Dissertations / Theses on the topic 'Collapsing'
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Sandireddy, Raja Kiran Kumar Reddy Agrawal Vishwani D. "Hierarchical fault collapsing for logic circuits." Auburn, Ala., 2005. http://repo.lib.auburn.edu/EtdRoot/2005/SPRING/Electrical_and_Computer_Engineering/Thesis/SANDIREDDY_RAJA-KIRAN-KUMAR_48.pdf.
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Dibben, Susan. "A microstructural model for collapsing soils." Thesis, Nottingham Trent University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266820.
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Fujioka, Tadashi. "Fibration theorems for collapsing Alexandrov spaces." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263435.
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Melick, William R. "Collapsing exchange rate regimes under governmental optimization /." Connect to resource, 1987. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1262710081.
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Grimm, Douglas. "The dynamics of collapsing Bose-Einstein condensates." View electronic text, 2002. http://eprints.anu.edu.au/documents/disk0/00/00/07/64/index.html.
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Thesis (BSc. (Hons))--Australian National University, 2002.Available via the Australian National University Library Electronic Pre and Post Print Repository. Title from title screen (viewed Mar. 28, 2003). "A thesis submitted for the degree of Bachelor of Science with Honours of The Australian National University" Bibliography: p. 45.
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Doshi, Alok Shreekant Agrawal Vishwani D. "Independence fault collapsing and concurrent test generation." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Spring/master's/DOSHI_ALOK_48.pdf.
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Gamez, David. "Positive scepticism and the collapsing hermeneutic circle." Thesis, University of Essex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369401.
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Melick, William Robert. "Collapsing exchange rate regimes under governmental optimization." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1262710081.
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Semple, James Fraser. "Completion of restricted Lie algebras and collapsing groups." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316874.
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Grady, Keith J. "Solar flare particle acceleration in collapsing magnetic traps." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/2839.
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The topic of this thesis is a detailed investigation of different aspects of the particle acceleration mechanisms operating in Collapsing Magnetic Traps (CMTs), which have been suggested as one possible mechanism for particle acceleration during solar flares. The acceleration processes in CMTs are investigated using guiding centre test particle calculations. Results including terms of different orders in the guiding centre approximation are compared to help identify which of the terms are important for the acceleration of particles. For a basic 2D CMT model the effects of different initial conditions (position, kinetic energy and pitch angle) of particles are investigated in detail. The main result is that the particles that gain most energy are those with initial pitch angles close to 90° and start in weak field regions in the centre of the CMT. The dominant acceleration mechanism for these particles is betatron acceleration, but other particles also show signatures of Fermi acceleration. The basic CMT model is then extended by (a) including a magnetic field component in the invariant direction and (b) by making it asymmetric. It is found that the addition of a guide field does not change the characteristics of particle acceleration very much, but for the asymmetric models the associated energy gain is found to be much smaller than in symmetric models, because the particles can no longer remain very close to the trap centre throughout their orbit. The test particle method is then also applied to a CMT model from the literature which contains a magnetic X-line and open and closed field lines and the results are compared with the previous results and the findings in the literature. Finally, the theoretical framework of CMT models is extended to 2.5D models with shear flow and to fully 3D models, allowing the construction of more realistic CMT models in the future.
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De, Sousa Vinagre Tiberio J. V., and Sousa Vinagre Tiberio J. V. De. "Expansive and collapsing behaviour of volume change soils." Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/23594.
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This thesis is designed to achieve three goals: Goal One - to introduce the reader to soils exhibiting expansive and/or collapsing behaviour; Goal Two - to provide an in depth understanding of aspects of this behaviour, obtained from an extensive study of these soil types; and, Goal Three - to serve as a reference for future research work (a recommendation for further research proposed in Chapter Ten of this thesis). The thesis is divided in two main parts. In the first part representative soil types were selected on the basis of their properties and expected engineering behaviour. The soil structure and clay minerals were also studied in part one of this thesis. The second part of the thesis deals with aspects of expansive and collapsing behaviour of soils. Chapter three provides the introduction to the subsequent chapters on expansive and collapsing behaviour of volume change soils.
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Nomura, Hideko. "Angular Momentum Transfer in Dynamically Collapsing Gaseous Disks." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/150830.
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Hu, Mike. "A Collapsing Method for Efficient Recovery of Optimal Edges." Thesis, University of Waterloo, 2002. http://hdl.handle.net/10012/1144.
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In this thesis we present a novel algorithm, HyperCleaning*, for effectively inferring phylogenetic trees. The method is based on the quartet method paradigm and is guaranteed to recover the best supported edges of the underlying phylogeny based on the witness quartet set.
This is performed efficiently using a collapsing mechanism that employs memory/time tradeoff to ensure no loss of information. This enables HyperCleaning* to solve the relaxed version of the Maximum-Quartet-Consistency problem feasibly, thus providing a valuable tool for inferring phylogenies using quartet based analysis.
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Otis, Evan T. "An Analysis of the Film Industry's Collapsing Video Window." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/cmc_theses/533.
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The collapse of the video window is disrupting the economic framework between exhibitors and distributors in the film industry. This study analyzes the collapse from several angles and provides a detailed description as to why the collapse has, and will continue to be, disruptive. I first examine the impact various technologies have had on the collapse of the video window – the time between a motion picture’s theatrical release and video release – during 1997 – 2012. The average video window has declined from 5 months 22days in 1997 to 3 months 29 days in 2012. Differences of means tests were used to inspect the average video window at the time of each technology’s introduction. Then in order to reveal how the length of the video window affects box office profit, I use an ordinary least squares regression to examine the determinants of gross domestic box office profit for a sample of 294 top earning U.S. films during 1999-2012.
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Dixon, Kael. "Collapsing fibres under Kähler Ricci flow on Hirzebruch manifolds." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/27806.
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In this article we study the Kähler Ricci flow on a class of ℂℙ¹ bundles over ℂℙⁿ⁻¹ known as Hirzebruch manifolds. These are defined by ℙ(Hⁱ⊕ℂ-1), where H is the canonical line bundle, ℂ is the trivial line bundle, and n,i∈ℕ. We follow the work by Song and Weinkove, who study solutions to the Kähler Ricci flow for a Calabi symmetric Kähler metrics on Hirzebruch manifolds. They were able to show that, depending on the initial Kähler class, the Ricci flow would reach a finite time singularity corresponding to the manifold either shrinking to a point, contracting the zero section to a point, or collapsing the fibres. In this paper, we investigate how the fibres collapse in the latter case with the further assumptions that the singularity is formed at a type I rate, and that the length of a generic vector does not decay too quickly in some sense. In this case we show that the fibres converge to round spheres after blowing up around a singular point on a fibre.
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Eradat, Oskoui Solmaz. "New aspects of particle acceleration in collapsing magnetic traps." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/11954.
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Collapsing magnetic traps (CMTs) have been suggested as one of the mechanisms that could contribute to particle energisation in solar flares. The basic idea behind CMTs is that charged particles will be trapped on the magnetic field lines below the reconnection region of a flare. This thesis discusses a number of important new aspects in particle energisation processes in CMTs, based on the model by Giuliani et al. (2005). In particular, we extend previous studies of particle acceleration in this CMT model to the relativistic regime and compare our results obtained using relativistic guiding centre theory with results obtained using the non-relativistic guiding centre theory. The similarities and differences found are discussed. We then present a detailed study of the question, what leads to the trapping or escape of particle orbits from CMTs. The answer to this question is investigated by using results from the non-relativistic orbit calculations with guiding centre theory and a number of simple models for particle energy gain in CMTs. We find that there is a critical pitch angle dividing trapped particle orbits from the escaping particle orbits and that this critical pitch angle does not coincide with the initial loss cone angle. Furthermore, we also present a calculation of the time evolution of an anisotropic pressure tensor and of the plasma density under the assumptions that they evolve in line with our kinematic MHD CMT model and that the pressure tensor satisfies the double-adiabatic Chew-Goldburger-Low (CGL) theory. Finally, we make a first step to introduce Coulomb scattering by a Maxwellian background plasma into our guiding centre equations by changing them into a set of stochastic differential equations. We study the influence of a static background plasma onto selected particle orbits by pitch angle scattering and energy losses, and look at its effect on the particle energy and the trapping conditions.
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Streil, Manuel [Verfasser], and Bernd [Akademischer Betreuer] Ammann. "Yamabe constants of collapsing Riemannian submersions / Manuel Streil ; Betreuer: Bernd Ammann." Regensburg : Universitätsbibliothek Regensburg, 2016. http://d-nb.info/1118846443/34.
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Kuan, Seng How. "Collapsing bubble bed in a downcomer with the introduction of solvent." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116862.
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The original goal was to use a downcomer to create swarms of solvent-coated bubbles to scale-up the air-assisted solvent extraction (AASX) process. The downcomer provides a close-packed bubble bed considered attractive for solvent coating and fast extraction kinetics. During initial testing, the bubble bed was observed to collapse upon introduction of solvent, evident from decreasing gas holdup, decreasing aspirated air rate, and formation of air slugs. Neither changing solvent introduction technique, solvent composition nor addition of frother or salt alleviated the situation. In many cases collapse was complete (air rate became zero) at less than 900 ppm solvent. Thus, the focus shifted to address this phenomenon. Because conditions in the bubble bed approach those of foam (gas holdup over 45%), the de-foaming action of oil droplets was thought to be responsible, the solvent taking the role of de-foaming agent. The mechanism is related to oil droplets bridging and/or spreading to destabilize the inter-bubble film. Testing two hydrophobic solids, talc and graphite, showed that solids did not collapse the bed suggesting that the solvent's ability to spread gives the de-foaming (bed collapse) effect. A setup was established to view coalescence of two bubbles held in proximity when exposed to circulating dispersions of solvent, solid and solvent/solid. Conditions giving coalescence generally agreed with those yielding bed collapse, including the MIBC/talc system which resisted coalescence and bed collapse on introduction of solvent. Solvent bridging was captured on video although spreading was not observed. In conclusion the downcomer is not suited to AASX. The unit is used in Jameson Cells employed to remove solvent droplets in SX plants. The solvent levels appear to be less than 200 ppm where collapse is only partial and the phenomenon may not be noticed in those applications.Le premier objectif de la recherche consistait à faire usage d'une goulotte de façon à créer des bulles enrobées de solvant afin d'augmenter l'échelle de mesure pour l'extraction au solvant par air assisté (AASX). La goulotte assure un contact plus étroit entre la bulle et le solvant et celui est considéré comme avantageux pour l'enrobement des bulles du solvant et pour la cinétique d'extraction rapide. Lors des tests initiaux, l'effondrement du lit formé par les bulles dans la goulotte, était observé à l'introduction du solvant comme le démontre le bas niveau du gaz, la diminution du débit de l'air aspiré, et la formation des grandes bulles d'air. L'on a observé qu'en changeant de technique d'introduction du solvant, la composition du solvant, et en ajoutant du sel et du moussant, le problème restait entier. Puisque les conditions dans le lit des bulles dans la goulotte avoisinent celles de la mousse (niveau de gaz plus que 45%), les propriétés des gouttelettes de solvant étaient tenues pour responsables, les gouttelettes de solvant jouant le rôle d'agent démousseur. Ce faisant, la recherche s'est penchée sur ce phénomène. Le mécanisme est lié à l'action de formation de pont (entre les bulles) et/ou l'enrobement des bulles par des gouttelettes de solvant. Celles-ci déstabilisent le film entre les bulles. Plus d'investigations sur les effets des matériaux hydrophobique sur la stabilité du lit des bulles en comparant le solvant à deux solides hydrophobiques, le talc et le graphite, avaient révélé que les solides n'avaient pas produit l'effondrement, sinon favorisé la stabilité: Ceci suggère l'habileté du solvant à s'étaler, ce qui confère la propriété démoussante (effondrement du lit). En conséquence, un montage avait été fait pour visualiser la coalescence entre deux bulles de plus prés, lorsque celles-ci étaient exposées à la circulation des dispersions de solvant, solide et des mélanges solvant/solides. Les résultats ont montré que les conditions entrainant la coalescence s'accordaient bien avec celles qui engendraient l'effondrement du lit dans la goulotte. Le pont formé entre les bulles et le solvant avait été capté par vidéo alors que l'étalement ne l'était pas. En conclusion, la goulotte n'est pas indiquée pour l'extraction au solvant par air assisté (AASX). L'unité est utilisée dans la cellule de Jameson pour éliminer les gouttelettes de solvant dans les unités d'extraction. Le niveau de solvant est moins de 200 ppm et dans ce cas, l'effondrement est partiel et le phénomène n'est peut-être pas observé dans ces applications.
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Palestro, James J. "Some Tasks' Demands Require Collapsing Bounds: Evidence from a Behavioral Analysis." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1514901294586086.
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Hu, Michael. "A collapsing method for efficient recovery of optimal edges in phylogenetic trees." Waterloo, Ont. : University of Waterloo, [Dept. of Computer Science], 2002. http://etd.uwaterloo.ca/etd/mhu2002.pdf.
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Thesis (M.Math.)--University of Waterloo, 2002."A thesis presented to the University of Waterloo in fulfilment of the thesis requirement for the degree of Master of Mathematics in Computer Science". Includes bibliographical references.
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Fleischmann, Pamela [Verfasser]. "On Special k-Spectra, k-Locality, and Collapsing Prefix Normal Words / Pamela Fleischmann." Kiel : Universitätsbibliothek Kiel, 2021. http://d-nb.info/1232812528/34.
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Rees, Samuel Huw. "The collapsing pillar : Jimmy Carter and US foreign policy towards Iran, 1977-1981." Thesis, Swansea University, 2013. https://cronfa.swan.ac.uk/Record/cronfa43014.
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The continuing diplomatic impasse between the United States and Iran dates back to the turbulent events of the late 1970s. Blame for the 'loss' of Iran, which had been one of the 'twin pillars' of US strategy in the Persian Gulf, has inevitably fallen on the White House incumbent at the time, President Jimmy Carter. This thesis offers a reassessment of Carter's decision making and his responses to the fall of the Shah, the Islamic Revolution and the US embassy hostage taking. It demonstrates that the breakdown of US-Iranian relations was not simply a one-president phenomenon and, more significantly, Carter's handling of Iran was not as dire as it is often portrayed. The research is based on a thorough examination of the available archive material, including newly released documents, as well as recent interviews with the major protagonists. When Carter took office in 1977 he inherited a badly creaking Iranian pillar that was soon to collapse altogether. The flawed policies of his predecessors placed strict limitations on his administration and unwittingly created a ticking time bomb in the form of the Shah. Despite these restrictions, Carter battled to reconcile the strategic necessities of Cold War containment with his moral principles in areas such as human rights and arms sales. In an administration seemingly dominated by the disagreements amongst his top two advisors, Carter remained the key decision maker at all times. He recognised the practical limits of American power and assumed sensible positions in response to an ever changing and uncontrollable crisis. Aside from its contemporary significance, Iran is therefore critical to Carter's disputed legacy and how he rates as a foreign policy president.
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Pereira, Jose Henrique Feitosa. "Numerical analysis of the mechanical behavior of collapsing earth dams during first reservoir filling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ32808.pdf.
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ALI, MOLLA MOHAMMAD. "A PROBABILISTIC ANALYSIS OF THE DISTRIBUTION OF COLLAPSING SOIL IN TUCSON USING KRIGING METHOD." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184180.
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An analytical investigation was carried to determine the nature and extent of the variability of selected collapse criteria and collapse-related soil parameters both areally and with depth within the city of Tucson. Collapse-related soil parameters of about 1000 sample points from over 400 borehole locations throughout the Tucson basin were collected from several consulting geotecnical engineering offices of the city. Statistical analysis on seven data sets corresponding to six different depth increments below the surface showed high dispersion tendencies expressed by the value of coeffecient of variation (cov). The value of cov was found to increase linearly with depth for most criteria and parameters. All the collapse criteria and collapse-related soil parameters were found to follow the Gamma distribution function except insitu dry density bd) and porosity (n₀) which were found to follow the Weibull distribution function. A polynomial regression model developed for the collapse parameter Cp showed that it varies with depth almost linearly. A stepwise regression analysis revealed that the collapse parameter Cp is strongly correlated with γd and insitu moisture content, woo Factor analysis validates this finding by producing two strong factors γd and insitu degree of saturation, s₀ which described almost 80% of the variation encountered in the data. The application of geostatistical concepts was found to be feasible in analyzing the collapse criteria and collapse-related soil parameters. Almost all criteria and parameters were strongly dependent spatially. A spherical variogram model was found to be appropriate for them. The method of Ordinary Kriging provided an unbiased estimation of a parameter at an unsampled location with known estimation variance. The method of Indicator Kriging was used to develop contour plots for the various data sets that showed the probability that the value of a certain parameter is above or below a critical level. These contour plots can be used to identify the areas within the City of Tucson that contain soils having a low- medium- or high-collapse potential. The ability to predict the occurence of such soils with a known degree of certitude is invaluable to planners, developers and geotechnical engineers.
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May, Russell J. "A Collapsing Result Using the Axiom of Determinancy and the Theory of Possible Cofinalities." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc2789/.
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Assuming the axiom of determinacy, we give a new proof of the strong partition relation on ω1. Further, we present a streamlined proof that J<λ+(a) (the ideal of sets which force cof Π α < λ) is generated from J<λ+(a) by adding a singleton. Combining these results with a polarized partition relation on ω1
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Lam, Fung Ming. "A contrastive structural analysis of Chinese and English newspapers of a collapsing building accident." HKBU Institutional Repository, 2002. http://repository.hkbu.edu.hk/etd_ra/369.
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Weyhausen, Andreas [Verfasser], Bernd [Akademischer Betreuer] Brügmann, Gottfried [Akademischer Betreuer] Tichy, and Mark [Akademischer Betreuer] Hannam. "Numerical methods for collapsing gravitational waves / Andreas Weyhausen. Gutachter: Bernd Brügmann ; Gottfried Tichy ; Mark Hannam." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2015. http://d-nb.info/1077007175/34.
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Groomes, Sally Anne. "Collapsing the binary reconsidering faith, feminism, and convention in the works of Elizabeth Stuart Phelps /." Click here for download, 2009. http://proquest.umi.com/pqdweb?did=1691880051&sid=1&Fmt=2&clientId=3260&RQT=309&VName=PQD.
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Field, Ann-Marie. "Collapsing the universal : towards a framework for understanding the politics of difference in liberal democratic states." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq25971.pdf.
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Faria, Mary Frances Veloz. "A non-traditional way to manage change : collapsing hierarchy temporarily to allow for collective knowledge work /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Whitfield, Steven M. "Enigmatic Faunal Declines at La Selva, Costa Rica: Patterns and Processes in a Collapsing Neotropical Herpetofauna." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/435.
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Amphibian populations are declining even in pristine areas in many parts of the world, and in the Neotropics most such enigmatic amphibian declines have occurred in mid- to high-elevation sites. However, amphibian populations have also declined at La Selva Biological Station in the lowlands of Costa Rica, and similar declines in populations of lizards have occurred at the site as well. To set the stage for describing amphibian declines at La Selva, I thoroughly review knowledge of amphibian decline and amphibian conservation in Central America: I describe general patterns in biodiversity, evaluate major patterns in and ecological correlates of threat status, review trends in basic and applied conservation literature, and recommend directions for future research. I then synthesize data on population densities of amphibians, as well as ecologically similar reptiles, over a 35-year periods using quantitative datasets from a range of studies. This synthesis identifies assemblage-wide declines of approximately 75% for both amphibians and reptiles between 1970 and 2005. Because these declines defy patterns most commonly reported in the Neotropics, it is difficult to assess causality evoking known processes associated with enigmatic decline events. I conduct a 12-month pathogen surveillance program to evaluate infection of frogs by the amphibian chytrid fungus, an emerging pathogen linked to decline events worldwide Although lowland forests are generally believed to be too warm for presence or adverse population effects of chytridiomycosis, I present evidence for seasonal patterns in infection prevalence with highest prevalence in the coolest parts of the year. Finally, I conducted a 16-month field experiment to explore the role of changes to dynamics of leaf litter, a critical resource for both frogs and lizards. Population responses by frogs and lizards indicate that litter regulates population densities of frogs and lizards, particularly those species with the highest decline rate. My work illustrates that sites that are assumed to be pristine are likely impacted by a variety of novel stressors, and that even fauna within protected areas may be suffering unexpected declines.
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Soliday, Stanley Jr. "Limits of limit equilibrium and finite element techniques applied to cracked debris dams on collapsing foundations." PDXScholar, 1991. https://pdxscholar.library.pdx.edu/open_access_etds/4428.
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Limits of slope stability, limit equilibrium methods, and of the finite element code FEADAM are reached in the application of these methods to the problem of cracked dams constructed on collapsing soils.
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Katsaris, Apostolos. "Periodically collapsing speculative bubbles : an empirical investigation of the S&P 500 Composite Index, 1888-2001." Thesis, University of Reading, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430843.
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Demba, Susanne. "Sensor-based detection of the teat load caused by a collapsing liner using a pressure-indicating film." Doctoral thesis, Humboldt-Universität zu Berlin, 2017. http://dx.doi.org/10.18452/18564.
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Ziel der Arbeit war es zum Einen die Eignung der Messung statischer Drücke in unterschiedlichen Größenordnungen mit Hilfe von roter Farbdichtevariation zur direkten Messung des Druckes zwischen Zitze und Zitzengummi beim Melken zu testen. Zum Anderen wurden verschiedene Einflussfaktoren auf diesen Druck analysiert. Dafür wurden Untersuchungen im Versuchsmelkstand unter der Verwendung verschiedener Zitzenmodelle durchgeführt. Der Einfluss verschiedener Anlagenvakua, Pulsationsraten, Pulsphasenverhältnisse und Zitzengummis auf die Zitzenbelastung wurde umfangreich analysiert.
Es wurde festgestellt, dass sich die getestete Methode zur direkten Messung des Druckes zwischen Zitze und Zitzengummi eignet. Des Weiteren konnte ein signifikanter Einfluss aller getesteten Faktoren nachgewiesen werden. Die Zitzenbelastung beim Melken nimmt mit ansteigendem Anlagenvakuum, ansteigender Pulsationsrate und ansteigendem Phasenverhältnis zu. Die technischen Eigenschaften eines Zitzengummis, vor allem aber die Form des Zitzengummischaftes, unterscheiden sich signifikant hinsichtlich des von ihnen applizierten Druckes auf die Zitze. In allen Untersuchungen wurde der größte Druck auf das Zitzenende ausgeübt.The aim of the present thesis was to test whether the measurement of static pressure distribution and magnitude with the aid of red color density variation is appropriate to directly measure the teat load caused by a collapsing liner and to identify different factors influencing this load. Therefore, investigations were carried out in a laboratory milking parlor using different artificial teats. The influence of the machine vacuum, the pulsation rate, the pulsation ratio, and the liner type were analyzed. The present investigations showed that the tested method is appropriate to directly measure the teat load due to liner collapse. A significant effect of all tested factors could be found as well. The higher the machine vacuum, pulsation rate, and pulsation ratio, the higher the teat load caused by a collapsing liner. The technical characteristics of a liner, especially the shape of the barrel, differ significantly with regard to the teat load. In all investigations more pressure was applied to the teat end.
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Staeheli, Paul W. "Collapsing insurgent organizations through leadership decapitation a comparison of targeted killing and targeted incarceration in insurgent organizations /." Thesis, Monterey, California : Naval Postgraduate School, 2010. http://edocs.nps.edu/npspubs/scholarly/theses/2010/Mar/10Mar%5FStaeheli.pdf.
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Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, March 2010.Thesis Advisor(s): Freeman, Michael. Second Reader: Tucker, David. "March 2010." Description based on title screen as viewed on April 26, 2010. Author(s) subject terms: Targeted Killing, Targeted Incarceration, Leadership Decapitation, Capture versus Kill, Counterinsurgency, al Qaeda, Taliban. Includes bibliographical references (p. 71-74). Also available in print.
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Al-Gasous, K. A. "The deformation behaviour of the collapsing and destructured soils of the Sana'a area and their response to field treatment." Thesis, Aston University, 1995. http://publications.aston.ac.uk/14258/.
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Previous work has indicated the presence of collapsing and structured soils in the surface layers underlying Sana's, the capital of Yemen Republic. This study set out initially to define and, ultimately, to alleviate the problem by investigating the deformation behaviour of these soils through both field and laboratory programmes. The field programme was carried out in Sana'a while the laboratory work consisted of two parts, an initial phase at Sana's University carried out in parallel with the field programme on natural and treated soils and the major phase at Aston University carried out on natural, destructured and selected treated soils. The initial phase of the laboratory programme included classification, permeability, and single (collapsing) and double oedometer tests while the major phase, at Aston, was extended to also include extensive single and double oedometer tests, Scanning Electron Microscopy and Energy Dispersive Spectrum analysis. The mechanical tests were carried out on natural and destructed samples at both the in situ and soaked moisture conditions. The engineering characteristics of the natural intact, field-treated and laboratory destructured soils are reported, including their collapsing potentials which show them to be weakly bonded with nil to severe collapsing susceptibility. Flooding had no beneficial effect, with limited to moderate improvement being achieved by preloading and roller compaction, while major benefits were achieved from deep compaction. From these results a comparison between the soil response to the different treatments and general field remarks were presented. Laboratory destructuring reduced the stiffness of the soils while their compressibility was increasing. Their collapsing and destructuring mechanisms have been examined by studying the changes in structure accompanying these phenomena. Based on the test results for the intact and the laboratory destructured soils, a simplified framework has been developed to represent the collapsing and deformation behaviour at both the partially saturated and soaked states, and comments are given on its general applicability and limitations. It has been used to evaluate all the locations subjected to field treatment. It provided satisfactory results for the deformation behaviour of the soils destructed by field treatment. Finally attention is drawn to the design considerations together with the recommendations for the selection of potential improvement techniques to be used for foundation construction on the particular soils of the Sana's region.
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Jacquet, Philippe. "Nouvelles méthodes de modélisation neutronique des réacteurs rapides de quatrième Génération." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00680530.
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Les critères de sureté qui régissent le développement de coeurs de réacteurs dequatrième génération implique l'usage d'outils de calcul neutronique performants. Unepremière partie de la thèse reprend toutes les étapes de modélisation neutronique desréacteurs rapides actuellement d'usage dans le code de référence ECCO. La capacité desmodèles à décrire le phénomène d'autoprotection, à représenter les fuites neutroniques auniveau d'un réseau d'assemblages combustibles et à générer des sections macroscopiquesreprésentatives est appréciée sur le domaine des réacteurs rapides innovants respectant lescritères de quatrième génération. La deuxième partie de ce mémoire se consacre à lamodélisation des coeurs rapides avec réflecteur acier. Ces derniers nécessitent ledéveloppement de méthodes avancées de condensation et d'homogénéisation. Plusieursméthodes sont proposées et confrontées sur un problème de modélisation typique : le coeurZONA2B du réacteur maquette MASURCA.
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Greenfield, Sarah. "Type-2 fuzzy logic : circumventing the defuzzification bottleneck." Thesis, De Montfort University, 2012. http://hdl.handle.net/2086/7088.
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Type-2 fuzzy inferencing for generalised, discretised type-2 fuzzy sets has been impeded by the computational complexity of the defuzzification stage of the fuzzy inferencing system. Indeed this stage is so complex computationally that it has come to be known as the defuzzification bottleneck. The computational complexity derives from the enormous number of embedded sets that have to be individually processed in order to effect defuzzification. Two new approaches to type-2 defuzzification are presented, the sampling method and the Greenfield-Chiclana Collapsing Defuzzifier. The sampling method and its variant, elite sampling, are techniques for the defuzzification of generalised type-2 fuzzy sets. In these methods a relatively small sample of the totality of embedded sets is randomly selected and processed. The small sample size drastically reduces the computational complexity of the defuzzification process, so that it may be speedily accomplished. The Greenfield-Chiclana Collapsing Defuzzifier relies upon the concept of the representative embedded set, which is an embedded set having the same defuzzified value as the type-2 fuzzy set that is to be defuzzified. By a process termed collapsing the type-2 fuzzy set is converted into a type-1 fuzzy set which, as an approximation to the representative embedded set, is known as the representative embedded set approximation. This type-1 fuzzy set is easily defuzzified to give the defuzzified value of the original type-2 fuzzy set. By this method the computational complexity of type-2 defuzzification is reduced enormously, since the representative embedded set approximation replaces the entire collection of embedded sets. The strategy was conceived as a generalised method, but so far only the interval version has been derived mathematically. The grid method of discretisation for type-2 fuzzy sets is also introduced in this thesis. Work on the defuzzification of type-2 fuzzy sets began around the turn of the millennium. Since that time a number of investigators have contributed methods in this area. These different approaches are surveyed, and the major methods implemented in code prior to their experimental evaluation. In these comparative experiments the grid method of defuzzification is employed. The experimental results show beyond doubt that the collapsing method performs the best of the interval alternatives. However, though the sampling method performs well experimentally, the results do not demonstrate it to be the best performing generalised technique.
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Fleischmann, Pamela [Verfasser], Dirk [Akademischer Betreuer] Nowotka, Tero [Gutachter] Harju, and Richard [Gutachter] Weidmann. "On Special k-Spectra, k-Locality, and Collapsing Prefix Normal Words / Pamela Fleischmann ; Gutachter: Tero Harju, Richard Weidmann ; Betreuer: Dirk Nowotka." Kiel : Universitätsbibliothek Kiel, 2021. http://d-nb.info/1231275863/34.
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Yonkers, Nicole L. "Toll-like Receptor Tolerance in Dendritic Cells During Hepatitis C and HIV Infections: Collapsing the Bridge Between Innate and Adaptive Immunity." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1298412448.
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Gildenhuys, Nanine. "The occurrence and extent of collapse settlement in residual granite in the Stellenbosch area." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5214.
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Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Large areas of the earth’s surface are covered by soils that are susceptible to large decreases in bulk volume when they become saturated. These soils are termed collapsing soils and are very common in parts of the USA, Asia, South America and Southern Africa. This study is concerned with the occurrence of these collapsible soils in the residual granites of the Stellenbosch area. The study was undertaken as relatively little is known about the collapse phenomenon in the problematic weathered granites of the Western Cape. The majority of research thus far has been carried out on the deep residual soils formed on basement-granite in the Transvaal areas, whereas little attention has been paid to the Cape granites. The aim of the study was achieved through the experimental work which included double oedometer testing, indicator analyses and shear strength testing. Double oedometer tests were performed to quantify the potential collapse settlement of the soils from the demarcated study area. To provide a better understanding of the collapse behaviour of the soils, indicator analysis, which included Atterberg limits and particle size distributions, were performed. Direct shear tests were further carried out on saturated and natural moisture content specimens to establish the effect of collapsibility on shear strength and whether substantial additional settlement of the saturated soils would occur during shear. It was found that collapsible soils are prevalent in the demarcated study area as the majority of soils showed a potential collapse settlement of 1% or more. Collapse exceeding 5% were calculated in a few instances proving some soils to be highly collapsible. The double oedometer and indicator analysis results were used in an attempt to obtain a relationship between collapse settlement and a combination of easily determined properties such as dry density (void ratio), moisture content and grading, but no meaningful conclusions have emerged. The shear strength tests indicated that a clear correlation does not exist between collapsibility and shear strength. It was further established that a relationship between collapse settlement determined during the double oedometer testing and the volume change during shear strength testing cannot be assumed. It can thus be concluded that soils can be very unpredictable and further research on the collapse phenomenon is indicated.
AFRIKAANSE OPSOMMING: Groot dele van die aarde se oppervlakte is bedek deur grondtipes wat geneig is tot ‘n afname in volume as dit deurweek word. Hierdie gronde word swigversakkende gronde genoem en dit word algemeen teëgekom in dele van die VSA, Asië, Suid-Amerika en Suider-Afrika. In hierdie studie word die voorkoms van swigversakkende gronde in die residuele graniet in die Stellenbosch area ondersoek. Die studie is onderneem aangesien relatief min i.v.m. die swigversakking-verskynsel in die problematiese verweerde graniet van die Weskaap bekend is. Die meeste van die navorsing sover is onderneem op die diep residuele gronde wat gevorm is op die Argaïese graniet in die Transvaal gebied, en betreklik min aandag is geskenk aan die Kaapse graniet. Tydens die studie is eksperimente wat dubbele oedometer toetse, indikator analises, en skuifsterkte toetse insluit, uitgevoer. Dubbele oedometer toetse is uitgevoer om die potensiële swigversakking van die grond in die afgebakende studiegebied te kwantifiseer. In ‘n poging om die swigversakking-verskynsel van die grond beter te verstaan, is indikator analises wat Atterberg grense en partikel grootte verspreiding insluit, uitgevoer. Direkte skuiftoetse is ook uitgevoer op deurweekte grondmonsters en op monsters wat natuurlike vog bevat, om sodoende die effek van swigversakking op skuifsterkte vas te stel en om uit te vind of aansienlike addisionele sakking van die deurweekte gronde tydens skuif plaasvind. Daar is gevind dat swigversakkende gronde die oorheersende grondtipe in die afgebakende studiegebied is waar meeste van die gronde ‘n potensiële swigversakking van meer as 1% toon. ‘n Swigversakking van meer as 5% is in ‘n paar gevalle bereken, wat bewys dat sommige grondtipes hoogs versakkend is. Die resultate van die dubbele oedometer en indikator analises is gebruik in ‘n poging om te bewys dat daar ‘n verhouding bestaan tussen swigversakking en ‘n kombinasie van kenmerke wat maklik vasgestel kan word soos droë digdheid (ruimte verhouding), voginhoud en gradering, maar daar kon nie tot ‘n sinvolle slotsom gekom word nie. Die skuifsterkte toetse toon dat daar nie ‘n duidelike korrelasie bestaan tussen swigversakking en skuifsterkte nie. Daar is verder vasgestel dat dit nie moontlik is om te aanvaar dat daar ‘n verhouding bestaan tussen swigversakking soos vasgestel tydens die dubbele oedometer toetsing, en die verandering in volume tydens skuifsterkte toetsing nie. Daar is dus tot die slotsom gekom dat grond baie onvoorspelbaar kan wees en dat verdere navorsing na die swigversakking-verskynsel nodig is.
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Lindesay, Tamar. "The sound of the city collapsing : the changing perception and thematic role of the ruin in twentieth-century British and American poetry." Thesis, University of South Wales, 2003. https://pure.southwales.ac.uk/en/studentthesis/the-sound-of-the-city-collapsing(a371d1ec-c3ea-407a-a1f3-227d87559b3f).html.
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Kinscher, Jannes Lennart. "The analysis and interpretation of microseismicity induced by a collapsing solution mining cavity : A contribution for progress in hazard assessment of underground cavities." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0022/document.
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Pour progresser dans la compréhension des mécanismes liés aux instabilités des cavités souterraines à partir de la réponse microsismique associée, l'effondrement provoqué d'une cavité saline (~ 200 m en diamètre), créée par dissolution, a été instrumentée sur un site d’exploitation de SOLVAY à Cerville-Buissoncourt (Lorraine, France). Pendant l’expérimentation un vaste ensemble des données a été enregistré (~ 50,000 fichiers d'événements) dont la majorité (80%) est constitué d’essaims microsismiques singuliers. Cette thèse présente une analyse et une interprétation détaillée de cette base de données microsismiques grâce à l’adaptation de méthodologies de traitement originales, dont les résultats améliorent notre compréhension sur la nature de la microsismicité liée aux processus de création et d’effondrement des cavités souterraines, ainsi que sur l’évaluation de l’aléa associé. Les résultats principaux obtenus sont les suivants : les événements microsismiques sont comparables à des petits séismes tectoniques ayant des magnitudes de moment variant entre -3 et 1. (ii) L’ensemble des événements microsismiques montre un mécanisme en cisaillement (double-couple) remarquablement stable et est associé à un régime en faille inverse d’orientation NO - SE, plongeant à environ 35°– 55°. Ce phénomène est probablement lié à la présence de fractures préexistantes sur le site. (iii) L'origine des essaims microsismiques est certainement due à l'incapacité du système à créer des fractures de grandes dimensions capables de libérer des contraintes très importantes. Cela est probablement lié aux propriétés mécaniques du toit de la cavité. (iv) Les périodes d’effondrements du toit de la cavité sont associées à une dynamique de forçage systématique et montrent une réponse microsismique particulière, qui peut-être décrite par des lois statistiques. Les travaux de recherche de cette thèse confirment également, que la surveillance microsismique peut être un outil puissant pour étudier les processus d’instabilité des cavités souterraines, même avec un nombre réduit de capteurs si des outils d’analyse adaptés sont utilisésIn order to improve our understanding of hazardous underground cavities and its microseismic response, the development and collapse of a ~ 200 m wide salt solution mining cavity was monitored at Cerville-Buissoncourt in the Lorraine basin in NE France. The majority of the obtained dataset (~80%) was constituted of numerous unusual microseismic swarming events (~50.000 event files). This thesis presents innovative methods able to treat this specific microseismic data set, whose results provide new and fundamental insights into the principal characteristics of caving and collapsing related microseismicity and hazard assessment of excavated underground formations. The principal results are as follows: (i) the individual microseismic events are comparable to small natural tectonic earthquakes with moment magnitudes Mw ranging from around -3 to 1. (ii) Source mechanisms for most microseismic events are remarkable stable and demonstrate a predominant thrust faulting (double-couple) regime with faults similarly oriented NW-SE, dipping 35°-55° , what might be related to the presence of systematically arranged pre-existing fractures. (iii) The origin of microseismic swarming is suggested in the incapacity to sustain larger strains and to release larger stresses, what seems to be related to the mechanical constitution of the rock strata overlying the cavity (i.e. low strength materials). (iv) Caving and collapsing periods at the cavity roof are associated with systematic, self- reinforcing dynamics and have a distinct microseismic response, clearly observable from statistical analysis, which can be precisely described by empirical laws. The performed analysis and interpretation of the microseismicity at Cerville-Buissoncourt has shown that microseismic monitoring is a useful tool to constrain the mechanical and dynamical characteristics of an evolving and collapsing hazardous underground cavity
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Fu, Man. "A Study of Stock Market Fluctuations and their Relations to Business Conditions." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/89.
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Most research on stock prices is based on the present value model or the more general consumption-based model. When applied to real economic data, both of them are found unable to account for both the stock price level and its volatility. Three essays here attempt to both build a more realistic model, and to check whether there is still room for bubbles in explaining fluctuations in stock prices. In the second chapter, several innovations are simultaneously incorporated into the traditional present value model in order to produce more accurate model-based fundamental prices. These innovations comprise replacing with broad dividends the more narrow traditional dividends that are more commonly used, a nonlinear artificial neural network (ANN) forecasting procedure for these broad dividends instead of the more common linear forecasting models for narrow traditional dividends, and a stochastic discount rate in place of the constant discount rate. Empirical results show that the model described above predicts fundamental prices better, compared with alternative models using linear forecasting process, narrow dividends, or a constant discount factor. Nonetheless, actual prices are still largely detached from fundamental prices. The bubble-like deviations are found to coincide with business cycles. The third chapter examines possible cointegration of stock prices with fundamentals and non-fundamentals. The output gap is introduced to form the non-fundamental part of stock prices. I use a trivariate Vector Autoregression (TVAR) model and a single equation model to run cointegration tests between these three variables. Neither of the cointegration tests shows strong evidence of explosive behavior in the DJIA and S&P 500 data. Then, I applied a sup augmented Dickey-Fuller test to check for the existence of periodically collapsing bubbles in stock prices. Such bubbles are found in S&P data during the late 1990s. Employing econometric tests from the third chapter, I continue in the fourth chapter to examine whether bubbles exist in stock prices of conventional economic sectors on the New York Stock Exchange. The ‘old economy’ as a whole is not found to have bubbles. But, periodically collapsing bubbles are found in Material and Telecommunication Services sectors, and the Real Estate industry group.
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Demba, Susanne [Verfasser], Reiner [Gutachter] Brunsch, Sandra [Gutachter] Rose-Meierhöfer, and Hülya [Gutachter] Öz. "Sensor-based detection of the teat load caused by a collapsing liner using a pressure-indicating film / Susanne Demba ; Gutachter: Reiner Brunsch, Sandra Rose-Meierhöfer, Hülya Öz." Berlin : Humboldt-Universität zu Berlin, 2017. http://d-nb.info/1189429225/34.
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Sassone, Peter G. "Characterization and Avoidance of Critical Pipeline Structures in Aggressive Superscalar Processors." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7243.
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In recent years, with only small fractions of modern processors now accessible in a single cycle, computer architects constantly fight against propagation issues across the die. Unfortunately this trend continues to shift inward, and now the even most internal features of the pipeline are designed around communication, not computation. To address the inward creep of this constraint, this work focuses on the characterization of communication within the pipeline itself, architectural techniques to avoid it when possible, and layout co-design for early detection of problems.
I present work in creating a novel detection tool for common case operand movement which can rapidly characterize an applications dataflow patterns. The results produced are suitable for exploitation as a small number of patterns can describe a significant portion of modern applications.
Work on dynamic dependence collapsing takes the observations from the pattern results and shows how certain groups of operations can be dynamically grouped, avoiding unnecessary communication between individual instructions. This technique also amplifies the efficiency of pipeline data structures such as the reorder buffer, increasing both IPC and frequency.
I also identify the same sets of collapsible instructions at compile time, producing the same benefits with minimal hardware complexity. This technique is also done in a backward compatible manner as the groups are exposed by simple reordering of the binarys instructions.
I present aggressive pipelining approaches for these resources which avoids the critical timing often presumed necessary in aggressive superscalar processors. As these structures are designed for the worst case, pipelining them can produce greater frequency benefit than IPC loss. I also use the observation that the dynamic issue order for instructions in aggressive superscalar processors is predictable. Thus, a hardware mechanism is introduced for caching the wakeup order for groups of instructions efficiently. These wakeup vectors are then used to speculatively schedule instructions, avoiding the dynamic scheduling when it is not necessary.
Finally, I present a novel approach to fast and high-quality chip layout. By allowing architects to quickly evaluate what if scenarios during early high-level design, chip designs are less likely to encounter implementation problems later in the process.
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Wuester, Sebastian, and sebastian wuester@gmx net. "Classical and Quantum Field Theory of Bose-Einstein Condensates." The Australian National University. Faculty of Science, 2007. http://thesis.anu.edu.au./public/adt-ANU20070802.161045.
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We study the application of Bose-Einstein condensates (BECs) to simulations of phenomena across a number of disciplines in physics, using theoretical and computational methods.
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Collapsing condensates as created by E. Donley et al. [Nature 415, 39 (2002)]
exhibit potentially useful parallels to an inflationary universe. To enable the exploitation of this analogy, we check if current quantum field theories describe collapsing condensates quantitatively, by targeting the discrepancy between experimental and theoretical values for the time to collapse. To this end, we couple the lowest order quantum field correlation functions to the condensate wavefunction, and solve the resulting Hartree-Fock-Bogoliubov equations numerically. Complementarily, we perform stochastic truncated Wigner simulations of the collapse. Both methods also allow us to study finite temperature effects.
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We find with neither method that quantum corrections lead to a faster collapse than is predicted by Gross-Pitaevskii theory. We conclude that the discrepancy between the experimental and theoretical values of the collapse time cannot be explained by Gaussian quantum fluctuations or finite temperature effects.
Further studies are thus required before the full analogue cosmology potential of collapsing condensates can be utilised.
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As the next project, we find experimental parameter regimes in which stable three-dimensional Skyrmions can exist in a condensate. We show that their stability in a harmonic trap depends critically on scattering lengths, atom numbers, trap rotation and trap anisotropy. In particular, for the Rb87 |F=1,m_f=-1>, |F=2,m_f=1> hyperfine states, stability is sensitive to the scattering lengths at the 2% level. We find stable Skyrmions with slightly more than 2*10^6 atoms, which can be stabilised against drifting out of the trap by laser pinning.
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As a stepping stone towards Skyrmions, we propose a method for the stabilisation of a stack of parallel vortex rings in a Bose-Einstein condensate. The method makes use of a ``hollow'' laser beam containing an optical vortex, which realises an optical tunnel for the condensate. Using realistic experimental parameters, we demonstrate numerically that our method can stabilise up to 9 vortex rings.
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Finally, we focus on analogue gravity, further exploiting the analogy between flowing condensates and general relativistic curved space time. We compare several realistic setups, investigating their suitability for the observation of analogue Hawking radiation. We link our proposal of stable ring flows to analogue gravity, by studying supersonic flows in the optical tunnel. We show that long-living immobile condensate solitons generated in the tunnel exhibit sonic horizons, and discuss whether these could be employed to study extreme cases in analogue gravity.
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Beyond these, our survey indicates that for conventional analogue Hawking radiation,
simple outflow from a condensate reservoir, in effectively one dimension, has the best properties. We show with three dimensional simulations that stable sonic horizons exist under realistic conditions. However, we highlight that three-body losses impose limitations on the achievable analogue Hawking temperatures. These limitations vary between the atomic species and favour light atoms.
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Our results indicate that Bose-Einstein condensates will soon be useful for interdisciplinary studies by analogy, but also show that the experiments will be challenging.
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Wahlberg, David. "Data Reduction Methods for Deep Images." Thesis, Högskolan i Gävle, Datavetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-25473.
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Deep images for use in visual effects work during deep compositing tend to be very large. Quite often the files are larger than needed for their final purpose, which opens up an opportunity for optimizations. This research project is about finding methods for identifying redundant and excessive data use in deep images, and then approximate this data by resampling it and representing it using less data. Focus was on maintaining the final visual quality while optimizing the files so the methods can be used in a sharp production environment. While not being very successful processing geometric data, the results when optimizing volumetric data were very succesfull and over the expectations.
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Walton, Kirk S. "Sculpting: An Improved Inside-out Scheme for All Hexahedral Meshing." BYU ScholarsArchive, 2003. https://scholarsarchive.byu.edu/etd/3451.
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Generating all hexahedral meshes on arbitrary geometries has been an area of important research in recent history. Hexahedral meshes have advantages over tetrahedral meshes in structural mechanics because they provide more accurate results with fewer degrees of freedom. Many different approaches have been used to create all-hexahedral meshes. Grid-based, inside-out, or superposition meshing all refer to a similar meshing approach that is a very common mesh generation technique. Grid-based algorithms provide the ability to generate all hexahedral meshes by introducing a structured mesh that bounds the complete body modeled, marking hexahedra to define an interior and exterior mesh, manipulating the boundary region between interior and exterior regions of the structured mesh to fit the specific boundary of the body, and finally, discarding the exterior hexahedra from the given body. Such algorithms generally provide high quality meshes on the interior of the body yet distort element at the boundary in order to fill voids and match surfaces along these regions. The sculpting algorithm as presented here, addresses the difficulty in forming quality elements near boundary regions in two ways. The algorithm first finds more intelligent methods to define a structured mesh that conforms to the body to lessen large distortions to the boundary elements. Second, the algorithm uses collapsing templates to adjust the position of boundary elements to mimic the topology of the body prior to capturing the geometric boundary.
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Deruelle, Alix. "Géométrie à l'infini de certaines variétés riemanniennes non-compactes." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENM068.
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On s'intéresse à la géométrie globale et asymptotique de certaines variétés riemanniennes non compactes. Dans une première partie, on étudie la topologie et la géométrie à l'infini des variétés riemanniennes à courbure (de Ricci) positive ayant un rapport asymptotique de courbure fini. On caractérise le cas non effondré via la notion de cône asymptotique et on donne des conditions suffisantes sur le groupe fondamental pour garantir un non effondrement. La seconde partie est dédiée à l'étude des solutions de Type III du flot de Ricci à courbure positive et aux solitons gradients de Ricci expansifs (points fixes de Type III) présentant une décroissance quadratique de la courbure. On montre l'existence et l'unicité des cônes asymptotiques de tels points fixes. On donne également des conditions suffisantes de nature algébrique et géométrique pour garantir une géométrie de révolution de tels solitons. Dans une troisième partie, on caractérise la géométrie des solitons gradients de Ricci stables à courbure positive et à croissance volumique linéaire. Puis, on s'intéresse au non effondrement des variétés riemanniennes de dimension trois à courbure de Ricci positive ayant un rapport asymptotique de courbure finiWe study the global and asymptotic geometry of non-compact Riemannian manifolds. First, we study the topology and geometry at infinity of Riemannian manifolds with nonnegative (Ricci) curvature and finite asymptotic curvature ratio. We focus on the non-collapsed case with the help of asymptotic cones and we give sufficient conditions on the fundamental group to guarantee non-collapsing. The second part is dedicated to the study of (non-negatively curved) Type III Ricci flow solutions. We mainly analyze the asymptotic geometry of Type III self-similar solutions (expanding gradient Ricci soliton) with finite asymptotic curvature ratio. We prove the existence and uniqueness of their asymptotic cones. We also give algebraic and geometric sufficient conditions to guarantee rotational symmetry of such metrics. In the last part, we characterize the geometry of steady gradient Ricci solitons with nonnegative sectional curvature and linear volume growth. Finally, we study the non-collapsing of three dimensional Riemannian manifold with nonnegative Ricci curvature and finite asymptotic curvature ratio