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Equivalence singulière à la Morita et la cohomologie de Hochschild singulière / Singular equivalence of Morita type and singular Hochschild cohomologyWang, Zhengfang 07 December 2016 (has links)
L’objet de cette thèse est l’étude des catégories singulières des k-algèbres associatives surun anneau commutatif k. On développe la théorie de Morita pour les catégories singulières. Plus précisément, on propose une définition d’équivalence singulière à la Morita avec niveau, qui généralise la notion d’équivalence stable à la Morita introduite par Michel Broué. On montre qu’une équivalence dérivée de type standard induit une équivalence singulière à la Morita avec niveau. La deuxième partie de cette thèse est l’étude de la cohomologie de Hochschild singulière HH_sg(A,A) c’est-à-dire, l’espace des morphismes de A vers A[i] dans la catégorie singulière Dsg(A Aop) pour tous les nombres entiers i. Similaire à la cohomologie de Hochschild HH_(A,A), on montre que la cohomologie de Hochschild singulière HH_sg(A,A) est une algèbre de Gerstenhaber et donne une interprétation pour le crochet de Lie sur HH_sg(A,A) du point de vue de la théorie de PROP. On peut associer un complexe de cochaînes, qu’on appelle complexe de cochaînes de Hochschild singulières, C_sg(A,A) qui calcule la cohomologie de Hochschild singulière HH_sg(A,A). Alors on étudie une structure algébrique supérieure (e.g. l’algèbre de B1) sur C_sg(A,A) et propose une version singulière d’une conjecture de Deligne. L’objet de la troisième partie de cette thèse est de montrer que la structure d’algèbre de Gerstenhaber sur la cohomologie de Hochschild singulière est invariante par équivalences dérivées et équivalences singulières à la Morita avec niveau. L’idée de cette démonstration est analogue à l’approche développée par Keller lorsqu’il démontre que la structure d’algèbre de Gerstenhaber sur la cohomologie de Hochschild est invariante par équivalences dérivées. Similaire à la démonstration par Keller, on réalise HH_sg(A,A) avec le crochet de Lie comme une algèbre de Lie graduée du groupe algébrique gradué associé au groupe de Picard singulière sgDPic(A). / In this thesis, we are concerned with some aspects of singular categories of unitalassociative k-algebras over a commutative ring k. First, we develop a Morita theory for singular categories. Analogous to the classical Morita theory, we propose a definition of singular equivalence of Morita type with level. This follows and generalizes a definition of stable equivalence of Morita type introduced by Michel Broué. A derived equivalence of standard type induces a singular equivalence of Morita type with level. Second, we study the Hom-space from A to A[i] in the singular category Dsg(AkAop) of the enveloping algebra AkAop, where A is an associative k-projective k-algebra and i is any integer. Recall that the i-th Hochschild cohomology group HHi(A,A) can be realized as the Hom-space from A to A[i] in the bounded derived category Db(A k Aop). From this motivation, we call HomDsg(AkAop)(A,A[i]) the i-th singular Hochschild cohomology group and denote this group by HHi sg(A,A). Analogous to the Hochschild cohomology ring HH_(A,A), we prove that there is a Gerstenhaber algebra structure on the singular Hochschild ring HH_sg(A,A) and provide an interpretation of the Lie bracket from the point of view of PROP theory. We also associate a cochain complex, which we call singular Hochschild cochain complex, C_sg(A,A) to the singular Hochschild cohomology. Thenwe study the higher algebraic structures (e.g. B1-algebra) on C_sg(A,A) and propose asingular version of the Deligne conjecture. Following Keller’s approach which was developed for derived equivalences, we establish the invariance of the Gerstenhaber algebra structure which we defined on the singular Hochschild cohomology under singular equivalence of Morita type with level. In this proof, we define the singular derived Picard group sgDPic(A) of an associative algebra A and develop what we call a singular infinitesimal deformation theory. Then we realize HH_sg(A,A) as the graded Lie algebra of the ‘graded algebraic group’ associated to sgDPic(A).
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Quelques propriétés de rigidité des algèbres de von Neumann / Some Rigidity Properties of von Neumann AlgebrasMarrakchi, Amine 06 June 2018 (has links)
Dans cette thèse, je m'intéresse à diverses propriétés de rigidité des algèbres de von Neumann. Dans le Chapitre 1, je démontre la solidité relative des produits croisés issus d'actions Bernoulli de type quelconque. Ce résultat repose sur la théorie de la déformation/rigidité de Popa et généralise un théorème de Chifan et Ioana en type II. Comme conséquence, dès que le groupe qui agit est non-moyennable, ces produits croisés sont premiers (n'admettent pas de décomposition non triviale en produit tensoriel de deux facteurs) et la relation d'équivalence associée est solide. Le Chapitre 2 a pour thème les facteurs pleins et les phénomènes de trous spectraux. Je montre notamment que tout facteur plein de type $III$ vérifie une propriété de trou spectral similaire à celle obtenue par Connes dans le cas II_1. Le trou spectral permet d'analyser plus finement la structure de ces facteurs et de leur groupe d'automorphismes. Je généralise ainsi un théorème de Jones en donnant une condition suffisante pour qu'un produit croisé soit plein. Cette condition est de plus nécessaire dans le cas où le groupe qui agit est abélien. Ceci permet de caractériser complètement les facteurs de type III_1 dont le cœur est plein. Dans un travail en collaboration avec C. Houdayer et P. Verraedt, nous montrons aussi qu'un produit tensoriel de deux facteurs pleins est encore plein et nous calculons ses invariants de Connes. Nous obtenons aussi un théorème d'unique décomposition McDuff qui généralise un résultat de Popa dans le cas II_1.Dans le Chapitre 3, je m'intéresse aux facteurs McDuff, i.e. qui ont la propriété d'absorber tensoriellement le facteur hyperfini, ainsi qu'à leur analogue en théorie ergodique, les relations d'équivalences stables. Je donne notamment une nouvelle caractérisation de cette propriété de stabilité qui repose sur un argument de maximalité. Cette caractérisation de type "trou spectral", plus fine que celle connue jusqu'alors, permet de démontrer le résultat de rigidité suivant: un produit direct de deux relations d'équivalences est stable si et seulement si l'une des deux est stable. Le problème similaire pour les facteurs McDuff reste ouvert, mais je donne quelques résultats partiels. / In this dissertation, I study several rigidity properties of von Neumann algebras. In Chapter 1, we prove the relative solidity of Bernoulli crossed products of arbitrary type. This result is based on Popa's deformation/rigidity and generalizes a theorem of Chifan and Ioana in the tracial case. As a consequence, when the acting group is non-amenable, the crossed product is prime (cannot be decomposed nontrivially as a tensor product of two factors) and the associated equivalence relation is solid.In Chapter 2, we study full factors in relation with the spectral gap property. The main result is a spectral gap characterization of full type III factors which is similar to Connes' characterization in the tracial case. This allows us to better understand the structure of these factors and their automorphism group. We generalize a theorem of Jones by giving a sufficient condition for a crossed product to be full. This condition is necessary when the group is abelian. In particular, we obtain a complete characterization of the type III_1 whose core is full. In a joint work with C. Houdayer and P. Verraedt, we show that a tensor product of two full factors is also full and we compute its Connes invariants. We also prove a unique McDuff decomposition theorem that generalizes a result of Popa in the II_1 case. In Chapter 3, we study McDuff factors, i.e. those factors that can absorb tensorially the hyperfinite factor, as well as their counterpart in ergodic theory, the so-called stable equivalence relations. We obtain a new "spectral gap like" characterization of these properties, based on a maximality argument. With this refined characterization, we are able to prove the following rigidity result: a direct product of two stable equivalence relations is stable if and only if one of them is already stable. The analoguous problem on McDuff factors remains open, but we do give some partial results.
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Interférométrie Simultanée avec Deux Espèces Atomiques ⁸⁷Rb/⁸⁵Rb et Applications aux Mesures Inertielles / Simultaneous Interferometry with Two Atomic Species ⁸⁷Rb/⁸⁵Rb and Applications to Inertial MeasurementsBonnin, Alexis 23 November 2015 (has links)
Dans la problématique émergente des expériences visant à tester le Principe d'Équivalence à l'aide de capteurs inertiels à atomes froids, cette thèse porte sur la réalisation et la caractérisation d'un interféromètre atomique double espèce simultané (⁸⁷Rb et ⁸⁵Rb) qui permet l'obtention d'une mesure extrêmement sensible de l'accélération différentielle. L'interféromètre, de type Mach-Zehnder, repose sur la manipulation simultanée des ondes de matière atomiques à l'aide de transitions Raman stimulées. Le système laser est basé sur le doublage en fréquence d'une unique source laser à 1560 nm. L'ensemble des fréquences lasers requises pour la manipulation des deux isotopes (piégeage, refroidissement, sélection, interférométrie et détection) sont générées par modulation en phase de cette source. Une modélisation détaillée des réponses inertielles de l'interféromètre ainsi que l'analyse d'une méthode d'extraction de la phase différentielle à partir du signal elliptique ont été menées. La mesure de l'accélération différentielle a conduit à un test atomique du Principe d'Équivalence Faible de η(⁸⁷Rb,85Rb) = (1.3 ± 3.2) × 10⁻⁷, à l'état de l'art. L'aspect simultané de la mesure a permis de mettre en évidence la réjection du bruit de vibration par effet de mode commun pour la première fois avec deux espèces différentes, le facteur de réjection étant aujourd'hui de 50 000. Les performances actuelles de l'instrument sur la mesure d'accélération différentielle montrent une sensibilité de 1.23×10⁻⁷g/√Hz et une résolution de 2×10⁻⁹g pour des temps d'intégration inférieurs à quelques heures. Pour finir, des modes de fonctionnement innovants d'interféromètres atomiques double espèce pour la mesure d'accélération embarquée sont explorés. / In the emerging issue of testing the Equivalence Principle with cold atom inertial sensors, this thesis focuses on the realization and the characterization of a simultaneous dual-species atom interferometer (⁸⁷Rb & ⁸⁵Rb) which allows to measure the differential acceleration in an extremely sensitive way. The Mach-Zehnder type atom interferometer relies on the simultaneous handling of atomic wave-packets with stimulated Raman transitions. The laser system is based on the frequency doubling of a single laser source at 1560 nm. All the required laser frequencies for handling both isotopes (trapping, cooling, selection, interferometry and detection) are generated by phase modulating this source. A detailed modeling of the interferometer's inertial responses and an analysis of a method to extract the differential phase were carried out. The differential acceleration measurement led to an atom based test of the Weak Equivalence Principle of η(⁸⁷Rb,85Rb) = (1.3 ± 3.2)×10⁻⁷, at the state-of-the-art. The simultaneous aspect of the experiment allowed to highlight for the first time common mode vibration noise rejection with two different atomic species, a rejection factor of 50 000 being currently achieved. The current performance of the instrument exhibits a sensitivity on the differential acceleration of 1.23 × 10⁻⁷g/√Hz and a resolution of 2 × 10⁻⁹g for integration times lower than few hours. Finally, innovative operating modes of dual-species atom interferometers for on-board acceleration measurements are explored.
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Využití přibližné ekvivalence při návrhu přibližných obvodů / Employing Approximate Equivalence for Design of Approximate CircuitsMatyáš, Jiří January 2017 (has links)
This thesis is concerned with the utilization of formal verification techniques in the design of the functional approximations of combinational circuits. We thoroughly study the existing formal approaches for the approximate equivalence checking and their utilization in the approximate circuit development. We present a new method that integrates the formal techniques into the Cartesian Genetic Programming. The key idea of our approach is to employ a new search strategy that drives the evolution towards promptly verifiable candidate solutions. The proposed method was implemented within ABC synthesis tool. Various parameters of the search strategy were examined and the algorithm's performance was evaluated on the functional approximations of multipliers and adders with operand widths up to 32 and 128 bits respectively. Achieved results show an unprecedented scalability of our approach.
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Efektivní algoritmy pro stromové automaty / Efficient Algorithms for Tree AutomataValeš, Ondřej January 2019 (has links)
In this work a novel algorithm for testing language equivalence and inclusion on tree automata is proposed and implemented as a module in the VATA library. First, existing approaches to equivalence and inclusion testing on both word and tree automata are examined. These existing approaches are then modified to create bisimulation up-to congruence algorithm for tree automata and a formal proof of the soundness of the new algorithm is provided. Efficiency of this new approach is compared with existing language equivalence and inclusion testing methods for tree automata, showing the performance of our algorithm on hard cases is often superior.
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Kvalitet på skam : en kvalitetsundersökning av fansubs i tv-serien SKAM / Quality of shame : a quality assessment study on fansubs in the tv-series SKAM (Shame)Kaufner, Anna January 2020 (has links)
Undertexter skapade av fans, så kallade fansubs, utmärker sig ofta med att utmana de standardiserade normerna inom undertextning genom att vara friare från deras inflytande. En serie som det har skapats relativt mycket fansubs för är den norska webbaserade ungdomsserien SKAM, som fans började skapa egna undertexter till eftersom de ville göra serien mer tillgänglig för tittare från andra länder. Syftet med denna uppsats är att utföra en kvalitetsundersökning av två engelskspråkiga fansub-versioner till tv-serien SKAM. Undersökningen utfördes med hjälp av FAR-modellen, som är en modell skapad för kvalitetsanalys av mellanspråkliga undertexter. FAR-modellen bedömer kvaliteten på undertexter i tre olika områden: funktionell ekvivalens, acceptans och läsbarhet. Undersökningens resultat visar att kvaliteten på fansubs till SKAM är jämförbar med andra fansubs. Kvaliteten varierar dock en del inom de olika områdena, då båda versionerna fick sämst resultat inom läsbarhet, men presterade relativt bra inom funktionell ekvivalens och acceptans. / Subtitles created by fans, so called fansubs, are known to often challenge standardized norms in translation by being freer from their influence. A TV series that many fansubs have been created for is SKAM, the Norwegian web-based series aimed at teens, which fans started creating their own subtitles for because they wanted to make it more accessible to viewers from other countries. The aim of this paper is to carry out a quality assessment study of two English fansub versions for the TV series SKAM. The study was carried out with the help of the FAR model, a model that was created for assessing the quality of interlingual subtitles. The FAR model investigates quality in three different areas: functional equivalence, acceptability and readability. The results of the study show that the quality of the fansubs for SKAM is comparable to that of other fansubs. However, the quality varies somewhat between the different areas, as both versions had the lowest results in readability, but performed better in functional equivalence and acceptability.
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Comparing the measurement of subjective health related quality of life between migrant and native populationsMayerl, Jochen, Holz, Manuel 18 February 2020 (has links)
Measurement problems in terms of different understanding of the meaning, concepts and implications of survey questions as well as tendencies to different response-sets (e.g. acquiescence or social desirability) are reoccurring problems in comparative migration research. Cultural factors, time-varying effects and survey design lead to response biases. It could be shown that depending on the region of origin, migrants tend to extreme or centred responding behaviour. Macroscale changes in attitudes towards disclosure of personal information influence acquiescent biases. Therefore, the question arises whether the presence of measurement equivalence can be assumed, especially within instruments regarding subjective feelings, when comparing migrant and native populations.
The aim of the study is to test for intercultural and longitudinal equivalence of the Health Short Form 12 - items scale (SF -12), trying to answer the question whether this instrument is useful to compare health of migrants and native Germans over time. The study contributes to the ongoing discussion on measurement equivalence of the SF -12 by including variables concerning integration and assimilation, employment, family status and varying types of migration and years since migration to the analysis.
Using a Multiple Group Structural Equation Modelling approach analyzing longitudinal data of the German Socioeconomic Panel (SOEP), we test the validity and measurement equivalence (configural, metric and scalar invariance) of the latent construct ‘health’ over time and between (non-)migration groups. In addition, different item functioning can be detected for a series of covariates. The study concludes in recommending a reduced version of the SF-12 to improve the avoidance of measurement artefacts when comparing the health of migrants and native Germans.
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Influence of Rotation on the Weight of Gyroscopes as an Explanation for Flyby AnomaliesTajmar, Martin, Assis, Andre Koch Torres January 2016 (has links)
We consider two models which lead to the prediction of a weight change of gyroscopes depending on the rate of rotation: mass-energy equivalence and Weber's force for gravitation. We calculate the order of magnitude of this effect in both models and show that Weber's model predicts a weight change depending on the spin axis orientation resembling close similarities to observed Earth flyby anomalies. however, our predicted effect is much smaller than the observed effect, which could explain why flyby anomalies were not detected anymore in recent spracecraft trajectories.
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Bázové posloupnosti v Banachových prostorech / Basic sequences in Banach spacesZindulka, Mikuláš January 2021 (has links)
An ordering on bases in Banach spaces is defined as a natural generalization of the notion of equivalence. Its theory is developed with emphasis on its behavior with respect to shrinking and boundedly-complete bases. We prove that a bounded operator mapping a shrinking basis to a boundedly-complete one is weakly compact. A well-known result concerning the factorization of a weakly compact operator through a reflexive space is then reinterpreted in terms of the ordering. Next, we introduce a class of Banach spaces whose norm is constructed from a given two-dimensional norm N. We prove that any such space XN is isomorphic to an Orlicz sequence space. A key step in obtaining this correspondence is to describe the unit circle in the norm N with a convex function ϕ. The canonical unit vectors form a basis of a subspace YN of XN . We characterize the equivalence of these bases and the situation when the basis is boundedly-complete. The criteria are formulated in terms of the norm N and the function ϕ. 1
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Forcing, deskriptivní teorie množin, analýza / Forcing, deskriptivní teorie množin, analýzaDoucha, Michal January 2013 (has links)
The dissertation thesis consists of two thematic parts. The first part, i.e. chapters 2, 3 and 4, contains results concerning the topic of a new book of the supervisor and coauthors V. Kanovei and M. Sabok "Canonical Ramsey Theory on Polish Spaces". In Chapter 2, there is proved a canonization of all equivalence relations Borel reducible to equivalences definable by analytic P-ideals for the Silver ideal. Moreover, it investigates and classifies sube- quivalences of the equivalence relation E0. In Chapter 3, there is proved a canonization of all equivalence relations Borel reducible to equivalences de- finable by Fσ P-ideals for the Laver ideal and in Chapter 4, we prove the canonization for all analytic equivalence relations for the ideal derived from the Carlson-Simpson (Dual Ramsey) theorem. The second part, consisting of Chapter 5, deals with the existence of universal and ultrahomogeneous Polish metric structures. For instance, we construct a universal Polish metric space which is moreover equipped with countably many closed relations or with a Lipschitz function to an arbitrarily chosen Polish metric space. This work can be considered as an extension of the result of P. Urysohn who constructed a universal and ultrahomogeneous Polish metric space.
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