Search for dissertations about: "railway tracks"

Showing result 21 - 25 of 44 swedish dissertations containing the words railway tracks.

2. 21. Towards optimal railway track utilization based on societal benefit

   Author : Victoria Svedberg; Aronsson Martin; Martin Joborn; Jan T. Lundgren; Linköpings universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Infrastructure managers in railway systems are striving to have as efficient track utilization as possible. There are no unanimous interpretation of efficiency in terms of track utilization, but the aim of the Swedish Transport Administration is to allocate track capacity such that societal benefit is maximized. READ MORE

4. 22. Automating condition monitoring of vegetation on railway trackbeds and embankments

   Author : Roger G. Nyberg; Narendra K. Gupta; Mark S. Dougherty; Siril Yella; David J. Murray-Smith; Alistair Armitage; Högskolan Dalarna; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Complex Systems – Microdata Analysis; Komplexa system - mikrodataanalys;

   Abstract : Vegetation growing on railway trackbeds and embankments present potential problems. The presence of vegetation threatens the safety of personnel inspecting the railway infrastructure. In addition vegetation growth clogs the ballast and results in inadequate track drainage which in turn could lead to the collapse of the railway embankment. READ MORE

5. 23. Random railways and cycles in random regular graphs

   Author : Hans Garmo; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Random railway; connectivity number; random regular graph; long cycles; asymptotic distribution. 1991 Mathematics Subject Classification. Primary 60F05; 60C05; 05C38; 05C80; 05C40; 05C45; MATEMATIK; MATHEMATICS; MATEMATIK; matematisk statistik; Mathematical Statistics;

   Abstract : In a cubic multigraph certain restrictions on the paths are made to define what is called a railway. Due to these restrictions a special kind of connectivity is defined. As the number of vertices tends to infinity, the asymptotic probability of obtaining an, in this sense, connected random cubic multigraph is shown to be 1/3. READ MORE

6. 24. Towards Model-Based Condition Monitoring of Railway Switches and Crossings

   Author : Marko Milosevic; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sleeper void; Switches crossings; condition indicators; embedded sleeper accelerometer; multi-body simulations; dynamic vehicle–track interaction; MBS; S C; wheel–rail contact forces; condition monitoring; crossing rail geometry; displacement reconstruction.; model calibration;

   Abstract : Railway switches and crossings (S&C, turnouts) connect different track sections and create a railway network by allowing for trains to change between tracks. This functionality comes at a cost as the load-inducing rail discontinuities in the switch and crossing panels cause much higher degradation rates for S&C compared to regular plain line track. READ MORE

7. 25. Dynamic Train/Track Interaction: Simulation of Railhead Corrugation Growth under a Moving Bogie Using Mathematical Models Combined with Full-Scale Measurements

   Author : Annika Igeland; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; railhead corrugation growth; railway and track irregularities; railway dynamics and measurements; train track interaction; complex-valued modal analysis;

   Abstract : Heavier trains and higher speeds have increased the need for high-quality tracks and vehicles in order to fulfill safety and environmental requests. The phenomena involved in dynamic train/track interaction lead to noise radiation, induce ground-borne vibrations and degrade the track structure and the railcar wheels. READ MORE