Sökning: "commuter"

Visar resultat 11 - 15 av 26 avhandlingar innehållade ordet commuter.

1. 11. Factors that influence choice of travel mode in major urban areas

   Författare :Anna-Lena Lindström Olsson; KTH; []
   Nyckelord :mode choice; valuation; traffic reduction; stated preference; factors; park and ride;

   Sammanfattning : Problems associated with traffic, such as traffic congestionand pollution, have occurred in major urban areas in particulardue to the increased use of cars. One possible way to reducethe use of cars is to replace commuter trips by car with othermodes of transport, such as a combination of car and publictransport called Park&Ride. LÄS MER

3. 12. On Discharge Strategies for Plug-in Hybrid Electric Vehicles

   Författare :Viktor Larsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Route Recognition; Energy Management; Dynamic Programming; Hybrid Electric Vehicles; Plug-in Hybrid Electric Vehicles;

   Sammanfattning : During recent years electrification of vehicles has emerged as a promisingtechnology to reduce oil dependency and CO2 emissions within the transportationsector. At the present day several automotive manufacturers areabout to introduce plug-in hybrid electric vehicles to the market, i.e. LÄS MER

4. 13. Out-of-Round Railway Wheels - Causes and Consequences An Investigation Including Field Tests, Out-of-Roundness Measurements and Numerical Simulations

   Författare :Anders Johansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polygonalization; wheel flat; full-scale measurements; wear modelling; impact load detector; railway wheel out-of-roundness; wheel removal criterion; dynamic train-track interaction; corrugation;

   Sammanfattning : Causes and consequences of out-of-round railway wheels are investigated through literature studies, full-scale field experiments, out-of-roundness measurements, and numerical simulations. Both defects around the complete wheel circumference (e.g. polygonal wheels with wavelengths up to one wheel circumference) and local defects (e. LÄS MER

5. 14. Label Cover Reductions for Unconditional Approximation Hardness of Constraint Satisfaction

   Författare :Cenny Wenner; Johan Håstad; Viggo Kann; Irit Dinur; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Combinatorial Optimization; Complexity Theory; Approximation; Approximability; Inapproximability; Computational Hardness; NP; Optimization; Constraint Satisfaction; Kombinatorisk optimering; Komplexitetsteori; Beräkningsteori; Approximation; Approximerbarhet; Beräkningssvårighet; NP; Optimering; Vilkorssatisfiering; Vilkorsuppfyllning; Vilkorstillfredställand; datalogi; Computer Science;

   Sammanfattning : Combinatorial optimization include such tasks as finding the quickest route to work, scheduling jobs to specialists, and placing bus stops so as to minimize commuter times. We consider problems where one is given a collection of constraints with the objective of finding an assignment satisfying as many constraints as possible, also known as Constraint Satisfaction Problems (CSPs). LÄS MER

7. 15. On wear in rolling/sliding contacts

   Författare :Rickard Nilsson; Ulf Olofsson; I. Sherrington; KTH; []
   Nyckelord :Technology; wear; rolling; sliding; contact; environment; TEKNIKVETENSKAP; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : The aim of this thesis is to increase the understanding of wear in rolling/sliding contacts such as the wheel-rail contact for railroads and the roller-washer contact for roller bearings. The Stockholm commuter train network has been the subject of papers A and B in this thesis in which the wear and surface cracks on rails has been observed for a period of three years. LÄS MER