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Infrastructure, territoires et projets : l'exemple de la ligne ferroviaire à grande vitesse Lyon-Turin-Milan / Infractructure, territories and projects : the case of the high-speed railway Lyon-Turin-MilanTrotta-Brambilla, Gabriella 06 December 2013 (has links)
La construction d'une grande infrastructure ferroviaire peut-elle devenir une occasion pour (re)structurer le territoire traversé ? Cette question est à la base de la réflexion menée dans ce travail. Plus précisément, la thèse défendue peut être ainsi formulée : une grande infrastructure (dans ce cas le projet et la construction de la ligne ferroviaire à grande vitesse entre Lyon, Turin et Milan), sous certaines conditions (analysées dans la thèse), peut représenter une occasion pour redonner une structure plus cohérente à un territoire par le biais de l'articulation interscalaire et interdisciplinaire des réflexions sur la planification et des actions de projet sur le territoire même. L'état des lieux autour de la thématique de la grande vitesse ferroviaire et de son possible contexte territorial met en avant les domaines principaux de la littérature scientifique qui se sont occupés de cet argument (économie, géographie, sciences sociales et humaines). Cette thèse essaye de croiser plusieurs disciplines, mais en abordant la question d'un point de vue différent, celui de la planification territoriale et urbaine, puisque les thématiques traitées par la géographie des transports (accessibilité, rugosité, vitesse, nodalité, reticularité, etc.) ne semblent pas expliquer suffisamment les interactions à différentes échelles entre infrastructure et territoire. En interrogeant plans et projets, ainsi que des « expérimentations projectuelles » élaborées dans une démarche de research by design, cette thèse analyse les points de convergence entre le domaine des transports ferroviaires et celui de la planification durable du territoire et de la ville. / Can the construction of a big railway infrastructure become the occasion for (re)structuring the territory passed through? This is the base question of the reflection developed in this manuscript. More precisely, the thesis that we propose may be reformulated as follows: the realization of a big infrastructure (in our case the design of the high-speed railway between Lyon, Turin and Milan) can be the occasion to give the interested territory a more coherent structure by approaching the territorial planning in an inter-scalar and inter-disciplinary way. The analysis of the state of the art of the subjects of the high speed railway and of its territorial context may evidence, from time to time, one or another of the scientific domains that dealt with this topic (economy, geography, social and human sciences, etc.). This thesis tries to intersect multiple disciplines, but approaching the matter from a different point of view: that of urban and territorial planning. Indeed, the themes treated by the transportation geography do not seem able to explain sufficiently well the interactions between infrastructure and territory at all the different scales. By analyzing plans and projects as well as some « design experiments » elaborated with a research-by-design approach, we try to discuss in this manuscript the points of convergence between the domain of the railway transports and that of the sustainable planning of the territory and of the city.
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Innovative noise protection solutions for Sweden's first high speed railwayUppenberg, Caroline, Jonsson, Emma January 2018 (has links)
This thesis investigates and design innovative concepts of noise protection solutions (NPS) for the Swedish high-speed railway (HSR) that is planned to be built between Stockholm and Gothenburg in the near future. The planned traffic will start in 2035. The concepts have been developed through a design process, starting with a research phase of existing solutions for the problem, theory about noise and absorbing materials. Following by an analysis of all researched data to narrow down the project and the interviews with the Swedish transport administration, this in order to pinpoint the requirements for the NPS. To get opinions from people who are exposed to low frequency noise, two questionnaires were conducted with a total of 80 respondents. Because of the difficulty to find the exact target group of people who are only exposed to the noise from high speed trains, the first questionnaire was open for all people who are exposed to low frequency noise (traffic noise). The second questionnaire was published at Trafikverket Facebook page, and because of their high number of followers, people who are exposed to train noise could easily be reached. From the answers and the analyzed data, a requirement specification for the NPS was created with all the requirements that the NPS needed to have according to Trafikverkets standards and from the questionnaire. These requirements were the prerequisite used in the synthesis phase. Different brainstorming methods were used to develop a large amount of ideas. A workshop with people from the society was held to keep the creativity alive. From the first synthesis phase, six ideas out of 160 ideas were chosen by a dot evaluation, and in order to narrow down the ideas even more, a matrix evaluation was used. The matrix was built from the requirement specification to verify which ideas fit most of the requirements for a new NPS. From this evaluation, two concepts were chosen to be developed further. After a validation from Trafikverket, the two concepts were further developed, this by an open brainstorming session. Via discussions and sketching, new ideas for the concepts arose. We found solutions for the problems that arose with each concept and made final decisions about the design and material. Three concepts were 3D visualized in the CAD program Rhinoceros. Final touches of the concepts were made in Keyshot. Throughout this thesis, three concepts for noise protections for the HSR have been developed and the research question “How can innovation be created by using a design process?” have been discussed and answered.
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Čínské železniční diplomacie jako nástroj posilování soft power / China's High-Speed Railway Diplomacy (HSRD) as a Tool for Improving Soft PowerXiu, Lanyu January 2021 (has links)
The following thesis conducted a case study to investigate the opinion of exper ts working on the Bombay-Ahmadabad HSR and Ankara-Istanbul HSR on how China uses HSRD and BRI to develop and utilize its soft power and whether that opinion ma tches the official Chinese point of view. The official Chinese view about BRI is that it seeks to deliver win-win outcomes, development, and improvement of lives for partici pating countries. In addition, it 'has no geopolitical motives, seeks no exclusionary bl ocs, and imposes no business deals on others … addresses people's desire for a better l ife … and shared benefits.' Ramo (2007)'s operationalization of the term global image was used to assess the respondents' opinions. The results showed that there is low dependability of the overa ll BRI among the respondents. A majority of the respondents (60%) claimed that BRI and HSRD are successful but were not impressed by the delivered value and quality o f BRI. 70% of the respondents believed that the Bombay-Ahmadabad HSR would ach ieve its objective and that it had a high level of technology. In terms of financial, socia l and political impact, the responses showed proportions of 40%, 37%, 44% respectiv ely gave a positive answer. Overall, it can be concluded that in terms of image the Bo mbay-Ahmadab gave...
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Machine Learning – Based Dynamic Response Prediction of High – Speed Railway BridgesXu, Jin January 2020 (has links)
Targeting heavier freights and transporting passengers with higher speeds became the strategic railway development during the past decades significantly increasing interests on railway networks. Among different components of a railway network, bridges constitute a major portion imposing considerable construction and maintenance costs. On the other hand, heavier axle loads and higher trains speeds may cause resonance occurrence on bridges; which consequently limits operational train speed and lines. Therefore, satisfaction of new expectations requires conducting a large number of dynamic assessments/analyses on bridges, especially on existing ones. Evidently, such assessments need detailed information, expert engineers and consuming considerable computational costs. In order to save the computational efforts and decreasing required amount of expertise in preliminary evaluation of dynamic responses, predictive models using artificial neural network (ANN) are proposed in this study. In this regard, a previously developed closed-form solution method (based on solving a series of moving force) was adopted to calculate the dynamic responses (maximum deck deflection and maximum vertical deck acceleration) of randomly generated bridges. Basic variables in generation of random bridges were extracted both from literature and geometrical properties of existing bridges in Sweden. Different ANN architectures including number of inputs and neurons were considered to train the most accurate and computationally cost-effective mode. Then, the most efficient model was selected by comparing their performance using absolute error (ERR), Root Mean Square Error (RMSE) and coefficient of determination (R2). The obtained results revealed that the ANN model can acceptably predict the dynamic responses. The proposed model presents Err of about 11.1% and 9.9% for prediction of maximum acceleration and maximum deflection, respectively. Furthermore, its R2 for maximum acceleration and maximum deflection predictions equal to 0.982 and 0.998, respectively. And its RMSE is 0.309 and 1.51E-04 for predicting the maximum acceleration and maximum deflection prediction, respectively. Finally, sensitivity analyses were conducted to evaluate the importance of each input variable on the outcomes. It was noted that the span length of the bridge and speed of the train are the most influential parameters.
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Numerical modelling of high-speed railway transition zoneNorberg, Karl January 2022 (has links)
Transition zones are changes in the track structure, detected by an abrupt deviationin track stiffness and/or differential settlements. One inevitable transition zone is thebridge approach. This study has investigated in this transition zone, adapted for highspeed,ballastless track. The aim was to observe the general behaviour of the transitionzone including its critical components, and to compare different measures, transitionconstructions, to manage with the eventual problems. A base model, called Nullmodel,was developed using the 3D finite element method to evaluate the behaviour of thetransition zone. Based on the Nullmodel, six comparative models have been created,including different types of transition constructions within the substructure. New forthis study is that it investigates the overall behaviour of the transition zone, and alsothe substitution of subballast in combination with approach blocks.For the general behaviour of the transition zone, the results have shown that theballastless track does not behave as a traditional ballasted track. Furthermore,the direction of travel affects the magnitude of different dynamical parameters.Comparing different transition constructions, replacing the subballast with ahydraulically bonded layer in combination with an approach block with cementbounded granular material is found to be the best alternative. Finally, the invertedapproach block is found to be an equally good, or better, mitigative measure incomparison with the regular approach block.
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The influence of torsional resistance of the deck on the dynamic response of a high-speed railway bridge : Case study: Ulla River ViaductSanroman Cervero, Claudia January 2017 (has links)
Understanding how different parameters affect the dynamic response of high-speed railway bridges is crucial to selecting an efficient structural form. Despite existing numerous publications within this field, only few address the importance of torsional deformations. The main objective of this thesis is to investigate the influence of the torsional resistance of the deck on the dynamic response of an existing bridge. Ulla River Viaduct is presented as a case study, allowing to analyse some aspects of its design and what their alteration entails. To this end, 6 different 3D FE models are compared, 5 of which show a modification from the original configuration. In addition, several positions of the train are considered to contrast the effects when the torsional modes are excited. The performed dynamic calculations are based on the implicit direct integration procedure. The analysis of the case study demonstrates the benefit of closing the torsional circuit of the deck. The results also evidence the need of including torsional effects in its dynamic assessment when low values of torsional rigidity are considered. All this is not easy when simplified 2D or 3D beam models are used. As a final remark, the original design of the Ulla River Viaduct is found highly efficient from a dynamical point of view.
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Brobanor och dess egenskaper för kommande höghastighetsjärnväg : Brobanors användning och egenskaper i samband med höghastighetsjärnväg / Bridge tracks and their characteristics for upcoming high-speed railway : Use and characteristics of bridge lanes in the context of high-speed railZubanovic, Haris, Saakyan, Hajk January 2023 (has links)
SammanfattningSvensk järnväg har aldrig varit mer belastad och trafikerad än idag, och värre kommer det att bli. Det har inte pågått några större investeringar i svensk järnväg sen 1990-talet, effekterna av den strategin börjar bli alltmer uppenbar. Sveriges järnvägssystem i jämförelse med många europeiska länder och även utanför Europa är teknologiskt och innovativt undermålig. Höghastighetståg som överstiger 250 km/h är ännu bara ett koncept i Sverige medan i länder som Frankrike, Tyskland, Kina och Japan är detta sen flera år tillbaka en verklighet. Det finns framträdande fördelar med etableringen av höghastighetsjärnväg som överstiger hastigheter på 250km/h. Utbyggnaden av höghastighetsjärnväg medför ett avsteg från konventionella järnvägsmetoder så som banvallar, i stället används prefabricerade broelement som möjliggör fast gjutning av spåret och utan användningen av ballast. Denna metod banar väg för högre tåghastigheter, mindre underhållsåtgärder, längre livslängd, passager under bron av befintlig transportinfrastruktur och besparing av natur och djurliv. Ovannämnda länder har kunnat omdirigera trafikbelastning på övriga transportsystem så som vägar och inrikes flygresor. En mindre belastning på exempelvis vägnätverket, leder till bättre trafikförhållanden, mindre slitage på vägbana och därmed sänkta kostnader för underhåll. Ur ett miljö- och hållbarhetsperspektiv minskar även utsläppet av farliga gaser och partiklar så som koldioxid, samt dämpar konsumtionen av fossila bränslen till fossildrivna fordon. Syftet med examensarbetet är att lyfta fördelarna med utbyggnaden av höghastighetsjärnväg i Sverige. Där fokus ligger i att göra detta genom att frångå den konventionella metoden av banvallar och i stället implementera brobanor med dess många framträdande fördelar. Arbetet genomsyras av utländska perspektiv gällande utbyggnad och underhåll, där höghastighetsjärnväg förlagd på bro används i större omfattning. Detta medför att arbetet kan erbjuda relevanta perspektiv från länder som exempelvis Kina som är världsledande inom området. Förhoppningen är att arbetet ska kunna användas som underlag för framtida järnvägsprojekt i Sverige. Resultatet för rapporten innehåller tre delar, kostnad, underhållsåtgärder samt miljö- och hållbarhetsperspektiv. Arbetet har redogjort för en grov kostnadsindikation på vad det kan kosta att bygga 1 km broförlagt ballastfritt dubbelspår, slutkostnaden hamnade på 929 miljoner kr med en standardavvikelse på ± 30 %. Underhåll av höghastighetsjärnväg på brobanor påvisas av många länder vara minimal. Det som möjliggör detta är innovativ detekteringsteknologi som regelbundet återger skick och funktionsduglighet av såväl banan som bron. Brobanor konstrueras för långa livslängder, det slitage som uppstår är generellt kopplat till rälsslipning och så kallade kritiska punkter vid sammanfogning av prefabricerade broelementen där det finns större risk för sprickbildning med mera. / Swedish railways have never been more congested than today, and it will get worse. There has been no major investment in Swedish railways since the 1990s, and the effects of that strategy are becoming increasingly apparent. Sweden's railway system, compared to many European countries and even countries outside Europe, is technologically and innovatively inferior. High-speed trains exceeding 250 km/h are still only a concept in Sweden, whereas in countries such as France, Germany, China, and Japan this has been a reality for several years. There are prominent advantages to the establishment of high-speed rail exceeding speeds of 250km/h. The development of high-speed rail involves a departure from conventional railway methods such as embankments, instead using prefabricated bridge elements that allow for the fixed casting of the track and without the use of ballast. This method paves the way for higher train speeds, less maintenance, longer service life, passage under the bridge of existing transport infrastructure, and conservation of nature and wildlife. The above-mentioned countries have been able to redirect traffic loads from other transport systems such as roads and domestic air travel. Less strain on the road network, leads to better traffic conditions, less wear and tear on the road surface and thus reduced maintenance costs. From an environmental and sustainability perspective, it also reduces emissions of hazardous gases and particulates such as carbon dioxide and curbs the consumption of fossil fuels by fossil fuel powered vehicles.The aim of the thesis is to highlight the benefits of the expansion of high-speed rail in Sweden. The focus is to do this by abandoning the conventional approach of embankments and instead implementing bridge lanes with its many prominent advantages. The work is permeated by foreign perspectives regarding development and maintenance, where high-speed rail on bridges is more widely used. This means that the work can offer relevant perspectives from countries such as China, which is world leading in this field. It is hoped that the work can be used as a basis for future railway projects in Sweden. The result of the report contains three parts, cost, maintenance measures and environmental and sustainability perspectives. The work has given a rough cost indication of what it might cost to build 1 km of bridge-laid ballastless double track, the final cost ended up at 929 million SEK with a standard deviation of ± 30%. Maintenance of high-speed rail on bridge tracks is shown by many countries to be minimal. This is made possible by innovative detection technology that regularly reproduces the condition and operability of both the track and the bridge. Bridge decks are designed for long lifetimes, the wear and tear that occurs is generally related to rail grinding and so-called critical points in the joining of prefabricated bridge elements where there is a higher risk of cracking etc.
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Vliv vysokorychlostních tratí na změny dostupnosti regionu Prahy / Impact of high-speed-rails to change the accessibility of Prague regionRandák, Jakub January 2015 (has links)
VLIV VYSOKORYCHLOSTNÍCH TRATÍ NA ZMĚNY DOSTUPNOSTI REGIONU PRAHY Abstrakt Předkládaná diplomová práce si klade za cíl diskutovat regionální dopady vysokorychlostní železnice v obecných souvislostech a dále s důrazem na změny dostupnosti. Dále si klade za cíl komplexně popsat změny dostupnosti Prahy po vybudování systému vysokorychlostní železnice v Česku s ohledem na dvě možná trasování úseku Praha - Brno. V neposlední řadě se tato práce věnuje studiu potenciální dostupnosti obcí Česka po vybudování vysokorychlostních tratí v Čechách, na Moravě a ve Slezsku. Vysokorychlostní železnice bude významnou páteří veřejné dopravy v Česku, ale umožní též kapacitní napojení české železniční sítě na zbytek Evropy. Hlavním nástrojem vlastního výzkumu jsou analýzy dostupnosti v prostředí GIS. Klíčová slova: vysokorychlostní železnice, Česko, Praha, regionální a lokální dopady, časová dostupnost, potenciální dostupnost IMPACT OF HIGH-SPEED-RAILS TO CHANGE THE ACCESSIBILITY OF PRAGUE REGION Abstract The aim of this diploma thesis is to discuss regional impacts of the high-speed railways in the general context with the emphasis on the issue of accessibility changes. Furthermore, the thesis concentrates on comprehensively description of changes in availability of Prague after the high-speed rail system in Czechia will be...
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Hodnocení změn dělby přepravní práce v souvislosti s výstavbou vysokorychlostní trati Praha-Brno / Assessment of Changes of the Modal Split in Connection with the Construction of High Speed Railway Prague-BrnoKoukal, Martin January 2018 (has links)
The aim of this diploma thesis is to discuss the assessment of changes of the modal split in connection with the construction of high speed railway Prague-Brno. Thesis is aimed on wider context of two theoretical concepts in transportation researches: travel behaviour and the value of travel time. Data collection took place in the form of "Paper and Pencil Interview" method. For a deeper analysis was used the Pivot Table tools. From the collected data was found that economically active people from coaches and trains have higher travel time than students. Among cars users the most important factor influencing the choice of traffic mode is the speed, for coach users it is price and for train users the posibility of work/rest during the journey. Assuming a reduction of travel time between Prague and Brno for about 1 hour while keeping the fare price about CZK 200, high-speed rail connections has the potential to generate more frequent journeys among existing passengers. Keywords: modal split, travel behaviour, the value of travel time savings, competitiveness of railways, high speed railway
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Wireless channel estimation and channel prediction for MIMO communication systemsTalaei, Farnoosh 22 December 2017 (has links)
In this dissertation, channel estimation and channel prediction are studied for wireless communication systems. Wireless communication for time-variant channels becomes more important by the fast development of intelligent transportation systems which motivates us to propose a reduced rank channel estimator for time-variant frequency-selective high-speed railway (HSR) systems and a reduced rank channel predictor for fast time-variant flat fading channels. Moreover, the potential availability of large bandwidth channels at mm-wave frequencies and the small wavelength of the mm-waves, offer the mm-wave massive multiple-input multiple-output (MIMO) communication as a promising technology for 5G cellular networks. The high fabrication cost and power consumption of the radio frequency (RF) units at mm-wave frequencies motivates us to propose a low-power hybrid channel estimator for mm-wave MIMO orthogonal frequency-division multiplexing (OFDM) systems.
The work on HSR channel estimation takes advantage of the channel's restriction to low dimensional subspaces due to the time, frequency and spatial correlation of the channel and presents a low complexity linear minimum mean square error (LMMSE) estimator for MIMO-OFDM HSR channels. The channel estimator utilizes a four-dimensional (4D) basis expansion channel model obtained from band-limited generalized discrete prolate spheroidal (GDPS) sequences. Exploiting the channel's band-limitation property, the proposed channel estimator outperforms the conventional interpolation based least square (LS) and MMSE estimators in terms of estimation accuracy and computational complexity, respectively. Simulation results demonstrate the robust performance of the proposed estimator for different delay, Doppler and angular spreads.
Channel state information (CSI) is required at the transmitter for improving the performance gain of the spatial multiplexing MIMO systems through linear precoding.
In order to avoid the high data rate feedback lines, which are required in fast time-variant channels for updating the transmitter with the rapidly changing CSI, a subframe-wise channel tracking scheme is presented. The proposed channel predictor is based on an assumed DPS basis expansion model (DPS-BEM) for exploiting the variation of the channel coefficients inside each sub-frame and an autoregressive (AR) model of the basis coefficients over each transmitted frame. The proposed predictor properly exploits the channel's restriction to low dimensional subspaces for reducing
the prediction error and the computational complexity. Simulation results demonstrate
that the proposed channel predictor out-performs the DPS based minimum energy (ME) predictor for different ranges of normalized Doppler frequencies and has better performance than the conventional Wiener predictor for slower time-variant channels and almost the similar performance to it for very fast time-variant channels with the reduced amount of computational complexity.
The work on the hybrid mm-wave channel estimator considers the sparse nature of
the mm-wave channel in angular domain and leverages the compressed sensing (CS)
tools for recovering the angular support of the MIMO-OFDM mm-wave channel. The angular channel is treated in a continuous framework which resolves the limited
angular resolution of the discrete sparse channel models used in the previous CS based
channel estimators. The power leakage problem is also addressed by modeling the
continuous angular channel as a multi-band signal with the bandwidth of each sub-band
being proportional to the amount of power leakage. The RF combiner is designed
to be implemented using a network of low-power switches for antenna subset selection
based on a multi-coset sampling pattern. Simulation results validate the effectiveness
of the proposed hybrid channel estimator both in terms of the estimation accuracy
and the RF power consumption. / Graduate
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