Sökning: "Peter Torstensson"

Hittade 4 avhandlingar innehållade orden Peter Torstensson.

1. 1. Rail Corrugation Growth on Curves

   Författare :Peter Torstensson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; simulation; track and wheelset structural flexibility; small radius curves; short-pitch rail corrugation; dynamic vehicle–track interaction; test rig and field measurements; wear;

   Sammanfattning : Short-pitch rail corrugation that may develop on the low (inner) rail on small radius curves causes increased noise and vibration levels on railway networks worldwide. In lack of a generally applicable treatment, track authorities are forced to run expensive rail grinding programs on a regular basis to manage these problems. LÄS MER

3. 2. Rail Corrugation Growth on Curves

   Författare :Peter Torstensson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; short-pitch rail corrugation; rotating flexible wheelset model; small radius curves; prediction of long-term roughness growth; plastic deformation; non-Hertzian and non-steady wheel‒rail contact; wear; rutting corrugation;

   Sammanfattning : The development of periodic irregularities with distinct wavelengths (corrugation) on the low rail of small radius curves is studied through mathematical modelling, numerical simulations, field measurements and laboratory investigations. One year of monitoring of roughness on the low rail of a 120 m radius curve on the metro of Stockholm Public Transport (SL) showed severe growth of rail corrugation with wavelengths of about 5 cm and 8 cm. LÄS MER

4. 3. The population dynamics of Spergularia marina on a Baltic seashore meadow

   Författare :Peter Torstensson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis presents the demography and population dynamics of the annual halophyte Spergularia marina on a Baltic seashore meadow. The object of the investigation was to study the variation in demographical attributes by using a site-by-site comparison during four consecutive years. LÄS MER

5. 4. Quality-driven logistics

   Författare :Roy Andersson; Högskolan i Borås; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TQM; risk management; supply chain; demand chain; agile; six sigma; lean; quality management;

   Sammanfattning : The overall objective of this thesis is to describe and explain how different quality management philosophies can be combined in the supply/demand chain, in order to contribute to its resilience. The analysis is both quantitative and qualitative, based on theory and literature related to TQM, Lean, Agile and Six Sigma, one literature study and three case studies that were performed in companies. LÄS MER