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Derived Invariance of the Tamarkin-Tsygan Calculus of an Associative Algebra / Invariance dérivée du calcul de Tamarkin-Tsygan d'une algèbre associativeArmenta Armenta, Marco 10 September 2019 (has links)
Dans cette thèse nous démontrons que le calcul de Tamarkin-Tsygan d’une algèbre `associative de dimension finie sur un corps est un invariant dérivé. En d’autres mots, le résultat principal de ce travail est le suivant : une équivalence dérivée entre deux algèbres de dimension finie sur un corps induit un isomorphisme entre l’homologie de Hochschild et la cohomologie de Hochschild qui respecte simultanément le cup produit, le cap produit, le crochet de Gerstenhaber et la ´différentielle de Connes. / In this thesis we prove that the Tamarkin-Tsygan calculus of a finite dimensionalassociative algebra over a field is a derived invariant. In other words, the mainresult of this work goes as follows: a derived equivalence between two finite dimensional associative algebras over a field induces an isomorphism betweenHochschild homology and Hochschild cohomology that respects simultaneouslythe cup product, the cap product, the Gerstenhaber bracket and the Connes differential.
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On the Casson-Walker invariant of 3-manifolds with genus one open book decompositions / 種数1の開本分解を持つ3次元多様体のCasson-Walker不変量についてMochizuki, Atsushi 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21545号 / 理博第4452号 / 新制||理||1639(附属図書館) / 京都大学大学院理学研究科数学・数理解析専攻 / (主査)教授 大槻 知忠, 教授 向井 茂, 教授 小野 薫 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
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The analysis and co-design of weakly-consistent applications / L'analyse et co-design des applications faiblement-cohérentNajafzadeh, Mahsa 22 April 2016 (has links)
Afin d'assurer disponibilité et réactivité, de nombreux systèmes distribués reposent sur des bases de données répliquées qui maintiennent des copies (répliques) des données sur différents serveurs. la cohérence constitue un défi important dans la mise en oeuvre des bases de données répliquées. les concepteurs de bases de données repliquées doivent faire un choix difficile entre une cohérence forte, qui guarantit une large gamme d'invariants applicatifs, mais qui est lente et fragile, et une réplication asynchrone, qui assure un bon niveau de disponibilité et de réactivité, mais laisse le programmeur face à de possibles anomalies liées à la concurrence.pour résoudre ce dilemme, des bases de données commerciales et recherche fournissent une cohérence hybride qui permet au programmeur d'exiger une cohérence forte pour certaines opérations, et d'ainsi permettre une synchronisation.cette thèse étudie l'analyse et la mise en oeuvre d'une application et de la cohérence associée, de manière à assurer les invariants de cette application avec un minimum d'exigences de cohérence. les trois principales contributions de cette thèse sont: 1) nous proposons le premier outil d'analyse statique destiné à prouver la validité d'invariants d'applications de base de données à modèle de cohérence hybride. 2) nous présentons la mise en application de notre outil d'analyse dans le cadre de la conception d'un système de fichiers dont la sémantique permet un comportement similaire à posix et à un coût résonable. 3)nous proposons un ensemble de patterns utiles, susceptibles d'aider les développeurs d'application dans l'implémentation d'invariants les plus communs. / Distributed databases take advantage of replication to bring data close to the client, and to always be available. the primary challenge for such databases is to ensure consistency. recent research provide hybrid consistency models that allow the database supports asynchronous updates by default, but synchronisation is available upon request. to help programmers exploit the hybrid consistency model, we propose a set of useful patterns,proof rules, and tool for proving integrity invariants of applications. in the first part, we study a sound proof rule that enables programmers to check whether the operations of a given application semantics maintain the application invariants under a given amount of parallelism. we have developed a smt-based tool that automates this proof, and verified several example applications using the tool. in the second part, we apply the above methodology to the design of a replicated file system.the main invariant is that the directory structure forms a tree. we study three alternative semantics for the file system. each exposes a different amount of parallelism, and different anomalies. using our tool-assisted rules, we check whether a specific file system semantics maintains the tree invariant, and derive an appropriate consistency protocol. in the third part of this thesis, we present three classes of invariants: equivalence, partial order, and single-item generic. each places some constraints over the state. each of these classes maps to a different storage-layer consistency property: respectively, atomicity, causal ordering, or total ordering.
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Comparing Invariants of 3-Manifolds Derived from Hopf AlgebrasSequin, Matthew James 27 June 2012 (has links)
No description available.
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Dynamic Invariant Generation for Concurrent ProgramsChattopadhyay, Arijit 23 June 2014 (has links)
We propose a fully automated and dynamic method for generating likely invariants from multithreaded programs and then leveraging these invariants to infer atomic regions and diagnose concurrency errors in the software code. Although existing methods for dynamic invariant generation perform reasonably well on sequential programs, for multithreaded programs, their effectiveness often reduces dramatically in terms of both the number of invariants that they can generate and the likelihood of them being true invariants. We solve this problem by developing a new dynamic invariant generator, which consists of a new LLVM based code instrumentation tool, an INSPECT based thread interleaving explorer, and a customized inference engine inside Daikon. We have evaluated the resulting system on public domain multithreaded C/C++ benchmarks. Our experiments show that the new method is effective in generating high-quality invariants. Furthermore, the state and transition invariants generated by our new method have been proved useful both in error diagnosis and in identifying likely atomic regions in the concurrent software code. / Master of Science
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Scene Analysis Using Scale Invariant Feature Extraction and Probabilistic ModelingShen, Yao 08 1900 (has links)
Conventional pattern recognition systems have two components: feature analysis and pattern classification. For any object in an image, features could be considered as the major characteristic of the object either for object recognition or object tracking purpose. Features extracted from a training image, can be used to identify the object when attempting to locate the object in a test image containing many other objects. To perform reliable scene analysis, it is important that the features extracted from the training image are detectable even under changes in image scale, noise and illumination. Scale invariant feature has wide applications such as image classification, object recognition and object tracking in the image processing area. In this thesis, color feature and SIFT (scale invariant feature transform) are considered to be scale invariant feature. The classification, recognition and tracking result were evaluated with novel evaluation criterion and compared with some existing methods. I also studied different types of scale invariant feature for the purpose of solving scene analysis problems. I propose probabilistic models as the foundation of analysis scene scenario of images. In order to differential the content of image, I develop novel algorithms for the adaptive combination for multiple features extracted from images. I demonstrate the performance of the developed algorithm on several scene analysis tasks, including object tracking, video stabilization, medical video segmentation and scene classification.
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An investigation into the regulatory capacity of invariant natural killer T (iNKT) cells during the innate and adaptive immune response to influenza infectionMcEwen-Smith, Rosanna Mary January 2014 (has links)
Influenza A virus (IAV) infection is a highly contagious respiratory disease, which can cause substantial morbidity and occasionally death. Invariant natural killer T (iNKT) cells, a subset of CD1d-restricted T lymphocytes, have been identified as important modulators of immunity, mediating both pro- and anti-inflammatory responses. We show that iNKTs play an important role for the generation of protective innate and adaptive immune responses to IAV, and enhance heterotypic immunity to influenza virus following vaccination with a novel pseudotyped virus, S-FLU, which lacks HA expression. iNKT-deficient mice (Jα18<sup>-/-</sup>) showed increased susceptibility and lung pathology following IAV infection, which correlated with an exaggerated accumulation of inflammatory monocytes and neutrophils in the lung. Consistent with these findings, we demonstrated in IAV-infected CD1d<sup>-/-</sup>:CD1d<sup>+/+</sup> mixed bone marrow chimeric mice, that the lack of CD1d expression on myeloid cells purified from the lungs of IAV-infected mice significantly increased expression of genes linked to cell activation, survival and polarisation between pro- and antiinflammatory responses. We extended these results by examining the role of chemokine signalling during IAV infection, and identified a novel role for fractalkine (CX3CL1) and its receptor (CX3CR1) in innate immune cell recruitment. The use of CX3CR1-iNKT cell double knockout mice revealed that, although upregulated in Jα18<sup>-/-</sup> mice, CX3CR1-CX3CL1 signalling is not required for cell migration during exacerbated IAV-responses. Finally, we showed that iNKT-deficient mice displayed reduced longevity of peripheral IAVspecific CD8<sup>+</sup> T cells following S-FLU vaccination, compared with wild-type mice. S-FLU vaccination protected mice following 5 day heterotypic challenge, however vaccinated mice exhibited reduced viral clearance, and importantly a significant reduction in IAV specific memory T cell response, suggesting a possible role of iNKT cells during T cell priming in modulating the lifespan of antigen-specific T cell responses. Although additional experiments are warranted, these results suggest that harnessing iNKT cells should be considered to modulate the innate and adaptive immune response to optimise heterotypic vaccine design and for therapeutic intervention against acute influenza infection.
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Analytic Torsion, the Eta Invariant, and Closed Differential Forms on Spaces of MetricsAndreae, Phillip January 2016 (has links)
<p>The central idea of this dissertation is to interpret certain invariants constructed from Laplace spectral data on a compact Riemannian manifold as regularized integrals of closed differential forms on the space of Riemannian metrics, or more generally on a space of metrics on a vector bundle. We apply this idea to both the Ray-Singer analytic torsion</p><p>and the eta invariant, explaining their dependence on the metric used to define them with a Stokes' theorem argument. We also introduce analytic multi-torsion, a generalization of analytic torsion, in the context of certain manifolds with local product structure; we prove that it is metric independent in a suitable sense.</p> / Dissertation
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Symmetry solutions and conservation laws for some partial differential equations in fluid mechanicsNaz, Rehana 26 May 2009 (has links)
ABSTRACT
In jet problems the conserved quantity plays a central role in the solution
process. The conserved quantities for laminar jets have been established either
from physical arguments or by integrating Prandtl's momentum boundary
layer equation across the jet and using the boundary conditions and the
continuity equation. This method of deriving conserved quantities is not
entirely systematic and in problems such as the wall jet requires considerable
mathematical and physical insight.
A systematic way to derive the conserved quantities for jet °ows using
conservation laws is presented in this dissertation. Two-dimensional, ra-
dial and axisymmetric °ows are considered and conserved quantities for
liquid, free and wall jets for each type of °ow are derived. The jet °ows
are described by Prandtl's momentum boundary layer equation and the
continuity equation. The stream function transforms Prandtl's momentum
boundary layer equation and the continuity equation into a single third-
order partial di®erential equation for the stream function. The multiplier
approach is used to derive conserved vectors for the system as well as
for the third-order partial di®erential equation for the stream function for
each jet °ow. The liquid jet, the free jet and the wall jet satisfy the same
partial di®erential equations but the boundary conditions for each jet are
di®erent. The conserved vectors depend only on the partial di®erential
equations. The derivation of the conserved quantity depends on the boundary
conditions as well as on the di®erential equations. The boundary condi-
tions therefore determine which conserved vector is associated with which
jet. By integrating the corresponding conservation laws across the jet and
imposing the boundary conditions, conserved quantities are derived. This
approach gives a uni¯ed treatment to the derivation of conserved quantities for jet °ows and may lead to a new classi¯cation of jets through conserved vectors.
The conservation laws for second order scalar partial di®erential equations
and systems of partial di®erential equations which occur in °uid mechanics
are constructed using di®erent approaches. The direct method, Noether's
theorem, the characteristic method, the variational derivative method (mul-
tiplier approach) for arbitrary functions as well as on the solution space,
symmetry conditions on the conserved quantities, the direct construction
formula approach, the partial Noether approach and the Noether approach for
the equation and its adjoint are discussed and explained with the help of an
illustrative example. The conservation laws for the non-linear di®usion equa-
tion for the spreading of an axisymmetric thin liquid drop, the system of two
partial di®erential equations governing °ow in the laminar two-dimensional
jet and the system of two partial di®erential equations governing °ow in the
laminar radial jet are discussed via these approaches.
The group invariant solutions for the system of equations governing °ow in two-dimensional and radial free jets are derived. It is shown that the group
invariant solution and similarity solution are the same.
The similarity solution to Prandtl's boundary layer equations for two-
dimensional and radial °ows with vanishing or constant mainstream velocity
gives rise to a third-order ordinary di®erential equation which depends on a
parameter. For speci¯c values of the parameter the symmetry solutions for
the third-order ordinary di®erential equation are constructed. The invariant solutions of the third-order ordinary di®erential equation are also derived.
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Conway's Link Polynomial: a Generalization of the Classic Alexander's Knot PolynomialWoodard, Mary Kay 12 1900 (has links)
The problem under consideration is that of determining a simple and effective invariant of knots. To this end, the Conway polynomial is defined as a generalization of Alexander's original knot polynomial. It is noted, however, that the Conway polynomial is not a complete invariant. If two knots are equivalent, as defined in this investigation, then they receive identical polynomials. Yet, if two knots have identical polynomials, no information about their equivalence may be obtained. To define the Conway polynomial, the Axioms for Computation are given and many examples of their use are included. A major result of this investigation is the proof of topological invariance of these polynomials and the proof that the axioms are sufficient for the calculation of the knot polynomial for any given knot or link.
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