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Tyra, Paula Marie [Verfasser], Jürgen [Akademischer Betreuer] Floege, and Peter [Akademischer Betreuer] Boor. "Collagen expression in renal fibrosis / Paula Marie Tyra ; Jürgen Floege, Peter Boor." Aachen : Universitätsbibliothek der RWTH Aachen, 2021. http://d-nb.info/1240390912/34.
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Chute, Christopher. "Decoding Neural Circuits Modulating Behavioral Responses to Aversive Social Cues." Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-dissertations/496.
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Understanding how the human brain functions on a molecular and cellular level is nearly impossible with current technology and ethical considerations. Utilizing the small nematode, Caenorhabditis elegans, and its innate behavioral responses to olfactory social cues, we can begin to unravel the mechanisms underlying social behavior. This is made possible given that innate behaviors are crucial for survival, and therefore hardwired into the genome of organisms. This allows for genetic-level analysis of neural circuitries driving behavior. Studying the neuronal mechanisms underlying C. elegans’ behavioral responses to social cues will not only assist in our overall understanding of how the brain perceives stimuli to enact a behavioral response at the cellular and molecular level, but also our understanding as to how the nervous system properly integrates information to enact social behavioral responses: mis-integration and social abnormalities are commonalities seen in many neuropsychiatric disorders, and these studies will provide fruitful insights into the defects observed in these disorders. Lastly, by comparing the perception of several different types of social chemicals, we can further our understanding of neural coding strategies for the various behaviors crucial for survival. Chapter One of this thesis orients the reader to social, innate behavior, and the usefulness of C. elegans as a tool for understanding behavioral coding. Chapter Two explores and establishes the required components of a socially aversive pheromone, providing insight into signaling evolution and co-option of biological machineries. Chapter Three examines how multiple, competing stimuli are integrated to modulate behavioral output, furthering our understanding of molecular and cellular integration and decision making within the nervous system. Chapter Four highlights the importance of predator pressure, and provides insights into circuit strategies of redundant and promiscuous networks of threat detection. Lastly, Chapter Five considers the implications of these findings as a whole, in the perspective of evolutionary strategies leading to neuronal coding of different behavioral outputs. Taken together, this dissertation aimed to fill the void in our understanding of social behavior neural circuitries, and how integration governed at the molecular and cellular level of the nervous system affects those behaviors.
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Ström, Lehander Karin. "I Tyra Kleens fotspår : en studie över konstnärens tid i Rom och Paris 1892-1908." Thesis, Uppsala universitet, Konstvetenskapliga institutionen, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-355263.
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This thesis describes and analyzes the symbolist artist Tyra Kleen’s life as a student and professional artist in late 1900th- and early 2000th-century, using biography as methodology, in combination with Pierre Bourdieu’s theories on Cultural Fields, and Feministic theory. A few of her Symbolistic art works will be analyzed using Ragnar Josephson’s theories on the Making of Art. The years in between 1892 – 1908 are in focus of the thesis, when the artist mainly lived, studied and worked abroad; in Germany, Paris and Rome. Tyra Kleen (1874-1951) was born in Sweden, but lived for many years in Europe. She saw herself more as a European or a Cosmopolitan, than a Swedish person. She went to several art schools in Europe; in Dresden, Karlsruhe, Munich, Paris and Rome. She lived in Paris during the years of ”the fine de siècle”, and then moved to Rome where she lived and worked for almost ten years. During her years abroad, with influences from artists as Böcklin and Puvis de Chavannes, authors as Charles Boudelaire and Edgar Allan Poe, and from Theosophy, she picked up a continental Symbolistic style, that is unique, and is not to be found in any other Swedish artists’ styles. The thesis gives a new piece to the puzzle regarding Swedish late 1900th-early 2000th-century Art History.
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Anderson, Carisa Claudia. "Ultraviolet light mutagenesis of the tyrA gene in Escherichia coli produces T - G transversions at 5'-CT sites /." Available to subscribers only, 2005. http://proquest.umi.com/pqdweb?did=1083540061&sid=7&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Thesis (M.S.)--Southern Illinois University Carbondale, 2005."Department of Molecular Biology, Microbiology and Biochemisty." Includes bibliographical references (leaves 65-72). Also available online.
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Williams, Danielle E. "Black Public Creative Figures in the Neo-Racial Moment: An Analysis of Tyra Banks, Tyler Perry and Shonda Rhimes, 2005-2010." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/communication_diss/39.
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ABSTRACT
This dissertation examines how Tyra Banks, Shonda Rhimes, and Tyler Perry negotiate blackness in terms of racial representation both in their interactions with the press and public as well as in their final product. Banks, Rhimes, and Perry are among the few prominent African American executive producers working in an industry of inequality. Each is the creative figure behind a prominent prime-time television show. This project contributes to the discussion of race and representation in the field of television studies.
I argue there is a connection between how Banks, Rhimes, and Perry publicly discuss race and how these perspectives are encoded in America’s Next Top Model (Banks), Grey’s Anatomy (Rhimes), and House of Payne (Perry) from 2005-2010. These three are vital case studies because their shows offer a range of African American representations and extra-textual discourses about representations.
Chapter Two historically contextualizes the industrial shifts in mainstream broadcast networks and basic cable channels as it relates to blackness onscreen and diversity behind the scenes. ABC, The CW, and TBS are the focus of this chapter because they are the outlets for Banks, Rhimes, and Perry’s shows. I also position ABC, The CW, and TBS in relation to the rest of the industry as it has moved from the multi-channel transition to the post- network era. Chapter Three examines how Banks, Perry and Rhimes promote and publicize themselves as the key creative figure of their shows. This analysis places each individual in different sites of the burden of representation, which each handles differently. Chapter Four explores the connection between the role blackness plays in their image as public creative figure and how it is represented in their texts through a representational analysis of America’s Next Top Model, Grey’s Anatomy and House of Payne.
This dissertation advocates a neo-racial framework to examine blackness on television and behind the scenes. A neo-racial framework acknowledges that racial inequities continue to exist and the context surrounding these inequities needs to be examined. I conclude that the Banks, Rhimes, and Perry cases show that we are not in a post-racial society or in the post-network era.
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Schantz, Madeleine. "Gif mig ljus och frihet eller förinta mig : En tematisk undersökning av ljusets betydelse enligt symbolism och psykoanalys i Tyra Kleens En psykesaga." Thesis, Södertörns högskola, Estetik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-44003.
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This essay examines the possible meaning of light as a symbol according to Tyra Kleen. The illustrated prose poetic tale En psykesaga (1902) is packed with mythological and symbolist references, and it becomes clear from the first page of the saga that Kleen was truly a symbolist of her time. The story is a paraphrase of the myth of Cupid and the Psyche, but with a new independent agent. To investigate the meaning of light, the thesis studies contextual studies in relation to the symbolism of Facos and Lundberg, in order to get close to the meta poetry of En psykesaga. In addition, a dream theoretical perspective according to Freud's psychoanalysis has been applied for a further dimension of the possible meaning of light.
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Guibert, Sylvain. "Génétique de la coloration de la robe chez les bovins : contribution à l'étude du rôle des gènes de la famille tyrosinase." Limoges, 2004. http://aurore.unilim.fr/theses/nxfile/default/8aee8701-9466-4f36-87f5-83d9ac584aa1/blobholder:0/2004LIMO0008.pdf.
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These works belong to the research thematic related to the identification of specific molecular markers for each French cattle breeds. They consist in the study of the tyrosinase family genes and of the RAB38 gene. The cloning and the polymorphism study of the coding region of TYR, TYRP1, DCT, RAB38 genes show a very good conservation at the genomic and proteic levels with other species. No racial polymorphism correlated to a phenotype has been detected. However, the transcriptional study shows that highly variable expression levels could explain the coat color differences. Notably, a lack in TYRP1 expression seems to be characteristic of the e/e animals at the EXTENSION locus. These works also confirm the epistatic property of the SILVER allele specific to the Charolaise breed
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Smith, Katherine Ann. "Are C. elegans receptors useful targets for drug discovery : identification of genes encoding seven potential biogenic amine receptors in the parasitic nematode Brugia malayi and pharmacological comparison of tyramine receptor homologues from Caenorhabditis elegans (TYRA-2) and B. malayi (Bm4) /." Connect to Online Resource-OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1170202762.
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Salminen, Henry. "Parametrizing tyre wear using a brush tyre model." Thesis, KTH, Aerodynamik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-163716.
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Studying rubber wear is important because it can save money, minimize health and environmental issues related to the particles generated from tyre wear and reduce fuel consumption. The wear of rubber is considered to be the result of energy dissipation due to friction. There are many models that describe the dynamical behaviour of vehicles and tyre, but less e ort has been dedicated to consider the tyre wear in these models. The purpose of the thesis was to create an easy to understand and trend-accurate tyre wear model for implementation in a complete car model. The tyre wear in the thesis is determined to be the amount of rubber volume loss due to sliding per unit length that the tyre travels. A literature study was performed with the objective of gaining knowledge of tyre models and the a ecting parameters of tyre wear. The most important parameters in determining tyre wear were identied as the forward velocity, side-slip angle, longitudinal slip, vertical load, and tyre ination pressure. The wear was chosen to be calculated with Archards wear law for these parameters both separately and combined in pairs in order to obtain a deeper understanding of the wear. The results show that wear is increasing exponentially for the forward velocity. Tyre wear decreases linearly as tyre ination pressure (vertical bristle sti ness) increases. The vertical load, longitudinal slip and side-slip angle yielded exponentially increasing wear. The most inuential parameters a ecting the tyre wear were the longitudinal slip and side-slip angle, these yielded wear rates up to 107 higher compared with the reference case. The developed tyre wear model is a good base for future work. More measurement data are needed in order to validate the model. For future work it is also recommended to implement camber angle and temperature dependency in order to study these two important parameters inuence on tyre wear.
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O'Boy, Daniel John. "Tyre/road noise : vibration of the tyre belt." Thesis, University of Cambridge, 2005. https://www.repository.cam.ac.uk/handle/1810/251965.
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Kubba, Ammar Issam Salih. "Intelligent tyre technologies." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8363/.
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This thesis reports an investigation about range of intelligent tyre technologies. A piezoelectric transducer was utilized to measure tyre inner liner strain in the longitudinal direction. Tyre driving condition can be recognized from different tyre strain pattern data which is collected from the piezoelectric transducers. Tyre load, slip angle, and rolling speed can be identified from the tyre strain pattern throughout the tyre contact patch area strain pattern. A novel circumferential four-chamber tyre concept was designed, manufactured and tested in this study. These four-chamber prototypes can have independent inflation pressure in each chamber to provide wide range of tyre behavior which is suitable for different road surfaces and driving conditions. The multi-chamber tyre has a range of modes to accommodate urban and motorway driving for rolling resistance and grip control. A multi-chamber tyre finite element model using ABAQUS software was developed from a conventional tyre model to design and validate these tyre prototypes. These multi-chamber tyre prototypes were manufactured with the assistance of Fusion Innovations Ltd and tested in the University of Birmingham tyre test rig. Finally, a shape memory alloy valve design was investigated to control the air flow in the multi-chamber tyre.
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Lamy, Christophe. "Novel accurate tyre slip angle measurement means : application to tyre model identification." Thesis, Mulhouse, 2010. http://www.theses.fr/2010MULH3256.
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Le trafic routier devenant de plus en plus dense, la sécurité active des véhicules doit être sans cesse améliorée. Ceci nécessite notamment une amélioration de la dynamique des véhicules. La majeure partie des efforts transmis par la chaussée au véhicule passant par les pneumatiques, une connaissance précise de l’interface pneu-sol est primordiale. Ceci passe notamment par le développement de modèles de pneumatiques et leur identification, à partir de mesures spécifiques, lors des phases de conception et de mise au point d’un véhicule. Le projet de thèse a pour objectif principal de contribuer à une meilleure détermination du point de fonctionnement dynamique de l’ensemble pneumatique/roue. Plus précisément, il s’agit d’améliorer la détermination de l’angle de dérive du pneumatique, dont la précision est encore aujourd’hui insuffisante pour une analyse des performances des pneumatiques à partir d’essais sur piste. Cette détermination est réalisée simultanément à la détermination des autres grandeurs nécessaires à l’étude de l’interface roue-sol : glissement longitudinal du pneumatique, angle de carrossage de la roue et torseur des efforts roue-sol. Ce projet s’est appuyé sur la collaboration entre la Direction de la Recherche de Renault et le laboratoire MIPS de l’Université de Haute-Alsace. Des études préliminaires menées par Renault et par le MIPS sur ce sujet ont servi de support à ce projet.Une étude menée en début de thèse a permis de rédiger un cahier des charges exhaustif, en termes de performances de mesure de l’angle de dérive du pneumatique, permettant d’étudier avec suffisamment de précision la dynamique du véhicule, en se basant sur indicateurs de performance. Afin de répondre au cahier des charges, une solution de mesure novatrice de l’angle de dérive du pneu a été conçue et développée au cours de la thèse. Celle-ci se base sur l’intégration de mesures inertielles et GPS au niveau du plan de jante, à l’aide d’un filtre de Kalman étendu (EKF). Par la suite, un capteur de mesure (INS/GPS) dédié a été conçu, développé et enfin intégré à un véhicule d’essais. Les performances de mesure du nouveau capteur INS/GPS ont été validées vis-à-vis du cahier des charges, en suivant une procédure de caractérisation mise au point spécifiquement durant la thèse. L’angle de dérive pneu est ainsi mesuré avec une précision de 0,1° (à 3o) sur une plage de 360°, tout en étant insensible à la texture et à la granularité de la chaussée ; contrairement aux solutions industrielles existantes. Lorsque ce moyen de mesure novateur est couplé à d’autres mesures standard de la dynamique du véhicule, le mouvement complet du plan de jante est alors déterminé également avec la précision requise. Ceci en ajoutant uniquement un capteur au niveau du plan de jante, ce qui permet de limiter l’inertie ajoutée à la roue, en comparaison aux moyens de mesures existants.Pour valider le nouveau moyen de mesure développé et montrer tout son intérêt, une méthodologie d’identification d’un modèle de pneumatique (Magic Formula 5.2) a été proposée et validée expérimentalement. Un algorithme d’optimisation Simplex a été développé afin de pouvoir identifier un modèle de pneu, aussi bien à partir de mesures (sur piste ou sur banc de test) qu’à partir de données de simulation. Ainsi, les paramètres du modèle de pneumatique peuvent être optimisés durant la phase de conception d’un véhicule, afin de répondre à des indicateurs de performance du véhicule bien définis. Aujourd’hui, les mesures précises du capteur INS/GPS, conjuguées à l’algorithme d’optimisation développé, sont notamment utilisées pour identifier des modèles de pneu à partir de mesure sur piste, et pour définir les paramètres du modèle de pneu nécessaires, en phase de conception de véhicule. […]The road traffic becomes more and more dense so that the active safety of road vehicles must continuously improved. This especially requires the improvement of the vehicle dynamics. The major part of the forces applied by the road to the vehicle are issued of the tyres. So, an accurate knowledge of the tyre-road interaction is primordial. This especially requires the development of the modelling and the identification of tyre models in the phases of design and tuning of a vehicle. The main goal of the thesis project is the contribution to a better determination of the dynamic functioning point of the system tyre/wheel. More accurately, is aims at improving the tyre slip angle determination accuracy, which is still insufficient for the analysis of tyre performance from vehicle-on-track tests. This determination is performed simultaneously to the determination of the other variables required in study of the tyre-road interface: longitudinal slip ratio, camber angle, tyre forces and moments. This project has been made in collaboration with the Research Department of Renault and the MIPS laboratory of the University of Haute-Alsace. Preliminary studies carried out by Renault and MIPS on this topic have served as a support to this project. A study carried out at the beginning of the thesis has helped to the determination of exhaustive requirements, in terms of tyre slip angle measurement performance, allowing the study of the vehicle dynamics with a sufficient accuracy, using performance indicators. A novel tyre slip angle measurement means has been developed in the thesis, in order to fit these requirements. It is based on the combination of inertial and GPS data near the wheel rim edge plane, using a extended Kalman filter (EKF). A dedicated measurement sensor (INS/GPS) has then be designed, developed and embedded in a test vehicle. The measurement performance of the novel INS/GPS has been validated according to the requirements, following a characterization procedure which has been specifically designed in the thesis. The tyre slip angle is then measured with an accuracy of 0.1° (at 3σ) in a range of 360°, with a insensitivity to the texture and the granularity of the road, contrary to the existing industrial solutions. When this novel measurement means is coupled with other standard measurements in vehicle dynamics, the whole motion of the wheel rim is then also determined with the required accuracy. This is made possible by mounting only one sensor at the level of the wheel rim edge plan, which helps to limit the inertia added to the wheel, in comparison with the existing measuring systems.A strategy of identification of a tyre model (Magic Formula 5.2) has been proposed and validated experimentally, in order to validate the novel measurement means developed. A Simplex optimization algorithm has been developed for the identification of a tyre model, from measurements (on a track or on a test rig) and/or simulation data. So, the tyre model parameters can be optimized in the phase of vehicle design, in order to fit well know vehicle performance indicators. The accurate INS/GPS measurements, combined with the optimization algorithm, are now especially used for the identification of tyre models from vehicle-on-track measurements and for the determination of the tyre model parameters required in the design phase. The novel INS/GPS is also considered as a reference for the tyre slip angle measurement, whatever the road grip (dry, wet, snow covered, ice covered ...). A number of research collaborations, especially with a worldwide tyre manufacturer, are been launched following the thesis results, especially for the study of the correlation between the physical tyre properties and the vehicle dynamics
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Tsinias, Vasileios. "A hybrid approach to tyre modelling based on modal testing and non-linear tyre-wheel motion." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/17852.
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The current state-of-the-art tyre models tend to be demanding in parameterisation terms, typically requiring extensive and expensive testing, and computational power. Consequently, an alternative parameterisation approach, which also allows for the separation of model fidelity from computational demand, is essential. Based on the above, a tyre model is introduced in this work. Tyre motion is separated into two components, the first being the non-linear global motion of the tyre as a rigid body and the second being the linear local deformation of each node. The resulting system of differential equations of motion consists of a reduced number of equations, depending on the number of rigid and elastic modes considered rather than the degrees of freedom. These equations are populated by the eigenvectors and the eigenvalues of the elastic tyre modes, the eigenvectors corresponding to the rigid tyre modes and the inertia properties of the tyre. The contact sub-model consists of bristles attached to each belt node. Shear forces generated in the contact area are calculated by a distributed LuGre friction model while vertical tread dynamics are obtained by the vertical motion of the contact nodes and the corresponding bristle stiffness and damping characteristics. To populate the abovementioned system of differential equations, the modal properties of the rigid and the elastic belt modes are required. In the context of the present work, rigid belt modes are calculated analytically, while in-plane and out-of-plane elastic belt modes are identified experimentally by performing modal testing on the physical tyre. To this end, the eigenvalue of any particular mode is obtained by fitting a rational fraction polynomial expression to frequency response data surrounding that mode. The eigenvector calculation requires a different approach as typically modes located in the vicinity of the examined mode have an effect on the apparent residue. Consequently, an alternative method has been developed which takes into account the out-of-band modes leading to identified residues representing only the modes of interest. The validation of the proposed modelling approach is performed by comparing simulation results to experimental data and trends found in the literature. In terms of vertical stiffness, correlation with experimental data is achieved for a limited vertical load range, due to the nature of the identified modal properties. Moreover, the tyre model response to transient lateral slip is investigated for a range of longitudinal speeds and vertical loads, and the resulting relaxation length trends are compared with the relevant literature.
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Ersanilli, V. "Automotive tyre fault detection." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/77d0e8a8-9b9d-4535-b961-cab355f7e3ff/1.
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The focus of the work in this thesis is concerned with the investigation and development of indirect measurement techniques. The methodology adopted is a combination of practical experimental, analytical deductive reasoning and simulation studies. This has led to proposals for a number of indirect tyre pressure monitoring systems, which are able to detect pressure loss under specific circumstances. The outcome overall is a proposal for a new supervisory system comprising of a modular framework, allowing various algorithms and techniques to be implemented in a complementary manner as they emerge and data sources become available. A number of contributions to the field have been made, which to the knowledge of the author, provide potential for further algorithm development and are imminently applicable given the above. The methods include a tyre pressure diagnosis via a wheel angular velocity comparator, the development of a model-based tyre pressure diagnosis via application of an unknown input observer and a parameter estimation scheme, a model-based tyre pressure diagnosis approach via an enhanced Kalman filter configured to estimate states including the input, a model-based tyre pressure diagnosis via cautious least squares, an investigation and critique of the effects of the choice of sampling interval on discrete-time models and estimation thereof. It is considered, that the extensive literature review provides a valuable historic insight into the tyre fault detection problem. It is clear, from the development and testing of the algorithms (and also the literature), that no single indirect pressure detection method is able to reliably detect changes in all driving scenarios which the regulations typically stipulate (depending on jurisdiction). In the absence of any information about the road input, the majority of the detection work must be shouldered by the wheel angular velocity comparator algorithm. As image recognition and sensor technology develops, it becomes possible to make estimates about the road surface and this removes some of the uncertainty on the input of the model-based parameter estimation approaches. Further work is detailed which goes some way towards realising the next steps in a development cycle suitable for a vehicle manufacturer to take through to the implementation stage.
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Graf, Regina Anna Gertrud. "Tyre-road interaction noise." Thesis, University of Cambridge, 2003. https://www.repository.cam.ac.uk/handle/1810/251876.
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Bécot, François-Xavier Guyader Jean-Louis Kropp Wolfgang. "Tyre noise over impedance surfaces." Villeurbanne : Doc'INSA, 2004. http://docinsa.insa-lyon.fr/these/2003/becot/index.html.
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Thèse doctorat : Acoustique : INSA LYON : 2003. Thèse doctorat : Acoustique : Chalmers University of Technology, Göteborg : 2003.Thèse soutenue en co-tutelle. Titre provenant de l'écran-titre. Le titre en français ne figure pas sur la page de titre. Bibliogr. p. 140-152.
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Lessing, Reed. "Interpreting discontinuity Isaiah's Tyre oracle /." Theological Research Exchange Network (TREN), 2001. http://www.tren.com.
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Lessing, R. Reed. "Interpreting discontinuity Isaiah's Tyre oracle /." Online full text .pdf document, available to Fuller patrons only, 2001.
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Caire, Emmanuèle. "Critias d'Athènes, sophiste et tyran." Aix-Marseille 1, 1998. http://www.theses.fr/1998AIX10009.
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De critias, fils de callaischros, nous est parvenue a travers les siecles une etrange image, aux facettes multiples et parfois contradictoires. Aristocrate esthete, poete et philosophe, critias qui fut le cousin de platon, le familier de socrate et l'eleve des sophistes, fut aussi, durant les huit derniers mois de son existence, le chef de la faction la plus dure des trente, et l'instigateur d'une oligarchie que lui- meme definissait, selon xenophon, comme une "tyrannie". Comme l'irruption tardive de critias dans la politique fut l'une des plus violentes et des plus radicales qu'ait connues l'histoire athenienne, comme les auteurs anciens trahissent un certain embarras pour l'expliquer, on pouvait se demander si l'oligarchie des trente marquait vraiment, dans l'existence de critias, une rupture brutale, due a des motivations personnelles, ou si elle s'inscrivait dans la continuite de l'elaboration d'une theorie politique. En interrogeant tour a tour les origines, la formation, la biographie et l'ensemble de l'oeuvre de critias, cette these se propose de retrouver une coherence entre les ecrits du "sophiste" et l'action du "tyran", qui ont ete si frequemment dissocies, voire meme opposes. L'origine des apparentes contradictions de critias doit etre recherchee dans la convergence de deux influences : celle de la tradition aristocratique athenienne et celle de la pensee des sophistes, qui se rejoignent chez lui en une reflexion originale sur la nature et la valeur des "constitutions" et surtout sur les conditions d'acquisition et d'exercice du pouvoir. Admirateur de l'oligarchie lacedemonienne, telle qu'il en avait, dans son oeuvre, redessine les traits, nostalgique d'une societe aristocratique idealisee, critias aurait pu inventer l'utopie politique. En entreprenant de traduire l'utopie dans les faits, il se fit l'acteur et le theoricien d'une forme de regime ou l'ideologie se conjuguait avec le realisme le plus brutal pour eriger la terreur en methode de gouvernementCritias, son of callaischros, was remembered as a disconcerting and ambiguous figure. Aristocrat and aesthete, poet and philosopher, critias, the cousin of plato's mother, had consorted with socrates and had been a follower of the most famous sophists of his time. But, when he came into power in 403 b. C, he was, during the eight last months of his life, the leader of the extremists among the thirty, and he established the rule of a radical oligarchy explicitly definited by himself, according to xenophon, as a "tyranny". Since critias' appearance into politics was one of the most radical and violent in athenian history, it may be wondered whether critias degeneration into a tyrant was the result of a change brought about by a desire of revenge on democracy, or the fruit of a theory elaborated, throughout his life, about political constitutions. The purpose of this work is to put forward the hypothesis that there is unity and coherence between the "sophist's" works, and the "tyrant's" conduct. The origin of critias' apparent contradictions is to be found in the convergence of the influences of aristocratic athenian tradition and of the sophists' theories, synthesized by critias in an original thinking over the nature of the best constitution and, above all, over the ways and means to obtain and keep power. Admiring lacedaimonian organization of state and yearning over an idealized aristocratic society, critias could have imagined political utopia. But, attempting to carry utopia into effect, he became the chief actor and the theorizer of a rule where ideology was combined with the most brutal realism in such a manner that the reign of terror was made a system of government
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Tsotras, Achillefs. "On the interaction between modal behaviour and shear force behaviour of a pneumatic tyre." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6031.
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The in-plane phenomena of interaction between the tyre structural response and contact force generation are investigated in this work. The challenges of the physical tyre simulation are identified, primarily associated with the computational load imposed by the need to capture the space distributed mechanisms that prescribe the above interaction. The method of modal expansion and reduction is proposed for the moderation of this load. The theoretical framework for the transformation of a tyre modal representation into a transient contact and shear force generation model is developed. Various modelling approaches are examined with regards to their modal prediction characteristics. Linear and non linear structural features as well as the physical properties that define the broad range modal behaviour are identified. A discretised form of the ring model is derived and combined with a foundation of viscoelastic tread elements for simulating the transient contact behaviour of the tyre. The resulting pattern of the modes' excitation justifies the validity of the modal reduction method and reveals the relative importance of various mechanisms and physical properties in tyre contact behaviour. The interaction between the friction controlled shear slip of the tread, the belt compliance and the sidewall buckling is found to be reflected on the two-dimensional contact pressure distribution patterns. A method able to simulate the dynamic transient rolling and slipping operating conditions is developed, although the small displacement assumption of the modal approach is dropped. The method, which is based on the combined modal-time and space-time domain solutions, is applied on the study of the physical mechanism of the launch process. The examination of the model under steady state kinematic conditions reveals the saturation of the traction force for profound levels of slip, which highlights the contribution of the structural mechanisms on the macroscopically observed shear force performance of the tyre. The variation of the modes' level of excitation, as induced by the operating conditions, is proposed for the capture of the physical properties effect on tyre behaviour and performance.
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Peckelsen, Ulrico [Verfasser]. "Objective Tyre Development : Definition and Analysis of Tyre Characteristics and Quantification of their Conflicts / Ulrico Peckelsen." Karlsruhe : KIT Scientific Publishing, 2017. http://www.ksp.kit.edu.
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Yang, Xiaoguang. "Finite element analysis and experimental investigation of tyre characteristics for developing strain-based intelligent tyre system." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/3072/.
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This thesis reports an investigation into the relationships between the tyre strain feature and tyre operating conditions based on finite element analysis and experiments for the development of a strain-based intelligent tyre system, which could estimate the tyre operating characteristics for optimising vehicle dynamics control and improving vehicle safety. A 175/505R13 tyre is adopted as the subject of this study. An efficient and effective material property determination procedure is developed for investigating the rubber and reinforcement material properties by experiment. Considering the possibility of the absence of tyre composite profile due to proprietary protection by tyre manufacturer, a novel imagebased method is developed to capture the tyre geometry feature from the tyre product cut cross-section. Both the 2D and 3D finite element tyre models are created in the commercial finite element code ABAQUS. The generated finite element tyre models are validated with experimental data and then adopted to construct the comprehensive relationship between tyre strain feature and tyre operating characteristics. Experimental validation of these estimation models are implemented based on a custom designed test system. Finally, some recommendations are presented for improving the capability of the finite element tyre model and the strain-based intelligent tyre test system.
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Promputthangkoon, Panu. "Liquefaction of Sand-Tyre Chip Mixtures." Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515469.
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Lee, King Lung. "Design of waste tyre pyrolysis process /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CBME%202009%20LEEK.
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Carvalho, Andrea Marques de. "O auxiliar aspectual Tyka do Karitiana." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/8/8139/tde-25082010-144136/.
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Este trabalho investiga a semântica da palavra tyka do Karitiana, língua amazônica da família Arikém do tronco Tupi falada atualmente por cerca de 320 pessoas em uma reserva localizada em Porto Velho, Rondônia (Nelson Karitiana - com. pessoal - 2005).This research investigates the semantics of the word tyka in Karitiana, an Amazonian language of the Arikém family (Tupi stock) spoken nowadays by approximately 320 people who live in their own reservation located in Porto Velho, Rondônia (Nelson Karitiana - personal communication - 2005).
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Grip, Marcus. "Tyre Performance Estimation during Normal Driving." Thesis, Linköpings universitet, Fordonssystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176558.
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Driving with tyres not appropriate for the actual conditions can not only lead to accidents related to the tyres, but also cause detrimental effects on the environment via emission of rubber particles if the driving conditions are causing an unexpectedly high amount of tread wear. Estimating tyre performance in an online setting is therefore of interest, and the feasibility to estimate friction performance, velocity performance, and tread wear utilizing available information from the automotive grade sensors is investigated in this thesis. For the friction performance, a trend analysis is performed to investigate the correlation between tyre stiffness and friction potential. Given that there is a correlation, a model is derived based on the trend having a stiffness parameter as an input in order to predict the friction performance. Tendencies for a linear trend is shown, and a linear regression model is fitted to data and is evaluated by calculating a model fit and studying the residuals. Having a model fit of $80\%$, the precision of the expected values stemming from the proposed model is concluded to be fairly low, but still enough to roughly indicate the friction performance in winter conditions. A tread wear model that can estimate the amount of abrasive wear is also derived, and the proposed model only utilizes available information from the automotive grade sensors. Due to the model having a parameter that is assumed to be highly tyre specific, only a relative wear difference can be calculated. The model is evaluated in a simulation environment by its ability to indicate if a tyre is under the influence of a higher wear caused by a higher ambient temperature. The results indicates that the model is insufficient in an online setting and cannot accurately describe the phenomena of softer tyres having a larger amount of wear caused by a high ambient temperature compared to stiffer tyres. Lastly, a double lane change test (ISO 3888-2) is conducted to determine the critical velocity for cornering manoeuvres, which defines the velocity performance. The test was executed for six different sets of tyres, two of each type (winter, all-season, and summer). The approach to estimate the velocity performance in an online setting is analogue to that of the friction performance, and a trend analysis is performed to investigate the correlation between longitudinal tyre stiffness and the critical velocity. The results are rather unexpected and shows no substantial differences in velocity performance, even though the tyre-road grip felt distinctively worse for the softer tyres according to the driver. It is concluded that the bias stemming from the professional driver's skills might have distorted the results, and that another approach might need to be considered in order to estimate this performance.
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Jabali, Aghyad, and Husein Abdelkadir Mohammedbrhan. "Tyre sound classification with machine learning." Thesis, Högskolan i Gävle, Datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36209.
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Having enough data about the usage of tyre types on the road can lead to a better understanding of the consequences of studded tyres on the environment. This paper is focused on training and testing a machine learning model which can be further integrated into a larger system for automation of the data collection process. Different machine learning algorithms, namely CNN, SVM, and Random Forest, were compared in this experiment. The method used in this paper is an empirical method. First, sound data for studded and none-studded tyres was collected from three different locations in the city of Gävle/Sweden. A total of 760 Mel spectrograms from both classes was generated to train and test a well-known CNN model (AlexNet) on MATLAB. Sound features for both classes were extracted using JAudio to train and test models that use SVM and Random Forest classifi-ers on Weka. Unnecessary features were removed one by one from the list of features to improve the performance of the classifiers. The result shows that CNN achieved accuracy of 84%, SVM has the best performance both with and without removing some audio features (i.e 94% and 92%, respectively), while Random Forest has 89 % accuracy. The test data is comprised of 51% of the studded class and 49% of the none-studded class and the result of the SVM model has achieved more than 94 %. Therefore, it can be considered as an acceptable result that can be used in practice.
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Daouti, Panagiota. "Homère et Platon chez Maxime de Tyr." Thesis, Montpellier 3, 2015. http://www.theses.fr/2015MON30042.
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Le retour à la littérature classique et l'héritage culturel sont omniprésents dans les œuvres littéraires, rhétoriques ou philosophiques de l'époque de Maxime de Tyr. Maxime suit cette tradition puisque dans ses Dialexeis sont éparpillées des références aux auteurs qui le précèdent. Maxime est influencé surtout par Homère et Platon comme on constate en lisant ses Dialexeis, où il montre sa prédilection pour les deux grands maîtres. Quant à Homère on trouve des citations utilisées pour illustrer ou pour compléter le sens d'un ensemble des phrases du texte de Maxime. Quelquefois Maxime procède à un léger changement dans les vers homériques afin de les adapter à l'entité syntaxique de son propre texte. Il y aussi des références aux noms ou aux épisodes pris dans les épopées homériques. Maxime utilise aussi l'allégorie homérique pour véhiculer des idées ou développer sa pensée philosophique.L'influence de Platon est profonde et s'étend à tous les domaines de la pensée de Maxime : politique, religieux, artistique, mais surtout philosophique. L'auteur des Dialexeis se trouve devant le problème épineux de la réconciliation de la philosophie avec la poésie. C'est en utilisant les citations des épopées homériques que Maxime trouve une manière de parler des conceptions philosophiques. Autrement dit, les exemples pris dans le texte d'Homère sont surtout utilisés afin que Maxime rende plus claire et explicite sa parole chaque fois qu'il expose ses idées philosophiques. Maxime prouve dans l'œuvre même, qu'un poète peut être aussi un grand philosophe, scellant ainsi la coexistence et arrivant à la réconciliation entre Homère et PlatonThe return to the classical literature and the evocation of cultural heritage are ubiquitous in the works of literature or those related to rhetoric and philosophy during the first centuries of the Roman Empire. Maximus of Tyr, who lived in the time of Commodus', follows this trend, as his Orations are full of citations or references to the works of his predecessors. However, he shows his preference for Homer and Plato, as their influence is evident in the Orations. As far as Homer is concerned, we mostly find citations that illustrate Maximus' text or complete the meaning of a series of phrases. Sometimes Maximus intervenes in Homer's text in order to adapt it to his own. Moreover, we can find references to names or to precise moments of the Iliad or the Odyssey, which are dispersed in the Orations. Maximus uses, also, the Homeric allegory in order to convey his thoughts about some philosophical issues such as the harmonious style of life, the pursuit of human felicity and the cultivation of a virtuous character. Plato's influence is also profound and it is extended to a wide range of Maximus' interests: politics, religion, art and mainly philosophy. Furthermore, in an effort to reconcile poetry and philosophy, Maximus uses the Homeric citations so as to develop more explicitly his philosophical conceptions, which, otherwise, would have stayed obscure. In this way he proves that a poet can be at the same time a great philosopher sealing the coexistence and bridging the differences between Homeric poetry and Platonic philosophy
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Scandaglia, Giulia. "Les Gesta Apollonii, un jalon du succès de l'Historia Apollonii regis Tyri au Moyen Age. Présentation et traduction française." Thesis, Paris 3, 2019. http://www.theses.fr/2019PA030071.
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Les Gesta Apollonii sont une réélaboration en 792 hexamètres léonins des huit premiers chapitres de l’Historia Apollonii regis Tyri, et ils ont été publiés par E. Dümmler pour les Monumenta Germaniae Historica, dans le deuxième volume de la section Poetae latini aevi Carolini en 1884. Comme l’œuvre dépend de son hypotexte, le premier chapitre de la thèse est dédié à l’Historia Apollonii regis Tyri, aux problèmes que ce roman soulève et aux réponses possibles que la critique leur a apportées. Une analyse du cadre historico-culturel dans lequel les Gesta Apollonii ont été composés et l’histoire du monastère où le manuscrit a été retrouvé ont été abordées dans le deuxième chapitre ; en outre, une partie importante de ce chapitre est consacrée à l’étude des gloses marginales et interlinéaires dont le texte est parsemé. Une partie de ces gloses a été trouvée dans un codex de De Consolatione Philosophiae de Boèce, rédigé vers l’an 1000 par l’abbé Froumund de Tegernsee, qui provient de la Fürstliche Öttingen-Wallersteinische Bibliothek, en Bavière et qui se trouve, aujourd’hui, à Cracovie, dans la Biblioteka Jagiellońska. Dans le troisième chapitre, plus spécifiquement, le texte des Gesta Apollonii est mis en parallèle avec le roman sur lequel il se fonde et avec les nombreuses références au monde classique grec et latin qu’il présente. Un sous-chapitre est de plus dédié à l’historicité possible des personnages mentionnés dans l’histoire.Après l’analyse du texte d’un point de vue thématique, le quatrième chapitre est dédié à l’examen des caractéristiques codicologiques et paléographiques du manuscrit et à la présentation de la langue, du style et de la métrique de l’œuvre. Le cinquième et dernier chapitre propose la traduction française de l’œuvreGesta Apolloni is a re-elaborated version of 792 leonine hexameters of the first 8 chapters of Historia Apollonii regis Tyri, and it was published in 1884 by E. Dümmler in Monumenta Germaniae Historica, in the second volume of the section Poetae latini aevi Carolini. Due to its dependence from its hypotext, the first chapter of the thesis is about Historia Apollonii regis Tyri, the issues that the novel raises, and the possible answers that the critics gave to them. A general analysis of the cultural and historical background where Gesta Apollonii was written and also the story of the monastery where it was found, have been discussed in the second chapter; moreover, an important part of this chapter is dedicated to the study of the marginal and interlinear glosses of which the text is full. Part of these glosses was found in a codex of Boece’s De Consolatione Philophiae, written circa 1000 by abbot Froumund De Tegernsee; originally the codex was in the Fürstliche Öttingen-Wallersteinische Bibliothek in Bavaria, today it can be found in the Biblioteka Jagiellońska, in Cracow.In the third chapter more specifically, Gesta Apollonii text is compared to the novel -which it is based on- and to the several quotes from the Latin and Greek classical world. A paragraph is also dedicated to the possible historical accuracy of the characters mentioned in the story. After the thematic analysis of the text, the fourth chapter concerns the examination of the codicological and paleographic features of the manuscript and the presentation of the language, the style, and the metre of the work. In the fifth and last chapter, there is a French translation of Gesta Apollonii
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He, Mingzhe, and Xinyu Lin. "Connected Tyres : Real-time Tyre Monitoring System for Fleet& Autonomous Vehicles with Tyre WearEstimation through Sensor Fusion." Thesis, KTH, Fordonsdynamik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290080.
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Tyres are one crucial part for vehicles, as they are the only contact pointbetween the vehicle and the road. Intelligent tyres are a trending new subjectin the tyre industry. They are designed to monitor various tyre states and sendthis information to both drivers and remote servers. The master thesis focuseson the proposal of a real-time tyre monitoring system for fleet and autonomousvehicles. It includes developing a tyre wear model and analysis of the currenttyre pressure monitoring functionality by leveraging the connectivity of fleetvehicles equipped with a Volvo web cloud service. The tyre wear model indirectlymonitors the tread depth of the vehicles all four tyres by identifyingcharacteristics between worn and fresh tyres. The two characteristics are identifiedby monitoring and analyzing vehicle speed and braking signals. The twocharacteristics is input to a voting scheme which decides when a worn tyre isdetected. The test vehicle was a Volvo XC40 with three types of tyres: wintertyres, summer tyres and worn summer tyres. The wear model gives 90 %accuracy to 10 set of test data, randomly selected from all dataset at HälleredProving Ground (Sweden). The connectivity realizes the data transmissionfrom the raw data of onCAN and FlexRay signals stored in a Volvo web cloudservice to the tyre monitoring fleet system. The signals are filtered and resampled,leaving the required signals of the tyre pressure monitor system andthe tyre wear model. Two signals, Calibration Status and iTPMS Status, areused to perform a statistical analysis on tyre pressure by categorizing the calibrationstatus and the tyre pressure conditions.The project outcome is an interfacebuilt on MATLAB GUI for demonstration of vehicle identification andtyre health conditions, with the embedded tyre wear model and connectivity.Däck är en viktig del för fordon, eftersom de är den enda kontaktpunktenmellan fordonet och vägen. Intelligenta däck är ett trendigt nytt ämne i däckindustrin.De är utformade för att övervaka olika däcktillstånd och skicka dennainformation till både förare och fjärrservrar. Examensarbetet är inriktat på ettförslag till ett däckövervakningssystem i realtid för fordonsflottor och autonomafordon och inkluderar en däckslitagesmodell och anslutning. Det inkluderaratt utveckla en slitagemodell och analys av den aktuella däcktrycksövervakningsfunktionengenom att studera Volvos fordonspark som är utrustade medVolvos webbmolntjänst. Däckens slitagemodell övervakar indirekt slitbanedjupetpå alla fyra däck genom att identifiera egenskaper mellan slitna och nyadäck. De två egenskaperna identifieras genom att övervaka och analysera fordonshastighet och bromssignaler. De två egenskaperna är inmatade i ett röstningsschemasom avgör när ett slitet däck upptäcks. Testfordonet var en VolvoXC40 med tre typer av däck, vinterdäck samt nya och slitna sommardäck.Modellen ger 90 % noggrannhet för 10 uppsättningar testdata, slumpmässigtvalda från alla dataset på Hällered provbana (Sverige). Anslutningen genomfördataöverföringen av rådata från onCAN och FlexRay-signaler lagrade ienVolvoswebbmolntjänst till däcksövervakningssystemet. Signalerna filtrerasoch samplas på nytt för att skapa de nödvändiga signalerna till däcktrycksövervakningssystemetoch däckslitagemodellen. Två signaler, kalibreringsstatusoch iTPMS-status, används för att utföra en statistisk analys av däcktrycketgenom att kategorisera kalibreringsstatus och däcktrycksförhållanden. Projektetsresultat är ett gränssnitt byggt på MATLAB GUI för demonstration avfordonsidentifiering och däcktillstånd. med inbäddad däckslitagemodell ochanslutning.
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Novodomský, Tomáš. "Měření radiální tuhosti pneumatik." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417520.
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This thesis deals with the radial stiffness of a tyre. The first part of is devoted to a brief description of a tyre construction. The next part is devoted to measuring the radial stiffness of a tyre and the design of a new measuring device. The last part of the thesis deals with the influence of the radial stiffness of a tyre on the vertical dynamics of ta vehicle and simulations of this effect in the MATLAB / Simulink software.
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Lee, Chiu-wing. "A critical review of waste tyre management /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B3473725X.
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王翠玲 and Cuiling Wang. "Study on the gasification of scrap tyre." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31241128.
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Lee, Chiu-wing, and 利超穎. "A critical review of waste tyre management." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B4501310X.
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Niderost, Kevin John. "Adhesion of steel tyre cord to rubber." Thesis, University of Birmingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314061.
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Wang, Cuiling. "Study on the gasification of scrap tyre /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22227039.
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Wang, Jiajun. "Measurement and identification of pneumatic tyre parameters." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/33663.
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This report deals with the measurement and identification of important parameters of various tyre models. Being a necessary step in the process of tyre related simulations, tyre testing is an important subject. In particular, making the test procedure simpler, more efficient and test results more accurate is what explored the most. For this project, after extensive studies on tyre modelling and testing, two problems were chosen to tackle. The first problem is tyre structural parameter identification being too difficult to carry out and time consuming, tyre modal testing in particular. The second problem is the usage of simple tyre models is limited due to they are normally parameterized on expensive professional tyre testing machines which are not commonly found in normal labs. In this study, it focuses on the identification of longitudinal relaxation length. In order to deal with the first problem, a convenient and effective approach of extracting tyre modal parameters is established. Compared with the conventional multi-degree curve fitting method, this new developed approach improves the efficiency and simplifies the curve fitting process dramatically while still maintaining adequate accuracy. In terms of solving the second problem, the development of a tyre relaxation length test is initiated. Virtual simulations using Matlab/Simulink have been carried out which has verified its principle. Feasibility, equipment design and the proposed test procedure of the practical test will also be discussed.
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Stallmann, M. J. (Martin Joachim). "Tyre model verification over off-road terrain." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/41012.
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Vehicle dynamic simulations form a significant part of the design and development process of vehicles. These simulations are used to study and improve the vehicle’s durability, ride comfort and handling capabilities. All forces acting on the vehicle are either generated in the tyre-road interface or are due to aerodynamic effects, where at low speeds the latter one can be ignored. The accuracy of the tyre model describing the forces on the tyre-road interface is thus of exceptional importance. It ensures that the simulation model is an accurate representation of the actual vehicle.
Various approaches are adopted when developing mathematical tyre models. Many of these models are developed to study the handling capabilities of passenger cars over a smooth road. Passenger car tyres are the focal point as larger tyres introduce some difficulties due to their size and load rating. Off-road truck tyres also differ in their construction which will influence force and moment generation of the tyre. Research efforts are increasing to meet the need of tyre models that can describe the behaviour of the tyre over uneven terrain with sufficient accuracy. This thesis addresses the question of whether existing mathematical tyre models can accurately describe the forces and moments generated by a large off-road tyre while driving over rough terrain.
The complexity of different mathematical tyre models varies greatly, as does the parameterisation efforts required to obtain the model parameters. The parameterization of most tyre models relies on some experimental test data that is used to extract the necessary information to fit model parameters. The selection of a suitable tyre model for a simulation is often dependent on the availability of such experimental data and the effort to identify the required parameters. In this study the parameterisation process for four different tyre models, are discussed in detail to highlight the difficulties in acquiring the test data and the effort to parameterize the model. The models considered are the One Point Contact, 3D Equivalent Volume contact, 3D Enveloping Contact and FTire model.
Experimental measurements are conducted on a 16.00R20 Michelin XZL tyre. Laboratory tests, as well as field tests, over discrete obstacles and uneven hard surfaces are used for parameterisation and validation purposes. Simulation results are compared to experimental test data to determine whether the models could be used to describe the tyre road interactions with sufficient accuracy. Recommendations are made for tyre model selection and model accuracy for simulations over rough off-road surfaces.Dissertation (MEng)--University of Pretoria, 2013.
gm2014
Mechanical and Aeronautical Engineering
unrestricted
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El-Razaz, Arafa Sayed Ahmed. "Lateral tyre forces on off-road surfaces." Thesis, University of Leeds, 1988. http://etheses.whiterose.ac.uk/227/.
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A successful model for off-road tyres must be reliable, efficient and capable of reproducing and predicting the main system phenomena. Mathematical models are proposed for longitudinal, lateral and combined lateral and longitudinal force generation characteristics of off-road tyres. For a better understanding of off-road tyre behaviour, the study of the interaction between the tyre forces and those generated by the deformed soil is very important. Details of the force system in the contact patch, therefore, are used as a basis for developing models for the prediction of the tractive performance and comering characteristics of off-road tyres. Previous work of the relevant literature pertaining to tyre behaviour is reviewed to provide the reader with background information on off-road tyre characteristics. Various models for off-road tyres of differing degrees of complexity but which all incorporate the key features of off-road tyre problems are then developed. Previous methods of analysing the combined lateral and longitudinal forces generated by off-road tyres on deformable surfaces are investigated. A modified version of a previous model is then proposed which is based on a different and original method for investigating tyre behaviour in the contact region. An entirely new model is then developed which is based on a modification of the "multi-spoke" tyre model used for road vehicle studies. Predicted results are compared with those obtained from other models and with reported experimental data. The usefulness of such models is in problems involving the steering, braking and handling behaviour of off-road vehicles. Hence, the models are formulated so that they can be applied to such vehicle problems by enabling lateral and longitudinal forces on the tyre to be predicted from any combined conditions of wheelslip, wheelskid and slip angle. The proposed models provide an improved qualitative description of behaviour in the contact region. Although slightly more complex than previous models, the computational load is nevertheless sufficiently small that the tyre models can conveniently be incorporated in off-road vehicle handling models. Suggestions for future recommendations are discussed with particular reference to improving the predictive models and for a possible extension of the study to generate more detailed practical results for tyre forces under controlled experimental conditions.
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Nazerian, Simon. "Kan strålar av ljus tyda det förflutna? : Användning av Reflectance Transformation Imaging (RTI) för att tyda runinskrifter på Pireus-lejonet." Thesis, Stockholms universitet, Arkeologiska forskningslaboratoriet, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-100721.
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This paper deals with testing the method Reflectance Transformation Imaging (RTI) on the copy of the Piraeus-lion in Historic Museum in Stockholm. The purpose is to find out if it is possible to gather more information about the runic inscriptions. RTI is a method that records the surface normal of individual pixels in a digital photograph by analyzing the impact of light coming from different angles of entrance. RTI produces sort of a 3D-image of the object. There will be an overview of earlier interpretations of the runic scripts written on the lion as well as an overview of Varangians in the southeast. After examination of the lion with RTI, has a conclusion been made that the method should be performed again on similar items, and on the copy of the Piraeus-lion to evaluate its full potential.
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Nilsson, Carl-Magnus. "Waveguide Finite Elements Applied on a Car Tyre." Doctoral thesis, KTH, Aeronautical and Vehicle Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3812.
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Structures acting as waveguides are quite common withexamples being, construction beams, fluid filled pipes, railsand extruded aluminium profiles. Curved structures like cartyres and pipe-bends may also be considered as waveguides. Wavesolutions in such structures may be found by a method calledthe Waveguide Finite Element Method or WFEM. This method uses afinite element approach on the cross-section of a waveguide tomodel the vibro-acoustic response as a set of linear, coupled,one dimensional, wave-equations.
In this thesis six novel waveguide finite elements arederived and validated. These elements are, straight and curvedpre-stressed, orthotropic or anisotropic shell elements,straight and curved fluid elements, and straight and curvedfluid-shell coupling elements.
Forced response and input power calculations for infiniteand periodic waveguides are presented. The assembled waveguidemodels can also serve as input for the Super Spectral FiniteElement Method, which enables forced response calculations formore complex boundaries. Furthermore, several properties ofdamped and undamped wave solutions are investigated.
Finally, a car tyre model, encompassing for the highlyanisotropic material and the air cavity inside the tyre is setforth. A number of forced response calculations for this modelare presented and compared with measurements with goodagreement.
Keywords:wave equation, wave solution, waveguide,finite element, spectral finite element, tyre noise, tyrevibration, input power, shells, pre-stress, fluid-shellcoupling axi-symmetric, two-and-half-dimensional
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Halim, Mahdi Hassan. "Truck tyre tread rubber : compounding and abrasion resistance." Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/6743.
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Jiao, Lejia. "Vehicle model for tyre-ground contact force evaluation." Thesis, KTH, Fordonsdynamik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177306.
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Economic development and growing integration process of world trade increases the demand for road transport. In 2008, the freight transportation by road in Sweden reached 42 million tonne-kilometers. Sweden has a tradition of long and heavy trucks combinations. Lots of larger vehicles, with a maximum length of 25.25 meters and weight of 60 tonnes, are used in national traffic. Heavier road transport and widely use of large vehicles contribute to the damages of pavement. According to a recent research by the VTI, total cost of road wear by freight transport in Sweden in 2005 was about 676 million SEK. If the weights of all vehicles were limited to 40 tonnes, according to the new EU rules, the cost of wear in 2005 would have been 140 million SEK less. Lots of studies about road damage caused by vehicle have been done since the last decades. It has been found that the dynamic tyre force plays an important role in the damages of pavement. However, the influence of vehicle-pavement interaction on pavement damage has not been investigated to any large extent yet. The aim of this study is to provide suitable computational truck models, study the influence of vehicle-pavement interaction and parameters of vehicle on pavement damage. To fulfil the aims, this study presents vehicle models, including quarter, half, full vehicle models and quarter vehicle model coupled with pavement, used to compute the dynamic tyre force. The different models are then compared. Two actual road profiles measured by laser, a smooth one and an uneven one, are used for evaluation. The models are analysed to find out the vehicle parameters that influence the road damage most and to learn about how detailed models are needed. It’s found that difference does exist between more detailed models and less detailed ones, and it’s non-negligible. It will increase with the increase of road unevenness. The dynamic tyre force will not be affected much by coupling the pavement, unless the road surface is very uneven or wheel hop exists. On uneven roads, energy mainly dissipates in vehicle suspension. However, on even roads, vibration can be well damped in tyre before it reaches suspension, so most of energy dissipates in tyre. Different components influence the tyre force differently. The influence varies with different frequency range of input signal (road profile) as well. The effects of sprung parts are mainly in low frequency range, while the effects of unsprung parts are mainly in high frequency range. Parameters of vehicle body influence the dynamic tyre force most. The effect of cabin is much smaller compared to vehicle body and unsprung part. Changes in parameters of pavement will not influence the road load, but its resonant frequency. Therefore, the best way to reduce dynamic tyre load is to design a more lightweight vehicle body, softer and better damped suspension.
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Handyside, Philip David. "The Old French translation of William of Tyre." Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/39389/.
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While the Latin version of William of Tyre’s chronicle of the Latin East, Historia rerum in partibus transmarinis gestarum, is a valuable tool for modern historians, it was not particularly well-known during the medieval period with only nine copies surviving. However, William’s history did become extremely popular through a translation of the original into Old French, the so-called L’Estoire de Eracles, with fifty-one surviving manuscripts. The Eracles text has been overlooked by scholars who have assumed that it is a simple translation of William’s text, and there has also been little work in to establishing a provenance for the translation or determining the translator’s motives. This thesis seeks to identify the extent to which the Eracles is a simple translation and assess its importance to historians. While, for the most part, the translator is faithful to William’s text, he made alterations throughout. Many are of a stylistic nature, and the translator did not simply abridge William’s text for a new audience. He made several additions that serve to identify him and his audience. In particular, he regularly added background material on French crusaders, and on events in France, including additional information not found in any other source. On occasion the translator alters William’s criticism of certain individuals and gives a very different version of events that may be more accurate. The major difficulty with studying the Eracles text is the fact that the nineteenth-century editions were reliant upon a limited number of manuscripts. There has been little work on these manuscripts and no clear understanding of the relationships between these manuscripts. This thesis also seeks to tackle this problem by presenting a critical edition of six sample chapters that takes into account all the surviving manuscripts and by establishing the relationships between these manuscripts.
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Lazarus, Linda Ruth. "The role of FIS in tyrT transcriptional regulation." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259766.
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Štiková, Adéla. "Hospodářský vývoj keltského tygra: problematika přímých zahraničních investic." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-85852.
Full textAbstract:
This diploma thesis deals with investment incentives and their effect on the economy of Ireland in historical and contemporary context. The introduction focuses on the general issue of foreign direct investment and investment incentives. After the summary of geographic and socioeconomic characteristics of the state the work describes an economic development of Ireland from 17 century to the present, especially the important historical events and their influence on the Irish economy. In the main part of this thesis, which is focused on the Irish investment incentives, are listed the general factors of the Irish economy in the form of so-called comparative advantages (high mobility and high skills of workforce, low labor costs) including specific benefits for U.S. investors (culture similarity, no language barrier, favorable geographic location, quality infrastructure) and economic and political measures in the field of direct investment, that Ireland has implemented to attract foreign investors (building of modern telecommunications infrastructure, the international experience of workforce and the establishing of organizations to promote foreign direct investment). Next the work analyses development of investment incentives from the beginning of their application in the 70th of the 20th century through the industrial "boom" in the 90th of the 20th century to the present, focusing on those of them that were key for the development of the Irish economy (taxes on income, efficient infrastructure, a flexible labor market, etc.). Consequently, there is a given forecast of Ireland in the coming years. There is evaluated the impact of investment incentives on the development of the Irish economy and outlined the direction in which the incentives in Ireland will take in the near future.
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Stewart, Russel. "Brand loyalty in the South African tyre industry." Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/d1015983.
Full textAbstract:
The tyre industry plays an important role in the concept of mobility. Mobility defines the human need for transportation, which has been growing at an accelerated pace since the dawn of the nineteenth century. More importantly, modern mobility cannot be achieved without the use of a pneumatic tyre, a commodity that has become increasingly complex and competitive with countless brands and products available on a global scale. In order to stand out in this competitive market landscape, big brands attempt to build an amount of brand awareness within the market place, while maintaining a balance in creating a demand for their product in pull marketing strategies. While the market place becomes increasingly competitive on a both a global and local level, tyre brands are all trying various tactics in an effort to secure wheel positions on consumer’s vehicles. Within the marketing mix there are various strategies and tactics that can be adopted by tyre brands to secure a share of voice within the mind of the consumer when the need arises for new tyres, however in South Africa, only the established brands have the spending power to employ traditional media space in an effort to communicate with the consumer. It has also become increasingly difficult for established brands to remain dominant within the decision journey of consumers, especially when the retailer has the final contact with the consumer and may be promoting the purchase of a tyre brands that results in higher margins that the brand originally requested by the consumer. The tyre industry plays an important role in the concept of mobility. Mobility defines the human need for transportation, which has been growing at an accelerated pace since the dawn of the nineteenth century. More importantly, modern mobility cannot be achieved without the use of a pneumatic tyre, a commodity that has become increasingly complex and competitive with countless brands and products available on a global scale. In order to stand out in this competitive market landscape, big brands attempt to build an amount of brand awareness within the market place, while maintaining a balance in creating a demand for their product in pull marketing strategies. While the market place becomes increasingly competitive on a both a global and local level, tyre brands are all trying various tactics in an effort to secure wheel positions on consumer’s vehicles. Within the marketing mix there are various strategies and tactics that can be adopted by tyre brands to secure a share of voice within the mind of the consumer when the need arises for new tyres, however in South Africa, only the established brands have the spending power to employ traditional media space in an effort to communicate with the consumer. It has also become increasingly difficult for established brands to remain dominant within the decision journey of consumers, especially when the retailer has the final contact with the consumer and may be promoting the purchase of a tyre brands that results in higher margins that the brand originally requested by the consumer. The questions that remain are; do retailers have a high degree of influence on consumer behaviour or are high levels of brand awareness enough for a brand owner to be assured of a consistent demand on their product? This research aims to validate the interdependence of brand awareness and retailer influence on the consumer decision journey within the South African tyre industry. The research starts by setting the scene within the global and local tyre industry through the use of the Continental Corporation for illustration purposes. Once the scene is set in terms of the industry in which the research is taking place, brand theory is exhaustively discussed providing relevance and context within the tyre industry. Within the discussion of brand equity, the consumer decision journey and touch points are introduced as process and influence before the final purchase is made. With the theory of the tyre industry and branding covered, qualitative fieldwork was undertaken by two researchers at a tyre retail group in Tswane, South Africa. The fieldwork consisted of questionnaires that needed to be completed by consumers who had just concluded their purchase decision and were waiting in the retailer for the work to be concluded on their vehicle. The results of the fieldwork are extensively analysed and discussed upon which conclusions and recommendations for future research are drawn. The sample attained is sufficient for qualitative analysis; however the conclusions need to be read within the context of the sample size and geographical location in which the research was conducted. Further context was provided from the retail store owner who provided expert comment and insight based on experience within the industry and retail environment. The comment was utilised along with the theory to either validate or disprove findings, which formed the basis for recommendations for future research.
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Kahwagi-Janho, Hany. "Étude archéologique et architecturale de la zone de l’hippodrome de Tyr." Thesis, Paris 4, 2010. http://www.theses.fr/2010PA040054.
Full textAbstract:
Cette thèse a pour objet l’étude du secteur de l’hippodrome romain du site archéologique d’el-Bass à Tyr (Liban sud). Six monuments et structures archéologiques sont concernés : la route antique, l’arc monumental, l’aqueduc, l’hippodrome et les deux bains de factions qui lui sont associés. Une description détaillée du site et de son cadre archéologique, géographique et historique sera suivie d’une étude approfondie de chacun des monuments. Cette étude couvrira leurs divers aspects archéologiques, architecturaux, typologiques ainsi que les divers remaniements qu’ils subirent. L’ensemble sera accompagné de plusieurs approches comparatives avec des monuments contemporains similaires. Cette étude sera complétée par une analyse urbaine du site, qui traitera de la disposition des monuments les uns par rapport aux autres ainsi que par une étude chronologique qui présentera les diverses phases de son évolution, son développement et son abandonThis thesis has for object the survey of the sector of the Roman hippodrome of the archaeological site of el-Bass in Tyre (South Lebanon). Six monuments and archaeological structures are concerned: the ancient road, the monumental arch, the aqueduct, the hippodrome and the two faction baths that are associated to it. A detailed description of the site and its archaeological, geographical and historic setting will be followed by a deepened survey of each of the monuments. This survey will cover their various archaeological, architectural, typological aspects as well as the various overhauls that they underwent. The whole will be accompanied by several comparative approaches with similar contemporary monuments. This survey will be completed by an urban analysis of the site, which will be about the disposition of the monuments as well as by a chronological survey that will present the various phases of its evolution, its development and its abandonment
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Torra, i. Fernàndez Èric. "The influence of tyre air cavities on vehicle acoustics." Doctoral thesis, KTH, Farkost och flyg, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4132.
Full textAbstract:
The tonal character of the low frequency internal noise in cars is often due to energy transmission through the tyre at the first few eigenfrequencies of the air cavity of the tyre. The first acoustic mode in the air cavity of a typical stationary car tyre is approximately 224 Hz. At this frequency the tyre is comparatively stiff resulting in a high transmission of energy from the road wheel contact to the car body itself. In order to investigate possible means of reducing this effect, the acoustic field inside a tyre is modelled. Theoretically it is found that the pressure inside a tyre and the energy transmission through the tyre to the wheel axle and the car body can be reduced by adding a sound absorbing material inside the tyre. This was confirmed by measurements on stationary as well as rotating tyres with and without added sound absorption. For a rotating tyre there is a split of the natural frequency depending on the rotational speed of the tyre. Measurements in a standard passenger car reveal that the noise level inside the car is rather high in a fairly wide frequency range around 224 Hz at normal velocities. This tonal noise can be reduced by adding sound absorption inside a tyre. Models for the prediction and the reduction of the tonal noise are presented. Measured and predicted results are compared and the agreement is found to be good. It is found that the tonal noise can be reduced by up to 9 dB. The effects of the air cavity resonances on the external noise have also been studied. It is estimated that external tyre noise can be reduced 1 dB by adding a sound absorbing material inside tyres. For a car travelling on a road a strong acoustic field is induced between the floor of the car and the road. The impact of this acoustic field can be reduced by mounting a sound absorbing material underneath the car. It is estimated that the A-weighted sound pressure level close to a running car could be reduced by 3 dB by adding this type sound absorption. It is found that aluminium foam could be a suitable sound absorbing material which could be mounted inside tyres and underneath cars. The acoustic and dynamic properties of various types of aluminium foams are discussed. In particular measurement techniques for determining sound absorption at grazing incidence are investigated.QC 20100923
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Kelly, Daniel Patrick. "Lap time simulation with transient vehicle and tyre dynamics." Thesis, Cranfield University, 2008. http://dspace.lib.cranfield.ac.uk/handle/1826/4791.
Full textAbstract:
A numerical method is presented for the time optimal control of the race car. The method
is then used to perform the role of the driver in numerical simulations of manoeuvres at the
limit of race car performance. The method does not attempt to model the driver but rather
replaces the driver with methods normally associated with numerical optimal control. The
use of constraints on the method is then considered to represent the performance limits of
the human driver. The method simultaneously finds the optimal driven line and the driver
control inputs (steer, throttle and brake) to drive this line in minimum time. The method is
in principle capable of operation with arbitrarily complex vehicle models as it requires only
limited access to the vehicle model state vector. It also requires solution of the differential
equation representing the vehicle model in only the forward time direction and is hence
capable of simulating the full vehicle transient response. The impact of various vehicle
parameters on minimum manoeuvre time, driven line and vehicle stability is shown for a
number of representative manoeuvres using a quasi-steady state vehicle model. A similar
process is then carried out to analyse the effect of suspension springs and dampers using a
fully dynamic sprung vehicle model. The presented transient time optimal control method
is then compared with results obtained from a traditional quasi-steady state manoeuvre
time simulation method. A thermodynamic tyre model is developed and the time optimal
control algorithm is used to evaluate dynamic tyre temperature effects on lap time and
vehicle stability.