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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.
131

X-by-wireless: a novel approach to vehicle control

Hoelscher, David Louis 15 May 2009 (has links)
As the cost of wireless devices approaches zero, it becomes more feasible to replace wires with wireless communication. Vehicle wiring harnesses are traditionally wired to communicate both power and information simultaneously, resulting in separate circuits for each vehicle device. X-By-Wireless seeks to supplant this configuration in favor of a shared power bus and wireless inter-component communication. In doing so, we can recognize a number of benefits such as reduced weight and increased reliability, flexibility, and upgradeability. However, this introduces new problems such as longer transmission delays, interference and encryption issues, fusing difficulties, and public perception regarding safety. The purpose of this thesis is to define the X-By-Wireless concept and to investigate the benefits and drawbacks in implementing X-By-Wireless. Furthermore, we do a theoretical and case study analysis to expand upon the weight reduction benefit so as to quantify the expected improvements. We also address each of the challenges presented by X-By-Wireless and integrate them into a proposed circuit that is capable of performing all the necessary functions of wireless control, wireless sensing, and fusing. We find that the proposed device can be mass-produced as an effective solution that meets the speed and security constraints necessary for most vehicle components.
132

Correlation between Fatigae of Automotive Wheel Centre - Discs and Hour-glass Laboratory Specimen

McGrath, PJ, Hattingh, DG, James, MN 29 December 2009 (has links)
Fatigue testing of complete automotive wheels is carried out on rotary bendmachines. These commercial mac hin e s s imulnt e h ar d - c o rn e rin g c o n ditio n s an d mainly testthefatigue performance of the central section of an automotive wheel' . This paper develops a relationship for predicting the fatigue performance of the wheel,based onfatigue tests of hourglass specimens machinedfrom centre discs. This is more economical of material and, in principle, also allows the effect on fatigue performance of change inproduction parameters or starting alloy to be assess ed, by c o n sid e rin g a limit e d numb e r of w h e e I blanks take n from each stage of the production process. This is p ote ntially a v ery u s eful to ol in optimisin g mat e rial selection, wheel design and production parameters. The p arti c ular c e ntr e - dis c un d e r c o n s id e r atio n i s manufactured from a dual-phas e ste eI (DP S)2 . Good c o rr elatio n w as achie v e d b e tw e e n S - lr.' data fr o m th e automotiv e w he els qnd that from the ho urglas s (H G) specimens.
133

Active control of vibrations transmitted through a car suspension

Roumy, Jean-Gabriel January 2003 (has links)
The vibrations caused by road imperfections, which are transmitted to a car frame through the suspension, are one of the major sources of ambient noise inside the passenger compartment of an automobile. / A solution to this problem is the addition of feedback-controlled actuators between the suspension attachment points and the car frame. These actuators can be driven to provide an active control of the vibrations, thus reducing greatly the magnitude of the forces exerted on the car frame at the suspension attachment points. In order to implement a robust yet effective controller, a model of a ¼ car suspension (suspension associated to a single wheel) is derived from experimentally acquired data. The structure's modal parameters are extracted from Frequency Response data, and are used to obtain a state-space realization. The performance of controller design techniques such as LQR and Hinfinity is assessed through simulation using the model of the suspension.
134

Design of a decision support system for dynamic truck dispatching

Taylor, Wendi Lyn 12 1900 (has links)
No description available.
135

FPGA driven synthesis employing a self-testing VLSI controller implementation as a case study

Hold, Betina K. January 1994 (has links)
This thesis formulates, and implements an automotive Anti-lock Brake System (ABS), reporting on its design simulation, synthesis, and eventual layout steps, from which extensions are drawn towards digital onto controllers FPGA technology, and the potential migration of the design onto ASIC technology. Implementation/environment fine-tuning of embedded controllers as such necessitate quickly prototyped circuit realizations. Examination of its functionality, real-time response, implementation, and testability is performed in an attempt to measure the usefulness of higher level design entry facilities such as VHDL in a rapid prototyping environment. Continuous on-line testing is included using aperiodic sample injections where the resultant generated values are compared to signatures known a priori, without compromising functionality. The achievable area and timing aid in the determination of the efficiency of the process and provide fuel for an FPGA and/or ASIC migration path for eventual implementation. Commentaries and generalized methodologies are assembled from the design's simulation, synthesis and layout utilizing VHDL and FPGAs, illustrating CAD tool capabilities/requirements/limitations, with respect to real-time synthesis and rapid prototyping of general controller applications involving asynchronous elements. (Abstract shortened by UMI.)
136

Network vehicle routing problems

Zhang, Xinglong 08 1900 (has links)
No description available.
137

Trucks and urban congestion

Trimble, Otis Marion 08 1900 (has links)
No description available.
138

British factory - Japanese transplant : an ethnographic study of workplace relations

Delbridge, Rick January 1995 (has links)
No description available.
139

An empirical study of future changes in the European car industry

Neidl, Johann Xaver January 2001 (has links)
The automotive supplier industry and the relationship between car manufacturers and suppliers has been confronted with major changes resulting from OEMs' strategy of stronger product integration and the building of so-called systems, sub-systems and components and segmentation of the supplier industry. Former valid work processes, division of work, organisational structures and also, the general manufacturer-supplier relationship has been subject to intensive evaluation and appropriate adaptation to the changed circumstances. This research project aims to investigate these changes in the European car industry in greater detail, particularly: The OEMs' system-building strategy What requirements OEMs must meet at the individual supplier levels (system, sub-system, component) and The main factors involved in the development of a more efficient relationship between OEMs and suppliers. To achieve this object, various activities were undertaken including the collecting of information from previous studies, preparing standardised questionnaires and performing investigations within the European car industry and also at a major automotive supplier. The work is based on empirical investigations and personal interviews conducted with key persons in automobile companies and automotive suppliers with the aim of painting a picture of the future situation and developing a proposal based on the information compiled. Finding answers to the above-mentioned issues may be very important and useful in determining internal organisational structure and resource allocation and in making strategic decisions in respect of alliances and collaborations when preparing one's own business for the even fiercer competition that will face automobile suppliers in the future.
140

Identification and multivariable feedback control of the vibration dynamics of an automobile suspension

Vanreusel, Stephen. January 2005 (has links)
This thesis considers the vibration control of an automobile suspension subject to road imperfections using multivariable feedback techniques. / Frequency-domain system identification methods are applied to model the dynamic behaviour of the suspension system from experimental test data using a data analysis software tool called CIFER. Advanced features such as the Chirp-Z Transform and composite window techniques are used to extract high quality frequency responses. A linear multivariable state-space model is derived which matches the experimental frequency response data set in the frequency range 65Hz-240Hz. / Accurate uncertainty modeling on the nominal suspension is needed to design controllers achieving acceptable levels of robustness and performance. It is shown that modeling errors are best characterized using a combination of both additive and multiplicative uncertainty, as well as perturbations of the state-space model parameters. / Robust feedback control design techniques using H-infinity and mu-synthesis are presented. It is shown both through simulation and experiment that vibration attenuation over the frequency range 65Hz-120Hz is achieved without affecting the system dynamic behaviour outside this range.

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