Search results for "RAILWAY"
showing 10 items of 76 documents
A topological phase transition between small-worlds and fractal scaling in urban railway transportation networks?
2009
Abstract Fractal and small-worlds scaling laws are applied to study the growth of urban railway transportation networks using total length and total population as observational parameters. In spite of the variety of populations and urban structures, the variation of the total length of the railway network with the total population of conurbations follows similar patterns for large and middle metropolis. Diachronous analysis of data for urban transportation networks suggests that there is second-order phase transition from small-worlds behaviour to fractal scaling during their early stages of development.
The Rail Quality Index as an Indicator of the “Global Comfort” in Optimizing Safety, Quality and Efficiency in Railway Rails
2012
AbstractThe proposed model uses the stochastic dynamic programming and in particular Markov decision processes applied to the Rail Quality Index (RQI - Italian Indice di Qualità del Binario, IQB).By performing the integrated analysis of the classes of variables which characterize the overall service quality (in terms of comfort and safety), the proposed mathematical approach allows to find the solutions to the decision-making process in function of the probability of deterioration of the state variables of the infrastructure over time and of the flow of available resources.
Characterization of rubberized asphalt for railway sub-ballast. Improvements in the mix-design, performance features and rational methodology of HMA_…
2018
(STR) can be incorporated into asphalt mixtures in two different methods, which are referred to as the wet-dry process. The blending of recycled rubber (CRM) with asphalt has been used for years, and several manufacturing processes have been developed in Europe as well as in the USA. The use of a bituminous sub-ballast layer has been pointed out as an exciting alternative to the granular sub-ballast design traditionally applied in most railroad tracks. Frequently, unbound granular materials are replaced by bituminous sub-ballast that provide additional benefits to the subgrade protection. Much research has been conducted on finding other alternative material to be used as a modifier in asph…
In the rail sector, France needs to do more to connect its regional networks to the European network
2023
In an article for "Le Monde" newspaper, the legal expert Martial Pernet notes that, despite the texts in force, which he urges to be applied, efforts must be made to achieve the unification of the European rail network.
Dopo l'obsolescenza. Progetti per i viadotti ferroviari dismessi
2013
This article focuses on the increasing number of abandoned railways converted into new parkways, briefly investigating them trough the prism of obsolescence. Over the past forty years, the features matching with the average lifetime of infrastructural buildings have became of growing relevance dealing with contemporary policies in restructuring our territories. In the beginning of 21th century, facing the new challenges of the post-carbon era, cities of developed society are riddled with technical ruins, testaments to their recent productive past. Since the entanglement of transport infrastructure, industry and architecture highly represents important segments of 20th century urban tissues,…
WPŁYW PANDEMII COVID-19 NA FUNKCJONOWANIE REGIONALNEGO TRANSPORTU KOLEJOWEGO OBSZARÓW PRZYGRANICZNYCH – NA PRZYKŁADZIE WOJEWÓDZTWA DOLNOŚLĄSKIEGO (PL…
2021
Systemy zbiorowego transportu publicznego są narażone na wiele zewnętrznych czynników wpływających na ich funkcjonowanie. Jednym z nich może być zagrożenie epidemiologiczne. W 2020 r. światowa pandemia COVID-19 miała istotny wpływ na światową gospodarkę oraz przewozy pasażerskie. Wprowadzone liczne ograniczenia wpłynęły na popyt (liczbę pasażerów) oraz podaż (oferta przewozowa) na rynku transportu. Do najczęstszych obostrzeń zaliczyć można: ograniczenie liczby połączeń, zmniejszenie limitu pasażerów w pojeździe, ograniczenie siatki połączeń komunikacyjnych. W analizie autorzy przeprowadzili badanie województwa dolnośląskiego oraz kraju libereckiego w kontekście zmian w funkcjonowaniu region…
La rete ferroviaria ad Alta Velocità in Corea del Sud [The High-Speed Rail network in South Korea]
2012
LA RETE FERROVIARIA AD ALTA VELOCITA’ IN COREA DEL SUD High speed rail in South Korea
Novel performance-based technique for predicting maintenance strategy of bitumen stabilised ballast
2018
Abstract Despite being the most used worldwide, railway ballasted tracks presents high maintenance cost related to ballast settlement and particle degradation. With the aim of reducing life cycle costs, bitumen stabilised ballast (BSB) has been recently proposed as a relatively cheap alternative maintenance solution to be applied to existing tracks. This study aims at assessing the potential advantages of this technology, defining a novel maintenance strategy of traditional ballasted track-beds. A protocol for the application of the BSB technology and its associated maintenance strategy is defined. To estimate minor and major maintenance operations of BSB scenario in comparison to tradition…
Spatial conflicts betweem modernizations of railway lines and natural values A case study of Poznań - Szczecin railway line
2017
One of the most intensive processes in the development of Polish transport infrastructure is currently modernizing main national railway lines. One of them is the railway line between Poznan and Szczecin. During the realization of such projects there occur conflicts in fulfilling different ecosystem functions by landscapes. On the basis of the theory of ecosystem services these conflicts should be solved, and potential projects – optimized. The study evaluates natural values of the areas adjacent to the railway line Poznań - Szczecin within a zone of 250 m, and also identifies areas with varying conflict degrees for the realization of the modernization project. The most important areas of h…
A MARKOVIAN MODEL AS A TOOL FOR OPTIMISATION OF MAINTENANCE INTERVENTIONS ON RAILWAYS LINES
2008
This paper is designed to develop a procedure which defines a planning criterion for railway superstructure maintenance by means of Markov decision processes. This methodology allows to formulate a specific policy which carries out the best configuration of budget allocation (min. Ф), and at the same time to guarantee the highest efficiency level in the railway superstructure. Thanks to the dynamic programming technique applied to decision processes, the report has examined the possibility of establishing the best management policy in order to maintain adequate safety levels of implementation and quality speed levels, in the presence of budget constraints, thus optimizing the available re…