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Tiger, Norkvist Axel. "Morphisms of real calculi from a geometric and algebraic perspective." Licentiate thesis, Linköpings universitet, Algebra, geometri och diskret matematik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-175740.
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Noncommutative geometry has over the past four of decades grown into a rich field of study. Novel ideas and concepts are rapidly being developed, and a notable application of the theory outside of pure mathematics is quantum theory. This thesis will focus on a derivation-based approach to noncommutative geometry using the framework of real calculi, which is a rather direct approach to the subject. Due to their direct nature, real calculi are useful when studying classical concepts in Riemannian geometry and how they may be generalized to a noncommutative setting. This thesis aims to shed light on algebraic aspects of real calculi by introducing a concept of morphisms of real calculi, which enables the study of real calculi on a structural level. In particular, real calculi over matrix algebras are discussed both from an algebraic and a geometric perspective.Morphisms are also interpreted geometrically, giving a way to develop a noncommutative theory of embeddings. As an example, the noncommutative torus is minimally embedded into the noncommutative 3-sphere.<br>Ickekommutativ geometri har under de senaste fyra decennierna blivit ett etablerat forskningsområde inom matematiken. Nya idéer och koncept utvecklas i snabb takt, och en viktig fysikalisk tillämpning av teorin är inom kvantteorin. Denna avhandling kommer att fokusera på ett derivationsbaserat tillvägagångssätt inom ickekommutativ geometri där ramverket real calculi används, vilket är ett relativt direkt sätt att studera ämnet på. Eftersom analogin mellan real calculi och klassisk Riemanngeometri är intuitivt klar så är real calculi användbara när man undersöker hur klassiska koncept inom Riemanngeometri kan generaliseras till en ickekommutativ kontext. Denna avhandling ämnar att klargöra vissa algebraiska aspekter av real calculi genom att introducera morfismer för dessa, vilket möjliggör studiet av real calculi på en strukturell nivå. I synnerhet diskuteras real calculi över matrisalgebror från både ett algebraiskt och ett geometriskt perspektiv. Morfismer tolkas även geometriskt, vilket leder till en ickekommutativ teori för inbäddningar. Som ett exempel blir den ickekommutativa torusen minimalt inbäddad i den ickekommutativa 3-sfären.
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Smith, D. J. "Homology modules in projective space." Thesis, University of East Anglia, 2007. https://ueaeprints.uea.ac.uk/38270/.
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Ahmed, Iftikhar. "Projective modules of group rings over quadratic number fields." Thesis, Durham University, 1994. http://etheses.dur.ac.uk/5669/.
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Let K be a quadratic number field, Ok its ring of integers, and G a cyclic group of order prime p. In this thesis, we study the kernel group D(O(_K)G) and obtain a number of results concerning its order and structure. For K imaginary, we also investigate the subset R(O(_k)G) of the locally free class group CI(O(_k)G) consisting of classes which occur as rings of integers of tame extensions of K with Galois group isomorphic to G. We calculate R(O(_k)G) under a variety of conditions and obtain, for an arbitrary tame extension L o( K with group G, invariants which determine the class of O(_L) in R(O(_k)G).
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Kalaycioglu, Selin. "Computing the projective indecomposable modules of large finite groups." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/193610.
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Let G be a finite group and F be a finite field. A projective indecomposable FG- module is an indecomposable direct summand of the group algebra FG. Computing the projective indecomposable modules of large finite groups has been always a challenging problem due to the large sizes of the representations of these groups. This dissertation describes a new algorithm for constructing the projective indecomposable modules of large finite groups. This algorithm uses the condensation techniques as described in [12]. The power of the algorithm will be illustrated by the examples of the socle series of all projective indecomposable modules of the sporadic simple Mathieu group M₂₄ and the simple alternating group A₁₂ in characteristic 2.
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O'Shea, S. "Stably free modules over virtually free groups." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1383774/.
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We study stably free modules over various group rings Z[G], using the method of Milnor patching. In particular, we construct innite sets of stably free modules of rank one over various rings. Let Fn denote the free group on n generators. The two classes of group rings under consideration are: (i) Z[GxFn], where G is nite nilpotent and of non square-free order, and n > 2; (ii) Z[Q(12m) x C1], where Q(12m) is the binary polyhedral group of order 12m. The modules in question are constructed as pullbacks arising from bre square decompositions of the group rings. We also study the D(2)-problem of low-dimensional topology. We give an affirmative answer to the D(2)-problem for the dihedral group of order 4n, assuming the group ring Z[D4n] satisfies torsion free cancellation. By results of Swan, Endo, and Miyata, this happens for a number of small primes n. Johnson has shown that the groups D4n+2 satisfy the D(2)-property, but his result relies on the fact that D4n+2 has periodic cohomology, a property not shared by D4n. This forces us to introduce the torsion free cancellation hypothesis, and to explicitly realize the group of k-invariants (Z/4n).
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Hilburn, Justin. "GKZ Hypergeometric Systems and Projective Modules in Hypertoric Category O." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20456.
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In this thesis I show that indecomposable projective and tilting modules in hypertoric category O are obtained by applying a variant of the geometric Jacquet functor of Emerton, Nadler, and Vilonen to certain Gel'fand-Kapranov-Zelevinsky hypergeometric systems. This proves the abelian case of a conjecture of Bullimore, Gaiotto, Dimofte, and Hilburn on the behavior of generic Dirichlet boundary conditions in 3d N=4 SUSY gauge theories.
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Strouthos, I. "Stably free modules over group rings." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1325632/.
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We study finitely generated stably free modules over group rings associated to particular groups, primarily using Milnor’s construction of projective modules over rings and Quillen’s Patching Theorem. For an odd prime number q, we study the stably free module category of the group ring of the dihedral group of order 2q over the ring of integer coefficient polynomials in one variable. We show that, over this group ring, every stably free module is free if every stably free module is free over a particular localisation of a cyclic algebra over the ring of algebraic integers corresponding to the prime q. Using this result, we show that every stably free module is free over the group ring of the dihedral group of order 6 over the ring of integer coefficient polynomials, and we later extend this result to all dihedral groups of order 2q. Furthermore, we consider a class of projective modules, which we regard as locally free, in a certain precise sense, and which are related to stably free modules under certain conditions. We show that, over the integral group ring of the direct product of a quaternion group of order 8 and the infinite cyclic group, there are infinitely many such locally free modules of rank 1. In addition, we show that, over the algebra of integer coefficient quaternions, every projective module is free. Finally this thesis includes a treatment of resolutions of indecomposable modules over the integral group ring of the dihedral group of order 6. By studying the irreducible integral representations of this dihedral group, we construct certain resolutions for which there is a notion of duality and diagonalisability in the constituent homomorphisms, via the syzygy operator.
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Ben, Hamouda-Guichoux Fabrice. "Diverse modules and zero-knowledge." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEE022/document.
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Les smooth (ou universal) projective hash functions ont été introduites par Cramer et Shoup, à Eurocrypt'02, comme un outil pour construire des schémas de chiffrement efficaces et sûrs contre les attaques à chiffrés choisis. Depuis, elles ont trouvé de nombreuses applications, notamment pour la construction de schémas d'authentification par mot de passe, d'oblivious transfer, de signatures en blanc, et de preuves à divulgation nulle de connaissance. Elles peuvent êtres vues comme des preuves implicites d'appartenance à certains langages. Un problème important est de caractériser pour quels langages de telles fonctions existent.Dans cette thèse, nous avançons dans la résolution de ce problème en proposant la notion de diverse modules. Un diverse module est une représentation d'un langage, comme un sous-module d'un module plus grand, un module étant un espace vectoriel sur un anneau. À n'importe quel diverse module est associée une smooth projective hash function pour le même langage. Par ailleurs, presque toutes les smooth projective hash functions actuelles sont construites de cette manière.Mais les diverse modules sont aussi intéressants en eux-mêmes. Grâce à leur structure algébrique, nous montrons qu'ils peuvent facilement être combinés pour permettre de nouvelles applications, comme les preuves implicites à divulgation nulle de connaissance (une alternative légère aux preuves non-interactives à divulgation nulle de connaissance), ainsi que des preuves non-interactives à divulgation nulle de connaissance et one-time simulation-sound très efficaces pour les langages linéaires sur les groupes cycliques<br>Smooth (or universal) projective hash functions were first introduced by Cramer and Shoup, at Eurocrypt'02, as a tool to construct efficient encryption schemes, indistinguishable under chosen-ciphertext attacks. Since then, they have found many other applications, including password-authenticated key exchange, oblivious transfer, blind signatures, and zero-knowledge arguments. They can be seen as implicit proofs of membership for certain languages. An important question is to characterize which languages they can handle.In this thesis, we make a step forward towards this goal, by introducing diverse modules. A diverse module is a representation of a language, as a submodule of a larger module, where a module is essentially a vector space over a ring. Any diverse module directly yields a smooth projective hash function for the corresponding language, and almost all the known smooth projective hash functions are constructed this way.Diverse modules are also valuable in their own right. Thanks to their algebraic structural properties, we show that they can be easily combined to provide new applications related to zero-knowledge notions, such as implicit zero-knowledge arguments (a lightweight alternative to non-interactive zero-knowledge arguments), and very efficient one-time simulation-sound (quasi-adaptive) non-interactive zero-knowledge arguments for linear languages over cyclic groups
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Kong, Maynard. "Characteristic classes of modules." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/97347.
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In this paper we have developed a general theory of characteristic classes of modules. To a given invariant map defined on a Lie algebra, we associate a cohomology class by using the curvature form of a certain kind of connections. Here we present a very simple proof of the invariance theorem (Theorem 12), which states that equivalent connections give rise to the same characteristic class. We have used those invariant maps of {9} to define Chern classes of projective modules and we have derived their basic properties. It might be interesting to observe that this theory could be applied to define characteristic classes of bilinear maps. In particular, the Euler classes of {6} can be obtained in this way.
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Kremer, Raymond Edward. "HOMOLOGICAL ALGEBRA WITH FILTERED MODULES." UKnowledge, 2014. http://uknowledge.uky.edu/math_etds/18.
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Classical homological algebra is done in a category of modules beginning with the study of projective and injective modules. This dissertation investigates analogous notions of projectivity and injectivity in a category of filtered modules. This category is similar to one studied by Sjödin, Nǎstǎsescu, and Van Oystaeyen. In particular, projective and injective objects with respect to the restricted class of strict morphisms are defined and characterized. Additionally, an analogue to the injective envelope is discussed with examples showing how this differs from the usual notion of an injective envelope.
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Beaudet, Louis. "Sur les modules de dimension projective infinie sur les algèbres inclinées-amassées." Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5415.
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Résumé : L’objectif principal de cette thèse est d’approfondir l’étude des modules de dimension projective infinie sur les algèbres inclinées-amassées. Dans un premier temps, nous bornerons la fonction [o barré] d’Igusa-Todorov dans le cadre des algèbres inclinées-amassées de type An et ~ An. Subséquemment, nous donnerons une preuve combinatoire de la périodicité des premiers syzygies des modules de corde et de bande sur de telles algèbres. Grâce à cette périodicité, nous serons en mesure de borner supérieurement la [o barré]-dimension d’Igusa-Todorov. Nous caractériserons, dans une deuxième partie, les modules de dimension projective infinie de l’algèbre d’endomorphismes End C (T), où C’est une catégorie triangulée possédant un objet T maximal 1-orthogonal. Nous montrerons qu’un End C(T)-module M est de dimension projective infinie si et seulement si son idéal de factorisation IM End C(T[1]) est non nul. De plus, inspirés par les travaux sur les hamacs de Brenner, Ringel et Vos- sieck ([7], [26]), nous décrirons et regrouperons les modules de dimension projective infinie en un nouvel ensemble, appelé balançoire, particulièrement localisable dans le carquois d’Auslander-Reiten de End C(T). // Abstract : The writing of this thesis was guided by a single main idea; to go deeper in the study of infinite projective dimension modules on cluster-tilted algebras. At first, we will find an upper bound for the function [o barré] of Igusa-Todorov in the framework of the cluster-tilted algebras of type An and ~ An. Subsequently, we will give a combinatorial proof of the periodicity of the first syzygy of a string and a band module on such algebras. With this periodicity, we will be able to bound the [o barré]-dimension of Igusa-Todorov. In the second part, we will characterize infinite projective dimension modules by explaining their exact positions in the Auslander-Reiten quiver of the algebra End C(T), where C is any triangulated category and T a 1-maximal orthogonal object of C. We show that an End C(T) -module M is of infinite projective dimension if and only if its factorization ideal IM End C(T [1]) is nonzero. In addition, inspired by the works on hammocks by Brenner, Ringel and Vossieck ([7], [26]), we will describe and regroup in a new set, called a swing, the modules of infinite projective dimension especially localizable in the quiver of Auslander-Reiten of End C(T). [Symboles non conformes].
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Goerl, Lee W. "Sheaves of differential operators and D-modules over non-commutative projective spaces." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34515.
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Doctor of Philosophy<br>Department of Mathematics<br>Zongzhu Lin<br>For a scheme, let D be the sheaf of differential operators, assigning to any open subscheme it’s ring of differential operators. The study of D-modules advances their theory independently, but pervades many other areas of modern mathematics as well. Most notably, the theory provided a framework to solve Hilbert’s 21-st problem, and to develop the Riemann-Hilbert correspondence, and eventually led to the resolution of the Kazhdan-Lustig conjecture in representation theory. For an affine patch of the scheme having dimension n, the sheaf will assign the n-th Weyl algebra. In [1], Hayashi develops the quantized Weyl algebra, a deformation of this algebra, and in [2] Lunts and Rosenberg develop versions of β and quantum differential operators for a graded non-commutative algebra. Iyer and McCune compute in [3] the ring of these quantum differential operators of Lunts and Rosenberg over the polynomial algebra in n-variables, or, over affine n-space. In [4], Bischof examines how a reconciliation of the β deformation in [2] and a 2-cocycle deformation of the graded algebra influence the category of these quantum D-modules, and considers some localizations. One naturally wonders about the category of modules for these quantum differential operators on a non-commutative space; about it’s objects and it’s structure. With the aim of future study in non-commutative grassmannians and flag varieties, of U[subscript]q(sl[subscript]n), for example, we consider a non-commutative projective space glued together from a covering of 2-cocycle deformed polynomial rings, as proposed in [5] and [4]. We determine when there exists a deformed polynomial ring from which we can obtain this covering, and the category of quasi-coherent sheaves can be realized via the categorical Proj construction. With a guiding hand from Rosenberg’s [5] we develop a general ring structure for containing these quantum differential operators on polynomial algebras. Finally, towards the goal of defining holonomic quantum D-modules, we consider the GK-dimension of the corresponding associated graded algebra for the purpose of determining the dimension of what might be considered the singular support for a quantum D-module.
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Bardelang, Reinfried Gunther. "Endomorphisms of free modules over local rings." Thesis, University of York, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282269.
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Kamali, P. "Stably free modules over innite group algebras." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/192838/.
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We study finitely generated stably-free modules over infinite integral group algebras by using the language of cyclic algebras and relating it to well-known results in K-theory. For G a free or free abelian group and Q8n, the quaternionic group of order 8n, we show that there exist infinitely many isomorphically distinct stably-free modules of rank 1 over the integral group algebra of the group \Gamma = Q8n x G whenever n admits an odd divisor. This result implies that the stable class of the augmentation ideal \Omega{_1}Z displays infinite splitting at minimal level whenever G is the free abelian group on at least 2 generators. This is of relevance to low dimensional topology, in particular when computing homotopy modules of a cell complex with fundamental group \Gamma.
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Bartley, Michael George. "The axiom : 'all free groups are projective in Ab(E)'." Thesis, University of Bristol, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330322.
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Gargoubi, Hichem. "Modules des opérateurs différentiels sur la droite : géométrie projective et cohomologie de Gelfand-Fuks." Aix-Marseille 1, 1997. http://www.theses.fr/1997AIX11079.
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Nous etudions l'espace d#k des operateurs differentiels lineaires d'ordre quelconque k sur r : a = a#k(x)d#k/dx#k + + a#0(x), comme module sur le groupe diff(r) des diffeomorphismes de la droite et sur l'algebre de lie vect(r) des champs de vecteurs sur la droite. Il existe sur d#k une famille naturelle a deux parametres de diff(r)- et vect(r)-actions. Les diff(r)-modules d#k##,# sont definis en considerant respectivement les arguments des operateurs differentiels et leurs images comme des densites tensorielles de degres et : a : f# f#. Le resultat principal de cette these est la classification des modules d#k##,#. La methode utilisee est basee sur la cohomologie de gelfand-fuks de vect(r) a coefficients dans l'espace hom(f#, f#). Les modules des operateurs differentiels sont lies a la geometrie differentielle projective. Nous trouvons une serie de classes de cohomologie non triviales dans h#1 (sl#2(r) ; hom(f#n#/#2, f n/2 1)) qui apparaissent en considerant la restriction des vect(r)-modules des operateurs differentiels a la sous-algebre des symetries projectives sl#2(r) vect(r). Les resultats principaux de ce travail sont les theoremes 1 (p. 12), 5. 1, 5. 2, 5. 3 et 5. 4 (pages 26-28).
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Le, Gros Giovanna. "Minimal approximations for cotorsion pairs generated by modules of projective dimension at most one over commutative rings." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3423180.
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In this thesis we study cotorsion pairs (A, B) generated by classes of R-modules of projective dimension at most one. We are interested in when these cotorsion pairs provide covers or envelopes over commutative rings. More precisely, we investigate Enochs' Conjecture in this setting. That is, for a class A contained in the class of modules of projective dimension at most one, denoted P_1, we investigate the question of whether A is covering necessarily implies that A is closed under direct limits. Additionally, under certain restrictions we characterise the rings which satisfy this property. To this end, there were two cases to consider: when the cotorsion pair is of finite type and when it is not of finite type.
For the case that the cotorsion pair (P_1, B) is not (necessarily) of finite type, we show that over a semihereditary ring R, if P_1 is covering it must be closed under direct limits. This gives an example of a cotorsion pair not of finite type which satisfies Enochs' Conjecture.
The next part of the thesis is dedicated toward cotorsion pairs of finite type, specifically the 1-tilting cotorsion pairs over commutative rings. We rely heavily on work of Hrbek who characterises these cotorsion pairs over commutative rings, as well as work of Positselski and Bazzoni-Positselski in their work on contramodules.
We consider the case of a 1-tilting cotorsion pair (A, T) over a commutative ring with an associated Gabriel topology G, and begin by investigating when T is an enveloping class. We find that if T is enveloping, then the associated Gabriel topology must arise from a perfect localisation. That is, G must arise from a flat ring epimorphism from R to R_G, where R_G is the ring of quotients of R with respect to G. Furthermore, if G arises from a perfect localisation, T is enveloping in Mod-R if and only if the projective dimension of R_G is less than or equal to one and R/J is a perfect ring for every ideal J in G if and only if the projective dimension of R_G is less than or equal to one and the topological ring End(R_G/R) is pro-perfect.
Next, we consider the case that A is a covering class, and we prove that A is covering in Mod-R if and only if the projective dimension of R_G is less than or equal to one and both the localisation R_G is a perfect ring and R/J is a perfect ring for every J in G.
Additionally, we study general cotorsion pairs, as well as conditions for an approximation to be a minimal approximation. Moreover, we consider a hereditary cotorsion pair and show that if it provides covers it must provide envelopes.<br>In questa tesi studiamo le coppie di cotorsione (A, B) generate da classi di R-moduli di dimensione proiettiva al più uno. Siamo interessati nel caso in cui queste coppie di cotorsione ammettano ricoprimenti o inviluppi su anelli commutativi. Più precisamente, indaghiamo la congettura di Enochs per A. Cioè, per A contenuta nella classe P_1, che denota la classe di R-moduli di dimensione proiettiva al più uno, cerchiamo di capire se per A una classe ricoprente allora necessariamente implica che A è chiusa per limiti diretti. In più, con certe restrizioni, descriviamo gli anelli che soddisfano questa proprietà. Ci sono due casi da considerare: il caso di coppia di cotorsione di tipo finito e il caso non di tipo finito.
Quando la coppia di cotorsione non è (necessariamente) di tipo finito, dimostriamo che per un anello commutativo semiereditario R, se P_1 è una classe ricoprente, deve essere chiusa per limiti diretti. Questo ci da un esempio di una coppia di cotorsione che non è di tipo finito che soddisfa la congettura di Enochs.
Successivamente, analizziamo le coppie di cotorsione di tipo finito. Specificamente, le coppie di cotorsione 1-tilting su anelli commutativi. A questo scopo sono indispensabili il lavoro di Hrbek, che caratterizza tali coppie di cotorsione su anelli commutativi, e il lavoro di Positselski e Bazzoni-Positselski nel loro lavoro sui contramoduli.
Consideriamo il caso di una coppia di cotorsione 1-tilting (A, T) su un anello commutativo con una topologia di Gabriel associata G, e studiamo quando (A, T) ammette inviluppi. Troviamo che se T ammette inviluppi, G è una topologia di Gabriel perfetta. Cioè, G viene da un epimorfismo piatto di anelli da R a R_G dove R_G è la localizzazione di R rispetto a G. Inoltre, se G è una topologia di Gabriel perfetta, T ammette inviluppi se e solo se R_G ha dimensione proiettiva al più uno e R/J è un anello perfetto per tutti gli ideali J in G se e solo se R_G ha dimensione proiettiva al più uno e l'anello topologico End(R_G/R) è pro-perfetto. Poi consideriamo il caso in cui A è ricoprente. Dimostriamo che A è ricoprente in Mod-R se e solo se R_G ha dimensione proiettiva al più uno e R_G è un anello perfetto e R/J è perfetto per ogni J in G.
In aggiunta, studiamo coppie di cotorsione in generale e studiamo condizioni sufficienti affinchè una approssimazione sia minimale. Inoltre, consideriamo una coppia di cotorsione ereditaria e dimostriamo che se ammette ricoprimenti deve ammettere inviluppi.
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Agoston, Istvan Carleton University Dissertation Mathematics. "On the rank of torsion-free modules over tame hereditary algebras." Ottawa, 1990.
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Iritani, Hiroshi. "Quantum D-modules and equivariant Floer theory for free loop spaces." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/145144.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(理学)<br>甲第11379号<br>理博第2937号<br>新制||理||1439(附属図書館)<br>23022<br>UT51-2005-D130<br>京都大学大学院理学研究科数学･数理解析専攻<br>(主査)教授 中島 啓, 教授 深谷 賢治, 教授 河野 明<br>学位規則第4条第1項該当
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Benchoufi, Mehdi. "Théorie microlocale des faisceaux pour la transformation Radon." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS475.
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Le sujet de cette thèse est une approche microlocale de la transformation de Radon. Il s’agit d’appliquer à la dualité projective complexe et réelle les techniques initiées dans l’article fondateur de Sato-Kashiwara-Kawai de 1972 et de retrouver, reformuler, améliorer des travaux d’analyse plus classiques sur ce sujet, en particulier ceux de G. Henkin ou S. Gindikin. La dualité projective vue sous l’angle microlocal et faisceautique est apparue pour la première fois dans un travail important de J-L. Brylinski sur les faisceaux pervers, travail repris ensuite par D’Agnolo et Schapira dans le cadre des D-modules. Notre travail est de reprendre systématiquement cette étude avec les nouveaux outils de la théorie microlocale des faisceaux (théorie qui n’existait pas à l’époque de SKK72). Ce travail se compose essentiellement de deux parties. Dans la première, nous commençons par rappeler dans un cadre général la construction des transformations canoniques quantifiées, sous l’hypothèse de l’existence d’une section simple non-dégénérée (introduite sous un autre nom par J. Leray). Cette construction n’avait jamais été faite dans un cadre global hors du cas projectif. Nous montrons alors que ces transformations commutent à l’action des opérateurs microdifferentiels. Il s’agit là d’un résultat fondamental sans qu’aucune preuve consistante n’existe dans la littérature, ce résultat étant plus ou moins sous-entendu dans SKK72. La deuxième partie de la thèse traite des applications à la transformation de Radon “clas-sique”. L’idée de base est que cette transformation échange support des hyperfonctions (modulo analyticité) et front d’onde analytique. Nous obtenons ainsi des théorèmes de prolongement ou d’unicité sur les ouverts linéellement concave. Nous obtenons aussi un théorème des résidus pour les valeurs au bord de classes de cohomologie définies sur les cônes de signatures (1, n − 1), clarifiant substantiellement des travaux de Cordaro-Gindikin-Trèves<br>The subject of this thesis is a microlocal approach to the transformation of Radon. It is a question of applying to real and complex projective duality the techniques initiated in the founding article of Sato-Kashiwara-Kawai of 1972 and to find, reformulate, improve more classic analytical work on this subject, in particular those of G. Henkin or S. Gindikin. Pro-jective duality seen from the microlocal and sheaf point of view appeared for the first time in an important work by J-L. Brylinski on perverse sheaves, work then taken up by D'Agnolo and Schapira in the framework of D-modules. Our work is to systematically resume this study with the new tools of the microlocal sheaf theory (theory which did not exist at the time of SKK72). This work essentially consists of two parts. In the first, we begin by recalling in a general framework the construction of quantized ca-nonical transformations, under the hypothesis of the existence of a simple non-degenerate section (introduced under another name by J. Leray). This construction had never been done in a global framework outside the projective case. We then show that these transfor-mations exchange the action of the microdifferential operators. This is a fundamental re-sult without any consistent proof existing in the literature, this result being more or less implied in SKK72. The second part of the thesis deals with the applications to the “classical” Radon trans-form. The basic idea is that this transform exchanges the support of hyperfunctions (modu-lo analyticity) and the analytic wavefront set. We thus obtain theorems of continuation or uniqueness on linearly concave domain. We also get a residue theorem for the boundary values of finite cohomology classes defined on cones with (1, n-1) signature, substantially clari-fying the work of Cordaro-Gindikin-Trèves
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Andrews, Robert Charles. "Modules over group algebras which are free on restriction to a maximal subgroup." Thesis, University of Warwick, 1987. http://wrap.warwick.ac.uk/98268/.
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Consider the following situation: k will be an algebraically closed field of characteristic p and G will be a finite p-group, V will be a non-projective, indecomposable kG-module which is free on restriction to some maximal subgroup of G. Our purpose in doing this is to investigate Chouinard's theorem - all the proofs of which have been cohomological in nature - in a representation-theoretic way. This theorem may be shown to be equivalent to saying that, if G is not elementary abelian, V cannot be free on restriction to all the maximal subgroups of G. It is shown how to construct an exact sequence: O → V → P → P → V → O with P projective. From this an almost split sequence, O → V → X → V → O is constructed. It is shown that X can have at most two indecomposable summands. If φ denotes the Frattini subgroup of G, then V is free on restriction to φ. We may regard the set of φ-fixed points of V, V̄, as a module for Ḡ =G/φ. But Ḡ is elementary abelian, so we may consider the Carlson variety, Y(V̄) - this may be regarded as a subset of J/J² where J denotes the augmentation ideal of kG. It is shown that Y(V̄) is always a line. We define YG to be the union of all the lines Y(V̄) as V runs over all the kG-modules with the properties above. It is shown that YG is the whole of J/J² if and only if G is elementary abelian. It is also shown that, when G is one of a particular class of p-groups - the pseudo-special groups - which form the minimal counter-examples to Chouinard's theorem, that YG is the set of zeros of a sequence of homogeneous polynomials with coefficients in the field of p elements. Indeed, a specific construction for these polynomials is given.
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Alessandrini, Daniele. "A tropical compactification for character spaces of convex projective structures." Doctoral thesis, Scuola Normale Superiore, 2007. http://hdl.handle.net/11384/85709.
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Gokhale, Dhananjay R. "Resolutions mod I, Golod pairs." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/39431.
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Let <i>R</i> be a commutative ring, <i>I</i> be an ideal in <i>R</i> and let <i>M</i> be a <i>R/ I</i> -module. In this thesis we construct a <i>R/ I</i> -projective resolution of <i>M</i> using given <i>R</i>-projective resolutions of <i>M</i> and <i>I</i>. As immediate consequences of our construction we give descriptions of the canonical maps Ext<sub>R/I</sub><i>(M,N)</i> -> Ext<sub>R</sub><i>(M,N)</i> and Tor<sup>R</sup><sub>N</sub><i>(M, N)</i> -> Tor<sup>R/I</sup><sub>n</sub><i>(M, N)</i> for a <i>R/I</i> module <i>N</i> and we give a new proof of a theorem of Gulliksen [6] which states that if <i>I</i> is generated by a regular sequence of length r then ∐∞<sub>n=o</sub> Tor<sup>R/I</sup><sub>n</sub> <i>(M, N)</i> is a graded module over the polynomial ring </i>R/ I</i> [X₁. .. X<sub>r</sub>] with deg X<sub>i</sub> = -2, 1 ≤ i ≤ r. If <i>I</i> is generated by a regular element and if the <i>R</i>-projective dimension of <i>M</i> is finite, we show that <i>M</i> has a <i>R/ I</i>-projective resolution which is eventually periodic of period two.
This generalizes a result of Eisenbud [3]. In the case when <i>R</i> = (<i>R</i>, m) is a Noetherian local ring and <i>M</i> is a finitely generated <i>R/ I</i> -module, we discuss the minimality of the constructed resolution. If it is minimal we call (<i>M, I</i>) a Golod pair over <i>R</i>. We give a direct proof of a theorem of Levin [10] which states thdt if (<i>M,I</i>) is a Golod pair over <i>R</i> then (Ω<sup>n</sup><sub>R/I</sub>R/I(M),I) is a Golod pair over <i>R</i> where Ω<sup>n</sup><sub>R/I</sub>R/I(M) is the nth syzygy of the constructed <i>R/ I</i> -projective resolution of <i>M</i>. We show that the converse of the last theorem is not true and if (Ω¹<sub>R/I</sub>R/I(M),I) is a Golod pair over <i>R</i> then we give a necessary and sufficient condition for (<i>M, I</i>) to be a Golod pair over <i>R</i>.
Finally we prove that if (<i>M, I</i>) is a Golod pair over <i>R</i> and if a ∈ <i>I</i> - m<i>I</i> is a regular element in </i>R</i> then (<i>M</i>, (a)) and (1/(a), (a)) are Golod pairs over <i>R</i> and (<i>M,I</i>/(a)) is a Golod pair over <i>R</i>/(a). As a corrolary of this result we show that if the natural map π : <i>R</i> → <i>R/1</i> is a Golod homomorphism ( this means (<i>R</i>/m, <i>I</i>) is a Golod pair over <i>R</i> ,Levin [8]), then the natural maps π₁ : <i>R</i> → <i>R</i>/(a) and π₂ : <i>R</i>/(a) → <i>R/1</i> are Golod homomorphisms.<br>Ph. D.
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Mehdi, Akeel Ramadan. "Purity relative to classes of finitely presented modules." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/purity-relative-to-classes-of-finitely-presented-modules(6ebd54f0-7b74-4f13-abb9-3f3594f93f6a).html.
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Any set of finitely presented left modules defines a relative purity for left modules and also apurity for right modules. Purities defined by various classes are compared and investigated,especially in the contexts of modules over semiperfect rings and over tame hereditary, andmore general, finite-dimensional algebras. Connections between the indecomposable relativelypure-injective modules and closure in the full support topology (a refinement of theZiegler spectrum) are described.Duality between left and right modules is used to define the concept of a class of leftmodules and a class of right modules forming an almost dual pair. Definability of suchclasses is investigated, especially in the case that one class is the closure of a set of finitelypresented modules under direct limits. Elementary duality plays an important role here.Given a set of finitely presented modules, the corresponding proper class of relativelypure-exact sequences can be used to define a relative notion of cotorsion pair, which weinvestigate.The results of this thesis unify and extend a wide range of results in the literature.
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Salazar, Pedroza Héctor Gabriel [Verfasser], Rüdiger [Akademischer Betreuer] Göbel та Ulrich [Akademischer Betreuer] Albrecht. "Combinatorial Principles and ﬡ_k-free Modules / Héctor Gabriel Salazar Pedroza. Gutachter: Ulrich Albrecht. Betreuer: Rüdiger Göbel". Duisburg, 2012. http://d-nb.info/1029288410/34.
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Hubbard, David. "The nonexistence of certain free pro-p extensions and capitulation in a family of dihedral extensions of Q /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/5734.
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Flon, Stéphane. "Mauvaises places ramifiées dans le corps des modules d'un revêtement." Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2002. http://tel.archives-ouvertes.fr/tel-00002259.
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Ce travail se fonde sur le lien entre le corps des modules d'un revêtement et les espaces de Hurwitz. Pour un revêtement donné, l'arithmétique de ces espaces fournit des résultats sur la ramification du corps des modules au-dessus du corps de rationalité des points de branchement. Le théorème de Beckmann, qui circonscrit la ramification dans cette extension à certaines places, les mauvaises places, trouve ainsi une démonstration naturelle. Une analyse plus fine des espaces de Hurwitz fournit des informations sur les mauvaises places ne divisant pas l'ordre du groupe de monodromie du revetement (mais où les points de branchement se rencontrent) : l'idée consiste à considérer le revêtement du complété de l'espace de Hurwitz au-dessus du complété de l'espace de configuration de points. Pour une telle place, le lieu de branchement du revêtement se prolonge en une section arithmétique sur ce dernier espace, et la restriction du revêtement de Hurwitz à cette section fournit de l'information sur la ramification dans le corps des modules en la place considérée. Nous étudions ce problème de restriction dans un cadre plus général, en considérant le cas d'un revêtement modérément ramifié le long de diviseurs à croisements normaux restreint à une section, et en nous basant sur le théorème d'Abhyankar. Nous donnons une version effective de ce résultat de ramification dans le corps des modules, en fonction d'entiers qui dépendent des relations de congruence entre les points de branchement, ainsi que d'un choix de générateurs de l'inertie autour des composantes du bord de l'espace de configuration de points croisant la section. À cet effet, nous introduisons un certain type de twists de Dehn, les twists sarments, et nous décrivons leur action sur l'ensemble des classes de Nielsen. Une dernière partie de ce travail regroupe des résultats divers de descente du corps de définition d'un revêtement, qui utilisent des gerbes au-dessus des espaces de Hurwitz.
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Siviero, Andrea. "Class invariants for tame Galois algebras." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00847787.
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Let K be a number field with ring of integers O_K and let G be a finite group.By a result of E. Noether, the ring of integers of a tame Galois extension of K with Galois group G is a locally free O_K[G]-module of rank 1.Thus, to any tame Galois extension L/K with Galois group G we can associate a class [O_L] in the locally free class group Cl(O_K[G]). The set of all classes in Cl(O_K[G]) which can be obtained in this way is called the set of realizable classes and is denoted by R(O_K[G]).In this dissertation we study different problems related to R(O_K[G]).The first part focuses on the following question: is R(O_K[G]) a subgroup of Cl(O_K[G])? When the group G is abelian, L. McCulloh proved that R(O_K[G]) coincides with the so-called Stickelberger subgroup St(O_K[G]) of Cl(O_K[G]). In Chapter 2, we give a detailed presentation of unpublished work by L. McCulloh that extends the definition of St(O_K[G]) to the non-abelian case and shows that R(O_K[G]) is contained in St(O_K[G]) (the opposite inclusion is still not known in the non-abelian case).Then, just using its definition and Stickelberger's classical theorem, we prove in Chapter 3 that St(O_K[G]) is trivial if K=Q and G is either cyclic of order p or dihedral of order 2p, where p is an odd prime number. This, together with McCulloh's results, allows us to have a new proof of the triviality of R(O_K[G]) in the cases just considered.The main original results are contained in the second part of this thesis. In Chapter 4, we prove that St(O_K[G]) has good functorial behavior under restriction of the base field. This has the interesting consequence that, if N/L is a tame Galois extension with Galois group G, and St(O_K[G]) is known to be trivial for some subfield K of L, then O_N is stably free as an O_K[G]-module.In the last chapter, we prove an equidistribution result for Galois module classes amongst tame Galois extensions of K with Galois group G in which a given prime p of K is totally split.
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Sáez, Araoz Rodrigo [Verfasser]. "Chemical bath deposition of Zn(S,O) buffer layers and application in Cd-free chalcopyrite-based thin-film solar cells and modules / Rodrigo Sáez Araoz." Berlin : Freie Universität Berlin, 2009. http://d-nb.info/1023816695/34.
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Nguyen, Tien Anh. "Instrumentation électronique et diagnostic de modules de puissance à semi-conducteur." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2013. http://tel.archives-ouvertes.fr/tel-00910357.
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Les objectifs de la thèse sont d'élaborer des systèmes d'instrumentation électronique qui permettent une analyse et un diagnostic fins de l'état d'intégrité et du processus de vieillissement des composants de puissance à semi-conducteur. Ces travaux visent à évaluer la variation de la conductivité de la métallisation à l'aide de capteurs à Courant Foucault (CF) mais aussi à estimer l'effet du vieillissement des puces et de leur assemblage sur la distribution de courant dans les puces afin de mieux comprendre les mécanismes de défaillance. Des éprouvettes simplifiées mais également des modules de puissance représentatifs ont été vieillis par les cyclages thermique. Les capteurs développés ont été utilisés afin, d'une part de suivre le vieillissement, mais aussi d'autre part afin de comprendre l'effet de ce vieillissement sur le comportement des puces de puissance. Un banc d'instrumentation dédié a été élaboré et exploité pour la mesure locale de la conductivité électrique par le capteur à courants de Foucault, et l'estimation de la distribution de courants à partir de la mesure de cartographies de champ magnétique par capteurs de champ, ou à partir de la cartographie de la distribution de tension sur la métallisation de source. Ce banc a permis en premier lieu d'évaluer la pertinence et les performances de différents types de capteurs exploitables. Le travail s'est également appuyé sur des techniques de traitement de signal, à la fois pour estimer de manière quantitative les informations de conductivité des métallisations issues des capteurs à courant de Foucault, mais aussi pour l'analyse de la distribution de courant à partir des informations fournies par des capteurs de champ magnétiques. Les modèles utilisés exploitent des techniques de modélisation comportementale (le modèle approché de " transformateur analogique " modélisant capteurs à CF ou bien d'inversion de modèle semi-analytique dans le cas l'estimation de la distribution de courant). Les résultats obtenus à partir de ces modèles nous permettrons, d'une part de mieux comprendre certains mécanismes de défaillance, mais également de proposer une implantation et des structures de capteurs pour le suivi " in situ " de l'intégrité des composants.
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Mamani, Santiago Miler Quispe. "Decomposição de módulos livres de torção como soma direta de módulos de posto 1." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/3244.
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Previous issue date: 2016-04-25<br>O objetivo deste trabalho é apresentar o resultado dado por Bass em [4], que determina uma condição no domínio de integridade R para que todo módulo finitamente gerado e livre de torção seja escrito como soma direta de módulos de posto 1. Mostramos que uma condição necessária é que todo ideal em R seja gerado por dois elementos, ou seja, que esses domínios sejam quase domínios de Dedekind. Em seguida, aplicamos o resultado na descrição de módulos livres de torção e de posto finito sobre os anéis de coordenadas de curvas singulares, cujas singularidades são nós ou cúspides.<br>The aim of this paper is to present the result given by Bass in [4], which determines a condition on the integral domain R so that every finitely generated torsion free module is written as a direct sum of modules of rank 1. We show that a necessary condition is that all ideal in R is generated by two elements, in other words, that these domains are almost Dedekind domains. Then, we apply the result in the description of torsion free modules of finite rank over the coordinate rings of singular curves, whose singularities are nodal or cuspidal.
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Halic, Mihai. "Symplectique vs projectif." Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10011.
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L'idee directrice de cette these est de regarder les varietes symplectiques compactes comme des mauvaises varietes projectives. La these est divisee en quatre parties. La premiere partie rappelle certaines definitions et resultats de la geometrie symplectique. Dans la deuxieme partie, nous etudions la geographie des varietes symplectiques compactes, connexes et simplement connexes de dimension reelle six. Pour chaque triplet (2a, 24b, 2c), avec a, b, c des entiers, nous construisons des exemples de telles varietes dont le triplet de chern (c#3#1, c#1, c#2, c#3) est precisement le triplet donne. Dans la troisieme partie, nous etudions la possibilite d'etendre au cas symplectique la technique de bend-and-break en geometrie algebrique. La quatrieme partie est consacree a l'etude des liens entre les invariants de gromov-witten d'une variete projective et ceux de son quotient invariant sous l'action d'un groupe algebrique reductif. A cause des difficultes techniques, nous demontrons ces relations seulement dans le cas des varietes drapeaux.
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Ugolini, Matteo. "K3 surfaces." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/18774/.
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Alves, Marcela Guerrini. "Realização de campos livres de álgebras de Kac-Moody afim." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/45/45131/tde-29092017-114301/.
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Este trabalho tem como objetivo principal estudar módulos irredutíveis sobre as álgebras de Kac-Moody afim, conforme [7]. Em particular, a técnica de localização foi aplicada aos módulos de Verma imaginários sobre a álgebra de Lie afim A(1)1, com o objetivo de obter novos módulos irredutíveis sobre essa álgebra. Conforme [8] e [6], é o mesmo que aplicar a técnica de localização à primeira realização de campos livres de A(1)1 .Para cumprir o objetivo, introduzimos as álgebras de Kac-Moody, tendo como foco principal as álgebras de Kac-Moody do tipo afim, conforme [14]. Em seguida, definimos os módulos de Verma,destacando os módulos de Verma imaginários sobre a álgebra de Lie afim A(1)1, conforme [8].<br>The main purpose of this work is to study the irreducible modules of affine Kac-Moody algebras,according to [7].In particular, the localization technique was applied to the imaginary Verma modules of affine Lie algebra A(1)1, with the purpose to obtain new irreducible modules of this algebra. According to[8] and [6], it is the same as to apply the localization technique to the first realization of free fields of A(1)1.To achieve the purpose, we introduced the Kac-Moody algebras, having the main focus the af-fine Kac-Moody algebras, according to [14]. Following, we defined the Verma modules, highlighting imaginary Verma modules of affine Lie algebra A(1)1, according to [8].
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Koz, Alper. "Watermarking For 3d Representations." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608886/index.pdf.
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In this thesis, a number of novel watermarking techniques for different 3D representations are presented. A novel watermarking method is proposed for the mono-view video, which might be interpreted as the basic implicit representation of 3D scenes. The proposed method solves the common flickering problem in the existing video watermarking schemes by means of adjusting the watermark strength with respect to temporal contrast thresholds of human visual system (HVS), which define the maximum invisible distortions in the temporal direction. The experimental results indicate that the proposed method gives better results in both objective and subjective measures, compared to some recognized methods in the literature.
The watermarking techniques for the geometry and image based representations of 3D scenes, denoted as 3D watermarking, are examined and classified into three groups, as 3D-3D, 3D-2D and 2D-2D watermarking, in which the pair of symbols identifies whether the watermark is embedded-detected in a 3D model or a 2D projection of it. A detailed literature survey on 3D-3D watermarking is presented that mainly focuses on protection of the intellectual property rights of the 3D geometrical representations. This analysis points out the specific problems in 3D-3D geometry watermarking , such as the lack of a unique 3D scene representation, standardization for the coding schemes and benchmarking tools on 3D geometry watermarking.
For 2D-2D watermarking category, the copyright problem for the emerging free-view televisions (FTV) is introduced. The proposed watermarking method for this original problem embeds watermarks into each view of the multi-view video by utilizing the spatial sensitivity of HVS. The hidden signal in a selected virtual view is detected by computing the normalized correlation between the selected view and a generated pattern, namely rendered watermark, which is obtained by applying the same rendering operations which has occurred on the selected view to the original watermark. An algorithm for the estimation of the virtual camera position and rotation is also developed based on the projective planar relations between image planes. The simulation results show the applicability of the method to the FTV systems.
Finally, the thesis also presents a novel 3D-2D watermarking method, in which a watermark is embedded into 3-D representation of the object and detected from a 2-D projection (image) of the same model. A novel solution based on projective invariants is proposed which modifies the cross ratio of the five coplanar points on the 3D model according to the watermark bit and extracts the embedded bit from the 2D projections of the model by computing the cross-ratio. After presenting the applicability of the algorithm via simulations, the future directions for this novel problem for 3D watermarking are addressed.
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Soomro, Munawar Hussain. "Health effects of endocrine disruptors during pregnancy and childhood Exposure to heavy metals during pregnancy related to gestational diabetes mellitus in diabetes-free mothers Prenatal exposure to phthalates and the development of eczema phenotypes in male children: Results from the EDEN mother-child Cohort study." Thesis, Sorbonne université, 2019. https://accesdistant.sorbonne-universite.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2019SORUS243.pdf.
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Les perturbateurs endocriniens (PE) sont des composés synthétiques capables de se lier aux récepteurs cellulaires et d'imiter ou de bloquer le fonctionnement des hormones naturelles, pouvant ainsi entraîner des effets néfastes sur la santé. Ces dernières années, des hypothèses ont été émises selon lesquelles les PE pourraient également contribuer au développement de maladies allergiques et respiratoires. En outre, il est probable que les PE pourraient déjà agir pendant la grossesse en provoquant un diabète gestationnel (DG) et une hypertension induite par la grossesse, pouvant également provoquer une hypertension et un diabète plus tard dans la vie. Ce travail de thèse a permis de mettre en évidence que l'exposition maternelle aux phtalates et aux métaux lourds (plomb, cadmium et manganèse) pendant la grossesse pourrait être associée au diabète gestationnel, à l'hypertension induite par la grossesse et à l'eczéma/dermatite atopique chez l'enfant. Nous avons utilisé les données de la cohorte Française de naissance mère-enfant, EDEN (Étude des déterminants pré et post-natals du développement de la santé de l’enfant) pour examiner les hypothèses de ce travail de thèse. Nos résultats apportent de nouvelles preuves potentielles sur la relation entre les perturbateurs endocriniens (phtalates et métaux lourds étudiés) et la santé de la mère et de l’enfant, selon lesquelles l’exposition prénatale à certains phtalates et métaux toxiques lourds pourrait jouer un rôle dans le développement du diabète gestationnel et de l’hypertension induite par la grossesse pendant la grossesse et, ultérieurement, un eczéma pendant la petite enfance<br>All humans are exposed to chemicals in everyday life, from food, indoor environment, cosmetics and other products that surround us at home and at work. Endocrine disruptors (EDCs) are man-made compounds that can bind to cell receptors and mimic or block the functions of natural hormones potentially resulting in adverse health effects. In recent years, hypotheses have been put forward that EDCs may contribute also to the development of allergic and respiratory diseases. In addition, it is likely that EDCs could act already during pregnancy by causing gestational diabetes mellitus and pregnancy induced hypertension, which may also trigger to develop hypertension and diabetes mellitus later in life. This dissertation provides evidence that maternal exposure to phthalates and heavy metals (Lead, Cadmium and Manganese) during pregnancy may be associated with gestational diabetes mellitus, pregnancy induced hypertension and later eczema/atopic dermatitis in children. We used ongoing French EDEN-mother child cohort data for our three studies. Our results add new suggestive evidence on the relationship between EDCs (phthalates and heavy metals we studied) and maternal and children health, that prenatal exposure to certain phthalates and heavy toxic metals may play a role in the development of gestational diabetes mellitus and pregnancy induced hypertension during pregnancy and later eczema in early childhood. Future research focusing on larger populations and addressing multiple exposures assessed prenatally and postnatally are required to provide more evidence on possible contributions of emerging pollutants to study the role of phthalates and heavy metals
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Pavarin, Alice. "Equivalences of additive categories." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3422598.
Full textAbstract:
In the first part of the thesis, after an introduction of the concept of recollement
and TTF triple in a triangulated category, we consider recollements of derived categories
of differential graded algebras induced by self-orthogonal compact objects
obtaining a generalization of Rickard's Theorem. Specializing to the case of partial
tilting modules over a ring, we extend the results on triangle equivalences proved
in [B] and [BMT]. After that we focus on the connection between recollements
of derived categories of rings, bireflective subcategories and generalized universal
localizations". In the second part of the thesis we give some results in the setting
of monoidal categories and dual qausi-bialgebras. To every dual quasi-bialgebra H
and every bialgebra R in the category of Yetter-Drinfeld modules over H, one can
associate a dual quasi-bialgebra, called bosonization. In this thesis, using the fundamental
theorem, we characterize as bosonizations the dual quasi-bialgebras with
a projection onto a dual quasi-bialgebra with a preantipode. As an application we
investigate the structure of the graded coalgebra grA associated to a dual quasibialgebra
A with the dual Chevalley property (e.g. A is pointed).<br>Nella prima parte della tesi, dopo aver introdotto il concetto di incollamento e
di triple TTF in una categoria triangolata, si considerano incollamenti di categorie
derivate di algebre differenziali graduate indotti da oggetti compatti e auto ortogonali,
ottenendo una generalizzazione del teorema di Rickard. Considerando
il caso particolare del moduli partial tilting, estendiamo i risultati sulle equivalenze
tra categorie triangolate ottenute in [B] e [BMT]. Segue una parte focalizzata
sulla connessione tra incollamenti di categorie derivate di anelli, sottocategorie biriflessive e localizzazioni universali generalizzate. Nella seconda parte della tesi vengono
dati alcuni risultati nell'ambito di categorie monoidali e dual quasi-bialgebre.
Ad ogni dual quasi-bialgebra H e ad ogni bialgebra R nella categoria dei moduli
di Yetter-Drinfeld su H, e possibile associare una dual quasi-bialgebra, chiamata
bosonizzazione. In questa tesi, usando il teorema fondamentale, si caratterizza come
bosonizzazione ogni dual quasi-bialgebra con proiezione su una dual quasi-bialgebra
con preantipode. Come applicazione si studia la struttura della coalgebra graduata
grA associata ad una dual quasi-bialgebra A con la proprieta di Chevalley duale (si
vedra che A e puntata).
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Lenoir-Capello, Rachel. "Specific labeling strategies for new developments in liquid state protein NMR." Thesis, Sorbonne université, 2020. https://accesdistant.sorbonne-universite.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2020SORUS056.pdf.
Full textAbstract:
La résonance magnétique nucléaire (RMN) fournit des informations structurelles et dynamiques précieuses à l'échelle atomique, cependant, la faible sensibilité et résolution des signaux empêchent l’étude d'objets moléculaires plus importants. Nous présentons 3 stratégies de marquage isotopique pour différentes expériences RMN des protéines en solution et démontrons leur potentiel pour l'étude structurale des biomolécules. Parmi les stratégies envisagées, 2 utilisent l'expression in vitro pour obtenir des protéines marquées sélectivement sur un groupe chimique et/ou acide aminé dans un environnement perdeutéré. Avec l’utilisation de séquences d'impulsions TROSY, ces échantillons ont permis des gains spectraux importants lorsque ils étaient spécifiquement marqués sur des groupes amide ou sur le méthylène des glycines tout en maintenant un taux de deutération élevé sur les autres fonctions chimiques des protéines. La troisième stratégie de marquage protéique utilise des protocoles in vivo pour des applications RMN innovantes: l'hyperpolarisation de noyaux en solution qui augmente leur sensibilité de plusieurs ordres de grandeur. La durée de vie de cette hyperpolarisation est régie par le temps de relaxation longitudinale des noyaux, qui est réduit pour les protéines à température ambiante. En isolant les noyaux d'intérêt dans un environnement perdeutéré, les interactions dipolaires créées par les protons voisins sont éliminées et les noyaux hyperpolarisés relaxent beaucoup plus lentement. L'hyperpolarisation d'un petit domaine protéique a été entreprise avec succès mais les conditions de dissolution doivent encore être améliorées pour conserver une phase aqueuse homogène<br>Nuclear Magnetic Resonance (NMR) provides valuable structural and dynamic information at the atomic scale, however, the low sensitivity and resolution of signals rapidly preclude investigations of larger molecular objects. We present three isotopic labeling strategies for different protein-solution NMR experiments and demonstrate their potential for the structural study of biomolecules in solution. Among the strategies considered, two are based on the use of in vitro protein expression to obtain selectively labeled proteins of a certain chemical group and/or amino acid in a perdeuterated environment. Perdeuteration is essential for the optimal use of Transverse Relaxation Optimized Spectroscopy pulse sequences. They allowed significant spectral gains when samples were specifically labeled on amide groups or on the methylene of glycines while maintaining a very high rate of deuteration on the other chemical functions of the proteins. The third protein labeling strategy employed is based on in vivo protocols but used in innovative NMR applications: a technique of hyperpolarization of nuclei in solution which increases their sensitivity by several orders of magnitude. The lifetime of this hyperpolarization is governed by the longitudinal relaxation time of nuclei, which are reduced for proteins at room temperature. By isolating the nuclei of interest in a perdeuterated environment, dipolar interactions created by neighboring protons were eliminated and hyperpolarized nuclei relaxed much more slowly. Hyperpolarization of a small protein domain was successfully undertaken at 1K but the dissolution conditions need to be improved in order to preserve a homogeneous aqueous phase
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Arabi, Faical. "Étude de vieillissement et caractérisation d’assemblage de module de puissance 40 kW pour l’aéronautique." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0603/document.
Full textAbstract:
Ces travaux s’inscrivent dans le cadre du projet GENOME (GEstioN OptiMisée de l’Energie). Ce projet s’intéresse aux solutions de packaging haute-température pour des modules de puissance 40 kW embarqués en aéronautique. Ils s’intègrent dans l’étude de fiabilité des modules de puissance, notamment, les solutions alternatives aux alliages de brasure. De par leurs propriétés physiques, l’argent et l’or-étain ont été sélectionnés comme techniques d’assemblage afin d’étudier et d’évaluer leur fiabilité. Pour ce faire, une méthodologie d’étude de fiabilité des modules de puissance a été définie dans le but de garantir l’exploitabilité des résultats. Ensuite, des analyses destructives et non-destructives ont été réalisées sur des véhicules de tests. Ceux-ci ont été vieillis en cyclages thermiques suivant différents profils afin de comparer leurs influences sur la fiabilité des VTs. L’étude du comportement thermomécanique des assemblages de puissance a été réalisée à l’aide de modélisations par éléments finis. Une méthodologie d’évaluation de la fiabilité des assemblages, basée sur l’étude de la contrainte thermomécanique accumulée dans les couches de joints métalliques, au cours de vieillissements accélérés, est développée. Un deuxième axe devrait permettre de comprendre les modes de défaillance, afin de mettre en lumière les limitations des vieillissements accélérés sévères<br>This work is part of “GENOME” project which focuses on high-temperature packaging solutions for electronic power modules. Its mission is to study the reliability of power modules, in particular, the die attach layer. Due to the physical properties of silver and gold-tin, they were selected as die bonds to assess the evolution of their reliability during ageing. In order to achieve this, an appropriate methodology of the power modules reliability has been defined in order to guarantee the results exploitability. Destructive and non-destructive analyzes were carried out on samples aged by different profiles of thermal cycling. These analyzes allowed us to compare the influence of each cycling profile on the reliability of samples. A study of the thermomechanical behavior of power assemblies was carried out using finite element modeling (FEM). A methodology for evaluating the reliability of assemblies during accelerated ageing is developed. A second axis allows us a better understanding of the failure modes and their effects. It also highlights the limitations of severe accelerated ageing. Consequently, the choice of temperature profile is questioned and a limitation of the temperature profile severity must be considered, in order to avoid producing degradations that are not actually found in mission profile
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Khalil, Maya. "Classes de Steinitz, codes cycliques de Hamming et classes galoisiennes réalisables d'extensions non abéliennes de degré p³." Thesis, Valenciennes, 2016. http://www.theses.fr/2016VALE0012/document.
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Αρβανίτη, Παναγιώτα. "Επί των πεπερασμένα γενόμενων προβολικών modules επί του δακτυλίου k[x_1,...,x_m]". Thesis, 2014. http://hdl.handle.net/10889/8137.
Full textAbstract:
Η διπλωματική εργασία κινείται γύρω από το θεώρημα Quillen-Suslin (1976):
“Κάθε πεπερασμένα γενόμενο προβολικό module επί του δακτυλίου των πολυωνύμων k[x_1,…,x_m ] (όπου k σώμα) είναι ελεύθερο”.
Το πρόβλημα ξεκίνησε το 1955, όταν ο J. P. Serre, σε υποσημείωση της ένδοξης εργασίας του “Faisceaux Algebriques Coherents” (σελίδα 243), σημειώνει:
“ On ignore s’il existe des A-modules projectifs de type fini qui ne soient pas libres” (A=k[x_1,…x_m ], k σώμα).*
Το πρόβλημα λύθηκε από τους Quillen και Suslin (ανεξάρτητα) είκοσι χρόνια μετά. Για την απόδειξη του θεωρήματος είναι απαραίτητο το αποτέλεσμα που οφείλεται στον ίδιο τον Serre (1958):
“ Κάθε πεπερασμένα γενόμενο προβολικό k[x_1,…,x_m ]-module P είναι σταθερά ελεύθερο” (δηλαδή το P δέχεται πεπερασμένα γενόμενο ελεύθερο συμπλήρωμα F, ώστε το P⊕F να είναι ελεύθερο).
Στo Κεφάλαιο 2 αυτής της εργασίας, θα παρουσιάσουμε την απόδειξη του ανωτέρω θεωρήματος του Serre και τελικά, στο Κεφάλαιο 3, θα σκιαγραφήσουμε την απόδειξη του θεωρήματος Quillen-Suslin, με τη μέθοδο του Suslin. *Αγνοούμε αν υπάρχουν πεπερασμένα γενόμενα προβολικά A-modules που δεν είναι ελεύθερα.<br>This work is about the Quillen-Suslin Theorem (1976):
“If k is a field , then every finitely generated projective k[x_1,…,x_m ]-module is free”.
This problem started in 1955, when J.P. Serre, in his glorious paper “FaisceauxAlgebriquesCoherents” (page 243), noted:
“On ignore s’ilexiste des A-modules projectifs de type fini qui ne soient pas libres ” (A=k[x_1,…x_m ],k is field).*
This problem was solved from Quillen and Suslin (independently) twenty years after. For the proof of this theorem is necessary the result, due to Serre (1958):
“Every finitely generated projective k[x_1,…,x_m ]-module P is stably free ” (ie. P admits a finitely generated free complement F, so that P⊕F is free).
In Chapter 2 of this work, we will represent the proof of the above Serre’s Theorem and, finally, in Chapter 3, we will sketch the proof of Quillen-Suslin's Theorem, with Suslin’s method.
*We ignore, if exist finitely generated projective A-modules, that they are not free.
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Chen, Sun-Huei, and 陳善慧. "projective modules and Grothendieck groups." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/70288847409113678027.
Full textAbstract:
碩士<br>淡江大學<br>數學系<br>81<br>As we know, projective modules are close to being free, in view
of the following basic characterization : M is a projective iff
M is a direct summand of a free module. According to some
proposition of a projective module, it is easy to check that
any free module is a projective module. Conversely, it is not
true. Thus it is interesting to survey some situations in which
projective modules are free modules. In the first chapter, we
consider the definition,prop- erties, and examples of a
projective modules. In the second chapter, we consider some
special modules, for examples: flat modules, faithfully flat
modules and finit- ely presented modules. Then in the forth
chapter, we obtain the following result: M is a projective R-
module and finitely presented iff the localization of M at a
prime idael P of R is free in the local- ization of R at P. We
also define the rank of a projective R- module M at a prime
ideal P of R is the rank of the localizat- ion of M at P. In
the fifth chapter, we consider the Dedekind ring i.e. a domain
in which every non zero ideal is invertible. We also discuss
the relatiohship between Dedkind rings and projective modules
and we show that the followings are equivelent: (1) M is
invertible. (2) M is a projective module of rank 1. The goal of
the sixth chapter is to give an intrinsic characterzation of
rings R for which every R-submodule of an arbitrary projective
R-module is projective. Finally, we give a quick introduction
to the theory of the Grothendieck groups for arbitrary rings.
Here we discover that: under some special rings, the
Grothendieck group is isomorphic to Z(integer ring).
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"Quasi-projective modules over integral domains." Tulane University, 2000.
Find full textAbstract:
We study quasi-projective modules over integral domains. A module M is called quasi-projective if it has the projective property relative to all exact sequences of the form 0 → N → M → M/N → 0, where N is a submodule of M. Quasi-projective modules have been introduced by Miyashita as a generalization of projective modules The main goals of our research are to generalize the results on quasi-projective modules over valuation domains to arbitrary integral domains and to study special types of quasi-projective modules, e.g. uniserial modules The dissertation consists of two parts The first part is concerned with quasi-projective modules over general domains. The main results of the first part are the following. (1) The so-called 1½-generated ideals are quasi-projective, moreover, projective. (2) The quotient field Q of an integral domain R is a quasi-projective R-module if and only if every proper submodule of Q is complete in its R -topology. (3) Integral domains all of whose ideals are quasi-projective are exactly the almost maximal Prufer domains The second part of the dissertation is primarily devoted to quasi-projective uniserial modules over valuation domains. The main results of the second part are the following. (1) Uniserial module U is quasi-projective if and only if it is weakly quasi-projective and an additional technical requirement is satisfied. (2) For torsion free modules of rank 1, quasi-projectivity is equivalent to the weak quasi-projectivity, and the latter is determined by completeness of certain endomorphism rings in their ring topologies. (3) The archimedean ideals of a valuation domain R with non-principal maximal ideal P are quasi-projective if and only if R/K is complete in the R/ K-topology for each archimedean ideal K, not isomorphic to P In conclusion we investigate the influence of quasi-projectivity on the decomposability of modules over valuation domains as well as on the properties of direct sums of such modules. We show that a torsion-free quasi-projective module M over a valuation domain which has a dense basic submodule is completely decomposable and that direct sums of ℵ -generated uniserial modules of cardinality less than ℵ are quasi-projective<br>acase@tulane.edu
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Maltenfort, Michael. "Addition and subtraction of ideals /." 1997. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:9729845.
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Robertson, Ian. "The Euler class group of a line bundle on an affine algebraic variety over a real closed field /." 2000. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:9965149.
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Hsu, Ya-Wen, and 徐雅文. "A Study of Interrelationship On Free Application Product Life Cycle And Schmitt Modules." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/45347225418674446157.
Full textAbstract:
碩士<br>淡江大學<br>大眾傳播學系碩士班<br>102<br>APP Product Life Cycle, the subject discussed by this study, refers to the course of APP commercialization (downloaded to users’ mobile phones) for people’s use. This study attempted to construct APP product usage dimensions based on the five experiential dimensions contained in Strategic Experiential Modules (SEMs) and to verify if the five experiential dimensions were capable of predicting APP Product Life Cycle, and thus analyzed the relationship between experiences and APP Product Life Cycle. Finally, this study acquired five curves representing different APP Product Life Cycles.
1. APP for communication: featured bythe highest frequency of use. APP Product Life Cycle appears steady after its growth period, and has a “stable and matured” curve. With the influence imposed by the related experiences, the curve rises steadily.
2. APP for community: noted for thesecond highest frequency of use. People use APP for community in the same way as people use APP for communication. APP Product Life Cycle has a “stable and matured” curve. With the influence imposed by the related experiences, the curve rises steadily.
3. APP for real-time information: featured byhigh frequency of use and short service time. Generally, users may acquire real-time information without activating APP. APP Product Life Cycle appears steady after its growth period, and has a “stable and matured” curve, which is lower than the curve of APP for communication and the curve of APP for community. Similarly, with the influence imposed by the related experiences, the curve rises steadily.
4. APP for navigation: people use it only when they have to. APP Product Life Cycle rises and falls, depending on whether people use it. APP Product Life Cycle has a “circulated half and circulated again” curve. The curve’s fluctuation range is influenced by the sensory experience and by the related experience.
5. APP for games: users’ behaviors are distributed extremely. Some people use it frequently; thus, APP Product Life Cycle has a “stable and matured” curve. Others rarely use it and do not activate it everyday. When they activate it, they use it for a short time. The curve rises and falls, depending on whether people use it or not. Thus, APP Product Life Cycle has a “circulated half and circulated again” curve.
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"Morita equivalence and isomorphisms between general linear groups." Chinese University of Hong Kong, 1994. http://library.cuhk.edu.hk/record=b5888249.
Full textAbstract:
by Lok Tsan-ming.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 1994.<br>Includes bibliographical references (leaves 74-75).<br>Introduction --- p.2<br>Chapter 1 --- "Rings, Modules and Categories" --- p.4<br>Chapter 1.1 --- "Rings, Subrings and Ideals" --- p.5<br>Chapter 1.2 --- Modules and Categories --- p.8<br>Chapter 1.3 --- Module Theory --- p.13<br>Chapter 2 --- Isomorphisms between Endomorphism rings of Quasiprogener- ators --- p.24<br>Chapter 2.1 --- Preliminaries --- p.24<br>Chapter 2.2 --- The Fundamental Theorem --- p.31<br>Chapter 2.3 --- Isomorphisms Induced by Semilinear Maps --- p.41<br>Chapter 2.4 --- Isomorphisms of General linear groups --- p.46<br>Chapter 3 --- Endomorphism ring of projective module --- p.54<br>Chapter 3.1 --- Preliminaries --- p.54<br>Chapter 3.2 --- Main Theorem --- p.60<br>Bibliography --- p.74
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Yudin, Ivan. "On projective resolutions of simple modules over the Borel subalgebra S^+(n, r) of the Schur algebra S(n, r) for n ≤3." Doctoral thesis, 2007. http://hdl.handle.net/11858/00-1735-0000-000D-F12B-3.
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Tsai, Chien-Cheng, and 蔡見政. "A Study on Satisfaction of Constructing Web-Based Classroom Management by Using School Free Software Modules." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/19269130830940065524.
Full textAbstract:
碩士<br>雲林科技大學<br>資訊管理系碩士班<br>97<br>One of the recent major issues in education revolution in Taiwan concerns integration of IT in the learning environment of schools. This study discussed the use of SFS in constructing a digitized classroom management model, it allowed integration of Internet and SFS platform, to facilitate classroom management by teachers. The system provided a triangular interaction between teachers, students and parents, which facilitate the participation in classroom activities and progression in learning, and further enhances a better learning environment.
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Wen-MingChen and 陳文明. "Study of Molten Lead-free Solder Deposited by Inkjet Printing for Bonding of Thin-film Solar Cell Modules." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/45848479773543162118.
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碩士<br>國立成功大學<br>材料科學及工程學系碩博士班<br>101<br>The photovoltaic industry is fast growing and the fabrication of solar cells has been kept improving. Nowadays, the main type of solar cell development is thin-film solar cells. However, most of studies focus on the solar cell structure to enhance the photovoltaic conversion efficiency rather than improving the solar module packaging process.
For module packaging process, the bus wire bonding and the encapsulation of solar cells are needed in the fabrication of thin-film solar cell. In order to keep stable photovoltaic conversion efficiency after module packaging, good bonding strength is required between copper ribbon and aluminum back electrode of thin-film solar cell. Inkjet printing technology is a non-contact direct fabrication process, which can control precise droplet size and position and reduce material consumption. This study used lead-free solder as bonding material by inkjet printing process and module packaging technology for getting better quality of solar cell modules.
In this study, Sn3.0Ag0.5Cu solders were successfully printed by using inkjet printing technology for bonding of thin-film solar cell modules. The results show that the peel strength of lead-free solder is better than that of silver paste when the dot spacing of lead-free droplets is lower than 200 μm. In other words, the amount of lead-free solder is over than 50 μg/mm2. As the bonding strength increases, the efficiency loss decreases. The optimum results of low efficiency loss degrade 1.5 % and good photovoltaic conversion efficiency is over 8.3 %.