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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Characterisation of particulate matter emissions from motor vehicles /

Welburn, Colin T. January 1900 (has links)
Thesis (M. Eng.)--Carleton University, 2001. / Includes bibliographical references (p. 211-219). Also available in electronic format on the Internet.
62

A vehicle stability on combined horizontal and vertical alignments /

Furtado, Glen January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2002. / Includes bibliographical references (p. 176-185). Also available in electronic format on the Internet.
63

Particle size distribution measurements of light duty motor vehicle exhaust : evaluating different measurement techniques and vehicle technologies /

Tracey, Kristine January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2002. / Includes bibliographical references (p. 129-131). Also available in electronic format on the Internet.
64

Integrated vehicle positioning system using sensors and image processing of beacon signal /

Liu, Hugh-sing, Hugh. January 2000 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2000.
65

Controlling vehicular emissions in an era of rapid motorization a case study of Guangzhou /

Lee, Ka-yin, Anna. January 2009 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 169-207). Also available in print.
66

A systems engineering approach to the design of a vehicle navigation system /

MacDonald, Vincent J. January 1993 (has links)
Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1993. / Abstract. Includes bibliographical references (leaves 81-84). Also available via the Internet.
67

Resume of tests on commercial vehicles on winter surfaces, 1939-1966, National Safety Council Committee on Winter Driving Hazards

Hajela, Gyaneshwar Prasad, January 1966 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record.
68

Improving the energy density of hydraulic hybridvehicle (HHVs) and evaluating plug-in HHVs /

Zeng, Xianwu. January 2009 (has links)
Thesis (M.S.)--University of Toledo, 2009. / Typescript. "Submitted as partial fulfillment of the requirements for The Master of Science in Mechanical Engineering." "A thesis entitled"--at head of title. Bibliography: leaves 75-78.
69

Development of predictive methods for tiltrotor flows

Jimenez-Garcia, Antonio January 2018 (has links)
This thesis presents evidence on the ability of grid-based, Computational Fluid Dynamics methods based on the Unsteady Reynolds Averaged Navier-Stokes equations to accurately predict axial flight performance of rotors with modest computer resources. Three well-studied blades, the B0-105, S-76, and PSP main rotor blades, are used and results are compared with experimental data. Likewise, performance analyses of the JORP propeller and XV-15 tiltrotor blades are carried out, respectively, aiming to validate the employed CFD method for such relevant flows. Validation of the HMB3 CFD solver for complete tiltrotors is also presented. The aim is to assess the capability of the present CFD method in predicting tiltrotor airloads at different flight configurations. In this regard, three representative cases of the ERICA tiltrotor were selected, corresponding to aeroplane, transition corridor, and helicopter modes, covering most modes of tiltrotor flight. Aerodynamic optimisation of tiltrotor blades with high-fidelity computational fluid dynamics coupled with a discrete adjoint method is also carried out. This work shows how the main blade shape parameters influence the optimal performance of the tiltrotor in helicopter and aeroplane modes, and how a compromise blade shape can increase the overall tiltrotor performance. Finally, the implementation and validation of an efficient, high-order, finite-volume scheme (up to 4th-order of spatial accuracy) in the HMB3 CFD solver is presented. The scheme shows a higher level of accuracy if compared with the standard-MUSCL, and 4th-order accuracy was achieved on Cartesian grids. Furthermore, a significantly high spectral resolution (dispersion and dissipation) of the new scheme is observed. Two-and three-dimensional test cases were considered to demonstrate the new formulation. Results of the steady flow around the 7AD, S-76, JORP propeller, and XV-15 blades showed a better preservation of the vorticity and higher resolution of the vortical structures compared with the standard MUSCL solution. The method was also demonstrated for three-dimensional unsteady flows using overset and moving grid computations for the UH-60A rotor in forward flight and the ERICA tiltrotor in aeroplane mode. For medium grids, the new high-order scheme adds CPU and memory overheads of 22% and 23%, respectively. The parallel performance of the scheme is fair but can be further improved.
70

Robust feedback control of flow separation using plasma actuators

Pasquale, Laura January 2017 (has links)
This thesis addresses the problem of controlling the unsteady flow separation over an aerofoil using plasma actuators, with the aim of improving the performance of fluid systems through the use of robust feedback controllers. Despite the complexity of the dynamics of interest, it is shown how the problem of controlling flow separation can be successfully formulated and solved as a simple output regulation problem. First, a novel control-oriented reduced-order model for nonlinear systems evolving on attractors is obtained. Its application to the incompressible Navier-Stokes equations is proposed, in order to obtain a linear reduced-order model (whose state variables have a clear and consistent physical meaning) of the complex flow/actuator dynamics. On the basis of the proposed model, a new robust multivariable feedback control algorithm for flow separation suppression is designed, using real-time velocity measurements, which are available in realistic applications. The presented control scheme is tested in both Single-Input-Single-Output (SISO) and Multi-Input-Multi-Output (MIMO) configurations, thus allowing for optimising the closed-loop system, with the aim of selecting suitable numbers and positions of the actuator/sensor pairs along the aerofoil, as well as desired references for the real-time measurements, according to the specific application (e.g., flow separation suppression, mixing enhancement etc.). Accurate numerical simulations of incompressible flows around both 2D aerofoils and 3D wings are performed in order to optimise the closed-loop system and illustrate the effectiveness of the proposed approach in the presence of complex dynamics that are neglected at the design stage. Robust performances, with respect to both parameter variations (e.g. geometry of the domain and Reynolds number) and model uncertainties, are demonstrated. The designed controller is able to effectively suppress the flow separation along the aerofoil, as well as the shedding vortices, thus yielding both a reduction of the drag and an increase of the lift. This allows for stall avoidance and increased efficiency.

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