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Sverigedemokraterna - en textanalys - en granskande analys av ett partis politiska texterPersson, Erik January 2008 (has links)
The purpose of this dissertation is to examine and present six different texts produced by the Sweden democrats. This examination focuses its attention on the content and the technique of the arguments present in the texts. In addition, the results will be put in relation to the steering documents for the Swedish school system. The aim is to observe common features regarding content and technique present in the texts. More specifi-cally, I will examine how the texts produced by the Sweden democrats pose a problem to the Swedish school system. In this particular study, data were collected through a selection which resulted in six different texts representative for the Sweden democrats. In addition, to display a broader picture of the party, the texts are written by different writers. Having carried out this particular study, certain conclusions can be drawn. To begin with, the texts are comprehensive and treat similar issues, namely anti-multiculturalism and condescension against the establishment. Secondly, there is a difference regarding content depending on the receiver of the text. Finally, there is a discrepancy between the content of the arguments in the analysed texts and the steering documents of the Swed-ish school system. This is particularly noticeable when it comes to multiculturalism and the treatment of foreign people. However, the results also show that there are some similarities regarding maintenance of the Swedish culture.
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Modeling Of Liquid Crystal Display And Photonic DevicesGe, Zhibing 01 January 2007 (has links)
Liquid crystal (LC) materials have been widely applied in electro-optical devices, among which display is the most successful playground and numerous new applications in photonic areas (such as laser beam steering devices) are also emerging. To well guide the device design for optimum performance, accurate modeling is of prior and practical importance. Generally, the modeling of LC devices includes two parts in sequence: accurate LC molecule deformation extraction under external electric fields and optical calculation thereafter for the corresponding electro-optical behaviors. In this dissertation, first, hybrid finite element method and finite difference method are developed to minimize the free energy of the LC systems. In this part of study, with computer-aided derivation, the full forms of the LC free energy equations without any simplification can be obtained. Besides, Galerkin's method and weak form technique are further introduced to successfully degrade the high order nonlinear derivative terms associated with the free energy equations into ones that can be treated by first order interpolation functions for high accuracy. The developed modeling methods for LC deformation are further employed to study display structures, such as 2D and 3D in-plane switching LC cells, and provides accurate results. Followed is the optical modeling using extended Jones matrix and beam propagation method to calculate the electro-optical performances of different devices, according to their amplitude modulation property or diffractive one. The developed methods are further taken to assist the understanding, development, and optimization of the display and photonic devices. For their application in the display area, sunlight readable transflective LCDs for mobile devices and the related optical films for wide viewing angle are developed and studied. New cell structure using vertically aligned liquid crystal mode is developed and studied to obtain a single cell gap, high light efficiency transflective LCD that can be driven by one gray scale control circuit for both transmissive and reflective modes. And employing an internal wire grid polarizer into a fringe field switching cell produces a single cell gap and wide viewing angle display with workable reflective mode under merely two linear polarizers. To solve the limited viewing angle of conventional circular polarizers, Poincare sphere as an effective tool is taken to trace and understand the polarization change of the incident light throughout the whole LC system. This study further guides the design of high performance circular polarizers that can consist of purely uniaxial plates or a combination of uniaxial and biaxial plates. The developed circular polarizers greatly enhance the viewing angle of transflective LCDs. Especially, the circular polarizer design using a biaxial film can even provide comparable wide viewing angle performance for the same vertically aligned cell as it is used between merely two linear polarizers, while using circular polarizers can greatly boost the display brightness. As for the beam steering device modeling, the developed LC deformation method is taken to accurately calculate the associated LC director distribution in the spatial light modulator, while beam propagation method and Fourier transformation technique are combined to calculate the near and far fields from such devices. The modeling helps to better understand the origins and formations of the disclinations associated with the fringe fields, which further result in reduced steering efficiency and output asymmetric polarizations between positive and negative diffractions. Optimization in both voltage profile and driving methods is conducted to well tune the LC deformation under strong fringe fields and improve the light efficiency.
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Design of full electric power steering with enhanced performance over that of hydraulic power-assisted steeringBaharom, Masri B., Hussain, Khalid, Day, Andrew J. January 2013 (has links)
No / This paper presents a method of designing a full electrical power steering system to replace a hydraulic power-assisted steering system with improved performance and benefits including energy saving, improved steering 'feel', simpler construction and environmental gain. The designed performance of the electrical power steering system represented an ideal hydraulic power-assisted steering power boost curve which was mathematically modelled to provide the required control characteristic for the electrical power steering system, including variation in the perceived power assistance with the vehicle's forward speed. A full electrical power steering system provides all the torque necessary to steer the wheels, and the steering feel is artificially generated by an electric 'feedback' motor which provides resistance to the driver's input. The performance of the electrical power steering system described in this paper was enhanced by manipulating the reactive torque to the driver's input at the steering wheel so that it depended upon the driving conditions. Full-vehicle software models were generated using ADAMS/car software based on an actual car fitted with hydraulic power-assisted steering and full electrical power steering. The simulation results from both models were compared, and it is concluded that the steering performances of both systems were similar but the steering feel of the full electrical power steering system could be tuned to provide improved feedback to the driver in use. The performance of the full electrical power steering system could be further improved with the introduction of a controller to manipulate the steering feel during undesired conditions.
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Effect of component stiffness and deformation on vehicle lateral drift during brakingMirza, N., Hussain, Khalid, Day, Andrew J., Klaps, J. January 2009 (has links)
This article presents a simulation study into effects of compliant (flexible) components
(such as the engine subframe and the lower control arm) and their deflections on the characteristics
of a vehicle experiencing steering drift during straight-line braking. The vehicle front and
rear suspension are modelled using multi-body dynamic analysis software. The front suspension
model represents theMacPherson strut design of the vehicle and includes a rack and pinion steering
system, brake system, engine subframe, and a powertrain unit. The model has been analysed
under two steering control methods: fixed and free control. Suspension characteristics and the
effect of deflections arising from the subframe and the lower control arm on these suspension
characteristics have been analysed.
The simulations confirmed that variation of component stiffness and interactions within components
give rise to side-to-side deflections that could affect lateral drift during braking. It is
concluded that side-to-side variation of suspension characteristics can have a detrimental effect
on lateral drift during braking and that compliant components whose stiffness varies from side
to side can cause different side-to-side deflections that can induce and influence variation in
suspension characteristics such as toe steer angle that can lead the vehicle during braking.
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The Effect of Temporal Pressure on Responsiveness and Gaze Patterns during a Dynamic, Gap Passability Navigation TaskAlt, Jeromy January 2022 (has links)
No description available.
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Effects of Rear Bumper Beam Deletion on the Perception of Steering Performance of Commercial VehiclesBanks, Alan J. January 2015 (has links)
In order to remain competitive in the marketplace, all motor vehicle
manufacturers face difficult decisions with regard to balancing cost vs. feature.
That is to say that the manufacturer must balance the cost of the product to the
customer to remain competitive whilst offering appropriate technology and
standard features required by that customer.
All motor manufacturers are therefore under pressure to keep costs of nonfeature
items to a minimum. One of the cost reductions items prevalent on most
vehicles is the deletion of the structural member that attaches the rear bumper,
known as the bumper beam (RBB), which is researched in this Thesis. This
generates average vehicle savings of $20 and, as this is invisible to the
customer, should enable the manufacturers to realise a significant saving or
allow this revenue to be spent on additional feature without loss of vehicle
function.
However, in nearly all cases, deletion of the rear bumper beam has the effect of
degrading the steering responses of the vehicle by 1 to 1½ rating points (out of
10), which is contrary to the premise of cost reductions; which is to ensure that
vehicle function is unaffected.
Initial analysis of vehicles with deleted rear bumper beams cannot show an
objective measurable difference in any vehicle behaviours with or without the beam fitted, and hence CAE studies using ADAMS models cannot verify the
effects of the bumper beam. It was necessary to employ unconventional
modelling and testing methods such as rigid body, flexible body model
techniques as well as experimental studies included driving robots and expert
driver appraisals.
The research demonstrated that vehicle modelling methods currently used,
cannot establish or predict the complete vehicle ride and handling status. A total
vehicle model approach should be used without separating the body CAE
model and vehicle dynamics ADAMS model into separate entities.
Furthermore, it was concluded that the determination to the effects of body
hysteresis rather than pure stiffness is of crucial importance and that the
steering attribute could be maintained with the deletion of the RBB analytically.
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On the Dynamic Analysis of a Standard and Self-Steering SemitrailersElmadany, Mohamed M. 06 1900 (has links)
No abstract is provided. / Thesis / Master of Engineering (MEngr) / Scope and contents: This thesis describes an analytical study of the dynamics of a tractor-semitrailer vehicle. Two mathematical models; an articulated vehicle with self steering semitrailer and an articulated vehicle with a standard semitrailer, are developed to describe the longitudinal, lateral, vertical, pitching, rolling and yawing motions of the vehicle on a rough road surface. The natural frequencies of and the damped eigenvalues for both models are calculated. The steady state response of the vehicle components to the sinusoidal input profile of varying frequencies is calculated and the response curves are computer plotted in each case. For the self-steering semitrailer, the effect of varying the spring stiffness at the fifth wheel is studied. The dynamic loads imparted to the pavement due to the dynamic action of the vehicle in response to road irregularities, are also calculated. A discussion of the conclusions drawn from the analysis is given.
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Steering system modal analysis / Modalanalys av styrsystemMilani, Silvia January 2023 (has links)
The vehicle manufacturing sector is constantly evolving, and corporations are fully aware of increased consumer expectations for both driver and passenger´s comfort. SCANIA CV AB, as one of the largest Swedish manufacturers of commercial vehicles, has put an emphasis on this area. To guarantee these high-quality standards, several tests are conducted daily. Within this framework, this project aims to gain a better understanding of the phenomena associated with steering wheel vibrations. This project has an experimental focus on recreating sensitive driving conditions and addressing the vibration transfer paths to the main user interface such as the steering wheel. As widely known, the main problems related to vibrations come from resonance excitations. The most obvious solution would be to simply avoid matching any system´s eigenmodes with external excitations. Considering broadband excitations such as bumpy roads or engine vibrations, it is very unlikely that none of the critical frequencies is triggered. A better and more realistic idea would be minimizing the effects of these resonances by structural optimization. However, to do so, the eigenmodes should first be addressed. For this purpose, this project focused on identifying the annoying frequencies triggered while recreating sensitive driving scenarios. These sensitive scenarios were identified by Scania as circumstances in which the steering wheel feel gets altered. Specifically, it was decided to focus on road-induced vibrations, wheel-induced vibrations and engine-induced vibrations. The main findings show that during these tests, some resonances are triggered and interesting features are captured on the steering wheel. / Fordonstillverkningssektorn växer ständigt och företag är fullt medvetna om ökade konsumentförväntningar på både förarens och passagerarnas komfort. SCANIA CV AB, som en av de största svenska tillverkarna av kommersiella fordon, har lagt vikt vid detta område. För att garantera dessa högkvalitativa standarder genomförs flera tester dagligen.Inom denna ram syftar detta projekt till att få en bättre förståelse för de fenomen som är förknippade med rattvibrationer. Detta projekt har ett experimentellt fokus på att återskapa känsliga körförhållanden och adressera vibrationsöverföringsvägarna till huvudanvändargränssnittet, såsom ratten. Som allmänt känt kommer de största problemen relaterade till vibrationer från resonansexcitationer. Den mest uppenbara lösningen skulle vara att helt enkelt undvika att matcha något systems egenmoder med externa excitationer. Med tanke på bredbandsexcitationer som gropiga vägar eller motorvibrationer är det mycket osannolikt att ingen av de kritiska frekvenserna utlöses. En bättre och mer realistisk idé skulle vara att minimera effekterna av dessa resonanser genom strukturell optimering. För att göra det bör egenmoden först behandlas. För detta ändamål fokuserade detta projekt på att identifiera de irriterande frekvenser som triggades samtidigt som känsliga körscenarier återskapades. Dessa känsliga scenarier identifierades av Scania som omständigheter där rattkänslan förändras. Specifikt beslutades att fokusera på väginducerade vibrationer, hjulinducerade vibrationer och motorinducerade vibrationer. Huvudfynden visar att under dessa tester triggas vissa resonanser och intressanta funktioner fångas på ratten.
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Evaluation of the utility and performance of an autonomous surface vehicle for mobile monitoring of waterborne biochemical agentsWolfe, Jessica Simmerman 10 December 2021 (has links)
Real-time water quality monitoring is crucial due to land utilization increases which can negatively impact aquatic ecosystems from surface water runoff. Conventional monitoring methodologies are laborious, expensive, and spatio-temporally limited. Autonomous surface vehicles (ASVs), equipped with sensors/instrumentation, serve as mobile sampling stations that reduce labor and enhance data resolution. However, ASV autopilot navigational accuracy is affected by environmental forces (wind, current, and waves) that can alter trajectories of planned paths and negatively affect spatio-temporal resolution of water quality data. This study demonstrated a commercially available solar powered ASV equipped with a multi-sensor payload ability to operate autonomously to accurately and repeatedly maintain established A-B line transects under varying environmental conditions, where lateral deviation from a planned linear route was measured and expressed as cross-track error (XTE). This work provides a framework for development of spatial/temporal resolution limitations of ASVs for real-time monitoring campaigns and future development of in-situ sampling technologies.
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Beam Switching of an Nd:YAG Laser Using Domain Engineered Prisms in Magnesium Oxide Doped Congruent Lithium NiobateEvans, Jonathan W. 12 August 2010 (has links)
No description available.
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