion of LTE , as a telecommunication technology...... Control System (ETCS) signaling , the capacity of GSM - R turns out to be insufficient . GSM - R cannot ful fill the railway requirements , in terms of the number of simultaneous ETCS connections . This is why , alternative , more efficient communication technologies should be considered by railways...

  14. Growth of Railway Network in China (1988-2002

    Directory of Open Access Journals (Sweden)

    Serguei Tarkhov

    2003-05-01

    Full Text Available 20. 000 km of new railways were built in China in1988-2002. The railway network has increased its topologicalcomplexity from 75 to 112 circuits and the new 3nt topologicallayer appeared in 1993 and the 4'h will emerge in 2004 after the opening of the rail ferry Dalian - Yan-tai. The main features ofthe recent Chinese rail network are: 1 the predominance ofmeridional-ity, 2 the spatial disproportion between the easterncoastal area (with dense network and the empty western part,3 the low level of electrification (20% and the low share ofdouble-track sections (30%, 4 the land-lock orientation ofthe whole network and a small number of lines along the seacoasts. These disproportions are the main obstacles for a harmonicspatial devel-opment of the economic structure.

  15. Evaluation of ETCS performance with LTE as alternative railway communication network using OPNET

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José

    2013-01-01

    GSM-Railways (GSM-R) is a communication mobile network designed to fulfill specific communication needs of railways. GSM-R is being widely deployed across Europe and other countries around the world for providing railway voice and train control services (ETCS). Despite that, GSM-R already shows...

  16. Risk Evaluation of Railway Coal Transportation Network Based on Multi Level Grey Evaluation Model

    Science.gov (United States)

    Niu, Wei; Wang, Xifu

    2018-01-01

    The railway transport mode is currently the most important way of coal transportation, and now China’s railway coal transportation network has become increasingly perfect, but there is still insufficient capacity, some lines close to saturation and other issues. In this paper, the theory and method of risk assessment, analytic hierarchy process and multi-level gray evaluation model are applied to the risk evaluation of coal railway transportation network in China. Based on the example analysis of Shanxi railway coal transportation network, to improve the internal structure and the competitiveness of the market.

  17. A hierarchical network modeling method for railway tunnels safety assessment

    Science.gov (United States)

    Zhou, Jin; Xu, Weixiang; Guo, Xin; Liu, Xumin

    2017-02-01

    Using network theory to model risk-related knowledge on accidents is regarded as potential very helpful in risk management. A large amount of defects detection data for railway tunnels is collected in autumn every year in China. It is extremely important to discover the regularities knowledge in database. In this paper, based on network theories and by using data mining techniques, a new method is proposed for mining risk-related regularities to support risk management in railway tunnel projects. A hierarchical network (HN) model which takes into account the tunnel structures, tunnel defects, potential failures and accidents is established. An improved Apriori algorithm is designed to rapidly and effectively mine correlations between tunnel structures and tunnel defects. Then an algorithm is presented in order to mine the risk-related regularities table (RRT) from the frequent patterns. At last, a safety assessment method is proposed by consideration of actual defects and possible risks of defects gained from the RRT. This method cannot only generate the quantitative risk results but also reveal the key defects and critical risks of defects. This paper is further development on accident causation network modeling methods which can provide guidance for specific maintenance measure.

  18. Analyzing the causation of a railway accident based on a complex network

    Science.gov (United States)

    Ma, Xin; Li, Ke-Ping; Luo, Zi-Yan; Zhou, Jin

    2014-02-01

    In this paper, a new model is constructed for the causation analysis of railway accident based on the complex network theory. In the model, the nodes are defined as various manifest or latent accident causal factors. By employing the complex network theory, especially its statistical indicators, the railway accident as well as its key causations can be analyzed from the overall perspective. As a case, the “7.23” China—Yongwen railway accident is illustrated based on this model. The results show that the inspection of signals and the checking of line conditions before trains run played an important role in this railway accident. In conclusion, the constructed model gives a theoretical clue for railway accident prediction and, hence, greatly reduces the occurrence of railway accidents.

  19. Analyzing the causation of a railway accident based on a complex network

    International Nuclear Information System (INIS)

    Ma Xin; Li Ke-Ping; Luo Zi-Yan; Zhou Jin

    2014-01-01

    In this paper, a new model is constructed for the causation analysis of railway accident based on the complex network theory. In the model, the nodes are defined as various manifest or latent accident causal factors. By employing the complex network theory, especially its statistical indicators, the railway accident as well as its key causations can be analyzed from the overall perspective. As a case, the “7.23” China—Yongwen railway accident is illustrated based on this model. The results show that the inspection of signals and the checking of line conditions before trains run played an important role in this railway accident. In conclusion, the constructed model gives a theoretical clue for railway accident prediction and, hence, greatly reduces the occurrence of railway accidents. (interdisciplinary physics and related areas of science and technology)

  20. Mathematical model of optimal empty rail car distribution at railway transport nodes

    Directory of Open Access Journals (Sweden)

    Aleksandr RAKHMANGULOV

    2014-09-01

    Full Text Available At present there are two trends in the market of rail freight transportation in Russia: freight owners put forward higher demands to the transportation quality (promptness of delivery in an effort to reduce storage costs by means of reducing the size of freight shipment; the structure of railcar traffic volume of the railways of Russia is getting more complex due to the reduction of the average shipment size and due to the transfer of railcar fleet ownership to a large number of operating companies. These trends significantly complicate operational management supervision of railway stations and transport nodes. Application of typical data from the information system about the railcar location at the transportation node is not enough for the dispatchers to make the best decision concerning the car traffic management. The dispatcher traffic control service needs some software-based models of efficient railcar distribution. The article is concerned with the description and development of the mathematical model of empty railcar distribution for loading at the railway transport node; this model will take into account the requirements of railcar owners in terms of their cars application, the operating work level of railroad stations of the transportation node and the possibility of adding the groups of empty railcars to the transfer trains, clean-up trains and industrial railway trains operating on a tight schedule. The developed model and the software package were implemented in the information system of the industrial railway of the major metallurgical enterprise - OJSC «Magnitogorsk Metallurgical Works», which processes up to two thousand of railcars belonging to different owners. This model made it possible to reduce the labour intensity of dispatcher operation planning the empty railcar distribution for loading and reduce the total time the railcars spend in the enterprise railway system.

  1. Intelligent condition monitoring of railway catenary systems : A Bayesian Network approach

    NARCIS (Netherlands)

    Wang, H.; Nunez Vicencio, Alfredo; Dollevoet, R.P.B.J.; Liu, Zhigang; Chen, Junwen; Spiryagin, Maksym; Gordon, Timothy; Cole, Colin; McSweeney, Tim

    2017-01-01

    This study proposes a Bayesian network (BN) dedicated for the intelligent condition monitoring of railway catenary systems. It combines five types of measurements related to catenary condition, namely the contact wire stagger, contact wire height, pantograph head displacement, pantograph head

  2. Mathematical model for estimating of technical and technological indicators of railway stations operation

    Directory of Open Access Journals (Sweden)

    D.M. Kozachenko

    2013-06-01

    Full Text Available Purpose. The article aims to create a mathematical model of the railway station functioning for the solving of problems of station technology development on the plan-schedule basis. Methodology. The methods of graph theory and object-oriented analysis are used as research methods. The model of the station activity plan-schedule includes a model of technical equipment of the station (plan-schedule net and a model of the station functioning , which are formalized on the basis of parametric graphs. Findings. The presented model is implemented as an application to the graphics package AutoCAD. The software is developed in Visual LISP and Visual Basic. Taking into account that the construction of the plan-schedule is mostly a traditional process of adding, deleting, and modifying of icons, the developed interface is intuitively understandable for a technologist and practically does not require additional training. Originality. A mathematical model was created on the basis of the theory of graphs and object-oriented analysis in order to evaluate the technical and process of railway stations indicators; it is focused on solving problems of technology development of their work. Practical value. The proposed mathematical model is implemented as an application to the graphics package of AutoCAD. The presence of a mathematical model allows carrying out an automatic analysis of the plan-schedule and, thereby, reducing the period of its creation more than twice.

  3. RISK VIP: Evaluation of Flood Risk on the French Railway Network Using an Innovative GIS Approach

    Directory of Open Access Journals (Sweden)

    Cheetham Mark

    2016-01-01

    Full Text Available Flooding can have significant direct and indirect negative effects on a railway network affecting both infrastructure and rail operations. Such impacts include the delaying or cancelling of train services, damage to railway structures or the implementation of costly maintenance and monitoring programs to ensure the safety and performance of the railway system. Identifying sections of railway line at risk from flooding allows appropriate actions to be targeted at specific areas and contributes to an effective asset management plan. Flooding of railway infrastructure can have numerous sources including surface water run-off, insufficient capacity of hydraulic structures or the inundation of embankments located in floodplains. Consequences of flooding include the destabilisation of structures (surface erosion of embankments or the undermining of bridge foundations, differential settlement of structures and damage to the track structure. This paper details an innovative approach developed at the SNCF using a Geographic Information System (GIS model to identify zones of the railway network at risk of different types of flooding. The GIS model RiskVIP has been constructed through the assessment of three distinct components of risk: “Vulnerability” (assessment of the susceptibility of the railway infrastructure to flood conditions, Intensity’ (capacity of a catchment to generate a flood flow, Probability’ (probability of a rainfall event.Through the application of decision trees, the component ‘Intensity’ has been characterised in the model by the physical properties of the catchment intercepted by the railway line (surface area of the catchment, slope and land cover characteristics and “Vulnerability” by the infrastructure itself (type, geometry and the presence of hydraulic structures. In order to evaluate its efficiency at identifying sites at risk of flooding, the model has been tested in the region of Languedoc-Roussillon in France

  4. Impact of the traffic load on performance of an alternative LTE railway communication network

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José

    2013-01-01

    communication infrastructure supporting railway signaling. This work is based on OPNET realistic network simulations, which show the relation between the traffic load (the number of trains transmitting and receiving data in an LTE cell) and the delay performance of the European Train Control System (ETCS......Although many countries only now begin to invest in deployment of GSM-Railways (GSM-R) networks, this technology is already obsolete and reveals its significant shortcomings. The most troublesome one is the insufficient number of communication channels offered by GSM-R. This is a major problem...... obstructing railway operations at big train stations and junctions. Hence, other technologies, such as Long Term Evolution (LTE), need to be considered as an alternative to GSM-R. The goal of this paper is to demonstrate the capacity increase that railways can expect, from the introduction of LTE as internal...

  5. [Emergency response management near the tracks of the public railway network: special aspects of missions connected with the German national railway system].

    Science.gov (United States)

    Krämer, P; Aul, A; Vock, B; Frank, C

    2010-11-01

    Emergency response management and rescue operations concerning the railway network in Germany need special attention and implementation in several ways. The emergency response concerning the German national railway network managed by Deutsche Bahn AG is subject to various rules and regulations which have to be followed precisely. Only by following these rules and procedures is the safety of all emergency staff at the scene ensured. The German national railway network (Deutsche Bahn AG) provides its own emergency response control center, which specializes in managing its response to emergencies and dispatches an emergency response manager to the scene. This person serves as the primary Deutsche Bahn AG representative at the scene and is the only person who is allowed to earth the railway electrical power lines. This article will discuss different emergency situations concerning railway accidents and the emergency medical response to them based on a near collision with a high speed train during a rescue mission close to the railway track. Injury to personnel could only be avoided by chance and luck. The dangers and risks for rescue staff are specified. Furthermore, the article details practical guidelines for rescue operations around the German national railway track system.

  6. THE BASIS OF MATHEMATICAL DESCRIPTION FOR WAVE MODEL OF STRESSES PROPAGATION IN RAILWAY TRACK

    Directory of Open Access Journals (Sweden)

    D. M. Kurhan

    2016-10-01

    Full Text Available Purpose. Modern scientific research has repeatedly cited practical examples of the dynamic effects of railway track operation that go beyond the static calculation schemes. For the track sections where the train speed is approaching to the velocity of wave propagation in the slab track layers such issues are of particular relevance. An adequate tool for the study of such issues can be the use of the wave theory of stress propagation. The purpose of the article is the creation of a mathematical description of the basic principles of the stress propagation wave model in the railway track, which can be used as a basis for the practical development of the relevant calculation system. Methodology. The model of stress-strain states of the railway track on the basis of the stress wave propagation theory is to bring together the equations of the geometry of the outline of the space systems that is involved in the interaction at a given time, and the dynamic equilibrium equations of deformation. The solution is based on the use of the laws of the theory of elasticity. The wave front is described by an ellipsoid equation. When determining the variation in time of the surface position of the ellipsoid a vector approach is used. Findings. The geometry equations of the wave motion determine the volumes of material layers of the slab track involved in the interaction at a given time. The dynamic equilibrium determination of the deformed condition of the space bounded by the wave front makes it possible to calculate both the stresses and strains, and their changes during the time of the load perception. Thus, mathematical descriptions of the processes that occur in the perception of the load by the elements of railway track at high speeds were obtained. Originality. The simulation tasks of the track and rolling stock interaction, in particular taking into account the dynamic deflection of slab track were further developed. For the first time the article

  7. Mathematical Modelling Plant Signalling Networks

    KAUST Repository

    Muraro, D.; Byrne, H.M.; King, J.R.; Bennett, M.J.

    2013-01-01

    methods for modelling gene and signalling networks and their application in plants. We then describe specific models of hormonal perception and cross-talk in plants. This mathematical analysis of sub-cellular molecular mechanisms paves the way for more

  8. Optimal Path Choice in Railway Passenger Travel Network Based on Residual Train Capacity

    Directory of Open Access Journals (Sweden)

    Fei Dou

    2014-01-01

    Full Text Available Passenger’s optimal path choice is one of the prominent research topics in the field of railway passenger transport organization. More and more different train types are available, increasing path choices from departure to destination for travelers are unstoppable. However, travelers cannot avoid being confused when they hope to choose a perfect travel plan based on various travel time and cost constraints before departure. In this study, railway passenger travel network is constructed based on train timetable. Both the generalized cost function we developed and the residual train capacity are considered to be the foundation of path searching procedure. The railway passenger travel network topology is analyzed based on residual train capacity. Considering the total travel time, the total travel cost, and the total number of passengers, we propose an optimal path searching algorithm based on residual train capacity in railway passenger travel network. Finally, the rationale of the railway passenger travel network and the optimal path generation algorithm are verified positively by case study.

  9. Road and railway network of the Paks nuclear power plant, Hungary

    International Nuclear Information System (INIS)

    Szoukup, I.; Komlos, Cs.

    1983-01-01

    Meeting the demands of reception, unloading and transportation of materials during the construction and later, during the operation of the plant, is ensured by a suitable road and railway network. The tasks of internal roads and tracks, their connection with the national transportation network are presented. (author)

  10. Robustness indicators and capacity models for railway networks

    DEFF Research Database (Denmark)

    Jensen, Lars Wittrup

    In a world continuous striving for higher mobility and the use of more sustainable modes of transport, there is a constant pressure on utilising railway capacity better and, at the same time, obtaining a high robustness against delays. During the planning of railway operations and infrastructure ....... This has motivated the research conducted and described in this thesis, where the objective has been to develop and improve existing methods to achieve timetable and infrastructure plans with robust capacity utilisation aimed at the strategic and early tactical planning phases....

  11. Assessment of Stochastic Capacity Consumption in Railway Networks

    DEFF Research Database (Denmark)

    Jensen, Lars Wittrup; Landex, Alex; Nielsen, Otto Anker

    2015-01-01

    The railway industry continuously strive to reduce cost and utilise resources optimally. Thus, there is a demand for tools that are able to fast and efficiently provide decision-makers with solutions that can help them achieve their goals. In strategic planning of capacity, this translates...

  12. A Complex Network Model for Analyzing Railway Accidents Based on the Maximal Information Coefficient

    International Nuclear Information System (INIS)

    Shao Fu-Bo; Li Ke-Ping

    2016-01-01

    It is an important issue to identify important influencing factors in railway accident analysis. In this paper, employing the good measure of dependence for two-variable relationships, the maximal information coefficient (MIC), which can capture a wide range of associations, a complex network model for railway accident analysis is designed in which nodes denote factors of railway accidents and edges are generated between two factors of which MIC values are larger than or equal to the dependent criterion. The variety of network structure is studied. As the increasing of the dependent criterion, the network becomes to an approximate scale-free network. Moreover, employing the proposed network, important influencing factors are identified. And we find that the annual track density-gross tonnage factor is an important factor which is a cut vertex when the dependent criterion is equal to 0.3. From the network, it is found that the railway development is unbalanced for different states which is consistent with the fact. (paper)

  13. Past and future of a regional railway network in Mezohegyes (Hungary area

    Directory of Open Access Journals (Sweden)

    Brigitta ZSOTER

    2011-01-01

    Full Text Available The role of railway network in the internal passenger and heavy traffic is continuously decreasing. Regarding the number of passengers, proportion of the railway out of the internal passenger transport was more than 20% less in 2000. The railway passenger transportation suffered a setback in shorter distances in the last decades. In case of railway transportation of goods both the carriage distance and the quantity of goods have decreased. Content of the load has changed, too. Comparing to the previous one, quantity of the transported building materials, metal waste, ores and coal etc. lessened. In contrast with it proportion of agricultural products, machines has increased. It is worth examining the changes in connection with the passenger and heavy traffic in the last few years not only in country level but in the level of several settlements, as well. In settlements’ life a transportation route of the infrastructural sphere plays an important role. In this essay it is aiming to examine the changes in railway traffic of town Mezohegyes, a settlement on the Southern part of the Hungarian Plain, between 1990 and 2006. Research work of this kind has been carried out about town Mezohegyes earlier.

  14. Analysis and forecast of railway coal transportation volume based on BP neural network combined forecasting model

    Science.gov (United States)

    Xu, Yongbin; Xie, Haihong; Wu, Liuyi

    2018-05-01

    The share of coal transportation in the total railway freight volume is about 50%. As is widely acknowledged, coal industry is vulnerable to the economic situation and national policies. Coal transportation volume fluctuates significantly under the new economic normal. Grasp the overall development trend of railway coal transportation market, have important reference and guidance significance to the railway and coal industry decision-making. By analyzing the economic indicators and policy implications, this paper expounds the trend of the coal transportation volume, and further combines the economic indicators with the high correlation with the coal transportation volume with the traditional traffic prediction model to establish a combined forecasting model based on the back propagation neural network. The error of the prediction results is tested, which proves that the method has higher accuracy and has practical application.

  15. Comparisons of complex network based models and real train flow model to analyze Chinese railway vulnerability

    International Nuclear Information System (INIS)

    Ouyang, Min; Zhao, Lijing; Hong, Liu; Pan, Zhezhe

    2014-01-01

    Recently numerous studies have applied complex network based models to study the performance and vulnerability of infrastructure systems under various types of attacks and hazards. But how effective are these models to capture their real performance response is still a question worthy of research. Taking the Chinese railway system as an example, this paper selects three typical complex network based models, including purely topological model (PTM), purely shortest path model (PSPM), and weight (link length) based shortest path model (WBSPM), to analyze railway accessibility and flow-based vulnerability and compare their results with those from the real train flow model (RTFM). The results show that the WBSPM can produce the train routines with 83% stations and 77% railway links identical to the real routines and can approach the RTFM the best for railway vulnerability under both single and multiple component failures. The correlation coefficient for accessibility vulnerability from WBSPM and RTFM under single station failures is 0.96 while it is 0.92 for flow-based vulnerability; under multiple station failures, where each station has the same failure probability fp, the WBSPM can produce almost identical vulnerability results with those from the RTFM under almost all failures scenarios when fp is larger than 0.62 for accessibility vulnerability and 0.86 for flow-based vulnerability

  16. Mathematical Formulation of Multilayer Networks

    Science.gov (United States)

    De Domenico, Manlio; Solé-Ribalta, Albert; Cozzo, Emanuele; Kivelä, Mikko; Moreno, Yamir; Porter, Mason A.; Gómez, Sergio; Arenas, Alex

    2013-10-01

    A network representation is useful for describing the structure of a large variety of complex systems. However, most real and engineered systems have multiple subsystems and layers of connectivity, and the data produced by such systems are very rich. Achieving a deep understanding of such systems necessitates generalizing “traditional” network theory, and the newfound deluge of data now makes it possible to test increasingly general frameworks for the study of networks. In particular, although adjacency matrices are useful to describe traditional single-layer networks, such a representation is insufficient for the analysis and description of multiplex and time-dependent networks. One must therefore develop a more general mathematical framework to cope with the challenges posed by multilayer complex systems. In this paper, we introduce a tensorial framework to study multilayer networks, and we discuss the generalization of several important network descriptors and dynamical processes—including degree centrality, clustering coefficients, eigenvector centrality, modularity, von Neumann entropy, and diffusion—for this framework. We examine the impact of different choices in constructing these generalizations, and we illustrate how to obtain known results for the special cases of single-layer and multiplex networks. Our tensorial approach will be helpful for tackling pressing problems in multilayer complex systems, such as inferring who is influencing whom (and by which media) in multichannel social networks and developing routing techniques for multimodal transportation systems.

  17. Network Science Based Quantification of Resilience Demonstrated on the Indian Railways Network

    Science.gov (United States)

    Bhatia, Udit; Kumar, Devashish; Kodra, Evan; Ganguly, Auroop R.

    2015-01-01

    The structure, interdependence, and fragility of systems ranging from power-grids and transportation to ecology, climate, biology and even human communities and the Internet have been examined through network science. While response to perturbations has been quantified, recovery strategies for perturbed networks have usually been either discussed conceptually or through anecdotal case studies. Here we develop a network science based quantitative framework for measuring, comparing and interpreting hazard responses as well as recovery strategies. The framework, motivated by the recently proposed temporal resilience paradigm, is demonstrated with the Indian Railways Network. Simulations inspired by the 2004 Indian Ocean Tsunami and the 2012 North Indian blackout as well as a cyber-physical attack scenario illustrate hazard responses and effectiveness of proposed recovery strategies. Multiple metrics are used to generate various recovery strategies, which are simply sequences in which system components should be recovered after a disruption. Quantitative evaluation of these strategies suggests that faster and more efficient recovery is possible through network centrality measures. Optimal recovery strategies may be different per hazard, per community within a network, and for different measures of partial recovery. In addition, topological characterization provides a means for interpreting the comparative performance of proposed recovery strategies. The methods can be directly extended to other Large-Scale Critical Lifeline Infrastructure Networks including transportation, water, energy and communications systems that are threatened by natural or human-induced hazards, including cascading failures. Furthermore, the quantitative framework developed here can generalize across natural, engineered and human systems, offering an actionable and generalizable approach for emergency management in particular as well as for network resilience in general. PMID:26536227

  18. Network Science Based Quantification of Resilience Demonstrated on the Indian Railways Network.

    Science.gov (United States)

    Bhatia, Udit; Kumar, Devashish; Kodra, Evan; Ganguly, Auroop R

    2015-01-01

    The structure, interdependence, and fragility of systems ranging from power-grids and transportation to ecology, climate, biology and even human communities and the Internet have been examined through network science. While response to perturbations has been quantified, recovery strategies for perturbed networks have usually been either discussed conceptually or through anecdotal case studies. Here we develop a network science based quantitative framework for measuring, comparing and interpreting hazard responses as well as recovery strategies. The framework, motivated by the recently proposed temporal resilience paradigm, is demonstrated with the Indian Railways Network. Simulations inspired by the 2004 Indian Ocean Tsunami and the 2012 North Indian blackout as well as a cyber-physical attack scenario illustrate hazard responses and effectiveness of proposed recovery strategies. Multiple metrics are used to generate various recovery strategies, which are simply sequences in which system components should be recovered after a disruption. Quantitative evaluation of these strategies suggests that faster and more efficient recovery is possible through network centrality measures. Optimal recovery strategies may be different per hazard, per community within a network, and for different measures of partial recovery. In addition, topological characterization provides a means for interpreting the comparative performance of proposed recovery strategies. The methods can be directly extended to other Large-Scale Critical Lifeline Infrastructure Networks including transportation, water, energy and communications systems that are threatened by natural or human-induced hazards, including cascading failures. Furthermore, the quantitative framework developed here can generalize across natural, engineered and human systems, offering an actionable and generalizable approach for emergency management in particular as well as for network resilience in general.

  19. Network Science Based Quantification of Resilience Demonstrated on the Indian Railways Network.

    Directory of Open Access Journals (Sweden)

    Udit Bhatia

    Full Text Available The structure, interdependence, and fragility of systems ranging from power-grids and transportation to ecology, climate, biology and even human communities and the Internet have been examined through network science. While response to perturbations has been quantified, recovery strategies for perturbed networks have usually been either discussed conceptually or through anecdotal case studies. Here we develop a network science based quantitative framework for measuring, comparing and interpreting hazard responses as well as recovery strategies. The framework, motivated by the recently proposed temporal resilience paradigm, is demonstrated with the Indian Railways Network. Simulations inspired by the 2004 Indian Ocean Tsunami and the 2012 North Indian blackout as well as a cyber-physical attack scenario illustrate hazard responses and effectiveness of proposed recovery strategies. Multiple metrics are used to generate various recovery strategies, which are simply sequences in which system components should be recovered after a disruption. Quantitative evaluation of these strategies suggests that faster and more efficient recovery is possible through network centrality measures. Optimal recovery strategies may be different per hazard, per community within a network, and for different measures of partial recovery. In addition, topological characterization provides a means for interpreting the comparative performance of proposed recovery strategies. The methods can be directly extended to other Large-Scale Critical Lifeline Infrastructure Networks including transportation, water, energy and communications systems that are threatened by natural or human-induced hazards, including cascading failures. Furthermore, the quantitative framework developed here can generalize across natural, engineered and human systems, offering an actionable and generalizable approach for emergency management in particular as well as for network resilience in general.

  20. Strategic assessment of capacity consumption in railway networks: Framework and model

    DEFF Research Database (Denmark)

    Jensen, Lars Wittrup; Landex, Alex; Nielsen, Otto Anker

    2017-01-01

    In this paper, we develop a new framework for strategic planning purposes to calculate railway infrastructure occupation and capacity consumption in networks, independent of a timetable. Furthermore, a model implementing the framework is presented. In this model different train sequences...... are obtained efficiently with little input. The case illustrates the model's ability to quantify the capacity gain from infrastructure scenario to infrastructure scenario which can be used to increase the number of trains or improve the robustness of the system....

  1. A Bi-Level Programming Model for the Railway Express Cargo Service Network Design Problem

    Directory of Open Access Journals (Sweden)

    Boliang Lin

    2018-06-01

    Full Text Available Service network design is fundamentally crucial for railway express cargo transportation. The main challenge is to strike a balance between two conflicting objectives: low network setup costs and high expected operational incomes. Different configurations of these objectives will have different impacts on the quality of freight transportation services. In this paper, a bi-level programming model for the railway express cargo service network design problem is proposed. The upper-level model forms the optimal decisions in terms of the service characteristics, and the low-level model selects the service arcs for each commodity. The rail express cargo is strictly subject to the service commitment, the capacity restriction, flow balance constraints, and logical relationship constraints among the decisions variables. Moreover, linearization techniques are used to convert the lower-level model to a linear one so that it can be directly solved by a standard optimization solver. Finally, a real-world case study based on the Beijing–Guangzhou Railway Line is carried out to demonstrate the effectiveness and efficiency of the proposed solution approach.

  2. ON OPERATION OF 740 M LONG FREIGHT TRAINS ON CZECH TEN-T RAILWAY NETWORK

    Directory of Open Access Journals (Sweden)

    Michal Drábek

    2016-09-01

    Full Text Available Regulation (EU No 1315/2013 defines actual scope of core and comprehensive TEN-T network, including both networks for railway freight transport. For the core network, possibility to operate 740 m long freight trains is required. The aim of this paper is to analyse availability of appropriate overtaking tracks for 740 m long freight trains. Due to ETCS braking curves and odometry, such trains, after ETCS implementation, will require 780-800 m long overtaking tracks. For practical reasons (e.g. bypass lines, whole Czech railway TEN-T network is analysed. The overtaking track, whose occupation means influence on scheduled traffic or threat to boarding passengers, are excluded. The data was collected from station schemes from Collection of Official Requisites for 2015/16 Timetable, issued by SŽDC, Czech state Infrastructure Manager. Most of appropriate tracks are over 800 m long, but their density in the network and in particular directions varies considerably. For freight traffic, gradient of the line is important, so in the resulting figure, there are marked significant peaks for particular lines as well. Czech TEN-T lines are further segmented on the basis of number of tracks and their traffic character. Then, specific issues on overtaking or crossing of 740 m long freight trains are discussed. As a conclusion, for long-term development of Czech TEN-T lines, targeted investment is recommended not only for passenger railway, but also for freight railway. An attractive capacity offer for railway undertakings, which can stimulate freight traffic on European Rail freight corridors, can be represented by network-bound periodic freight train paths with suitable long overtaking tracks outside bottlenecks. After the overtaking by passenger trains, a freight train should run without stop through large node station or a bottleneck area. Before the sections with high gradients, coupling of additional locomotives should be connected with the overtaking

  3. Capacity factors of a mixed speed railway network

    DEFF Research Database (Denmark)

    Harrod, Steven

    2009-01-01

    Fifty-four combinations of track network and speed differential are evaluated within a linear, discrete time network model that maximizes an objective function of train volume, delays, and idle train time. The results contradict accepted dispatching practice by suggesting that when introducing...... a priority, high-speed train onto a network, maximum network now is attained when the priority train operates at maximum speed. in addition, increasing siding capacity at meeting points may offer a network capacity improvement comparable to partial double track. (C) 2009 Elsevier Ltd. All rights reserved....

  4. Mathematical Modelling Plant Signalling Networks

    KAUST Repository

    Muraro, D.

    2013-01-01

    During the last two decades, molecular genetic studies and the completion of the sequencing of the Arabidopsis thaliana genome have increased knowledge of hormonal regulation in plants. These signal transduction pathways act in concert through gene regulatory and signalling networks whose main components have begun to be elucidated. Our understanding of the resulting cellular processes is hindered by the complex, and sometimes counter-intuitive, dynamics of the networks, which may be interconnected through feedback controls and cross-regulation. Mathematical modelling provides a valuable tool to investigate such dynamics and to perform in silico experiments that may not be easily carried out in a laboratory. In this article, we firstly review general methods for modelling gene and signalling networks and their application in plants. We then describe specific models of hormonal perception and cross-talk in plants. This mathematical analysis of sub-cellular molecular mechanisms paves the way for more comprehensive modelling studies of hormonal transport and signalling in a multi-scale setting. © EDP Sciences, 2013.

  5. Mathematical Properties of Complex Networks

    Directory of Open Access Journals (Sweden)

    Angel Garrido

    2011-01-01

    Full Text Available Many researchers are attempting to create systems which
    mimic human thought, or understand speech, or beat to the best human chess-player [14]. Understanding intelligence and Creating intelligent artifacts both are the twin goals of Artificial Intelligence (AI.In more recent times, the interest is focused on problems related with Complex Networks [3, 5,6, 19], in particular on questions such as clustering search and identification. We attempt, in this paper, a panoramic vision of such mathematical methods in AI.

  6. Two-Layer Hierarchy Optimization Model for Communication Protocol in Railway Wireless Monitoring Networks

    Directory of Open Access Journals (Sweden)

    Xiaoping Ma

    2018-01-01

    Full Text Available The wireless monitoring system is always destroyed by the insufficient energy of the sensors in railway. Hence, how to optimize the communication protocol and extend the system lifetime is crucial to ensure the stability of system. However, the existing studies focused primarily on cluster-based or multihop protocols individually, which are ineffective in coping with the complex communication scenarios in the railway wireless monitoring system (RWMS. This study proposes a hybrid protocol which combines the cluster-based and multihop protocols (CMCP to minimize and balance the energy consumption in different sections of the RWMS. In the first hierarchy, the total energy consumption is minimized by optimizing the cluster quantities in the cluster-based protocol and the number of hops and the corresponding hop distances in the multihop protocol. In the second hierarchy, the energy consumption is balanced through rotating the cluster head (CH in the subnetworks and further optimizing the hops and the corresponding hop distances in the backbone network. On this basis, the system lifetime is maximized with the minimum and balance energy consumption among the sensors. Furthermore, the hybrid particle swarm optimization and genetic algorithm (PSO-GA are adopted to optimize the energy consumption from the two-layer hierarchy. Finally, the effectiveness of the proposed CMCP is verified in the simulation. The performances of the proposed CMCP in system lifetime, residual energy, and the corresponding variance are all superior to the LEACH protocol widely applied in the previous research. The effective protocol proposed in this study can facilitate the application of the wireless monitoring network in the railway system and enhance safety operation of the railway.

  7. Mathematical theories of distributed sensor networks

    CERN Document Server

    Iyengar, Sitharama S; Balakrishnan, N

    2014-01-01

    Mathematical Theory of Distributed Sensor Networks demonstrates how mathematical theories can be used to provide distributed sensor modeling and to solve important problems such as coverage hole detection and repair. The book introduces the mathematical and computational structure by discussing what they are, their applications and how they differ from traditional systems. The text also explains how mathematics are utilized to provide efficient techniques implementing effective coverage, deployment, transmission, data processing, signal processing, and data protection within distributed sensor networks. Finally, the authors discuss some important challenges facing mathematics to get more incite to the multidisciplinary area of distributed sensor networks.

  8. An optimisation framework for determination of capacity in railway networks

    DEFF Research Database (Denmark)

    Jensen, Lars Wittrup

    2015-01-01

    network based on a mix of train types, the infrastructure and rolling stock used. The framework consist of two steps. In the first step the maximum number of trains is found according to the predefined mix of train types. In the second step additional trains are added based on weights assigned...

  9. Electromagnetic interference produced by power or electrified railway lines on metallic pipe networks

    International Nuclear Information System (INIS)

    Lucca, G.

    1999-01-01

    The paper presents an algorithm for the calculation, in the frequency domain, of the induced voltages and currents on a generic metallic pipe network exposed to the electromagnetic interference from a power line or an electrified railway line. By assuming as known the voltages and the currents on the inducing line, the algorithm may be subdivided into the following main steps: a) determination of the ideal electromotive force and current generators to be applied to the induced structure in order to represent the electromagnetic influence from the inducing line; b) modelling of the pipe network by means of a suitable equivalent electric network; c) calculation of voltages and currents on the induced network [it

  10. Computation and evaluation of scheduled waiting time for railway networks

    DEFF Research Database (Denmark)

    Landex, Alex

    2010-01-01

    Timetables are affected by scheduled waiting time (SWT) that prolongs the travel times for trains and thereby passengers. SWT occurs when a train hinders another train to run with the wanted speed. The SWT affects both the trains and the passengers in the trains. The passengers may be further...... affected due to longer transfer times to other trains. SWT can be estimated analytically for a given timetable or by simulation of timetables and/or plans of operation. The simulation of SWT has the benefit that it is possible to examine the entire network. This makes it possible to improve the future...

  11. Train-Network Interactions and Stability Evaluation in High-Speed Railways--Part II: Influential Factors and Verifications

    DEFF Research Database (Denmark)

    Hu, Haitao; Tao, Haidong; Wang, Xiongfei

    2018-01-01

    Low-frequency oscillation (LFO), harmonic resonance and resonance instability phenomena happened in high speed railways (HSRs) are resulted from the interactions between multiple electric trains and traction network. A train-network interaction system and a unified impedance-based model......, catenary lines and autotransformers (ATs); 3) different numbers and positions of trains and railway lines will also be considered and discussed. In order to validate the theoretical results, the time-domain simulation and experiment system have been conducted. Finally, the differences and the relations...

  12. Railway optimal network simulation for the development of regional transport-logistics system

    Directory of Open Access Journals (Sweden)

    Mikhail Borisovich Petrov

    2013-12-01

    Full Text Available The dependence of logistics on mineral fuel is a stable tendency of regions development, though when making strategic plans of logistics in the regions, it is necessary to provide the alternative possibilities of power-supply sources change together with population density, transport infrastructure peculiarities, and demographic changes forecast. On the example of timber processing complex of the Sverdlovsk region, the authors suggest the algorithm of decision of the optimal logistics infrastructure allocation. The problem of regional railway network organization at the stage of slow transition from the prolonged stagnation to the new development is carried out. The transport networks’ configurations of countries on the Pacific Rim, which successfully developed nowadays, are analyzed. The authors offer some results of regional transport network simulation on the basis of artificial intelligence method. These methods let to solve the task with incomplete data. The ways of the transport network improvement in the Sverdlovsk region are offered.

  13. Automatic Railway Traffic Object Detection System Using Feature Fusion Refine Neural Network under Shunting Mode

    Directory of Open Access Journals (Sweden)

    Tao Ye

    2018-06-01

    Full Text Available Many accidents happen under shunting mode when the speed of a train is below 45 km/h. In this mode, train attendants observe the railway condition ahead using the traditional manual method and tell the observation results to the driver in order to avoid danger. To address this problem, an automatic object detection system based on convolutional neural network (CNN is proposed to detect objects ahead in shunting mode, which is called Feature Fusion Refine neural network (FR-Net. It consists of three connected modules, i.e., the depthwise-pointwise convolution, the coarse detection module, and the object detection module. Depth-wise-pointwise convolutions are used to improve the detection in real time. The coarse detection module coarsely refine the locations and sizes of prior anchors to provide better initialization for the subsequent module and also reduces search space for the classification, whereas the object detection module aims to regress accurate object locations and predict the class labels for the prior anchors. The experimental results on the railway traffic dataset show that FR-Net achieves 0.8953 mAP with 72.3 FPS performance on a machine with a GeForce GTX1080Ti with the input size of 320 × 320 pixels. The results imply that FR-Net takes a good tradeoff both on effectiveness and real time performance. The proposed method can meet the needs of practical application in shunting mode.

  14. High-speed railway real-time localization auxiliary method based on deep neural network

    Science.gov (United States)

    Chen, Dongjie; Zhang, Wensheng; Yang, Yang

    2017-11-01

    High-speed railway intelligent monitoring and management system is composed of schedule integration, geographic information, location services, and data mining technology for integration of time and space data. Assistant localization is a significant submodule of the intelligent monitoring system. In practical application, the general access is to capture the image sequences of the components by using a high-definition camera, digital image processing technique and target detection, tracking and even behavior analysis method. In this paper, we present an end-to-end character recognition method based on a deep CNN network called YOLO-toc for high-speed railway pillar plate number. Different from other deep CNNs, YOLO-toc is an end-to-end multi-target detection framework, furthermore, it exhibits a state-of-art performance on real-time detection with a nearly 50fps achieved on GPU (GTX960). Finally, we realize a real-time but high-accuracy pillar plate number recognition system and integrate natural scene OCR into a dedicated classification YOLO-toc model.

  15. Fault Detection for Large-Scale Railway Maintenance Equipment Base on Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Junfu Yu

    2014-04-01

    Full Text Available Focusing on the fault detection application for large-scale railway maintenance equipment with the specialties of low-cost, energy efficiency, collecting data of the function units. This paper proposed energy efficiency, convenient installation fault detection application using Sigsbee wireless sensor networks, which Sigsbee is the most widely used protocol based on IEEE 802.15.4. This paper proposed a systematic application from hardware design using STM32F103 chips as processer, to software system. Fault detection application is the basic part of the fault diagnose system, wireless sensor nodes of the fault detection application with different kinds of sensors for verities function units communication by Sigsbee to collecting and sending basic working status data to the home gateway, then data will be sent to the fault diagnose system.

  16. An assessment of available measures to reduce traction energy use in railway networks

    International Nuclear Information System (INIS)

    Douglas, Heather; Roberts, Clive; Hillmansen, Stuart; Schmid, Felix

    2015-01-01

    Highlights: • Railway networks are defined in terms of their distinguishing features. • Current energy saving measures are reviewed and categorised by the energy use they target. • The achievable energy savings of different measures are compared dependent on the network type. • The success of a measure depends on the characteristics of the network, vehicle and service. • Measures should be evaluated at system level due to interdependencies. - Abstract: Rail is becoming an increasingly popular choice to satisfy transportation demands locally, nationally and internationally, due to its inherent efficiency and high capacity. Despite this, operators are facing pressure to reduce rail energy consumption to meet efficiency targets, whilst still maintaining service quality and managing increased demand. A number of individual measures have been proposed to reduce energy in the rail sector, often showing good results on specific case studies. It is generally agreed that the attainable savings of a given measure change dependant on the route, vehicle and service characteristics. However, there is little information in the literature specifically regarding which measures are most suitable for given network types, or how they interact. This paper therefore aims to begin evaluating the available measures in terms of their suitability for different systems. Firstly, networks are defined in terms of their distinguishing features. As traction accounts for the majority of all energy use in the rail sector, the traction flow through a vehicle is considered as the starting point for an evaluation of measures. Current technologies and procedures are reviewed and categorised based on which area of traction use they target. Thought is given to the factors that affect implementation and the networks where they are applied. A key output of this paper is a comparison of the achievable energy savings of different measures dependent on the network type. It is hoped that this will

  17. A Bayesian Network methodology for railway risk, safety and decision support

    OpenAIRE

    Mahboob, Qamar

    2014-01-01

    For railways, risk analysis is carried out to identify hazardous situations and their consequences. Until recently, classical methods such as Fault Tree Analysis (FTA) and Event Tree Analysis (ETA) were applied in modelling the linear and logically deterministic aspects of railway risks, safety and reliability. However, it has been proven that modern railway systems are rather complex, involving multi-dependencies between system variables and uncertainties about these dependencies. For train ...

  18. A Control Simulation Method of High-Speed Trains on Railway Network with Irregular Influence

    International Nuclear Information System (INIS)

    Yang Lixing; Li Xiang; Li Keping

    2011-01-01

    Based on the discrete time method, an effective movement control model is designed for a group of highspeed trains on a rail network. The purpose of the model is to investigate the specific traffic characteristics of high-speed trains under the interruption of stochastic irregular events. In the model, the high-speed rail traffic system is supposed to be equipped with the moving-block signalling system to guarantee maximum traversing capacity of the railway. To keep the safety of trains' movements, some operational strategies are proposed to control the movements of trains in the model, including traction operation, braking operation, and entering-station operation. The numerical simulations show that the designed model can well describe the movements of high-speed trains on the rail network. The research results can provide the useful information not only for investigating the propagation features of relevant delays under the irregular disturbance but also for rerouting and rescheduling trains on the rail network. (general)

  19. ECONOMIC AND MATHEMATICAL MODEL OF PREDICTION OF DEVIATION IN MOSCOW SUBURBAN RAILWAY COMPLEX

    Directory of Open Access Journals (Sweden)

    Dmitry I. Valdman

    2013-01-01

    Full Text Available The article deals with the theoretical aspects of mathematical modeling and forecasting. Additionally, it describes a mathematical model for forecasting the number of incidents, depending on the number of different types of planned works with one and the same subject in service facilities, validation of the model via substituting of the data and comparing the predicted values calculated by the model and the actual values for the same periods.

  20. Prediction Study on Anti-Slide Control of Railway Vehicle Based on RBF Neural Networks

    Science.gov (United States)

    Yang, Lijun; Zhang, Jimin

    While railway vehicle braking, Anti-slide control system will detect operating status of each wheel-sets e.g. speed difference and deceleration etc. Once the detected value on some wheel-set is over pre-defined threshold, brake effort on such wheel-set will be adjusted automatically to avoid blocking. Such method takes effect on guarantee safety operation of vehicle and avoid wheel-set flatness, however it cannot adapt itself to the rail adhesion variation. While wheel-sets slide, the operating status is chaotic time series with certain law, and can be predicted with the law and experiment data in certain time. The predicted values can be used as the input reference signals of vehicle anti-slide control system, to judge and control the slide status of wheel-sets. In this article, the RBF neural networks is taken to predict wheel-set slide status in multi-step with weight vector adjusted based on online self-adaptive algorithm, and the center & normalizing parameters of active function of the hidden unit of RBF neural networks' hidden layer computed with K-means clustering algorithm. With multi-step prediction simulation, the predicted signal with appropriate precision can be used by anti-slide system to trace actively and adjust wheel-set slide tendency, so as to adapt to wheel-rail adhesion variation and reduce the risk of wheel-set blocking.

  1. A Wireless Sensor Network with Enhanced Power Efficiency and Embedded Strain Cycle Identification for Fatigue Monitoring of Railway Bridges

    OpenAIRE

    Feltrin, Glauco; Popovic, Nemanja; Flouri, Kallirroi; Pietrzak, Piotr

    2016-01-01

    Wireless sensor networks have been shown to be a cost-effective monitoring tool for many applications on civil structures. Strain cycle monitoring for fatigue life assessment of railway bridges, however, is still a challenge since it is data intensive and requires a reliable operation for several weeks or months. In addition, sensing with electrical resistance strain gauges is expensive in terms of energy consumption. The induced reduction of battery lifetime of sensor nodes increases the mai...

  2. Mathematical model of highways network optimization

    Science.gov (United States)

    Sakhapov, R. L.; Nikolaeva, R. V.; Gatiyatullin, M. H.; Makhmutov, M. M.

    2017-12-01

    The article deals with the issue of highways network design. Studies show that the main requirement from road transport for the road network is to ensure the realization of all the transport links served by it, with the least possible cost. The goal of optimizing the network of highways is to increase the efficiency of transport. It is necessary to take into account a large number of factors that make it difficult to quantify and qualify their impact on the road network. In this paper, we propose building an optimal variant for locating the road network on the basis of a mathematical model. The article defines the criteria for optimality and objective functions that reflect the requirements for the road network. The most fully satisfying condition for optimality is the minimization of road and transport costs. We adopted this indicator as a criterion of optimality in the economic-mathematical model of a network of highways. Studies have shown that each offset point in the optimal binding road network is associated with all other corresponding points in the directions providing the least financial costs necessary to move passengers and cargo from this point to the other corresponding points. The article presents general principles for constructing an optimal network of roads.

  3. Railway networks 2025/2030. Expansion concept for an efficient rail cargo traffic in Germany; Schienennetz 2025/2030. Ausbaukonzeption fuer einen leistungsfaehigen Schienengueterverkehr in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Holzhey, Michael [KCW GmbH, Berlin (Germany)

    2010-08-15

    This study investigated the need for the construction of new railway lines and expansion of the existing railway network in Germany. The target to be achieved was based on the UBA strategy of being able to absorb 213 billion tkm on the rail by 2025. The time factor is not really that important, however; what counts is the selection of a target that forces all parties concerned to make infrastructural plans and think ahead if they are convinced in principle of the advantages of railway cargo transport. (orig.)

  4. Selected Problems of Determining the Course of Railway Routes by Use of GPS Network Solution

    Science.gov (United States)

    Koc, Władysław; Specht, Cezary

    2011-09-01

    The main problem related to railroad surveying design and its maintenance is the necessity to operate in local geodetic reference systems caused by the long rail sections with straight lines and curvatures of the running edge. Due to that reason the geodetic railroad classical surveying methods requires to divide all track for a short measurement section and that caused additional errors. Development of the Global Navigational Satellite Systems (GNSS) positioning methods operating in the standardized World Geodetic System (WGS-84) allowed verification of capability of utilization GPS measurements for railroad surveying. It can be stated that implemented satellite measurement techniques opens a whole new perspective on applied research and enables very precise determination of data for railway line determining, modernization and design. The research works focused on implementation GNSS multi-receivers measurement positioning platform for projecting and stock-taking working based on polish active geodesic network ASG-EUPOS, as a reference frame. In order to eliminate the influence of random measurement errors and to obtain the coordinates representing the actual shape of the track few campaigns were realized in 2009 and 2010. Leica GPS Total station system 1200 SmartRover (with ATX1230 GG antennas) receivers were located in the diameter of the measurement platform. Polish Active Geodetic Network ASG-EUPOS was used as a reference network transmitted Real Time Kinematic Positioning Service according to RTCM 3.1 standard. Optimum time period were selected for GNSS campaign and testing area was chosen without large obstructions. The article presents some surveying results of the measurement campaigns and also discusses the accuracy of the course determination. Analyzes and implementation of results in railroad design process are also discussed.

  5. Energy Efficiency and Capacity Tradeoff in Cloud Radio Access Network of High-Speed Railways

    Directory of Open Access Journals (Sweden)

    Shichao Li

    2017-01-01

    Full Text Available To meet the increasing demand of high-data-rate services of high-speed railway (HSR passengers, cloud radio access network (C-RAN is proposed. This paper investigates the tradeoff between energy efficiency (EE performance and capacity in C-RAN of HSR. Considering that the train location can be predicted, we propose a predictable path loss based time domain power allocation method (PPTPA to improve EE performance of HSR communication system. First, we consider that the communication system of HSR only bears the passenger information services (PISs. The energy-efficient power allocation problem with delay constraint is studied. The formulated problem is nonconvex. To deal with it, an equivalent convex problem is reformulated. Based on PPTPA, we propose an iterative algorithm to improve the EE performance. Second, we consider that the PISs and the train control services (TCSs are all bore. A capacity optimization problem with joint EE and services transmission delay constraints is formulated. Based on PPTPA, we propose a hybrid power allocation scheme to improve the capacity of the system. Finally, we analyze the effect of small-scale fading on EE performance. The effectiveness of the proposed power allocation algorithm is validated by HSR channel measurement trace based emulation results and extensive simulation results.

  6. Planning Optimization of the Distributed Antenna System in High-Speed Railway Communication Network Based on Improved Cuckoo Search

    Directory of Open Access Journals (Sweden)

    Zhaoyu Chen

    2018-01-01

    Full Text Available The network planning is a key factor that directly affects the performance of the wireless networks. Distributed antenna system (DAS is an effective strategy for the network planning. This paper investigates the antenna deployment in a DAS for the high-speed railway communication networks and formulates an optimization problem which is NP-hard for achieving the optimal deployment of the antennas in the DAS. To solve this problem, a scheme based on an improved cuckoo search based on dimension cells (ICSDC algorithm is proposed. ICSDC introduces the dimension cell mechanism to avoid the internal dimension interferences in order to improve the performance of the algorithm. Simulation results show that the proposed ICSDC-based scheme obtains a lower network cost compared with the uniform network planning method. Moreover, ICSDC algorithm has better performance in terms of the convergence rate and accuracy compared with the conventional cuckoo search algorithm, the particle swarm optimization, and the firefly algorithm.

  7. Capacity at Railway Stations

    DEFF Research Database (Denmark)

    Landex, Alex

    2011-01-01

    zone(s) the possible conflicts with other trains (also in the opposite direction) are taken into account leading to more trustworthy results. Although the UIC 406 methodology proposes that the railway network should be divided into line sections when trains turn around and when the train order...... is changed, this paper recommends that the railway lines are not always be divided. In case trains turn around on open (single track) line, the capacity consumption may be too low if a railway line is divided. The same can be the case if only few trains are overtaken at an overtaking station. For dead end...

  8. VoLTE performance in railway scenarios

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Sønderskov, Morten; Soler, José

    2015-01-01

    GSM-Railways (GSM-R) is the current standard for railway voice and data communication. GSM-R provides railway specific voice services, such as Railway Emergency Call (REC). GSM-R provides also the European Train Control System (ETCS), which offers in-cab signaling and Automatic Train Protection...... (ATP). Despite these features and services, GSM-R has various major shortcomings. Therefore, alternative technologies are considered to replace GSM-R and become the next generation railway mobile communication network. 3GPP Long Term Evolution (LTE) is a likely candidate for GSM-R replacement. LTE...... is more efficient, flexible and offers much higher capacity, which allows the railway network to provide new communication-based applications for railways. Most of the research on LTE in railways has been focused on data-based railway applications (ETCS signaling and other). Nevertheless, voice...

  9. VoLTE Performance in Railway Scenarios

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Sønderskov, Morten; Soler, José

    2015-01-01

    GSM-Railways (GSM-R) is the current standard for railway voice and data communication. GSM-R provides railway specific voice services, such as Railway Emergency Call (REC). GSM-R provides also the European Train Control System (ETCS), which offers in-cab signaling and Automatic Train Protection...... (ATP). Despite these features and services, GSM-R has various major shortcomings. Therefore, alternative technologies are considered to replace GSM-R and become the next generation railway mobile communication network. 3GPP Long Term Evolution (LTE) is a likely candidate for GSM-R replacement. LTE...... is more efficient, flexible and offers much higher capacity, which allows the railway network to provide new communication-based applications for railways. Most of the research on LTE in railways has been focused on data-based railway applications (ETCS signaling and other). Nevertheless, voice...

  10. Towards a whole-network risk assessment for railway bridge failures caused by scour during flood events

    Directory of Open Access Journals (Sweden)

    Lamb Rob

    2016-01-01

    Full Text Available Localised erosion (scour during flood flow conditions can lead to costly damage or catastrophic failure of bridges, and in some cases loss of life or significant disruption to transport networks. Here, we take a broad scale view to assess risk associated with bridge scour during flood events over an entire infrastructure network, illustrating the analysis with data from the British railways. There have been 54 recorded events since 1846 in which scour led to the failure of railway bridges in Britain. These events tended to occur during periods of extremely high river flow, although there is uncertainty about the precise conditions under which failures occur, which motivates a probabilistic analysis of the failure events. We show how data from the historical bridge failures, combined with hydrological analysis, have been used to construct fragility curves that quantify the conditional probability of bridge failure as a function of river flow, accompanied by estimates of the associated uncertainty. The new fragility analysis is tested using flood events simulated from a national, spatial joint probability model for extremes in river flows. The combined models appear robust in comparison with historical observations of the expected number of bridge failures in a flood event, and provide an empirical basis for further broad-scale network risk analysis.

  11. Study on the correlation between the hierarchical urban system and high-speed railway network planning in China

    Directory of Open Access Journals (Sweden)

    Hong Sun

    2016-09-01

    Full Text Available This study examines the interrelatedness between the hierarchical structure of China׳s urban system and high-speed railway (HSR network planning at the national level. As a multi-layered system, the Chinese HSR can be categorized into three sub-networks, namely, the national HSR trunk network, the national HSR extensional network, and the intercity HSR network. By examining the direct HSR network connection, HSR nodal connection, and HSR operational frequency of 287 prefecture-level cities, this study demonstrates that the hierarchies of China׳s administrative, demographic, and economic urban systems strongly influence HSR network planning. The national HSR trunk network prioritizes the connection of top-level central cities, whereas the extensional network prioritizes cities at the lower level of the urban system. Moreover, the national HSR system forms the backbone of the HSR network structure based on a national scale, whereas the intercity HSR system satisfies the travel needs within urban agglomerations based on the regional level.

  12. Conference on "Mathematical Technology of Networks"

    CERN Document Server

    2015-01-01

    Bringing together leading researchers in the fields of functional analysis, mathematical physics and graph theory, as well as natural scientists using networks as a tool in their own research fields, such as neuroscience and machine learning, this volume presents recent advances in functional, analytical, probabilistic, and spectral aspects in the study of graphs, quantum graphs, and complex networks. The contributors to this volume explore the interplay between theoretical and applied aspects of discrete and continuous graphs. Their work helps to close the gap between different avenues of research on graphs, including metric graphs and ramified structures. All papers were presented at the conference "Mathematical Technology of Networks," held December 4–7, 2013 at the Zentrum für interdisziplinäre Forschung (ZiF) in Bielefeld, Germany, and are supplemented with detailed figures illustrating both abstract concepts as well as their real-world applications. Dynamical models on graphs or random graphs a...

  13. Towards a real-time Structural Health Monitoring of railway bridges

    OpenAIRE

    Vagnoli, Matteo; Remenyte-Prescott, Rasa; Andrews, John

    2017-01-01

    More than 350,000 railway bridges are present on the European railway network, making them a key infrastructure of the whole railway network. Railway bridges are continuously exposed to changing environmental threats, such as wind, floods and traffic load, which can affect safety and reliability of the bridge. Furthermore, a problem on a bridge can affect the whole railway network by increasing the vulnerability of the geographic area, served by the railway network. In this paper a Bayesian B...

  14. A Wireless Sensor Network with Enhanced Power Efficiency and Embedded Strain Cycle Identification for Fatigue Monitoring of Railway Bridges

    Directory of Open Access Journals (Sweden)

    Glauco Feltrin

    2016-01-01

    Full Text Available Wireless sensor networks have been shown to be a cost-effective monitoring tool for many applications on civil structures. Strain cycle monitoring for fatigue life assessment of railway bridges, however, is still a challenge since it is data intensive and requires a reliable operation for several weeks or months. In addition, sensing with electrical resistance strain gauges is expensive in terms of energy consumption. The induced reduction of battery lifetime of sensor nodes increases the maintenance costs and reduces the competitiveness of wireless sensor networks. To overcome this drawback, a signal conditioning hardware was designed that is able to significantly reduce the energy consumption. Furthermore, the communication overhead is reduced to a sustainable level by using an embedded data processing algorithm that extracts the strain cycles from the raw data. Finally, a simple software triggering mechanism that identifies events enabled the discrimination of useful measurements from idle data, thus increasing the efficiency of data processing. The wireless monitoring system was tested on a railway bridge for two weeks. The monitoring system demonstrated a good reliability and provided high quality data.

  15. Mathematical and theoretical neuroscience cell, network and data analysis

    CERN Document Server

    Nieus, Thierry

    2017-01-01

    This volume gathers contributions from theoretical, experimental and computational researchers who are working on various topics in theoretical/computational/mathematical neuroscience. The focus is on mathematical modeling, analytical and numerical topics, and statistical analysis in neuroscience with applications. The following subjects are considered: mathematical modelling in Neuroscience, analytical  and numerical topics;  statistical analysis in Neuroscience; Neural Networks; Theoretical Neuroscience. The book is addressed to researchers involved in mathematical models applied to neuroscience.

  16. Feasibility study for linking railway network and power transmission infrastructure; Machbarkeitsstudie zur Verknuepfung von Bahn- und Energieleitungsinfrastrukturen

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Lutz; Rathke, Christian [Hannover Univ. (Germany). Inst. fuer Energieversorgung und Hochspannungstechnik; Stephan, Arnd; Albrecht, Andreas [Technische Univ. Dresden (Germany). Inst. fuer Bahnfahrzeuge und Bahntechnik; Weyer, Hartmut; Lismann, Christian (comps.) [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Deutsches und Internationales Berg- und Energierecht

    2013-03-15

    At times of growing emergencies of electricity transport, the extension of transmission becomes a necessary and compulsory component of the energy concept of the Federal Government. The extension of the capacities of the network transportation from North to South and from east to West is inevitable. Under this aspect, the contribution under consideration analyzes whether and to what extent the utilization of the existing railways potentials of the 16.7 Hz traction power supply system of the DB Energie GmbH (Frankfurt (Main), Federal Republic of Germany) is possible for the establishment of new power transmission lines of the general 50 Hz power supply. Furthermore, it is investigated to what extent possibilities of infrastructure connections exist in the shape of combined transmission routes between traction supply and public energy supply.

  17. THE RAILMAPPER – A DEDICATED MOBILE LIDAR MAPPING SYSTEM FOR RAILWAY NETWORKS

    Directory of Open Access Journals (Sweden)

    J. Kremer

    2012-07-01

    Full Text Available The Mobile LiDAR Mapping System StreetMapper from IGI and 3D Laser Mapping (Bingham Nottingham, UK is mounted on a large variety of road vehicles to cover different mission specifications. In addition to the operation on the road, the system finds its applications on other kinds of vehicles, like boats or trains. The modular and flexible system concept even allows utilizing the same LiDAR Mapping system for Mobile Mapping on the ground and for airborne missions on helicopters, respectively. Besides this general flexibility, each application has its own special requirements. Special hardware and software components are needed to complete the core components, like the laser scanner and the GNSS/IMU systems, to build a dedicated system for the chosen task. Compared to the typical dynamics of a road vehicle mounted Mobile Mapping system, a dedicated rail mapping system operates under conditions that are much more challenging for a high accuracy GNSS/IMU trajectory determination. Furthermore, the typical rail mapping tasks, like the exact measurement of the rail track geometry, require the operation of the most accurate laser scanners and of specialized post-processing software. In this paper, the RailMapper, a specialized Mobile Mapping system for railway surveys is presented. The system is described with focus on the railway specific requirements and results of practical surveys are given.

  18. The incentive regulation in the network management. A cross-sectorial investigation of the network managements energy, telecommunication and railway; Die Anreizregulierung in den Netzwirtschaften. Eine sektoruebergreifende Untersuchung der Netzwirtschaften Energie, Telekommunikation und Eisenbahn

    Energy Technology Data Exchange (ETDEWEB)

    Berndt, Andrea

    2011-07-01

    The author of the book under consideration reports on a cross-sectoral analysis of network management of energy, telecommunications and railways with regard to incentive regulation. The cross-sectoral analysis of incentive regulation requires a systematization of the instrument of payment regulation. Using the example of the incentive regulation, the author provides a rather jurisprudential contribution to a network management dogma.

  19. Parameters of passenger facilities according to railway station characteristics

    Directory of Open Access Journals (Sweden)

    Ondřej HAVLENA

    2014-12-01

    Full Text Available The article presents ways and goals of categorization of railway stations and stops in the Czech railway network. The aim of this categorization is to classify railway stations (or stops in the railway network according to a suite of entrance parameters (e.g. municipality population, transfer links, job opportunities, tourist attractiveness. On the basis of these parameters, railway stations and stops will be classified into several categories, which will be used to specify the conclusions for station equipment concerning ticket offices, commercial services, waiting rooms and other accessories. Research results can be used as a support for infrastructure managers and railway operators to optimise the scale of their services.

  20. Summer School Mathematical Foundations of Complex Networked Information Systems

    CERN Document Server

    Fosson, Sophie; Ravazzi, Chiara

    2015-01-01

    Introducing the reader to the mathematics beyond complex networked systems, these lecture notes investigate graph theory, graphical models, and methods from statistical physics. Complex networked systems play a fundamental role in our society, both in everyday life and in scientific research, with applications ranging from physics and biology to economics and finance. The book is self-contained, and requires only an undergraduate mathematical background.

  1. Mathematical model for spreading dynamics of social network worms

    International Nuclear Information System (INIS)

    Sun, Xin; Liu, Yan-Heng; Han, Jia-Wei; Liu, Xue-Jie; Li, Bin; Li, Jin

    2012-01-01

    In this paper, a mathematical model for social network worm spreading is presented from the viewpoint of social engineering. This model consists of two submodels. Firstly, a human behavior model based on game theory is suggested for modeling and predicting the expected behaviors of a network user encountering malicious messages. The game situation models the actions of a user under the condition that the system may be infected at the time of opening a malicious message. Secondly, a social network accessing model is proposed to characterize the dynamics of network users, by which the number of online susceptible users can be determined at each time step. Several simulation experiments are carried out on artificial social networks. The results show that (1) the proposed mathematical model can well describe the spreading dynamics of social network worms; (2) weighted network topology greatly affects the spread of worms; (3) worms spread even faster on hybrid social networks

  2. THE ELECTROSTATIC CHARACTERISTICS OF LINEAR INSULATORS FOR CONTACT NETWORKS OF RAILWAYS

    Directory of Open Access Journals (Sweden)

    Ye. D. Kim

    2009-03-01

    Full Text Available On the base of numeric investigations on mathematical models of stationary electric field the basic electric performances of insulating suspensions from porcelain and polymeric insulators for contact nets of alternating and direct current are compared.

  3. Mathematics of epidemics on networks from exact to approximate models

    CERN Document Server

    Kiss, István Z; Simon, Péter L

    2017-01-01

    This textbook provides an exciting new addition to the area of network science featuring a stronger and more methodical link of models to their mathematical origin and explains how these relate to each other with special focus on epidemic spread on networks. The content of the book is at the interface of graph theory, stochastic processes and dynamical systems. The authors set out to make a significant contribution to closing the gap between model development and the supporting mathematics. This is done by: Summarising and presenting the state-of-the-art in modeling epidemics on networks with results and readily usable models signposted throughout the book; Presenting different mathematical approaches to formulate exact and solvable models; Identifying the concrete links between approximate models and their rigorous mathematical representation; Presenting a model hierarchy and clearly highlighting the links between model assumptions and model complexity; Providing a reference source for advanced undergraduate...

  4. Learning mathematics from hierarchies to networks

    CERN Document Server

    Burton, Prof Leone

    2012-01-01

    How and why is mathematics taught? This book seeks to improve on our current answers. The contributors provide various perspectives in this richly cross-referenced work. Relevant to policy makers, practitioners and researchers.

  5. Railway Track Allocation: Models and Methods

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Ehrgott, Matthias

    2011-01-01

    Efficiently coordinating the movement of trains on a railway network is a central part of the planning process for a railway company. This paper reviews models and methods that have been proposed in the literature to assist planners in finding train routes. Since the problem of routing trains......, and train routing problems, group them by railway network type, and discuss track allocation from a strategic, tactical, and operational level....... on a railway network entails allocating the track capacity of the network (or part thereof) over time in a conflict-free manner, all studies that model railway track allocation in some capacity are considered relevant. We hence survey work on the train timetabling, train dispatching, train platforming...

  6. Railway Track Allocation: Models and Methods

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Ehrgott, Matthias

    Eciently coordinating the movement of trains on a railway network is a central part of the planning process for a railway company. This paper reviews models and methods that have been proposed in the literature to assist planners in nding train routes. Since the problem of routing trains......, and train routing problems, group them by railway network type, and discuss track allocation from a strategic, tactical, and operational level....... on a railway network entails allocating the track capacity of the network (or part thereof) over time in a con ict-free manner, all studies that model railway track allocation in some capacity are considered relevant. We hence survey work on the train timetabling, train dispatching, train platforming...

  7. Energy efficient solutions for the complete railway system; Energieeffiziente Loesungen fuer das Gesamtsystem Bahn

    Energy Technology Data Exchange (ETDEWEB)

    Meinert, M.; Rechenberg, K.; Hein, G. [Siemens AG, Erlangen (Germany)

    2007-07-01

    Innovative technologies for the power supply of electric railway vehicles by stationary and mobile devices allow to operate the complete railway system in an energy efficient manner and therefore reduce the energy consumption considerably. So it is necessary to examine the power supply of the railway network as well as the railway vehicles and their own operational behaviour within the railway network. A complete tramway system was choosen as one example. (orig.)

  8. Mathematical Analysis of Urban Spatial Networks

    CERN Document Server

    Blanchard, Philippe

    2009-01-01

    Cities can be considered to be among the largest and most complex artificial networks created by human beings. Due to the numerous and diverse human-driven activities, urban network topology and dynamics can differ quite substantially from that of natural networks and so call for an alternative method of analysis. The intent of the present monograph is to lay down the theoretical foundations for studying the topology of compact urban patterns, using methods from spectral graph theory and statistical physics. These methods are demonstrated as tools to investigate the structure of a number of real cities with widely differing properties: medieval German cities, the webs of city canals in Amsterdam and Venice, and a modern urban structure such as found in Manhattan. Last but not least, the book concludes by providing a brief overview of possible applications that will eventually lead to a useful body of knowledge for architects, urban planners and civil engineers.

  9. Complex networks and SOA: Mathematical modelling of granularity ...

    Indian Academy of Sciences (India)

    We employ statistical and graph-theoretic meth- ... While the interdisciplinary characteristics of network science continues to .... mathematical language and clustering it, even with known methods, can be a daunting task here, let alone ...... Greenacre M J and Balasius J 1994 Correspondence analysis in the social sciences.

  10. Analytic network process (ANP approach for product mix planning in railway industry

    Directory of Open Access Journals (Sweden)

    Hadi Pazoki Toroudi

    2016-08-01

    Full Text Available Given the competitive environment in the global market in recent years, organizations need to plan for increased profitability and optimize their performance. Planning for an appropriate product mix plays essential role for the success of most production units. This paper applies analytical network process (ANP approach for product mix planning for a part supplier in Iran. The proposed method uses four criteria including cost of production, sales figures, supply of raw materials and quality of products. In addition, the study proposes different set of products as alternatives for production planning. The preliminary results have indicated that that the proposed study of this paper could increase productivity, significantly.

  11. Equivalent model and power flow model for electric railway traction network

    Science.gov (United States)

    Wang, Feng

    2018-05-01

    An equivalent model of the Cable Traction Network (CTN) considering the distributed capacitance effect of the cable system is proposed. The model can be divided into 110kV side and 27.5kV side two kinds. The 110kV side equivalent model can be used to calculate the power supply capacity of the CTN. The 27.5kV side equivalent model can be used to solve the voltage of the catenary. Based on the equivalent simplified model of CTN, the power flow model of CTN which involves the reactive power compensation coefficient and the interaction of voltage and current, is derived.

  12. Networking of theories as a research practice in mathematics education

    CERN Document Server

    Bikner-Ahsbahs, Angelika

    2014-01-01

    How can we deal with the diversity of theories in mathematics education This was the main question that led the authors of this book to found the Networking Theories Group. Starting from the shared assumption that the existence of different theories is a resource for mathematics education research, the authors have explored the possibilities of interactions between theories, such as contrasting, coordinating, and locally integrating them. The book explains and illustrates what it means to network theories; it presents networking as a challenging but fruitful research practice and shows how the Group dealt with this challenge considering five theoretical approaches, namely the approach of Action, Production, and Communication (APC), the Theory of Didactical Situations (TDS), the Anthropological Theory of the Didactic (ATD), the approach of Abstraction in Context (AiC), and the Theory of Interest-Dense Situations (IDS). A synthetic presentation of each theory and their connections shows how the activity of netw...

  13. LTE for Railways: Impact on Performance of ETCS Railway Signaling

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José

    2014-01-01

    The Global System for Mobile Communications-Railways (GSM-R) is an obsolete mobile technology with considerable shortcomings in terms of capacity and data transmission capabilities. Because of these shortcomings, GSM-R is becoming the element limiting the number of running trains in areas with high...... train concentration, such as major train stations. Moreover, GSM-R cannot support advanced data services. Hence, modern technologies, such as long-term evolution (LTE), have to be evaluated as possible railway communication technologies to replace GSM-R in the future. This article analyzes...... the characteristics of the LTE railway radio access network in terms of eNodeB (LTE base station) density and eNodeB transmission power. Based on this analysis, a set of computer-based simulation scenarios (e.g., OPNET) with varying numbers of eNodeBs is evaluated regarding the achieved transfer delay and data...

  14. The DREME Network: Research and Interventions in Early Childhood Mathematics.

    Science.gov (United States)

    Day-Hess, Crystal; Clements, Douglas H

    2017-01-01

    The DREME Network was created to advance the field of early mathematics research and improves the opportunities to develop math competencies offered to children birth through age 8 years, with an emphasis on the preschool years. All four main Network projects will have implications for interventions. Section 1 introduces the Network and its four projects. The remainder of the chapter focuses on one of these four projects, Making More of Math (MMM), in depth. MMM is directly developing an intervention for children, based on selecting high-quality instructional activities culled from the burgeoning curriculum resources. We first report a review of 457 activities from 6 research-based curricula, which describes the number of activities by content focus, type (nature), and setting of each activity. Given the interest in higher-order thinking skills and self-regulation, we then identified activities that had the potential to, develop both mathematics and executive function (EF) proficiencies. We rated these, selecting the top 10 for extensive coding by mathematics content and EF processes addressed. We find a wide divergence across curricula in all these categories and provide comprehensive reports for those interested in selecting, using, or developing early mathematics curricula. © 2017 Elsevier Inc. All rights reserved.

  15. Improving the urban green system and green network through the rehabilitation of railway rust areas

    Directory of Open Access Journals (Sweden)

    Hutter Dóra

    2014-11-01

    Full Text Available The Industrial Revolution had a negative impact on both the city and the environment. By the second half of the 19th century, the urban erosion of industrial cities cried for direct intervention and curing. The methods developed either along an urban or an anti-urban philosophy: they resulted in the new models of green belt systems aimed at solving all the main urban problems with restructuring the urban fabric, controlling the urban spread into the rural landscape, the lack of green areas and open spaces for recreation and social life, and the lack of green spaces for ventilation. Nowadays, the major cities and capitals around the globe are competing for titles such as healthier, more liveable or even greener city. Given the unfortunate attributes of the urban structure in the historical cities, the development of new transportation sites or green areas is an extremely difficult issue. On the other hand, in the big cities, the brownfield sites are considered as reserve areas for sustainable urban development. Reusing the brownfields and rust areas is already a land saving urban development approach and in case of a complex and ecological urban rehabilitation it can underlie the development of an efficient urban green system and green network.

  16. A Mathematical Model to Improve the Performance of Logistics Network

    Directory of Open Access Journals (Sweden)

    Muhammad Izman Herdiansyah

    2012-01-01

    Full Text Available The role of logistics nowadays is expanding from just providing transportation and warehousing to offering total integrated logistics. To remain competitive in the global market environment, business enterprises need to improve their logistics operations performance. The improvement will be achieved when we can provide a comprehensive analysis and optimize its network performances. In this paper, a mixed integer linier model for optimizing logistics network performance is developed. It provides a single-product multi-period multi-facilities model, as well as the multi-product concept. The problem is modeled in form of a network flow problem with the main objective to minimize total logistics cost. The problem can be solved using commercial linear programming package like CPLEX or LINDO. Even in small case, the solver in Excel may also be used to solve such model.Keywords: logistics network, integrated model, mathematical programming, network optimization

  17. Genetic demographic networks: Mathematical model and applications.

    Science.gov (United States)

    Kimmel, Marek; Wojdyła, Tomasz

    2016-10-01

    Recent improvement in the quality of genetic data obtained from extinct human populations and their ancestors encourages searching for answers to basic questions regarding human population history. The most common and successful are model-based approaches, in which genetic data are compared to the data obtained from the assumed demography model. Using such approach, it is possible to either validate or adjust assumed demography. Model fit to data can be obtained based on reverse-time coalescent simulations or forward-time simulations. In this paper we introduce a computational method based on mathematical equation that allows obtaining joint distributions of pairs of individuals under a specified demography model, each of them characterized by a genetic variant at a chosen locus. The two individuals are randomly sampled from either the same or two different populations. The model assumes three types of demographic events (split, merge and migration). Populations evolve according to the time-continuous Moran model with drift and Markov-process mutation. This latter process is described by the Lyapunov-type equation introduced by O'Brien and generalized in our previous works. Application of this equation constitutes an original contribution. In the result section of the paper we present sample applications of our model to both simulated and literature-based demographies. Among other we include a study of the Slavs-Balts-Finns genetic relationship, in which we model split and migrations between the Balts and Slavs. We also include another example that involves the migration rates between farmers and hunters-gatherers, based on modern and ancient DNA samples. This latter process was previously studied using coalescent simulations. Our results are in general agreement with the previous method, which provides validation of our approach. Although our model is not an alternative to simulation methods in the practical sense, it provides an algorithm to compute pairwise

  18. Edmodo social learning network for elementary school mathematics learning

    Science.gov (United States)

    Ariani, Y.; Helsa, Y.; Ahmad, S.; Prahmana, RCI

    2017-12-01

    A developed instructional media can be as printed media, visual media, audio media, and multimedia. The development of instructional media can also take advantage of technological development by utilizing Edmodo social network. This research aims to develop a digital classroom learning model using Edmodo social learning network for elementary school mathematics learning which is practical, valid and effective in order to improve the quality of learning activities. The result of this research showed that the prototype of mathematics learning device for elementary school students using Edmodo was in good category. There were 72% of students passed the assessment as a result of Edmodo learning. Edmodo has become a promising way to engage students in a collaborative learning process.

  19. The Design and Implementation of Smart Monitoring System for Large-Scale Railway Maintenance Equipment Cab Based on ZigBee Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Hairui Wang

    2014-06-01

    Full Text Available In recent years, organizations use IEEE 802.15.4 and ZigBee technology to deliver solution in variety areas including home environment monitoring. ZigBee technology has advantages on low-cost, low power consumption and self-forming. With the rapid expansion of the Internet, there is the requirement for remote monitoring large-scale railway maintenance equipment cab. This paper discusses the disadvantages of the existing smart monitoring system, and proposes a solution. A ZigBee wireless sensor network smart monitoring system and Wi-Fi network is integrated through a home gateway to increase the system flexibility. At the same time the home gateway cooperated with a pre- processing system provide a flexible user interface, and the security and safety of the smart monitoring system. To testify the efficiency of the proposed system, the temperature and humidity sensors and light sensors have developed and evaluated in the smart monitoring system.

  20. Mathematical model of transmission network static state estimation

    Directory of Open Access Journals (Sweden)

    Ivanov Aleksandar

    2012-01-01

    Full Text Available In this paper the characteristics and capabilities of the power transmission network static state estimator are presented. The solving process of the mathematical model containing the measurement errors and their processing is developed. To evaluate difference between the general model of state estimation and the fast decoupled state estimation model, the both models are applied to an example, and so derived results are compared.

  1. A mathematical programming approach for sequential clustering of dynamic networks

    Science.gov (United States)

    Silva, Jonathan C.; Bennett, Laura; Papageorgiou, Lazaros G.; Tsoka, Sophia

    2016-02-01

    A common analysis performed on dynamic networks is community structure detection, a challenging problem that aims to track the temporal evolution of network modules. An emerging area in this field is evolutionary clustering, where the community structure of a network snapshot is identified by taking into account both its current state as well as previous time points. Based on this concept, we have developed a mixed integer non-linear programming (MINLP) model, SeqMod, that sequentially clusters each snapshot of a dynamic network. The modularity metric is used to determine the quality of community structure of the current snapshot and the historical cost is accounted for by optimising the number of node pairs co-clustered at the previous time point that remain so in the current snapshot partition. Our method is tested on social networks of interactions among high school students, college students and members of the Brazilian Congress. We show that, for an adequate parameter setting, our algorithm detects the classes that these students belong more accurately than partitioning each time step individually or by partitioning the aggregated snapshots. Our method also detects drastic discontinuities in interaction patterns across network snapshots. Finally, we present comparative results with similar community detection methods for time-dependent networks from the literature. Overall, we illustrate the applicability of mathematical programming as a flexible, adaptable and systematic approach for these community detection problems. Contribution to the Topical Issue "Temporal Network Theory and Applications", edited by Petter Holme.

  2. In search of a railway Europe : transnational railway developments in interwar Europe

    NARCIS (Netherlands)

    Anastasiadou, E.

    2009-01-01

    Most conventional histories that address the creation and development of railway networks start from national developments. Recent scholarship on this topic, however, has stressed the importance of formulating a transnational perspective on technological developments and infrastructural developments

  3. Development of a guide for prioritization of railway bridges for repair and replacement.

    Science.gov (United States)

    2013-09-01

    The objective of this study was to develop evaluation bases for the repair, rehabilitation, and replacement of existing : railway bridges. Considering the importance of bridges to the railway network, the research involved the review and : analysis o...

  4. Traffic and transport technology-road, railway, and water-borne transportation

    Science.gov (United States)

    1990-01-01

    This is "Part 2: Case Studies - Chapter 9" of the book, "The Japanese Experience in Technology", and includes the following subsections: Modernization and the railway; The transportation network; Issues in railway policy; Original design and producti...

  5. Communication Technologies Support to Railway Infrastructure and Operations

    DEFF Research Database (Denmark)

    Sniady, Aleksander

    GSM-Railways (GSM-R), which is state-of-the-art railway mobile communication technology, is gradually replacing legacy analogue radio systems. Although GSM-R is an unquestionable achievement in terms of European railway interoperability, from a telecommunication point of view, it is an obsolete...... are considered to replace GSM-R in the future. This thesis is focused on Long Term Evolution (LTE) as one of the most likely successors to GSM-R. As a technology designed for commercial purposes, LTE has to be investigated specifically in railway environment. Using computer-based simulations, the LTE network...... important railway applications: European Train Control System (ETCS) signalling and railway-specific voice communication. Therefore, LTE is technically capable of replacing GSM-R as the communication network for the European Rail Traffic Management System (ERTMS). Moreover, the simulation results show...

  6. Instrumentation for Scientific Computing in Neural Networks, Information Science, Artificial Intelligence, and Applied Mathematics.

    Science.gov (United States)

    1987-10-01

    include Security Classification) Instrumentation for scientific computing in neural networks, information science, artificial intelligence, and...instrumentation grant to purchase equipment for support of research in neural networks, information science, artificail intellignece , and applied mathematics...in Neural Networks, Information Science, Artificial Intelligence, and Applied Mathematics Contract AFOSR 86-0282 Principal Investigator: Stephen

  7. Mathematical programs with complementarity constraints in traffic and telecommunications networks.

    Science.gov (United States)

    Ralph, Daniel

    2008-06-13

    Given a suitably parametrized family of equilibrium models and a higher level criterion by which to measure an equilibrium state, mathematical programs with equilibrium constraints (MPECs) provide a framework for improving or optimizing the equilibrium state. An example is toll design in traffic networks, which attempts to reduce total travel time by choosing which arcs to toll and what toll levels to impose. Here, a Wardrop equilibrium describes the traffic response to each toll design. Communication networks also have a deep literature on equilibrium flows that suggest some MPECs. We focus on mathematical programs with complementarity constraints (MPCCs), a subclass of MPECs for which the lower level equilibrium system can be formulated as a complementarity problem and therefore, importantly, as a nonlinear program (NLP). Although MPECs and MPCCs are typically non-convex, which is a consequence of the upper level objective clashing with the users' objectives in the lower level equilibrium program, the last decade of research has paved the way for finding local solutions of MPCCs via standard NLP techniques.

  8. Electrical railway transportation systems

    CERN Document Server

    Brenna, Morris; Zaninelli, Dario

    2018-01-01

    Allows the reader to deepen their understanding of various technologies for both fixed power supply installations of railway systems and for railway rolling stock. This book explores the electric railway systems that play a crucial role in the mitigation of congestion and pollution caused by road traffic. It is divided into two parts: the first covering fixed power supply systems, and the second concerning the systems for railway rolling stock. In particular, after a historical introduction to the framework of technological solutions in current use, the authors investigate electrification systems for the power supply of rail vehicles, trams, and subways. Electrical Railway Transportation Systems explores the direct current systems used throughout the world for urban and suburban transport, which are also used in various countries for regional transport. It provides a study of alternating current systems, whether for power supply frequency or for special railway frequency, that are used around the world for ...

  9. A three-level framework for performance-based railway timetabling

    NARCIS (Netherlands)

    Goverde, R.M.P.; Besinovic, N.; Binder, A.; Cacchiani, V.; Quaglietta, E.; Roberti, R.; Toth, P.

    2015-01-01

    The performance of railway operations depends highly on the quality of the railway timetable. In particular for dense railway networks it can be a challenge to obtain a stable robust conflict-free and energy-efficient timetable with acceptable infrastructure occupation and short travel times. This

  10. Routing trains through railway junctions: A new set-packing approach

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Ryan, David

    2011-01-01

    The problem of routing trains through railway junctions is an integral part of railway operations. Large junctions are highly interconnected networks of track where multiple railway lines merge, intersect, and split. The number of possible routings makes this a very complicated problem. We show h...

  11. Railway Reform in China.

    OpenAIRE

    Wu, J. H.; Nash, C.

    1998-01-01

    The purpose of this working paper is to consider the current situation of Chinese Railways, the progress of reforms to date, and possible future developments. The first section describes the current problems of Chinese Railways, as a vast organisation subject to strong central control, facing enormous and rapidly growing demands which it is unable to satisfy. The progress of reform in Chinese Railways to date, and in particular the Economic Contract Responsibility System instituted in the lat...

  12. Improving Punctuality and Transfer Reliability by Railway Timetable Optimization

    NARCIS (Netherlands)

    Goverde, R.M.P.

    1999-01-01

    The Dutch railway network is operated close to capacity with the current safety system. This leaves little space for control by process operators by which a delayed train can cause severe delay propagation. The NS currently invest a large amount in punctuality improvement of the railway operations.

  13. A Domain-Specific Language for Railway Interlocking Systems

    DEFF Research Database (Denmark)

    Vu, Linh Hong; Haxthausen, Anne Elisabeth; Peleska, Jan

    2014-01-01

    ). Furthermore, the paper describes an interlocking table generator (ITG) that generates automatically a well-formed interlocking table from a well-formed railway network layout. Experiments with the DSL and ITG using the RAISE tools and the C++ implementation show that the use of the DSL and ITG can increase...... the productivity and significantly reduce errors in the specifications of railway interlocking systems....

  14. Railway Endowment in Italy’s Provinces, 1839-1913

    NARCIS (Netherlands)

    Groote, Peter D.; Ciccarelli, Carlo

    This paper presents new annual estimates of railway extension in Italian provinces at 1913 borders for the period 1839-1913. The main operator of the Italian railway network (Ferrovie dello Stato) published in 1911 a unique set of homogeneous historical five year maps illustrating the routes of

  15. Mathematical inference and control of molecular networks from perturbation experiments

    Science.gov (United States)

    Mohammed-Rasheed, Mohammed

    One of the main challenges facing biologists and mathematicians in the post genomic era is to understand the behavior of molecular networks and harness this understanding into an educated intervention of the cell. The cell maintains its function via an elaborate network of interconnecting positive and negative feedback loops of genes, RNA and proteins that send different signals to a large number of pathways and molecules. These structures are referred to as genetic regulatory networks (GRNs) or molecular networks. GRNs can be viewed as dynamical systems with inherent properties and mechanisms, such as steady-state equilibriums and stability, that determine the behavior of the cell. The biological relevance of the mathematical concepts are important as they may predict the differentiation of a stem cell, the maintenance of a normal cell, the development of cancer and its aberrant behavior, and the design of drugs and response to therapy. Uncovering the underlying GRN structure from gene/protein expression data, e.g., microarrays or perturbation experiments, is called inference or reverse engineering of the molecular network. Because of the high cost and time consuming nature of biological experiments, the number of available measurements or experiments is very small compared to the number of molecules (genes, RNA and proteins). In addition, the observations are noisy, where the noise is due to the measurements imperfections as well as the inherent stochasticity of genetic expression levels. Intra-cellular activities and extra-cellular environmental attributes are also another source of variability. Thus, the inference of GRNs is, in general, an under-determined problem with a highly noisy set of observations. The ultimate goal of GRN inference and analysis is to be able to intervene within the network, in order to force it away from undesirable cellular states and into desirable ones. However, it remains a major challenge to design optimal intervention strategies

  16. Demystifying the cytokine network: Mathematical models point the way.

    Science.gov (United States)

    Morel, Penelope A; Lee, Robin E C; Faeder, James R

    2017-10-01

    Cytokines provide the means by which immune cells communicate with each other and with parenchymal cells. There are over one hundred cytokines and many exist in families that share receptor components and signal transduction pathways, creating complex networks. Reductionist approaches to understanding the role of specific cytokines, through the use of gene-targeted mice, have revealed further complexity in the form of redundancy and pleiotropy in cytokine function. Creating an understanding of the complex interactions between cytokines and their target cells is challenging experimentally. Mathematical and computational modeling provides a robust set of tools by which complex interactions between cytokines can be studied and analyzed, in the process creating novel insights that can be further tested experimentally. This review will discuss and provide examples of the different modeling approaches that have been used to increase our understanding of cytokine networks. This includes discussion of knowledge-based and data-driven modeling approaches and the recent advance in single-cell analysis. The use of modeling to optimize cytokine-based therapies will also be discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Long-Term Structural Health Monitoring System for a High-Speed Railway Bridge Structure

    Science.gov (United States)

    Wu, Lai-Yi

    2015-01-01

    Nanjing Dashengguan Bridge, which serves as the shared corridor crossing Yangtze River for both Beijing-Shanghai high-speed railway and Shanghai-Wuhan-Chengdu railway, is the first 6-track high-speed railway bridge with the longest span throughout the world. In order to ensure safety and detect the performance deterioration during the long-time service of the bridge, a Structural Health Monitoring (SHM) system has been implemented on this bridge by the application of modern techniques in sensing, testing, computing, and network communication. The SHM system includes various sensors as well as corresponding data acquisition and transmission equipment for automatic data collection. Furthermore, an evaluation system of structural safety has been developed for the real-time condition assessment of this bridge. The mathematical correlation models describing the overall structural behavior of the bridge can be obtained with the support of the health monitoring system, which includes cross-correlation models for accelerations, correlation models between temperature and static strains of steel truss arch, and correlation models between temperature and longitudinal displacements of piers. Some evaluation results using the mean value control chart based on mathematical correlation models are presented in this paper to show the effectiveness of this SHM system in detecting the bridge's abnormal behaviors under the varying environmental conditions such as high-speed trains and environmental temperature. PMID:26451387

  18. Long-Term Structural Health Monitoring System for a High-Speed Railway Bridge Structure

    Directory of Open Access Journals (Sweden)

    You-Liang Ding

    2015-01-01

    Full Text Available Nanjing Dashengguan Bridge, which serves as the shared corridor crossing Yangtze River for both Beijing-Shanghai high-speed railway and Shanghai-Wuhan-Chengdu railway, is the first 6-track high-speed railway bridge with the longest span throughout the world. In order to ensure safety and detect the performance deterioration during the long-time service of the bridge, a Structural Health Monitoring (SHM system has been implemented on this bridge by the application of modern techniques in sensing, testing, computing, and network communication. The SHM system includes various sensors as well as corresponding data acquisition and transmission equipment for automatic data collection. Furthermore, an evaluation system of structural safety has been developed for the real-time condition assessment of this bridge. The mathematical correlation models describing the overall structural behavior of the bridge can be obtained with the support of the health monitoring system, which includes cross-correlation models for accelerations, correlation models between temperature and static strains of steel truss arch, and correlation models between temperature and longitudinal displacements of piers. Some evaluation results using the mean value control chart based on mathematical correlation models are presented in this paper to show the effectiveness of this SHM system in detecting the bridge’s abnormal behaviors under the varying environmental conditions such as high-speed trains and environmental temperature.

  19. Railway infrastructure security

    CERN Document Server

    Sforza, Antonio; Vittorini, Valeria; Pragliola, Concetta

    2015-01-01

    This comprehensive monograph addresses crucial issues in the protection of railway systems, with the objective of enhancing the understanding of railway infrastructure security. Based on analyses by academics, technology providers, and railway operators, it explains how to assess terrorist and criminal threats, design countermeasures, and implement effective security strategies. In so doing, it draws upon a range of experiences from different countries in Europe and beyond. The book is the first to be devoted entirely to this subject. It will serve as a timely reminder of the attractiveness of the railway infrastructure system as a target for criminals and terrorists and, more importantly, as a valuable resource for stakeholders and professionals in the railway security field aiming to develop effective security based on a mix of methodological, technological, and organizational tools. Besides researchers and decision makers in the field, the book will appeal to students interested in critical infrastructur...

  20. Mathematical models of electrical network systems theory and applications : an introduction

    CERN Document Server

    Kłos, Andrzej

    2017-01-01

    This book is for all those who are looking for a non-conventional mathematical model of electrical network systems. It presents a modern approach using linear algebra and derives various commonly unknown quantities and interrelations of network analysis. It also explores some applications of algebraic network model of and solves some examples of previously unsolved network problems in planning and operation of network systems. Complex mathematical aspects are illustrated and described in a way that is understandable for non-mathematicians. Discussing interesting concepts and practically useful methods of network analysis, it is a valuable resource for lecturers, students, engineers and research workers. .

  1. Verification of temporal-causal network models by mathematical analysis

    Directory of Open Access Journals (Sweden)

    Jan Treur

    2016-04-01

    Full Text Available Abstract Usually dynamic properties of models can be analysed by conducting simulation experiments. But sometimes, as a kind of prediction properties can also be found by calculations in a mathematical manner, without performing simulations. Examples of properties that can be explored in such a manner are: whether some values for the variables exist for which no change occurs (stationary points or equilibria, and how such values may depend on the values of the parameters of the model and/or the initial values for the variables whether certain variables in the model converge to some limit value (equilibria and how this may depend on the values of the parameters of the model and/or the initial values for the variables whether or not certain variables will show monotonically increasing or decreasing values over time (monotonicity how fast a convergence to a limit value takes place (convergence speed whether situations occur in which no convergence takes place but in the end a specific sequence of values is repeated all the time (limit cycle Such properties found in an analytic mathematical manner can be used for verification of the model by checking them for the values observed in simulation experiments. If one of these properties is not fulfilled, then there will be some error in the implementation of the model. In this paper some methods to analyse such properties of dynamical models will be described and illustrated for the Hebbian learning model, and for dynamic connection strengths in social networks. The properties analysed by the methods discussed cover equilibria, increasing or decreasing trends, recurring patterns (limit cycles, and speed of convergence to equilibria.

  2. Train-Network Interactions and Stability Evaluation in High-Speed Railways--Part I: Phenomena and Modeling

    DEFF Research Database (Denmark)

    Hu, Haitao; Tao, Haidong; Blaabjerg, Frede

    2018-01-01

    of the electric trains and traction network are equally modeled. In which, an impedance-based input behavior of the train is fully investigated with considering available controllers and their parameters in DQ-domain. While, the entire traction network, including traction transformer, catenary, supply lines......, is represented in a frequency-domain nodal matrix. Furthermore, the impedance-frequency responses of both electric train and traction network are measured and validated through frequency scan method. Finally, a generalized train-network simulation and experimental systems are proposed for verifying...

  3. Railway capacity and expansion analysis using time discretized paths

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander; Pisinger, David; Lusby, Richard Martin

    2017-01-01

    of railway freight transportation on a long term strategic level. The model uses an hourly time discretization and analyses the impact of railway network expansions based on future demand forecasts. It provides an optimal macroscopic freight train schedule and can indicate the time and place of any...... variable penalties for the different passenger busy time slots. As part of a European Union project, all models are applied to a realistic case study that focuses on analyzing the capacity of railway network, in Denmark and Southern Sweden using demand forecasts for 2030. Results suggest that informative...

  4. Resolving instability in railway timetabling problems

    NARCIS (Netherlands)

    Besinovic, Nikola; Quaglietta, E.; Goverde, R.M.P.

    A growth of the railway transportation demand is forecasted in the next decades which needs an increase of network capacity. Where possible, infrastructure upgrading can release extra capacity, although in some cases this is not enough to satisfy the entire transportation demand unless optimised

  5.  Railway Reforms

    DEFF Research Database (Denmark)

    Asmild, Mette; Holvad, Torben; Hougaard, Jens Leth

    This paper considers railway operations in 23 European countries during 1995-2001, where a series of reform initiatives were launched by the European Commission, and analyses whether these reform initiatives improved the operating efficiency of the railways. Efficiency is measured using Multi......-directional Efficiency Analysis, which enables investigation of how railway reforms affect the inefficiencies of specific cost drivers. The main findings are that the reform initiatives generally improve operating efficiency but potentially differently for different cost drivers. Specifically, the paper provides clear...

  6. Causal Analysis of Railway Running Delays

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Nielsen, Otto Anker; Harrod, Steven

    Operating delays and network propagation are inherent characteristics of railway operations. These are traditionally reduced by provision of time supplements or “slack” in railway timetables and operating plans. Supplement allocation policies must trade off reliability in the service commitments...... Denmark (the Danish infrastructure manager). The statistical analysis of the data identifies the minimum running times and the scheduled running time supplements and investigates the evolution of train delays along given train paths. An improved allocation of time supplements would result in smaller...

  7. THE RAILWAYS THE

    African Journals Online (AJOL)

    Sout'h Africa's armed forces were small, and their material resources ... scheme, contingency planning proceeded. On the outbreak of ... hannesburg); a Railway Operating Company; a Mechanical .... ded his verdict that from the points of view.

  8. The Mathematics of Networks Science: Scale-Free, Power-Law Graphs and Continuum Theoretical Analysis

    Science.gov (United States)

    Padula, Janice

    2012-01-01

    When hoping to initiate or sustain students' interest in mathematics teachers should always consider relevance, relevance to students' lives and in the middle and later years of instruction in high school and university, accessibility. A topic such as the mathematics behind networks science, more specifically scale-free graphs, is up-to-date,…

  9. Separation of network and operation in the railway sector. A study of ownership unbundling under European law; Die Trennung von Netz und Betrieb im Eisenbahnsektor. Eine europarechtliche Untersuchung des Ownership Unbundling

    Energy Technology Data Exchange (ETDEWEB)

    Helmstaedter, Felix

    2011-07-01

    This publication shows how throughout Europe the process of market liberalisation in the railway sector is currently going through a decisive phase. In contrast to other network industries, especially in the telecommunication and energy sectors, the liberalisation of the railway sector is still in its beginnings. These network industries underwent full privatisation of what were formerly state monopolies. This gave rise to services markets operating in a competitive environment, the most impressive example of which is the telecommunications sector. Compared with its other forms the concept of separating ownership of a network from that of its operation, also referred to as ownership unbundling, is the most radical form of unbundling. This is not the least reason why it is one of the most controversial procedures for privatising vertically integrated network monopolies. There are sufficient practical examples and theories of economic competition to motivate a study of this model from the perspective of European law. This provides the backdrop to the present study, which investigates how a consistent implementation of unbundling stipulations can contribute to the realisation of a single European market, which is the original motive and purpose of liberalisation. It inquires in particular into the degree to which, compared with other models, ownership unbundling can be regarded as particularly suitable if not as the only structural model suitable for this purpose.

  10. Mathematics education as a network of social practices

    DEFF Research Database (Denmark)

    Valero, Paola

    2010-01-01

    Based on an analysis of mathematics education research as an academic field and on current social, political and economic transformations in many European countries, I would argue for the need to rethink and enlarge definitions and views of mathematics education as a scientific field of study in ...

  11. Vulnerability assessment and mitigation for the Chinese railway system under floods

    International Nuclear Information System (INIS)

    Hong, Liu; Ouyang, Min; Peeta, Srinivas; He, Xiaozheng; Yan, Yongze

    2015-01-01

    The economy of China and the travel needs of its citizens depend significantly on the continuous and reliable services provided by its railway system. However, this system is subject to frequent natural hazards, such as floods, earthquakes, and debris flow. A mechanism to assess the railway system vulnerability under these hazards and the design of effective vulnerability mitigation strategies are essential to the reliable functioning of the railway system. This article proposes a comprehensive methodology to quantitatively assess the railway system vulnerability under floods using historical data and GIS technology. The proposed methodology includes a network representation of the railway system, the generation of flood event scenarios, a method to estimate railway link vulnerability, and a quantitative vulnerability value computation approach. The railway system vulnerability is evaluated in terms of its service disruption related to the number of interrupted trains and the durations of interruption. A maintenance strategy to mitigate vulnerability is proposed that simultaneously considers link vulnerability and number of trains using it. Numerical experiments show that the flood-induced vulnerability of the proposed representation of the Chinese railway system reaches its maximum monthly value in July, and the proposed vulnerability mitigation strategy is more effective compared to other strategies. - Highlights: • We propose a methodology to assess flood-induced railway system vulnerability. • Railway system vulnerability is evaluated in terms of its service disruption. • Chinese railway system reaches its maximum monthly vulnerability in July. • We propose an effective maintenance strategy considering link vulnerability and burden

  12. DC Cable for Railway

    Science.gov (United States)

    Tomita, Masaru

    The development of a superconducting cable for railways has commenced, assuming that a DC transmission cable will be used for electric trains. The cable has been fabricated based on the results of current testing of a superconducting wire, and various evaluation tests have been performed to determine the characteristics of the cable. A superconducting transmission cable having zero electrical resistance and suitable for railway use is expected to enhance regeneration efficiency, reduce power losses, achieve load leveling and integration of sub-stations, and reduce rail potential.

  13. Mathematical modelling of complex contagion on clustered networks

    Science.gov (United States)

    O'sullivan, David J.; O'Keeffe, Gary; Fennell, Peter; Gleeson, James

    2015-09-01

    The spreading of behavior, such as the adoption of a new innovation, is influenced bythe structure of social networks that interconnect the population. In the experiments of Centola (Science, 2010), adoption of new behavior was shown to spread further and faster across clustered-lattice networks than across corresponding random networks. This implies that the “complex contagion” effects of social reinforcement are important in such diffusion, in contrast to “simple” contagion models of disease-spread which predict that epidemics would grow more efficiently on random networks than on clustered networks. To accurately model complex contagion on clustered networks remains a challenge because the usual assumptions (e.g. of mean-field theory) regarding tree-like networks are invalidated by the presence of triangles in the network; the triangles are, however, crucial to the social reinforcement mechanism, which posits an increased probability of a person adopting behavior that has been adopted by two or more neighbors. In this paper we modify the analytical approach that was introduced by Hebert-Dufresne et al. (Phys. Rev. E, 2010), to study disease-spread on clustered networks. We show how the approximation method can be adapted to a complex contagion model, and confirm the accuracy of the method with numerical simulations. The analytical results of the model enable us to quantify the level of social reinforcement that is required to observe—as in Centola’s experiments—faster diffusion on clustered topologies than on random networks.

  14. Mathematical modelling of complex contagion on clustered networks

    Directory of Open Access Journals (Sweden)

    David J. P. O'Sullivan

    2015-09-01

    Full Text Available The spreading of behavior, such as the adoption of a new innovation, is influenced bythe structure of social networks that interconnect the population. In the experiments of Centola (Science, 2010, adoption of new behavior was shown to spread further and faster across clustered-lattice networks than across corresponding random networks. This implies that the complex contagion effects of social reinforcement are important in such diffusion, in contrast to simple contagion models of disease-spread which predict that epidemics would grow more efficiently on random networks than on clustered networks. To accurately model complex contagion on clustered networks remains a challenge because the usual assumptions (e.g. of mean-field theory regarding tree-like networks are invalidated by the presence of triangles in the network; the triangles are, however, crucial to the social reinforcement mechanism, which posits an increased probability of a person adopting behavior that has been adopted by two or more neighbors. In this paper we modify the analytical approach that was introduced by Hebert-Dufresne et al. (Phys. Rev. E, 2010, to study disease-spread on clustered networks. We show how the approximation method can be adapted to a complex contagion model, and confirm the accuracy of the method with numerical simulations. The analytical results of the model enable us to quantify the level of social reinforcement that is required to observe—as in Centola’s experiments—faster diffusion on clustered topologies than on random networks.

  15. Recent advances in the fundamental understanding of railway vehicle dynamics

    DEFF Research Database (Denmark)

    True, Hans

    2006-01-01

    The topic of this article is the calculation of the critical speed for railway vehicles. It is emphasised that it is misleading to formulate the mathematical problem as a stability problem. It must correctly be formulated as a problem of existence of coexisting solutions to the full non-linear dy......The topic of this article is the calculation of the critical speed for railway vehicles. It is emphasised that it is misleading to formulate the mathematical problem as a stability problem. It must correctly be formulated as a problem of existence of coexisting solutions to the full non......-linear dynamical problem. The lowest speed at which there exist more critical speed in road tests. A couple of examples show applications of the method to various dynamical models of railway vehicles. Freight wagons are treated in the end of the article because the dry friction damping with stick-slip and end...

  16. Capacity Utilization in European Railways

    DEFF Research Database (Denmark)

    Khadem Sameni, Melody; Landex, Alex

    2013-01-01

    and unprecedented approach for this aim. Relative operational efficiency of 24 European railways in capacity utilization is studied for the first time by data envelopment analysis (DEA). It deviates from previous applications of DEA in the railway industry that are conducted to analyze cost efficiency of railways....... Six DEA models quantify various aspects of micro, macro and quality of railway capacity utilization in these countries. New inputs like gross domestic product, population and area of the country help to provide a better picture of the status of railways. Passenger satisfaction data about different...... aspects of railway services in European countries has recently been quantified by European commission and are used for the first time in the literature. Invaluable insights can be inferred from the results which can provide a ground basis for railway practitioners and policy makers....

  17. Mathematical Models by Quality of Service Driven Routing in Networks

    National Research Council Canada - National Science Library

    Gelenbe, E

    2005-01-01

    Very large networks with varying topologies, unreliable components, and highly time varying traffic, are not amenable to traditional techniques of analysis based on traffic engineering and simulations...

  18. Mathematical Models for Quality of Service Driven Routing in Networks

    National Research Council Canada - National Science Library

    Gelenbe, E

    2005-01-01

    Very large networks with varying topologies, unreliable components, and highly time varying traffic, are not amenable to traditional techniques of analysis based on traffic engineering and simulations...

  19. Subcontracting Railway Maintenance

    DEFF Research Database (Denmark)

    Thommesen, Jacob

    2010-01-01

    railway infrastructure manager (InfraMan), whichis subcontracting maintenance tasks to other companies. InfraMan has implemented various central elements in managing their subcontractors. The latter are required to present a safety plan as part of their bid, they must be approved if they are to be awarded...

  20. The Instructional Network: Using Facebook to Enhance Undergraduate Mathematics Instruction

    Science.gov (United States)

    Gregory, Peter; Gregory, Karen; Eddy, Erik

    2014-01-01

    Facebook is a website with over one billion users worldwide that is synonymous with social-networking. However, in this study, Facebook is used as an "instructional network". Two sections of an undergraduate calculus course were used to study the effects of participating in a Facebook group devoted solely to instruction. One section was…

  1. Reliability analysis of maintenance operations for railway tracks

    International Nuclear Information System (INIS)

    Rhayma, N.; Bressolette, Ph.; Breul, P.; Fogli, M.; Saussine, G.

    2013-01-01

    Railway engineering is confronted with problems due to degradation of the railway network that requires important and costly maintenance work. However, because of the lack of knowledge on the geometrical and mechanical parameters of the track, it is difficult to optimize the maintenance management. In this context, this paper presents a new methodology to analyze the behavior of railway tracks. It combines new diagnostic devices which permit to obtain an important amount of data and thus to make statistics on the geometric and mechanical parameters and a non-intrusive stochastic approach which can be coupled with any mechanical model. Numerical results show the possibilities of this methodology for reliability analysis of different maintenance operations. In the future this approach will give important informations to railway managers to optimize maintenance operations using a reliability analysis

  2. Modeling track access charge to enhance railway industry performance

    Science.gov (United States)

    Berawi, Mohammed Ali; Miraj, Perdana; Berawi, Abdur Rohim Boy; Susantono, Bambang; Leviakangas, Pekka; Radiansyah, Hendra

    2017-11-01

    Indonesia attempts to improve nation's competitiveness by increasing the quality and the availability of railway network. However, the infrastructure improperly managed by the operator in terms of the technical issue. One of the reasons for this problem is an unbalanced value of infrastructure charge. In 2000's track access charge and infrastructure maintenance and operation for Indonesia railways are equal and despite current formula of the infrastructure charge, issues of transparency and accountability still in question. This research aims to produce an alternative scheme of track access charge by considering marginal cost plus markup (MC+) approach. The research combines qualitative and quantitative method through an in-depth interview and financial analysis. The result will generate alternative formula of infrastructure charge in Indonesia's railway industry. The simulation also conducted to estimate track access charge for the operator and to forecast government support in terms of subsidy. The result is expected to enhance railway industry performance and competitiveness.

  3. Synthesis of railway-signaling plans using reachability games

    DEFF Research Database (Denmark)

    Kasting, Patrick Frederik Soelmark; Hansen, Michael Reichhardt; Vester, Steen

    2016-01-01

    (the control system) controls signals and points and the universal player (the antagonistic environment) controls movement of trains. A winning strategy for the existential player provides a signaling plan that will safely guide trains through the network. The concepts from the railway network model......In this work, we show the feasibility of using functional programming (more specifically F#) in connection with gamebased methods for synthesis of correct-by-construction controllers (also called signaling plans) for railway networks. This is a massively resource-demanding application. A model...

  4. Practice Oriented Algorithmic Disruption Management in Passenger Railways

    NARCIS (Netherlands)

    J.C. Wagenaar (Joris)

    2016-01-01

    markdownabstractHow to deal with a disruption is a question railway companies face on a daily basis. This thesis focusses on the subject how to handle a disruption such that the passenger service is upheld as much as possible. The current mathematical models for disruption management can not yet be

  5. Mathematical Analysis of a PDE System for Biological Network Formation

    KAUST Repository

    Haskovec, Jan

    2015-02-04

    Motivated by recent physics papers describing rules for natural network formation, we study an elliptic-parabolic system of partial differential equations proposed by Hu and Cai [13, 15]. The model describes the pressure field thanks to Darcy\\'s type equation and the dynamics of the conductance network under pressure force effects with a diffusion rate D >= 0 representing randomness in the material structure. We prove the existence of global weak solutions and of local mild solutions and study their long term behavior. It turns out that, by energy dissipation, steady states play a central role to understand the network formation capacity of the system. We show that for a large diffusion coefficient D, the zero steady state is stable, while network formation occurs for small values of D due to the instability of the zero steady state, and the borderline case D = 0 exhibits a large class of dynamically stable (in the linearized sense) steady states.

  6. Mathematical Analysis of a PDE System for Biological Network Formation

    KAUST Repository

    Haskovec, Jan; Markowich, Peter A.; Perthame, Benoit

    2015-01-01

    Motivated by recent physics papers describing rules for natural network formation, we study an elliptic-parabolic system of partial differential equations proposed by Hu and Cai [13, 15]. The model describes the pressure field thanks to Darcy's type

  7. Mathematics

    CERN Document Server

    Eringen, A Cemal

    2013-01-01

    Continuum Physics: Volume 1 - Mathematics is a collection of papers that discusses certain selected mathematical methods used in the study of continuum physics. Papers in this collection deal with developments in mathematics in continuum physics and its applications such as, group theory functional analysis, theory of invariants, and stochastic processes. Part I explains tensor analysis, including the geometry of subspaces and the geometry of Finsler. Part II discusses group theory, which also covers lattices, morphisms, and crystallographic groups. Part III reviews the theory of invariants th

  8. Current and future flood risk to railway infrastructure in Europe

    Science.gov (United States)

    Bubeck, Philip; Kellermann, Patric; Alfieri, Lorenzo; Feyen, Luc; Dillenardt, Lisa; Thieken, Annegret H.

    2017-04-01

    Railway infrastructure plays an important role in the transportation of freight and passengers across the European Union. According to Eurostat, more than four billion passenger-kilometres were travelled on national and international railway lines of the EU28 in 2014. To further strengthen transport infrastructure in Europe, the European Commission will invest another € 24.05 billion in the transnational transport network until 2020 as part of its new transport infrastructure policy (TEN-T), including railway infrastructure. Floods pose a significant risk to infrastructure elements. Damage data of recent flood events in Europe show that infrastructure losses can make up a considerable share of overall losses. For example, damage to state and municipal infrastructure in the federal state of Saxony (Germany) accounted for nearly 60% of overall losses during the large-scale event in June 2013. Especially in mountainous areas with little usable space available, roads and railway lines often follow floodplains or are located along steep and unsteady slopes. In Austria, for instance, the flood of 2013 caused € 75 million of direct damage to railway infrastructure. Despite the importance of railway infrastructure and its exposure to flooding, assessments of potential damage and risk (i.e. probability * damage) are still in its infancy compared with other sectors, such as the residential or industrial sector. Infrastructure-specific assessments at the regional scale are largely lacking. Regional assessment of potential damage to railway infrastructure has been hampered by a lack of infrastructure-specific damage models and data availability. The few available regional approaches have used damage models that assess damage to various infrastructure elements (e.g. roads, railway, airports and harbours) using one aggregated damage function and cost estimate. Moreover, infrastructure elements are often considerably underrepresented in regional land cover data, such as

  9. Networks of Learning : Professional Association and the Continuing Education of Teachers of Mathematics in Pakistan

    DEFF Research Database (Denmark)

    Baber, Sikunder Ali

    " and shows how a number of professional associations have become as networks of learning to encourage the continuing professional education of both pre-service and in-service teachers in the context of Pakistan. A case of the Mathematics Association of Pakistan (MAP) as a Network of Learning is presented....... The formation and growth of this network can be viewed as developing insights into the improvement of mathematics education in the developing world. The contributions of the association may also add value to the learning of teacher colleagues in other parts of the world. This sharing of the experience may......Importance of the professional development of teachers has been recognized and research has contributed greatly in terms of proposing variety of approaches for the development of teachers,both pre-service and in-service. Among them, networking among teachers, teacher educators,curriculum developers...

  10. Geographic distribution of suicide and railway suicide in Belgium, 2008-2013: a principal component analysis.

    Science.gov (United States)

    Strale, Mathieu; Krysinska, Karolina; Overmeiren, Gaëtan Van; Andriessen, Karl

    2017-06-01

    This study investigated the geographic distribution of suicide and railway suicide in Belgium over 2008--2013 on local (i.e., district or arrondissement) level. There were differences in the regional distribution of suicide and railway suicides in Belgium over the study period. Principal component analysis identified three groups of correlations among population variables and socio-economic indicators, such as population density, unemployment, and age group distribution, on two components that helped explaining the variance of railway suicide at a local (arrondissement) level. This information is of particular importance to prevent suicides in high-risk areas on the Belgian railway network.

  11. Innovative Railway Stations

    Science.gov (United States)

    Rzepnicka, Sylwia; Załuski, Daniel

    2017-10-01

    In relation to modern demographic trends, evolving technologies and environment-friendly solutions increases the potential of rail considered as sustainable form of public transport. Contemporary tendencies of designing railway stations in Europe are focused on lowering energy consumption and reducing carbon emission. The main goal of the designers is to create a friendly and intuitive space for its users and at the same time a building that uses renewable energy sources and minimizes negative impact on the environment by the increase of biologically active areas, reuse of rainwater and greywater, innovative heating and cooling solutions and reduction of energy losses. The optimisation of a life circle in railway architecture introduces new approach to passenger service. Examples mentioned in the content of this article help to synthesize changes in approach to the design within the context of sustainability.

  12. Environmental risks of high-speed railway in China: Public participation, perception and trust

    NARCIS (Netherlands)

    He, G.; Mol, A.P.J.; Zhang, L.; Lu, Y.

    2015-01-01

    Two decades ago China entered an era with rapid expansion of transport infrastructure. In an ambitious plan on high-speed railway development, China plans to have the longest high-speed railway network by 2020. Social concerns and anxiety with the adverse environmental and social risks and impacts

  13. The role of the railways in the future of air transport

    NARCIS (Netherlands)

    Givoni, M.; Banister, D.

    2007-01-01

    The role of the railways in the air transport industry is usually limited to provision of access to airports. However, the development of high-speed rail networks and the congestion and environmental problems faced by the air transport industry suggest the railways could have a greater role in

  14. Second Best Decision Making of Railway Operators: How to fix Fares, Frequency and Vehicle Size

    NARCIS (Netherlands)

    Rietveld, Piet; Woudenberg, van Stefan

    2007-01-01

    Railway networks are characterised by variations in demand on different links. Optimal strategies therefore call for a differentiated treatment of fares, frequencies and vehicle sizes in various links. However, for several reasons, railway operators may apply uniform levels for these decision

  15. A Predictive Maintenance Model for Railway Tracks

    DEFF Research Database (Denmark)

    Li, Rui; Wen, Min; Salling, Kim Bang

    2015-01-01

    presents a mathematical model based on Mixed Integer Programming (MIP) which is designed to optimize the predictive railway tamping activities for ballasted track for the time horizon up to four years. The objective function is setup to minimize the actual costs for the tamping machine (measured by time......). Five technical and economic aspects are taken into account to schedule tamping: (1) track degradation of the standard deviation of the longitudinal level over time; (2) track geometrical alignment; (3) track quality thresholds based on the train speed limits; (4) the dependency of the track quality...

  16. Safety of Transmission in Railway Applications

    Directory of Open Access Journals (Sweden)

    Maria Franekova

    2003-01-01

    Full Text Available The paper deals with the problems of data security in safety - related transmission systems defined within railway process. It is intent on summary of treats and security tools against them within closed and open security systems. In details is analysed possibility of using channel coding techniques and cryptography mechanisms, which are defined according to norms EN 50159. For chosen security mechanisms are deal mathematical apparatus of probability of undetected error determination for channel decoders, relations for determination decipher encoder's complexity and error probability of cryptography code word.

  17. Mathematics

    CERN Document Server

    Stein, Sherman K

    2010-01-01

    Anyone can appreciate the beauty, depth, and vitality of mathematics with the help of this highly readable text, specially developed from a college course designed to appeal to students in a variety of fields. Readers with little mathematical background are exposed to a broad range of subjects chosen from number theory, topology, set theory, geometry, algebra, and analysis. Starting with a survey of questions on weight, the text discusses the primes, the fundamental theorem of arithmetic, rationals and irrationals, tiling, tiling and electricity, probability, infinite sets, and many other topi

  18. The Design and Implementation of Smart Monitoring System for Large-Scale Railway Maintenance Equipment Cab Based on ZigBee Wireless Sensor Network

    OpenAIRE

    Hairui Wang; Junfu Yu

    2014-01-01

    In recent years, organizations use IEEE 802.15.4 and ZigBee technology to deliver solution in variety areas including home environment monitoring. ZigBee technology has advantages on low-cost, low power consumption and self-forming. With the rapid expansion of the Internet, there is the requirement for remote monitoring large-scale railway maintenance equipment cab. This paper discusses the disadvantages of the existing smart monitoring system, and proposes a solution. A ZigBee wireless senso...

  19. Mathematics

    International Nuclear Information System (INIS)

    Demazure, M.

    1988-01-01

    The 1988 progress report of the Mathematics center (Polytechnic School, France), is presented. The Center is composed of different research teams: analysis, Riemann geometry, group theory, formal calculus and algorithm geometry, dynamical systems, topology and singularity. For each team, the members, the research topics, the national and international cooperations, are given. The papers concerning the investigations carried out in 1988, are listed [fr

  20. Generating a Networked Improvement Community to Improve Secondary Mathematics Teacher Preparation: Network Leadership, Organization, and Operation

    Science.gov (United States)

    Martin, W. Gary; Gobstein, Howard

    2015-01-01

    The Mathematics Teacher Education Partnership (MTE-Partnership) was formed to address the undersupply of new secondary mathematics teachers who are well prepared to help their students attain the goals of the Common Core State Standards and other college- and career-ready standards. This national consortium of more than 90 universities and 100…

  1. Road Network Extraction from Dsm by Mathematical Morphology and Reasoning

    Science.gov (United States)

    Li, Yan; Wu, Jianliang; Zhu, Lin; Tachibana, Kikuo

    2016-06-01

    The objective of this research is the automatic extraction of the road network in a scene of the urban area from a high resolution digital surface model (DSM). Automatic road extraction and modeling from remote sensed data has been studied for more than one decade. The methods vary greatly due to the differences of data types, regions, resolutions et al. An advanced automatic road network extraction scheme is proposed to address the issues of tedium steps on segmentation, recognition and grouping. It is on the basis of a geometric road model which describes a multiple-level structure. The 0-dimension element is intersection. The 1-dimension elements are central line and side. The 2-dimension element is plane, which is generated from the 1-dimension elements. The key feature of the presented approach is the cross validation for the three road elements which goes through the entire procedure of their extraction. The advantage of our model and method is that linear elements of the road can be derived directly, without any complex, non-robust connection hypothesis. An example of Japanese scene is presented to display the procedure and the performance of the approach.

  2. An innovative localisation algorithm for railway vehicles

    Science.gov (United States)

    Allotta, B.; D'Adamio, P.; Malvezzi, M.; Pugi, L.; Ridolfi, A.; Rindi, A.; Vettori, G.

    2014-11-01

    . The estimation strategy has good performance also under degraded adhesion conditions and could be put on board of high-speed railway vehicles; it represents an accurate and reliable solution. The IMU board is tested via a dedicated Hardware in the Loop (HIL) test rig: it includes an industrial robot able to replicate the motion of the railway vehicle. Through the generated experimental outputs the performances of the innovative localisation algorithm have been evaluated: the HIL test rig permitted to test the proposed algorithm, avoiding expensive (in terms of time and cost) on-track tests, obtaining encouraging results. In fact, the preliminary results show a significant improvement of the position and speed estimation performances compared to those obtained with SCMT algorithms, currently in use on the Italian railway network.

  3. Railway diagnosis of electric transport

    Directory of Open Access Journals (Sweden)

    Yushkov Vladimir Sergeevich

    2015-01-01

    Full Text Available The increase in noise level at cities is increasing the requirements to functional interaction of road users - pedestrians and drivers - with the parameters of the environment as a leading component of Afferentation synthesis in the complicated complex of locomotive activity. City noise is one of the most widespread factors of unfavorable living and working conditions. The noise of high intensity provokes diseases, lowers labor activity. At present, many large cities pay much attention to electric vehicles. The authors present an analysis of the poor state of tram track in areas of high noise and vibration of car and under-sleeper base design. A negative effect of noise and vibration on the formation of urban areas environment is shown as well as the impact of these conditions on the person. The advantages of the application of electric transport are specified, noise displacement curve of railway and under sleeper base is plotted depending on the frequency of the applied load and the modulus of elasticity, as well as under sleeper base vibroacceleration depending on time. The authors offer a systematic study on the basis of a mathematical model of the sources of noise in the process of a tram motion.

  4. Value for railway capacity

    DEFF Research Database (Denmark)

    Sameni, Melody Khadem; Preston, John M.

    2012-01-01

    to analyze the efficiency of operators in transforming inputs of allocated capacity of infrastructure and franchise payments into valuable passenger service outputs while avoiding delays. By addressing operational and economic aspects of capacity utilization simultaneously, the paper deviates from existing...... DEA work on the economic efficiency of railways by considering a new combination of input-output that also incorporates quality of service. The constant and variable returns to scale models are applied to the case study of franchised passenger operators in Great Britain. The follow-up Tobit regression...

  5. Case for railway electrification

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, A.N.

    1981-06-10

    The publication earlier this year of the joint BR-DTp final report of the review of main line electrification represented the culmination of over two years work; the study is almost certainly the most complex and comprehensive of this type ever undertaken. Heavy reliance on computer models allowed business analysis over the 34-year timespan of the review to extend to a level of detail that was not expected at the time of the last such investigation, the 1931 Weir Report of the Committee on Main Line Railway Electrification. It is encouraging that, despite the sweeping changes in both technology and economic conditions during the intervening years, the verdict remains highly favourable.

  6. Math anxiety: Brain cortical network changes in anticipation of doing mathematics.

    Science.gov (United States)

    Klados, Manousos A; Pandria, Niki; Micheloyannis, Sifis; Margulies, Daniel; Bamidis, Panagiotis D

    2017-12-01

    Following our previous work regarding the involvement of math anxiety (MA) in math-oriented tasks, this study tries to explore the differences in the cerebral networks' topology between self-reported low math-anxious (LMA) and high math-anxious (HMA) individuals, during the anticipation phase prior to a mathematical related experiment. For this reason, multichannel EEG recordings were adopted, while the solution of the inverse problem was applied in a generic head model, in order to obtain the cortical signals. The cortical networks have been computed for each band separately, using the magnitude square coherence metric. The main graph theoretical parameters, showed differences in segregation and integration in almost all EEG bands of the HMAs in comparison to LMAs, indicative of a great influence of the anticipatory anxiety prior to mathematical performance. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Prediction of paddy drying kinetics: A comparative study between mathematical and artificial neural network modelling

    Directory of Open Access Journals (Sweden)

    Beigi Mohsen

    2017-01-01

    Full Text Available The present study aimed at investigation of deep bed drying of rough rice kernels at various thin layers at different drying air temperatures and flow rates. A comparative study was performed between mathematical thin layer models and artificial neural networks to estimate the drying curves of rough rice. The suitability of nine mathematical models in simulating the drying kinetics was examined and the Midilli model was determined as the best approach for describing drying curves. Different feed forward-back propagation artificial neural networks were examined to predict the moisture content variations of the grains. The ANN with 4-18-18-1 topology, transfer function of hyperbolic tangent sigmoid and a Levenberg-Marquardt back propagation training algorithm provided the best results with the maximum correlation coefficient and the minimum mean square error values. Furthermore, it was revealed that ANN modeling had better performance in prediction of drying curves with lower root mean square error values.

  8. A mathematical framework for agent based models of complex biological networks.

    Science.gov (United States)

    Hinkelmann, Franziska; Murrugarra, David; Jarrah, Abdul Salam; Laubenbacher, Reinhard

    2011-07-01

    Agent-based modeling and simulation is a useful method to study biological phenomena in a wide range of fields, from molecular biology to ecology. Since there is currently no agreed-upon standard way to specify such models, it is not always easy to use published models. Also, since model descriptions are not usually given in mathematical terms, it is difficult to bring mathematical analysis tools to bear, so that models are typically studied through simulation. In order to address this issue, Grimm et al. proposed a protocol for model specification, the so-called ODD protocol, which provides a standard way to describe models. This paper proposes an addition to the ODD protocol which allows the description of an agent-based model as a dynamical system, which provides access to computational and theoretical tools for its analysis. The mathematical framework is that of algebraic models, that is, time-discrete dynamical systems with algebraic structure. It is shown by way of several examples how this mathematical specification can help with model analysis. This mathematical framework can also accommodate other model types such as Boolean networks and the more general logical models, as well as Petri nets.

  9. Estimating national exhaust emissions from railway vehicles in Turkey

    International Nuclear Information System (INIS)

    Dincer, Faruk; Elbir, Tolga

    2007-01-01

    The estimated exhaust emissions from railway vehicles in Turkey were presented. The emissions of nitrogen oxides (NO x ), hydrocarbon compounds (HC), carbon monoxide (CO), particulate matter (PM), sulfur dioxide (SO 2 ) and carbon dioxide (CO 2 ) from the diesel locomotives and railcars were calculated using the railway traffic data recorded by Turkish State Railways (TSR) for the period of 2000-2005. EPA emission factors were used for different vehicle types and operation modes such as shunting and line-hauling. Total emissions from railway vehicles in Turkey were estimated as 384 t y - 1 for HC, 1016 t y - 1 for CO, 6799 t y - 1 for NO X , 256 t y - 1 for PM, 357 t y - 1 for SO 2 and 383 537 t y - 1 for CO 2 for the year 2005. The distribution of emissions with respect to type of railway vehicles shows that the mainline locomotives contribute ∝ 91% to the total emissions. The increases of 22%, 39% and 49% in the current numbers of mainline locomotives, shunting locomotives and diesel railcars, respectively corresponding to the full capacity of railway network in Turkey will increase the annual emissions to 431 t y - 1 for HC, 1121 t y - 1 for CO, 7399 t y - 1 for NO X , 342 t y - 1 for PM, 552 t y - 1 for SO 2 and 420 256 t y - 1 for CO 2 . Total railway emissions constitute 0.15%, 0.08% and 4.21% of total Turkish traffic emissions for HC, CO and NO X , respectively. (author)

  10. Superconducting fault current limiter for railway transport

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, L. M., E-mail: LMFisher@niitfa.ru; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V. [National Technical Physics and Automation Research Institute (Russian Federation)

    2015-12-15

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with voltage of 3.5 kV and nominal current of 2 kA is developed. The SFCL consists of two series-connected units: block of superconducting modules and high-speed vacuum breaker with total disconnection time not more than 8 ms. The results of laboratory tests of superconducting SFCL modules in current limiting mode are presented. The recovery time of superconductivity is experimentally determined. The possibility of application of SFCL on traction substations of Russian Railways is considered.

  11. Superconducting fault current limiter for railway transport

    International Nuclear Information System (INIS)

    Fisher, L. M.; Alferov, D. F.; Akhmetgareev, M. R.; Budovskii, A. I.; Evsin, D. V.; Voloshin, I. F.; Kalinov, A. V.

    2015-01-01

    A resistive switching superconducting fault current limiter (SFCL) for DC networks with voltage of 3.5 kV and nominal current of 2 kA is developed. The SFCL consists of two series-connected units: block of superconducting modules and high-speed vacuum breaker with total disconnection time not more than 8 ms. The results of laboratory tests of superconducting SFCL modules in current limiting mode are presented. The recovery time of superconductivity is experimentally determined. The possibility of application of SFCL on traction substations of Russian Railways is considered

  12. Networking Theories on Giftedness--What We Can Learn from Synthesizing Renzulli's Domain General and Krutetskii's Mathematics-Specific Theory

    Science.gov (United States)

    Schindler, Maike; Rott, Benjamin

    2017-01-01

    Giftedness is an increasingly important research topic in educational sciences and mathematics education in particular. In this paper, we contribute to further theorizing mathematical giftedness through illustrating how networking processes can be conducted and illustrating their potential benefits. The paper focuses on two theories: Renzulli's…

  13. Railway noise annoyance on the railway track in northwest slovakia.

    Science.gov (United States)

    Pultznerova, Alzbeta; Eva, Panulinova; Kucharova, Daniela; Argalasova, Lubica

    2018-01-01

    This paper describes an assessment of noise caused by railway traffic in a large high-loaded railway track in Northwest Slovakia. 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. 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) (L Aeq  = 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 [OR MH  = 7.80 (4.02-15.14)] and the noise from industry [OR MH  = 3.08 (1.72-5.50)] in the exposed location. 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. 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.

  14. Do cities deserve more railway stations? The choice of a departure railway station in a multiple-station region

    NARCIS (Netherlands)

    Givoni, M.; Rietveld, P.

    2014-01-01

    Promoting the use of rail is an important element in sustainable transport policy. One of the most important decisions to make in planning the railway network is on the number of stations to provide. Stations are the access points to rail services and while each additional station increases rail's

  15. Environmental life cycle assessment of railway bridge materials using UHPFRC

    Directory of Open Access Journals (Sweden)

    Bizjak Karmen Fifer

    2016-10-01

    Full Text Available The railway infrastructure is a very important component of the world’s total transportation network. Investment in its construction and maintenance is significant on a global scale. Previously published life cycle assessment (LCA studies performed on road and rail systems very seldom included infrastructures in detail, mainly choosing to focus on vehicle manufacturing and fuel consumption. This article presents results from an environmental study for railway steel bridge materials for the demonstration case of the Buna Bridge in Croatia. The goal of these analyses was to compare two different types of remediation works for railway bridges with different materials and construction types. In the first part, the environmental impact of the classical concrete bridge construction was calculated, whereas in the second one, an alternative new solution, namely, the strengthening of the old steel bridge with ultra-high-performance fibre-reinforced concrete (UHPFRC deck, was studied. The results of the LCA show that the new solution with UHPFRC deck gives much better environmental performance. Up to now, results of LCA of railway open lines, railway bridges and tunnels have been published, but detailed analyses of the new solution with UHPFRC deck above the old bridge have not previously been performed.

  16. Environmental life cycle assessment of railway bridge materials using UHPFRC

    Science.gov (United States)

    Bizjak, Karmen Fifer; Šajna, Aljoša; Slanc, Katja; Knez, Friderik

    2016-10-01

    The railway infrastructure is a very important component of the world's total transportation network. Investment in its construction and maintenance is significant on a global scale. Previously published life cycle assessment (LCA) studies performed on road and rail systems very seldom included infrastructures in detail, mainly choosing to focus on vehicle manufacturing and fuel consumption. This article presents results from an environmental study for railway steel bridge materials for the demonstration case of the Buna Bridge in Croatia. The goal of these analyses was to compare two different types of remediation works for railway bridges with different materials and construction types. In the first part, the environmental impact of the classical concrete bridge construction was calculated, whereas in the second one, an alternative new solution, namely, the strengthening of the old steel bridge with ultra-high-performance fibre-reinforced concrete (UHPFRC) deck, was studied. The results of the LCA show that the new solution with UHPFRC deck gives much better environmental performance. Up to now, results of LCA of railway open lines, railway bridges and tunnels have been published, but detailed analyses of the new solution with UHPFRC deck above the old bridge have not previously been performed.

  17. Magnetically suspended railway

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, C

    1977-07-28

    The invention concerns the emergency support of a magnetically suspended railway. On failure of the magnetic suspension/tracking system, the vehicles touch down on the rail configuration by means of emergency gliding elements like sliding shoes, skids, or the like. In doing this, the touch-down shock of the emergency gliding elements has to be limited to a force maximum as small as possible. According to the invention a spring-attenuator combination is used for this purpose, the spring characteristic being linear while the attenuator has a square-law characteristic for the compressing and a linear characteristic for the yielding motion. The force maximum thus achieved is exactly half the size of the physically smallest possible force maximum for an emergency gliding element springed without damping.

  18. Estimating Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Jørgensen, Morten W.; Sorenson, Spencer C.

    1998-01-01

    Several parameters of importance for estimating emissions from railway traffic are discussed, and typical results presented. Typical emissions factors from diesel engines and electrical power generation are presented, and the effect of differences in national electrical generation sources...

  19. Future Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Sorenson, Spencer C.

    1998-01-01

    In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered. An estim......In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered...

  20. The dynamic behaviour of a railway mine vehicle

    Energy Technology Data Exchange (ETDEWEB)

    van Manen, P.; Brickle, B.V.

    1983-06-01

    The paper describes a mathematical model of a railway mine vehicle which is capable of predicting its dynamic behaviour in response to track inputs. The predictions of the model have been compared with the results of tests carried out on a new high speed mine vehicle and the correlation shown is good. The model yields frequency response information for the vehicle and may be used to simulate dynamic behaviour in response to track irregularities. (4 refs.)

  1. MATHEMATICAL MODELLING OF OPERATION HEAT NETWORKS IN VIEW OF HEAT LOSS

    Directory of Open Access Journals (Sweden)

    ZBARAZ L. I.

    2016-08-01

    Full Text Available Goal. In recent years, due to a significant rise in price of energy, the reduction of direct costs for heating becomes a priority. In the utilities especially important to optimization of energy heating system equipment. During transport of thermal energy in the distribution networks thermal losses occur along the length of the hydraulic pipes and the coolant pumping losses. These loss-dependence of the particular distribution network. Changing temperature and the hydraulic regime at the source necessary to achieve the minimum cost of transport for today acting tariffs for energy. Scientific novelty. The studies received law changes head to the source at the qualitative and quantitative methods of regulation. Results. A mathematical model of an extensive network of decentralized heat source heating, which are analyzed using different methods of regulating and found the best.

  2. Mathematics anxiety reduces default mode network deactivation in response to numerical tasks

    Directory of Open Access Journals (Sweden)

    Belinda ePletzer

    2015-04-01

    Full Text Available Mathematics anxiety is negatively related to mathematics performance, thereby threatening the professional success. Preoccupation with the emotional content of the stimuli may consume working memory resources, which may be reflected in decreased deactivation of areas associated with the default mode network (DMN activated during self-referential and emotional processing. The common problem is that math anxiety is usually associated with poor math performance, so that any group differences are difficult to interpret.Here we compared the BOLD-response of 18 participants with high (HMAs and 18 participants with low mathematics anxiety (LMAs matched for their mathematical performance to two numerical tasks (number comparison, number bisection. During both tasks, we found stronger deactivation within the DMN in LMAs compared to HMAs, while BOLD-response in task-related activation areas did not differ between HMAs and LMAs. The difference in DMN deactivation between the HMA and LMA group was more pronounced in stimuli with additional requirement on inhibitory functions, but did not differ between number magnitude processing and arithmetic fact retrieval.

  3. Mathematics anxiety reduces default mode network deactivation in response to numerical tasks.

    Science.gov (United States)

    Pletzer, Belinda; Kronbichler, Martin; Nuerk, Hans-Christoph; Kerschbaum, Hubert H

    2015-01-01

    Mathematics anxiety is negatively related to mathematics performance, thereby threatening the professional success. Preoccupation with the emotional content of the stimuli may consume working memory resources, which may be reflected in decreased deactivation of areas associated with the default mode network (DMN) activated during self-referential and emotional processing. The common problem is that math anxiety is usually associated with poor math performance, so that any group differences are difficult to interpret. Here we compared the BOLD-response of 18 participants with high (HMAs) and 18 participants with low mathematics anxiety (LMAs) matched for their mathematical performance to two numerical tasks (number comparison, number bisection). During both tasks, we found stronger deactivation within the DMN in LMAs compared to HMAs, while BOLD-response in task-related activation areas did not differ between HMAs and LMAs. The difference in DMN deactivation between the HMA and LMA group was more pronounced in stimuli with additional requirement on inhibitory functions, but did not differ between number magnitude processing and arithmetic fact retrieval.

  4. Novel Strategy for Discrimination of Transcription Factor Binding Motifs Employing Mathematical Neural Network

    Science.gov (United States)

    Sugimoto, Asuka; Sumi, Takuya; Kang, Jiyoung; Tateno, Masaru

    2017-07-01

    Recognition in biological macromolecular systems, such as DNA-protein recognition, is one of the most crucial problems to solve toward understanding the fundamental mechanisms of various biological processes. Since specific base sequences of genome DNA are discriminated by proteins, such as transcription factors (TFs), finding TF binding motifs (TFBMs) in whole genome DNA sequences is currently a central issue in interdisciplinary biophysical and information sciences. In the present study, a novel strategy to create a discriminant function for discrimination of TFBMs by constituting mathematical neural networks (NNs) is proposed, together with a method to determine the boundary of signals (TFBMs) and noise in the NN-score (output) space. This analysis also leads to the mathematical limitation of discrimination in the recognition of features representing TFBMs, in an information geometrical manifold. Thus, the present strategy enables the identification of the whole space of TFBMs, right up to the noise boundary.

  5. Prediction of Prospective Mathematics Teachers' Academic Success in Entering Graduate Education by Using Back-Propagation Neural Network

    Science.gov (United States)

    Bahadir, Elif

    2016-01-01

    The purpose of this study is to examine a neural network based approach to predict achievement in graduate education for Elementary Mathematics prospective teachers. With the help of this study, it can be possible to make an effective prediction regarding the students' achievement in graduate education with Artificial Neural Networks (ANN). Two…

  6. An overview of natural hazard impacts to railways and urban transportation systems

    Science.gov (United States)

    Bíl, Michal; Nezval, Vojtěch; Bílová, Martina; Andrášik, Richard; Kubeček, Jan

    2017-04-01

    We present an overview and two case studies of natural hazard impacts on rail transportation systems in the Czech Republic. Flooding, landsliding, heavy snowfall, windstorms and glaze (black ice) are the most common natural processes which occur in this region. Whereas flooding and landsliding usually cause direct damage to the transportation infrastructure, other hazards predominantly cause indirect losses. Railway and urban tramline networks are almost fully dependent on electricity which is provided by a system of overhead lines (electric lines above the tracks). These lines are extremely susceptible to formation of glaze which blocks conduction of electric current. A December 2014 glaze event caused significant indirect losses in the largest Czech cities and railways due to the above-mentioned process. Details of this event will be provided during the presentation. Windstorms usually cause tree falls which can affect overhead lines and physically block railway tracks. Approximately 30 % of the Czech railway network is closer than 50 m from the nearest forest. This presents significant potential for transport interruption due to falling trees. Complicated legal relations among the owners of the plots of land along railways, the environment (full-grown trees and related habitat), and the railway administrator are behind many traffic interruptions due to falling trees. We have registered 2040 tree falls between 2012 and 2015 on the railway network. A model of the fallen tree hazard was created for the entire Czech railway network. Both above-mentioned case studies provide illustrative examples of the increased fragility of the modern transportation systems which fully rely on electricity. Natural processes with a low destructive power are thereby able to cause network wide service cut-offs.

  7. Sweden goes in for railways - an example to Norway

    International Nuclear Information System (INIS)

    Killingland, Tore

    2004-01-01

    It is a sad fact that in their 150th anniversary, with very few exceptions, the Norwegian railways still use the first generation network, which dates back to the late 1800s. Off course, this puts the train at a serious disadvantage in the competition with cars and buses, which run on a third or four generation network of roads. The Norwegian Parliament has cut down on the fuel tax for the road traffic. They might have used this tax to provide much more environmentally friendly transport facilities. Green taxes are a proper means of adapting society to a sustainable way of using energy. The article contrasts the Norwegian policy with the Swedish one. The Swedes are preparing to invest twice as much in railways as in roads for the period of 2004 - 2015, while in Norway three times as much money will be spent on roads as on railways. Politicians in Norway essentially agree to concentrate on the railway, but they do not do it. Conservationists expect a clear change of course in the communications policy, with Sweden as a model

  8. Opportunity to Save Historical Railway Infrastructure - Adaptation and Functional Conversion of Facilities

    Science.gov (United States)

    Podwojewska, Magdalena

    2017-10-01

    After years of neglect and underinvestment, the Polish railways are now witnessing a rapid modernization of both their technical facilities and rolling stock. However, this is true only of the main railway lines connecting major urban complexes. It is worth pointing out that a great number of secondary lines, railway stations and halts still has not been covered by the transformation process. Railway facilities, warehouses and service features are in decay. Rapid technological developments have caused numerous architectural structures of historical interest and service features to fall out of use. There are historical railway facilities dating back to the late 19th or early 20th centuries, whose condition is constantly deteriorating. The only way to save these structures is to change the manner, in which they are being used, and attract new investors and operators. The adaptation of buildings may be carried out in a number of ways by following different strategies. The process depends on the structure’s current condition and significance for the railway network. The facilities which are disused as a result of technological changes in the rolling stock and infrastructure include workshops, steam locomotive bays, turntables and warehouses. Their size and location within a city make them a perfect place for commercial services, exhibitions, heritage sites, concerts and other events attracting great numbers of people. Other strategies may be used for constructions located next to railways lines, whose role has declined. Such constructions include small railway stations, warehouses, reloading and forwarding facilities, railway ramps, railway staff buildings as well as residences for railway employees. Railway stations located at large junctions can handle passenger traffic or freight loading operations. As well as acting as the only window to the world, railway stations in small towns housed all the services available in the place. At the same time, they served as

  9. Magnetic levitation railways. 2. enlarged ed. Magnetschwebebahnen

    Energy Technology Data Exchange (ETDEWEB)

    Miedtank, R [comp.

    1989-01-01

    The bibliography contains 129 literature references, mostly with German abstracts on: Representation of the magnetic levitation railway (MAGLEV railway) as a fast modern railway; type of design of tracks and stations; manufacture of track supports made of steel and reinforced concrete with the accuracy required for this fast railway system. Introduction of experimental sections and planning study for this means of transport. (orig./HP).

  10. Experimental Stress Analysis at Railway Inspection Pit

    Directory of Open Access Journals (Sweden)

    Nicuşor Laurentiu Zaharia

    2008-10-01

    Full Text Available Railway inspection pits are used in railway halls. The purpose of inspection pits is to allow the working under the vehicle. Inspection pits can be found in locomotive depots, factories etc. The new design for a inspection pit in a railway hall involve tests in purpose of homologations the railway infrastructure. Before the homologation committee meeting, tests are made; after the test, a testing report is made which it will be part at homologation documents.

  11. An approach for optimally extending mathematical models of signaling networks using omics data.

    Science.gov (United States)

    Bianconi, Fortunato; Patiti, Federico; Baldelli, Elisa; Crino, Lucio; Valigi, Paolo

    2015-01-01

    Mathematical modeling is a key process in Systems Biology and the use of computational tools such as Cytoscape for omics data processing, need to be integrated in the modeling activity. In this paper we propose a new methodology for modeling signaling networks by combining ordinary differential equation models and a gene recommender system, GeneMANIA. We started from existing models, that are stored in the BioModels database, and we generated a query to use as input for the GeneMANIA algorithm. The output of the recommender system was then led back to the kinetic reactions that were finally added to the starting model. We applied the proposed methodology to EGFR-IGF1R signal transduction network, which plays an important role in translational oncology and cancer therapy of non small cell lung cancer.

  12. EpiModel: An R Package for Mathematical Modeling of Infectious Disease over Networks.

    Science.gov (United States)

    Jenness, Samuel M; Goodreau, Steven M; Morris, Martina

    2018-04-01

    Package EpiModel provides tools for building, simulating, and analyzing mathematical models for the population dynamics of infectious disease transmission in R. Several classes of models are included, but the unique contribution of this software package is a general stochastic framework for modeling the spread of epidemics on networks. EpiModel integrates recent advances in statistical methods for network analysis (temporal exponential random graph models) that allow the epidemic modeling to be grounded in empirical data on contacts that can spread infection. This article provides an overview of both the modeling tools built into EpiModel , designed to facilitate learning for students new to modeling, and the application programming interface for extending package EpiModel , designed to facilitate the exploration of novel research questions for advanced modelers.

  13. RESTRUCTURING INDONESIAN RAILWAY – INTEGRATION OR SEPARATION

    Directory of Open Access Journals (Sweden)

    Utut Widyanto

    2013-05-01

    The study found that the separation model is still the best approach for restructuring Indonesian railway but if looking at the Indonesian railway current condition with its problem of backlog assets it would be better that the separation approach is used in the development of railway in other islands. Keywords: Restructuration, separation, funds, operator.

  14. Well test mathematical model for fractures network in tight oil reservoirs

    Science.gov (United States)

    Diwu, Pengxiang; Liu, Tongjing; Jiang, Baoyi; Wang, Rui; Yang, Peidie; Yang, Jiping; Wang, Zhaoming

    2018-02-01

    Well test, especially build-up test, has been applied widely in the development of tight oil reservoirs, since it is the only available low cost way to directly quantify flow ability and formation heterogeneity parameters. However, because of the fractures network near wellbore, generated from artificial fracturing linking up natural factures, traditional infinite and finite conductivity fracture models usually result in significantly deviation in field application. In this work, considering the random distribution of natural fractures, physical model of fractures network is proposed, and it shows a composite model feature in the large scale. Consequently, a nonhomogeneous composite mathematical model is established with threshold pressure gradient. To solve this model semi-analytically, we proposed a solution approach including Laplace transform and virtual argument Bessel function, and this method is verified by comparing with existing analytical solution. The matching data of typical type curves generated from semi-analytical solution indicates that the proposed physical and mathematical model can describe the type curves characteristic in typical tight oil reservoirs, which have up warping in late-term rather than parallel lines with slope 1/2 or 1/4. It means the composite model could be used into pressure interpretation of artificial fracturing wells in tight oil reservoir.

  15. Optimal Train Dispatching at Railway Stations : A Discrete Event Dynamic System Approach

    NARCIS (Netherlands)

    Goverde, R.M.P.

    1999-01-01

    Reliability of transfers in a transportation network largely influences the level of service of trip chains. Especially in low-frequency service networks like (long-distance) railway networks. Running and dwell times are typically subject to random variations resulting in arrival delays during

  16. Mathematical model on malicious attacks in a mobile wireless network with clustering

    International Nuclear Information System (INIS)

    Haldar, Kaushik; Mishra, Bimal Kumar

    2015-01-01

    A mathematical model has been formulated for the analysis of a wireless epidemic on a clustered heterogeneous network. The model introduces mobility into the epidemic framework assuming that the component nodes have a tendency to be attached with a frequently visited home cluster. This underlines the inherent regularity in the mobility pattern of mobile nodes in a wireless network. The analysis focuses primarily on features that arise because of the mobility considerations compared in the larger scenario formed by the epidemic aspects. A result on the invariance of the home cluster populations with respect to time provides an important view-point of the long-term behavior of the system. The analysis also focuses on obtaining a basic threshold condition that guides the epidemic behavior of the system. Analytical as well as numerical results have also been obtained to establish the asymptotic behavior of the connected components of the network, and that of the whole network when the underlying graph turns out to be irreducible. Applications to proximity based attacks and to scenarios with high cluster density have also been outlined

  17. A mathematical framework for modelling and evaluating natural gas pipeline networks under hydrogen injection

    Energy Technology Data Exchange (ETDEWEB)

    Tabkhi, F.; Azzaro-Pantel, C.; Pibouleau, L.; Domenech, S. [Laboratoire de Genie Chimique, UMR5503 CNRS/INP/UPS, 5 rue Paulin Talabot F-BP1301, 31106 Toulouse Cedex 1 (France)

    2008-11-15

    This article presents the framework of a mathematical formulation for modelling and evaluating natural gas pipeline networks under hydrogen injection. The model development is based on gas transport through pipelines and compressors which compensate for the pressure drops by implying mainly the mass and energy balances on the basic elements of the network. The model was initially implemented for natural gas transport and the principle of extension for hydrogen-natural gas mixtures is presented. The objective is the treatment of the classical fuel minimizing problem in compressor stations. The optimization procedure has been formulated by means of a nonlinear technique within the General Algebraic Modelling System (GAMS) environment. This work deals with the adaptation of the current transmission networks of natural gas to the transport of hydrogen-natural gas mixtures. More precisely, the quantitative amount of hydrogen that can be added to natural gas can be determined. The studied pipeline network, initially proposed in [1] is revisited here for the case of hydrogen-natural gas mixtures. Typical quantitative results are presented, showing that the addition of hydrogen to natural gas decreases significantly the transmitted power: the maximum fraction of hydrogen that can be added to natural gas is around 6 mass% for this example. (author)

  18. Acoustic energy propagation around railways

    Science.gov (United States)

    Cizkova, Petra

    2017-09-01

    The article deals with the issues of acoustic energy propagation around railways. The research subject was noise emission spreading into the surroundings during the passage of trains over a directly travelled steel bridge construction. Noise emissions were measured using direct measurements in the field. The measurements were performed in two measurement profiles. The noise exposures A LAE measured near the steel bridge construction were compared against the noise exposures A LAE captured on an open track. From the difference of these data, the noise level of the steel bridge structure was determined. Part of the research was to evaluate the effect of the reconstruction of the railway track superstructure on the acoustic situation in the given section of the railway track. The article describes the methodology of measurements, including the processing and evaluation of measured data. The article points out the noise levels of the steel bridge construction and assesses changes in the acoustic situation after the reconstruction.

  19. Teacher Formation in the Mathematical Thinking through Problem Solving in the Second Phase of the CCyM Network of Reading Comprehension and Mathematics

    Directory of Open Access Journals (Sweden)

    LUZ STELLA LÓPEZ

    2008-12-01

    Full Text Available This article shares the design, implementation, and evaluation of theLesson Study process used for the professional development of teachers of mathematics, through the Red de Comprensión Lectora y Matemáticas – CCyM Network, in ways to teach mathematics through problem solving. The program began with a course on the implementation of the Thinking Classroom, followed by the semi-presencial Lesson Study process. An analysis of teacher interactions during the Lesson Study process yielded these categories of study: Group Collective Thinking, Mathematical Pedagogical Content Knowledge, Subject Matter Knowledge, Knowledge about Technology, and Expert Support. The analysis reflected variations in group interactions, in the command of concepts, in reflective practice, in the ability to make arguments and to propose changes in practice, and in the ability to self-regulate.

  20. Robustness and Optimization of Complex Networks : Reconstructability, Algorithms and Modeling

    NARCIS (Netherlands)

    Liu, D.

    2013-01-01

    The infrastructure networks, including the Internet, telecommunication networks, electrical power grids, transportation networks (road, railway, waterway, and airway networks), gas networks and water networks, are becoming more and more complex. The complex infrastructure networks are crucial to our

  1. Towards the Internet of Smart Trains: A Review on Industrial IoT-Connected Railways.

    Science.gov (United States)

    Fraga-Lamas, Paula; Fernández-Caramés, Tiago M; Castedo, Luis

    2017-06-21

    Nowadays, the railway industry is in a position where it is able to exploit the opportunities created by the IIoT (Industrial Internet of Things) and enabling communication technologies under the paradigm of Internet of Trains. This review details the evolution of communication technologies since the deployment of GSM-R, describing the main alternatives and how railway requirements, specifications and recommendations have evolved over time. The advantages of the latest generation of broadband communication systems (e.g., LTE, 5G, IEEE 802.11ad) and the emergence of Wireless Sensor Networks (WSNs) for the railway environment are also explained together with the strategic roadmap to ensure a smooth migration from GSM-R. Furthermore, this survey focuses on providing a holistic approach, identifying scenarios and architectures where railways could leverage better commercial IIoT capabilities. After reviewing the main industrial developments, short and medium-term IIoT-enabled services for smart railways are evaluated. Then, it is analyzed the latest research on predictive maintenance, smart infrastructure, advanced monitoring of assets, video surveillance systems, railway operations, Passenger and Freight Information Systems (PIS/FIS), train control systems, safety assurance, signaling systems, cyber security and energy efficiency. Overall, it can be stated that the aim of this article is to provide a detailed examination of the state-of-the-art of different technologies and services that will revolutionize the railway industry and will allow for confronting today challenges.

  2. Towards the Internet of Smart Trains: A Review on Industrial IoT-Connected Railways

    Science.gov (United States)

    Fraga-Lamas, Paula; Fernández-Caramés, Tiago M.; Castedo, Luis

    2017-01-01

    Nowadays, the railway industry is in a position where it is able to exploit the opportunities created by the IIoT (Industrial Internet of Things) and enabling communication technologies under the paradigm of Internet of Trains. This review details the evolution of communication technologies since the deployment of GSM-R, describing the main alternatives and how railway requirements, specifications and recommendations have evolved over time. The advantages of the latest generation of broadband communication systems (e.g., LTE, 5G, IEEE 802.11ad) and the emergence of Wireless Sensor Networks (WSNs) for the railway environment are also explained together with the strategic roadmap to ensure a smooth migration from GSM-R. Furthermore, this survey focuses on providing a holistic approach, identifying scenarios and architectures where railways could leverage better commercial IIoT capabilities. After reviewing the main industrial developments, short and medium-term IIoT-enabled services for smart railways are evaluated. Then, it is analyzed the latest research on predictive maintenance, smart infrastructure, advanced monitoring of assets, video surveillance systems, railway operations, Passenger and Freight Information Systems (PIS/FIS), train control systems, safety assurance, signaling systems, cyber security and energy efficiency. Overall, it can be stated that the aim of this article is to provide a detailed examination of the state-of-the-art of different technologies and services that will revolutionize the railway industry and will allow for confronting today challenges. PMID:28635672

  3. Modern techniques for condition monitoring of railway vehicle dynamics

    International Nuclear Information System (INIS)

    Ngigi, R W; Pislaru, C; Ball, A; Gu, F

    2012-01-01

    A modern railway system relies on sophisticated monitoring systems for maintenance and renewal activities. Some of the existing conditions monitoring techniques perform fault detection using advanced filtering, system identification and signal analysis methods. These theoretical approaches do not require complex mathematical models of the system and can overcome potential difficulties associated with nonlinearities and parameter variations in the system. Practical applications of condition monitoring tools use sensors which are mounted either on the track or rolling stock. For instance, monitoring wheelset dynamics could be done through the use of track-mounted sensors, while vehicle-based sensors are preferred for monitoring the train infrastructure. This paper attempts to collate and critically appraise the modern techniques used for condition monitoring of railway vehicle dynamics by analysing the advantages and shortcomings of these methods.

  4. DETERMINATION OF THE OPTIMAL CAPITAL INVESTMENTS TO ENSURE THE SUSTAINABLE DEVELOPMENT OF THE RAILWAY

    Directory of Open Access Journals (Sweden)

    O. I. Kharchenko

    2015-04-01

    Full Text Available Purpose. Every year more attention is paid for the theoretical and practical issue of sustainable development of railway transport. But today the mechanisms of financial support of this development are poorly understood. Therefore, the aim of this article is to determine the optimal investment allocation to ensure sustainable development of the railway transport on the example of State Enterprise «Prydniprovsk Railway» and the creation of preconditions for the mathematical model development. Methodology. The ensuring task for sustainable development of railway transport is solved on the basis of the integral indicator of sustainable development effectiveness and defined as the maximization of this criterion. The optimization of measures technological and technical characters are proposed to carry out for increasing values of the integral performance measure components. To the optimization activities of technological nature that enhance the performance criteria belongs: optimization of the number of train and shunting locomotives, optimization of power handling mechanisms at the stations, optimization of routes of train flows. The activities related to the technical nature include: modernization of railways in the direction of their electrification and modernization of the running gear and coupler drawbars of rolling stock, as well as means of separators mechanization at stations to reduce noise impacts on the environment. Findings. The work resulted in the optimal allocation of investments to ensure the sustainable development of railway transportation of State Enterprise «Prydniprovsk Railway». This allows providing such kind of railway development when functioning of State Enterprise «Prydniprovsk Railway» is characterized by a maximum value of the integral indicator of efficiency. Originality. The work was reviewed and the new approach was proposed to determine the optimal allocation of capital investments to ensure sustainable

  5. PERSPECTIVES OF UKRAINIAN RAILWAY TOURISM DEVELOPMENT ON NARROW-GAUGE LINES OF ZAKARPATTIA

    Directory of Open Access Journals (Sweden)

    V. G. Kuznetsov

    2015-07-01

    Full Text Available Purpose.The purpose of the paper is: (1 the definition of perspectives development of Ukrainian railway tourism on the narrow gauge lines of Zakarpattia; 2 technical condition analysis of Borzhava narrow gauge railway for the project to restore the effective functioning of mountain railways track, width 750 mm in the Carpathian region, with the possibility of their accession to the distributed travel network; 3 the study of the modern state and tendencies of development of tourist industry of Ukraine and the passenger economy of national railways; 4 clarification of the role and place of the railway tourism in the transportation system. Methodology. The expert group has carried out field inspections and field investigations of facilities track facilities and passenger infrastructure, rolling stock and ancillary industries involved in the functioning narrow-gauge railway. It was estimated the overall technical condition of the railway track and engineering structures section of narrow-gauge Railways in the Carpathian region. Findings. In the framework of on-site examinations of the expert group found that the objects of tracks, passenger and freight infrastructure, rolling stock and ancillary industries involved in the operation of narrow-gauge Railways are in poor condition and require significant updates and major repairs. But the routes of passenger trains remain fit for participation in the project of development of railway tourism of Ukraine Originality. For the first time the state of the narrow-gauge railway for further implementation of the project on the development of rail tourism in Ukraine was realized. The analysis of foreign experience of organization of railway tourism has been carried out. The modern state and tendencies of development of tourist industry of Ukraine was studied, the factors of competitiveness of rail transport for providing tourist transport in Ukraine were identified and systematized.Practical value. The recovery

  6. A mathematical model for generating bipartite graphs and its application to protein networks

    Science.gov (United States)

    Nacher, J. C.; Ochiai, T.; Hayashida, M.; Akutsu, T.

    2009-12-01

    Complex systems arise in many different contexts from large communication systems and transportation infrastructures to molecular biology. Most of these systems can be organized into networks composed of nodes and interacting edges. Here, we present a theoretical model that constructs bipartite networks with the particular feature that the degree distribution can be tuned depending on the probability rate of fundamental processes. We then use this model to investigate protein-domain networks. A protein can be composed of up to hundreds of domains. Each domain represents a conserved sequence segment with specific functional tasks. We analyze the distribution of domains in Homo sapiens and Arabidopsis thaliana organisms and the statistical analysis shows that while (a) the number of domain types shared by k proteins exhibits a power-law distribution, (b) the number of proteins composed of k types of domains decays as an exponential distribution. The proposed mathematical model generates bipartite graphs and predicts the emergence of this mixing of (a) power-law and (b) exponential distributions. Our theoretical and computational results show that this model requires (1) growth process and (2) copy mechanism.

  7. A mathematical model for generating bipartite graphs and its application to protein networks

    Energy Technology Data Exchange (ETDEWEB)

    Nacher, J C [Department of Complex Systems, Future University-Hakodate (Japan); Ochiai, T [Faculty of Engineering, Toyama Prefectural University (Japan); Hayashida, M; Akutsu, T [Bioinformatics Center, Institute for Chemical Research, Kyoto University (Japan)

    2009-12-04

    Complex systems arise in many different contexts from large communication systems and transportation infrastructures to molecular biology. Most of these systems can be organized into networks composed of nodes and interacting edges. Here, we present a theoretical model that constructs bipartite networks with the particular feature that the degree distribution can be tuned depending on the probability rate of fundamental processes. We then use this model to investigate protein-domain networks. A protein can be composed of up to hundreds of domains. Each domain represents a conserved sequence segment with specific functional tasks. We analyze the distribution of domains in Homo sapiens and Arabidopsis thaliana organisms and the statistical analysis shows that while (a) the number of domain types shared by k proteins exhibits a power-law distribution, (b) the number of proteins composed of k types of domains decays as an exponential distribution. The proposed mathematical model generates bipartite graphs and predicts the emergence of this mixing of (a) power-law and (b) exponential distributions. Our theoretical and computational results show that this model requires (1) growth process and (2) copy mechanism.

  8. Equilibrium switching and mathematical properties of nonlinear interaction networks with concurrent antagonism and self-stimulation

    International Nuclear Information System (INIS)

    Rabajante, Jomar Fajardo; Talaue, Cherryl Ortega

    2015-01-01

    Graphical abstract: Display Omitted -- Highlights: •Properties of n-dimensional decision model of competitive interaction networks. •Graphical technique for component-wise and steady state stability analysis. •Search for parameter conditions that control equilibrium switching. •Illustrations of multi-stable systems and repressilators. -- Abstract: Concurrent decision-making model (CDM) of interaction networks with more than two antagonistic components represents various biological systems, such as gene interaction, species competition and mental cognition. The CDM model assumes sigmoid kinetics where every component stimulates itself but concurrently represses the others. Here we prove generic mathematical properties (e.g., location and stability of steady states) of n-dimensional CDM with either symmetric or asymmetric reciprocal antagonism between components. Significant modifications in parameter values serve as biological regulators for inducing steady state switching by driving a temporal state to escape an undesirable equilibrium. Increasing the maximal growth rate and decreasing the decay rate can expand the basin of attraction of a steady state that contains the desired dominant component. Perpetually adding an external stimulus could shut down multi-stability of the system which increases the robustness of the system against stochastic noise. We further show that asymmetric interaction forming a repressilator-type network generates oscillatory behavior

  9. A mathematical model for generating bipartite graphs and its application to protein networks

    International Nuclear Information System (INIS)

    Nacher, J C; Ochiai, T; Hayashida, M; Akutsu, T

    2009-01-01

    Complex systems arise in many different contexts from large communication systems and transportation infrastructures to molecular biology. Most of these systems can be organized into networks composed of nodes and interacting edges. Here, we present a theoretical model that constructs bipartite networks with the particular feature that the degree distribution can be tuned depending on the probability rate of fundamental processes. We then use this model to investigate protein-domain networks. A protein can be composed of up to hundreds of domains. Each domain represents a conserved sequence segment with specific functional tasks. We analyze the distribution of domains in Homo sapiens and Arabidopsis thaliana organisms and the statistical analysis shows that while (a) the number of domain types shared by k proteins exhibits a power-law distribution, (b) the number of proteins composed of k types of domains decays as an exponential distribution. The proposed mathematical model generates bipartite graphs and predicts the emergence of this mixing of (a) power-law and (b) exponential distributions. Our theoretical and computational results show that this model requires (1) growth process and (2) copy mechanism.

  10. A new fuzzy mathematical model for green supply chain network design

    Directory of Open Access Journals (Sweden)

    Mohsen Sadegh Amalnick

    2017-01-01

    Full Text Available The environmental changes caused by industrial activities have spurred a significant interest in designing supply chain networks by considering environmental issues such as CO2 emission. The pivotal role of taking uncertainty and risk into account in closed-loop supply chain networks has induced numerous researchers and practitioners to develop appropriate decision making tools to cope with these issues in such networks. To design a supply chain regarding environmental impacts under uncertainty of the input data and to cope with the operational risks, this paper proposes a multi objective possibilistic optimization model. The proposed model minimizes traditional costs such as cost of products shipment, purchasing machines and so on, as well as minimizing the environmental impact, and as a results strikes a balance between the two objective functions. Furthermore, in order to solve the proposed multi objective fuzzy mathematical programming model, an interactive fuzzy solution approach is applied. Numerical experiments are used to prove the applicability and feasibility of the developed possibilistic programming model and the usefulness of the applied hybrid solution approach.

  11. Waiting experience in railway environments

    NARCIS (Netherlands)

    van Hagen, M.; Galetzka, Mirjam; Pruyn, Adriaan T.H.

    2014-01-01

    At railway stations, waiting time is usually an unavoidable aspect of the journey for train passengers. According to the attentional model of time, pleasant surroundings and other forms of distraction reduce perceived waiting time. Not every individual reacts identically in the same surroundings.

  12. The Use of Energy Storage Systems for Supporting the Voltage Needs of Urban and Suburban Railway Contact Lines

    Directory of Open Access Journals (Sweden)

    Enrico Pagano

    2013-03-01

    Full Text Available The paper aims to contribute to the use of electric double layer capacitor (EDLC sets for boosting voltages of contact lines in urban and suburban railway traction systems. Different electrical configurations of contact lines are considered and investigated. For each of them, proper mathematical models are suggested to evaluate the electrical performances of the contact lines. They give rise, also, to sample design procedures for the sizing of the most appropriate energy storage systems, to be distributed along the lines, for boosting line voltages and avoiding undesired voltage drops. A numerical example based on the “Cumana” suburban Naples railway network is presented to give an idea of the weights and sizes of electric double layer capacitors needed to boost the voltage of a sample contact line. In particular, three different EDLC systems, for a overall installed energy of 9.6 kWh, have been placed nearby the stations presenting the highest voltage drops during the most representative situation of trains’ service. The new voltage drop is equal to 32% of that obtained in absence of EDLCs.

  13. The Use of Energy Storage Systems for Supporting the Voltage Needs of Urban and Suburban Railway Contact Lines

    Energy Technology Data Exchange (ETDEWEB)

    Iannuzzi, Diago [University of Federico II, Naples (Italy). Electrical Engineering Department; Pagano, Enrico [University of Federico II, Naples (Italy). Electrical Engineering Department; Tricoli, Pietro [University of Birmingham (United Kingdom). School of Electronic, Electrical and Computer Engineering

    2013-04-15

    The paper aims to contribute to the use of electric double layer capacitor (EDLC) sets for boosting voltages of contact lines in urban and suburban railway traction systems. Different electrical configurations of contact lines are considered and investigated. For each of them, proper mathematical models are suggested to evaluate the electrical performances of the contact lines. They give rise, also, to sample design procedures for the sizing of the most appropriate energy storage systems, to be distributed along the lines, for boosting line voltages and avoiding undesired voltage drops. A numerical example based on the “Cumana” suburban Naples railway network is presented to give an idea of the weights and sizes of electric double layer capacitors needed to boost the voltage of a sample contact line. In particular, three different EDLC systems, for a overall installed energy of 9.6 kWh, have been placed nearby the stations presenting the highest voltage drops during the most representative situation of trains’ service. The new voltage drop is equal to 32% of that obtained in absence of EDLCs.

  14. A review of mathematical models for the formation of vascular networks

    KAUST Repository

    Scianna, M.

    2013-09-01

    Two major mechanisms are involved in the formation of blood vasculature: vasculogenesis and angiogenesis. The former term describes the formation of a capillary-like network from either a dispersed or a monolayered population of endothelial cells, reproducible also in vitro by specific experimental assays. The latter term describes the sprouting of new vessels from an existing capillary or post-capillary venule. Similar mechanisms are also involved in the formation of the lymphatic system through a process generally called lymphangiogenesis. A number of mathematical approaches have been used to analyze these phenomena. In this paper, we review the different types of models, with special emphasis on their ability to reproduce different biological systems and to predict measurable quantities which describe the overall processes. Finally, we highlight the advantages specific to each of the different modelling approaches. © 2013 Elsevier Ltd.

  15. Building a Network to Support Girls and Women in Science, Technology, Engineering, and Mathematics

    Science.gov (United States)

    Spears, Jacqueline D.; Dyer, Ruth A.; Franks, Suzanne E.; Montelone, Beth A.

    Women today constitute over half of the U.S. population and almost half of its overall workforce, yet they make up less than a quarter of the science and engineering workforce. Many historical and social factors contribute to this discrepancy, and numerous individual, institutional, and governmental attempts have been made to redress it. However, many of the efforts to promote, include, and engage girls and women in science, technology, engineering, and mathematics (STEM) education and professions have been made in isolation. At Kansas State University, the authors have begun a systemic effort to increase the participation of girls and women in STEM. This article describes the creation and initial activities of a network of partners that includes universities, school districts, corporations, governmental agencies, and nonprofit organizations, assembled under the aegis of a project supported by funding from the National Science Foundation.

  16. Fuzzy logic, artificial neural network and mathematical model for prediction of white mulberry drying kinetics

    Science.gov (United States)

    Jahedi Rad, Shahpour; Kaveh, Mohammad; Sharabiani, Vali Rasooli; Taghinezhad, Ebrahim

    2018-05-01

    The thin-layer convective- infrared drying behavior of white mulberry was experimentally studied at infrared power levels of 500, 1000 and 1500 W, drying air temperatures of 40, 55 and 70 °C and inlet drying air speeds of 0.4, 1 and 1.6 m/s. Drying rate raised with the rise of infrared power levels at a distinct air temperature and velocity and thus decreased the drying time. Five mathematical models describing thin-layer drying have been fitted to the drying data. Midlli et al. model could satisfactorily describe the convective-infrared drying of white mulberry fruit with the values of the correlation coefficient (R 2=0.9986) and root mean square error of (RMSE= 0.04795). Artificial neural network (ANN) and fuzzy logic methods was desirably utilized for modeling output parameters (moisture ratio (MR)) regarding input parameters. Results showed that output parameters were more accurately predicted by fuzzy model than by the ANN and mathematical models. Correlation coefficient (R 2) and RMSE generated by the fuzzy model (respectively 0.9996 and 0.01095) were higher than referred values for the ANN model (0.9990 and 0.01988 respectively).

  17. The flywheel as an energy storage device in railway and tram networks; Schwungrad als Energiespeicher in Bahnnetzen. Erfahrungen aus einem Versuchsprojekt in der Stadt Zuerich

    Energy Technology Data Exchange (ETDEWEB)

    Bischof, M. [EWZ, Zuerich (Switzerland)

    2010-07-01

    This article reviews experience made with a flywheel-based energy storage system that was tested on part of Zurich's tram network. The aim of the six weeks of tests was to determine how much energy that is generated by the recuperation of braking energy can be temporarily stored to provide power for accelerating trams on the network. The article discusses the valuable knowledge gained during the tests. The basic ideas behind the tests and the goals aimed for are discussed, both concerning energy balances as well as other factors such as noise and electromagnetic emissions. The part of the tram line used for the tests is described and the results are discussed. Other power storage systems using flywheels and capacitors are reviewed.

  18. The Effects of Liberalisation of the Passenger Railway Market on the Situation of Regional Rail Connections in Poland, Czech Republic, Slovakia and Austria

    Directory of Open Access Journals (Sweden)

    Taczanowski Jakub

    2015-09-01

    Full Text Available Liberalisation of railway market can be an important instrument for increasing the attractiveness of local rail services and consequently for making the railways more competitive with other means of transport, which could result in changing the modal share in the favour of railways. The differences in the railway liberalisation level as well as in the policies towards rail transport between Central and Eastern European countries are vast, hence the present situation and the future prospects of regional services are diverse. Whereas there is only one railway line in Slovakia which is not operated by the state railway company ZSSK, a few private local connections which complement a very dense network of ČD state railways are in service in the Czech Republic. Poland, by contrast, is a country where liberalisation of railway market is most advanced as several different companies are responsible for transport in the regions. However, the results of this large scale liberalisation are ambiguous as the positive effects (reopening of some lines are balanced by isolation of the new regional government-owned systems from each other. In Austria, by contrast, the existence of several private and regional government-owned local railways which are an indispensable part of the regional transport networks has contributed to maintain an effective transport system. Although the effects of liberalisation on the local railway networks can often be ambiguous, several cases from the Czech Republic, Austria and Poland show that privatisation and municipalisation may have a positive effect on the railway service as it has enabled to maintain the service on many sections which were at risk of closure. However, the most important condition of the effective transport development seems to be an active cooperation between the railway operators and the local governments as an expression of appropriate transport policy.

  19. Mathematical modeling of a radio-frequency path for IEEE 802.11ah based wireless sensor networks

    Science.gov (United States)

    Tyshchenko, Igor; Cherepanov, Alexander; Dmitrii, Vakhnin; Popova, Mariia

    2017-09-01

    This article discusses the process of creating the mathematical model of a radio-frequency path for an IEEE 802.11ah based wireless sensor networks using M atLab Simulink CAD tools. In addition, it describes occurring perturbing effects and determining the presence of a useful signal in the received mixture.

  20. Impact of service quality management (SQM) practices on Indian railways : study of South Central Railways.

    Science.gov (United States)

    2010-09-01

    The main objective of this study is to present a framework developed for assisting Railways to monitor and : control the quality of services provided to passengers. The study evaluated the passenger Rail Service quality of : Indian Railways by develo...

  1. Dynamic response of railway tracks in tunnel

    OpenAIRE

    Hoang , T; Duhamel , Denis; Forêt , Gilles; Yin , H.P.; Joyez , P; Caby , R

    2014-01-01

    International audience; Periodically supported beams subjected to a moving load are often used for modelling the railway dynamics and analytical solutions have been developed for such modelling [3, 4]. More complex models can be constructed by including supports with damping or non-linear stiffness elements. This study deals with the dynamical modelling of non-ballasted railways, especially railways in tunnels. The model is developed as a dynamical system of multi-degree of freedom. Under the...

  2. Existing Steel Railway Bridges Evaluation

    Science.gov (United States)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  3. Existing Steel Railway Bridges Evaluation

    Directory of Open Access Journals (Sweden)

    Vičan Josef

    2016-12-01

    Full Text Available The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  4. Structural Health and Stability Assessment of High-Speed Railways via Thermal Dilation Mapping With Time-Series InSAR Analysis

    NARCIS (Netherlands)

    Qin, Xiaoqiong; Liao, Mingsheng; Zhang, L; Yang, M.

    2017-01-01

    Thermal dilation is a vital component of deformation along the extensive railway network infrastructure. To monitor subtle deformation, the synthetic aperture radar interferometry (InSAR) technique has been adopted as a space-borne geodetic tool. However, InSAR applications in railway stability

  5. 76 FR 59482 - The New Brunswick Railway Company-Continuance in Control Exemption-Maine Northern Railway Company...

    Science.gov (United States)

    2011-09-26

    ... requirements of 49 U.S.C. 11323-25, for Eastern Maine Railway, a Class III rail common carrier to continue in... Exemption-- Montreal, Maine & Atlantic Railway, Ltd.; Maine Northern Railway Company--Modified Rail...

  6. A Branch-and-Price algorithm for railway rolling stock rescheduling

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Haahr, Jørgen Thorlund; Larsen, Jesper

    2017-01-01

    How to best reschedule their fleet of rolling stock units during a disruption is an optimization problem regularly faced by railway operators. Despite the problem’s high complexity, it is still usually solved manually. In this paper we propose a path based mathematical formulation and solve...... by the suburban railway operator in Copenhagen, DSB S-tog. When used in combination with a lower bound method taken from the literature we show that near-optimal solutions to this rescheduling problem can be found within a few seconds. Furthermore, we show that the proposed methodology can be used, with minor...

  7. Estimating emissions from railway traffic

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, M.W.; Sorenson, C.

    1997-07-01

    The report discusses methods that can be used to estimate the emissions from various kinds of railway traffic. The methods are based on the estimation of the energy consumption of the train, so that comparisons can be made between electric and diesel driven trains. Typical values are given for the necessary traffic parameters, emission factors, and train loading. Detailed models for train energy consumption are presented, as well as empirically based methods using average train speed and distance between stop. (au)

  8. Progress in Industrial Mathematics at ECMI 96

    DEFF Research Database (Denmark)

    mathematicians get inspiration from industrial demands. The European Consortium for Mathematics in Industry aims to create contact between industry and academia, and to promote research in industrial mathematics. This book contains a broad spectrum of mathematics applied to industrial problems. Applied...... mathematics, case studies, and review papers in the following fields are included: Environmental modelling, railway systems, industrial processes, electronics, ships, oil industry, optimization, machine dynamics, fluids in industry. Applied mathematicians and other professionals working in academia...

  9. Time-Dependent Topology of Railway Prestressed Concrete Sleepers

    Science.gov (United States)

    Li, Dan; Ngamkhanong, Chayut; Kaewunruen, Sakdirat

    2017-10-01

    The railway sleepers are very important component of railway track structure. The sleepers can be manufactured by using timber, concrete, steel or other engineered materials. Nowadays, prestressed concrete has become most commonly used type of sleepers. Prestressed concrete sleepers have longer life-cycle and lower maintenance cost than reinforced concrete sleepers. They are expected to withstand high dynamic loads and harsh environments. However, durability and long-term performance of prestressed concrete sleepers are largely dependent on creep and shrinkage responses. This study investigates the long-term behaviours of prestressed concrete sleepers and proposes the shortening and deflection diagrams. Comparison between design codes of Eurocode 2 and AS3600-2009 provides the insight into the time-dependent performance of prestressed concrete sleepers. The outcome of this paper will improve the rail maintenance and inspection criteria in order to establish appropriate sensible remote track condition monitor network in practice.

  10. Curriculum Framework (CF) Implementation Conference. Report of the Regional Educational Laboratory Network Program and the National Network of Eisenhower Mathematics and Science Regional Consortia (Hilton Head Island, South Carolina, January 26-27, 1995).

    Science.gov (United States)

    Palmer, Jackie; Powell, Mary Jo

    The Laboratory Network Program and the National Network of Eisenhower Mathematics and Science Regional Consortia, operating as the Curriculum Frameworks Task Force, jointly convened a group of educators involved in implementing state-level mathematics or science curriculum frameworks (CF). The Hilton Head (South Carolina) conference had a dual…

  11. Structural impact response for assessing railway vibration induced on buildings

    Science.gov (United States)

    Kouroussis, Georges; Mouzakis, Harris P.; Vogiatzis, Konstantinos E.

    2018-03-01

    Over the syears, the rapid growth in railway infrastructure has led to numerous environmental challenges. One such significant issue, particularly in urban areas, is ground-borne vibration. A common source of ground-borne vibration is caused by local defects (e.g. rail joints, switches, turnouts, etc.) that generate large amplitude excitations at isolated locations. Modelling these excitation sources is particularly challenging and requires the use of complex and extensive computational efforts. For some situations, the use of experiments and measured data offers a rapid way to estimate the effect of such defects and to evaluate the railway vibration levels using a scoping approach. In this paper, the problem of railway-induced ground vibrations is presented along with experimental studies to assess the ground vibration and ground borne noise levels, with a particular focus on the structural response of sensitive buildings. The behaviour of particular building foundations is evaluated through experimental data collected in Brussels Region, by presenting the expected frequency responses for various types of buildings, taking into account both the soil-structure interaction and the tramway track response. A second study is dedicated to the Athens metro, where transmissibility functions are used to analyse the effect of various Athenian building face to metro network trough comprehensive measurement campaigns. This allows the verification of appropriate vibration mitigation measures. These benchmark applications based on experimental results have been proved to be efficient to treat a complex problem encountered in practice in urban areas, where the urban rail network interacts with important local defects and where the rise of railway ground vibration problems has clearly been identified.

  12. Optimal location of emergency stations in underground mine networks using a multiobjective mathematical model.

    Science.gov (United States)

    Lotfian, Reza; Najafi, Mehdi

    2018-02-26

    Background Every year, many mining accidents occur in underground mines all over the world resulting in the death and maiming of many miners and heavy financial losses to mining companies. Underground mining accounts for an increasing share of these events due to their special circumstances and the risks of working therein. Thus, the optimal location of emergency stations within the network of an underground mine in order to provide medical first aid and transport injured people at the right time, plays an essential role in reducing deaths and disabilities caused by accidents Objective The main objective of this study is to determine the location of emergency stations (ES) within the network of an underground coal mine in order to minimize the outreach time for the injured. Methods A three-objective mathematical model is presented for placement of ES facility location selection and allocation of facilities to the injured in various stopes. Results Taking into account the radius of influence for each ES, the proposed model is capable to reduce the maximum time for provision of emergency services in the event of accident for each stope. In addition, the coverage or lack of coverage of each stope by any of the emergency facility is determined by means of Floyd-Warshall algorithm and graph. To solve the problem, a global criterion method using GAMS software is used to evaluate the accuracy and efficiency of the model. Conclusions 7 locations were selected from among 46 candidates for the establishment of emergency facilities in Tabas underground coal mine. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. System network planning expansion using mathematical programming, genetic algorithms and tabu search

    International Nuclear Information System (INIS)

    Sadegheih, A.; Drake, P.R.

    2008-01-01

    In this paper, system network planning expansion is formulated for mixed integer programming, a genetic algorithm (GA) and tabu search (TS). Compared with other optimization methods, GAs are suitable for traversing large search spaces, since they can do this relatively rapidly and because the use of mutation diverts the method away from local minima, which will tend to become more common as the search space increases in size. GA's give an excellent trade off between solution quality and computing time and flexibility for taking into account specific constraints in real situations. TS has emerged as a new, highly efficient, search paradigm for finding quality solutions to combinatorial problems. It is characterized by gathering knowledge during the search and subsequently profiting from this knowledge. The attractiveness of the technique comes from its ability to escape local optimality. The cost function of this problem consists of the capital investment cost in discrete form, the cost of transmission losses and the power generation costs. The DC load flow equations for the network are embedded in the constraints of the mathematical model to avoid sub-optimal solutions that can arise if the enforcement of such constraints is done in an indirect way. The solution of the model gives the best line additions and also provides information regarding the optimal generation at each generation point. This method of solution is demonstrated on the expansion of a 10 bus bar system to 18 bus bars. Finally, a steady-state genetic algorithm is employed rather than generational replacement, also uniform crossover is used

  14. Origins of the brain networks for advanced mathematics in expert mathematicians.

    Science.gov (United States)

    Amalric, Marie; Dehaene, Stanislas

    2016-05-03

    The origins of human abilities for mathematics are debated: Some theories suggest that they are founded upon evolutionarily ancient brain circuits for number and space and others that they are grounded in language competence. To evaluate what brain systems underlie higher mathematics, we scanned professional mathematicians and mathematically naive subjects of equal academic standing as they evaluated the truth of advanced mathematical and nonmathematical statements. In professional mathematicians only, mathematical statements, whether in algebra, analysis, topology or geometry, activated a reproducible set of bilateral frontal, Intraparietal, and ventrolateral temporal regions. Crucially, these activations spared areas related to language and to general-knowledge semantics. Rather, mathematical judgments were related to an amplification of brain activity at sites that are activated by numbers and formulas in nonmathematicians, with a corresponding reduction in nearby face responses. The evidence suggests that high-level mathematical expertise and basic number sense share common roots in a nonlinguistic brain circuit.

  15. The keys to Europe : regulating railways

    NARCIS (Netherlands)

    2012-01-01

    The expansion of the railways in Europe in the middle of the nineteenth century quickly raised new questions about harmonizing standards to allow them to travel over national borders. Negotiations regarding how to run international railways involved entrepreneurs, engineers, and politicians from

  16. A Polynomial Estimate of Railway Line Delay

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Harrod, Steven; Nielsen, Otto Anker

    2017-01-01

    Railway service may be measured by the aggregate delay over a time horizon or due to an event. Timetables for railway service may dampen aggregate delay by addition of additional process time, either supplement time or buffer time. The evaluation of these variables has previously been performed...

  17. NEW POSSIBILITIES OF RAILWAY TRAFFIC CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lionginas LIUDVINAVIČIUS

    2016-06-01

    Full Text Available This article analyses the train traffic control systems in 1435 mm and 1520 mm gauge railways. The article analyses the aspects of train traffic control and locomotive energy saving by using the coordinates of track profile change that have been received from GPS. In the article, achievements of Lithuanian railways (LG in the area of train traffic control optimisation are presented.

  18. Railway timetabling from an operations research

    NARCIS (Netherlands)

    L.G. Kroon (Leo); D. Huisman (Dennis); G. Maróti (Gábor)

    2007-01-01

    textabstractIn this paper we describe Operations Research (OR) models and techniques that can be used for determining (cyclic) railway timetables. We discuss the two aspects of railway timetabling: ($i$) the determination of arrival and departure times of the trains at the stations and other

  19. Modeling and analysis of a biomorph piezoelectric energy harvester for railway bridge monitoring

    Science.gov (United States)

    Li, Jingcheng; Jang, Shinae; Tang, Jiong

    2012-04-01

    Wireless sensor network is one of prospective methods for railway bridge health monitoring. It has drawn much attention due to the long-term operation and low-maintenance performances. However, how to provide power to wireless sensors is a big issue. In railway health monitoring, the idea of converting ambient vibration energy from the vibration of railway track induced by passing train to electric energy has made it an efficient way for powering the wireless sensor networks. In this paper, a bimorph piezoelectric energy harvester from base excitation was investigated in the laboratory, and the energy output of the bimorph energy harvester was predicted by an equivalent single-degree-of-freedom (SDOF) model. Reasonable results have been found between the tested and predicted data. Based on the theoretical model, further works on optimization of the bimorph piezoelectric energy harvester will be performed in future.

  20. Disruption Management in Passenger Railway Transportation

    DEFF Research Database (Denmark)

    Jespersen-Groth, Julie; Potthoff, Daniel; Clausen, Jens

    This paper deals with disruption management in passenger railway transportation. In the disruption management process, many actors belonging to different organizations play a role. In this paper we therefore describe the process itself and the roles of the different actors. Furthermore, we discuss...... the three main subproblems in railway disruption management: timetable adjustment, and rolling stock and crew re-scheduling. Next to a general description of these problems, we give an overview of the existing literature and we present some details of the specific situations at DSB S-tog and NS....... These are the railway operators in the suburban area of Copenhagen, Denmark, and on the main railway lines in the Netherlands, respectively. Since not much research has been carried out yet on Operations Research models for disruption management in the railway context, models and techniques that have been developed...

  1. Design of a bimorph piezoelectric energy harvester for railway monitoring

    International Nuclear Information System (INIS)

    Li, Jingcheng; Jang, Shinae; Tang, Jiong

    2012-01-01

    Wireless sensor network is one of prospective methods for railway monitoring due to the long term operation and low maintenance performances. How to supply power to the wireless sensor nodes has drawn much attention recently. In railway monitoring, the idea of converting ambient vibration energy from vibration of railway track induced by passing trains to electric energy has made it a potential way for powering the wireless sensor nodes. In this paper, a bimorph cantilever piezoelectric energy harvester was designed based on a single degree of freedom model. Experimental test was also performed to validate the design. The first natural frequency of the bimorph piezoelectric energy harvester was decreased from 117.1 Hz to 65.2 Hz by adding 4 gram tip mass to the free end of the 8.6 gram energy harvester. In addition, the power generation of the piezoelectric energy harvester with 4 gram tip mass at resonant frequency was increased from 0.14 mW to 0.74 mW from 2.06 m/s 2 base excitation compared to stand alone piezoelectric energy harvester without tip mass

  2. Design of a bimorph piezoelectric energy harvester for railway monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jingcheng; Jang, Shinae; Tang, Jiong [Univ. of Connecticut, Connecticut (United States)

    2012-12-15

    Wireless sensor network is one of prospective methods for railway monitoring due to the long term operation and low maintenance performances. How to supply power to the wireless sensor nodes has drawn much attention recently. In railway monitoring, the idea of converting ambient vibration energy from vibration of railway track induced by passing trains to electric energy has made it a potential way for powering the wireless sensor nodes. In this paper, a bimorph cantilever piezoelectric energy harvester was designed based on a single degree of freedom model. Experimental test was also performed to validate the design. The first natural frequency of the bimorph piezoelectric energy harvester was decreased from 117.1 Hz to 65.2 Hz by adding 4 gram tip mass to the free end of the 8.6 gram energy harvester. In addition, the power generation of the piezoelectric energy harvester with 4 gram tip mass at resonant frequency was increased from 0.14 mW to 0.74 mW from 2.06 m/s{sup 2} base excitation compared to stand alone piezoelectric energy harvester without tip mass.

  3. Comparison of Annoyance from Railway Noise and Railway Vibration.

    Science.gov (United States)

    Ögren, Mikael; Gidlöf-Gunnarsson, Anita; Smith, Michael; Gustavsson, Sara; Persson Waye, Kerstin

    2017-07-19

    The aim of this study is to compare vibration exposure to noise exposure from railway traffic in terms of equal annoyance, i.e., to determine when a certain noise level is equally annoying as a corresponding vibration velocity. Based on questionnaire data from the Train Vibration and Noise Effects (TVANE) research project from residential areas exposed to railway noise and vibration, the dose response relationship for annoyance was estimated. By comparing the relationships between exposure and annoyance for areas both with and without significant vibration exposure, the noise levels and vibration velocities that had an equal probability of causing annoyance was determined using logistic regression. The comparison gives a continuous mapping between vibration velocity in the ground and a corresponding noise level at the facade that are equally annoying. For equivalent noise level at the facade compared to maximum weighted vibration velocity in the ground the probability of annoyance is approximately 20% for 59 dB or 0.48 mm/s, and about 40% for 63 dB or 0.98 mm/s.

  4. Assessing The Impact Of Railway Restructuring In Nigeria | Ibe ...

    African Journals Online (AJOL)

    The study presents railway restructuring as a solution option to railway problems in Nigeria. It aims at ascertaining the efficiency of the critical input factors of Nigerian Railway corporation (NRC) while comparing it with that of the restructured developed and best practices railways to establish the basis for restructuring.

  5. [Research on China railway health campaign in 1930s].

    Science.gov (United States)

    Huang, Huaping

    2015-01-01

    The motivation factors of China's railway health campaign in 1930s included avocation by the government, mass media mobilization, railway authorities' hygiene awareness and the systematization of the construction of organization. During the health campaign, the railway authorities adopted various approaches for its formation, including the rally speeches, distribution of materials, cleaning and vaccination etc. Unfortunately, the actual effect of railway health campaign was not satisfactory, yet, it enhanced theoretically railway employees' health knowledge and contributed to the promotion of modernization of hygienic knowledge. Meanwhile, there still existed many problems in the railway health campaign, for example, lack of funds, formalism and uneven development among the railway bureaus.

  6. Smart Girls, Black Girls, Mean Girls, and Bullies: At the Intersection of Identities and the Mediating Role of Young Girls' Social Network in Mathematical Communities of Practice

    Science.gov (United States)

    Gholson, Maisie; Martin, Danny B.

    2014-01-01

    By taking an intersectional and emic view to studying a group of African American girls in a third-grade class, we attempted to capture the complexity of mathematics learning for these girls. Traditionally, children's social networks in school are framed as external to mathematics content learning. Our preliminary analyses of student interviews…

  7. 78 FR 56769 - South Carolina Division of Public Railways, d/b/a Palmetto Railways-Intra-Corporate Family...

    Science.gov (United States)

    2013-09-13

    ... Cooper and Berkeley Railroad Company South Carolina Division of Public Railways, d/b/a Palmetto Railways... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35762] South Carolina Division of Public Railways, d/b/a Palmetto Railways--Intra-Corporate Family Transaction Exemption--The...

  8. A semi-empirical model for the prediction of fouling in railway ballast using GPR

    Science.gov (United States)

    Bianchini Ciampoli, Luca; Tosti, Fabio; Benedetto, Andrea; Alani, Amir M.; Loizos, Andreas; D'Amico, Fabrizio; Calvi, Alessandro

    2016-04-01

    The first step in the planning for a renewal of a railway network consists in gathering information, as effectively as possible, about the state of the railway tracks. Nowadays, this activity is mostly carried out by digging trenches at regular intervals along the whole network, to evaluate both geometrical and geotechnical properties of the railway track bed. This involves issues, mainly concerning the invasiveness of the operations, the impacts on the rail traffic, the high costs, and the low levels of significance concerning such discrete data set. Ground-penetrating radar (GPR) can represent a useful technique for overstepping these issues, as it can be directly mounted onto a train crossing the railway, and collect continuous information along the network. This study is aimed at defining an empirical model for the prediction of fouling in railway ballast, by using GPR. With this purpose, a thorough laboratory campaign was implemented within the facilities of Roma Tre University. In more details, a 1.47 m long × 1.47 m wide × 0.48 m height plexiglass framework, accounting for the domain of investigation, was laid over a perfect electric conductor, and filled up with several configuration of railway ballast and fouling material (clayey sand), thereby representing different levels of fouling. Then, the set of fouling configurations was surveyed with several GPR systems. In particular, a ground-coupled multi-channel radar (600 MHz and 1600 MHz center frequency antennas) and three air-launched radar systems (1000 MHz and 2000 MHz center frequency antennas) were employed for surveying the materials. By observing the results both in terms of time and frequency domains, interesting insights are highlighted and an empirical model, relating in particular the shape of the frequency spectrum of the signal and the percentage of fouling characterizing the surveyed material, is finally proposed. Acknowledgement The Authors thank COST, for funding the Action TU1208 "Civil

  9. Place-making around high-speed railway stations in China

    NARCIS (Netherlands)

    Dai, G.

    2015-01-01

    The rapid expansion of the High-Speed Railway (HSR) network in China generates leapfrog urbanization on the urban periphery in the forms of ambitious blueprint plan around the mega hubs. Nevertheless, most of the station areas and spatial extension lack "place quality". The place-making process of

  10. A Polynomial Estimate of Railway Line Delay

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Harrod, Steven; Nielsen, Otto Anker

    2017-01-01

    Railway service may be measured by the aggregate delay over a time horizon or due to an event. Timetables for railway service may dampen aggregate delay by addition of additional process time, either supplement time or buffer time. The evaluation of these variables has previously been performed...... by numerical analysis with simulation. This paper proposes an analytical estimate of aggregate delay with a polynomial form. The function returns the aggregate delay of a railway line resulting from an initial, primary, delay. Analysis of the function demonstrates that there should be a balance between the two...

  11. SURVEY RESULTS AND TESTING OF RAILWAY BRIDGES

    Directory of Open Access Journals (Sweden)

    I. H. Haniiev

    2010-03-01

    Full Text Available The article is devoted to the survey and testing of railway bridges by the State Joint-Stock Railway Company «Uzbekiston Temir Yollari» («Uzbekistan Railways». It is stated that in the existing rules on determination of the capacity of bridges the recommendations on taking into account the cumulative deflection to the moment of technical diagnostics of spans on the bridge capacity are absent. The author states on the need to develop a method for determining the wear of spans on restriction of the residual deflection in the bridge floor slabs.

  12. A Unifying Mathematical Framework for Genetic Robustness, Environmental Robustness, Network Robustness and their Trade-offs on Phenotype Robustness in Biological Networks. Part III: Synthetic Gene Networks in Synthetic Biology

    Science.gov (United States)

    Chen, Bor-Sen; Lin, Ying-Po

    2013-01-01

    Robust stabilization and environmental disturbance attenuation are ubiquitous systematic properties that are observed in biological systems at many different levels. The underlying principles for robust stabilization and environmental disturbance attenuation are universal to both complex biological systems and sophisticated engineering systems. In many biological networks, network robustness should be large enough to confer: intrinsic robustness for tolerating intrinsic parameter fluctuations; genetic robustness for buffering genetic variations; and environmental robustness for resisting environmental disturbances. Network robustness is needed so phenotype stability of biological network can be maintained, guaranteeing phenotype robustness. Synthetic biology is foreseen to have important applications in biotechnology and medicine; it is expected to contribute significantly to a better understanding of functioning of complex biological systems. This paper presents a unifying mathematical framework for investigating the principles of both robust stabilization and environmental disturbance attenuation for synthetic gene networks in synthetic biology. Further, from the unifying mathematical framework, we found that the phenotype robustness criterion for synthetic gene networks is the following: if intrinsic robustness + genetic robustness + environmental robustness ≦ network robustness, then the phenotype robustness can be maintained in spite of intrinsic parameter fluctuations, genetic variations, and environmental disturbances. Therefore, the trade-offs between intrinsic robustness, genetic robustness, environmental robustness, and network robustness in synthetic biology can also be investigated through corresponding phenotype robustness criteria from the systematic point of view. Finally, a robust synthetic design that involves network evolution algorithms with desired behavior under intrinsic parameter fluctuations, genetic variations, and environmental

  13. Influence of Surface Abrasion on Creep and Shrinkage of Railway Prestressed Concrete Sleepers

    Science.gov (United States)

    Li, Dan; Ngamkhanong, Chayut; Kaewunruen, Sakdirat

    2017-10-01

    Ballasted railway track is very suitable for heavy-rail networks because of its many superior advantages in design, construction, short- and long-term maintenance, sustainability, and life-cycle cost. The sleeper, which supports rail and distributes loads from rail to ballast, is a very important component of rail track system. Prestressed concrete is very popular used in manufacturing sleepers. Therefore, improved knowledge about design techniques for prestressed concrete (PC) sleepers has been developed. However, the ballast angularity causes differential abrasions on the soffit or bottom surface of sleepers. Furthermore, in sharp curves and rapid gradient change, longitudinal and lateral dynamics of rails increase the likelihood of abrasions in concrete sleepers. This paper presents a comparative investigation using a variety of methods to evaluate creep and shrinkage effects in railway prestressed concrete sleepers. The outcome of this study will improve the material design, which is very critical to the durability of railway track components.

  14. Advanced Fade Countermeasures for DVB-S2 Systems in Railway Scenarios

    Directory of Open Access Journals (Sweden)

    Niebla CristinaPárraga

    2007-01-01

    Full Text Available This paper deals with the analysis of advanced fade countermeasures for supporting DVB-S2 reception by mobile terminals mounted on high-speed trains. Recent market studies indicate this as a potential profitable market for satellite communications, provided that integration with wireless terrestrial networks can be implemented to bridge the satellite connectivity inside railway tunnels and large train stations. In turn, the satellite can typically offer the coverage of around 80% of the railway path with existing space infrastructure. This piece of work, representing the first step of a wider study, is focusing on the modifications which may be required in the DVB-S2 standard (to be employed in the forward link in order to achieve reliable reception in a challenging environment such as the railway one. Modifications have been devised trying to minimize the impact on the existing air interface, standardized for fixed terminals.

  15. Advanced Fade Countermeasures for DVB-S2 Systems in Railway Scenarios

    Directory of Open Access Journals (Sweden)

    Cristina Párraga Niebla

    2007-07-01

    Full Text Available This paper deals with the analysis of advanced fade countermeasures for supporting DVB-S2 reception by mobile terminals mounted on high-speed trains. Recent market studies indicate this as a potential profitable market for satellite communications, provided that integration with wireless terrestrial networks can be implemented to bridge the satellite connectivity inside railway tunnels and large train stations. In turn, the satellite can typically offer the coverage of around 80% of the railway path with existing space infrastructure. This piece of work, representing the first step of a wider study, is focusing on the modifications which may be required in the DVB-S2 standard (to be employed in the forward link in order to achieve reliable reception in a challenging environment such as the railway one. Modifications have been devised trying to minimize the impact on the existing air interface, standardized for fixed terminals.

  16. Modelling and modal properties of the railway vehicle bogie with two individual wheelset drives

    Directory of Open Access Journals (Sweden)

    Zeman V.

    2007-10-01

    Full Text Available The paper deals with mathematical modelling of vibration and modal analysis of two-axled bogie of a railway vehicle. In comparison with recent publications introducing mathematical models of an individual wheelset drive, this paper is focused on modelling of complex bogie vibration. The bogie frame is linked by primary suspension to the two wheelset drives with hollow shafts and by secondary suspension to the car body. The method is based on the system decomposition into three subsystems – two individual wheelset drives including the mass of the rail and the bogie frame coupled with a half of the car body – and on modelling of couplings among subsystems. The eigenvalues of a linearized autonomous model and stability conditions are investigated in dependence on longitudinal creepage and forward velocity of the railway vehicle. The nonlinear model will be used for investigating the dynamic loading of bogie components caused by different types of excitation.

  17. A review of mathematical models for the formation of vascular networks

    KAUST Repository

    Scianna, M.; Bell, C.G.; Preziosi, L.

    2013-01-01

    process generally called lymphangiogenesis. A number of mathematical approaches have been used to analyze these phenomena. In this paper, we review the different types of models, with special emphasis on their ability to reproduce different biological

  18. AN AUTOMATED RAILWAY STATION TRAFFIC CONTROL SYSTEM

    African Journals Online (AJOL)

    AN AUTOMATED RAILWAY STATION TRAFFIC CONTROL SYSTEM. ... involve collision with automobiles or other vehicles and collision with other trains. ... the processed signals to control electromagnetic devices through motor drivers.

  19. High-speed railways in Japan

    International Nuclear Information System (INIS)

    Kyotani, Y.

    1974-01-01

    This paper reviews the development of conventional railways in Japan, leading up to the Shinkansen line, which at present runs at speeds up to 210km/h, and will in the future be speeded up to 260km/h. It then goes on to review the development of a superconductive, magnetically levitated train, which will constitute the next generation of railways, running at speeds of up to 500km/h. (author)

  20. Digital Model of Railway Electric Traction Lines

    Science.gov (United States)

    Garg, Rachana; Mahajan, Priya; Kumar, Parmod

    2017-08-01

    The characteristic impedance and propagation constant define the behavior of signal propagation over the transmission lines. The digital model for railway traction lines which includes railway tracks is developed, using curve fitting technique in MATLAB. The sensitivity of this model has been computed with respect to frequency. The digital sensitivity values are compared with the values of analog sensitivity. The developed model is useful for digital protection, integrated operation, control and planning of the system.

  1. Mine railway equipments management information system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X.; Han, K.; Duan, T.; Liu, Z.; Lu, H. [China University of Mining and Technology, Xuzhou (China)

    2007-06-15

    Based on client/server and browser/server models, the management information system described realized the entire life-cycle management of mine railway equipment which included universal equipment and special equipment in the locomotive depot, track maintenance division, electrical depot and car depot. The system has other online functions such as transmitting reports, graphics management, statistics, searches, graphics wizard and web propaganda. It was applied in Pingdingshan Coal Co. Ltd.'s Railway Transport Department. 5 refs., 4 figs.

  2. The liberalisation of the railways in Europe

    OpenAIRE

    Trampus, Francesca

    2000-01-01

    It is certainly high time to talk about policy for the railways not only in the Russian Federation but also in Europe, where the railways are vital part of the Community transport sector and need to be promoted and revitalized, especially considering the increasing air-traffic and railroad congestion, the environmental problems, the traffic noise, the accidents and the growing opposition to the unchecked development of the new road infrastructure. Railtrack’s business is supported by state-fu...

  3. Model for Railway Infrastructure Management Organization

    Directory of Open Access Journals (Sweden)

    Gordan Stojić

    2012-03-01

    Full Text Available The provision of appropriate quality rail services has an important role in terms of railway infrastructure: quality of infrastructure maintenance, regulation of railway traffic, line capacity, speed, safety, train station organization, the allowable lines load and other infrastructure parameters.The analysis of experiences in transforming the railway systems points to the conclusion that there is no unique solution in terms of choice for institutional rail infrastructure management modes, although more than nineteen years have passed from the beginning of the implementation of the Directive 91/440/EEC. Depending on the approach to the process of restructuring the national railway company, adopted regulations and caution in its implementation, the existence or absence of a clearly defined transport strategy, the willingness to liberalize the transport market, there are several different ways for institutional management of railway infrastructure.A hybrid model for selection of modes of institutional rail infrastructure management was developed based on the theory of artificial intelligence, theory of fuzzy sets and theory of multicriteria optimization.KEY WORDSmanagement, railway infrastructure, organizational structure, hybrid model

  4. Gantry Crane Scheduling with Interference Constraints in Railway Container Terminals

    Directory of Open Access Journals (Sweden)

    Peng Guo

    2013-04-01

    Full Text Available Railway container terminals, where gantry cranes are responsible for loading and unloading containers between freight trains and yards, are important hubs of hinterland logistics transportation. Terminal managers confront the challenge in improving the efficiency of their service. As the most expensive equipment in a terminal, the operational performance of gantry cranes is a crucial factor. In this paper, the gantry crane scheduling problem of railway container terminals is investigated. A mixed integer programming model which considers the effect of dwelling position dependent processing times is formulated. In addition, the safety distances, the travel times and the non-crossing requirement of cranes are incorporated in the mathematical model. A novel discrete artificial bee colony algorithm is presented to solve the intractable scheduling problem. Computational experiments are conducted to evaluate the proposed algorithm on some randomly constructed instances based on typical terminal operational data. Experimental results show that the proposed approach can obtain near optimal solutions for the investigated problem in a reasonable computational time.

  5. Investigation on energy efficient sensor node placement in railway systems

    Directory of Open Access Journals (Sweden)

    Ayona Philipose

    2016-06-01

    Full Text Available Recently wireless sensor network (WSN has been widely used for monitoring railway tracks and rail tunnels. The key requirement in the design of such WSN is to minimize the energy consumption so as to maximize the network lifetime. This paper includes the performance of an improved medium access control (MAC protocol, namely, time adaptive-bit map assisted (TA-BMA protocol, for the purpose of communication between the sensors placed in a railway wagon. The train is considered to be moving at a constant speed, and the sensor nodes are stationary with respect to the motion of train. The effect of mobility on the proposed MAC protocol is determined using genetic algorithm (GA, and the observed increase in energy consumption on considering mobility is 18.51%. Performance analysis of the system model is carried out using QualNet (ver. 7.1, and the energy consumption in transmit mode, receive mode, percentage of time in sleep mode, end-to-end delay and throughput are investigated.

  6. A Network for Integrated Science and Mathematics Teaching and Learning. NCSTL Monograph Series, #2.

    Science.gov (United States)

    Berlin, Donna F.; White, Arthur L.

    This monograph presents a summary of the results of the Wingspread Conference in April, 1991 concerning the viability and future of the concept of integration of mathematics and science teaching and learning. The conference focused on three critical issues: (1) development of definitions of integration and a rationale for integrated teaching and…

  7. Meteorological tools in support to the railway security system on the Calabria region

    Science.gov (United States)

    Laviola, Sante; Gabriele, Salvatore; Iovine, Giulio; Baldini, Luca; Chiravalloti, Francesco; Federico, Stefano; Miglietta, Marcello Mario; Milani, Lisa; Procopio, Antonio; Roberto, Nicoletta; Tiesi, Alessandro; Agostino, Mario; Niccoli, Raffaele; Stassi, Sergio; Rago, Valeria

    2017-04-01

    RAMSES (RAilway Meteorological SEcurity System) is a pilot project co-funded by the Italian Railway Company - RFI S.p.A. and conceived for the mitigation of the hydrological risk along the Calabria railways. RAMSES aims at improving the forecast of very short life-cycle convection systems, responsible of intense and localized rainfalls affecting small catchment areas, which are often underestimated by the numerical weather models and even non-adequately detected by the network of sparse raingauges. The RAMSES operational design is based on a synergistic and integrated architecture, providing a series of information able to identify the most active convective cells and monitoring their evolution in terms of vertical structure, rain intensity and geo-hydrological effects at ground (debris flow, landslides, collapses of bridges, erosion of the ballast). The RAMSES meteorological component is designed to identify and track the short-term evolution (15-60 min) of convective cells, by means of imaging techniques based on dual-polarization weather radar and Meteosat data. In support of this quasi-real time analysis, the numerical model WRF provides the weather forecast at 3-6 hours range by ingesting, through the assimilation system LAPS, the observational data (rain gauges, ground weather stations, radar, satellites) in order to improve the initial condition. Finally, the hydraulic flow modeling is used to assess the ground effects in terms of landslide susceptibility, rainfall-runoff intensity, debris impact on the drainage network and evaluate of risk along the railway track.

  8. Probabilistic Fatigue Life Updating for Railway Bridges Based on Local Inspection and Repair.

    Science.gov (United States)

    Lee, Young-Joo; Kim, Robin E; Suh, Wonho; Park, Kiwon

    2017-04-24

    Railway bridges are exposed to repeated train loads, which may cause fatigue failure. As critical links in a transportation network, railway bridges are expected to survive for a target period of time, but sometimes they fail earlier than expected. To guarantee the target bridge life, bridge maintenance activities such as local inspection and repair should be undertaken properly. However, this is a challenging task because there are various sources of uncertainty associated with aging bridges, train loads, environmental conditions, and maintenance work. Therefore, to perform optimal risk-based maintenance of railway bridges, it is essential to estimate the probabilistic fatigue life of a railway bridge and update the life information based on the results of local inspections and repair. Recently, a system reliability approach was proposed to evaluate the fatigue failure risk of structural systems and update the prior risk information in various inspection scenarios. However, this approach can handle only a constant-amplitude load and has limitations in considering a cyclic load with varying amplitude levels, which is the major loading pattern generated by train traffic. In addition, it is not feasible to update the prior risk information after bridges are repaired. In this research, the system reliability approach is further developed so that it can handle a varying-amplitude load and update the system-level risk of fatigue failure for railway bridges after inspection and repair. The proposed method is applied to a numerical example of an in-service railway bridge, and the effects of inspection and repair on the probabilistic fatigue life are discussed.

  9. Impact Capacity Reduction in Railway Prestressed Concrete Sleepers with Surface Abrasions

    Science.gov (United States)

    Ngamkhanong, Chayut; Li, Dan; Kaewunruen, Sakdirat

    2017-10-01

    Railway sleepers (also called ‘railroad tie’ in North America) embedded in ballasted railway tracks are a main part of railway track structures. Its important role is to transfer the loads evenly from the rails to a wider area of ballast bed and to secure rail gauge and enable safe passages of rolling stocks. By nature, railway infrastructure is nonlinear, evidenced by its behaviours, geometry and alignment, wheel-rail contact and operational parameters such as tractive efforts. Based on our critical review, the dynamic behaviour of railway sleepers has not been fully investigated, especially when the sleepers are deteriorated by excessive wears. In fact, the ballast angularity causes differential abrasions on the soffit or bottom surface of sleepers (especially at railseat zone). Furthermore, in sharp curves and rapid gradient change, longitudinal and lateral dynamics of rails increase the likelihood of railseat abrasions in concrete sleepers due to the unbalanced loading conditions. This paper presents a structural capacity of concrete sleepers under dynamic transient loading. The modified compression field theory for ultimate strength design of concrete sleepers under impact loading will be highlighted in this study. The influences of surface abrasions, including surface abrasion and soffit abrasion, on the dynamic behaviour of prestressed concrete sleepers, are firstly highlighted. The outcome of this study will improve the rail maintenance and inspection criteria in order to establish appropriate and sensible remote track condition monitoring network in practice. Moreover, this study will also improve the understanding of the fundamental dynamic behaviour of prestressed concrete sleepers with surface abrasions. The insight into these behaviours will not only improve safety and reliability of railway infrastructure but will enhance the structural safety of other concrete structures.

  10. Statistical analysis of cone penetration resistance of railway ballast

    Directory of Open Access Journals (Sweden)

    Saussine Gilles

    2017-01-01

    Full Text Available Dynamic penetrometer tests are widely used in geotechnical studies for soils characterization but their implementation tends to be difficult. The light penetrometer test is able to give information about a cone resistance useful in the field of geotechnics and recently validated as a parameter for the case of coarse granular materials. In order to characterize directly the railway ballast on track and sublayers of ballast, a huge test campaign has been carried out for more than 5 years in order to build up a database composed of 19,000 penetration tests including endoscopic video record on the French railway network. The main objective of this work is to give a first statistical analysis of cone resistance in the coarse granular layer which represents a major component of railway track: the ballast. The results show that the cone resistance (qd increases with depth and presents strong variations corresponding to layers of different natures identified using the endoscopic records. In the first zone corresponding to the top 30cm, (qd increases linearly with a slope of around 1MPa/cm for fresh ballast and fouled ballast. In the second zone below 30cm deep, (qd increases more slowly with a slope of around 0,3MPa/cm and decreases below 50cm. These results show that there is no clear difference between fresh and fouled ballast. Hence, the (qd sensitivity is important and increases with depth. The (qd distribution for a set of tests does not follow a normal distribution. In the upper 30cm layer of ballast of track, data statistical treatment shows that train load and speed do not have any significant impact on the (qd distribution for clean ballast; they increase by 50% the average value of (qd for fouled ballast and increase the thickness as well. Below the 30cm upper layer, train load and speed have a clear impact on the (qd distribution.

  11. Personal Learning Network Clusters: A Comparison between Mathematics and Computer Science Students

    Science.gov (United States)

    Harding, Ansie; Engelbrecht, Johann

    2015-01-01

    "Personal learning environments" (PLEs) and "personal learning networks" (PLNs) are well-known concepts. A personal learning network "cluster" is a small group of people who regularly interact academically and whose PLNs have a non-empty intersection that includes all the other members. At university level PLN…

  12. On the Mathematical Structure of Balanced Chemical Reaction Networks Governed by Mass Action Kinetics

    NARCIS (Netherlands)

    Schaft, Arjan van der; Rao, Shodhan; Jayawardhana, Bayu

    2013-01-01

    Motivated by recent progress on the interplay between graph theory, dynamics, and systems theory, we revisit the analysis of chemical reaction networks described by mass action kinetics. For reaction networks possessing a thermodynamic equilibrium we derive a compact formulation exhibiting at the

  13. A tutorial on fundamental model structures for railway timetable optimization

    DEFF Research Database (Denmark)

    Harrod, Steven

    2012-01-01

    This guide explains the role of railway timetables relative to all other railway scheduling activities, and then presents four fundamental timetable formulations suitable for optimization. Timetabling models may be classified according to whether they explicitly model the track structure, and whe......This guide explains the role of railway timetables relative to all other railway scheduling activities, and then presents four fundamental timetable formulations suitable for optimization. Timetabling models may be classified according to whether they explicitly model the track structure...

  14. A mathematical model for optimization of an integrated network logistic design

    Directory of Open Access Journals (Sweden)

    Lida Tafaghodi

    2011-10-01

    Full Text Available In this study, the integrated forward/reverse logistics network is investigated, and a capacitated multi-stage, multi-product logistics network design is proposed by formulating a generalized logistics network problem into a mixed-integer nonlinear programming model (MINLP for minimizing the total cost of the closed-loop supply chain network. Moreover, the proposed model is solved by using optimization solver, which provides the decisions related to the facility location problem, optimum quantity of shipped product, and facility capacity. Numerical results show the power of the proposed MINLP model to avoid th sub-optimality caused by separate design of forward and reverse logistics networks and to handle various transportation modes and periodic demand.

  15. Methods to estimate railway capacity and passenger delays

    DEFF Research Database (Denmark)

    Landex, Alex

    that an evaluation of passenger delays obtained with simulation software (in this case RailSys) and the passenger delay model is comparable with the daily operation of the Copenhagen suburban railway network. Using a microscopic simulation model, the thesis demonstrates that it is possible to compare travel times...... of additional travel time. The differences between the different kinds of delay (train delays, passenger delays and scheduled waiting time) are illustrated through simple, but representative, case examples in CHAPTER 10. The examples demonstrate that 3rd generation passenger delay models are more realistic than...... depend on the given infrastructure and timetable and can result in longer travel times for trains and passengers. Furthermore, the thesis shows that the network effects can result in reduced capacity as some trains or train services can make it impossible to operate other planned/desired trains or train...

  16. Alignment analysis of urban railways based on passenger travel demand

    DEFF Research Database (Denmark)

    Andersen, Jonas Lohmann Elkjær; Landex, Alex

    2010-01-01

    Planning of urban railways like Metro and especially Light Rail Transit often result in multiple alignment alternatives from where it can be difficult to select the best one. Travel demand is a good foundation for evaluating a railway alignment for its ability to attract passengers. Therefore...... and can be applied as decision support in different stages of the urban railway alignment planning....

  17. 20 CFR 202.15 - Railway labor organizations.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Railway labor organizations. 202.15 Section... EMPLOYERS UNDER THE ACT § 202.15 Railway labor organizations. Railway labor organizations, national in scope... bylaws of such organizations, shall be employers within the meaning of the act. (a) An organization doing...

  18. Effect of Different Structure Type Traffic On Railway Line Capacity

    Directory of Open Access Journals (Sweden)

    Gleba Radosław

    2017-04-01

    Full Text Available The article points to methods of analyzing railway traffic conditions based on two parameters: capacity and delay of trains. The impact of the differentiated railway type structure on the capacity of the railway line was presented. Particular attention has been paid to the assessment of commonly used simplifications in analyzes.

  19. Optimizing targeted vaccination across cyber-physical networks: an empirically based mathematical simulation study.

    Science.gov (United States)

    Mones, Enys; Stopczynski, Arkadiusz; Pentland, Alex 'Sandy'; Hupert, Nathaniel; Lehmann, Sune

    2018-01-01

    Targeted vaccination, whether to minimize the forward transmission of infectious diseases or their clinical impact, is one of the 'holy grails' of modern infectious disease outbreak response, yet it is difficult to achieve in practice due to the challenge of identifying optimal targets in real time. If interruption of disease transmission is the goal, targeting requires knowledge of underlying person-to-person contact networks. Digital communication networks may reflect not only virtual but also physical interactions that could result in disease transmission, but the precise overlap between these cyber and physical networks has never been empirically explored in real-life settings. Here, we study the digital communication activity of more than 500 individuals along with their person-to-person contacts at a 5-min temporal resolution. We then simulate different disease transmission scenarios on the person-to-person physical contact network to determine whether cyber communication networks can be harnessed to advance the goal of targeted vaccination for a disease spreading on the network of physical proximity. We show that individuals selected on the basis of their closeness centrality within cyber networks (what we call 'cyber-directed vaccination') can enhance vaccination campaigns against diseases with short-range (but not full-range) modes of transmission. © 2018 The Author(s).

  20. 11th International Workshop on Railway Noise

    CERN Document Server

    Anderson, David; Gautier, Pierre-Etienne; Iida, Masanobu; Nelson, James; Thompson, David; Tielkes, Thorsten; Towers, David; Vos, Paul

    2015-01-01

    The book reports on the 11th International Workshop on Railway Noise, held on 9 – 13 September, 2013, in Uddevalla, Sweden. The event, which was jointly organized by the Competence Centre Chalmers Railway Mechanics (CHARMEC) and the Departments of Applied Mechanics and Applied Acoustics at Chalmers University of Technology in Gothenburg, Sweden, covered a broad range of topics in the field of railway noise and vibration, including: prospects, legal regulations and perceptions; wheel and rail noise; prediction, measurements and monitoring; ground-borne vibration; squeal noise and structure-borne noise; and aerodynamic noise generated by high-speed trains. Further topics included: resilient track forms; grinding, corrugation and roughness; and interior noise and sound barriers. This book, which consists of a collection of peer-reviewed papers originally submitted to the workshop, not only provides readers with an overview of the latest developments in the field, but also offers scientists and engineers essent...

  1. Lateral dynamic features of a railway vehicle

    DEFF Research Database (Denmark)

    Gao, Xue-jun; True, Hans; Li, Ying-hui

    2016-01-01

    The lateral dynamic features of a railway vehicle are investigated using two similar wheel/rail contact models: the Vermeulen-Johnson and the Shen-Hedrick-Elkins models. The symmetric/asymmetric bifurcation behaviour and chaotic motions of the railway vehicle are investigated in great detail......, resulting in problems for safe operation of the vehicle. Therefore, it should be avoided in everyday operation. Furthermore, the creation of multiple solution branches suggests that the critical speed of a vehicle should be determined from a comprehensive analysis of the various kinds of possible...... by varying the speed and using the resultant bifurcation diagram' method. It is found that multiple solution branches exist and they can lead to more steady states in the dynamic behaviour of the railway vehicle. The coexistence of multiple steady states can lead to jumps in the amplitude of oscillations...

  2. 76 FR 6517 - Carolina Coastal Railway, Inc.-Lease and Operation Exemption-Norfolk Southern Railway Company

    Science.gov (United States)

    2011-02-04

    ... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35461] Carolina Coastal Railway, Inc.--Lease and Operation Exemption-- Norfolk Southern Railway Company Carolina Coastal Railway, Inc. (CLNA), a Class III carrier, has filed a verified notice of exemption \\1\\ under 49 CFR 1150.41 to...

  3. Mathematical Modeling and Analysis Methodology for Opportunistic Routing in Wireless Multihop Networks

    Directory of Open Access Journals (Sweden)

    Wang Dongyang

    2015-01-01

    Full Text Available Modeling the forwarding feature and analyzing the performance theoretically for opportunistic routing in wireless multihop network are of great challenge. To address this issue, a generalized geometric distribution (GGD is firstly proposed. Based on the GGD, the forwarding probability between any two forwarding candidates could be calculated and it can be proved that the successful delivery rate after several transmissions of forwarding candidates is irrelevant to the priority rule. Then, a discrete-time queuing model is proposed to analyze mean end-to-end delay (MED of a regular opportunistic routing with the knowledge of the forwarding probability. By deriving the steady-state joint generating function of the queue length distribution, MED for directly connected networks and some special cases of nondirectly connected networks could be ultimately determined. Besides, an approximation approach is proposed to assess MED for the general cases in the nondirectly connected networks. By comparing with a large number of simulation results, the rationality of the analysis is validated. Both the analysis and simulation results show that MED varies with the number of forwarding candidates, especially when it comes to connected networks; MED increases more rapidly than that in nondirectly connected networks with the increase of the number of forwarding candidates.

  4. Power System Unbalance due to Railway Electrification

    DEFF Research Database (Denmark)

    Stamatopoulos, Athanasios; Vikelgaard, Henrik; Silva, Filipe Miguel Faria da

    2016-01-01

    The decision to electrify the main part of the Danish railway at the same time where the supply and generation of electrical power in Denmark moves to a more decentralized structure, raises concerns regarding the balanced and secure operation of the power grid. Adverse effects include, among others......, the lifetime reduction of rotating machines and the malfunction of HVDC converters. Toward this direction, this paper aims to review the challenges and mitigation solutions with respect to voltage unbalance, focusing on the conditions relevant to the electrification of the Danish railway....

  5. New Porta Susa - Turin Railway Station

    Directory of Open Access Journals (Sweden)

    Silvio d'Ascia

    2011-02-01

    now shared by the ancient railways lines. In that way the city comes inside the station and the station becomes a real part of the city, permeable to pedestrian flows crossed in all directions and at different levels. The internal distribution of the different functional areas is based on a balance program with approximately 10.000 m² of services to travellers and the city (ticket offices, shops, restaurants, bars, terraces, approximately 10.000 m² of hall and public paths and still about 10.000 m² of technical areas, parking and service areas, ... The glass roof (surface of 15.000 m² will be equipped with a photovoltaic system (installed power = 765 kW peak 2300 arranged on the panels that make up 3600 (surface approximately 9.000 m² capable of producing 680,000 KWH’s year of electricity consumed in the public network and corresponding to approximately 35% of domestic needs of future PV, which we hope will become a new symbol for Turin.

  6. Railway power supply - free of crises and independent

    International Nuclear Information System (INIS)

    Weigert, E.

    1981-01-01

    The German Federal Railway realizes 84% of its transport performance by electric traction. The prevailing primary energy source of the railway electric power supply is coal, but the DB uses also furnace gas, nuclear energy and hydroelectric power. The shave of mineral oil lies by about 5%. The public utilities deliver about 15%. The dispersed situation of the power stations and converter stations over the whole supply area offers the advantage of short transport distances. Therefore the 110-kV-railway mains especially meets distribution demands. Very useful is the compound operation with the Austrian Federal Railways and the Swiss Federal Railways. (orig.) [de

  7. Modelling and simulation of railway cable systems

    Energy Technology Data Exchange (ETDEWEB)

    Teichelmann, G.; Schaub, M.; Simeon, B. [Technische Univ. Muenchen, Garching (Germany). Zentrum Mathematik M2

    2005-12-15

    Mathematical models and numerical methods for the computation of both static equilibria and dynamic oscillations of railroad catenaries are derived and analyzed. These cable systems form a complex network of string and beam elements and lead to coupled partial differential equations in space and time where constraints and corresponding Lagrange multipliers express the interaction between carrier, contact wire, and pantograph head. For computing static equilibria, three different algorithms are presented and compared, while the dynamic case is treated by a finite element method in space, combined with stabilized time integration of the resulting differential algebraic system. Simulation examples based on reference data from industry illustrate the potential of such computational tools. (orig.)

  8. From Heuristic to Mathematical Modeling of Drugs Dissolution Profiles: Application of Artificial Neural Networks and Genetic Programming

    Directory of Open Access Journals (Sweden)

    Aleksander Mendyk

    2015-01-01

    Full Text Available The purpose of this work was to develop a mathematical model of the drug dissolution (Q from the solid lipid extrudates based on the empirical approach. Artificial neural networks (ANNs and genetic programming (GP tools were used. Sensitivity analysis of ANNs provided reduction of the original input vector. GP allowed creation of the mathematical equation in two major approaches: (1 direct modeling of Q versus extrudate diameter (d and the time variable (t and (2 indirect modeling through Weibull equation. ANNs provided also information about minimum achievable generalization error and the way to enhance the original dataset used for adjustment of the equations’ parameters. Two inputs were found important for the drug dissolution: d and t. The extrudates length (L was found not important. Both GP modeling approaches allowed creation of relatively simple equations with their predictive performance comparable to the ANNs (root mean squared error (RMSE from 2.19 to 2.33. The direct mode of GP modeling of Q versus d and t resulted in the most robust model. The idea of how to combine ANNs and GP in order to escape ANNs’ black-box drawback without losing their superior predictive performance was demonstrated. Open Source software was used to deliver the state-of-the-art models and modeling strategies.

  9. Logistic system as an essential element of modern organization of railway passenger traffic

    Directory of Open Access Journals (Sweden)

    O.A. Khodoskina

    2012-04-01

    Full Text Available The role and place of passenger transport services in the modern structure of rail transportation is considered. The need for approach to rail passenger transport as a logistics system, which is characterized by a set of parameters corresponding to the concept of logistics system in general and taking into account the peculiarities of railway passenger transportation is determined. The features of formation of such a system, taking into account the generally accepted theoretical approach and the specifics of rail transport are also presented. The concept of logistic system for railway vehicles is given; its overall structure is reviewed. The structure of the particular transport is defined by rail freight and in passenger traffic. Is an example of a mathematical model of the logistics system of rail passenger services on the basis of sets of incoming and outgoing parameters is determined. The structure of technologic process for goods and passenger transportation by rail from the perspective of logistics is characterized.

  10. An Evaluation Model for Tailings Storage Facilities Using Improved Neural Networks and Fuzzy Mathematics

    Directory of Open Access Journals (Sweden)

    Sen Tian

    2014-01-01

    Full Text Available With the development of mine industry, tailings storage facility (TSF, as the important facility of mining, has attracted increasing attention for its safety problems. However, the problems of low accuracy and slow operation rate often occur in current TSF safety evaluation models. This paper establishes a reasonable TSF safety evaluation index system and puts forward a new TSF safety evaluation model by combining the theories for the analytic hierarchy process (AHP and improved back-propagation (BP neural network algorithm. The varying proportions of cross validation were calculated, demonstrating that this method has better evaluation performance with higher learning efficiency and faster convergence speed and avoids the oscillation in the training process in traditional BP neural network method and other primary neural network methods. The entire analysis shows the combination of the two methods increases the accuracy and reliability of the safety evaluation, and it can be well applied in the TSF safety evaluation.

  11. Existing Noise Level at Railway Stations in Malaysia

    Directory of Open Access Journals (Sweden)

    Shahidan Shahiron

    2017-01-01

    Full Text Available Railway transportation known as one of the most environmental friendly transportation mode. However, the significance problems of railway transportation are noise pollution and negatively impact the wellbeing of the whole community. Unfortunately, there has been lack of public awareness about the noise level produce by the railway transportation in Malaysia. This study investigates the noise level produced by railway transportation in Malaysia specifically by Keretapi Tanah Melayu Berhad (KTMB. Methods of collecting existing noise level at railway stations in Malaysia are briefly discussed in this study. The finding indicates that the noise level produced by the railway transportation in Malaysia which is by KTMB is considered as dangerous to human being and also exceed the noise limit that has been assigned by Department of Environment Ministry of Natural Resources and Environment of Malaysia. A better noise barrier and improved material should be developed to mitigate the existing noise level produced by railway transportations in Malaysia.

  12. Railway safety climate: a study on organizational development.

    Science.gov (United States)

    Cheng, Yung-Hsiang

    2017-09-07

    The safety climate of an organization is considered a leading indicator of potential risk for railway organizations. This study adopts the perceptual measurement-individual attribute approach to investigate the safety climate of a railway organization. The railway safety climate attributes are evaluated from the perspective of railway system staff. We identify four safety climate dimensions from exploratory factor analysis, namely safety communication, safety training, safety management and subjectively evaluated safety performance. Analytical results indicate that the safety climate differs at vertical and horizontal organizational levels. This study contributes to the literature by providing empirical evidence of the multilevel safety climate in a railway organization, presents possible causes of the differences under various cultural contexts and differentiates between safety climate scales for diverse workgroups within the railway organization. This information can be used to improve the safety sustainability of railway organizations and to conduct safety supervisions for the government.

  13. PULSim: User-Based Adaptable Simulation Tool for Railway Planning and Operations

    Directory of Open Access Journals (Sweden)

    Yong Cui

    2018-01-01

    Full Text Available Simulation methods are widely used in the field of railway planning and operations. Currently, several commercial software tools are available that not only provide functionality for railway simulation but also enable further evaluation and optimisation of the network for scheduling, dispatching, and capacity research. However, the various tools are all lacking with respect to the standards they utilise as well as their published interfaces. For an end-user, the basic mechanism and the assumptions built into a simulation tool are unknown, which means that the true potential of these software tools is limited. One of the most critical issues is the lack of the ability of users to define a sophisticated workflow, integrated in several rounds of simulation with adjustable parameters and settings. This paper develops and describes a user-based, customisable platform. As the preconditions of the platform, the design aspects for modelling the components of a railway system and building the workflow of railway simulation are elaborated in detail. Based on the model and the workflow, an integrated simulation platform with open interfaces is developed. Users and researchers gain the ability to rapidly develop their own algorithms, supported by the tailored simulation process in a flexible manner. The productivity of using simulation tools for further evaluation and optimisation will be significantly improved through the user-adaptable open interfaces.

  14. Mathematical modeling

    CERN Document Server

    Eck, Christof; Knabner, Peter

    2017-01-01

    Mathematical models are the decisive tool to explain and predict phenomena in the natural and engineering sciences. With this book readers will learn to derive mathematical models which help to understand real world phenomena. At the same time a wealth of important examples for the abstract concepts treated in the curriculum of mathematics degrees are given. An essential feature of this book is that mathematical structures are used as an ordering principle and not the fields of application. Methods from linear algebra, analysis and the theory of ordinary and partial differential equations are thoroughly introduced and applied in the modeling process. Examples of applications in the fields electrical networks, chemical reaction dynamics, population dynamics, fluid dynamics, elasticity theory and crystal growth are treated comprehensively.

  15. On-Site Measurements for Voltage Unbalance Studies Associated with the AC Railway Operation

    DEFF Research Database (Denmark)

    Stamatopoulos, Athanasios; Silva, Filipe Miguel Faria da; Bak, Claus Leth

    2017-01-01

    unbalance with regards to traction loads has been augmented since the decision to expand the electric railway. Towards this direction, and on the occasion of a newly built electrified line, voltage unbalance measurements were carried out and are presented in this paper. The information from the extracted......On-site measurements in Electrical Power Systems can provide valuable information about the performance of the network and also, can be of great assistance to the validation and assessment of simulation models developed for power system studies. Lately, the noticeable increase of non......-conventional types of loads, such as the AC railway, has raised concerns regarding the secure operation of power transmission networks. This renders the monitoring and reporting of various aspects of system’s power quality even more necessary. For the Danish transmission grid, in particular, the relevance of voltage...

  16. The State of the Railways in SA

    African Journals Online (AJOL)

    the railways at many key points in Natal and the ... feking to a point just north of the Orange River on the Cape Main Line ... occupied to a point some three miles north of .... All photographs supplied by the Publicity and Travel Department of the.

  17. Electromagnetic compatibility in railways. Analysis and management

    Energy Technology Data Exchange (ETDEWEB)

    Ogunsola, Ade [Parsons Group International, Abu Dhabi (United Arab Emirates); Mariscotti, Andrea [Genoa Univ. (Italy)

    2013-07-01

    Recent research on electromagnetic compatibility (EMC) applied to railway systems. Focuses on the principles and application of EMC concepts to railway signalling, communications, power/traction and rolling stocks. Written by leading experts in the field. A railway is a complex distributed engineering system: the construction of a new railway or the modernisation of a existing one requires a deep understanding of the constitutive components and their interaction, inside the system itself and towards the outside world. The former covers the various subsystems (featuring a complex mix of high power sources, sensitive safety critical systems, intentional transmitters, etc.) and their interaction, including the specific functions and their relevance to safety. The latter represents all the additional possible external victims and sources of electromagnetic interaction. EMC thus starts from a comprehension of the emissions and immunity characteristics and the interactions between sources and victims, with a strong relationship to electromagnetics and to system modeling. On the other hand, the said functions are achieved and preserved and their relevance for safety is adequately handled, if the related requirements are well posed and managed throughout the process from the beginning. The link is represented by standards and their correct application, as a support to analysis, testing and demonstration.

  18. Design of railway obstacle detection prototype

    CSIR Research Space (South Africa)

    Xungu, Sipho A

    2017-11-01

    Full Text Available Survey Inspection Device (SID) test prototype platform to serve as an early warning system for locomotives and was to travel 2km ahead of a locomotive in order to inspect the railway for possible obstacles such as human beings, livestock and collisions...

  19. Monitoring of transition zones in railways

    NARCIS (Netherlands)

    Coelho, B.; Priest, J.; Holscher, P.; Powrie, W.

    2009-01-01

    Transitions between railway track on embankments or natural ground and fixed structures such as bridges and culverts often require substantial additional maintenance to preserve line, level and ride quality. This extra maintenance not only increases costs but also causes delays. Despite its

  20. Introducing gaming simulation in the Dutch railways

    NARCIS (Netherlands)

    Meijer, S.

    2012-01-01

    Innovation in the Dutch railways in the domain of capacity management and traffic control is increasingly difficult to implement because of the large interconnectedness of all processes and separation into different institutions and organizations. Meanwhile there is a push for quality improvements

  1. Disruption Management in Passenger Railway Transportation

    DEFF Research Database (Denmark)

    Groth, Julie Jespersen; Potthoff, Daniel; Clausen, Jens

    2009-01-01

    This paper deals with disruption management in passenger railway transportation. In the disruption management process, many actors belonging to different organizations play a role. In this paper we therefore describe the process itself and the roles of the different actors. Furthermore, we discuss...

  2. 20 CFR 202.13 - Electric railways.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Electric railways. 202.13 Section 202.13 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD RETIREMENT ACT EMPLOYERS UNDER... conclusion reached the question will be submitted to the Interstate Commerce Commission for determination...

  3. Performance communication of the Belgian railway

    NARCIS (Netherlands)

    Gelders, Dave; Verckens, Jan Pieter; Galetzka, Mirjam; Seydel, E.R.

    2007-01-01

    Purpose – The purpose of this paper is to provide an insight into performance communication from an important public service, i.e. the Belgian Railway, towards its employees (internal) and stakeholders (external). Design/methodology/approach – A qualitative research approach was taken in the form of

  4. Efficient Circulation of Railway Rolling Stock

    NARCIS (Netherlands)

    Alfieri, A.; Groot, R.; Kroon, L.G.; Schrijver, A.

    2006-01-01

    Railway rolling stock (locomotives, carriages, and train units) is one of the most significant cost sources for operatorsof passenger trains, both public and private. Rolling stock costsare due to material acquisition, power supply, and material maintenance. The efficient circulation of rolling

  5. Efficient Circulation of Railway Rolling Stock

    NARCIS (Netherlands)

    A. Alfieri (Arianna); R. Groot (Rutger); L.G. Kroon (Leo); A. Schrijver (Lex)

    2002-01-01

    textabstractRailway rolling stock (locomotives, carriages, and train units) is one of the most significant cost sources for operatorsof passenger trains, both public and private. Rolling stock costsare due to material acquisition, power supply, and material maintenance. The efficient circulation of

  6. Creating Intelligent Computer Workstation of a Freight Officer in a Single Information Space of Railway Transport: Synergetic Approach

    Science.gov (United States)

    Malybaev, Saken K.; Malaybaev, Nurlan S.; Isina, Botakoz M.; Kenzhekeeva, Akbope R.; Khuangan, Nurbol

    2016-01-01

    The article presents the results of researches aimed at the creation of automated workplaces for railway transport specialists with the help of intelligent information systems. The analysis of tendencies of information technologies development in the transport network was conducted. It was determined that the most effective approach is to create…

  7. Synchrotron X-ray measurement of residual strain within the nose of a worn manganese steel railway crossing

    DEFF Research Database (Denmark)

    Dhar, S.; Zhang, Y.; Xu, Ruichao

    2017-01-01

    Switches and crossings are an integral part of any railway network. Plastic deformation associated with wear and rolling contact fatigue due to repeated passage of trains cause severe damage leading to the formation of surface and sub-surface cracks which ultimately may result in rail failure. Kn...

  8. THE ANALISYS OF RAILWAY MULTI MOTORS ELECTRICAL DRIVE DYNAMIC

    Directory of Open Access Journals (Sweden)

    V. I. Khilmon

    2015-01-01

    Full Text Available The importance of multi motors electrical traction drive dynamic analysis is denoted by its large application in electrical driving railway vehicles. In this paper an analysis is presented for two inducton motors traction drive with frequency inverter, vector control, and speed sensors of each electrical drive. The goal of this work is the analysis of two induction motors electrical drive, taking into account parametric perturbations and also a limited moment of wheel-rail adhesion, by laboratory study and simulation. Because of difference between motor’s parameters, it is necessary for parallel work to select motors with identical resistances and inductive winding. For this purpose the parametric identification method was used for each electrical drive, and also for two parallel motors. The result of identification was used in control setting.The  slippage  of  the  traction  drives  is  difficult  to  reproduce  in  laboratory;  therefore a mathematical modeling and simulation of mechanical part with a traction force restriction, specific for railway transport, were carried out. The suggested simulation is built with account of elastic deformations in kinetic chain, transforming traction force. The model permits to study a dynamic system in various circumstances.The results of laboratory investigations and simulation of dynamic regimes for two motor electrical drives are presented in this article. The results of analysis show, that a minimal difference between any parameters of two motors, parallel connected to convertor, is important for the slippage stability.

  9. STIMULATION METHODS IMPROVEMENT OF EXIT ROUTE ON RAILWAY TRANSPORT

    Directory of Open Access Journals (Sweden)

    A. I. Verlan

    2014-01-01

    Full Text Available Purpose. The purpose of the article is to assess the costs, which are redistributed in the system «shipper−railroad−consignee» during routing of rail transportation and the development of tariff simulation methods of shippers to the exit routes formation. Methodology. Using economic and mathematical analysis the distribution of costs among the various participants of transportation process during the exit routes formation is investigated in the article. Findings. For implementation of the tariff simulation methods of exit routes and retention of the existing tariff structure it is proposed to provide in the «Tariff catalogue for freight transportation by railway transport of Ukraine» the discount, differentiated from haulage distance. A new method for determining the fees amount for cars supply and removal on approach tracks by train locomotives was also offered. Originality. As a result of the research a new method for determination of the exit rout efficiency that, unlike the existing one, takes into account the various interests of the individual participants in the transportation process was proposed. The dependence of the correction factors to the tariff for freight transportation in their own cars by direct exit routes from distance haulage was obtained. Implementation of these coefficients provides an approximation of railway tariffs to the traffic handling costs. A method for determination the rate of fees for cars supply and removal on approach tracks by train locomotives was offered. Practical value. InUkraine creation of the tariff discounts system for freight transportation by exit routes consistent with international practice and allows bringing the tariff to the real traffic handling cost. This change on the one hand will provide stimulation for private capital investments in infrastructure development and shunting means of approach tracks, on the other – it will fix the shippers to the railroads and stop their outflow

  10. Mathematical Approaches to WMD Defense and Vulnerability Assessments of Dynamic Networks

    Science.gov (United States)

    2016-07-01

    be reversed at a time. Continuing with the constraints of the problem , in (28) we enforce a capacity at every intersection of the transportation ...world telecommunication, transportation , and power grids. • Develop compact formulations for “generalized network interdiction problems ,” in which...In this problem , attacks are made at points in (Euclidean) space. Damage is inflicted on each arc by reducing its capacity as a function of the

  11. Using Improved Entropy-Cloud Model to Select High-Speed Railway Express Freight Train Service Sites

    Directory of Open Access Journals (Sweden)

    Wencheng Huang

    2017-01-01

    Full Text Available High-speed railway (HSR express freight train service sites selection is critical to the development of China’s Third Party Logistics market. In this paper, we formulate an improved entropy-cloud model based approach to solve the HSR express sites selection problem for the first time. The basic data of the indicators, for example, existing railway network conditions, traffic environment, express freight market demand, and policy, will be used as the inputs. We apply improved entropy method to obtain each subindicator’s weight. The cloud model will be used to select and classify each station under evaluation.

  12. Railways: Gateways Between East and West in Europe

    Directory of Open Access Journals (Sweden)

    Hansjorg Kuster

    2003-07-01

    Full Text Available Railways have connected various far-flung parts of Europefor much of the last two centuries. Recent years, however, haveseen a decline in direct international connections. This is not somuch due to political developments (the Iron Curtain ceased toexist during the period in question, but rather technical advancesthat have resulted in the development of high-speed networksspecific to various countries. Problems associated withthe use of different gauges, and also electrical and sophisticatedelectronic systems in individual European countries have resultedin high-speed trains being confined mainly to individualstates. During the next years, it is highly desirable to re-establishan international European train or Transrapid network to avoidroad and air-traffic chaos as European integration proceedswith the planned eastwards expansion of the European Union.

  13. The Issues of Track Maintenance Management in Indonesia (Based on Study of the British Railways

    Directory of Open Access Journals (Sweden)

    Tetria Yunik Dewi Pamungkas

    2017-01-01

    Full Text Available It is believed that there is merit in researching how the management of track maintenance is organized in the United Kingdom, in particular by Network Rail, and then evaluating how this can be applied to the benefit of Indonesian Railways. The purpose of this research was expected to provide recommendations for management improvement of track maintenance by researching the track maintenance management system in Network Rail. This research study is based on secondary data. The analysis was conducted by using comparison method which compares the British Railways management and Indonesia railway management related to track maintenance management. The track maintenance management system was studied by using Network Rail. The results were compared with track maintenance management system in Indonesia. The comparison will provide the data differences that evaluated so the problem can be identified. The final result of this analysis was the identification of problems and improvisation that can be done for the development of track maintenance management in Indonesia. Several management issues have been mapped to several groups: finance management, structure organization, and asset management. From the problems that have been mapped, some improvements are recommended as monopolist authority restriction, maintenance system contract extension, re-structuring organization hierarchy, business plan consideration, track monitoring strategy arrangement, and condition based maintenance strategy adoption.

  14. A mathematical analysis of the effects of Hebbian learning rules on the dynamics and structure of discrete-time random recurrent neural networks.

    Science.gov (United States)

    Siri, Benoît; Berry, Hugues; Cessac, Bruno; Delord, Bruno; Quoy, Mathias

    2008-12-01

    We present a mathematical analysis of the effects of Hebbian learning in random recurrent neural networks, with a generic Hebbian learning rule, including passive forgetting and different timescales, for neuronal activity and learning dynamics. Previous numerical work has reported that Hebbian learning drives the system from chaos to a steady state through a sequence of bifurcations. Here, we interpret these results mathematically and show that these effects, involving a complex coupling between neuronal dynamics and synaptic graph structure, can be analyzed using Jacobian matrices, which introduce both a structural and a dynamical point of view on neural network evolution. Furthermore, we show that sensitivity to a learned pattern is maximal when the largest Lyapunov exponent is close to 0. We discuss how neural networks may take advantage of this regime of high functional interest.

  15. Transformation of power generated in railways dispossession belt by solar energy

    Directory of Open Access Journals (Sweden)

    Ю. П. Гончаров

    2015-11-01

    Full Text Available The arising deficiency of traditional energy sources necessitates the use of renewable energetics. One of the advantages of the sources of renewable energy is the possibility of constructing a system of distributed generation. For conditions of Ukraine distributed generators placed along the existing facilities with a linear arrangement are the most promising. The railways with their land dispossession belt can be used for these purposes. The distributed generation systems in railway transport can also be used in the regions with an unstable electricity supply, improving power quality, feeding autonomous objects of railway infrastructure. Distributed generation equipment can be used to reduce bias and voltage unbalance in power systems of stationary consumers. The projects using solar energy for the needs of railway transport show their high adaptability and efficiency. The article is devoted to the development of the DC power supply system. The railway contains additional longitudinal DC line with an operating voltage of about 1 kV and a system of semiconductor converters for connecting the longitudinal line and the main contact system through matching modules. Sequential positioning of the longitudinal line and the photo module is consistent with their properties as a current source that is proportional to the intensity of solar radiation. Semiconductor converters should be made using the same "a forward" topology, which simplifies the electrical circuit. Amorphous magnetic alloy is the most promising material for the existing isolation transformers in the system. Proper value of the operating frequency of the AC intermediaries is about 1 kHz. Traction power supply system with distributed PV generation, discussed in this article, will make it possible to put into practice the concept of intellectual traction power supply, optimizing the process of electric energy consumption in the traction network

  16. Develop railway engineering modules in UTK civil engineering undergraduate and graduate courses.

    Science.gov (United States)

    2015-05-31

    The importance of railway transport has long been recognized. However, no railway : engineering courses have been provided in the UTK civil engineering curricula. The : objective of this education project is to develop some railway engineering module...

  17. Mathematical Modeling and Evaluation of Human Motions in Physical Therapy Using Mixture Density Neural Networks.

    Science.gov (United States)

    Vakanski, A; Ferguson, J M; Lee, S

    2016-12-01

    The objective of the proposed research is to develop a methodology for modeling and evaluation of human motions, which will potentially benefit patients undertaking a physical rehabilitation therapy (e.g., following a stroke or due to other medical conditions). The ultimate aim is to allow patients to perform home-based rehabilitation exercises using a sensory system for capturing the motions, where an algorithm will retrieve the trajectories of a patient's exercises, will perform data analysis by comparing the performed motions to a reference model of prescribed motions, and will send the analysis results to the patient's physician with recommendations for improvement. The modeling approach employs an artificial neural network, consisting of layers of recurrent neuron units and layers of neuron units for estimating a mixture density function over the spatio-temporal dependencies within the human motion sequences. Input data are sequences of motions related to a prescribed exercise by a physiotherapist to a patient, and recorded with a motion capture system. An autoencoder subnet is employed for reducing the dimensionality of captured sequences of human motions, complemented with a mixture density subnet for probabilistic modeling of the motion data using a mixture of Gaussian distributions. The proposed neural network architecture produced a model for sets of human motions represented with a mixture of Gaussian density functions. The mean log-likelihood of observed sequences was employed as a performance metric in evaluating the consistency of a subject's performance relative to the reference dataset of motions. A publically available dataset of human motions captured with Microsoft Kinect was used for validation of the proposed method. The article presents a novel approach for modeling and evaluation of human motions with a potential application in home-based physical therapy and rehabilitation. The described approach employs the recent progress in the field of

  18. Model of traffic access mode and railway station choice of suburban railway system in Slovenia

    Directory of Open Access Journals (Sweden)

    Gregor RAK

    2014-12-01

    Full Text Available This article presents the establishment of a model of understanding the access mode and railway station choice of Slovenian passengers. Therefore, a model has been designed to predict the determination of existing decision making preferences of railway users about the access mode and railway station choice with a stated preference survey and face to face method. The target group in the survey were railway passengers in the suburban environment that use the rail for work and school purposes. The total number of respondents was 412. The survey showed that most passengers access the railway station with car (60,2%, by foot (26,2%, with public transport (bus – 8,3% and with bike (5,3%. Average distance to the station is 4,9 km, average time of access is 10,5 min. Upon exit most passengers walk to the final destination (84,5%, use the public transport (bus – 14,1%, car (1,2% or bike (0,2%. Average time from exit of the train to final destination is 13,1 min, average distance is 1,58 km.

  19. Real-Time Track Reallocation for Emergency Incidents at Large Railway Stations

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2015-01-01

    Full Text Available After track capacity breakdowns at a railway station, train dispatchers need to generate appropriate track reallocation plans to recover the impacted train schedule and minimize the expected total train delay time under stochastic scenarios. This paper focuses on the real-time track reallocation problem when tracks break down at large railway stations. To represent these cases, virtual trains are introduced and activated to occupy the accident tracks. A mathematical programming model is developed, which aims at minimizing the total occupation time of station bottleneck sections to avoid train delays. In addition, a hybrid algorithm between the genetic algorithm and the simulated annealing algorithm is designed. The case study from the Baoji railway station in China verifies the efficiency of the proposed model and the algorithm. Numerical results indicate that, during a daily and shift transport plan from 8:00 to 8:30, if five tracks break down simultaneously, this will disturb train schedules (result in train arrival and departure delays.

  20. The factorial structure of professionally-applied physical fitness of students of railway specialties

    Directory of Open Access Journals (Sweden)

    Anzhelika Yefremova

    2017-02-01

    Full Text Available Purpose: to define the factorial structure of professionally-applied physical fitness of students – future electrical engineers of railway transport. Material & Methods: analysis and synthesis of references, questioning, anthropometry, testing, functional tests, and methods of mathematical statistics (the factorial analysis with application of the computer program "SPSS 17.0". 50 students (young men of Ukrainian state railway university participated in the research. Results: the ratio of means of physical culture which are expedient to use for the optimization of professionally-applied physical training of future specialists of the railway branch is defined. Conclusions: the factorial analysis allowed to distribute means of physical education as follows: physical exercises which are directed to the increase in physical working capacity and overall physical fitness – about 40%; exercises on the development of power qualities – 25%; exercises on the development of high-speed and power endurance – 15%; means which are allocated for the improvement of functions of attention and kinetic sensitivity – 10%; exercises which are directed to the increase in special working capacity – 10%.

  1. Salmonella outbreak among railway and airline passengers.

    Science.gov (United States)

    Hatakka, M

    1992-01-01

    A widespread outbreak by Salmonella infantis, infecting a total of 226 people, occurred in Finland at the beginning of August 1986. Of those infected, 107 were railway passengers, 91 were airline passengers and 28 were employed in a food processing establishment. The outbreak among the railway passengers was caused by egg sandwiches, the airline passengers were infected by a meal served on board and the catering employees by the breakfast served in the establishment. The outbreak was caused by food prepared in the establishment's kitchen. The employees' breakfasts had probably been contaminated by an employee who was a symptom-free Salmonella infantis carrier, and a number of the employees subsequently became infected, leading to widespread contamination of the food prepared in the establishment. The spread of the outbreak was further influenced by a heatwave at the time and by shortcomings in the cold storage facilities. The kitchen's hygiene supervision and the quality control of its output were reorganized after the outbreak.

  2. Efficiency and Robustness in Railway Operations

    DEFF Research Database (Denmark)

    Bull, Simon Henry; Pisinger, David

    reliability. Offering these services presents a challenging sequence of planning problems for operators. These range from problems considered on a daily basis to planning for years in the future, with different problems interacting and influencing each other. Operations research methods can be used...... to effectively model, investigate, and solve railway planning problems. Despite advances in computational power these large problems are still challenging to solve, especially as more modelling detail is sought. Within a Danish context this thesis seeks to apply operations research methods to different planning...... problems beyond past approaches, and where applicable, investigate solution methods that place more focus on the passenger and passenger experience. To cater to the growing demand for rail transport, and compete with different modes of transport, Danish railway operators must offer a consistent, reliable...

  3. A Survey on Robustness in Railway Planning

    DEFF Research Database (Denmark)

    Lusby, Richard Martin; Larsen, Jesper; Bull, Simon Henry

    2018-01-01

    Planning problems in passenger railway range from long term strategic decision making to the detailed planning of operations.Operations research methods have played an increasing role in this planning process. However, recently more attention has been given to considerations of robustness...... in the quality of solutions to individual planning problems, and of operations in general. Robustness in general is the capacity for some system to absorb or resist changes. In the context of railway robustness it is often taken to be the capacity for operations to continue at some level when faced...... with a disruption such as delay or failure. This has resulted in more attention given to the inclusion of robustness measures and objectives in individual planning problems, and to the providing of tools to ensure operations continue under disrupted situations. In this paper we survey the literature on robustness...

  4. Electromagnetic Compatibility in Railways Analysis and Management

    CERN Document Server

    Ogunsola, Ade

    2013-01-01

    A railway is a complex distributed engineering system: the construction of a new railway or the modernisation of a existing one requires a deep understanding of the constitutive components and their interaction, inside the system itself and towards the outside world. The former covers the various subsystems (featuring a complex mix of high power sources, sensitive safety critical systems, intentional transmitters, etc.) and their interaction, including the specific functions and their relevance to safety. The latter represents all the additional possible external victims and sources of electromagnetic interaction. EMC thus starts from a comprehension of the emissions and immunity characteristics and the interactions between sources and victims, with a strong relationship to electromagnetics and to system modeling. On the other hand, the said functions are achieved and preserved and their relevance for safety is adequately handled, if the related requirements are well posed and managed throughout the process f...

  5. The noise factor in railway locomotives.

    Science.gov (United States)

    Rotter, T

    1982-09-01

    This article concerns the problem of acoustic work conditions on railway locomotives. The objective results of sonometric surveys in locomotive cabins are compared with subject data received from locomotive crews obtained by means of a specific questionnaire 'The Subjective Estimation of Noise'. The analysis touched 9 type of locomotives; steam, diesel and electric engines. We asked drivers of different age groups and with varying lengths of professional service for their opinions The aim of the investigation was to determine the following points: 1. to analyse the drivers' subjective estimation of the noise in the locomotive cabins; 2. to define length of time for which the driver remains under the influence of the noise after finishing work; 3. to investigate the question of perception and understanding of sounds and vocal signals used in the locomotive. These problems are a small part of the general plan to improve work conditions on the Polish National Railways.

  6. Liberalisation in network based industries. An economic analysis by case studies of railway, telecommunication and energy utilities; Liberalisierung von Netzindustrien. Eine oekonomische Analyse am Beispiel der Eisenbahn, der Telekommunikation und der Leitungsgebundenen Energieversorgung

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, A.

    2006-07-01

    The liberalisation of network based industries represents an economic problem, which raises on the one hand a multiplicity of theoretically unresolved questions and for which exist now on the other hand experiences in economic policy in Germany. The causes of the economic problems are not only to be found thereby in certain industry characteristics of the network based industries, but also in a missed special treatment of the network based economic sectors in the past by the economic policy. However, competition pushes in network based industries at borders, because the infrastructure necessary for the production of network based services typically represents an non-open to attack, natural monopoly in the hand of an established, vertically integrated supplier. From it extensive possibilities for the discrimination of competitors result, the competition political action need draw. It applies to analyze these in the available work and to discuss alternative solutions of the discrimination problem. (orig.)

  7. APPRAISAL OF USED WOODEN RAILWAY SLEEPER

    Directory of Open Access Journals (Sweden)

    SITI HAWA HAMZAH

    2008-12-01

    Full Text Available Replacement of wooden sleepers to prestressed concrete sleepers has marked as advancement in the railway sleepers industry in Malaysia. Despite superiority of these man-made composite sleepers, wooden sleepers still lead in terms of track performance qualities in particular on its natural elasticity. An initiative to investigate the degree of degradation of used wooden sleepers and the possibility of reusing them on low capacity railway track in Malaysia as a means of reducing the overall track rehabilitation cost was undertaken. Used wooden sleepers were tested according to Australian Standard, Railway Track Material, Prestressed Concrete Sleepers (AS 1085:14:2003 on Rail Seat Vertical Load Test and Centre Positive Bending Moment Test. Six wooden sleeper samples were tested under the static load until failure. Benchmarking was carried on high strength prestressed concrete sleeper, tested according to AS 1085:14:2003: Rail Seat - Positive Moment Test. The results obtained showed the maximum load that the used wooden sleepers can carry surpassed the design load of KTMB specifications and it is about 58% of high strength prestressed concrete sleeper.The maximum deflection produced by all used wooden sleepers is 20 mm showing that the sleepers maintained their elastic behaviour. Modulus of Elasticity ranging from 21 to 27 kN/mm2 of which within the standard value, indicating weathering process does not so much affect their stiffness. Most sleepers showed crack patterns propagated in the longitudinal direction. Toughness value is almost one half of the high strength prestressed concrete sleeper. This study indicates that there is a potential of reusing the wooden sleepers for light loading of the railway track. Hence, an extensive study is recommended to be carried out under fatigue loading condition.

  8. Nonlinear Dynamic Characteristics of the Railway Vehicle

    Science.gov (United States)

    Uyulan, Çağlar; Gokasan, Metin

    2017-06-01

    The nonlinear dynamic characteristics of a railway vehicle are checked into thoroughly by applying two different wheel-rail contact model: a heuristic nonlinear friction creepage model derived by using Kalker 's theory and Polach model including dead-zone clearance. This two models are matched with the quasi-static form of the LuGre model to obtain more realistic wheel-rail contact model. LuGre model parameters are determined using nonlinear optimization method, which it's objective is to minimize the error between the output of the Polach and Kalker model and quasi-static LuGre model for specific operating conditions. The symmetric/asymmetric bifurcation attitude and stable/unstable motion of the railway vehicle in the presence of nonlinearities which are yaw damping forces in the longitudinal suspension system are analyzed in great detail by changing the vehicle speed. Phase portraits of the lateral displacement of the leading wheelset of the railway vehicle are drawn below and on the critical speeds, where sub-critical Hopf bifurcation take place, for two wheel-rail contact model. Asymmetric periodic motions have been observed during the simulation in the lateral displacement of the wheelset under different vehicle speed range. The coexistence of multiple steady states cause bounces in the amplitude of vibrations, resulting instability problems of the railway vehicle. By using Lyapunov's indirect method, the critical hunting speeds are calculated with respect to the radius of the curved track parameter changes. Hunting, which is defined as the oscillation of the lateral displacement of wheelset with a large domain, is described by a limit cycle-type oscillation nature. The evaluated accuracy of the LuGre model adopted from Kalker's model results for prediction of critical speed is higher than the results of the LuGre model adopted from Polach's model. From the results of the analysis, the critical hunting speed must be resolved by investigating the track tests

  9. NDT of railway components using induction thermography

    Science.gov (United States)

    Netzelmann, U.; Walle, G.; Ehlen, A.; Lugin, S.; Finckbohner, M.; Bessert, S.

    2016-02-01

    Induction or eddy current thermography is used to detect surface cracks in ferritic steel. The technique is applied to detect surface cracks in rails from a moving test car. Cracks were detected at a train speed between 2 and 15 km/h. An automated demonstrator system for testing railway wheels after production is described. While the wheel is rotated, a robot guides the detection unit consisting of inductor and infrared camera over the surface.

  10. Fatigue lifetime estimation of railway axles

    Czech Academy of Sciences Publication Activity Database

    Náhlík, Luboš; Pokorný, Pavel; Ševčík, Martin; Fajkoš, R.; Matušek, P.; Hutař, Pavel

    2017-01-01

    Roč. 73, MAR (2017), s. 139-157 ISSN 1350-6307 R&D Projects: GA MŠk LM2015069; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : Residual fatigue lifetime * Railway axle * Variable amplitude loading * Fatigue crack propagation * Damage tolerance methodology Subject RIV: JL - Materials Fatigue, Friction Mechanics OBOR OECD: Audio engineering, reliability analysis Impact factor: 1.676, year: 2016

  11. Mathematical Modeling of Air Flowfield at Urban Environment: the Case of Road Network at the Historical Centre of Kifissia's Municipality

    Science.gov (United States)

    Papakonstantinou, K.; Belias, C.

    2008-09-01

    The present paper refers to the numerical analysis of air flowfield at urban environments and the conducting thermal comfort after the evaluation of the examined space using CFD methods, taking into account bioclimatic principles at the architectural design. More specially, the paper draws attention to the physical procedures governing air movement at an urban environment (a road network) at Kifissia (a Municipality of north Athens), trying to form them in such way that will lead to the thermal comfort of the area's users. The study presents a mathematical model, implemented in a general computer code that can provide detailed information on velocity, prevailing in three-dimensional spaces of any geometrical complexity. Turbulent flow is simulated and buoyancy effects are taken into account. This simulation procedure is intended to contribute to the effort towards designing urban environments, using thermal comfort criteria at the bioclimatic design. A computer model of this kind will provide the architects or the environmental engineers with powerful and economical means of evaluating alternative spaces' designs.

  12. A comparative study of different transformer connections for railway power supply- mitigation of voltage unbalance

    DEFF Research Database (Denmark)

    Firat, Gurkan; Yang, Guangya; Ali Hussain Al-Ali, Haider

    2015-01-01

    The railway represents a large power consumer that can cause uneven loading of the phases in the high voltage grid. These unbalanced loads supplied by the utility may lead to voltage unbalance problems in the system and thereby affects the other consumers connected to the same network. It is fact...... that, voltage unbalance appears mainly as a result of unbalanced currents at the points of common coupling drawn by unevenly distributed loads. Because of a significant amount of negative sequence current injected to the system, the power system components will suffer from consequent negative effects...... such as overheating, additional losses of lines and transformers, interference with communication systems etc. This paper presents a comparative study of some transformer connections which commonly used in railway supplying AC traction loads, for voltage unbalance mitigations. Simulations for comparison...

  13. Operating a railway system within a challenging environment: Economic history and experiences of Zimbabwe’s national railways

    OpenAIRE

    Charles Mbohwa

    2008-01-01

    This paper presents a historical background to the development of the railways in Zimbabwe and then discusses their current state. Besides being a landlocked country in Southern Africa, Zimbabwe has since 2000 been saddled with socio-economic and political challenges which have seen a decline in all economic indices, hence posing some challenges to its railways. This article discusses the challenges faced by the railways as a result of high inflation, unstable currency exchange rate, brain dr...

  14. Mathematics, anxiety, and the brain.

    Science.gov (United States)

    Moustafa, Ahmed A; Tindle, Richard; Ansari, Zaheda; Doyle, Margery J; Hewedi, Doaa H; Eissa, Abeer

    2017-05-24

    Given that achievement in learning mathematics at school correlates with work and social achievements, it is important to understand the cognitive processes underlying abilities to learn mathematics efficiently as well as reasons underlying the occurrence of mathematics anxiety (i.e. feelings of tension and fear upon facing mathematical problems or numbers) among certain individuals. Over the last two decades, many studies have shown that learning mathematical and numerical concepts relies on many cognitive processes, including working memory, spatial skills, and linguistic abilities. In this review, we discuss the relationship between mathematical learning and cognitive processes as well as the neural substrates underlying successful mathematical learning and problem solving. More importantly, we also discuss the relationship between these cognitive processes, mathematics anxiety, and mathematics learning disabilities (dyscalculia). Our review shows that mathematical cognition relies on a complex brain network, and dysfunction to different segments of this network leads to varying manifestations of mathematical learning disabilities.

  15. ISSUES OF ORGANIZING THE PASSENGER TRANSPORTATION ON US RAILWAYS

    Directory of Open Access Journals (Sweden)

    R. H. Korobiova

    2017-04-01

    Full Text Available Purpose. The paper focuses on a study of the US railway transport organization management during passenger transportation. Methodology. Studies were carried out on the basis of the analysis of literature sources and reporting data on passenger transportation in the USA. Findings. Negative trends in the work of the passenger complex of the Ukrainian railways are the slowdown in the volumes of transportation, the progressive aging of the rolling stock and the overall activity running at a loss for Ukrzaliznytsia. In this regard, the actual task for domestic rail transport is the implementation of industry reforms. Therefore, the paper presented the study of the experience of organizing the passenger transportation on US railways, whose peculiarity is the extremely high degree of competition between modes of transport. As a result of the conducted analysis for working conditions of the US and Ukrainian railways, the general conditions for the functioning of the railways in both countries connected with passenger transportation securing have been established. It was found that general condition for execution of railway passenger transportation for the United States and Ukraine is the subsidization of this activity and combined use of infrastructure for the freight and passengers’ transportations. In this connection, when developing approaches to reforming the passenger economy of Ukraine's railways, it is advisable to use the experience of the United States in assessing the social effectiveness of rail transport, the impact of passenger transportation on the conditions of freight trains handling, and combined use of railway infrastructure by freight and passenger companies. Originality. The author determined the general trends in the development of passenger railway transportation in the US and Ukraine. Practical value. The resulted methods of organizing the operation of the US railway passenger transportation complex can be adapted to solve

  16. A magneto rheological hybrid damper for railway vehicles suspensions

    Directory of Open Access Journals (Sweden)

    Gheorghe GHITA

    2012-09-01

    Full Text Available High speed railway vehicles features a specific lateral oscillation resulting from the coupled lateral displacement and yaw of the wheelset which leads to a sinusoid movement of the wheelset along the track, transferred to the entire vehicle. The amplitude of this oscillation is strongly dependant on vehicle’s velocity. Over a certain value, namely the critical speed, the instability phenomenon so-called hunting occurs. To raise the vehicle’s critical speed different designs of the suspension all leading to a much stiffer vehicle can be envisaged. Different simulations prove that a stiffer central suspension will decrease the passenger’s comfort in terms of lateral accelerations of the carboy. The authors propose a semi-active magneto rheological suspension to improve the vehicle’s comfort at high speeds. The suspension has as executive elements hybrid magneto rheological dampers operating under sequential control strategy type balance logic. Using an original mathematical model for the lateral dynamics of the vehicle the responses of the system with passive and semi-active suspensions are simulated. It is shown that the semi-active suspension can improve the vehicle performances.

  17. Geo mathematic tools for the design of a radioisotopes monitoring network in order to modelling the groundwater dynamics processes and hydrodynamic management

    International Nuclear Information System (INIS)

    Peralta, J.L.; Gil, R.; Leyva, D.; Molerio, L.F.; Pin, M.

    2004-01-01

    The present paper, shows the application of geo mathematic tools [Mangin,1981; Molerio,1997] for the design of a radioisotopes monitoring network in order to modelling the groundwater dynamics processes and hydrodynamic management of a Karstic Basin (Almendares-Vento watershed), which is very difficult to evaluate due to the physical-geographical, geologic and hydrogeological characteristics. The Almendares Vento watershed (AVW) is close to the Jaruco-Aguacate watershed, with a similar hydrogeologic and geologic structure, therefore similar result must be expected. In the AVW case is necessary to identify, with more precision, the water propagation limits of the stratified layers according to the waters transit times, recharges and dynamics aquifers, residence time, groundwater contamination and the groundwater-surface water interaction due to the dam placed on the basin. The paper allowed the identification of a monitoring points network, taking into account, between other statistical approaches, the good correlation, the high memory effect, etc. According to the analysis of the variances spectral, have been obtained and optimized the sampling frequency of the network points in the Basin. Besides, it have been identified the necessities to include the detailed evaluation of a specific point of the network in the hydrodynamic study (Vento watershed). In order to evaluate the optimization of the designed monitoring network, the geo mathematic study developed was compared with the results of the mathematical model AQUIMPE, the final result showed the validation of the obtained design. The results of the work allow the best monitoring of the parameters in order to determine the aquifer recharge, residence times, the vulnerability to the waters contamination and the groundwater-surface water interaction

  18. Performance of LTE in High Speed Railway Scenarios

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José

    2013-01-01

    GSM-Railways (GSM-R) is an obsolete mobile technology with a number of shortcomings in terms of capacity and capability. These shortcomings become a major issue for railways as GSM-R may limit the number of running trains in some areas and it cannot support advanced data services. Hence...

  19. The effects of 10 years Railway investment in Denmark

    DEFF Research Database (Denmark)

    Hansen, Sten A.

    1998-01-01

    The paper retrives the impacts of the last 10 years of investment in railway infrastructure in Denmark and ooncludes, that traveltimes and frequency is large unchanged during that period.......The paper retrives the impacts of the last 10 years of investment in railway infrastructure in Denmark and ooncludes, that traveltimes and frequency is large unchanged during that period....

  20. Formal Methods and Safety Certification: Challenges in the Railways Domain

    DEFF Research Database (Denmark)

    Fantechi, Alessandro; Ferrari, Alessio; Gnesi, Stefania

    2016-01-01

    The railway signalling sector has historically been a source of success stories about the adoption of formal methods in the certification of software safety of computer-based control equipment.......The railway signalling sector has historically been a source of success stories about the adoption of formal methods in the certification of software safety of computer-based control equipment....

  1. Seismic Performance of Multi-Span RC Railway Bridges

    DEFF Research Database (Denmark)

    Georgakis, Christos; Barrau, Xavier

    2008-01-01

    Presently, there is no clear method for determining the optimal railway bridge design for a particular ground type and expected seismic intensity. Four main types of RC bridge dominate the current multi-span railway bridge design trends – the Simply Supported Beam, Continuous Box-Girder (CBG), CBG...

  2. The Penarroya mining railway; El Ferrocaril minero de Penarroya

    Energy Technology Data Exchange (ETDEWEB)

    Grado Contreras, J. I. de

    2009-07-01

    The French Society Miniere et Metallurgique de Panarroya mining railway, 241 km long, was the second largest private narrow gauge railway in Spain. Located in the inland. linked the coal and galena mines with foundries and also with the national railroads grid, to transport the minerals to national and foreign markets. (Author)

  3. The Ginghai-Tibet railway and Tibet tourism: travelers' perspectives

    Science.gov (United States)

    Ming Ming Su; Geoffrey Wall

    2009-01-01

    The Qinghai-Tibet railway opened in July 2006 and boosted Tibetan tourism markedly by increasing the accessibility and affordability of travel from China to Tibet. This study evaluates the railway's impacts on tourists' travel decisions and experiences in Tibet. The relative importance of the train journey in comparison with the destination experience in...

  4. WAYS OF IMPROVEMENT RAILWAY TRANSPORT IN OVERPASS ECONOMIC CRISIS CONDITIONS

    Directory of Open Access Journals (Sweden)

    O. H. Deineka

    2010-05-01

    Full Text Available In the article a problem of adapting the railway transport to market requirements is presented and the ways of improving its competitiveness are investigated. Some measures and reserves of improving the operation efficiency for the railway transport are offered.

  5. The political economy of railway construction in Nigeria: the Bornu ...

    African Journals Online (AJOL)

    The political economy of railway construction in Nigeria: the Bornu railway extension. ... One key strategy employed was to side with the faction of the Nigerian petty bourgeoisie whose political, economic and class interests were in agreement with ... The 400-mile extension was eventually constructed and opened in 1964.

  6. Disruption Management of Rolling Stock in Passenger Railway Transportation

    NARCIS (Netherlands)

    L.K. Nielsen (Lars Kjaer); G. Maróti (Gábor)

    2009-01-01

    textabstractThis paper deals with real-time disruption management of rolling stock in passenger railway transportation. We present a generic framework for modeling disruptions in railway rolling stock schedules. The framework is presented as an online combinatorial decision problem where the

  7. Modeling thermal effects in braking systems of railway vehicles

    Directory of Open Access Journals (Sweden)

    Milošević Miloš S.

    2012-01-01

    Full Text Available The modeling of thermal effects has become increasingly important in product design in different transport means, road vehicles, airplanes, railway vehicles, and so forth. The thermal analysis is a very important stage in the study of braking systems, especially of railway vehicles, where it is necessary to brake huge masses, because the thermal load of a braked railway wheel prevails compared to other types of loads. In the braking phase, kinetic energy transforms into thermal energy resulting in intense heating and high temperature states of railway wheels. Thus induced thermal loads determine thermomechanical behavior of the structure of railway wheels. In cases of thermal overloads, which mainly occur as a result of long-term braking on down-grade railroads, the generation of stresses and deformations occurs, whose consequences are the appearance of cracks on the rim of a wheel and the final total wheel defect. The importance to precisely determine the temperature distribution caused by the transfer process of the heat generated during braking due to the friction on contact surfaces of the braking system makes it a challenging research task. Therefore, the thermal analysis of a block-braked solid railway wheel of a 444 class locomotive of the national railway operator Serbian Railways is processed in detail in this paper, using analytical and numerical modeling of thermal effects during long-term braking for maintaining a constant speed on a down-grade railroad.

  8. Developing a Service Improvement System for the National Dutch Railways

    NARCIS (Netherlands)

    Verhoef, Peter C.; Heijnsbroek, Martin; Bosma, Joost

    2017-01-01

    Customer satisfaction is essential for public and railway services, because firms in these industries have contracts with governments requiring them to achieve specific customer satisfaction targets. In this paper, we describe a National Dutch Railways project in which we identify the major

  9. Application of data clustering to railway delay pattern recognition

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Nielsen, Bo Friis; Nielsen, Otto Anker

    2018-01-01

    K-means clustering is employed to identify recurrent delay patterns on a high traffic railway line north of Copenhagen, Denmark. The clusters identify behavioral patterns in the very large (“big data”) data sets generated automatically and continuously by the railway signal system. The results re...

  10. Efficient Development and Verification of Safe Railway Control Software

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Peleska, Jan

    2013-01-01

    the monitoring process; hydraulic absorbers as dampers to dissipate the energy of oscillations in railway electric equipment; development of train fare calculation and adjustment systems using VDM++; efficient development and verification of safe railway control software; and evolution of the connectivity...

  11. Railway station structures designed for densely populated urban areas

    NARCIS (Netherlands)

    Vákár, L.I.; Snijder, H.H.

    2001-01-01

    Recently, the interest in public transit increased because of its contribution in solving the problem in mobility. This resulted in a worldwide need for building new railway stations and expanding existing ones. A railway station forms no longer a building on its own, but part of a larger complex.

  12. 77 FR 47922 - BNSF Railway Company-Trackage Rights Exemption-Northern Lines Railway, Inc.

    Science.gov (United States)

    2012-08-10

    ... includes: (a) Track 204 between 33rd Avenue North and Rice Junction, Minn.; and (b) Track 203 between milepost 0.0, at Rice Junction, and milepost 5.71, just west of the Highway I-94 overpass (the Lines). \\1....C.C. 605 (1978), as modified in Mendocino Coast Railway--Lease & Operate--California Western...

  13. Railway line capacity consumption of different railway signalling systems under scheduled and disturbed conditions

    NARCIS (Netherlands)

    Goverde, R.M.P.; Corman, F.; D'Ariano, A.

    2013-01-01

    This paper evaluates the capacity consumption on a Dutch railway line both under scheduled and disturbed traffic conditions. For the scheduled condition the standard UIC compression method is used, while the computation of capacity consumption under disturbed conditions requires multiple simulation

  14. Introductory discrete mathematics

    CERN Document Server

    Balakrishnan, V K

    2010-01-01

    This concise text offers an introduction to discrete mathematics for undergraduate students in computer science and mathematics. Mathematics educators consider it vital that their students be exposed to a course in discrete methods that introduces them to combinatorial mathematics and to algebraic and logical structures focusing on the interplay between computer science and mathematics. The present volume emphasizes combinatorics, graph theory with applications to some stand network optimization problems, and algorithms to solve these problems.Chapters 0-3 cover fundamental operations involv

  15. Maintenance management of railway infrastructures based on reliability analysis

    International Nuclear Information System (INIS)

    Macchi, Marco; Garetti, Marco; Centrone, Domenico; Fumagalli, Luca; Piero Pavirani, Gian

    2012-01-01

    Railway infrastructure maintenance plays a crucial role for rail transport. It aims at guaranteeing safety of operations and availability of railway tracks and related equipment for traffic regulation. Moreover, it is one major cost for rail transport operations. Thus, the increased competition in traffic market is asking for maintenance improvement, aiming at the reduction of maintenance expenditures while keeping the safety of operations. This issue is addressed by the methodology presented in the paper. The first step of the methodology consists of a family-based approach for the equipment reliability analysis; its purpose is the identification of families of railway items which can be given the same reliability targets. The second step builds the reliability model of the railway system for identifying the most critical items, given a required service level for the transportation system. The two methods have been implemented and tested in practical case studies, in the context of Rete Ferroviaria Italiana, the Italian public limited company for railway transportation.

  16. Passenger Perspectives in Railway Timetabling: A Literature Review

    DEFF Research Database (Denmark)

    Jensen, Jens Parbo; Nielsen, Otto Anker; Prato, Carlo Giacomo

    2016-01-01

    When looking at railway planning, a discrepancy exists between planners who focus on the train operations and publish fixed railway schedules, and passengers who look not only at the schedules but also at the entirety of their trip, from access to waiting to on-board travel and egress. Looking...... with fluctuating passenger demand. A key aspect is the robustness of railway timetables. Empirical evidence indicates that passengers give more importance to travel time certainty than travel time reductions, as passengers associate an inherent disutility with travel time uncertainty. This disutility may...... be broadly interpreted as an anxiety cost for the need for having contingency plans in case of disruptions, and may be looked at as the motivator for the need for delay-robust railway timetables. Interestingly, passenger-oriented optimisation studies considering robustness in railway planning typically limit...

  17. Wideband analysis of railway catenary line radiation and new applications of its unintentional emitted signals

    Science.gov (United States)

    Heddebaut, Marc; Deniau, Virginie; Rioult, Jean

    2018-06-01

    Generally, in railway networks, dissipated energy—and its consequences in terms of noise, ballast attrition, electromagnetic interference, etc—is considered a nuisance generated by this means of transport. Therefore, most studies are carried out with the aim of reducing it. This paper takes the opposite view and considers the particular case of the irreducible electromagnetic interference generated along an electrified line, in order to propose new applications beneficial to railway operations. At a selected representative location, wideband (ranging from 10 kHz to 1 GHz) electromagnetic field measurements are performed successively during, and not during, high speed train passages. We deduce two potential applications of these unintentional signals. At low frequency, the first proposal considers energy harvesting using the received electromagnetic interference as the source. This received energy can be converted and used to DC feed low consumption sensors to be installed along the railway infrastructure. These sensors participate in monitoring infrastructure health and in making it more resilient to internal and external stresses. At higher frequencies, for the second proposal, radiation from the catenary line and train pantograph is specifically examined at a carefully selected sub-band. The results are also studied following a time–frequency analysis, to introduce a new nondestructive inspection method of the sliding contact between the catenary line and the train pantograph. Ultimately, this technique could offer a new means of monitoring the health of both the catenary line and the pantograph.

  18. Enabling the usage of UML in the verification of railway systems: The DAM-rail approach

    International Nuclear Information System (INIS)

    Bernardi, S.; Flammini, F.; Marrone, S.; Mazzocca, N.; Merseguer, J.; Nardone, R.; Vittorini, V.

    2013-01-01

    The need for integration of model-based verification into industrial processes has produced several attempts to define Model-Driven solutions implementing a unifying approach to system development. A recent trend is to implement tool chains supporting the developer both in the design phase and V and V activities. In this Model-Driven context, specific domains require proper modelling approaches, especially for what concerns RAM (Reliability, Availability, Maintainability) analysis and fulfillment of international standards. This paper specifically addresses the definition of a Model-Driven approach for the evaluation of RAM attributes in railway applications to automatically generate formal models. For this aim we extend the MARTE-DAM UML profile with concepts related to maintenance aspects and service degradation, and show that the MARTE-DAM framework can be successfully specialized for the railway domain. Model transformations are then defined to generate Repairable Fault Tree and Bayesian Network models from MARTE-DAM specifications. The whole process is applied to the railway domain in two different availability studies

  19. The Accuracy Assessment of Determining the Axis of Railway Track Basing on the Satellite Surveying

    Science.gov (United States)

    Koc, Władysław; Specht, Cezary; Chrostowski, Piotr; Palikowska, Katarzyna

    2012-09-01

    In 2009, at the Gdansk University of Technology there have been carried out, for the first time, continuous satellite surveying of railway track by the use of the relative phase method based on geodesic active network ASG-EUPOS and NAVGEO service. Still continuing research works focused on the GNSS multi-receivers platform evaluation for projecting and stock-taking. In order to assess the accuracy of the railway track axis position, the values of deviations of transverse position XTE (Cross Track Error) were evaluated. In order to eliminate the influence of random measurement errors and to obtain the coordinates representing the actual shape of the track, the XTE variable was analyzed by signal analysis methods (Chebyshev low-pass filtering and fast Fourier transform). At the end the paper presents the module of the computer software SATTRACK which currently has been developing at the Gdansk University of Technology. The program serves visualization, assessment and design process of railway track, adapted to the technique of continuous satellite surveying. The module called TRACK STRAIGHT is designed to assess the straight sections. A description of its operation as well as examples of its functions has been presented.

  20. A Cloud-Computing-Based Data Placement Strategy in High-Speed Railway

    Directory of Open Access Journals (Sweden)

    Hanning Wang

    2012-01-01

    Full Text Available As an important component of China’s transportation data sharing system, high-speed railway data sharing is a typical application of data-intensive computing. Currently, most high-speed railway data is shared in cloud computing environment. Thus, there is an urgent need for an effective cloud-computing-based data placement strategy in high-speed railway. In this paper, a new data placement strategy named hierarchical structure data placement strategy is proposed. The proposed method combines the semidefinite programming algorithm with the dynamic interval mapping algorithm. The semi-definite programming algorithm is suitable for the placement of files with various replications, ensuring that different replications of a file are placed on different storage devices, while the dynamic interval mapping algorithm ensures better self-adaptability of the data storage system. A hierarchical data placement strategy is proposed for large-scale networks. In this paper, a new theoretical analysis is provided, which is put in comparison with several other previous data placement approaches, showing the efficacy of the new analysis in several experiments.

  1. Application of unconventional geoelectrical methods to the hydrogeological examination of the Mt. S. Croce rock formations (Umbria, Italy involved in a railway tunnel project

    Directory of Open Access Journals (Sweden)

    D. Patella

    1994-06-01

    Full Text Available he project of doubling and developing of the railway line Orte-Falconara, committed by the Italian State Railway Company to the COMAVI Consortium (Rome, Italy, envisaged building the Mt. S. Croce tunnel, about 3200 m long between the stations of Narni and Nera Montoro (Umbria, ltaly. During the last phase of the feasibility project, a geophysical research based on geoelectrical prospecting methods was carried out to complement other geognostic investigations with the following goals: a to outline the complex geotectonic model of the rock system, which will be affected by the new railway layout; b to gain information on the hydrogeologic features of the survey area, in relation to the existing geologic situation and the consequent effects on the digging conditions of the tunnel and on the operation conditions of the railway layout. The geophysical work was thus organized according to the following scheme: a execution of dipole electrical sounding pro-files, to depict a series of significant tomographic pseudosections, both across and along the new railway layout; b execution of self-potential measurements, to draw an anomaly map over the whole hydrogeological network system in the survey area. The research provided information which has helped to improve the geological-structural model of the area and disclosed the hydrogelogic network, conforming to the classified field surface manifestations. At present, further detailed field investigations are being carried out, which confirm all the results obtained by the geoelectrical survey.

  2. Energy storage on board of railway vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, M.; Scholten, J. [Bombardier Transportation, Mannheim (Germany)

    2004-07-01

    The proposed energy storage on board of a Railway vehicle leads to a big step in the reduction of consumed energy. Up to 30% energy saving are expected in a light rail vehicle, at the same time reducing the peak power demand drastically. In addition, with the energy storage an operation without catenary could become reality, which was successfully demonstrated with the prototype light rail vehicle driving with switched off pantograph. This prototype vehicle is in passenger operation since September 2003, the implemented software is optimised on energy savings and first experience is very promising. (authors)

  3. The importance of railway noise in France

    CERN Document Server

    Maurin, M

    1979-01-01

    A national survey on environmental nuisances due to all forms of transport was made in France during 1977. From among the data gathered, it is possible to extract results concerning the impact of nuisance due to railways, partly from results of questionnaires and partly from results of acoustical measurements. Interviews and measurements were made in several towns, at randomly selected dwellings. Rail and air transport noise nuisance impacts appeared to be of comparable importance, with that of road transport very much larger than either. (0 refs).

  4. Freight railway operator timetabling and engine scheduling

    DEFF Research Database (Denmark)

    Bach, Lukas; Gendreau, M.; Wøhlk, Sanne

    2015-01-01

    In this paper we consider timetable design at a European freight railway operator. The timetable is designed by choosing the time of service for customer unit train demands among a set of discrete points. These discrete points are all found within the a time-window. The objective of the model...... is to minimize cost while adhering to constraints regarding infrastructure usage, demand coverage, and engine availability. The model is solved by a column generation scheme where feasible engine schedules are designed in a label setting algorithm with time-dependent cost and service times....

  5. A mathematical model for optimum single-commodity distribution in the network of chain stores: a case study of food industry

    Directory of Open Access Journals (Sweden)

    Mohsen Cheshmberah

    2011-10-01

    Full Text Available Distribution refers to the steps taken to move and store a product from the suppliers to a customers in the supply chain and is a key driver of the overall profitability of a firm and overall supply chain. In this paper, a problem regarding managing of the move and store of goods are articulated and a mathematical model is presented to solve the model. The objective function is the total costs of distribution network, including transportation, storage rental, general warehousing, goods damages due to the transportation and storage, procurement, packing, and finally loading and unloading costs. The cost components described are defined based on the assumptions for a real distribution network of a chain stores firm. The aim of developing such a model is to find the optimum pattern to move and store goods based on the minimum cost of the distribution network.

  6. Application of artificial removal networks to estimation of the left-to-right cardiac or ductal shunts. Pt. 1. Studies on idealized mathematically created pulmonary radioangiograms

    International Nuclear Information System (INIS)

    Rudzki, K.; Rudzka, J.; Nowak, S.; Sadowski, T.; Czogala, E.

    1995-01-01

    The purpose of these studies was to examine usefulness of the artificial neural network for classification of the left-to-right cardiac or ductal shunt intensity. Our own program of stimulation of three-layer neural network was used. Studies were carried out on three series of mathematically created, idealized curves. Effect of changing the numbers of neural network processing elements on learning and recognition procedures was examined. There was a relation of the number of the rounds necessary to train up the net to the number of classes according to the shunt size (Qp/Qs) and to the number of curves in each class of training series. Using of learning series containing more curves in each class improves the ability to classification of curves by a trained-up neural network. Reducing the input data to 24 points of the down slope of the curve improves the learning ability of the network and classification of the radioangiograms. These studies suggest that the neural networks could be a useful tool of classification of pulmonary radioangiograms. (author). 2 figs, 4 tabs

  7. Assessment of railway wagon suspension characteristics

    Science.gov (United States)

    Soukup, Josef; Skočilas, Jan; Skočilasová, Blanka

    2017-05-01

    The article deals with assessment of railway wagon suspension characteristics. The essential characteristics of a suspension are represented by the stiffness constants of the equivalent springs and the eigen frequencies of the oscillating movements in reference to the main central inertia axes of a vehicle. The premise of the experimental determination of these characteristic is the knowledge of the gravity center position and the knowledge of the main central inertia moments of the vehicle frame. The vehicle frame performs the general spatial movement when the vehicle moves. An analysis of the frame movement generally arises from Euler's equations which are commonly used for the description of the spherical movement. This solution is difficult and it can be simplified by applying the specific assumptions. The eigen frequencies solutions and solutions of the suspension stiffness are presented in the article. The solutions are applied on the railway and road vehicles with the simplifying conditions. A new method which assessed the characteristics is described in the article.

  8. Monitoring of railway bridges in Japan

    Science.gov (United States)

    Abe, Makoto; Komon, Kazuki; Narumoto, Asao; Sugidate, Masao; Mori, Takeshi; Miki, Chitoshi

    2000-06-01

    In Japan, some monitoring systems have been introduced to evaluate conditions of the railway structures. In this work, we introduce the monitoring systems of railway bridges. Here, for example, we show the abstraction of fatigue damage monitoring system. The crack propagation properties of a side notched SUS304 thin sheet, which is affixed to a fatigue test specimen, is studied to develop a fatigue damage monitoring sensor. When cyclic loads are applied to the fatigue specimen, the side notched thin sheet behaves as a displacement controlled condition. The stress intensity factor (Delta) K is expressed by the following equation; (Delta) K equals (Delta) (sigma) (root)GL/2 where GL is the gauge length of the thin sheet. The thin sheet is fatigue pre-cracked, stress- relieved and affixed to a specimen. The results of fatigue crack propagation tests show that the crack propagation rate is dependent on stress range and gauge length, but not on crack length. Under sufficient mean stress conditions, the fatigue crack propagation rate is well expressed by a power low of (Delta) K even at such a low stress range as 20 MPa. Fatigue damage accumulated during a monitoring period can be estimated from crack propagation during the period. The sensitivity of the sensor is controlled through the gauge length of the sensor.

  9. Simplified Transit Procedure in Railway Transport

    Directory of Open Access Journals (Sweden)

    Željko Kokorović

    2008-11-01

    Full Text Available The current transit procedure in railway transport that iscarried out on the basis of the Customs Act [ 11 of the Republicof Croatia is applied only up to the border, i. e. the issued documentsand guarantees are valid only up to the border, and byjoining the Convention on Common transit procedure, i. e. integrationof the Republic of Croatia in the European Union, theRepublic of Croatia will also have to implement the regulationsand rules of Simplified transit procedure valid in each of thethirty member states. In international railway traffic, the transportof goods is regulated by the Convention concerning InternationalCarriage by Rail- COT IF [2 1 and usage of the CIMwaybill (Contract for International Carriage of Goods by Rail.If the goods are transported in Simplified transit procedure, theformalities regarding the transport of goods performed by railcarriers using the international waybill CIM will be significantlysimplified and accelerated. In principle there are no delays dueto customs on the borders when crossing the EU borders andborders of the Convention member states, contributing greatlyto the acceleration of the transport of goods, reduction of waitingcosts and paperwork, as well as influence on the schedulereliability.

  10. Electromagnetic Vibration Energy Harvesting for Railway Applications

    Directory of Open Access Journals (Sweden)

    Bradai S.

    2018-01-01

    Full Text Available Safe localization of trains via GPS and wireless sensors is essential for railway traffic supervision. Especially for freight trains and because normally no power source is available on the wagons, special solutions for energy supply have to be developed based on energy harvesting techniques. Since vibration is available in this case, it provides an interesting source of energy. Nevertheless, in order to have an efficient design of the harvesting system, the existing vibration needs to be investigated. In this paper, we focus on the characterization of vibration parameters in railway application. We propose an electromagnetic vibration converter especially developed to this application. Vibration profiles from a train traveling between two German cities were measured using a data acquisition system installed on the train’s wagon. Results show that the measured profiles present multiple frequency signals in the range of 10 to 50 Hz and an acceleration of up to 2 g. A prototype for a vibration converter is designed taking into account the real vibration parameters, robustness and integrability requirements. It is based on a moving coil attached to a mechanical spring. For the experimental emulation of the train vibrations, a shaker is used as an external artificial vibration source controlled by a laser sensor in feedback. A maximum voltage of 1.7 V peak to peak which corresponds to a maximum of 10 mW output power where the applied excitation frequency is close to the resonant frequency of the converter which corresponds to 27 Hz.

  11. Guideline for load and resistance assessment of existing european railway bridges

    OpenAIRE

    JENSEN, Jens S; CASAS, Joan R; KAROUMI, Raid; PLOS, Mario; CREMONA, Christian; MELBOURNE, Clive

    2008-01-01

    Many of the European railway bridges are getting close to the end of their service life. At the same time the railway operators demand higher axle loads for freight trains and higher speeds for passenger trains. This requires new and better approaches for assessing both the railway loads and the resistance of railway bridges. The main objective of the "Guideline for Load and Resistance Assessment of Existing European Railway Bridges", developed within EU founded project "Sustainable Bridge...

  12. Mathematics and Literature

    Institute of Scientific and Technical Information of China (English)

    田琳

    2016-01-01

    In both China and the West, mathematics is closely connected with literature. The maths thought implied in Chinese and western literature is worth our study, and the maths thought in the field of literature is also appear in aesthetics and philoso-phy, so literature, mathematics, aesthetics and philosophy become a network of interconnected.

  13. Features of formation of car-traffic in a regional transportation system in conditions the multi-agents organization of a railway transportation

    Directory of Open Access Journals (Sweden)

    Aleksandr Leonidovich Kazakov

    2011-09-01

    Full Text Available As a result of structural reform of Russian railways, a host of agents that provide customers with loading resources, especially wagons for transport by railway. These processes reduce in efficiency of the car fleet, increasing transportation costs, shortage of cars for many customers, an increase of empty runs and, as a result, a depletion of a number of sections of the network carrying capacity at a reduced total volume of rail traffic. The article describes the reasons for this situation due to the mismatch occurred heterogeneity of rolling stock to existing planning conditions and tariffs. It is also shown that the inefficiency of decentralized car fleet contributes to the predominance of tree-type network, and the importance of this factor in the new environment has increased substantially. To ensure the efficient operation of rail transport as a systemic industry, providing mass-haul transport, it is proposed for integration into a regional logistics. Freight terminals regional logistics transportation and distribution system (RLTRS is appropriate to create on the basis of major freight railway stations. Thus, the adaptation of planning car traffic volume and train formation to modern standards, the establishment of tariff incentives and long-term changes in network configuration are considered as a prerequisite for the transformation of local transport and technological systems on the network of Russian railways into the integrated transport and logistics systems.

  14. Management of low adhesion on railway tracks in European countries

    DEFF Research Database (Denmark)

    Thommesen, Jacob; Duijm, Nijs Jan; Andersen, Henning Boje

    with purely technical aspects of e.g. braking and WSP systems, but focus on the implied requirements for organisations and drivers. The report is largely based on literature describing measures taken by existing railway organisations, comprising, besides a few journal article, largely reports by railway...... incident in 2011 in Denmark and the braking ability of a specific type of train (Havarikommissionen 2012), but since expanded to encompass general problems with low adhesion (Nielsen et al. 2012). This report thus addresses problems that are already well‐known to Danish railway organisations...

  15. Dynamic Response of Railway Bridges Subjected to Passing Vehicles

    Directory of Open Access Journals (Sweden)

    Moravčík Milan

    2017-12-01

    Full Text Available This paper discusses some issues related to dynamic effects in railway bridges focussed on the dynamic behaviour of the small and medium span simply supported railway bridges subjected to a series of moving vehicle. Presented parametric study is focused on the dynamic deflection of the simply supported railway bridge of the span Lb = 38 m, due to the series moving loads representing a conventional train with the IC-coaches, with the impact to the speed up to 160 km/h applied in Slovakia.

  16. An economic evaluation of setting up physical barriers in railway stations for preventing railway injury: evidence from Hong Kong.

    Science.gov (United States)

    Law, C K; Yip, P S F

    2011-10-01

    Setting physical barriers, for example platform screen doors (PSDs), has been proven to be effective in preventing falls onto railway tracks, but its cost-effectiveness is not known. For economic evaluation of public health interventions, the importance of including non-health factors has been noted despite a lack of empirical studies. This study aimed to investigate the effectiveness and cost-effectiveness of PSDs, which are installed in part of the Hong Kong railway system, for preventing railway injuries. Data on railway injuries from 1997 to 2007 were obtained from the railway operators. Poisson regression was used to examine the risk reduction. Two incremental cost-effectiveness ratios (ICER) were calculated to assess the cost-effectiveness based on (1) disability-adjusted life years (DALYs) only and (2) DALYs with potential fare revenue and passengers' waiting time lost due to railway circulation collapse. The PSD installation has effectively reduced railway injuries (adjusted 5-year average percentage change: -68.8%, pfair and appropriate value of the intervention's cost-effectiveness is needed.

  17. OPERATIONAL DISTRIBUTION OF THE TRAIN TRAFFIC VOLUME ON THE SECTIONS OF RAILWAY OPERATING DOMAIN

    Directory of Open Access Journals (Sweden)

    G. Ya. Моzolevich

    2013-10-01

    Full Text Available Purpose. The task of the operational distribution of train traffic volume on the sections of operating domain is the optimization one. It is solved in the operational conditions by the dispatch station. The article sets the problem of formalizing and finding the new ways to solve this urgent problem. Methodology. A new approach to solving the problem of operational distribution of train traffic volume on the sections of the rail network with a choice of routes for all train traffics was proposed. Findings. A study of possible routes for the train traffic handle on the operating domain used for mass freight transportations between Krivyi Rih and Donbas was carried out. The use of the proposed method allowed us to obtain a rational distribution of trains on the rail network sections. Originality. The method of train traffic volume distribution in the network under operational conditions was improved. The method, as opposed to the current one allows one to select the route of separate units handle (according to the criteria of the weighted average cost for 1 ton of cargo. Practical value. The use of the proposed technology of the operational distribution of train traffic volume will increase the efficiency of the railways in general and ensure the competitiveness of rail transportations. The methodology implementation involves the use of railway dispatch station for the automated workplaces with appropriate informational support.

  18. Modelling of a Double-Track Railway Contact System Electric Field Intensity

    Science.gov (United States)

    Belinsky, Stanislav; Khanzhina, Olga; Sidorov, Alexander

    2017-12-01

    Working conditions of personnel that serves contact system (CS) are affected by factors including health and safety, security and working hours (danger of rolling stock accidents, danger of electric shock strokes, work at height, severity and tension of work, increased noise level, etc.) Low frequency electromagnetic fields as part of both electric and magnetic fields are among of the most dangerous and harmful factors. These factors can affect not only the working personnel, but also a lot of people, who do not work with the contact system itself, but could be influenced by electromagnetic field as the result of their professional activity. People, who use public transport or live not far from the electrified lines, are endangered by these factors as well. There are results of the theoretical researches in which low frequency electric fields of railway contact system were designed with the use of mathematical and computer modelling. Significant features of electric field distribution near double-track railway in presence or absence of human body were established. The studies showed the dependence of low frequency electric field parameters on the distance to the track axis, height, and presence or absence of human body. The obtained data were compared with permissible standards established in the Russian Federation and other countries with advanced electrified railway system. Evaluation of low frequency electric fields harmful effect on personnel is the main result of this work. It is also established, that location of personnel, voltage and current level, amount of tracks and other factors influence electric fields of contact systems.

  19. Mathematical Modelling and Optimization of Cutting Force, Tool Wear and Surface Roughness by Using Artificial Neural Network and Response Surface Methodology in Milling of Ti-6242S

    Directory of Open Access Journals (Sweden)

    Erol Kilickap

    2017-10-01

    Full Text Available In this paper, an experimental study was conducted to determine the effect of different cutting parameters such as cutting speed, feed rate, and depth of cut on cutting force, surface roughness, and tool wear in the milling of Ti-6242S alloy using the cemented carbide (WC end mills with a 10 mm diameter. Data obtained from experiments were defined both Artificial Neural Network (ANN and Response Surface Methodology (RSM. ANN trained network using Levenberg-Marquardt (LM and weights were trained. On the other hand, the mathematical models in RSM were created applying Box Behnken design. Values obtained from the ANN and the RSM was found to be very close to the data obtained from experimental studies. The lowest cutting force and surface roughness were obtained at high cutting speeds and low feed rate and depth of cut. The minimum tool wear was obtained at low cutting speed, feed rate, and depth of cut.

  20. Mathematical Cultures : the London Meetings 2012-2014

    CERN Document Server

    2016-01-01

    This collection presents significant contributions from an international network project on mathematical cultures, including essays from leading scholars in the history and philosophy of mathematics and mathematics education. Mathematics has universal standards of validity. Nevertheless, there are local styles in mathematical research and teaching, and great variation in the place of mathematics in the larger cultures that mathematical practitioners belong to. The reflections on mathematical cultures collected in this book are of interest to mathematicians, philosophers, historians, sociologists, cognitive scientists and mathematics educators.

  1. Automated vehicle for railway track fault detection

    Science.gov (United States)

    Bhushan, M.; Sujay, S.; Tushar, B.; Chitra, P.

    2017-11-01

    For the safety reasons, railroad tracks need to be inspected on a regular basis for detecting physical defects or design non compliances. Such track defects and non compliances, if not detected in a certain interval of time, may eventually lead to severe consequences such as train derailments. Inspection must happen twice weekly by a human inspector to maintain safety standards as there are hundreds and thousands of miles of railroad track. But in such type of manual inspection, there are many drawbacks that may result in the poor inspection of the track, due to which accidents may cause in future. So to avoid such errors and severe accidents, this automated system is designed.Such a concept would surely introduce automation in the field of inspection process of railway track and can help to avoid mishaps and severe accidents due to faults in the track.

  2. Framework for Railway Phase-based Planning

    DEFF Research Database (Denmark)

    Li, Rui; Landex, Alex; Nielsen, Otto Anker

    spending) to evaluate the project alternatives. The comparison result can identify the most cost-efficient solution in a long run and therefore reduce the overall costs. This article defines a phase-based framework to guide the railway maintenance and renewal project planning at strategic level....... The framework evaluates the project options from a larger LCC scope: The costs from train operation companies and passengers, together with the maintenance and renewal costs from Infrastructure Managers are included in the calculation. The framework simplifies the planning processes and the LCC calculation...... and compared. A case study is introduced in the article to demonstrate how the framework works to compare timber sleepers and concrete sleepers from strategic planning level. Two Life Cycle Cost oriented policies are discussed to illustrate: high quality track is necessity to improve the cost efficiency...

  3. Overhead mining railway, particularly for underground use

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, L

    1976-05-20

    Overhead mining railways are usually equipped with a friction wheel drive in underground use. This drive has the advantage over a gear drive that it is more robust and therefore more economic. However, it produces unsatisfactory running for difficult sections with steep gradients up or down or places where deposits of grease and dirt are inevitable. It is proposed to change over to a gear drive at such sections. The high degree of wear, which is characteristic of this type of drive, can be reduced if the drive is only used in difficult sections. It is proposed that the gear drive should be automatically switched on and off by means of stops or contacts on the rails.

  4. Basic stages of introduction of kontrolingu in management railway enterprises

    OpenAIRE

    Kokovikhina, O.

    2011-01-01

    In the article research existent approaches in relation to introduction of financial kontrolingu in activity of subjects of menage and ten stages of introduction of kontrolingu are offered in the management of railway transport enterprises.

  5. Complex eigenvalue analysis of railway wheel/rail squeal

    African Journals Online (AJOL)

    DR OKE

    Squeal noise from wheel/rail and brake disc/pad frictional contact is typical in railways. ... squeal noise by multibody simulation of a rail car running on rigid rails. ... system, traditional complex eigenvalue analysis by finite element was used.

  6. Storage Space Allocation of Inbound Container in Railway Container Terminal

    Directory of Open Access Journals (Sweden)

    Li Wang

    2014-01-01

    Full Text Available Efficient storage strategy of railway container terminals is important in balancing resource utilization, reducing waiting time, and improving handling efficiency. In this paper, we consider the formulation and solution algorithm for storage space allocation problem of inbound containers in railway container terminal. The problem is formulated as two-stage optimization models, whose objectives are balancing the workload of inbound containers and reducing the overlapping amounts. An algorithm implement process based on rolling horizon approach is designed to solve the proposed models. Computational experiments on an actual railway container terminal show that the proposed approach is effective to solve space allocation problem of inbound container and is significant for the operation and organization of railway container terminals.

  7. An integrated micro-macro approach to robust railway timetabling

    DEFF Research Database (Denmark)

    Bešinović, Nikola; Goverde, Rob M P; Quaglietta, Egidio

    2016-01-01

    With the increasing demand for railway transportation infrastructure managers need improved automatic timetabling tools that provide feasible timetables with enhanced performance in short computation times. This paper proposes a hierarchical framework for timetable design which combines a microsc...

  8. Railway Transportation Engineering (CEE 408) Course updates and online conversion.

    Science.gov (United States)

    2017-01-20

    The new order of lectures provides students with a sound introduction to the main concepts behind efficiency and economic railway operations. This naturally follows into the design of railcars for safe, efficient and economical operations. With railc...

  9. Synergies of the Liberalization of the Railway Transport Market

    Directory of Open Access Journals (Sweden)

    Panák Michal

    2017-01-01

    Full Text Available The liberalization of transport market brings various effects, which in the context of the assessment of synergies can affect in different ways the company, a customer as such, and transport undertakings operating on the railway transport market as well. This paper provides an innovative perspective on the relationship between liberalization and synergy, defining new types of synergies that have not yet been monitored in the conditions of railway transport. This approach is interesting because of the possibility of assessing the operation of railway undertakings in the open transport market. The eminent is characteristic of integration type synergies and emergence type synergies in relation to railway transport, as well as the breakdown of synergies in relation to the customer and carrier.

  10. High speed railway track dynamics models, algorithms and applications

    CERN Document Server

    Lei, Xiaoyan

    2017-01-01

    This book systematically summarizes the latest research findings on high-speed railway track dynamics, made by the author and his research team over the past decade. It explores cutting-edge issues concerning the basic theory of high-speed railways, covering the dynamic theories, models, algorithms and engineering applications of the high-speed train and track coupling system. Presenting original concepts, systematic theories and advanced algorithms, the book places great emphasis on the precision and completeness of its content. The chapters are interrelated yet largely self-contained, allowing readers to either read through the book as a whole or focus on specific topics. It also combines theories with practice to effectively introduce readers to the latest research findings and developments in high-speed railway track dynamics. It offers a valuable resource for researchers, postgraduates and engineers in the fields of civil engineering, transportation, highway & railway engineering.

  11. THE EVALUATION OF OUTSOURCING USE ON UKRAINIAN RAILWAY TRANSPORT

    Directory of Open Access Journals (Sweden)

    O. M. Stasiuk

    2009-04-01

    Full Text Available The estimate of outsourcing possibilities on the railway transport of Ukraine is realized. The kinds of activities, which are promising for transfer through outsourcing to small enterprises, are proposed.

  12. IMPROVING THE POSITIONING ACCURACY OF TRAIN ON THE APPROACH SECTION TO THE RAILWAY CROSSING

    Directory of Open Access Journals (Sweden)

    V. I. Havryliuk

    2016-02-01

    Full Text Available Purpose. In the paper it is necessary to analyze possibility of improving the positioning accuracy of train on the approach section to crossing for traffic safety control at railway crossings. Methodology. Researches were performed using developed mathematical model, describing dependence of the input impedance of the coded and audio frequency track circuits on a train coordinate at various values of ballast isolation resistances and for all usable frequencies. Findings. The paper presents the developed mathematical model, describing dependence of the input impedance of the coded and audio-frequency track circuits on the train coordinate at various values of ballast isolation resistances and for all frequencies used in track circuits. The relative error determination of train coordinate by input impedance caused by variation of the ballast isolation resistance for the coded track circuits was investigated. The values of relative error determination of train coordinate can achieve up to 40-50 % and these facts do not allow using this method directly for coded track circuits. For short audio frequency track circuits on frequencies of continuous cab signaling (25, 50 Hz the relative error does not exceed acceptable values, this allow using the examined method for determination of train location on the approach section to railway crossing. Originality. The developed mathematical model allowed determination of the error dependence of train coordinate by using input impedance of the track circuit for coded and audio-frequency track circuits at various frequencies of the signal current and at different ballast isolation resistances. Practical value. The authors proposethe method for train location determination on approach section to the crossing, equipped with audio-frequency track circuits, which is a combination of discrete and continuous monitoring of the train location.

  13. ECONOMIC EFFECT OF INTRODUCTION OF MODULAR TECHNOLOGY IN RAILWAY INDUSTRY

    Directory of Open Access Journals (Sweden)

    Artem Bilous

    2015-11-01

    Full Text Available The purpose of the paper is to explore the current state of the railway engineering industry in the world, the problems of its development prospects, especially the introduction of the modular process technology and economic impact of its introduction. Methodology. The research is based on statistical information from public sources, which is used to confirm the veracity of the thesis put forward about the feasibility of further implementation of the principle of modularity in the railway engineering sector. Data was also obtained from the websites of manufacturers of railway equipment. Also, in the study of the issue, analytical articles on the economic development of the sector of railway engineering in the world were used. Results of the research showed that today, in transport engineering industry, in particular – in the railway engineering, there is a problem of inefficient implementation and use of technological developments, which are used in the manufacture of railway rolling stock. Many technical solutions are duplicated, leading to more time and financial costs. At the same time, there is no free access to information about existing technical solutions, which significantly slows down the development of rail transport. One of the main solutions to the problem is the use of modular technology in the design and manufacture of rolling stock. Leading global manufacturers have already begun to use the modules in the production of their rolling stock, but the technology is not yet sufficiently developed and finds its realization only in reducing the costs of production of rolling stock by specific manufacturers. The full benefits of the new technology have not yet been obtained by producers and operators. Thus, there is a considerable margin for the implementation of modular technology in the production of railway vehicles, which will result in further reducing both production costs and the costs of maintenance, operation and repair of

  14. An investigation of employee motivation at Botswana railways / John Latolang

    OpenAIRE

    Latolang, John

    2011-01-01

    Botswana Railways has been facing low employee motivation and productivity for some time. Companies such as Air Botswana which had been experiencing similar issues decided to privatise to increase its efficiency and, as a result, turned things around. Hence, using both quantitative and qualitative investigation at the Headquarters of the Botswana Railways, this study sought to determine the extent of employee motivation and how to enhance it in order to increase employee produc...

  15. Railway projects prioritisation for investment : application of goal programming

    OpenAIRE

    Ahern, Aoife; Anandarajah, Gabrial

    2007-01-01

    This research develops a weighted integer goal-programming model for prioritising railway projects for investment. The goal of the model is to prioritise the identified projects for investment while maximising the objectives and meeting the budget limit for capital investment. The model minimises the goal deviations of the objectives. The objectives of the model include quantitative and qualitative attributes. The model is applied to prioritise the new railway projects, which have a total cos...

  16. Study on high reliability safety valve for railway vehicle

    Science.gov (United States)

    Zhang, Xuan; Chen, Ruikun; Zhang, Shixi; Xu, BuDu

    2017-09-01

    Now, the realization of most of the functions of the railway vehicles rely on compressed air, so the demand for compressed air is growing higher and higher. This safety valve is a protection device for pressure limitation and pressure relief in an air supply system of railway vehicles. I am going to introduce the structure, operating principle, research and development process of the safety valve designed by our company in this document.

  17. Distributed optical fiber sensors for integrated monitoring of railway infrastructures

    Science.gov (United States)

    Minardo, Aldo; Coscetta, Agnese; Porcaro, Giuseppe; Giannetta, Daniele; Bernini, Romeo; Zeni, Luigi

    2014-05-01

    We propose the application of a distributed optical fiber sensor based on stimulated Brillouin scattering, as an integrated system for safety monitoring of railway infrastructures. The strain distribution was measured dynamically along a 60 meters length of rail track, as well as along a 3-m stone arch bridge. The results indicate that distributed sensing technology is able to provide useful information in railway traffic and safety monitoring.

  18. SOLUTION FOR AN EQUIPMENT OF RAILWAY BRIDGE MONITORING

    Directory of Open Access Journals (Sweden)

    Liviu Mihai SIMA

    2009-11-01

    Full Text Available This paper presents a solution for the railway bridges monitoring based on the use of already existing equipments in the railway installations and some new equipments based on photo-elements, as well. This kind of equipments can function in continue and discontinuous regime, means of them tracking down if the bridge piles suffered movements by different reasons. This aspect can put in danger the safety of the circulation on that bridge.

  19. A modelling approach for railway overhead line equipment asset management

    OpenAIRE

    Kilsby, Paul; Remenyte-Prescott, Rasa; Andrews, John

    2017-01-01

    The Overhead Line Equipment (OLE) is a critical sub-system of the 25kV AC overhead railway electrification system. If OLE asset management strategies can be evaluated using a whole lifecycle cost analysis that considers degradation processes and maintenance activities of the OLE components, the investment required to deliver the level of performance desired by railway customers and regulators can be based on evidence from the analysis results. A High Level Petri Net (HLPN) model, proposed in ...

  20. Development of a super high speed railway and ML 100

    Energy Technology Data Exchange (ETDEWEB)

    Usami, Y

    1973-07-01

    A history of the development progress is given, followed by a discussion of the propulsion system for a super high speed railway-structure. Induction linear motors and synchronous linear motors are discussed in some detail. The maintenance system is then described (basic test apparatus-rotary type superconductive magnetic force maintenance system, etc.). Experiments using a linear running superconductive magnetic test car are discussed. Developments of super high speed railways in America, France, England, West Germany, etc. are described.

  1. Reconstruction of railway energy lines; Rekonstruktion von Bahnenergieleitungen

    Energy Technology Data Exchange (ETDEWEB)

    Rothe, Matthias [DB Energie Gmbh, Berlin (Germany); Wahlen, Manfred [DB Energie Gmbh, Koeln (Germany)

    2013-06-15

    As is the case for other overhead lines, 110 kV railway energy lines are assumed to have a service life of 80 years. When this service life ends or the lines are adapted to the state of the art as necessary, all components of the overhead line are renewed. For the reconstruction of railway energy lines, the specifications laid down in planning and environmental laws, operational management aspects and the local ambient and development situation are decisive project planning parameters. (orig.)

  2. Automatic Verification of Railway Interlocking Systems: A Case Study

    DEFF Research Database (Denmark)

    Petersen, Jakob Lyng

    1998-01-01

    This paper presents experiences in applying formal verification to a large industrial piece of software. The are of application is railway interlocking systems. We try to prove requirements of the program controlling the Swedish railway Station Alingsås by using the decision procedure which...... express thoughts on what is needed in order to be able to successfully verify large real-life systems....

  3. Perspectives of transport logistics in the railway transport enterprises

    OpenAIRE

    Elagin, Yu; Obruch, A.

    2014-01-01

    In this paper, the authors study the main directions of development of transport logistics. Identified as the main types of general transport logistics, as well as the rail sector, in which logistics acquires a dominant role in terms of reform. Also highlights the main features of transport logistics for railway transport enterprises and proved the importance of integrating function in modern conditions of development. The authors noted that to ensure the effective development of railway tran...

  4. CREATION OF EXPORT-ORIENTED NETWORK OF GRAIN ELEVATORS IN UKRAINE

    Directory of Open Access Journals (Sweden)

    D. M. Kozachenko

    2017-04-01

    Full Text Available Purpose. The scientific paper highlights improving the efficiency of export rail transportation of grain cargoes in Ukraine by introducing shipper routing and concentration of loading at the terminal grain elevators. Methodology. According to the experience of the USA and Canada, one of the most effective ways to reduce costs in the grain to-port supply chain is a shipper routing of the rail traffic. Shipper routing for transportation of grain cargoes involves the concentration of their loading on the multiple junctions. The junctions are proposed to be selected with the use of cluster analysis methods. For the formation of the grain loading concentration areas the authors used methods of set theory and multi-criteria optimization. Findings. Based on agglomerative cluster analysis algorithm, the junctions on a network of Ukrainian railways are selected and the areas of possible concentration of grain loading are formed. DSU-algorithm allowed distinguishing the overlapping and non-overlapping areas of concentration. The problem of selecting non-overlapping areas of the grain loading concentration is formalized as the problem of multiobjective integer programming with boolean variables. The solution of this problem by a modified simplex algorithm allows selecting on the railway network of Ukraine 24 districts of possible grain loading concentration, which cover 70 stations and at minimal additional cost provide routing of about 7.5 million tons of grain per year. Originality. The originality of the work lies in the fact that the authors developed the mathematical procedure for selection of junctions and concentration areas of grain loading at the Ukrainian railway network, taking into account the economic efficiency of the process. Practicalvalue. Application of the developed method of grain loading concentration for the formation of unit trains will significantly reduce the logistics costs in the supply chain of grain to Ukrainian ports for

  5. Operating a railway system within a challenging environment: Economic history and experiences of Zimbabwe’s national railways

    Directory of Open Access Journals (Sweden)

    Charles Mbohwa

    2008-11-01

    Full Text Available This paper presents a historical background to the development of the railways in Zimbabwe and then discusses their current state. Besides being a landlocked country in Southern Africa, Zimbabwe has since 2000 been saddled with socio-economic and political challenges which have seen a decline in all economic indices, hence posing some challenges to its railways. This article discusses the challenges faced by the railways as a result of high inflation, unstable currency exchange rate, brain drain, poor management, government interference in management, customs border delays, and energy shortage. The problems have been addressed in unique ways and unusual solutions are proposed. These include customer financing for maintenance and spares and the resuscitation of steam locomotives. The presented solutions, lessons and issues from this experience contribute to discussions and study of railway logistics in challenging environments. Finally, current and future research issues, which have a global appeal, are presented.

  6. Investigating High-Speed Railways In Terms Of The Economy For Our Country and The Region

    OpenAIRE

    Şahin, Onur; Altan, Mehmet Fatih

    2018-01-01

    High-speed railways have a history of more than 40 years. Railways continued to be popular especially in variousparts of Eastern Europe and Asia until the end of the 1980s. As of today, we can talk about a high-speed railway thatcontinues to develop in the continents of Africa, Asia and the Americas around the world. At this point, one of themost significant factors in railways, in particular high-speed railways, is planning. Planning determines the effect ofthe railway on the economy, as wel...

  7. Mathematics Underground

    Science.gov (United States)

    Luther, Kenneth H.

    2012-01-01

    Mathematical modeling of groundwater flow is a topic at the intersection of mathematics and geohydrology and is rarely encountered in undergraduate mathematics. However, this subject is full of interesting and meaningful examples of truly "applied" mathematics accessible to undergraduates, from the pre-calculus to advanced mathematics levels. This…

  8. Biological mechanisms beyond network analysis via mathematical modeling. Comment on "Network science of biological systems at different scales: A review" by Marko Gosak et al.

    Science.gov (United States)

    Pedersen, Morten Gram

    2018-03-01

    Methods from network theory are increasingly used in research spanning from engineering and computer science to psychology and the social sciences. In this issue, Gosak et al. [1] provide a thorough review of network science applications to biological systems ranging from the subcellular world via neuroscience to ecosystems, with special attention to the insulin-secreting beta-cells in pancreatic islets.

  9. Inspection and Numerical Analysis of an Ottoman Railway Bridge in Jordan

    Directory of Open Access Journals (Sweden)

    Amin H. Almasri

    2016-01-01

    Full Text Available The construction of bridges represents a big challenge, since they require enormous economic effort and specialized technical skills. Bridges were historically important as they help connecting people and thus diffusing cultures, sharing ideas, and providing the backbone of transportation networks. This study focuses on the inspection and structural analysis of a 20th-century Ottoman railway stone arched bridge located on the Hejaz railway network in Jordan. The bridge has a very important cultural heritage value which stems from its history. The bridge stone material was cut and tested to determine its strength, in order to be used in the analysis. The structural analysis was carried out to assess the structural condition of the bridge and its suitability for reuse. The study includes static analysis under gravity loads and seismic analysis under earthquake loads. Despite the existence of deterioration in the bridge body construction materials due to a combination of human and natural factors, the analysis results proved enough structural capability to sustain the imposed gravity loads, but not a strong earthquake.

  10. Soil erosion on road and railways embankments in the Canyoles river Basin. Eastern Spain.

    Science.gov (United States)

    Cerdà, Artemi; Antonio, Giménez-Morera; Félix Ángel, González-Peñaloza; María, Burguet; Paulo, Pereira; José Reyes, Ruiz

    2013-04-01

    Mediterranean landscapes are man-made. Its human ecosystems are characterized by a high population density, a long history of human settlement and an intense exchange of goods and people (Cerdà et al., 2010). This was possible due to a dense road network, most of it created during the Roman Empire. Modern roads and railways increased drastically during the last 30 years in the Mediterranean. Spain is a clear example of the acceleration of the road and railway infrastructures (Bel, 2005), especially during the 1960s as the tourism started to become a big issue in this part of the World. The increase in road and railways during the last 30 years resulted in a new transport system in Spain, which is based on high-speed railways and motorways. The characteristic of these infrastructures is that they were built by means of embankments, and little is now about the erosional response of those embankments to rainfall. The objective of this research is to assess the soil losses measured in road and railway embankments. The Canyoles River watershed was selected as an example of a region with a dense and recently developed modern network of roads, motorways and railway. The Canyoles river watershed is the natural path between the Mediterranean coast and Central Spain, the capital of the country and the touristic regions. Two motorways and two railways were built or re-built during the last two years and this paper assesses their impact on soil and water losses. As soil erosion rates are dependent on the high intensity - low frequency rainfall events, rainfall simulation experiments (40 experiments) were conducted (1 m2 plots; 60 minutes duration; 78 mm h-1 intensity) were carried out over plots on 2 railway (n=10 + 10) and motorway (n=10 + 10) research sites in August 2011, under very dry conditions. Soil moisture was below 5 % in the top 2 cm soil layer. The vegetation cover was very low in the two road and two railway embankments as the average cover was 4.2 % ranging from

  11. Mathematics Connection

    African Journals Online (AJOL)

    MATHEMATICS CONNECTION aims at providing a forum topromote the development of Mathematics Education in Ghana. Articles that seekto enhance the teaching and/or learning of mathematics at all levels of theeducational system are welcome.

  12. Applied Railway Optimization in Production Planning at DSB-S-tog - Tasks, Tools and Challenges

    DEFF Research Database (Denmark)

    Clausen, Jens

    2007-01-01

    these conflicting goals. S-tog has therefore on the strategic level decided to use software with optimization capabilities in the planning processes. We describe the current status for each activity using optimization or simulation as a tool: Timetable evaluation, rolling stock planning, and crew scheduling...... to the customers, and has concurrently been met with demands for higher efficiency in the daily operation. The plans of timetable, rolling stock and crew must hence allow for a high level of customer service, be efficient, and be robust against disturbances of operations. It is a highly non-trivial task to meet....... In addition we describe on-going efforts in using mathematical models in activities such as timetable design and work-force planning. We also identify some organizatorial key factors, which have paved the way for extended use of optimization methods in railway production planning....

  13. Dynamic Forces between the Rails and the Wheels of Railway Vehicle

    Directory of Open Access Journals (Sweden)

    Zdravko Peran

    2016-02-01

    Full Text Available The process of acquisition of the measured dynamic values of forces between the rails and the wheels on the real measurement train and the train tracks. The conversion of the measured values into the matrices and vectors enables numerous exact qualitative and quantitative studies of the dynamic phenomena behaviour. The paper shows the possibilities of using MATLAB computer tool. All the commands in the software are given and explained. Calculating of the empirical, normal and cumulative distribution on an example of the lateral force is given in detail. The new software is exactly verified mathematically and qualified for any further use. The developed software is the tool for the development of other two phases: software for the exact automatic evaluation of the maximum values of the dynamic values and software for the automatic approval of vehicles and railway due to the driving safety, loading tracks and driving comfort compared to the limited values regarding UI C CODE 518.

  14. Low-complexity Behavioral Model for Predictive Maintenance of Railway Turnouts

    DEFF Research Database (Denmark)

    Barkhordari, Pegah; Galeazzi, Roberto; Tejada, Alejandro de Miguel

    2017-01-01

    together with the Eigensystem Realization Algorithm – a type of subspace identification – to identify a fourth order model of the infrastructure. The robustness and predictive capability of the low-complexity behavioral model to reproduce track responses under different types of train excitations have been......Maintenance of railway infrastructures represents a major cost driver for any infrastructure manager since reliability and dependability must be guaranteed at all times. Implementation of predictive maintenance policies relies on the availability of condition monitoring systems able to assess...... the infrastructure health state. The core of any condition monitoring system is the a-priori knowledge about the process to be monitored, in the form of either mathematical models of different complexity or signal features characterizing the healthy/faulty behavior. This study investigates the identification...

  15. A Mathematical Study of Accessibility and Cohesion Degree in a High-Speed Rail Station Connected to an Urban Bus Transport Network

    Directory of Open Access Journals (Sweden)

    Mota Carmen

    2017-04-01

    Full Text Available In the last twenty years, the implementation of High-Speed Rail (HSR has been one of the major strategies for territorial structuring used by various countries. This model has enhanced the development of countries such as France, Spain, Germany and Japan. At present, the United States and China are also starting to implement this model. Nevertheless, the lack of social and economic profitability of several networks is being increasingly analysed. Many networks located in particular regions serve populations that are not large enough to recover the initial investment. For this reason, it is necessary to evaluate the population served by this transport mode, beyond the number of users. In this sense, it is essential to identify the deficiencies and potentials of implementing a network linked to other secondary networks in a specific territory which can compensate for the so-called tunnel effect. This article proposes to apply a mathematical approach based on graph theory to measure the Degree Accessibility Node (DAN in a constrained Geographic Information System (GIS model. Hence, it would be possible to compare regions, especially medium-sized cities, where the implementation of HSR could represent a qualitative leap due to incorporation into large transport networks. The DAN function uses static and dynamic studies to evaluate the level of connection of stations to secondary transport networks—local public transport in this case. Thus, the impact of high-speed trains could be spread to greater territorial and population ranges. Four cases have been studied, two in Germany (one of them, Fulda, is analysed in depth throughout this article and two in Spain. These two countries were selected since HSR was implemented in the same relative period of time, in comparison with other European countries. Results show relevant differences, suggesting a review of inappropriate policies of transport integration in a city that could weaken the expansion of

  16. A Mathematical Study of Accessibility and Cohesion Degree in a High-Speed Rail Station Connected to an Urban Bus Transport Network

    Science.gov (United States)

    Mota, Carmen; López, Miguel A.; Martínez-Rodrigo, Arturo

    2017-04-01

    In the last twenty years, the implementation of High-Speed Rail (HSR) has been one of the major strategies for territorial structuring used by various countries. This model has enhanced the development of countries such as France, Spain, Germany and Japan. At present, the United States and China are also starting to implement this model. Nevertheless, the lack of social and economic profitability of several networks is being increasingly analysed. Many networks located in particular regions serve populations that are not large enough to recover the initial investment. For this reason, it is necessary to evaluate the population served by this transport mode, beyond the number of users. In this sense, it is essential to identify the deficiencies and potentials of implementing a network linked to other secondary networks in a specific territory which can compensate for the so-called tunnel effect. This article proposes to apply a mathematical approach based on graph theory to measure the Degree Accessibility Node (DAN) in a constrained Geographic Information System (GIS) model. Hence, it would be possible to compare regions, especially medium-sized cities, where the implementation of HSR could represent a qualitative leap due to incorporation into large transport networks. The DAN function uses static and dynamic studies to evaluate the level of connection of stations to secondary transport networks—local public transport in this case. Thus, the impact of high-speed trains could be spread to greater territorial and population ranges. Four cases have been studied, two in Germany (one of them, Fulda, is analysed in depth throughout this article) and two in Spain. These two countries were selected since HSR was implemented in the same relative period of time, in comparison with other European countries. Results show relevant differences, suggesting a review of inappropriate policies of transport integration in a city that could weaken the expansion of the positive

  17. Epidemiology & preventive aspects of railway suicides and fatalities related to trespassing accidents.

    Science.gov (United States)

    Kumar, Sachil; Verma, Anoop K; Bhattacharya, Sandeep; Singh, Uma Shankar

    2013-11-01

    Suicide and trespass are major contributors to risk on the railway, resulting in around 170-180 fatalities per year in Lucknow region, as well as associated major disruption to the rail network. Lucknow is the capital city of the state of Uttar Pradesh in India. The analysis included train-pedestrian fatalities during 2007-2012. The data for 2007-2012 were collected from the autopsy reports of the university, case sheets from the hospital, the general prosecutor's investigations report and the inquest reports from police. The results show that the majority of victims were males. Half of the suicide victims were 20-39 years old. Accidents happened most frequently in situations when a person was walking on the tracks/in front of train (22.7%) or were crossing the tracks illegally (20.9%). Among all train-pedestrian fatalities, about half of the victims (42.8%) were intoxicated by alcohol. Female suicide victims suffered from mental health problems more frequently (55.8%) than male suicide victims. Overall, there is no reason to believe that train-pedestrian fatalities are unavoidable. By contrast, the effective prevention of railway suicides and accidents should be based on a systems approach involving effective measures introduces by several organisations such as government, railway organisations, various authorities (such as public health, education, enforcement, urban planning) and communities. Same measures can often be used to prevent both trespassing and suicides, even though their effectiveness may depend on the target group. In addition, there are measures specifically targeted to prevent either trespassing or suicides. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  18. RAMSES: a nowcasting system for mitigating geo-hydrological risk along the railway

    Science.gov (United States)

    Gabriele, Salvatore; Terranova, Oreste G.; Pascale, Stefania; Rago, Valeria; Chiaravalloti, Francesco; Sabatino, Pietro; Brocca, Luca; Laviola, Sante; Baldini, Luca; Federico, Stefano; Miglietta, Mario M.; Marra, Gian Paolo; Niccoli, Raffaele; Arcuri, Salvatore; Catalano, Filippo; Stassi, Sergio; Baccillieri, Maurizio; Agostino, Mario; Iovine, Giulio G. R.

    2016-04-01

    In recent years, a number of exceptional rainfall events of short / very short duration (from 15 minutes to about 2 hours) caused incidents and service interruptions due to landslides, collapses of bridges, and erosion of the ballast, along the Calabrian railway. RAMSES (RAilway Meteorological SEcurity System) is a pilot CNR project, recently co-funded by RFI S.p.A. and aimed at mitigating the risk along the railway. Forecasting of weather events responsible of heavy convective rainfall, even when provided with some advance, is not generally performed with reliable localization. In fact, objective limits of the numerical weather prediction derive from grid resolution, often exceeding the size of convective cells. These phenomena, whose recurrence periods seem to show a reduction due to climate changes, affect limited areas and are characterized by a very short life cycle. As a consequence, failures of hydraulic crossings are increasingly being recorded together with landslide-related debris invasion along the drainage network and slopes. RAMSES aims at improving short term (3-6 hours) weather forecasts and ground effects at local scale. The employed approach is base on synergistic and integrated operational tools to provide weather information on small-size basins. The system will also allow to promptly identify and track the short-term evolution (15-60 min) of convective cells, by means of imaging techniques based on quasi-real time radar and Meteosat data. The extension of the temporal horizon of the forecast up to three hours will be performed by using the Local Analysis and Prediction System (LAPS) model. This latter employs, as a "first guess", the output of the WRF numerical model: such analyses are updated and improved by means of observational data from different instruments (e.g. on land weather stations, radar, satellites, etc.). Finally, the assessment of ground effects will be accomplished for selected study areas, by means of landslide susceptibility

  19. Stiffness of Railway Soil-Steel Structures

    Directory of Open Access Journals (Sweden)

    Machelski Czesław

    2015-12-01

    Full Text Available The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces, as in bridges. The analyzed cases show that the shell’s span, geometry (static scheme and the height of earth fill influence the stiffness of the structure. The soil-steel structure’s characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  20. OOA composite structures applicable in railway industry

    Directory of Open Access Journals (Sweden)

    Rusnáková Soňa

    2017-01-01

    Full Text Available Composite sandwich structures offers several advantages over conventional structural materials such as lightweight, high bending and torsional stiffness, superior thermal insulation and excellent acoustic damping. In the aerospace industry, sandwich composites are commonly manufactured using the autoclave process which is associated with high operating cost. Out-of-autoclave (OOA manufacturing has been shown to be capable of producing low cost and high performance composites. In this paper we present results of experimental testing of various sandwich materials according various standards and actual requirements in transport industry. We compared the different types of surface and paint systems, because these layers are the most important in contact with the surrounding environment and load conditions. In the experimental measurements were used various materials. For the core of the sandwich structure were selected aluminium honeycomb, aramid honeycomb and PET (Polyethylene terephthalate foam core. Support layers were chosen two kinds of predimpregnated materials. The conditions of measurements were requirements for strength and rigidity, safety - flame resistance and reflectivity resistance. The samples were tested at the 3 - point bending test according to standard EN ISO 178, by modified test to determine the force required to rapture threaded insert, by test of reflectivity according to UIC CODE 844-4 R and according to standard EN 45545-2 fire protection of railway vehicles.

  1. Railway bridge monitoring during construction and sliding

    Science.gov (United States)

    Inaudi, Daniele; Casanova, Nicoletta; Kronenberg, Pascal; Vurpillot, Samuel

    1997-05-01

    The Moesa railway bridge is a composite steel concrete bridge on three spans of 30 m each. The 50 cm thick concrete deck is supported on the lower flanges of two continuous, 2.7 m high I-beams. The bridge has been constructed alongside an old metallic bridge. After demolishing this one, the new bridge has been slid for 5 m by 4 hydraulic jacks and positioned on the refurbished piles of the old bridge. About 30 fiber optic, low-coherence sensors were imbedded in the concrete deck to monitor its deformations during concrete setting and shrinkage, as well as during the bridge sliding phase. In the days following concrete pour it was possible to follow its thermal expansion due to the exothermic setting reaction and the following thermal and during shrinkage. The deformations induced by the additional load produced by the successive concreting phases were also observed. During the bridge push, which extended over six hours, the embedded and surface mounted sensors allowed the monitoring of the curvature variations in the horizontal plane due to the slightly uneven progression of the jacks. Excessive curvature and the resulting cracking of concrete could be ruled out by these measurements. It was also possible to observe the bridge elongation under the heating action of the sun.

  2. Stiffness of Railway Soil-Steel Structures

    Science.gov (United States)

    Machelski, Czesław

    2015-12-01

    The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness) become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces), as in bridges. The analyzed cases show that the shell's span, geometry (static scheme) and the height of earth fill influence the stiffness of the structure. The soil-steel structure's characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  3. The Spontaneous Combustion of Railway Ties and Asphalt Shingles

    Science.gov (United States)

    Leslie, Geoffrey

    Many Low Carbon Fuels (LCFs) present unknown spontaneous combustion risks, which must be quantified before their use as fossil fuel replacements. Wood and coal spontaneous combustion is well understood; however, LCFs weather, and subsequent chemical changes could affect their spontaneous combustion properties. LCF spontaneous combustion could lead to accidental fires with possible loss of life, limb and property. The spontaneous combustion risks of two LCFs, discarded creosote-treated wooden railway ties and roofing asphalt shingles, were investigated with calorimetry and heat transfer experiments. Chemical changes due to weathering were studied with pyrolysis-Gas Chromatography/Mass Spectrometry (py-GC/MS). Creosote-treated wooden railway tie dust, roofing asphalt shingle particles, poplar wood pellets, and petroleum coke self-heating were studied with isothermal calorimetry. Railway tie dust and asphalt shingle heat transfer were characterized with a guarded hot plate. Petroleum coke self-heating was consistent with coal, while both poplar pellets and railway tie dust were found to be more reactive compared to oven test results of similar materials. The observed increase in reactivity was probably a result of significant moisture contenint in the pellet and railway tie dust. Critical conditions for spontaneous combustion were evaluated with the Frank-Kamenetskii parameter, assuming an ambient temperature of 40°C and constant moisture content. Kamenetskii calculations indicate that a 1.6 m cube of railway tie dust, or a 58 m cube of asphalt particles, would be unstable and combust. LCF chemistry may have been affected by weathering, which would cause chemical changes that affect their spontaneous combustion properties. Therefore, railway tie wood and roofing asphalt shingle chemistry were investigated by identifying products of 250° and 550°C pyrolysis with py-GC/MS. Railway tie wood pyrolyzates did not show signs of weathering; in contrast, asphalt pyrolysis

  4. Railway clearance intrusion detection method with binocular stereo vision

    Science.gov (United States)

    Zhou, Xingfang; Guo, Baoqing; Wei, Wei

    2018-03-01

    In the stage of railway construction and operation, objects intruding railway clearance greatly threaten the safety of railway operation. Real-time intrusion detection is of great importance. For the shortcomings of depth insensitive and shadow interference of single image method, an intrusion detection method with binocular stereo vision is proposed to reconstruct the 3D scene for locating the objects and judging clearance intrusion. The binocular cameras are calibrated with Zhang Zhengyou's method. In order to improve the 3D reconstruction speed, a suspicious region is firstly determined by background difference method of a single camera's image sequences. The image rectification, stereo matching and 3D reconstruction process are only executed when there is a suspicious region. A transformation matrix from Camera Coordinate System(CCS) to Track Coordinate System(TCS) is computed with gauge constant and used to transfer the 3D point clouds into the TCS, then the 3D point clouds are used to calculate the object position and intrusion in TCS. The experiments in railway scene show that the position precision is better than 10mm. It is an effective way for clearance intrusion detection and can satisfy the requirement of railway application.

  5. Power-Electronics Issues of Modern Electric Railway Systems

    Directory of Open Access Journals (Sweden)

    STEIMEL, A.

    2010-05-01

    Full Text Available After de-regulation of the former state-owned railways and severe restructuring of the railway industry in the last 15 years, more innovative vehicle concepts saw the light of the day. Power electronics, already formerly being a pacemaker for progress of traction vehicles, brought forth an utmost standardization of the main drive by means of the IGBT-converter-fed induction motor drive. This is independent of the railway supply voltage system or of a diesel prime mover, for locomotives, high-speed and mass-transit trains as well as for tramways. Vehicles able to operate on all four European railway voltage systems have become feasible and are used now widely. New trends as Permanent-Magnet Synchronous Motors or Medium-Frequency Transformers are discussed, and a short overlook over actual field-oriented high-performance motor control systems - including a speed-sensorless variant - is given. Power electronics dominates the field of conversion of the 16.7-Hz railway supply power, typical for Central Europe, from the 50-Hz three-phase utility grid.

  6. Integrity Evaluation of Railway Bogie Using Infrared Thermography Technique

    International Nuclear Information System (INIS)

    Kim, Jeong Guk

    2011-01-01

    The lock-in thermography was employed to evaluate the integrity of railway bogies. Prior to the actual application on railway bogies, in order to assess the detectability of known flaws, the calibration reference panel was prepared with various dimensions of artificial flaws. The panel was composed of structural steel, which was the same material with actual bogies. Through lock-in thermography evaluation, the optimal frequency of heat source was determined for the best flaw detection. Based on the defects information, the actual defect assessments on railway bogie were conducted with different types of railway bogies, which were used for the current operation. In summary, the defect assessment results with thermography method showed a good agreement as compared with the conventional inspection techniques. Moreover, it was found that the novel infrared thermography technique could be an effective way for the inspection and the detection of surface defects on bogies since the infrared thermography method provided rapid and non-contact mode for the investigation of railway bogies

  7. Energetic optimization of regenerative braking for high speed railway systems

    International Nuclear Information System (INIS)

    Frilli, Amedeo; Meli, Enrico; Nocciolini, Daniele; Pugi, Luca; Rindi, Andrea

    2016-01-01

    Highlights: • A model of longitudinal dynamics of the High-speed train ETR1000 is presented. • The model includes on board traction and braking subsystems. • Interactions between overhead line and power line are modelled. • The model is validated on real experimental data. • An energy storage strategy for a high-speed line is proposed. - Abstract: The current development trend in the railway field has led to an ever increasing interest for the energetic optimization of railway systems (especially considering the braking phases), with a strong attention to the mutual interactions between the loads represented by railway vehicles and the electrical infrastructure, including all the sub-systems related to distribution and smart energy management such as energy storage systems. In this research work, the authors developed an innovative coupled modelling approach suitable for the analysis of the energetic optimization of railway systems and based on the use of the new object oriented language Matlab-Simscape™, which presents several advantages with respect to conventional modelling tools. The proposed model has been validated considering an Italian Direct Current High-speed line and the High-speed train ETR 1000. Furthermore, the model has been used to perform an efficiency analysis, considering the use of energy storage devices. The results obtained with the developed model show that the use of energy recovery systems in high-speed railway can provide great opportunities of energy savings.

  8. A comparison of two exact methods for passenger railway rolling stock (re)scheduling

    DEFF Research Database (Denmark)

    Haahr, Jørgen Thorlund; Wagenaar, Joris C.; Veelenturf, Lucas P.

    2016-01-01

    The assignment of rolling stock units to timetable services in passenger railways is an important optimization problem that has been addressed by many papers in different forms. Solution approaches have been proposed for different planning phases: strategic, tactical, operational, and real...... is solved using a column and row generation approach. In this paper, we benchmark the performance of the methods on networks of two countries (Denmark and The Netherlands). We use the approaches to make daily schedules and we test their real time applicability by performing tests with different disruption...... scenarios. The computational experiments demonstrate that both models can be used on both networks and are able to find optimal rolling stock circulations in the different planning phases. Furthermore, the results show that both approaches are sufficiently fast to be used in a real-time setting....

  9. Developing a Mathematical Model for Scheduling and Determining Success Probability of Research Projects Considering Complex-Fuzzy Networks

    Directory of Open Access Journals (Sweden)

    Gholamreza Norouzi

    2015-01-01

    Full Text Available In project management context, time management is one of the most important factors affecting project success. This paper proposes a new method to solve research project scheduling problems (RPSP containing Fuzzy Graphical Evaluation and Review Technique (FGERT networks. Through the deliverables of this method, a proper estimation of project completion time (PCT and success probability can be achieved. So algorithms were developed to cover all features of the problem based on three main parameters “duration, occurrence probability, and success probability.” These developed algorithms were known as PR-FGERT (Parallel and Reversible-Fuzzy GERT networks. The main provided framework includes simplifying the network of project and taking regular steps to determine PCT and success probability. Simplifications include (1 equivalent making of parallel and series branches in fuzzy network considering the concepts of probabilistic nodes, (2 equivalent making of delay or reversible-to-itself branches and impact of changing the parameters of time and probability based on removing related branches, (3 equivalent making of simple and complex loops, and (4 an algorithm that was provided to resolve no-loop fuzzy network, after equivalent making. Finally, the performance of models was compared with existing methods. The results showed proper and real performance of models in comparison with existing methods.

  10. Impact of high-speed railway accessibility on the location choices of office establishments

    NARCIS (Netherlands)

    Willigers, J.

    2006-01-01

    High-speed railways are becoming increasingly common in Europe. In the Netherlands soon the HSL-South will be opened. This high-speed railway line connects the Randstad to Brussels and Paris. A prominent aim of this new railway is to improve international competitiveness of the Netherlands. As a

  11. 78 FR 41993 - Ann Arbor Railroad, Inc.-Lease Exemption-Norfolk Southern Railway Company

    Science.gov (United States)

    2013-07-12

    ... number of carloads interchanged with NSR in a given year.\\1\\ AARR states that the interchange commitment..., Canadian National Railway Company (CN), CSX Transportation, Inc., and Wheeling & Lake Erie Railway in Toledo; the Indiana and Ohio Railway and CN in Diann, Mich.; NSR in Milan, Mich.; and Great Lakes Central...

  12. Passenger oriented railway disruption management by adapting timetables and rolling stock schedules

    NARCIS (Netherlands)

    Veelenturf, L.P.; Kroon, L.G.; Maróti, G.

    2017-01-01

    In passenger railway operations, unforeseen events require railway operators to adjust their timetable and their resource schedules. The passengers will also adapt their routes to their destinations. When determining the new timetable and rolling stock schedule, the railway operator has to take

  13. Safety motion increase of trains by improvement diagnostics process devices of railway automation

    Directory of Open Access Journals (Sweden)

    B.M.Bondarenko

    2012-12-01

    Full Text Available The complex use of methods of nondestructive check for the automated diagnostics electromagnetic relays of railway automation the first class reliability is offered. The methods determination of their mechanical parameters are resulted, that allows to exclude a human factor from the control, promote reliability of devices railway automation and safety motion of railway transport.

  14. Mathematical Footprints Discovering Mathematics Everywhere

    CERN Document Server

    Pappas, Theoni

    1999-01-01

    MATHEMATICAL FOOTPRINTS takes a creative look at the role mathematics has played since prehistoric times, and will play in the future, and uncovers mathematics where you least expect to find it from its many uses in medicine, the sciences, and its appearance in art to its patterns in nature and its central role in the development of computers. Pappas presents mathematical ideas in a readable non-threatening manner. MATHEMATICAL FOOTPRINTS is another gem by the creator of THE MATHEMATICS CALENDAR and author of THE JOY OF MATHEMATICS. "Pappas's books have been gold mines of mathematical ent

  15. A Network for Integrated Science and Mathematics Teaching and Learning Conference Plenary Papers. NSF/SSMA Wingspread Conference (Racine, Wisconsin, April 1991). School Science and Mathematics Association Topics for Teachers Series Number 7.

    Science.gov (United States)

    Berlin, Donna F., Ed.

    The integration of mathematics and science is not a new concept. However, during recent years it has been a major focus in education reform. A Wingspread conference promoted discussion regarding the integration of mathematics and science and explored ways to improve science and mathematics education in grades K-12. Papers from the conference…

  16. Road Traffic and Railway Noise Exposures and Adiposity in Adults

    DEFF Research Database (Denmark)

    Christensen, Jeppe S; Raaschou-Nielsen, Ole; Tjønneland, Anne

    2016-01-01

    and railway noise and adiposity. METHODS: In this cross-sectional study of 57,053 middle-aged people, height, weight, waist circumference, and bioelectrical impedance were measured at enrollment (1993-1997). Body mass index (BMI), body fat mass index (BFMI), and lean body mass index (LBMI) were calculated....... Residential exposure to road and railway traffic noise exposure was calculated using the Nordic prediction method. Associations between traffic noise and anthropometric measures at enrollment were analyzed using general linear models and logistic regression adjusted for demographic and lifestyle factors......, significant increases were also found for BFMI and LBMI. All associations followed linear exposure-response relationships. Exposure to railway noise was not linearly associated with adiposity measures. However, exposure > 60 dB was associated with a 0.71-cm wider waist circumference (95% CI: 0.23, 1...

  17. Approaches for reducing structural vibration of the carbody railway vehicles

    Directory of Open Access Journals (Sweden)

    Dumitriu Mădălina

    2017-01-01

    Full Text Available Reducing the weight of the railway vehicles stands as a decisive rule in their design, entailed by higher velocities, the need to consume less energy and lower the manufacturing costs, along with the maximization of the use of loads on the axle. Once complied with this rule, the vehicle flexibility increases and leads to an easy excitation of the structural vibrations in the carbody, with an impact upon the ride comfort in the railway vehicle. For a better ride comfort in lightweight railway vehicles, both vibration isolation approaches and structural damping approaches have been introduced. The paper herein submits a brief review of the main structural damping approaches aiming to reduce the amplitude in the carbody structural vibrations, based on the use of the piezoelectric elements in passive control schemes. The paper outcomes show the potential of the presented methods concerning the reduction of the flexible vibrations in the carbody and the ride comfort improvement.

  18. Study of Drivers’ Behaviour at a Passive Railway Crossing

    Directory of Open Access Journals (Sweden)

    Sandra Kasalica

    2012-05-01

    Full Text Available Problem: The number of killed and injured persons in incidents at railway level crossings is generally increasing on the Serbian Railways, particularly at passive crossings. In this paper we researched the direct behaviour of road traffic participants at a conventional railway passive crossing. Method: Direct observational study of drivers’ behaviour at a level crossing. Results: Sixty-one road vehicle drivers were observed in the moments of train approach. The probability of crossing varies depending on the train distance and the time the driver has to cross the crossing. The drivers who have limited visibility cannot estimate the speed of the approaching train well and make more risky decisions. Conclusion: This study shows that the number of “risky crossings” is worrying as the result of such crossings is a large number of accidents with fatal consequences at the passive crossings in Serbia.

  19. A cascading failure model for analyzing railway accident causation

    Science.gov (United States)

    Liu, Jin-Tao; Li, Ke-Ping

    2018-01-01

    In this paper, a new cascading failure model is proposed for quantitatively analyzing the railway accident causation. In the model, the loads of nodes are redistributed according to the strength of the causal relationships between the nodes. By analyzing the actual situation of the existing prevention measures, a critical threshold of the load parameter in the model is obtained. To verify the effectiveness of the proposed cascading model, simulation experiments of a train collision accident are performed. The results show that the cascading failure model can describe the cascading process of the railway accident more accurately than the previous models, and can quantitatively analyze the sensitivities and the influence of the causes. In conclusion, this model can assist us to reveal the latent rules of accident causation to reduce the occurrence of railway accidents.

  20. Kronecker Algebra-based Deadlock Analysis for Railway Systems

    Directory of Open Access Journals (Sweden)

    Robert Mittermayr

    2012-09-01

    Full Text Available Deadlock analysis for railway systems differs in several aspects from deadlock analysis in computer science. While the problem of deadlock analysis for standard computer systems is well-understood, multi-threaded embedded computer systems pose new challenges. A novel approach in this area can easily be applied to deadlock analysis in the domain of railway systems. The approach is based on Kronecker algebra. A lazy implementation of the matrix operations even allows analysing exponentially sized systems in a very efficient manner. The running time of the algorithm does not depend on the problem size but on the size of the solution. While other approaches suffer from the fact that additional constraints make the problem and its solution harder, our approach delivers its results faster if constraints are added. In addition, our approach is complete and sound for railway systems, i.e., it generates neither false positives nor false negatives.

  1. AUTOMATIC RAILWAY POWER LINE EXTRACTION USING MOBILE LASER SCANNING DATA

    Directory of Open Access Journals (Sweden)

    S. Zhang

    2016-06-01

    Full Text Available Research on power line extraction technology using mobile laser point clouds has important practical significance on railway power lines patrol work. In this paper, we presents a new method for automatic extracting railway power line from MLS (Mobile Laser Scanning data. Firstly, according to the spatial structure characteristics of power-line and trajectory, the significant data is segmented piecewise. Then, use the self-adaptive space region growing method to extract power lines parallel with rails. Finally use PCA (Principal Components Analysis combine with information entropy theory method to judge a section of the power line whether is junction or not and which type of junction it belongs to. The least squares fitting algorithm is introduced to model the power line. An evaluation of the proposed method over a complicated railway point clouds acquired by a RIEGL VMX450 MLS system shows that the proposed method is promising.

  2. A comparative study of performance measurement standards of railway operator

    Directory of Open Access Journals (Sweden)

    Pongjirawut Siripong

    2017-01-01

    Full Text Available The European standard (EN 13816, is one of the widely accepted standards for measuring the quality of public passenger transport (PPT service. EN 13816 indicates 8 measurement criteria, 29 sub-criteria and 193 Key Performance Indicators (KPIs to be used to measure the performance of railway operators. Nowadays, there are other addition criteria beyond EN13816, developed by various organisations. This research firstly aims to explore the service performance measurement of railway operators used by actual railway operators at international level and in Thailand. After an intensive review of performance measurement standards, 9 standards are compiled and compared in terms of criteria, sub-criteria and KPIs using a cluster analysis methodology. The result found additional performance measurement aspects at 2 sub-criteria and 91 KPIs in addition to EN 13816. This research summarized and compared different performance measurement standards to measure service quality of metro rail line.

  3. Seismic impact of the railway on the geotechnical constructions

    Science.gov (United States)

    Stolárik, Martin; Pinka, Miroslav

    2017-09-01

    Nowadays, the focus on more ecological means of material and persons transport is still higher. Big loads can be transported on railways more effectively and with lower environment impact than on roads. The geotechnical structures are inherent parts of railway infrastructure, such as embankments, sides of notches and, of course, tunnels, foundation constructions of buildings or pillars of bridges and the others geotechnical constructions (e.g. retaining walls, culverts, transition area of bridges). By train pass, vibrations are caused and these vibrations are relayed to the soil. These vibrations can make adverse impact to surrounding objects and to technologies placed in. This so far uncared-for influence gets into the foreground by current trend of everyday life technical equipment increasing. The article introduces different kinds of geotechnical structures and the influence of by-passing railway transport on their constructions and surroundings. The data are evaluated in the amplitude and frequency domain.

  4. Applied impulsive mathematical models

    CERN Document Server

    Stamova, Ivanka

    2016-01-01

    Using the theory of impulsive differential equations, this book focuses on mathematical models which reflect current research in biology, population dynamics, neural networks and economics. The authors provide the basic background from the fundamental theory and give a systematic exposition of recent results related to the qualitative analysis of impulsive mathematical models. Consisting of six chapters, the book presents many applicable techniques, making them available in a single source easily accessible to researchers interested in mathematical models and their applications. Serving as a valuable reference, this text is addressed to a wide audience of professionals, including mathematicians, applied researchers and practitioners.

  5. mathematical models for estimating radio channels utilization

    African Journals Online (AJOL)

    2017-08-08

    Aug 8, 2017 ... Mathematical models for radio channels utilization assessment by real-time flows transfer in ... data transmission networks application having dynamic topology ..... Journal of Applied Mathematics and Statistics, 56(2): 85–90.

  6. Analysis of the monitoring data of geomagnetic storm interference in the electrification system of a high-speed railway

    Science.gov (United States)

    Liu, Lianguang; Ge, Xiaoning; Zong, Wei; Zhou, You; Liu, Mingguang

    2016-10-01

    To study the impact of geomagnetic storm on the equipment of traction electrification system in the high-speed railway, geomagnetically induced current (GIC) monitoring devices were installed in the Hebi East traction power supply substation of the Beijing-Hong Kong Dedicated Passenger Line in January 2015, and GICs were captured during the two geomagnetic storms on 17 March and 23 June 2015. In order to investigate the GIC flow path, both in the track circuit and in the traction network adopting the autotransformer feeding system, a GIC monitor plan was proposed for the electrical system in the Hebi East traction power supply substation. This paper analyzes the correlation between the GIC captured on 17 March and the geomagnetic data obtained from the Malingshan Geomagnetic Observatory and presents a regression analysis between the measured GIC and the calculated geoelectric fields on 23 June in the high-speed railway. The maximum GICs measured in the track circuit are 1.08 A and 1.74 A during the two geomagnetic storms. We find that it is necessary to pay attention on the throttle transformers and track circuits, as the most sensitive elements responding to the extreme geomagnetic storms in the high-speed railway.

  7. Historical flora of Moscow’s Railway Junction (until 2012

    Directory of Open Access Journals (Sweden)

    Vinogradova Yulia Konstantinovna

    2017-12-01

    Full Text Available The article touches upon the biodiversity at the railways. The list of species found within the Moscow Railways (≈300 km from 1851 until today has been compiled based on herbarium data [MHA, MW, LE] and personal observations conducted in 1980-2016. The list of “railways’ flora” includes 1087 taxa from 447 genera of 94 families – this is significantly higher than what is known for the railroads of other regions. A brief comparative analysis with the “railways’ flora” in other regions of the world in respect of the species number, taxonomy and life form spectrum has been performed. The therophytes absolutely prevail in the life-form spectrum (46 percent. The role of the railways as a pathway for alien species has been confirmed. Around 54 percent of all alien plants recorded for the Moscow Region (Moscow and Moscow Region grow along the railways. Several species new for the former USSR territory was found there, as well as many species new for the Moscow Region. The Railways are not only “donors/sources” of alien species, they also act as a refugee area for “the escapees”: over 30 years, Asclepias syriaca has been growing within the section of the Kursk-Moscow railway located near the All-Russian Research Institute of Medical and Aromatic Plants. Galega officinalis, a specie that forms a 200 m2 area of tangled vegetation, was found there, too. A trend when plants fall out of cultivation was established, this is how Sedum hispanicum and S. album emerged. The article also marks the role of the rail slopes as a refugium of rare and endangered plants of the natural flora: some 35 species included in the Red Book of Moscow were found within the area.

  8. Big data for risk analysis: The future of safe railways

    Energy Technology Data Exchange (ETDEWEB)

    Figueres Esteban, M.

    2016-07-01

    New technology brings ever more data to support decision-making for intelligent transport systems. Big Data is no longer a futuristic challenge, it is happening right now: modern railway systems have countless sources of data providing a massive quantity of diverse information on every aspect of operations such as train position and speed, brake applications, passenger numbers, status of the signaling system or reported incidents.The traditional approaches to safety management on the railways have relied on static data sources to populate traditional safety tools such as bow-tie models and fault trees. The Big Data Risk Analysis (BDRA) program for Railways at the University of Huddersfield is investigating how the many Big Data sources from the railway can be combined in a meaningful way to provide a better understanding about the GB railway systems and the environment within which they operate.Moving to BDRA is not simply a matter of scaling-up existing analysis techniques. BDRA has to coordinate and combine a wide range of sources with different types of data and accuracy, and that is not straight-forward. BDRA is structured around three components: data, ontology and visualisation. Each of these components is critical to support the overall framework. This paper describes how these three components are used to get safety knowledge from two data sources by means of ontologies from text documents. This is a part of the ongoing BDRA research that is looking at integrating many large and varied data sources to support railway safety and decision-makers. (Author)

  9. An Analytical Design Method for a Regenerative Braking Control System for DC-electrified Railway Systems under Light Load Conditions

    Science.gov (United States)

    Saito, Tatsuhito; Kondo, Keiichiro; Koseki, Takafumi

    A DC-electrified railway system that is fed by diode rectifiers at a substation is unable to return the electric power to an AC grid. Accordingly, the braking cars have to restrict regenerative braking power when the power consumption of the powering cars is not sufficient. However, the characteristics of a DC-electrified railway system, including the powering cars, is not known, and a mathematical model for designing a controller has not been established yet. Hence, the object of this study is to obtain the mathematical model for an analytical design method of the regenerative braking control system. In the first part of this paper, the static characteristics of this system are presented to show the position of the equilibrium point. The linearization of this system at the equilibrium point is then performed to describe the dynamic characteristics of the system. An analytical design method is then proposed on the basis of these characteristics. The proposed design method is verified by experimental tests with a 1kW class miniature model, and numerical simulations.

  10. EVALUATION OF ALTERNATIVE RAILWAY CONNECTION ACCESS AT JAKARTA SOEKARNO HATTA INTERNATIONAL AIRPORT

    Directory of Open Access Journals (Sweden)

    Ayu Aprilischa

    2015-01-01

    Full Text Available Traveling between the center of Jakarta and Soekarno Hatta International Airport (SHIA is further constrained by the limited number of main routes available which likely cannot be accommodated in the future by road based transport modes alone. Hence, the airport needs to develop airport surface access to accommodate its network. The aim of this research is to analyze the railway access system for developing the system of SHIA using multi criteria analysis in the selection of alternative route alignment of the railway line and a qualitative study in data collection within the research design. Development of the criteria includes technical, economic, environmental and spatial aspect. Three alternatives have been proposed in this analysis, i.e. through West Jakarta, through North and West Jakarta and through North and Central Jakarta. The results show that alternative 3 (through North and Central Jakarta can give implications to the airport users, i.e. providing a high standard of the rail link in a well-timed manner and a cost-effective public transport link. Improving the multi-modal access to the airport will improve the supply of employment to business, lead to urban regeneration around station locations, and improve Greater Jakarta Metropolitan Area regional competitiveness.

  11. One for all: workplace social context and drinking among railway workers in Ukraine.

    Science.gov (United States)

    Murphy, Adrianna; Roberts, Bayard; McGowan, Catherine; Kizilova, Kseniya; Kizilov, Alexiy; Rhodes, Tim; McKee, Martin

    2015-01-01

    Alcohol consumption is a leading cause of mortality and morbidity in countries of the former Soviet Union, but little is known about its social determinants. Recent research has suggested that workplace contexts may play a role. Using qualitative methods, we investigate the relationship between workplace social contexts and drinking in Ukraine. We conducted 24 individual semi-structured interviews and two focus group discussions in Lviv and Kharkiv, Ukraine, with male railway employees aged 18+ years. Data were analysed using a thematic analysis approach. Men in our sample expressed strong feelings of interdependence and trust towards their co-workers which we defined as 'social solidarity'. Drinking with co-workers was often seen as obligatory and an integral part of co-worker social occasions. Engagement in sport or family obligations seemed to act as a deterrent to drinking among some workers. A strong sense of solidarity exists between railway co-workers in Ukraine, perhaps a remnant of the Soviet era when individuals relied on informal networks for support. Alcohol may be used as a means of expressing this solidarity. Our findings point to factors, namely engagement in sports and family, which may offer opportunities for interventions to reduce alcohol consumption among workers in Ukraine.

  12. Vulnerability analysis of complementary transportation systems with applications to railway and airline systems in China

    International Nuclear Information System (INIS)

    Ouyang, Min; Pan, ZheZhe; Hong, Liu; He, Yue

    2015-01-01

    Most of existing studies on vulnerability analysis of multiple infrastructure systems mainly focus on negative effects of interdependencies, which mean that failures in one system can propagate to other systems and aggravate the initial damage. In reality, there also exist positive effects of interdependencies, which are shown in complementary systems and mean that if one system fails another system can provide alternative services to satisfy customers' demands. Different types of transportation systems in a city or country are typical complementary systems. Taking railway and airline systems in China as an example, this paper proposes a network-based approach to model the vulnerability of complementary transportation systems, and based on this model, this paper further introduces a dynamic complementary strength metric, which can help decision makers design or select better complementary topologies from the vulnerability perspective. Also, based on a simple genetic algorithm, this paper analyzes whether critical components for single systems are still important when taking two systems as a whole for analysis. Results show that a protection strategy of hardening a few critical components is also good strategy for the combined system. In addition, the findings and several assumptions are further discussed to close the gap between theory and practice. - Highlights: • We propose a method to model and analyze complementary system vulnerability. • We study vulnerability of complementary railway and airline systems in China. • We propose an approach to quantify dynamic complementary strength. • A few critical components for single systems are important for combined system

  13. Dynamics of a railway vehicle on a laterally disturbed track

    DEFF Research Database (Denmark)

    Christiansen, Lasse Engbo; True, Hans

    2017-01-01

    In this article a theoretical investigation of the dynamics of a railway bogie running on a tangent track with a periodic disturbance of the lateral track geometry is presented. The dynamics is computed for two values of the speed of the vehicle in combination with different values of the wavelen......In this article a theoretical investigation of the dynamics of a railway bogie running on a tangent track with a periodic disturbance of the lateral track geometry is presented. The dynamics is computed for two values of the speed of the vehicle in combination with different values...

  14. A codimension two bifurcation in a railway bogie system

    DEFF Research Database (Denmark)

    Zhang, Tingting; True, Hans; Dai, Huanyun

    2017-01-01

    In this paper, a comprehensive analysis is presented to investigate a codimension two bifurcation that exists in a nonlinear railway bogie dynamic system combining theoretical analysis with numerical investigation. By using the running velocity V and the primary longitudinal stiffness (Formula...... coexist in a range of the bifurcation parameters which can lead to jumps in the lateral oscillation amplitude of the railway bogie system. Furthermore, reduce the values of the bifurcation parameters gradually. Firstly, the supercritical Hopf bifurcation turns into a subcritical one with multiple limit...

  15. Development of prototype DC superconducting cable for railway system

    International Nuclear Information System (INIS)

    Tomita, Masaru; Fukumoto, Yusuke; Suzuki, Kenji; Miryala, Muralidhar

    2010-01-01

    High Temperature Superconducting (HTSC) wire has significant potential for railway system applications. HTSC wire is currently a promising candidate for various engineering applications such as transformers and motors for railway system. HTSC direct current (DC) cable is ideal for a feeder of the overhead contact line system between the substation and the electric train. We completed a prototype Bi-2223 tape based direct current cable for trial purposes of several meters length. In the energizing experiment the current of 1720 A successfully constantly flew.

  16. Dynamics of railway bridges, analysis and verification by field tests

    Directory of Open Access Journals (Sweden)

    Andersson Andreas

    2015-01-01

    Full Text Available The following paper discusses different aspects of railway bridge dynamics, comprising analysis, modelling procedures and experimental testing. The importance of realistic models is discussed, especially regarding boundary conditions, load distribution and soil-structure interaction. Two theoretical case studies are presented, involving both deterministic and probabilistic assessment of a large number of railway bridges using simplified and computationally efficient models. A total of four experimental case studies are also introduced, illustrating different aspects and phenomena in bridge dynamics. The excitation consists of both ambient vibrations, train induced vibrations, free vibrations after train passages and controlled forced excitation.

  17. Viscoelastic dynamic models of resilient elements used in railway tracks

    Directory of Open Access Journals (Sweden)

    Zbiciak Artur

    2016-01-01

    Full Text Available The paper presents selected theoretical aspects concerning viscoelastic dynamic modelling of resilient elements used in railway tracks. In order to characterize the research methodology for resilient mats in railway tracks, German Standards [1-4] are used herein. The main goal of the paper is to demonstrate the procedure of insertion loss calculation for a single degree of freedom truck system containing under-ballast mats. Selected results of certain dynamic characteristics of resilient truck systems (transmissibility, Bode and Nyquist plots etc. are also discussed. The results of calculations visualized in graphs, were obtained by using own applications written in programming language MATLAB.

  18. Novel method for edge detection of retinal vessels based on the model of the retinal vascular network and mathematical morphology

    Science.gov (United States)

    Xu, Lei; Zheng, Xiaoxiang; Zhang, Hengyi; Yu, Yajun

    1998-09-01

    Accurate edge detection of retinal vessels is a prerequisite for quantitative analysis of subtle morphological changes of retinal vessels under different pathological conditions. A novel method for edge detection of retinal vessels is presented in this paper. Methods: (1) Wavelet-based image preprocessing. (2) The signed edge detection algorithm and mathematical morphological operation are applied to get the approximate regions that contain retinal vessels. (3) By convolving the preprocessed image with a LoG operator only on the detected approximate regions of retinal vessels, followed by edges refining, clear edge maps of the retinal vessels are fast obtained. Results: A detailed performance evaluation together with the existing techniques is given to demonstrate the strong features of our method. Conclusions: True edge locations of retinal vessels can be fast detected with continuous structures of retinal vessels, less non- vessel segments left and insensitivity to noise. The method is also suitable for other application fields such as road edge detection.

  19. Research of noise emission sources in railway transport and effective ways of their reduction

    Directory of Open Access Journals (Sweden)

    Zvolenský Peter

    2017-01-01

    Full Text Available In the EU conditions attention is systematically paid to noise reduction on the railways. Because TSI rules systematically tighten limits for noise emissions from railway vehicles, noise research must be addressed by all Member States, as the main technical solutions for railway vehicles and construction technological aspects of railway operations can result in lower noise exposure of affected areas or objects. The paper focuses on theoretical investigation of sources and paths of sound propagation, possibilities of noise reduction both on vehicles and by infrastructure and experimental measurements of the situation in transport practice. Methodology for reducing railway noise around tracks has been presented, too.

  20. Railway infrastructure monitoring with COSMO/SkyMed imagery and multi-temporal SAR interferometry

    Science.gov (United States)

    Chiaradia, M.; Nutricato, R.; Nitti, D. O.; Bovenga, F.; Guerriero, L.

    2012-12-01

    For all the European Countries, the rail network represents a key critical infrastructure, deserving protection in view of its continuous structure spread over the whole territory, of the high number of European citizens using it for personal and professional reasons, and of the large volume of freight moving through it. Railway system traverses a wide variety of terrains and encounters a range of geo-technical conditions. The interaction of these factors together with climatic and seismic forcing, may produce ground instabilities that impact on the safety and efficiency of rail operations. In such context, a particular interest is directed to the development of technologies regarding both the prevention of mishaps of infrastructures and the fast recovery of their normal working conditions after the occurrence of accidents (disaster managing). Both these issues are of strategic interest for EU Countries, and in particular for Italy, since, more than other countries, it is characterized by a geo-morphological and hydro-geological structure complexity that increases the risk of natural catastrophes due to landslides, overflowings and floods. The present study has been carried out in the framework of a scientific project aimed at producing a diagnostic system, capable to foresee and monitor landslide events along railway networks by integrating in situ data, detected from on board sophisticated innovative measuring systems, with Earth Observation (EO) techniques. Particular importance is devoted to the use of advanced SAR interferometry, thanks to their all-weather, day-night capability to detect and measure with sub-centimeter accuracy ground surface displacements that, in such context, can occur before a landslide event or after that movements . Special attention is directed to the use of SAR images acquired by COSMO/SkyMed (ASI) constellation capable to achieve very high spatial resolution and very short revisit and response time. In this context, a stack of 57 CSK

  1. A mathematical/physics carbon emission reduction strategy for building supply chain network based on carbon tax policy

    Directory of Open Access Journals (Sweden)

    Li Xueying

    2017-03-01

    Full Text Available Under the background of a low carbon economy, this paper examines the impact of carbon tax policy on supply chain network emission reduction. The integer linear programming method is used to establish a supply chain network emission reduction such a model considers the cost of CO2 emissions, and analyses the impact of different carbon price on cost and carbon emissions in supply chains. The results show that the implementation of a carbon tax policy can reduce CO2 emissions in building supply chain, but the increase in carbon price does not produce a reduction effect, and may bring financial burden to the enterprise. This paper presents a reasonable carbon price range and provides decision makers with strategies towards realizing a low carbon building supply chain in an economical manner.

  2. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  3. INTELLECTUAL MODEL FORMATION OF RAILWAY STATION WORK DURING THE TRAIN OPERATION EXECUTION

    Directory of Open Access Journals (Sweden)

    O. V. Lavrukhin

    2014-11-01

    Full Text Available Purpose. The aim of this research work is to develop an intelligent technology for determination of the optimal route of freight trains administration on the basis of the technical and technological parameters. This will allow receiving the operational informed decisions by the station duty officer regarding to the train operation execution within the railway station. Metodology. The main elements of the research are the technical and technological parameters of the train station during the train operation. The methods of neural networks in order to form the self-teaching automated system were put in the basis of the generated model of train operation execution. Findings. The presented model of train operation execution at the railway station is realized on the basis of artificial neural networks using learning algorithm with a «teacher» in Matlab environment. The Matlab is also used for the immediate implementation of the intelligent automated control system of the train operation designed for the integration into the automated workplace of the duty station officer. The developed system is also useful to integrate on workplace of the traffic controller. This proposal is viable in case of the availability of centralized traffic control on the separate section of railway track. Originality. The model of train station operation during the train operation execution with elements of artificial intelligence was formed. It allows providing informed decisions to the station duty officer concerning a choice of rational and a safe option of reception and non-stop run of the trains with the ability of self-learning and adaptation to changing conditions. This condition is achieved by the principles of the neural network functioning. Practical value. The model of the intelligent system management of the process control for determining the optimal route receptionfor different categories of trains was formed.In the operational mode it offers the possibility

  4. Annoyance and activity disturbance induced by high-speed railway and conventional railway noise: a contrastive case study.

    Science.gov (United States)

    Di, Guo-Qing; Lin, Qi-Li; Li, Zheng-Guang; Kang, Jian

    2014-03-07

    High-speed railway (HR, Electrified railway with service speed above 200 km/h.) noise and conventional railway (CR, Electrified railway with service speed under 200 km/h.) noise are different in both time and frequency domain. There is an urgent need to study the influence of HR noise and consequently, develop appropriate noise evaluation index and limits for the total railway noise including HR and CR noise. Based on binaural recording of HR and CR noises in a approximate semi-free field, noise annoyance and activity disturbance induced by maximal train pass-by events in China were investigated through laboratory subjective evaluation. 80 students within recruited 102 students, 40 males and 40 females, 23.9 ± 2.1 years old, were finally selected as the subjects. After receiving noise stimulus via headphone of a binaural audio playback system, subjects were asked to express the annoyance or activity disturbance due to railway noise at a 0-100 numerical scale. The results show that with the same annoyance rating (A) or activity disturbance rating (D), the A-weighted equivalent sound pressure level (LAeq) of CR noise is approximately 7 dB higher than that of HR noise. Linear regression analysis between some acoustical parameters and A (or D) suggests that the coefficient of determination (R2) is higher with the instantaneous fast A-weighted sound pressure level (LAFmax) than that with LAeq. A combined acoustical parameter, LHC = 1.74LAFmax + 0.008LAFmax(Lp-LAeq), where Lp is the sound pressure level, was derived consequently, which could better evaluate the total railway noise, including HR and CR noise. More importantly, with a given LHC, the noise annoyance of HR and CR noise is the same. Among various acoustical parameters including LHC and LAeq, A and D have the highest correlation with LHC. LHC has been proved to be an appropriate index to evaluate the total railway noise, including both HR and CR. However, it should be pointed out that this study provides

  5. National Rail Network: 1:100,000 (line), Geographic WGS84, BTS (2006) [us_rail_network_100k_lin_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The Rail Network is a comprehensive database of the nation's railway system at the 1:100,000 scale. The data set covers all 50 States plus the District of Columbia.

  6. National Rail Network 1:2,000,000 (node), Geographic WGS84, BTS (2006) [us_rail_network_100k_nd_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The Rail Network is a comprehensive database of the nation's railway system at the 1:100,000 scale. The data set covers all 50 States plus the District of Columbia.

  7. Comparison of mathematical models and artificial neural networks for prediction of drying kinetics of mushroom in microwave vacuum dryer

    Directory of Open Access Journals (Sweden)

    Ghaderi A.

    2012-01-01

    Full Text Available Drying characteristics of button mushroom slices were determined using microwave vacuum drier at various powers (130, 260, 380, 450 W and absolute pressures (200, 400, 600, 800 mbar. To select a suitable mathematical model, 6 thin-layer drying models were fitted to the experimental data. The fitting rates of models were assessed based on three parameters; highest R2, lowest chi square ( and root mean square error (RMSE. In addition, using the experimental data, an ANN trained by standard back-propagation algorithm, was developed in order to predict moisture ratio (MR and drying rate (DR values based on the three input variables (drying time, absolute pressure, microwave power. Different activation functions and several rules were used to assess percentage error between the desired and the predicted values. According to our findings, Midilli et al. model showed a reasonable fitting with experimental data. While, the ANN model showed its high capability to predict the MR and DR quite well with determination coefficients (R2 of 0.9991, 0.9995 and 0.9996 for training, validation and testing, respectively. Furthermore, their predictions Mean Square Error were 0.00086, 0.00042 and 0.00052, respectively.

  8. Formal Development and Verification of a Distributed Railway Control System

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Peleska, Jan

    1999-01-01

    In this article we introduce the concept for a distributed railway control system and present the specification and verification of the main algorithm used for safe distributed control. Our design and verification approach is based on the RAISE method, starting with highly abstract algebraic...

  9. Dynamics of Railway Vehicles and Rail/Wheel Contact

    DEFF Research Database (Denmark)

    True, Hans

    2007-01-01

    of the most important dynamic effects on vehicle dynamic problems are described. In chapter 7 characteristic features of railway vehicle dynamics are described, and in chapter 8 recommendations are presented for the numerical handling that is necessary for the investigation of vehicle dynamic problems...

  10. Effective Development and Verification of Railway Control Software

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth

    2011-01-01

    This document presents a method for effective development of software for a product line of similar railway control systems. The software is constructed in three steps: first a specifications in a domain-specific language is created, then a formal behavioural controller model is automatically...

  11. Automated generation of formal safety conditions from railway interlocking tables

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth

    2014-01-01

    This paper describes a tool for extracting formal safety conditions from interlocking tables for railway interlocking systems. The tool has been applied to generate safety conditions for the interlocking system at Stenstrup station in Denmark, and the SAL model checker tool has been used to check...

  12. Detection of failures of axle-bearings of railway vehicles

    Directory of Open Access Journals (Sweden)

    Bižić Milan B.

    2016-01-01

    Full Text Available The failure of axle-bearing is one of the most common causes of derailments of railway vehicles which are usually accompanied by huge material damage and human casualties. Modern railways are working intensively on the development and implementation of appropriate systems for early detection of axlebearing malfunctions, which are typically manifested by increasing of its temperature. The most common approach is based on the use of wayside systems or checkpoints located in certain places along the track. There is also an innovative approach that involves using the system for continuous measuring and online monitoring of axle-boxes temperature. The main aim is to provide early detection of malfunctions of the axle-bearing and prevention of the potential derailment. This paper analyses the existing solutions for the detection of axle-bearings malfunctions with special emphasis on the working principle and the main advantages and disadvantages. The paper presents the basics of the one newly developed wireless measuring system for on-line monitoring of axle-boxes temperature. The measuring system was tested in real conditions and can be successfully applied to the commercial railway vehicles. The main conclusion is that systems for on-line monitoring of axle-bearings temperatures are far more efficient than wayside systems. Obtained results may be important for those who deal with these and similar problems, problems of development, exploitation and maintenance of railway vehicles, strategies, regulations, etc.

  13. A calculation model for the noise from steel railway bridges

    NARCIS (Netherlands)

    Janssens, M.H.A.; Thompson, D.J.

    1996-01-01

    The sound level of a train crossing a steel railway bridge is usually about 10 dB higher than on plain track. In the Netherlands there are many such bridges which, for practical reasons, cannot be replaced by more intrinsically quiet concrete bridges. A computational model is described for the

  14. Delay propagation and process management at railway stations

    NARCIS (Netherlands)

    Goverde, R.M.P.; Hansen, I.A.

    2001-01-01

    Process operators at large railway stations have the difficult task to secure a fluent train traffic flow while minimizing deviations from established timetables. Variation in actual train departure times is inevitable due to many circumstances such as arrival delays and fluctuations in alighting

  15. Strategy for predicting railway-induced vibrations in buildings

    DEFF Research Database (Denmark)

    Persson, Peter; Persson, Kent; Andersen, Lars Vabbersgaard

    2016-01-01

    Urban densification is a way of accommodating population growth. Land adjacent to railways is used for constructing residences and other buildings, and new tramway systems are planned. Under these circumstances, nearby buildings will be exposed to vibrations and noise that may become a nuisance...

  16. Developing resilience signals for the Dutch railway system

    NARCIS (Netherlands)

    Siegel, A.W.; Schraagen, Johannes Martinus Cornelis; Herrera, I.; Schraagen, J.M.C.; van der Vorm, J.; Woods, D.D.

    2014-01-01

    A resilience state model for a railway system is proposed consisting of three boundaries putting pressure on the operating state: Safety, Performance (Capacity & Punctuality) and Workload. In order to model the pressure of the boundaries, an additional dimension is added where the slope represents

  17. Railway Porters of Mumbai : Social Capital in Practice

    NARCIS (Netherlands)

    Weitering, D.; Nooteboom, G.

    2004-01-01

    This article explores the scope and limitations of social capital and local forms of social security in the informal sector through a case study of railway coolies at Dadar station, Mumbai. The complex organisation of the coolies, virtually excluded from state or enterprise social security schemes,

  18. Finding suspects in multiple cameras for improved railway protection

    NARCIS (Netherlands)

    Marck, J.W.; Bouma, H.; Baan, J; Oliveira Filho, J. de; Brink, M. van der

    2014-01-01

    The capability to find individuals using CCTV cameras is important for surveillance applications at large areas such as railway stations, airports and shopping centers. However, it is laborious to track and trace people over multiple cameras post incident. In this paper, we describe the live

  19. Sensitivity analysis of railpad parameters on vertical railway track dynamics

    NARCIS (Netherlands)

    Oregui Echeverria-Berreyarza, M.; Nunez Vicencio, Alfredo; Dollevoet, R.P.B.J.; Li, Z.

    2016-01-01

    This paper presents a sensitivity analysis of railpad parameters on vertical railway track dynamics, incorporating the nonlinear behavior of the fastening (i.e., downward forces compress the railpad whereas upward forces are resisted by the clamps). For this purpose, solid railpads, rail-railpad

  20. Organisational citizenship behaviour among railway employees in a ...

    African Journals Online (AJOL)

    This study investigated the effect of differences in age, education and tenure on organisational citizenship behaviour (OCB). The purposive sample comprised 839 permanently employed staff in a railway organisation in the Democratic Republic of Congo. Participants completed the Organisational Citizenship Behaviour ...

  1. Robustness in Railway Operations (RobustRailS)

    DEFF Research Database (Denmark)

    Jensen, Jens Parbo; Nielsen, Otto Anker

    This study considers the problem of enhancing railway timetable robustness without adding slack time, hence increasing the travel time. The approach integrates a transit assignment model to assess how passengers adapt their behaviour whenever operations are changed. First, the approach considers...

  2. Price Analysis of Railway Freight Transport under Marketing Mechanism

    Science.gov (United States)

    Shi, Ying; Fang, Xiaoping; Chen, Zhiya

    Regarding the problems in the reform of the railway tariff system and the pricing of the transport, by means of assaying the influence of the price elasticity on the artifice used for price, this article proposed multiple regressive model which analyzed price elasticity quantitatively. This model conclude multi-factors which influences on the price elasticity, such as the averagely railway freight charge, the averagely freight haulage of proximate supersede transportation mode, the GDP per capita in the point of origin, and a series of dummy variable which can reflect the features of some productive and consume demesne. It can calculate the price elasticity of different classes in different domains, and predict the freight traffic volume on different rate levels. It can calculate confidence-level, and evaluate the relevance of each parameter to get rid of irrelevant or little relevant variables. It supplied a good theoretical basis for directing the pricing of transport enterprises in market economic conditions, which is suitable for railway freight, passenger traffic and other transportation manner as well. SPSS (Statistical Package for the Social Science) software was used to calculate and analysis the example. This article realized the calculation by HYFX system(Ministry of Railways fund).

  3. Electrical injuries due to railway high tension cables.

    Science.gov (United States)

    Reichl, M; Kay, S

    1985-08-01

    We have noted a large number of young boys being admitted to our Unit with burns due to railway high tension cables. On review of these cases we have noted: most of the burns were due to arcing, there is a high level of ignorance among the population at risk. We propose some ways of preventing these injuries.

  4. Planning of resource maintenance at building of railway bridge

    Directory of Open Access Journals (Sweden)

    Klykov Michael

    2017-01-01

    Full Text Available The Publication contains the results of research on the problem of resources provision perfecting of erection processes of railway bridges including consideration of forecasting demand questions to material resources, formations of delivery schedules of materials and designs, definitions of insurance reserves in regards to suppliers of material and technical production.

  5. Experimental analysis of railway track settlement in transition zones

    NARCIS (Netherlands)

    Wang, H.; Markine, V.L.; Liu, X.

    2017-01-01

    Transition zones in railway tracks are the locations with considerable changes in the vertical support structures. Due to the differential stiffness and settlement in the open track and the engineering structure resulting in the dynamic amplification of the wheel forces, track settlement is usually

  6. Transparency and performance communication: a case study of Dutch Railways

    NARCIS (Netherlands)

    Galetzka, Mirjam; Gelders, Dave; Verckens, Jan Pieter; Seydel, E.R.

    2008-01-01

    Purpose – In an attempt to gain insight into the effects of transparent communication on critical performances, this paper aims to explore performance measures and communication of a large‐scale service organization, i.e. the Dutch Railways (Nederlandse Spoorwegen, (NS)). Design/methodology/approach

  7. Fatigue Properties of Orthotropic Decks on Railway Bridges

    Czech Academy of Sciences Publication Activity Database

    Frýba, Ladislav; Gajdoš, Lubomír

    1999-01-01

    Roč. 21, č. 7 (1999), s. 639-652 ISSN 0141-0296 Grant - others:XX(CZ) ERRI D 191 Keywords : railway bridges * orthotropic decks * fatigue Subject RIV: JM - Building Engineering Impact factor: 0.364, year: 1999

  8. Formal Verification of the Danish Railway Interlocking Systems

    DEFF Research Database (Denmark)

    Vu, Linh Hong; Haxthausen, Anne Elisabeth; Peleska, Jan

    2014-01-01

    in the new Danish interlocking systems. Instantiating the generic model with interlocking configuration data results in a concrete model and high-level safety properties. Using bounded model checking and inductive reasoning, we are able to verify safety properties for model instances corresponding to railway...

  9. Damage Detection in Railway Prestressed Concrete Sleepers using Acoustic Emission

    Science.gov (United States)

    Clark, A.; Kaewunruen, S.; Janeliukstis, R.; Papaelias, M.

    2017-10-01

    Prestressed concrete sleepers (or railroad ties) are safety-critical elements in railway tracks that distribute the wheel loads from the rails to the track support system. Over a period of time, the concrete sleepers age and deteriorate in addition to experiencing various types of static and dynamic loading conditions, which are attributable to train operations. In many cases, structural cracks can develop within the sleepers due to high intensity impact loads or due to poor track maintenance. Often, cracks of sleepers develop and present at the midspan due to excessive negative bending. These cracks can cause broken sleepers and sometimes called ‘center bound’ problem in railway lines. This paper is the world first to present an application of non-destructive acoustic emission technology for damage detection in railway concrete sleepers. It presents experimental investigations in order to detect center-bound cracks in railway prestressed concrete sleepers. Experimental laboratory testing involves three-point bending tests of four concrete sleepers. Three-point bending tests correspond to a real failure mode, when the loads are not transferred uniformly to the ballast support. It is observed that AE sensing provides an accurate means for detecting the location and magnitude of cracks in sleepers. Sensor location criticality is also highlighted in the paper to demonstrate the reliability-based damage detection of the sleepers.

  10. Formal Development and Verification of a Distributed Railway Control System

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Peleska, Jan

    1998-01-01

    In this article we introduce the concept for a distributed railway control system and present the specification and verification of the main algorithm used for safe distributed control. Our design and verification approach is based on the RAISE method, starting with highly abstract algebraic spec...

  11. Selection and testing of ballast stones for underground railway tracks

    African Journals Online (AJOL)

    Ballast is broken pieces of hard rocks such as sandstones, schist, etc. approximately 25- 60 mm size, over which the railway tracks are laid. The function of the ballast is to transfer the applied load over a large surface, provide adequate elasticity, prevent creep and hold the sleepers in position. Also under wet conditions, ...

  12. Mathematical modelling of ionospheric TEC from Turkish permanent GNSS Network (TPGN) observables during 2009-2017 and predictability of NeQuick and Kriging models

    Science.gov (United States)

    Ansari, Kutubuddin; Panda, Sampad Kumar; Corumluoglu, Ozsen

    2018-03-01

    The present study examines the ionospheric Total Electron Content (TEC) variations in the lower mid-latitude Turkish region from the Turkish permanent GNSS network (TPGN) and International GNSS Services (IGS) observations during the years 2009 to 2017. The corresponding vertical TEC (VTEC) predicted by Kriging and NeQuick-2 models are evaluated to realize their efficacy over the country. We studied the diurnal, seasonal and spatial pattern of VTEC variation and tried to estimate by a new mathematical model using the long term of 9 years VTEC data. The diurnal variation of VTEC demonstrates a normal trend with its gradual enhancement from dawn to attain a peak around 09:00-14.00 UT and reaching the minimum level after 22.00 UT. The seasonal behavior of VTEC indicates a strong semi-annual variation of VTEC with maxima in September equinox followed by March equinox and minima in June solstice followed by December solstice. Also, the spatial variation in VTEC depicts a meaningful longitudinal/latitudinal pattern altering with seasons. It decreases longitudinally from the west to the east during March equinox and June solstice increases with latitude. The comparative analysis among the GNSS-VTEC, Kriging, NeQuick and the proposed mathematical model are evaluated with the help one way ANOVA test. The analysis shows that the null hypothesis of the models during storm and quiet days are accepted and suggesting that all models are statistically significantly equivalent from each other. We believe the outcomes from this study would complement towards a relatively better understanding of the lower mid-latitude VTEC variation over the Turkish region and analogous latitudes over the globe.

  13. Mathematics disorder

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001534.htm Mathematics disorder To use the sharing features on this page, please enable JavaScript. Mathematics disorder is a condition in which a child's ...

  14. Mathematical Chemistry

    OpenAIRE

    Trinajstić, Nenad; Gutman, Ivan

    2002-01-01

    A brief description is given of the historical development of mathematics and chemistry. A path leading to the meeting of these two sciences is described. An attempt is made to define mathematical chemistry, and journals containing the term mathematical chemistry in their titles are noted. In conclusion, the statement is made that although chemistry is an experimental science aimed at preparing new compounds and materials, mathematics is very useful in chemistry, among other things, to produc...

  15. Rainforest Mathematics

    Science.gov (United States)

    Kilpatrick, Jeremy

    2014-01-01

    This paper addresses the contested way that ethnomathematics has sometimes been received by mathematicians and others and what that disagreement might suggest about issues in mathematics education; namely, (a) the relation of ethnomathematics to academic mathematics; (b) recent efforts to reform secondary school mathematics so that it prepares…

  16. AN AUTOMATED RAILWAY STATION TRAFFIC CONTROL SYSTEM

    African Journals Online (AJOL)

    user

    2017-01-01

    Jan 1, 2017 ... Software simulation was carried out using the Proteus virtual system modeling ... system which helps in track switching and level crossing gate traffic control is capable of improving reliability, speed, .... Lane Switching Network.

  17. Risk Mitigation for Highway and Railway Bridges

    Science.gov (United States)

    2009-02-01

    Performance of the transportation network strongly depends on the performance of bridges. Bridges constitute a vital part of the transportation infrastructure system and they are vulnerable to extreme events such as natural disasters (i.e., hurricane...

  18. Research on configuration of railway self-equipped tanker based on minimum cost maximum flow model

    Science.gov (United States)

    Yang, Yuefang; Gan, Chunhui; Shen, Tingting

    2017-05-01

    In the study of the configuration of the tanker of chemical logistics park, the minimum cost maximum flow model is adopted. Firstly, the transport capacity of the park loading and unloading area and the transportation demand of the dangerous goods are taken as the constraint condition of the model; then the transport arc capacity, the transport arc flow and the transport arc edge weight are determined in the transportation network diagram; finally, the software calculations. The calculation results show that the configuration issue of the tankers can be effectively solved by the minimum cost maximum flow model, which has theoretical and practical application value for tanker management of railway transportation of dangerous goods in the chemical logistics park.

  19. High speed in Portugal - metamorphosis from planning construction measures to a national railway concept; Hochgeschwindigkeit in Portugal - von der Bauplanung zu einem nationalen Eisenbahnkonzept

    Energy Technology Data Exchange (ETDEWEB)

    Stohler, Werner [Beratungfirma SMA und Partner AG, Zuerich (Switzerland)

    2010-03-15

    Portugal is planning the construction of two high-speed railway lines (using the UIC gauge of 1435 mm) between Lisbon and Madrid and between Lisbon and Porto. Integration with the country's existing Iberian-gauge network will be achieved in some places by laying three-rail tracks and in other places by running trains with adjustable wheel gauges. The adaptations to the legacy network triggered by the plants for the high-speed lines include, inter alia, a rearrangement of the networks of the regional-express services in and around Lisbon and Porto. (orig.)

  20. 77 FR 25229 - Adams-Warnock Railway, Inc.-Lease and Operation Exemption-Norfolk Southern Railway Company

    Science.gov (United States)

    2012-04-27

    ....31 to lease from Norfolk Southern Railway Company (NSR), and to operate, a line of railroad referred to as the Brampton Lead, beginning just beyond the northernmost turnout switch at NSR milepost FL 5.5... revoke the exemption under 49 U.S.C. 10502(d) may be filed at any time. The filing of a petition to...