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Letteratura scientifica selezionata sul tema "Railway problems"

Autore: Grafiati

Pubblicato: 12 ottobre 2024

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Articoli di riviste sul tema "Railway problems"

Zong, Ruixue. "Power Quality Problems of the Electrified Railway and Its Control Methods". Journal of Physics: Conference Series 2496, n. 1 (1 maggio 2023): 012017. http://dx.doi.org/10.1088/1742-6596/2496/1/012017.

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Abstract In developing the railway industry, the electrified railway plays a significant role in improving the national economy. However, the electric railway power supply system will be affected by power quality problems such as negative sequence, harmonic, and voltage fluctuation in actual operation, which will affect the operation efficiency of the electric railway power supply system. Therefore, it is meaningful to take economic and effectual governance measures against the power quality problems of electrified railways and reduce various indicators to the range allowed by a national standard. This paper summarizes and sorts out the main problems and their causes of current electrified railway power quality and several existing mainstream power quality governance schemes. It analyzes their advantages and disadvantages and finally looks forward to the directions that can be optimized and improved in the future study of electrified railway power quality problems in combination with social reality. It has a specific guiding effect on future research on electrified railway power quality.

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Wang, Junzhe. "Analysis of the Principle and Applications of Aerodynamics of High-speed Railway". Highlights in Science, Engineering and Technology 72 (15 dicembre 2023): 530–35. http://dx.doi.org/10.54097/ymwbxx75.

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With the advancement of science and technology, the railway has become an important breakthrough. Railroads can transport goods and carry people. Aerodynamics has a huge connection to the study of the high-speed railways. On this basis, the subject of this paper is the principle and application analysis of high-speed railway aerodynamics. To be specific, this study introduces the formulas and principles related to aerodynamics, and how some formulae are used in high-speed railways. The research searches for literature related to railway and aerodynamics and finds the current development status of high-speed railway. The paper explains how aerodynamics affect high-speed rail, the way to transform high-speed railways with aerodynamic knowledge. Contemporarily, there are many methods to carry out the simulation and tunnel experiments. This study also introduces some special experiments to solve special problems about high-speed railway. According to the analysis, there are still many aerodynamic problems that people need to solve, and there is room for improvement in high-speed railways.

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Michniak, Daniel. "Role of Railway Transport in Tourism: Selected Problems and Examples in Slovakia". Quaestiones Geographicae 35, n. 4 (1 dicembre 2016): 107–20. http://dx.doi.org/10.1515/quageo-2016-0039.

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AbstractTransport is a very important part of activities in the tourism sector. In addition to the transport of tourists to and within a destination, transport itself can be a tourist attraction. The aim of this paper is to analyse selected problems of railways in Slovakia (a decrease in the importance of railways for passenger transport in Slovakia in the past 20 years, discontinued passenger transport on certain railway tracks and the modernisation of other tracks, and zero-fare public rail transport services for certain categories of passengers), and to present good examples of the use of narrow-gauge railways for the purposes of tourism (the Tatra Electric Railways and the Kysuce-Orava Forest Railway).

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Moistsrapishvili, Manana, Nugzar Rurua e Angi Gurgenidze. "Approaches to Solving the Problems of Operation of Low Load Tension Railway Lines (LLRL) and Concepts of Key Strategies". Works of Georgian Technical University, n. 2(524) (6 giugno 2022): 133–39. http://dx.doi.org/10.36073/1512-0996-2022-2-133-139.

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It is known that the effective functioning of the railways depends on their load-bearing capacity, and therefore, special attention is paid to the pre-feasibility study and the payback period of the capital investments invested in the works during the capital investments of the railways. Because the operation of railway lines is associated with significant costs, its existence within the allowable limits of its size requires periodic evaluation and planning and implementation of engineering measures. The essence of the problem created by the operation of lowload railways of the world and Georgian railways are discussed. The main reasons for the deterioration of the operating data of these railways are reviewed. Low load railway lines are separated throughout the Georgian Railway and their total length and percentage composition in the overall railway network of the country are determined. The article outlines the main trends in the operation of low-load railways identified as a result of the analysis of foreign experience and presents four strategies based on this trends. Not yet established state approach to the use of LLRL infrastructure in Georgia can be based on the above mentioned stratages. It is noted that each of the proposed strategies has different efficiencies and selection conditions, so it should be considered according to the problems of each low-load rail section with innovative and / or traditional approaches to develop adaptive mechanisms for the operation of low-activity railway lines.

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Razumova, O. Yu, e I. M. Basyrov. "Problems of recovery of lost profits in the organization of freight rail transportation". Transport Technician: Education and Practice 4, n. 2 (23 giugno 2023): 174–83. http://dx.doi.org/10.46684/2687-1033.2023.2.174-183.

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The interests of clients of the railway industry and Russian Railways in matters of recovery and compensation for “lost profits” and “lost opportunities” are not considered and regulated in laws and by-laws regarding railway transportation. Claim work is based on compensation for real damage both from users of railway transport services and from the Russian Railways holding.An algorithm for the formation, submission and resolution of claims in the provision of rail transportation services is considered. The functionality of the personal account for the clients of JSC “Russian Railways” of the project “Electronic Claimant” was analyzed. The importance of developing a basic formula that takes into account the factors affecting the amount of lost profits is indicated. The existing scheme for conducting recourse work to recover losses of Russian Railways JSC is given and a scheme for conducting claim work to compensate for lost profits of Russian Railways JSC on the basis of a unified automated system of act and claim work is presented. It is proposed as a basis for further elaboration of this issue, a mechanism for rebilling in the event of final losses from a failed transportation for clients of the Russian Railways holding. The expediency of applying a possible replacement transaction when the company finds another counterparty is also considered. The application of these measures will make it possible to create equal competitive conditions in the market for all customers and the Russian Railways holding.

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CHARKINA, T., e A. HRYHORENKO. "TRANSFORMATION OF PASSENGER TRANSPORT MANAGEMENT STRUCTURE IN RAILWAY TRANSPORT: WORLD EXPERIENCE AND ITS ADAPTATION TO MODERN CONDITIONS IN UKRAINE". REVIEW OF TRANSPORT ECONOMICS AND MANAGEMENT, n. 10(26) (31 marzo 2024): 150–62. http://dx.doi.org/10.15802/rtem2023/300532.

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Objective. To enhance the competitiveness of railway passenger transportation in Ukraine, it is necessary to explore the experience of structural transformations in passenger enterprises of foreign railways, analyze the current state of the domestic railway passenger transportation management system, and propose an effective organizational structure for the passenger complex of Ukrainian Railways PJSC in modern conditions. Methodology. To achieve the stated objective, methods of analogy, modeling, comparative, and retrospective analysis were applied. Results. The world experience of interaction between organizational units of railway passenger complexes has been considered. An analysis has been conducted, and problems in the interaction of departments in the existing railway passenger transportation management system have been identified. A management structure for the passenger complex of Ukrainian Railways PJSC has been proposed, which will help optimize its operation and contribute to the increased efficiency of railway passenger transportation in Ukraine. Scientific novelty. The stages of transformation of the management structure of the passenger complex after the formation of Ukrainian Railways PJSC have been generalized. The passenger complex is considered as a single system: based on the visualization of the distribution of work with trains of different categories, problems of delineation of responsibility zones between the departments of the passenger complex have been identified. A model of an improved organizational structure for managing the passenger complex of railway transport has been developed in accordance with modern conditions. Practical significance. The proposed measures can be applied by Ukrainian Railways PJSC to improve the organizational structure of the passenger complex in the process of transitioning to a vertically integrated management model.

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Oh, Kyuetaek, Mintaek Yoo, Nayoung Jin, Jisu Ko, Jeonguk Seo, Hyojin Joo e Minsam Ko. "A Review of Deep Learning Applications for Railway Safety". Applied Sciences 12, n. 20 (19 ottobre 2022): 10572. http://dx.doi.org/10.3390/app122010572.

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Railways speedily transport many people and goods nationwide, so railway accidents can pose immense damage. However, the infrastructure of railways is so complex that its maintenance is challenging and expensive. Therefore, using artificial intelligence for railway safety has attracted many researchers. This paper examines artificial intelligence applications for railway safety, mainly focusing on deep learning approaches. This paper first introduces deep learning methods widely used for railway safety. Then, we investigated and classified earlier studies into four representative application areas: (1) railway infrastructure (catenary, surface, components, and geometry), (2) train body and bogie (door, wheel, suspension, bearing, etc.), (3) operation (railway detection, railroad trespassing, wind risk, train running safety, etc.), and (4) station (air quality control, accident prevention, etc.). We present fundamental problems and popular approaches for each application area. Finally, based on the literature reviews, we discuss the opportunities and challenges of artificial intelligence for railway safety.

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VERNYHORA, R., R. KOROBIOVA e O. PROKOPA. "PROBLEMS OF FREIGHT CAR FLOWS DISTRIBUTION ON RAILWAY NETWORKS". Transport systems and transportation technologies, n. 28 (26 settembre 2024): 34–42. http://dx.doi.org/10.15802/tstt2024/312028.

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Purpose. The purpose of the article is a critical analysis of the existing methods of freight car flows distribution on the railway network and the determination of the directions of these methods adaptation to the operating conditions of the Ukrainian railway transport. Methodology. The research was carried out on the basis of the processing of literary sources in the scientometric databases Scopus and Google Scholar. Results. The distribution of car flows on the railway network is one of the stages of developing a plan for the trains formation. The methods of solving this problem, which are currently used in the practical work of railway transport, were developed during the time of the planned state economy. They are based on the solution of a single-criterion optimization problem aimed at finding such a distribution of car flows on the network that minimizes the cost of transportation for the railway. Reforming the railway transport market with the aim of introducing competition requires the complication of methods of solving the problem of distribution of car flows to take into account the conflicting goals of independent participants in the transport process. The conducted studies showed that the main method of modeling the structure of the railway transport network and the volumes of car flows in it is the theory of graphs; determination of the carrying capacity of elements of the railway network is carried out by the methods of the theory of railway operation, simulation modeling and correlation analysis; determination of the optimal distribution of bandwidth is carried out by comparing competing options, as well as by linear and non-linear programming methods, adaptive control methods using neural networks; the behavior of participants in the transportation process during the allocation of bandwidth is investigated by game theory methods. It has been established that in modern conditions, the task of determining the criterion of equal access to congested sections on the branched railway network and the task of distributing car flows on the network in conditions of fluctuating car flows during transportation by regular trains and trains to order require additional research. Originality. The scientific novelty of the work consists in the critical analysis and generalization of modern methods used to solve the problem of distribution freight car flows distribution on railway networks. Practical value. The practical significance of the results lies in determining the inconsistency of the methods that are practically used on the railways of Ukraine for the distribution of car flows, with the modern conditions of operation of railway transport. Scientific methods have been established that allow to improve approaches to solving the problem of rational distribution of car flows, taking into account the interests of various participants in the transportation process.

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Ekimci, Betül, Feray Ergincan e Mehmet İnceoğlu. "Railroad Buildings of Eskişehir: Challenges and Opportunities for Industrial Heritage". Heritage 2, n. 1 (30 gennaio 2019): 435–51. http://dx.doi.org/10.3390/heritage2010030.

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While railways are considered as a sign of development for countries, the railway structures are part of the industrial heritage of cities and comprise some of the most important urban public places. In Turkey, the Eskişehir railway buildings, constructed between 1886 and 1894, are at the west of the main railroad between the Enveriye and Eskişehir stations. They are also public places having strong resonance in the collective memory. Because of the fast development in technology, they face the threat of losing their function. Conservation of former industrial structures requires, first and foremost, identifying and documenting the distinctive features that makes them cultural heritage sites. It is a shared responsibility between public institutions and sectors to identify and protect the distinguishing features of industrial heritage sites. With this awareness, at the Anadolu University Architecture Department, integrated student work focused on the Railroad Roundhouse—built in 1896—and Staff Housing Quarters—built in the early 20th century—which are part of this district and embody a series of urban problems, was carried out over four academic semesters. This study focuses on historic railway buildings in the Eskişehir railway district that is known for its urban problems. An exhibition combining these student works was opened at the Railcar Repair Facility on 16 November 2017. This exhibition showcased the student involvement in history of Eskişehir and increased public awareness of cultural heritage.

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Mishchenko, M. I. "Issues of vertical dividing the railways in the european sector". Science and Transport Progress, n. 40 (25 aprile 2012): 289–95. http://dx.doi.org/10.15802/stp2012/7177.

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Activity of a railway transportation of the countries of the European sector in its vertical division is investigated and the basic problems which have led to infringement of process of harmonisation of a current condition of railways with the current legislation in sphere of a railway transportation of EU are defined.

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Più fonti

Tesi sul tema "Railway problems"

Grange, Camille. "Design and application of quantum algorithms for railway optimisation problems". Electronic Thesis or Diss., Université de Montpellier (2022-....), 2024. http://www.theses.fr/2024UMONS009.

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Cette thèse est dédiée à la conception et à l’application d’algorithmes quantiques pour la résolution de problèmes d’optimisation combinatoire ferroviaires. Aujourd’hui, les problèmes d’optimisation auxquels fait face la SNCF sont complexes, empêchant souvent une résolution à l’optimalité via des méthodes classiques en un temps raisonnable. L’informatique quantique est pressentie pour améliorer la qualité des solutions et diminuer le temps de calcul pour certains de ces problèmes. Actuellement, les algorithmes quantiques pour l’optimisation se divisent en deux classes : les algorithmes exacts et les heuristiques. Les premiers présentent un avantage théorique pour plusieurs problèmes, mais ne sont pas implémentables sur les machines actuelles car trop gourmands en ressources. Les seconds sont implémentables dès aujourd’hui, au moins sur de petites instances, ouvrant la porte aux premières applications, bien qu’ils ne présentent pas encore de garanties de performances ni d'avantage quantique. Dans cette thèse, nous analysons et proposons des algorithmes qui appartiennent à chacune de ces deux classes.D’une part, nous étudions une classe d’heuristiques appelée Algorithmes Variationnels Quantiques. Il s’agit d’algorithmes hybrides quantique-classique, qui alternent entre l’exécution d’un circuit quantique paramétré et l’optimisation classique des paramètres. Ils permettent de résoudre des problèmes non contraints à variables binaires, et nous proposons une méthode générale pour reformuler des problèmes contraints à variables entières sous cette forme. Nous présentons certaines propriétés des Algorithmes Variationnels Quantiques, nécessaires pour envisager des preuves théoriques de garanties de performances. En particulier, nous étudions QAOA (Quantum Approximate Optimization Algorithm) en l'analysant à la lumière des précédentes propriétés et en donnant une décomposition universelle de son circuit quantique pour des problèmes dont la fonction objectif est polynomiale. Avec cet algorithme, nous résolvons un problème de conception de plan de transport de la SNCF. Ce problème a pour but de trouver un plan de transport qui correspond au meilleur compromis économique entre les bénéfices générés par la vente de billets aux voyageurs et les coûts d'exploitation, tout en respectant la disponibilité du réseau ferroviaire. Pour résoudre ce problème avec QAOA, nous proposons deux simplifications correspondant à différentes adaptations du problème métier initial.D’autre part, nous élaborons des algorithmes quantiques-classiques exacts pour deux grandes familles de problèmes combinatoires. La première famille concerne les problèmes d’ordonnancement. L’algorithme proposé s’applique à une large classe de problèmes d’ordonnancement à une machine, NP-difficiles, qui satisfont une propriété de programmation dynamique particulière (Dynamic Programming Across the Subsets). L’algorithme, reprenant l’idée de Ambainis et al. (2019), allie la programmation dynamique classique et l’algorithme quantique de recherche du minimum dans une table (basé sur l’algorithme de Grover). Il permet de réduire la complexité en temps pire-cas, parfois au détriment de l’introduction d’un terme pseudo-polynomial. Nous étendons cet algorithme au problème du flowshop à trois machines, pour lequel une accélération est aussi obtenue. La deuxième famille relève des problèmes d’optimisation robuste où l’ensemble d’incertitude est un polytope. Nous proposons un algorithme qui, partant de l’algorithme classique traitant de ces problèmes, remplace certaines opérations par des routines quantiques afin d’obtenir une accélération. Précisément, nous étudions l'utilisation des deux routines quantiques suivantes : la recherche du minimum dans une table et la résolution d’un système linéaire
This thesis is dedicated to the conception and application of quantum algorithms for railway combinatorial optimization problems. Today, the optimization problems that SNCF faces are complex, often prohibiting finding the optimal solution for industrial instances with classical methods within a reasonable amount of time. Quantum computing is expected to improve the quality of solutions and reduce the computation time for some of these problems. Quantum algorithms for optimization are divided into two classes: exact algorithms and heuristics. The former demonstrate theoretical advantages for several problems but cannot be implemented on current quantum machines because they require too high-quality quantum resources. On the contrary, the latter can be implemented, at least for small instances, but there are no performance guarantees or proven quantum advantages yet. In this thesis, we analyze and propose algorithms that belong to each of these two classes.On the one hand, we study the Variational Quantum Algorithms, which belong to the class of heuristics. These are hybrid quantum-classical algorithms that alternate between a parametrized quantum circuit and a classical optimizer. They allow solving unconstrained problems with binary variables, and we propose a general method to reformulate constrained integer problems into such problems. We highlight some properties of Variational Quantum Algorithms necessary for potential theoretical guarantees. In particular, we study QAOA (Quantum Approximate Optimization Algorithm) in light of the previous properties, and we provide a universal decomposition of the quantum circuit for problems whose objective function is polynomial. We solve with this algorithm a railway timetabling problem of SNCF. It consists of finding the transportation plan maximizing the operating profit according to the customers' demand taking into account the availability and cost of both the network and the rolling stock. To solve it with QAOA, we propose two simplifications with different adaptations of the original problem.On the other hand, we design exact quantum-classical algorithms for two broad families of combinatorial problems. The first family relates to scheduling problems. We propose an algorithm that tackles a large class of NP-hard single-machine scheduling problems, which satisfy a specific dynamic programming property (Dynamic Programming Across the Subsets). Our algorithm, based on the seminal idea of Ambainis et al. (2019), combines classical dynamic programming and quantum search of the minimum in a table (generalization of Grover Search). It reduces the worst-case time complexity, sometimes at the cost of an additional pseudopolynomial factor. We extend this algorithm to the 3-machine flowshop problem, also leading to a reduction of the complexity. The second family concerns robust optimization problems where the uncertainty set is a polytope. We present an algorithm that, relying on the classical method that deals with these problems, replaces some computations with quantum subroutines to achieve a speedup. Specifically, we study the two following quantum subroutines: the search of the minimum in a table and the resolution of a linear system

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Cacchiani, Valentina <1977&gt. "Models and algorithms for combinatorial optimization problems arising in railway applications". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/344/1/Tesi_Cacchiani.pdf.

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Beygang, Katharina [Verfasser]. "On the Solution of Some Railway Freight Car Optimization Problems / Katharina Beygang". München : Verlag Dr. Hut, 2011. http://d-nb.info/101735345X/34.

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Eaton, Jayne. "Ant colony optimisation for dynamic and dynamic multi-objective railway rescheduling problems". Thesis, De Montfort University, 2017. http://hdl.handle.net/2086/14950.

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Recovering the timetable after a delay is essential to the smooth and efficient operation of the railways for both passengers and railway operators. Most current railway rescheduling research concentrates on static problems where all delays are known about in advance. However, due to the unpredictable nature of the railway system, it is possible that further unforeseen incidents could occur while the trains are running to the new rescheduled timetable. This will change the problem, making it a dynamic problem that changes over time. The aim of this work is to investigate the application of ant colony optimisation (ACO) to dynamic and dynamic multiobjective railway rescheduling problems. ACO is a promising approach for dynamic combinatorial optimisation problems as its inbuilt mechanisms allow it to adapt to the new environment while retaining potentially useful information from the previous environment. In addition, ACO is able to handle multi-objective problems by the addition of multiple colonies and/or multiple pheromone and heuristic matrices. The contributions of this work are the development of a junction simulator to model unique dynamic and multi-objective railway rescheduling problems and an investigation into the application of ACO algorithms to solve those problems. A further contribution is the development of a unique two-colony ACO framework to solve the separate problems of platform reallocation and train resequencing at a UK railway station in dynamic delay scenarios. Results showed that ACO can be e ectively applied to the rescheduling of trains in both dynamic and dynamic multi-objective rescheduling problems. In the dynamic junction rescheduling problem ACO outperformed First Come First Served (FCFS), while in the dynamic multi-objective rescheduling problem ACO outperformed FCFS and Non-dominated Sorting Genetic Algorithm II (NSGA-II), a stateof- the-art multi-objective algorithm. When considering platform reallocation and rescheduling in dynamic environments, ACO outperformed Variable Neighbourhood Search (VNS), Tabu Search (TS) and running with no rescheduling algorithm. These results suggest that ACO shows promise for the rescheduling of trains in both dynamic and dynamic multi-objective environments.

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Aguiar, Eduardo Pestana de. "Fuzzy logic system applied to classification problems in railways". Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/3627.

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This thesis presents new fuzzy models applied to classification problems. With this regards, we introduce the use of set-membership concept, derived from the adaptive filter theory, into the training procedure of type-1 and singleton/non-singleton fuzzy logic systems, in order to reduce computational complexity and to increase convergence speed. Also, we present different criteria for using together with set-membership. Furthermore, we discuss the usefulness of delta rule delta, local Lipschitz estimation, variable step size and variable step size adaptive algorithms to yield additional improvement in terms of computational complexity reduction and convergence speed. Another important contribution of this thesis is to address the height type-reduction and to propose a modified version of interval singleton type-2 fuzzy logic system, so−called upper and lower singleton type-2 fuzzy logic system. The obtained results are compared with other models reported in the literature, demonstrating the effectiveness of the proposed classifiers and revealing that the proposals are able to properly handle with uncertainties associated with the measurements and with the data that are used to tune the parameters of the model. Based on data set provided by a Brazilian railway company, the models outlined above are applied in the classification of three possible faults and the normal condition of the switch machine, which is an equipment used for handling railroad switches. Finally, this thesis discusses the use of set-membership concept into the training procedure of an interval and singleton type-2 fuzzy logic system and of an upper and lower singleton type-2 fuzzy logic system, aiming to reduce computational complexity and to increase the convergence speed and the classification ratio. Also, we discuss the adoption of different criteria together with set-membership based-techniques. The performance is based on the data set composed of images provided by the same Brazilian railway company, which covers the four possible rail head defects and the normal condition of the rail head. The reported results show that the proposed models result in improved convergence speed, slightly higher classification ratio and remarkable computation complexity reduction when we limit the number of epochs for training, which may be required due to real time constraint or low computational resource availability.

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Hoffmann, Kirsten [Verfasser], Udo [Gutachter] Buscher e Rainer [Gutachter] Lasch. "Railway crew scheduling problems with attendance rates / Kirsten Hoffmann ; Gutachter: Udo Buscher, Rainer Lasch". Dresden : Technische Universität Dresden, 2020. http://d-nb.info/1227202644/34.

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Blomqvist, Mattias, e Michael Blomqvist. "Problematik kring spårväxlar : Framtida åtgärdsförslag". Thesis, KTH, Byggteknik och design, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127658.

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Sveriges järnvägsnät är gammalt och utsätts för en allt högre belastning varje år i takt med att trafiken på spåren ökar. Detta medför att slitaget på järnvägarna ökar och en väldigt känslig del är spårväxlar. Då ca 20 % av alla fel beror på problem med spårväxlar läggs fokus i rapporten på att utreda denna problematik. Syftet med arbetet är att kartlägga vilka spårväxelfel som uppstår och orsaken till dessa, samt att komma med åtgärdsförslag för att minska problemen med spårväxlar som leder till förseningar och stopp i trafiken. Rapportens inledande del består av ett teoriavsnitt som beskriver hur en växel är uppbyggd och hur den fungerar. Tre bandelar i Sverige har studerats, en i norr, en i söder och en i Stockholm. Studierna har baserats på samtliga felrapporter tillhörande spårväxlar i Ofelia som rapporterats in mellan åren 2009 och 2012. Statistiken ger generella svar på vilka problem som uppstår i spårväxlar och i vilken omfattning de förekommer. Den visar också tydliga skillnader på år med svåra vintrar respektive år med mindre svåra vintrar. Resultatet av studierna visar att det är felkategorierna ”ingen känd orsak”, ”snö eller is” och ”materialutmattning/åldring” som förekommer mest frekvent. I rapportens avslutande del redovisas de mest frekventa kategorierna djupare. Idéer och förslag presenteras på eventuella lösningar. Förslagen är framför allt framtagna för att hantera problem orsakade av snö och is.
The Swedish railway network is old and it is subjected to an increasing load each year as the traffic on the railway tracks increases. This increases the wear on the tracks and a very sensitive part that constantly suffers problems is the railway switch. As the switches account for 20% of all the errors on the railway this report is focused on the problems related to switches. The aim of this work is to identify the problems with switches and what causes them. The aim is also to come up with proposals for measures to reduce the problems of switches that lead to delays and traffic jams. The first part of the report consists of a theory section that describes how a switch is constructed and how it works. Three railway distances in Sweden have been studied, one in the north parts of the country, one in the south and one in the city of Stockholm. These studies are based on all errors associated with switches that were reported in the Swedish error report system Ofelia during the years 2009 and 2012. These statistics provide general information about the problems that arise in switches in Swedish railway and to what extent they arise. The statistics also show a clear difference in the number of error reports during years with severe winter weather compared to less harsh winters. The report shows that errors reported as "no known cause", "snow and ice" and "material fatigue / aging" occurs most frequently. In the concluding section of the report the most frequent categories are presented in further detail. Based on this research, ideas and suggestions are presented. These proposals are mainly designed to handle problems caused by snow and ice.

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Tambellini, Irene <1993&gt. "Chongqing-Xinjiang-Europe International Railway: problems and challenges of the first direct rail connection between China and Europe". Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/14924.

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Through this master’s degree thesis, I will try to investigate the development, the characteristics and the weak points of the Chongqing-Xinjiang-Europe International Railway line (also known as Yuxinou). It was created in 2011 and it links the municipality of Chongqing to the city of Duisburg in Germany. The municipality as well as the Yuxinou railway line are increasingly important for the Chinese propaganda, which has identified Chongqing as an important economic hub for the whole nation and the Yuxinou railway as the forerunner of the rail trade’s development between China and Europe. But how much is this railway contributing to the development of Sino-European trade relations? Can rail transport really replace the maritime transport or at least be a viable alternative? The first chapter focuses on the birth and development of Chongqing since 1997, when it became a municipality, until today. Its role in the Western Development Strategy and in the Belt and Road Initiative will be analyzed. The second chapter gives an overview of the rail and maritime connections that China has developed with the European countries and it makes a description of the two types of transport, highlighting their advantages and disadvantages, critical points and strengths. Finally, the third chapter focuses on the Yuxinou railway, it describes the context in which the railway was born and the complexities and difficulties that still characterize it today.

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Perrin, Guillaume. "Random fields and associated statistical inverse problems for uncertainty quantification : application to railway track geometries for high-speed trains dynamical responses and risk assessment". Phd thesis, Université Paris-Est, 2013. http://pastel.archives-ouvertes.fr/pastel-01001045.

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Les nouvelles attentes vis-à-vis des nouveaux trains à grande vitesse sont nombreuses: on les voudrait plus rapides, plus confortables, plus stables, tout en étant moins consommateur d'énergie, moins agressif vis-à-vis des voies, moins bruyants... Afin d'optimiser la conception de ces trains du futur, il est alors nécessaire de pouvoir se baser sur une connaissance précise de l'ensemble des conditions de circulations qu'ils sont susceptibles de rencontrer au cours de leur cycle de vie. Afin de relever ces défis, la simulation a un très grand rôle à jouer. Pour que la simulation puisse être utilisée dans des perspectives de conception, de certification et d'optimisation de la maintenance, elle doit alors être tout à fait représentative de l'ensemble des comportements physiques mis en jeu. Le modèle du train, du contact entre les roues et le rail, doivent ainsi être validés avec attention, et les simulations doivent être lancées sur des ensembles d'excitations qui sont réalistes et représentatifs de ces défauts de géométrie. En ce qui concerne la dynamique, la géométrie de la voie, et plus particulièrement les défauts de géométrie, représentent une des principales sources d'excitation du train, qui est un système mécanique fortement non linéaire. A partir de mesures de la géométrie d'un réseau ferroviaire, un paramétrage complet de la géométrie de la voie et de sa variabilité semblent alors nécessaires, afin d'analyser au mieux le lien entre la réponse dynamique du train et les propriétés physiques et statistiques de la géométrie de la voie. Dans ce contexte, une approche pertinente pour modéliser cette géométrie de la voie, est de la considérer comme un champ aléatoire multivarié, dont les propriétés sont a priori inconnues. En raison des interactions spécifiques entre le train et la voie, il s'avère que ce champ aléatoire n'est ni Gaussien ni stationnaire. Ce travail de thèse s'est alors particulièrement concentré sur le développement de méthodes numériques permettant l'identification en inverse, à partir de mesures expérimentales, de champs aléatoires non Gaussiens et non stationnaires. Le comportement du train étant très non linéaire, ainsi que très sensible vis-à-vis de la géométrie de la voie, la caractérisation du champ aléatoire correspondant aux défauts de géométrie doit être extrêmement fine, tant du point de vue fréquentiel que statistique. La dimension des espaces statistiques considérés est alors très importante. De ce fait, une attention toute particulière a été portée dans ces travaux aux méthodes de réduction statistique, ainsi qu'aux méthodes pouvant être généralisées à la très grande dimension. Une fois la variabilité de la géométrie de la voie caractérisée à partir de données expérimentales, elle doit ensuite être propagée au sein du modèle numérique ferroviaire. A cette fin, les propriétés mécaniques d'un modèle numérique de train à grande vitesse ont été identifiées à partir de mesures expérimentales. La réponse dynamique stochastique de ce train, soumis à un très grand nombre de conditions de circulation réalistes et représentatives générées à partir du modèle stochastique de la voie ferrée, a été ainsi évaluée. Enfin, afin d'illustrer les possibilités apportées par un tel couplage entre la variabilité de la géométrie de la voie et la réponse dynamique du train, ce travail de thèse aborde trois applications

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Libri sul tema "Railway problems"

Cevelev, Aleksandr. Strategic development of railway transport logistics. ru: INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1194747.

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The monograph is devoted to the methodology of material and technical support of railway transport. According to the types of activities, the nature of the material and technical resources used, technologies, means and management systems, Russian railways belong to the category of high-tech industries that must have high quality and technical level, reliability and technological efficiency in operation. For this reason, the logistics system itself, both in structure and in the algorithm of the functions performed as a whole, needs a serious improvement in the quality of its work. The economic situation in Russia requires a revision of the principles and mechanisms of management based on the corporate model of supply chain management, focused on logistics knowledge. In the difficult economic conditions of the current decade, it is necessary to improve the quality of the supply organization of enterprises and structural divisions of railway transport, directly related to the implementation of the process approach, the advantage of which is a more detailed regulation of management actions and their mutual coordination. In order to increase the efficiency of its activities and develop the management system, Russian Railways is developing a lean production system aimed at further expanding the implementation of the principles of customer orientation, ideology and corporate culture. At the present time, the solution of many issues is impossible without a cybernetic approach to the formulation of problems of material and technical support and logistics analysis of information technologies, to the implementation of the developed algorithms and models of development strategies and concepts for improving the business processes of the production system. The management strategy, or the general plan for the implementation of activities for the management of material resources, is based on a fundamental assessment of the alignment and correlation of forces and factors operating in the economic and political field, taking into account the impact on the specific form of the management strategy. The materials will be useful to the heads and specialists of the directorates of the MTO, CDZs and can be used in the scientific research of bachelors, masters and postgraduates interested in the economics of railway transport and supply logistics.

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Railway Problems. Nabu Press, 2010.

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Ripley, William Zebina. Railway Problems. Arkose Press, 2015.

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Ripley, William Zebina. Railway Problems. Arkose Press, 2015.

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Ripley, William Zebina. Railway Problems. Franklin Classics, 2018.

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Railway problems. Gale, Making of Modern Law, 2011.

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Railway Problems. Franklin Classics, 2018.

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Hsu, Mongton Chih. Railway Problems in China. Creative Media Partners, LLC, 2022.

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Haines, Henry Stevens. Problems In Railway Regulations. Arkose Press, 2015.

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Ripley, William Z. Railway Problems, Vol. 1. Beard Books, 2000.

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Capitoli di libri sul tema "Railway problems"

Webster, P. J., X. Wang e G. Mills. "Problems with Railway Rails". In Measurement of Residual and Applied Stress Using Neutron Diffraction, 517–24. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2797-4_43.

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True, Hans. "Bifurcation Problems in Railway Vehicle Dynamics". In Bifurcation: Analysis, Algorithms, Applications, 319–33. Basel: Birkhäuser Basel, 1987. http://dx.doi.org/10.1007/978-3-0348-7241-6_33.

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Tormos, P., A. Lova, F. Barber, L. Ingolotti, M. Abril e M. A. Salido. "A Genetic Algorithm for Railway Scheduling Problems". In Metaheuristics for Scheduling in Industrial and Manufacturing Applications, 255–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-78985-7_10.

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Matsuo, K., e T. Aoki. "Wave problems in high-speed railway tunnels". In Shock Waves, 95–102. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77648-9_10.

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Bärmann, Andreas. "Strategic Infrastructure Planning in Railway Networks". In Solving Network Design Problems via Decomposition, Aggregation and Approximation, 15–47. Wiesbaden: Springer Fachmedien Wiesbaden, 2016. http://dx.doi.org/10.1007/978-3-658-13913-1_3.

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Schöne, Eric J., e Qamar Mahboob. "Application of Risk Analysis Methods for Railway Level Crossing Problems". In Handbook of RAMS in Railway Systems, 551–70. Boca Raton : Taylor & Francis, CRC Press, 2018.: CRC Press, 2018. http://dx.doi.org/10.1201/b21983-30.

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Jütte, Silke. "Solving Crew Scheduling Problems in the Railway Industry". In Large-Scale Crew Scheduling, 32–56. Wiesbaden: Springer Fachmedien Wiesbaden, 2012. http://dx.doi.org/10.1007/978-3-658-24360-9_3.

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Caprara, Alberto, Matteo Fischetti, Pier Luigi Guida, Paolo Toth e Daniele Vigo. "Crew Scheduling and Rostering Problems in Railway Applications". In Operations Research and Decision Aid Methodologies in Traffic and Transportation Management, 228–43. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-662-03514-6_10.

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Shubinsky, Igor Borisovich, e Alexei Mikhailovitch Zamyshlaev. "Problems of Managing Technical Assets in Railway Domain". In International Series in Operations Research & Management Science, 3–14. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90029-8_2.

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Charkina, Tetiana, Viacheslav Zadoia e Oksana Dmytriieva. "Marketing management at railway transport enterprises". In Innovative development of the road and transport complex: problems and prospects, 158–71. Kharkiv, Ukraine: PRIVAT COMPANY TECHNOLOGY CENTER, 2023. http://dx.doi.org/10.15587/978-617-7319-71-8.ch10.

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Atti di convegni sul tema "Railway problems"

Tormos, P., M. Abril, M. A. Salido, F. Barber, L. Ingolotti e A. Lova. "Distributed constraint satisfaction problems to model railway scheduling problems". In COMPRAIL 2006. Southampton, UK: WIT Press, 2006. http://dx.doi.org/10.2495/cr060291.

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Lou, Lixing, e Yilin Yin. "Problems and solutions of railway engineering quota". In EM). IEEE, 2009. http://dx.doi.org/10.1109/icieem.2009.5344608.

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Beijer Lundberg, Anders. "LCA Design Considerations for Cyclically Loaded Piles in Railway Infrastructure". In The 13th Baltic Sea Region Geotechnical Conference. Vilnius Gediminas Technical University, 2016. http://dx.doi.org/10.3846/13bsgc.2016.003.

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Future development of high-speed railways in Sweden will likely contain a large amount of piled structures, both bridges and piled embankments. Railway tracks used in high-speed railways are highly sensitive to settlements, in comparison to standard railway systems. The possible long-term settlement of the piles is therefore of large interest for the life- Cycle Analysis (LCA) of the railway system, since frequent repair of the track increases the Life Cycle Cost (LCC) of the system. This issue has not previously been the main concern in pile design, and therefore requires special attention as an internal part of the railway support system. The design considerations related to the cyclic axial loading of piles are here analyzed in brief, and typical soil conditions are discussed to illuminate possible problems of practical design for these types of piles and how it can be addressed in practical design. The concept of LCA and LCC for the long-term structural response of cyclically loaded piles is also considered.

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Tatarintsev, V. A., e A. K. Tolstosheev. "Risk assessment and reliability of railway rolling stock elements". In PROCEEDINGS INTERNATIONAL CONFERENCE “PROBLEMS OF APPLIED MECHANICS”. AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0047254.

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Samsonkin, Valerii, Oksana Yurchenko, Viktor Myronenko e Julia Bulgakova. "Crisis Prevention Methods Based on Operational Risk Management: Railway Transport Case Study". In International Scientific Applied Conference "Problems of Emergency Situations". Switzerland: Trans Tech Publications Ltd, 2023. http://dx.doi.org/10.4028/p-d9fq6q.

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The result of experimental studies of the statistical database of technical failures and failures in the signaling and communication division of railway is presented in the paper. The principles and directions of crisis emergency prevention are considered. The main problems in finding an effective way to control the process of keeping the alarm systems in the required technical condition are defined. It is proposed to apply the method of preventing crisis situations (on the example of railway transport) for each systematization parameter in the developed classifier.

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Neklyudova, Galina, e Elena Evtuh. "CALCULATED SIMULATION OF THE DYNAMICS OF A RAILWAY WHEEL WHEN ROLLING THROUGH A BUTT CLEARANCE". In PROBLEMS OF APPLIED MECHANICS. Bryansk State Technical University, 2020. http://dx.doi.org/10.30987/conferencearticle_5fd1ed04082cb9.21621131.

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The article is devoted to the description of the creation of a computer model of the movement of a railway freight car along the section of the track adjacent to the rail joint. The model takes into account the elastic characteristics and ballast subsidence in the joint zone. The results of computer simulation are further used to solve the contact problem in the wheel-rail system. The study varied a number of parameters affecting this process of wheel movement. For the operating speeds of the freight car, the range of values of the dynamic forces arising between the wheel and the rail during the passage of the joint is determined.

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Vakulenko, Sergey, Alexey Kolin e Nadezhda Evreenova. "Problems of Effective Operation of Low-intensity Railway Lines". In 2020 13th International Conference Management of large-scale system development (MLSD). IEEE, 2020. http://dx.doi.org/10.1109/mlsd49919.2020.9247641.

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Antipin, Dmitriy, Vladimir Vorobev, Denis Bondarenko e T. Vetoshko. "CLASSIFICATION OF FIXING METHODS FOR TRACTION ELECTRIC MOTORS AND SEARCH FOR NEW TECHNICAL SOLUTIONS". In PROBLEMS OF APPLIED MECHANICS. Bryansk State Technical University, 2020. http://dx.doi.org/10.30987/conferencearticle_5fd1ed033e0406.17340047.

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The problem of the possibility of creating a classification of methods for attaching traction electric motors of railway locomotives to the bogie frame is considered. As a result of the analysis, a classification has been proposed that makes it possible to systematize the design of traction motor suspensions for all known types of drives, as well as suspensions of axial gearboxes. use.

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Тришин, Никита Алексеевич. "REPROFILING OF OKTYABRSKAYA RAILWAY DIVISIONS AND ENCOUNTERED DIFFICULTIES TO THE END OF THE 2022 YEAR". In Научные инновации как фактор развития: сборник статей международной научной конференции (Архангельск, Декабрь 2022). Crossref, 2023. http://dx.doi.org/10.58351/221203.2022.76.48.003.

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Данная статья посвящена проблеме взаимодействия при реализации процессов планирования и производства работ между дистанциями сигнализации, централизации и блокировки, специализирующимися на эксплуатации устройств железнодорожной автоматики и телемеханики и дистанциями, специализирующимися на их ремонте. Автором проведен анализ нормативно-технических документов ОАО «РЖД» и сформулированы действия для устранения выявленных проблемных моментов. This article is devoted to the problem of interaction during plan and work processes between the divisions of signaling, centralization and blocking, specializing in the maintenance of railway automation and remote control devices, and the divisions specializing in their repair. The author analyzed the normative and technical documents of JSC «Russian Railways» and formulated actions to eliminate the identified problems.

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Dolgikh, G. A., e P. A. Hilchenko. "THE CURRENT STATE OF THE TRANSPORT SYSTEM OF THE CRIMEAN PENINSULA. FEATURES OF PASSENGER TRAFFIC ON THE PENINSULA". In Problems of transformation and regulation of regional socio-economic systems. Petersburg State University of Economics, 2023. http://dx.doi.org/10.52897/978-5-7310-6226-8-2023-51-25-37.

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In this article, the transport system of the Crimea will be considered from the point of view of the characteristics of various types of transport according to criteria such as efficiency, safety, time costs and consumer preferences. The article will consider the infrastructure of the peninsula for all types of vehicles, as well as the main features of the passenger traffic of the Crimean peninsula, the dynamics of changes in the number of passengers, as well as factors affecting the sharp increase in rail passengers in recent years. An analysis of passengers' preferences by types of railway cars will be carried out and a conclusion will be made about the need to plan updates in the infrastructure of Russian Railways.

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Rapporti di organizzazioni sul tema "Railway problems"

Chong, Alberto E., e César Calderón. Volume and Quality of Infrastructure and the Distribution of Income: An Empirical Investigation. Inter-American Development Bank, aprile 2001. http://dx.doi.org/10.18235/0011560.

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We provide evidence on the link between infrastructure development and the distribution of income for the period 1960-1995. To do this, we use several proxies such as roads, railways, telecommunications and energy measures. The approach is comprehensive as cross-country and panel methods are applied. In the latter case, we apply GMM dynamic panel methods in order to minimize for endogeneity problems. Both quantity of infrastructure and quality of infrastructure are negatively linked with income inequality. The quantitative link tends to be stronger in developing countries than the qualitative link. These findings hold when using different econometric methods and most infrastructure measures.

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