Sökning: "crossings"

Visar resultat 6 - 10 av 87 avhandlingar innehållade ordet crossings.

  1. 6. Wheel–Rail Impact Loads and Track Settlement in Railway Crossings

    Författare :Xin Li; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vehicle--track dynamics; wheel--rail contact; track settlement; material modelling of ballast; Switches and crossings; turnout; cyclic loading; Green s functions;

    Sammanfattning : Turnouts (Switches & Crossings, S&C) are critical components of a railway track requiring regular maintenance and generating high life cycle costs. A main driver for the high maintenance costs is the need to repair and replace switch rails and crossings as these components are subjected to a severe load environment. LÄS MER

  3. 7. The use of highway crossings to maintain landscape connectivity for moose and roe deer

    Författare :Mattias Olsson; Per Widén; Anthony Clevenger; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; wildlife crossings; Barrier effect; habitat selection; ecoduct; moose; roe deer; connectivity; conservation; overpass; underpass; highway; exclusion fencing; Biology; Biologi; Biology; Biologi;

    Sammanfattning : Increasingly wildlife managers and land managers are challenged to maintain the viability and connectivity among large mammal populations. Thus, it is important that effective highway crossings are identified and optimized with respect to construction cost, facilitation of ungulate movements, and ability to reduce wildlife-vehicle collisions. LÄS MER

  4. 8. Optimisation of Railway Switches and Crossings

    Författare :Björn Pålsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wheel and rail wear; railway turnout; optimisation; switch crossing; dynamic vehicle-turnout interaction;

    Sammanfattning : Methods for simulation-based optimisation of the design of railway turnouts (switches & crossings, S&C) are developed and demonstrated. Building on knowledge of dynamic wheel–rail interaction in turnouts, it is investigated how rail profile degradation can be reduced by the optimisation of geometry and component stiffness of the track superstructure. LÄS MER

  5. 9. Squat Detection in Railway Switches & Crossings Using Point Machine Vibration

    Författare :Yang Zuo; Matti Rantatalo; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Drift och underhållsteknik; Operation and Maintenance;

    Sammanfattning : Railway switches and crossings (S&Cs) are among the most important high-value components in a railway network and a single failure of such an asset could result in severe network disturbance, huge economical loss, and even severe accidents. Therefore, potential defects need to be detected at an early stage and the status of the S&C must be monitored to prevent such consequences. LÄS MER

  7. 10. Towards an efficient use of infrastructure and the built environment : Essays in transport and housing economics

    Författare :Lina Jonsson; Fastighetsvetenskap; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Hedonic pricing; Noise; Railway traffic; Road traffic; Congestion pricing; Acceptability; Road user charging; Political Economy; Railway; Marginal cost; Accident probability; Level crossings; Housing Economics; Property tax;

    Sammanfattning : All four papers in the thesis share a common theme: how to achieve an efficient use of infrastructure and the built environment. In the presence of externalities, pricing according to the (short-run) marginal cost is one answer on how this can be achieved and the first two papers estimates parts of the marginal cost of traffic. LÄS MER