Sökning: "heavy haul"

Visar resultat 11 - 15 av 21 avhandlingar innehållade orden heavy haul.

  1. 11. Cognitive work analysis in practice : Adaptation to project scope and industrial context

    Författare :Ida Bodin; Anders Jansson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Datavetenskap med inriktning mot människa-datorinteraktion; Computer Science with specialization in Human-Computer Interaction;

    Sammanfattning : The Cognitive Work Analysis (CWA) framework is widely used by researchers for the analysis of complex systems. It, however, lacks the same impact amongst industrial practitioners. This thesis investigates possible adaptations of the framework to project and industrial constraints, and the consequences associated with such adaptations. LÄS MER

  3. 12. Modelling of cyclic and viscous behaviour of pearlitic steels. Application to tread braked railway wheels

    Författare :Ali Esmaeili; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Railway wheels; viscoplasticity; tread braking; rolling contact fatigue; full-scale brake rig testing; finite element analysis; plasticity;

    Sammanfattning : Railway wheel and rail materials are subjected to very high stresses and, in some cases, also elevated temperatures. The rolling contact loading results in a multiaxial stress state with a combination of compression and shear. LÄS MER

  4. 13. The Influence of Customer Agreements and Planning Principles on Rail Freight Performance

    Författare :Lars Backåker; Lundgren Jan; Johanna Törnquist Krasemann; Stefan Engevall; Markus Bohlin; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Rail freight planning; trip plan generation; routing and scheduling; dynamic assignment;

    Sammanfattning : Rail freight transportation is recognized worldwide as a suitable transportation mode when it comes to long haul transportation of heavy commodities. The industry is also known to be capital intensive, highly dependent on infrastructural developments and requires thorough planning of operations. LÄS MER

  5. 14. Effects of top-of-rail friction modifiers on the friction, wear and cracks of railway rails

    Författare :Saad Ahmed Khan; Jan Lundberg; Rolf Dollevoet; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Drift och underhållsteknik; Operation and Maintenance;

    Sammanfattning : The railway is an economical and environmentally friendly mode of transport for long distances and heavy loads. The demands on the operators are increasing with increased competition in the market, and therefore they are currently demanding more track capacity. In the short term, the existing network is expected to deliver the increased capacity. LÄS MER

  7. 15. Modelling of cyclic and viscous behaviour of thermomechanically loaded pearlitic steels; Application to tread braked railway wheels

    Författare :Ali Esmaeili; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rolling contact fatigue; plasticity; tread braking; full-scale brake rig testing; Railway wheels; finite element analyses; pearlitic steel; viscoplasticity; ratchetting; phase transformations;

    Sammanfattning : In service, railway wheel and rail materials are subjected to high stresses and, in some cases, elevated temperatures. The high stresses are caused by the rolling contact between wheel and rail. Furthermore, heat generated from tread braking and/or sliding between wheel and rail gives additional stress due to constrained thermal expansion. LÄS MER