National Repository of Grey Literature 55 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Integration of the tram line into the city structure
Škopková, Klára ; Plášek, Otto (referee) ; Valehrach, Jan (advisor)
Tram transport is an integral part of public transport in many cities. Its lines run through a variety of environments. The integration of tram line into the urban environment – urban structures – is the focus of this thesis. The aim of this thesis is to find out in several Czech and foreign cities how the tramway is integrated in different urban structures. And then, for the analysed cities, to identify and compare their approaches to tramway lines in different urban structures.
Reconstruction of the Opatov railway station
Živný, David ; Rotschein, Petr (referee) ; Plášek, Otto (advisor)
he aim of the diploma thesis was to design the reconstruction of the railway station. Opatov including the adjacent parts of the intermediate sections. In the design it is necessary to remove the speed limitation of the station and to achieve the continuous speed of 160 km/h at least for the V150 and Vk speed profiles. Other objectives are the extension of the tracks in the station for trains 740 m long, the installation of platforms allowing barrier-free access and the replacement of the level crossing at km 234.997 with an out-of-level crossing. The work includes the restoration of the railway superstructure and substructure according to the applicable standards and regulations, its drainage and a bill of quantities.
Switch and Crossing Design for High Speed Lines
Raif, Lukáš ; Šestáková,, Janka (referee) ; Plášek, Otto (advisor)
Different requirements for track structures, switches and crossings have recently gained prominence, in part, due to preparations of high-speed lines across the Czech Republic. High-speed turnouts must fulfil many criteria, because the speeds on main line turnouts normally reach between 250 and 350 km/h. The main requirement, which most structural modifications and turnout improvements deal with, is to reduce dynamic load. The PhD thesis aims to research in particular possibilities for reducing dynamic load caused by passing vehicles; primarily by track stiffness optimization by fastening system modifications. The work is based on the observation of a test section in Ústí nad Orlicí railway station, where switches and crossings with modified fastening systems were installed. The evaluation is then used as a basis for designing of a rail fastening system to optimize the track stiffness in high-speed switches and crossings to reduce the dynamic effects.
Track Quality Evaluation
Joudal, Daniel ; Volejník, Miloslav (referee) ; Plášek, Otto (advisor)
This bachelor’s thesis is focused on comparison of two track geometry parameters quality evaluation methods. The compared methods are CZK, track quality index currently used in the Czech Republic, and TUG, track quality index developed at the Graz technical university in 2020. Data from the measuring carriages provided by Správa železnic (the Czech Republic’s infrastructure manager) were processed using the Matlab programme. There were three railway track section embraced in the thesis: Malšice – Sudoměřice, Sklené – Křižanov and Velim – Kolín. Track quality index graphs were made for all three railway stretches using both CZK and TUG methods, that were then compared.
Tram Transport Serving as a City-forming Element
Csiba, Emese ; Plášek, Otto (referee) ; Valehrach, Jan (advisor)
The topic of this bachelor thesis is the description of existing solutions of individual structures in the field of tram transport. It is a catalogue of possible solutions for tram lines and stops and their basic comparison. The thesis includes analyses of existing designs of stops, alignments of different types of track, etc. and their assessment in terms of creating public spaces with tram transport.
Interaction between Bridge Structure and Continuous Welded Rail
Vendel, Jiří ; Salajka, Vlastislav (referee) ; Ryjáček,, Pavel (referee) ; Plášek, Otto (advisor)
Understanding the interaction between a continuous welded rail and bridge structure is knowledge of all influences that participate in mutual coaction. Besides the material and cross-sectional characteristics of the bridge belonging to the scope of bridge design, there are several circumstances derived from external loads which have to be taken into account when designing new systems and assessing existing ones. From the physical point of view, each material has a natural tendency to change in length when the internal temperature changes. The continuous welded rail, concretely its central fixed zone, does not have this possibility due to its principle. However, if it is located on a bridge that freely expanse, the situation is significantly different. Due to the thermal expansion as well as the effects of railway transport, the bridge contributes significantly to the position and stress of the track. Usually, the most observed part of the continuous welded rail is the area above the sliding bearings of the bridge, where extremes of displacement and stress occur. Not only longitudinal expansion but also the rotation of the end of the supporting structure are the main sources of stresses at this point. This is because of the vertical load of the railway combined with the effects of traction and braking. If the exact degree of interaction between the bridge structure and the track (known as the longitudinal resistance of the track) were known, the design of a new or assessment of the existing system would have a better informative value, and we would not commit undesirable inaccuracies resulting from general normative provisions. It has been tested by many years of experience that from an operational and economic point of view, it is undoubtedly advantageous and desirable to establish a continuous welded rail wherever circumstances allow. So the goal of the research efforts is to approach more faithfully the real length limits of the bridge structure, in which
Development of Long-pitch Corrugation in Curves of Small Radii
Valehrach, Jan ; Kohout,, Martin (referee) ; Lidmila,, Martin (referee) ; Plášek, Otto (advisor)
Throughout the operation, the rails are worn and deteriorate. With the increasing speed of rolling stock, along with higher track loads and especially in the vicinity of major traffic hubs with a higher frequency of trains, defects that did not occur to such an extent before or were not considered to be significant, are brought to the forefront of the concerns of track infrastructure managers. Even though these defects are not directly restrictive to traffic operation, they are, in any case, a source of noise and vibration. One of these defects on the railway track is the micro-geometry defect of the running surface of the railhead. In directional curves with radii of less than 600 m or 700 m, defects known as long-pitch corrugation occur on the inner rail. In curves with 300 m or smaller radii, these waves are so distinct that they are a significant source of noise and vibration. In particular, vibrations affect the track surroundings and the track itself, as they cause other defects in the track structure. This dissertation deals with long-pitch corrugation, focusing on the monitoring of wave generation and development over time. The verification of the possibility to track the development of slip waves over time is the basis for possible future models predicting the development of defects. Numerous measurements of geometric parameters of the track and microgeometry of the railheads, specifically slip waves, have been carried out in the framework of the problem. Using RMS and peak-to-peak methods, the rate of development of defects over time and the relationship with other track parameters were evaluated. Based on the obtained development curves, intervals for further maintenance interventions were estimated. A part of the thesis focuses on the deficiency or excess of cant concerning the development of long-pitch corrugation.
Train Identification System at Railway Switches And Crossings Using Advanced Machine Learning Methods
Krč, Rostislav ; Vorel,, Jan (referee) ; Plášek, Otto (referee) ; Podroužek, Jan (advisor)
This doctoral thesis elaborates possibilities of automatic train type identification in railway S&C using accelerometer data. Current state-of-the-art was considered, including requirements stated by research projects such as S-Code, In2Track or Turnout 4.0. Conducted experiments considered different architectures of artificial neural networks (ANN) and statistically evaluated multiple use case scenarios. The resulting accuracy reached up to 89.2% for convolutional neural network (CNN), which was selected as a suitable baseline architecture for further experiments. High generalization capability was observed as models trained on data from one location were able to classify locomotive types in the other location. Further experiments evaluated the effect of signal filtering and denoising. Evaluation of allocated memory and processing time for pre-trained models proved feasibility for in-situ application with regard to hardware restrictions. Due to a limited amount of available accelerometer data, distribution grid power demand data were utilized for further refinement of the proposed CNN architecture. Deep multi-layer architecture with regularization techniques such as dropout or batch normalization provides state-of-the-art performance for time series classification problems. Class activation mapping (CAM) allowed an explanation of decisions made by the neural network. Presented results proved that train type identification directly in the S&C is possible. The CNN was selected as optimal architecture for this task due to high classification accuracy, automatic filtration, and pattern recognition capabilities, allowing for the incorporation of the end-to-end learning strategy. Moreover, direct on-site application of pre-trained models is feasible with respect to limitations of in-situ hardware. This thesis contributes to understanding the train type identification problem and provides a solid theoretical background for future research.
Rail wear in track curves of small radii
Schneider, Martin ; Szabó, Petr (referee) ; Plášek, Otto (advisor)
The diploma thesis deals with a rail wear in curves with a small radius (R < 500 m), in the national corridor railway, between stations Blansko and Svitavy. The diploma thesis deals with the impact of the track gradient, the horizontal layout of the track, traffic composition, and direction of travel on the size of the horizontal and vertical rail wear. Also, the influence of rail steel grade is discussed in the diploma thesis.
Optimization of track section Olomouc - Šumperk km 25.7 - 28.652
Živný, David ; Louma, Jaroslav (referee) ; Plášek, Otto (advisor)
This bachelor thesis aims to design a reconstruction of the track section Olomouc - Šumperk km 25,7 - 28,652. Part of the thesis is a renewal of railway superstructure and substructure that are must meet the requirements according to current standards and regulations, establishments of drainage, technological workflow proposal and bill of quantities. The Bachelor thesis is also devoted to geometric parameters of the track.

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