Thesis (M. Sc.)--Acadia University, 1997. / Includes bibliographical references.

Thesis (M.S.)--Florida State University, 2006. / Advisor: Robert Hart, Florida State University, College of Arts and Sciences, Dept. of Meteorology. Title and description from dissertation home page (viewed Sept. 26, 2006). Document formatted into pages; contains xiii, 98 pages. Includes bibliographical references.

In this thesis we describe how to estimate the distance spanned in the pants graph by a train track splitting sequence on a surface, up to multiplicative and additive constants. If some moderate assumptions on a splitting sequence are satisfied, each vertex set of a train track in it will represent a vertex of a graph which is naturally quasi-isometric to the pants graph; moreover the splitting sequence gives an edge-path in this graph so, more precisely, our distance estimate holds between the extreme points of this path. The present distance estimate is inspired by a result of Masur, Mosher and Schleimer for distances in the marking graph. However, we can apply their line of proof only after some manipulation of the splitting sequence: a rearrangement, changing the order the elementary moves are performed in, so that the ones producing Dehn twists are brought together; and then an untwisting, which suppresses the majority of these latter moves to give a new sequence, which does not end with the same track as before, but does not include any portion that is almost stationary in the pants graph. The required distance is then, up to constants, the number of splits occurring in the untwisted sequence. A consequence of our main theorem together with a result of Brock is that, given a pseudo-Anosov self-diffeomorphism ψ of a surface S, the maximal splitting sequence introduced by Agol gives us an estimate for the hyperbolic volume of the mapping torus built from S and ψ. There are also some interesting consequences for the hyperbolic volume of a solid torus minus a closed braid, via a machinery employed by Dynnikov and Wiest.

abstract: ABSTRACT The Spirit landing site in Gusev Crater has been imaged by the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (HiRISE) camera more than thirty times since 2006. The breadth of this image set allowed a study of changes to surface features, covering four Mars years. Small fields of bedforms comprised of dark material, and dark dust devil tracks are among the features revealed in the images. The bedforms are constrained within craters on the plains, and unconstrained in depressions less than 200m wide within the topography of the Columbia Hills, a ~120m-high structure in center of Gusev. Dust devil tracks appear in many images of the bedforms. Within the Columbia Hills, three bedform fields approximately 180m2 and composed of fine dark basaltic sand were studied, using five HiRISE images taken from 2006 to 2014. Both bedform crests and the dust devil tracks superimposed on them were evaluated for change to azimuth and length, and for correlation between the features. The linear to slightly sinuous transverse crests ranging from less than 1m to 113m in length and two to three meters in wavelength, are primary bedforms. During the study they shifted as much as 33 degrees in azimuth, and individual crests moved on the surface as much as 0.75m. The greatest changes corresponded to a global dust storm in 2007. Average crest movement was documented at the rate of 0.25m per year. Rather than moving progressively, the crests eventually returned to near their original orientation after the storm. The dust devil tracks, reflecting a more complex wind regime, including vortex development during diurnal heating, maintained predominantly NW-SE orientations but also reflected the effects of the storm. The observed modifications were neither progressive, nor strictly seasonal. The apparent stability of the bedform geometry over four seasons supports the predictions of the Mars Regional Atmospheric Modeling System (MRAMS): low speed (1-7.5 ms-1), daily alternating winds of relatively equal force. Crest profiles were found to be nearly symmetrical, without slipfaces to indicate a preferential wind direction; this finding also is supported by the MRAMS model. / Dissertation/Thesis / Masters Thesis Geological Sciences 2016

Made available in DSpace on 2014-10-09T12:53:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:34Z (GMT). No. of bitstreams: 1 11664.pdf: 905420 bytes, checksum: 20644e6d8e90a917c6c5df56691bdf5d (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA

Made available in DSpace on 2014-10-09T12:53:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:34Z (GMT). No. of bitstreams: 1 11664.pdf: 905420 bytes, checksum: 20644e6d8e90a917c6c5df56691bdf5d (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA

La progression de l'informatique dans nos vies s'accompagne de processus de production et de rétention massive de traces. Cette recherche avance l'hypothèse que l'être humain contemporain de l'informatique devenue diffuse fait dans son milieu technique l'épreuve d'un choc. Cette notion, entendue au sens que lui donna Walter Benjamin dans les années 1930, fait référence à la généralisation d'un décalage entre l'expérience vécue et l'expérience réelle. Sur le plan théorique et pratique, il s'agit de considérer la littérature comme une ressource pour donner demeure à ce qui reste inaperçu dans la fréquentation courante de l'informatique, afin de rendre l'expérience qui en est faite communicable. Qu'est ce que l'informatique fait à la littérature? Une pratique d'écriture contemporaine de l'informatique implique-t-elle nécessairement le recours aux nouvelles technologies ? L'analyse d'un corpus d'oeuvres hétérogène mettra en évidence différentes manières de concevoir les relations entre la littérature et l'informatique : l'informatique comme thème, l'informatique comme outil, et l'informatique comme matière ou matrice pour le texte littéraire. Face à l'éparpillement des données et la multiplication des sollicitations, des modalités de l'attention particulières sont à chercher. Il s'agira, compte tenu de ces différentes approches, de considérer certains principes formels de l'informatique (discrétisation, fragmentation, montage, agrégation, compilation, corrélation, etc.) et de les coupler à des principes d'écriture susceptibles de manifester le fait même de l'informatique. Cette tentative littéraire, attenante à la recherche, se présentera sous la forme de deux textes imprimés sur deux volumes distincts présentés en supplément de la thèse / The increased presence of information technology in our lives goes along with a process of massive production and retention of marks. This research puts forth the hypothesis according to which human beings contemporary to widespread information technology experience a shock in their technical environment. This notion, viewed in the sense that Walter Benjamin introduced in the 1930s, refers to the generalisation of a discrepancy between the experience that has been lived and the actual experience. From a theoretical and a practical point of view, literature shall be considered as a resource to bring to light what goes unnoticed to the common use of information technology, in order to give evidence for the experience that is indeed expressible. What does information technology do to literature ? Does a writing practice that is contemporary to information technology necessarily imply having recourse to new technology ? The analysis of a hetereogenous corpus of works will help highlight a variety of ways to consider the relationships between literature and information technology : information technology as a theme, (information technology) as a tool, and (information technology) as a material or matrix for the literary work. Faced with the scattering of data and proliferation of solicitations, specic modes of attention are to be looked for. Taking into consideration these different approaches, some formal principles of information technology (discretisation, fragmentation, montage, aggregation, compilation, correlation, etc.) shall be dealt with and coupled with writing principles that are likeley to express information technology itself. This literary attempt, contiguous to the research, shall take the form of two texts printed on two separate volumes, presented as a supplement to the thesis

In this study, three new reports of large felids from the Pleistocene are presented and discussed. A single partial left dentary from Jawbone Cave represents the first confirmed presence of S. fatalis in east Tennessee and was sampled for radiocarbon dating. Wind Tunnel and Chilly Bowl Cave are among the first records of P. onca to be identified confidently from Arkansas. Chilly Bowl Cave also produced two trackways attributable to Panthera sp., one set potentially belonging to P. atrox. In addition to the description of these remains and the caves they were found in, taxonomic histories for both S. fatalis and P. onca are explored to explain the choice of name used for each felid. Regional reviews of material of each taxon are also presented.

This thesis consists of two topics. The first topic is a performance assessment study of the flight operations in the North Atlantic Organized Track System. This study begins with the demand shortfall analysis of demand sets provided by the Federal Aviation Association (FAA). These sets were used to simulate OTS traffic for a number of scenarios that consider different separation minima. For this reason, algorithms were developed to modify the NAT OTS configuration applying reduced lateral separation between tracks and estimate the probability that any given flight that traverses the Atlantic will use the OTS. The preliminary results showed that the scenario with reduced lateral separation minimum (RLatSM) (25 nm) and the reduced longitudinal separation minimum (RLongSM) (8 nm) was the most optimal among all five that were simulated. The application of RLatSM also decrease the mean fuel consumption of flights that shift from traversing the OTS to flying random routes. The second topic is a noise study performed for the Chicago O'Hare International Airport. The contributions to this topic were three fold: 1) we analyzed data to understand the current operations at ORD airport 2) we verified the noise contours produced in 2002 by the FAA, Chicago Department of Aviation (CDA) and the engineering contractors 3) we produced noise contours for today's airport activity. / Master of Science

A new failure criterion for discriminating good and bad (overheated) railroad car wheels is proposed. This criterion can replace the conventional “four inch" discoloration rule. The procedure for the new discrimination criterion is based on the fluctuations of the azimuthal residual stress in the tread of the wheel. This criterion is based on a maximum likelihood statistical analysis of data obtained from six different wheels as deterrmined by x-ray diffraction. Of these locations, the analysis showed the tread, and perhaps a critical point on the top of the flange, to be the most sensitive to residual stress. The variance analysis showed that fluctuations in stress at the most sensitive location in the tread appeared to be related to the service history. The residual stresses showed an oscillatory pattern in the hoop direction around the wheels. Extension of the measurement technology to the use of magnetoelastic stress measurement is proposed. To evaluate the inaccuracy in stress data possible from a large sample with curved surface, corrections for a deliberate tilt of the plane of the x-ray diffractometer from the normal to the sample surface have been developed. Analysis of different misalignments are discussed. To validate our x-ray residual stress data, residual stresses were also measured by hole drilling. Excellent agreement between two techniques was found. Finally, stress variation with depth below surface was determined by the hole drilling technique. / Ph. D.