Le moteur à reluctance commutée (SRM) est connu pour sa conception simple, sans aimants permanents, bobinage au rotor et son bas cout de production et une bonne robustesse qui lui confère conception, même sous la perte d’une phase ou de plus et d’opérer dans un environnement industriel très contraignant. Néanmoins ce moteur présente de nombreux inconvénients due à sa double saillance polaire, ses caractéristiques magnétiques et un couple de sortie hautement non linéaires très instable et qui présente de fortes perturbations. La double saillance du moteur ne permettant pas d’exciter ce dernier par une alimentation CA conventionnelle et de commander ce moteur utilisant la théorie des champs tournants. En outre, en raison des caractéristiques de sortie de couple non linéaires du moteur, une ondulation à couple élevé est inhérente au moteur, sauf si une stratégie de réduction de l’ondulation de couple est utilisée. Afin de parer à la non linéarité du couple de sortie et de diminuer les fortes perturbations de couple, plusieurs techniques ont été utilisées. La technique de contrôle du couple direct (DTC) est une excellente technique qui a donné de bons résultats pour ce type de moteur, et pour ce faire notre travail peut être considérée comme une contribution à l’amélioration de la DTC. Nous considérons spécifiquement le remplacement des régulateurs à hystérésis par ceux utilisant les techniques d’intelligence artificielle (logique floue, réseaux de neurones et neuro-flou), avec une concentration plus prononcée pour la technique de régulation par logique floue avec une structure Takagi-Sugeno comme le cœur de notre travail. Pour finir, nous avons utilisé la commande adaptative pour varier les paramètres du régulateur flou en temps réel lors de perturbations paramétriques du SRM et notamment pour parer à la variation de la résistance statorique. La loi de contrôle et la loi adaptative développées, garantissent que tous les signaux dans le système en boucle fermée sont limités en amplitude, alors que la conception du contrôleur est basée sur la synthèse de Lyapunov. / Switched Reluctance (RS) Motors have an intrinsic simplicity and low cost that makethem well suited to many applications. Furthermore, the motors have a high robustness due to the ability to operate with the loss of one or more motor phases and are thus well suited to operate in harsh industrial environments. However, the motor has many drawbacks due to the motor’s doubly salient structure as well as highly non-linear torque output and magnetization characteristics. The double salient structure leads to the inability to excite the motor using conventional ac motor rotating field theory to the motor. Furthermore, due to the motor’s non-linear torque output characteristics, a hightorque ripple is inherent in the motor unless a torque ripple reduction strategy is employed. to overcome the non-linearity of the output torque and reduce torque ripple,several techniques have been developed. Direct torque control (DTC) is an excellent technique which has had good results for this type of motor. our work, is a contribution to the improvement of the DTC by the substitution of the hysteresis regulators by thoseusing artificial intelligence techniques (fuzzy logic, neural networks and neuro-fuzzy), with a more pronounced concentration in our study for fuzzy logic regulation technique with Takagi-Sugeno structure. Finally, we used the adaptive control to vary the fuzzy regulator parameters in real time during parametric disturbance of the SRM and especially during stator resistance variation. The control law and the adaptive law developed guarantee the delimitation of all the signals in the closed-loop system and the controller design is made according to Lyapunov's synthesis

Les plateformes numériques de travail construisent leur modèle économique à l’écart des règlementations traditionnellement applicables aux secteurs d’activités dans lesquelles elles évoluent (par exemple, le transport privé de personnes), au premier rang desquelles figure le droit du travail. Au motif qu’elles ne seraient que des intermédiaires entre une offre et une demande, la qualification de travailleur salarié (parfois même, de travailleur tout court) est niée. On lui préfère l’indépendance supposée par le recours aux contrats civils et commerciaux. Les travailleurs des plateformes ne peuvent alors pas leur opposer le respect du droit social (ex : droit du licenciement, droit de négociation collective, congé maternité, assurance chômage, etc.). Pourtant, dès lors qu’une organisation développe une activité économique et commerciale qui suppose le recourt à des contrats portant sur la force de travail pour en permettre le développement, il est difficile d’affirmer l’absence de travail comme l’indépendance. Les plateformes de travail ne sont pas de simples plateformes d’intermédiation, mais des organisations productives s’inspirant bien plus que les entreprises des logiques de concurrence qui gouvernent le marché. La remise en cause de la législation sociale qu’elles provoquent s’inscrit dans une vision déterministe du droit du travail qui prétend que le droit doit nécessairement s’adapter aux exigences formulées par l’économie. En aucun cas cependant, le droit du travail se trouve dépourvu de réponse face à ces nouveaux modèles. Au contraire, les perturbations qu’ils provoquent font écho à l’histoire même de sa construction, invitant au-delà du droit français, le droit social européen et international, à affirmer ses exigences et ses ambitions. / Digital employment platforms build their business model away from the scope of regulations that would traditionally apply to their line of business (for example, private passenger transport companies), the first of which is labour law. It is argued they serve as mere intermediaries between demand and supply, and as such, the status of employee (and sometimes of a worker altogether) is denied. Instead, preference is given to presumed independence via civil and commercial contracts. As a consequence, individuals working for these platforms are not protected by labour law (ex: termination of employment regulation, collective negotiation rights, maternity leave, unemployment benefits, etc.).Yet, when an organisation develops a commercial and economic activity entailing the use of contracts depending on labour power as its very basis for existence, it is difficult to affirm absence of labour or independence. Employment platforms are not mere intermediation platforms; rather, they are productive entities which draw their dynamics from competitive patterns on the market, far more than traditional firms would.The calling into question of social law they spark is part and parcel of a determinist vision of labour law, which claims that law must necessarily adapt to economy’s requirements. This in no way means that law is helpless in the face of these new models. Quite the contrary, the disrupt they bring forward reflects the history of law’s very construction, for French but also European and international law, and calls for it to reassert its demands and ambitions.

Pas de résumé

Pas de résumé

Thèse--Droit--Paris 2, 1975. / Bibliogr. p. 15-39. Index.

Extr. remanié de: Thèse--Lettres--Lille III, 1983. / Bibliogr. p. 237-270. Index.

Thesis (M.A.)--Trinity Evangelical Divinity School, 1992. / Abstract. Includes bibliographical references (leaves 141-161).

En 1969 s’ouvrent à New York les premiers espaces alternatifs, dans les anciens quartiers industriels du sud de Manhattan, appelés à se transformer radicalement durant la décennie suivante. Lieux d’exposition, de création et de réunion établis en marge des institutions muséales et des galeries commerciales, ils cristallisent l’existence de groupes et de collectifs d’artistes se rassemblant autour de pratiques et de revendications communes. Sur le plan des pratiques, on observe une interdisciplinarité généralisée, mêlant poésie, danse, sculpture, film, vidéo, performance, architecture et musique. Sur le plan des revendications, l’heure est à la politique, et les artistes, souvent engagés dans les luttes sociales qui agitent les Etats-Unis à cette époque, réclament une certaine reconnaissance, un droit du travail qui leur soit applicable, et une intégration concrète dans la société civile et économique. L’objet de notre recherche est d’apporter une nouvelle approche de ce phénomène, une histoire sociale et géographique des pratiques artistiques dans les espaces alternatifs de cette époque, en mettant en lumière l’articulation entre ces pratiques et les phénomènes institutionnels, sociaux, économiques et urbains dont elles ne peuvent être dissociées. Une telle approche conduit notamment à analyser la relation étroite existant entre les œuvres et pratiques artistiques et la matière urbaine, la topographie et les caractéristiques architecturales de Downtown Manhattan. Elle met aussi en relief les interactions entre l’alternative et les institutions traditionnelles, qui conduiront à des redéfinitions a posteriori de la notion même d’espace alternatif. / In 1969 the first alternative art spaces opened in New York in the old industrial neighborhoods of downtown Manhattan which would undergo radical transformation in the decade that followed. Established in the margins of museum institutions and commercial galeries, these exhibition, creation, and meeting spaces crystallized the existence of artists’ groups and collectives organizing around common practices and demands. The practices exhibit a general interdisciplinarity combining poetry, dance, sculpture, film, video, performance, architecture,and music. The demands are clearly political and the artists, many of whom involved in the social movements that engage the United States at the moment, are calling for recognition, a right to work applicable and appropriate to them, as well as concrete integration into civil and economic society. The object of this study, a social and geographic history of artistic practices in the alternative art spaces of this moment, is to bring to light the articulations between these practices and the institutional, social, economic, and urban phenomena from which they cannot be dissociated. Such an approach leads notably to an analysis of the close relation between the artistic works and practices and the urban material, the topography and the architectural characteristics of downtown Manhattan. This approach also foregrounds the interactions between the alternative art scene and mainstream institutions which lead to posteriori redefinitions of the notion of alternative art space itself.

Made available in DSpace on 2018-08-01T22:56:53Z (GMT). No. of bitstreams: 1 tese_7579_FABIANA MARIA DO AMARAL BRAVO20140409-132729.pdf: 916946 bytes, checksum: 5240e7e967f42c029d340d1e4ad21701 (MD5) Previous issue date: 2014-02-21 / A fasciolose bovina produz danos graves ao fígado e é causada pelo parasito Fasciola hepatica. Objetivou-se caracterizar as alterações morfológicas e histoquímicas do tecido hepático em bovinos com fasciolose crônica, bem como, identificar os focos de metaplasia. Foram coletados 47 fígados de bovinos condenados por fasciolose e 12 fígados normais utilizados para controle, no matadouro frigorífico de Atílio Vivacqua, ES. Foi feita a contagem de parasitos e coleta de cinco fragmentos de cada lobo, direito e esquerdo, dos fígados acometidos pela enfermidade, totalizando 235 amostras por lobo. O grupo controle foram coletados apenas um fragmento por fígado. Todo material foi fixado em formol a 10% e submetido ao processamento histológico e coloração por HE e PAS. Foi feita a análise microscópica com base na distribuição da fibrose em graus 1, 2 e 3 e no tipo e intensidade do infiltrado inflamatório, seguida da avaliação dos focos de metaplasia. A avaliação estatística foi feita pelo método descritivo e pelo teste de Mann-Whitney com 5% de probabilidade. Não foi verificada diferença entre o número de parasitos por lobo hepático, porém o lobo esquerdo apresentou maior intensidade parasitária. A fibrose foi observada em todas as amostras prevalecendo a de grau 1. Houve diferença significativa entre fígados com F. hepatica e fígados normais quanto ao grau de fibrose, tanto para o lobo direito quanto para o esquerdo e entre estes. O infiltrado inflamatório revelou predominância de células mononucleadas de intensidade discreta. Houve diferença entre a intensidade do infiltrado inflamatório entre os lobos direito e esquerdo do fígado. A presença de eosinófilos também foi verificada, porém em menor quantidade. Em relação aos focos de metaplasia observou-se que 53,19% das amostras do lobo direito apresentaram estas 8 alterações enquanto que, no lobo esquerdo, este percentual foi de 57,45%, entretanto, não foram encontradas diferenças significativas entre a ocorrência de metaplasia entre os lobos direito e esquerdo. Foi observada maior prevalência de produção de muco em intensidade discreta e moderada, no entanto, não houve diferença entre a quantidade de muco produzida entre os lobos hepáticos. Conclui-se que a fibrose é alteração mais marcante em fígados cronicamente infectados por F. hepatica sendo mais evidente no lobo hepático esquerdo. O infiltrado inflamatório foi predominantemente mononuclear e discreto e também mais prevalente no lobo esquerdo. Os focos de metaplasia estão presentes nos fígados com fasciolose crônica e possuem diferença na intensidade de muco produzido.

Secondary metabolites play important roles in tree defense. Proanthocyanidins (PAs), one of the most common secondary metabolites, are widely distributed in trees and woody plants, and are abundant in poplar. In my research, molecular biology and biochemistry techniques were used to investigate the function of two important transcription factors, MYB115 and MYB134, in regulating the PA pathway in hybrid poplars. The importance of these transcription factors in regulating PA synthesis in leaves has recently emerged, but their roles in roots are not known. MYB134- and MYB115-overexpressing transgenic poplars showed a strong high-PA phenotype in leaves, but how these two regulators interact in vivo is still a mystery. This research aims to test the function of both MYBs in the regulation of PAs in poplar roots, and to explore the antimicrobial functions of root PAs. Both alleles of the MYB genes were sequenced in wild type poplars to design gRNAs for creating transgenic poplars with knocked-out (KO) MYB115 and MYB134 using the CRISPR Cas9 system. Both hairy root and whole plant transgenics with respective single- and double knock-outs were generated. Chemical and genetic characterization of both mutant types showed reduced PA content and down-regulated flavonoid genes in leaves. In poplar roots, only double-KOs showed a significant change in PA and salicinoid metabolism. These results indicated that the regulatory pathways for PA biosynthesis may differ in poplar leaves and roots. Significant PA concentrations remained in double-KO plants, suggesting other transcription factors for PA regulation are active. Because poplars accumulate large amounts of PAs in roots, potential functions of root tannins were also investigated. Antimicrobial activity of PAs was tested by disc inhibition assay in vitro and mycorrhizal co-culture sandwich assay in vivo. Pure PAs showed no inhibition towards the pathogenic fungi Armillaria ostoyae and A. sinapina but displayed slight inhibition to the mycorrhiza fungus Laccaria bicolor. These results provide preliminary insight into the functions of PAs in roots. / Graduate / 2023-04-24