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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Unique determination of quadratic differentials by their admissible functions

Kim, Hye Seon 28 September 2011 (has links)
Let f be an analytic and one-to-one function on the unit disk such that f(0)=0. Let Q(w)dw^2 be a quadratic differential. Suppose that f maps into the complex plane or the unit disk minus analytic arcs w(t) satisfying Q(w(t))(dw/dt)^2<0. We are interested in the question: if Q is unknown but of a specified form, does f determine the quadratic differential Q uniquely? Our main result is that for functions mapping into the unit disk and quadratic differentials with a pole of order 4 at the origin, the quadratic differential is uniquely determined up to exceptional cases. This question arises in the study of extremal functions for functionals over classes of analytic one-to-one maps.
2

Unique determination of quadratic differentials by their admissible functions

Kim, Hye Seon 28 September 2011 (has links)
Let f be an analytic and one-to-one function on the unit disk such that f(0)=0. Let Q(w)dw^2 be a quadratic differential. Suppose that f maps into the complex plane or the unit disk minus analytic arcs w(t) satisfying Q(w(t))(dw/dt)^2<0. We are interested in the question: if Q is unknown but of a specified form, does f determine the quadratic differential Q uniquely? Our main result is that for functions mapping into the unit disk and quadratic differentials with a pole of order 4 at the origin, the quadratic differential is uniquely determined up to exceptional cases. This question arises in the study of extremal functions for functionals over classes of analytic one-to-one maps.
3

Paires admissibles d'une algèbre de Lie simple complexe et W-algèbres finies / Admissible pairs of a complex simple Lie algebra and finite W-algebras

Sadaka, Guilnard 06 December 2013 (has links)
Soient g une algèbre de Lie simple complexe et e un élément nilpotent de g. Nous nous intéressons dans ce mémoire à la question (soulevée par Premet) d'isomorphisme entre les W-algèbres finies construites à partir de certaines sous-algèbres nilpotentes de g dites e-admissibles. Nous introduisons les notions de paire et graduation e-admissibles. Nous montrons ensuite que la W-algèbre associée à une paire e-admissible possède des propriétés similaires à celle introduite par Gan et Ginzburg. De plus, nous définissons une relation d'équivalence sur l'ensemble des paires admissibles. Nous montrons alors que si deux paires sont équivalentes, alors les W-algèbres associées sont isomorphes. Nous introduisons enfin les notions de graduation et paire admissibles b-maximales et nous montrons que les paires admissibles b-maximales sont équivalentes entre elles. Comme conséquence de ce résultat, nous retrouvons un résultat de Brundan et Goodwin sur les bonnes graduations. Dans une dernière partie, nous considérons des cas particuliers pour lesquels nous pouvons apporter une réponse complète à la question d'isomorphisme. / Let g be a complex simple Lie algebra and e a nilpotent element of g. We are interested to answer the isomorphism question (raised by Premet) between the finite W-algebras constructed from some nilpotent subalgebras of g called e-admissible. We introduce the concept of e-admissible pair and e-admissible grading. We show then that the W-algebra associated to an e-admissible pair admits similar properties to that introduced by Gan and Ginzburg. Moreover, we define an equivalence relation on the set of admissible pairs and we show that if two admissible pairs are equivalent, it follows that the associated W-algebras are isomorphic. We introduce later the concepts of b-maximal admissible pair and b-maximal admissible grading and show that b-maximal admissible pairs are equivalent. As a consequence to this result, we recover a result of Brundan and Goodwin on the good gradings. In a final part, we consider some particular cases where we may find a complete answer to the isomorphism question.
4

Is unusual inadmissible evidence more difficult to ignore than neutral inadmissible evidence? / Unusual inadmissible evidence

Karam, Tanya J. January 2007 (has links)
This experiment was a replication and extension of Pickel, Karam, and Warner's (2006) study by using wiretap evidence instead of hearsay. The design was a 2 (admissibility) X 2 (unusualness) factorial with a control group that had no critical evidence. Participants were 129 mock jurors who listened to an audio-recording of a trial and made some decision about the case. Results showed that the critical evidence had no effect on guilt judgments. However, the unusualness manipulation did have an effect on the memory of the critical testimony, in that the participants in the unusual groups had a better memory than the neutral groups. Explanations of the results are discussed, along with limitations and suggestions for future research. / Department of Psychological Science
5

Classification of Irreducible Admissible mod-p Representations of GL_2(Q_p)

Menake Wijerathne, Wijerathne Mudiyanselage 01 December 2018 (has links)
In this thesis, we classify all irreducible admissible mod-p representations ofGL2(Qp)and divide those into 4 exhaustive disjoint categories. This classification was first pioneered by Barthel-Livne (1994-95), and completed by Breuil (2003). This thesis is mainly based on the lecture notes by Herzig (2015).
6

Interactions between quantifiers and admissible sets

Wimmers, Edward Leo. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. Includes bibliographical references (leaf 145).
7

Étude des restrictions des séries discrètes de certains groupes résolubles et algébriques / On the restrictions of discrete series of certain algebraic solvable Lie groups

Kouki, Sami 01 March 2014 (has links)
Soit G un groupe de Lie résoluble connexe et H un de ses sous-groupes fermés connexes d'algèbres de Lie g et h respectivement. On note g* (resp. h*) le dual linéaire de g (resp. h) ). Le sujet de ma thèse consiste à étudier la restriction d'une série discrète π de G, associée à une orbite coadjointe Ω C g*, à H. Si la restriction de π à H se décompose en somme directe de représentations de H avec multiplicités finies, on dit que π est H-admissible. Notons Pg,n : Ω → h* l'application restriction. Il s'agit de démontrer la conjecture suivante due à Michel Duflo : 1. La représentation π est H-admissible si et seulement si l'application moment Pg,n est propre sur l'image. 2. Si π est H-admissible, et si T est une série discrète de H alors sa multiplicité dans la restriction de π à H doit pouvoir se calculer en « quantifiant » l'espace réduit correspondant (qui est compact dans ce cas). Dans cette thèse, nous apportons une réponse positive à cette conjecture dans deux situations, à savoir :(i) Le groupe G est résoluble exponentiel. (ii) Le groupe G est le produit semi direct d'un tore compact par le groupe de Heisenberg et H est un sous-groupe algébrique connexe. / Let G be a connected solvable Lie group and H a closed connected subgroup with Lie algebra g and h respectively. We denote g* (resp. h*) the dual of g (resp. h). The aim of my thesis is to study the restriction of a discrete series π of G, associated with a coadjoint orbit Ω C g* to H. If the restriction of π to H can be decomposed in to a direct sum of representations of H with finite multiplicities, we say that π is H-admissible. Let Pg,n : Ω → h* denote the restriction map. My objective is to show the following conjecture due to Michel Duflo : 1. The representation π i s H-admissible if and only if the moment application Pg,n is proper on the image. 2. If π is H-admissible, and if T is a discrete series of H then it s multiplicity in the restriction of π to H must be calculated by « quantifying » the corresponding reduced space (that is compact in this case). In this thesis, we provide a positive response to this conjecture in two situations, namely when: (i) G is exponential solvable Lie group. (ii) G is the semi direct product of a compact torus and the Heisenberg group and H is a connected algebraic subgroup.
8

Sur les barrières des systèmes non linéaires sous contraintes avec une application aux systèmes hybrides / On Barriers in Constrained Nonlinear Systems with an Application to Hybrid Systems

Esterhuizen, Willem 18 December 2015 (has links)
Cette thèse est consacrée à l'étude de la théorie des barrières pour les systèmes non linéaires sous contraintes d'entrées et d'état. La principale contribution concerne la généralisation au cas de contraintes mixtes, c'est-à-dire dépendant des entrées et de l'état de façon couplée. Ce type de contraintes apparaît souvent dans les applications et dans les systèmes différentiellement plats sous contraintes. On prouve un théorème du type principe du minimum qui permet de construire la barrière et l'ensemble admissible associé. De plus, dans le cas d'intersection de plusieurs trajectoires ainsi construites, on démontre que les points intersections transversaux sont des points d'arrêt de la barrière. Ces résultats sont utilisés pour calculer l'ensemble admissible d'un pendule inversé avec un câble non-rigide monté sur un chariot, la contrainte correspondant au fait que le câble reste tendu. Ce problème correspond en fait à la détermination de l'ensemble potentiellement sûr dans le cadre des systèmes hybrides. / This thesis deals with the theory of barriers in input and state constrained nonlinear systems. Our main contribution is a generalisation to the case where the constraints are mixed, that is they depend on both the input and the state in a coupled way. Constraints of this type often appear in applications, as well as in constrained flat systems. We prove a minimum-like principle that allows the construction of the barrier and the associated admissible set. Moreover, in case of intersection of some of the trajectories involved in this principle, we prove that such transversal intersection points are stopping points of the barrier.We demonstrate the utility of all the theoretical contributions by finding the admissible set for the inverted pendulum on a cart with a non-rigid cable, the constraint being that the cable remains taut. Note that this problem corresponds to the determination of potentially safe sets in hybrid systems.
9

Tipping the scales : the reduction of procedural protection for the accused in inter-jurisdictional cases

Nash, Susan January 2000 (has links)
Within mature criminal justice systems there exists a range of procedural mechanisms designed to provide the accused with protection from unlawful and unfair treatment by prosecuting authorities. Whilst some systems insist on judicial involvement in the investigation of crime, others grant the court discretionary powers to reject evidence or stay proceedings. Complex evidentiary rules flourish in common law systems, whereas civil law systems abide by the principle of the free evaluation of evidence. Judicial responses to the reception of irregularly obtained evidence vary, even within systems sharing a common tradition. Given the strong utilitarian tradition of the English and Scottish courts, judges tend to reason pragmatically rather than articulate principles. Theory and principle relevant to the exclusionary discretion are considered in Chapter 2. The extent of the general powers given to the prosecuting authorities in England and Scotland to gather real evidence, and the range of safeguards designed to protect the rights of suspects are examined in detail in Chapter 3. The fourth Chapter considers the admissibility of irregularly obtained evidence in both jurisdictions and questions whether, and to what extent, the procedural rules permit the court to balance effectively countervailing public interest considerations. The rules operating in France and Germany are examined in outline and used as comparative examples. Police investigative powers do not generally extend beyond the jurisdiction of the national court, thus prosecuting authorities requiring access to evidence located abroad seek assistance through operational police co-operation and mutual legal assistance procedures. These mechanisms are examined in Chapter 5, and consideration given to the differing approaches taken by the English and Scottish courts to the admissibility of regularly and irregularly obtained foreign evidence. The assumption is challenged that evidence obtained abroad can be assessed in the same manner as evidence obtained in breach of national rules without disturbing the fairness of the proceedings. Incorporation of the European Convention on Human Rights has potential for changing the court's response to questions of admissibility and is considered in Chapter 6. This thesis concludes with a critical analysis of the problems identified, and questions whether criminal justice systems can achieve a fair balance without understanding the complex interplay between procedural rules. Only by understanding the function of the procedural rule within each system can the risk of reducing the procedural protection to the accused be avoided. I have endeavoured to state the law as it stood at the end of July 2000.
10

Lie-admissible structures on Witt type algebras and automorphic algebras / Structures Lie-admissibles sur les algèbres de type Witt et les algèbres automorphes

Chopp, Mikaël 29 September 2011 (has links)
L’algèbre de Witt a été intensivement étudiée. Elle est présente dans de nombreux domaines des Mathématiques. Cette thèse est l’étude de deux généralisations de l’algèbre de Witt: les algèbres de type Witt et les algèbres de Krichever-Novikov. Dans une première partie on s’intéresse aux structures Lie-admissibles sur les algèbres de type Witt. On donne toutes les structures troisième-puissance associatives et flexibles Lie-admissibles sur ces algèbres. De plus, on étudie les formes symplectiques qui induisent un produit symétrique gauche. Dans une seconde partie on étudie les algèbres automorphes. Partant d’une surface de Riemann compacte quelconque, on considère l’action d’un sous-groupe fini du groupe des automorphismes de la surface sur des algèbres d’origines géométriques comme les algèbres de Krichever-Novikov. Plus précisément nous faisons le lien entre la sous-algèbre des éléments invariants sur la surface et l’algèbre sur la surface quotient. La structure presque-gradue des algèbres de Krichever-Novikov induit une presque-graduation sur ces sous-algèbres de certaines algèbres de Krichever- Novikov / The Witt algebra has been intensively studied and arise in many research fields in Mathematics. We are interested in two generalizations of the Witt algebra: the Witt type algebras and the Krichever-Novikov algebras. In a first part we study the problem of finding Lie-admissible structures on Witt type algebras. We give all third-power associative Lie-admissible structures and flexible Lie-admissible structures on these algebras. Moreover we study the symplectic forms which induce a graded left-symmetric product. In the second part of the thesis we study the automorphic algebras. Starting from arbitrary compact Riemann surfaces we consider the action of finite subgroups of the automorphism group of the surface on certain geometrically defined Lie algebras as the Krichever-Novikov type algebras. More precisely, we relate for G a finite subgroup of automorphism acting on the Riemann surface, the invariance subalgebras living on the surface to the algebras on the quotient surface under the group action. The almost-graded Krichever-Novikov algebras structure on the quotient gives in this way a subalgebra of a certain Krichever-Novikov algebra (with almost-grading) on the original Riemann surface

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