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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.
361

An explorative study of knowledge transfer processes in new product development in the automotive industry

Engel, Rupert January 2004 (has links)
This research builds on three projects that aim to investigate how knowledge transfer takes place in new product development in the automotive industry. The study seeks to picture how product development teams frame and shape new product knowledge, how they interpret such knowledge, and how they apply knowledge to the product development process. From that perspective, product development activities can be seen as transactions that are integrated into an overall system of identifying, assessing, collecting and combining knowledge. Results of my research so far reveal that there are many factors that affect the successful management of knowledge transfer in new product development projects. Based on my first two projects, using the case study approach, it is evident that for successful knowledge transfer to occur, there is a need to distinguish between design knowledge that is embedded in the tacit knowledge domain and that embedded in the or explicit design knowledge domain. The results of project three, using a survey questionnaire approach, provide a powerful demonstration, that knowledge integration, combination and creation in product development need intensive interaction and collaboration. The enormous importance of interaction and collaboration to integrate and combine knowledge has its origin in the nature of design knowledge. For example engineers produced in the survey a 82 % rate of agreement with the statement that they use mainly knowledge that comes from their past work experience as product developers, in order to solve complex design tasks. The underlying assumption of this finding is, that engineers are therefore mostly forced to transfer tacit design knowledge to solve complex design tasks. The research showed that a remarkable under-performance exists in knowledge identification and knowledge articulation in new product development in the automotive industry. In vehicle development, non-routine tasks are highly complex. This requires team members to have an understanding of the complete product system architecture. To create such an understanding, engineers need to identify and articulate knowledge. These activities can be seen as a pre-knowledge creation. The result is a shared product knowledge base, which makes it possible for people engaged in the vehicle development process to use different kinds of knowledge to capture and link new technologies into innovative products. This may require a cultural shift by vehicle manufacturers in terms of how they steer and allocate resources to future vehicle development programmes. Building on four years engagement with knowledge transfer research, I conclude that organisations in the automotive sector still rely on methods and processes that were successful in the past and strictly directed at exploiting tangible assets. To integrate preknowledge creation, as a new found discipline in product development projects creates an enormous potential to integrate and combine knowledge in an efficient way for future product development projects.
362

Véhicules électriques hybrides rechargeables : évaluation des impacts sur le réseau électrique et stratégies optimales de recharge / Plug-in hybrid electric vehicles : assessment of impacts on the electric grid and optimal charging strategies

Türker, Harun 20 December 2012 (has links)
Les engagements étatiques relatifs au secteur du transport promouvoient lapopularisation des véhicules rechargeables conformément aux exigences actuelles qu’ellessoient environnementales, techniques ou encore économiques. Ipso facto, ces travaux dethèse, assimilés à la thématique des Smart Grids, exposent une contribution à une gestionorientée du tryptique réseaux électriques, véhicules rechargeables et secteurs résidentiels.La première étape du travail consiste en l’évaluation des impacts liés à un taux de pénétrationélevé. Les travaux se sont ensuite focalisés sur deux problèmes importants qui sont latenue du plan de tension et le vieillissement accéléré des transformateurs de distributionHTA/BT, plus particulièrement ceux alimentant des secteurs résidentiels. Partant, desstratégies de modulation de la charge des batteries embarquées sont proposées et évaluées.Dans une seconde partie, en se basant sur l’hypothèse de bidirectionnalité énergétique duvéhicule électrique hybride rechargeable (Plug-in Hybrid Electric Vehicle - PHEV), estexploré les possibilités d’effacement de pointe et de diminution des puissances souscrites ;conformément au concept Vehicle-to-Home. Les aspects économiques ne sont pas évacués ;à ce titre la minimisation de la facture énergétique d’un logement fait l’objet d’un regardparticulier sous contrainte d’une tarification variable, le V2H servant de levier. Le véhiculebidirectionnel est enfin mis à contribution via une algorithmique adaptée à des fins deréglage du plan de tension et contribue ainsi au concept Vehicle-to-Grid. / The national commitments concerning terrestrial transport are promotingrechargeable vehicles according to actual environmental, technical or economicexigencies. To this end, the contribution of this thesis, related to the Smart Grids, coverssimultaneously the fields of electric utility grids, rechargeable vehicles, and residentialareas. The first step consists in the assessment the impacts caused by a highpenetration level. The research then focuses on two major problems : the voltage plan andthe aging rate of low voltage transformer, particularly those supplying residential areas.Therefore, unidirectional Plug-in Hybrid Electric Vehicles (PHEVs) charging strategieshave been proposed and evaluated. In the second part, based on the bidirectional PHEV,the possibility of consumption peak shaving and decrease of subscription contracts bothunder the concept Vehicle-to-Home are explored. The economics aspects are notignored, so a particular attention is paid of energy cost minimization for a housing undervariable pricing of energy constraint. The bidirectional vehicle is finally used in an adaptedalgorithmic for voltage plan control, thus contributing to the concept Vehicle-to-Grid.
363

Fast-response FID measurement of SI engine residual gas hydrocarbon concentration

Summers, Tim January 1996 (has links)
No description available.
364

Energy management system for the diagnosis and control of an automatic guided vehicle

Church, Stuart Michael January 2016 (has links)
With the increase in electronic equipment implemented in various systems, as well as the increase in calculating power that these devices offer, designers are being empowered to make use of this power in real-time systems to diagnose and protect the systems themselves. This reasoning is too compounded by the focus on efficiency and safety in the design of complex systems, as well as the increasing expense and sensitivity of the electronic components themselves. With this in mind, this dissertation aims at developing a comprehensive measurement, control and reaction system for the electrical diagnosis and ultimately optimisation of complex electrical and electronic systems. This system will serve as a real-time diagnosis tool, which will enable the real-time diagnosis of various components in an electro-mechanical system, which can then be interpreted to determine the working state of the various components. Another sphere of this project will involve the accurate monitoring of the battery status as well as actively balancing the series connected batteries. The focus on the batteries will seek to prolong the life of the batteries, while being able to squeeze as much capacity out of them. The initial design and testing will be based on an AGV system implemented at VWSA, however a main goal throughout the design process will be modularity, i.e. the ease of implementation of this system in other systems. The key technologies used in the development of this system will still comprise of the components used in the original AGV, however new prototype components sourced from Microcare are used for the battery management system, while current sensors directly connected to the PLC’s analog input ports will be used for the active monitoring of currents distributed through the AGV.
365

Air quality impact assessment of transport-related air pollutants

Clark, Alistair I. W. January 1984 (has links)
No description available.
366

Technological Fundamentalism? The Use of Unmanned Aerial Vehicles in the Conduct of War

Futrell, Doris J. 29 December 2004 (has links)
There is an on-going battle in the Department of Defense between reason and the faith in technology. Those ascribing to technological fundamentalism are blind to the empirical evidence that their faith in technology is obscuring the technological limitations that are evident. The desire for information dominance to reach the state of total transparency of the opponent in order to win the war is untenable. The reasoning voiced by skeptics should be heeded but the technological fundamentalists are deaf to their views. The use of UAVs have provided for limited visibility of the opponent and not the perfect Panopticon as envisioned. / Master of Public and International Affairs
367

Kinematics, Dynamics and Control of Single-Axle, Two-Wheel Vehicles (Biplanar Bicycles)

Abbott, Michael Shawn 20 April 2000 (has links)
A two-wheeled, single-axle, differentially driven vehicle possesses many salient advantages when compared to traditional vehicle designs. In particular, high traction factor, zero turn radius, and inherent static and dynamic stability are characteristics of this configuration. Drive torque is provided via a swinging reaction mass hanging below the axle. While mechanically simple, the resulting nonlinear vehicle dynamics can be quite complex. Additional design challenges arise if non-pendulating platforms or hardware mounts are required. Ultimately, this vehicle class has great potential in autonomous robotic applications such as mine clearance, planetary exploration, and autonomous remote inspection. This thesis discusses the kinematic and dynamic analyses of this vehicle class and develops design tools including performance envelopes and control strategies. Further, it confronts the stable platform problem and provides one solution while suggesting alternative design concepts for other applications. / Master of Science
368

A Guidance Algorithm for Unmanned Surface Vehicle Exhibiting Sternward Motion

Du, Shu 11 November 2013 (has links)
We propose a new dynamically feasible trajectory generation algorithm that incorporates sternward motion for unmanned surface vehicles. This work is motivated by riverine applications where the operating environment is large and poorly known. We extend a navigation approach for forward path planning into a more versatile framework that includes safe and dynamically feasible backward trajectories. We pose the backward trajectory generation problem as a finite-horizon optimal control problem and transform it into a nonlinear programming problem by utilizing the direct shooting method. The nonlinear programming problem is solved using the Hooke-Jeeves numerical algorithm. We provide successful simulation and field-trial results that demonstrate the performance of backward path planning algorithm. / Master of Science
369

Traction Control for KTH Formula Student

Collin, Felix January 2020 (has links)
When accelerating, traction from the tyres is necessary to move the vehicle forward. If too much torque is applied to the wheels of the vehicle, the tyres will start to spin and thereby the traction will decrease. This can occur when the driver of the vehicle applies to much throttle, but can be controlled with a traction control system that prevent the tyres from spinning and keeps the tyres at maximum traction to increase acceleration. In Formula Student competitions, every tenths of a second gained is vital and a traction control could help the driver to find these tenths of a second during acceleration. The purpose of this bachelor thesis was to design a slip ratio based traction control for the KTH Formula Student car DeV17 with focus on the acceleration event from standing start. A problem with standing start is the launch of the acceleration which were investigated along with a PID-controller. The model was developed in MATLAB's SIMULINK and simulated with IPG CarMaker. Small improvements in acceleration time were seen with the PID-controller but the launch did not see any improvements.
370

Study of In-vehicle Technology for Increasing Motorcycle Conspicuity

Campbell, Benjamin Scott 07 May 2016 (has links)
This study was conducted to determine whether adding in-vehicle technology to vehicles resulted in increased driver awareness of motorcycles. The specific technology tested consisted of a warning light which illuminated on the vehicle’s instrument panel when the vehicle was near a motorcycle. The effect of motorcycle color on driver awareness was also explored. Participants were recruited to drive a highidelity driving simulator in a city environment. Eye-tracker data was collected and used to determine how much attention drivers paid to the motorcycles in the simulation. Results showed that the in-vehicle technology significantly increased driver awareness of motorcycles, but the color of the motorcycles had no impact on driver awareness.

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