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Lodi, Cesar Augusto. "OS MÉTODOS DE EXTENSÃO RURAL EMPREGADOS PELA EPAGRI NO ALTO VALE DO ITAJAÍ - SC." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/8895.
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Rural Extension in Brazil has passed through many transformations in its way of acting and developing the work with farmers. The extension methods are extremely related to these transformations and, in a large extent, since the creation of the official services of Rural Extension, they arethe identity of the extensionist institutionsworker in the country.This study has analyzed the use of different methods of rural extension by the Empresa de Pesquisa de Agropecuária e Extensão Rural Santa Catarina (Epagri). The research was developed through the case study of the Unidade de GestãoTécnica 5, composed by 31 cities, located in the region called Alto Vale do Itajaí SC, with a cuali-quantative approach.The results point out that, in relation to the nature of the work done by extensionists, there is a predominance of office activities over field work, determined, mainly, by the demand of the paper work generated by governmental programs. The data demonstrated that about 50% of the farmers and 40% of the actions developed are associated to back activities, showing that a big part of the technician`s effort is associated to the demand of governmental programs. Considering the nature of the work methods, it was founda predominance of individual approach technics, they constitute 94.54% of the activities unfolded, existing among them a predominance of the office visiting. According to the technicians‟ point of view, the predominance of the individual approach is related to the nature of the work that they do and, the changes implemented in the Epagri managementdid not produced the expected effects in the increasing use of group methods.A Extensão Rural no Brasil tem passado por diversas transformações na sua forma de atuar e desenvolver o trabalho junto aos agricultores. Os métodos de extensão guardam estreitas relações com essas transformações e em grande medida continuam sendo, desde a criação dos serviços oficias de Extensão Rural, a identidade do trabalhador das instituições extensionistas no país. Este estudo analisou o emprego dos diferentes métodos de extensão rural pela Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina (Epagri). A pesquisa foi desenvolvida a partir do estudo de caso da Unidade de Gestão Técnica 5, composta por 31 municípios, situada na região denominada Alto Vale do Itajaí - SC, com uma abordagem quali-quantitativa. Os resultados apontam que, em relação à natureza do trabalho desenvolvido pelos extensionistas, ocorre um predomínio das atividades de escritório sobre o trabalho de campo, determinado em grande medida pela demanda do trabalho burocrático gerado pelos programas governamentais. Os dados demonstraram que praticamente 50% dos agricultores e 40% das ações desenvolvidas vinculam-se às atividades de apoio, apontando que grande parte do esforço dos técnicos está relacionada com as demandas dos programas governamentais. Em relação à natureza dos métodos de trabalho, constatou-se um predomínio absoluto das técnicas de abordagem individual, que constituem 94,54% das atividades realizadas, havendo entre elas uma ampla predominância dos atendimentos no escritório. Na visão dos técnicos, o predomínio dos métodos de abordagem individual está relacionado à natureza do trabalho que desenvolvem e as mudanças implantadas na gestão da Epagri não surtiram os efeitos desejados no aumento do emprego de métodos de caráter grupal.
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Eckhardt, Adam A. "Analysis and extension of the renormalization group treatment of fluid turbulence." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ49939.pdf.
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Renshaw, James Henry. "Flatness, extension and amalgamation in monoids, semigroups and rings." Thesis, University of St Andrews, 1986. http://hdl.handle.net/10023/11071.
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We begin our study of amalgamations by examining some ideas which are well-known for the category of R-modules. In particular we look at such notions as direct limits, pushouts, pullbacks, tensor products and flatness in the category of S-sets. Chapter II introduces the important concept of free extensions and uses this to describe the amalgamated free product. In Chapter III we define the extension property and the notion of purity. We show that many of the important notions in semigroup amalgams are intimately connected to these. In Section 2 we deduce that 'the extension property implies amalgamation' and more surprisingly that a semigroup U is an amalgamation base if and only if it has the extension property in every containing semigroup. Chapter IV revisits the idea of flatness and after some technical results we prove a result, similar to one for rings, on flat amalgams. In Chapter V we show that the results of Hall and Howie on perfect amalgams can be proved using the same techniques as those used in Chapters III and IV. We conclude the thesis with a look at the case of rings. We show that almost all of the results for semi group amalgams examined in the previous chapters, also hold for ring amalgams.
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Wibberley, E. John. "The farmer - dominant study group : a practical paradigm in international extension strategy." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333655.
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Edmundo, Mario Jorge. "O-minimal expansions of groups." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312447.
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Lane, Steven. "The extension of multivariate statistical process performance monitoring techniques to multiple group applications." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310031.
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Jarl, Timmy. "On Completion of Modules and the Abelian Group Formed from Extension of Modules." Thesis, Uppsala universitet, Algebra och geometri, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-297711.
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Salami, Azar. "Construction of basis of the group of cyclotomic units of some real abelian extension." Doctoral thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/25460.
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Dans cette thèse, nous construisons une base du groupe Ck des unités cycolotomiques (au sens de Sinnott) d’une certaine extension abélienne finie k de Q ramifiée exactement sur trois nombres premiers distincts. La première étape consiste en la construction d’une base du goupe Dk des nombres circulaires de k. Par la suite, il sera plus simple d’obtenir une base de Ck.In this thesis, we construct an explicit basis of the group Ck of cyclotomic units of certain finite abelian extension k of Q ramified at exactly three distinct primes. The first step consists in constructing a basis of the group Dk of circular numbers of k. From there, it is not too difficult to obtain a basis of Ck. The method is combinatorial in nature. We may visualize our construction using a three dimensional cuboid formed of j Gal(k=Q)j small cubes, each of these small cubes containing a Galois conjugate of a primitive circular unit of k. The classical norm relations give rise to some identifications on the cuboid. Using these identifications and an Ennola-type relation (a highly non-trivial relation), we manage to construct an explicit basis of Ck.
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Ward, Callahan K. "Professional Development Needs of Utah State University Extension Professionals." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/6927.
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Many Utah State University (USU) Extension personnel are nearing retirement age. The purpose of this study was to identify professional development needs of Extension professionals and assess USU Extension by evaluating competencies essential to be a successful Extension professional. USU Extension can conduct more beneficial professional development training by using identified high priority competencies and improve the on boarding process for new Extension professionals. With improvements as suggested, the effectiveness of professional development could be enhanced and produce Extension professionals who work more efficiently and are committed to the success of USU Extension.
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Ajili, Abdulazim School of Fibre Science & Technology UNSW. "Aspects of traditional versus group extension approaches on farmer behavioural change in an extensive grazing environment in the Bathurst District of New South Wales, Australia." Awarded by:University of New South Wales. School of Fibre Science and Technology, 2000. http://handle.unsw.edu.au/1959.4/32906.
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The study on different extension approaches was undertaken in the Bathurst area of New South Wales, Australia. One hundred farmers were surveyed in random pairs according to those who belong to the formal group, ???Landcare???, and those who did not. The survey included questions on personal, physical resources, ecological and economic factors, farm practices and management (including actual practice, use of extension methods and information sources) Focussing on behavioural change over time, attitudes, perceptions and intentions. The impact of extension approach on different levels of innovation was considered: simple (e.g. tree planting), medium (e.g. pasture development) and complex (soil erosion control) on behavioural change. It was hypothesised that the ???group??? extension approach should be more effective with complex innovations, but the main significant differences found were in level of tree planting (higher in government funded Landcare), money spent on erosion control (including tree planting) and attitudes to the severity of local erosion (all higher in Landcare members). There were no other differences in attitudes, intentions or change in farming practice except that non-Landcare farmers planted more pasture and applied more lime. The outcomes did not support the hypothesis, and it was not possible to distinguish the differences that did occur in performance from extension approach versus access to funds. Field days are an important extension method for the adoption of cropping by landholders. Among the different extension methods, those who conducted erosion control through pastures, preferred government officers and meetings. Those who adopted tree planting and were in Landcare preferred magazines as the extension method. This added further weight to the argument that the formal group extension approach may not be perceived by its members to have any influence on adoption at this level. Generally, mass media was more important in the early stages of adoption and personal influence more important in the evaluation stage. This also applied to simple versus complex innovations. Surprisingly all farmers placed a very high reliance on government officers for information and decision-making, particularly those in Landcare, compared to neighbours or family. Formal group extension still needs assessing but using models other than Landcare.
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Monaledi, R. L. "Character tables of some selected groups of extension type using Fischer-Clifford matrices." Thesis, University of the Western Cape, 2015. http://hdl.handle.net/11394/5026.
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>Magister Scientiae - MScThe aim of this dissertation is to calculate character tables of group extensions. There are several well developed methods for calculating the character tables of some selected group extensions. The method we study in this dissertation, is a standard application of Clifford theory, made efficient by the use of Fischer-Clifford matrices, as introduced by Fischer. We consider only extensions Ḡ of the normal subgroup N by the subgroup G with the property that every irreducible character of N can be extended to an irreducible character of its inertia group in Ḡ , if N is abelian. This is indeed the case if Ḡ is a split extension, by a well known theorem of Mackey. A brief outline of the classical theory of characters pertinent to this study, is followed by a discussion on the calculation of the conjugacy classes of extension groups by the method of coset analysis. The Clifford theory which provide the basis for the theory of Fischer-Clifford matrices is discussed in detail. Some of the properties of these Fischer-Clifford matrices which make their calculation much easier, are also given. We restrict ourselves to split extension groups Ḡ = N:G in which N is always an elementary abelian 2-group. In this thesis we are concerned with the construction of the character tables (by means of the technique of Fischer-Clifford matrices) of certain extension groups which are associated with the orthogonal group O+10(2), the automorphism groups U₆(2):2, U₆(2):3 of the unitary group U₆(2) and the smallest Fischer sporadic simple group Fi₂₂. These groups are of the type type 2⁸:(U₄(2):2), (2⁹ : L₃(4)):2, (2⁹:L₃(4)):3 and 2⁶:(2⁵:S₆).
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Zanetti, Janet J. "An extension of dyadic counseling to multi-family group training with application for Head Start families." W&M ScholarWorks, 1996. https://scholarworks.wm.edu/etd/1539618448.
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The purpose of this study was to investigate the effects of one short-term training model, Parents and Children Together (PACT), on parent stress and child behavior for families enrolled in the Head Start program. PACT is a program of structured play activities designed to replicate the interactions between parents and children during the first developmental stage of life. PACT has been adapted, by the researcher, from a program called Theraplay developed for Head Start children by Ann Jernberg (1967).;Thirty families completed the study. Experimental and Control groups were formed from volunteer participants. Only Experimental subjects received training. Sessions were held weekly for one hour on site. Parents and children participated together for the first thirty minutes and parents met without children for the second thirty minutes.;Pre and post treatment assessment with Abidin's Parent Stress Index/Short Form and the Connors' Parent Rating Scale - 48 were administered to each group. The results of this study did not find statistical significance on measures of parent stress and child behavior; however, structured interviews with Experimental subjects indicated high satisfaction with the program.;This study offers an examination of one short term preventive model for community-based mental health services. Implications for multi-disciplinary service delivery are examined.
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Irvin, William D. "Evaluating interdisciplinary extension CRD programming: a case study of commercial vegetable cooperatives." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/77802.
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Extension programming for commercial vegetable cooperatives should be designed to utilize community resource development (CRD) group problem-solving, interdisciplinary educational programming, and an Agricultural Cooperative Service, U.S. Department of Agriculture model for establishing a cooperative. Case study data from three commercial vegetable cooperatives suggest that such programming will increase a cooperative's ability to maximize driving forces and to minimize restraining forces associated with personality and environmental factors operating within the organizational outcome categories of membership commitment, production, administration, management, marketing, and net worth. Both qualitative and quantitative data are used to support the results of the study.Ed. D.
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Hammouri, Hanan. "Review and Extension for the O’Brien Fleming Multiple Testing procedure." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3260.
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O'Brien and Fleming (1979) proposed a straightforward and useful multiple testing procedure (group sequential testing procedure) for comparing two treatments in clinical trials where subject responses are dichotomous (e.g. success and failure). O'Brien and Fleming stated that their group sequential testing procedure has the same Type I error rate and power as that of a fixed one-stage chi-square test, but gives the opportunity to terminate the trial early when one treatment is clearly performing better than the other. We studied and tested the O'Brien and Fleming procedure specifically by correcting the originally proposed critical values. Furthermore, we updated the O’Brien Fleming Group Sequential Testing procedure to make it more flexible via three extensions. The first extension is combining the O’Brien Fleming Group Sequential Testing procedure with the Optimal allocation, where the idea is to allocate more patients to the better treatment after each interim analysis. The second extension is combining the O’Brien Fleming Group Sequential Testing procedure with the Neyman allocation which aims to minimize the variance of the difference in sample proportions. The last extension is that we can allow for different sample weights for different stages, as opposed to equal allocation for different stages. Simulation studies showed that the O’Brien Fleming Group Sequential Testing procedure is relatively robust to the added features.
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Lau, Rebecca S. "Integration and Extension of Leader-Member Exchange and Organizational Justice and Individual- and Group-Levels of Analysis." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/27616.
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Both leader-member exchange (LMX) and organizational justice have commanded a great deal of attention in organizational research. Despite this attention, these two research areas are seldom integrated for examination. This dissertation aimed at helping to integrate these two areas and extend them to a higher level of analysis. Two models were developed at the individual- and group-levels of analysis. In the individual-level model, LMX quality was hypothesized to interact with role breadth self-efficacy (RBSE) and two group characteristics â LMX differentiation and intra-group communication â to impact justice perceptions. It was further hypothesized that justice perceptions would mediate the association between LMX quality and various individual outcomes. In the group-level model, it was hypothesized that LMX differentiation would impact justice climate strength in groups which in turn would affect group-level outcomes. Moreover, justice climate strength was hypothesized to impact these group-level outcomes through two group processes â relationship conflict and team-member exchange (TMX).
Data collected from 413 members constituting 87 groups in a corps of cadets revealed that LMX quality interacted with RBSE, LMX differentiation, and intra-group communication to affect procedural and interactional justice perceptions. In addition, distributive, procedural, and interactional justice perceptions partially mediated the impact of LMX quality on group membersâ commitment to the leader, satisfaction with the leader, job performance, and citizenship behaviors to different degrees. When extended to the group-level of analysis, LMX differentiation in groups was found to lower the strength of distributive, procedural, and interactional justice climates in the groups. These weak justice climates promoted more relationship conflict and hindered social exchange among group members. They also dampened group membersâ commitment to the group, satisfaction with the group, group performance, and citizenship behaviors in the group. Contributions, practical implications, and future directions for research on LMX and organizational justice are discussed.Ph. D.
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Prins, A. L. "Fischer-clifford matrices and character tables of inertia groups of maximal subgroups of finite simple groups of extension type." University of the Western Cape, 2011. http://hdl.handle.net/11394/5430.
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Philosophiae Doctor - PhDThe aim of this dissertation is to calculate character tables of group extensions. There are several well–developed methods for calculating the character tables of group extensions. In this dissertation we study the method developed by Bernd Fischer, the so–called Fischer–Clifford matrices method, which derives its fundamentals from the Clifford theory. We consider only extensions G of the normal subgroup K by the subgroup Q with the property that every irreducible character of K can be extended to an irreducible character of its inertia group in G, if K is abelian. This is indeed the case if G is a split extension, by a well-known theorem of Mackey. A brief outline of the classical theory of characters pertinent to this study, is followed by a discussion on the calculation of the conjugacy classes of extension groups by the method of coset analysis. The Clifford theory which provide the basis for the theory of Fischer-Clifford matrices is discussed in detail. Some of the properties of these Fischer-Clifford matrices which make their calculation much easier are also given. As mentioned earlier we restrict ourselves to split extension groups G in which K is always elementary abelian. In this thesis we are concerned with the construction of the character tables of certain groups which are associated with Fi₂₂ and Sp₈ (2). Both of these groups have a maximal subgroup of the form 2⁷: Sp₆ (2) but they are not isomorphic to each other. In particular we are interested in the inertia groups of these maximal subgroups, which are split extensions. We use the technique of the Fischer-Clifford matrices to construct the character tables of these inertia groups. These inertia groups of 2⁷ : Sp₆(2), the maximal subgroup of Fi₂₂, are 2⁷ : S₈, 2⁷ : Ο⁻₆(2) and 2⁷ : (2⁵ : S₆). The inertia group of 2⁷ : Sp₆(2), the affine subgroup of Sp₈(2), is 2⁷ : (2⁵ : S₆) which is not isomorphic to the group with the same form which was mentioned earlier.
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Gomes, Neila Mara [UNESP]. "Sequências espectrais de Lyndon-Hochschild-Serre e de Cartan-Leray, e algumas aplicações." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/94254.
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gomes_nm_me_sjrp.pdf: 689280 bytes, checksum: e326708cb7096ea2640f86118ab525a2 (MD5)Neste trabalho apresentamos um estudo da sequência espectral associada à uma filtração (finita) de um complexo de cadeias de módulos sobre um anel arbitrário R. Em especial, destacamos as sequências espectrais de Lyndon-Hochschild-Serre e de Cartan-Leray, e algumas aplicações na teoria de homologia.
In this work we present a study of the spectral sequence associated to the filltration (finite) of a chain complex of modules on an arbitrary ring R. In special, we emphasize the spectral sequences of Lyndon-Hochschild-Serre and Cartan-Leray and some applications in the homology theory.
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Gaboriau, Rénald. "Les ateliers Rob'Autisme : Le robot extension comme médiation thérapeutique auprès des personnes présentant un trouble du spectre autistique." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0016.
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L’utilisation des robots comme médiation thérapeutique pour les personnes présentant un Trouble du Spectre Autistique (TSA) est une pratique en plein essor. C’est en effet une méthode encourageante pour favoriser le développement de compétences sociales. De nombreuses expériences sont actuellement menées. Cependant, dans toutes les approches existantes, le paradigme du robot-compagnon est utilisé : le robot est programmé pour présenter des comportements pré-établis. Le projet Rob’Autisme propose une approche alternative : le robot est utilisé comme extension pour faire ou dire des choses. Les sujets présentant un TSA le programment et, par son truchement, agissent librement sur leur environnement social.De plus, ce projet inclut l’idée qu’ils pourront ensuite interagir avec les autres sans le robot. Cette thèse vise à comprendre l’intérêt de cette approche et évaluer les effets de la participation sur les interactions sociales. Durant deux ans, des groupes avec six adolescents ont été organisés et analysés à partir de méthodes quantitatives et qualitatives. Ces analyses montrent que cette approche favorise la tendance à aller vers les autres et interagir avec eux. Ce résultat est en outre généralisé à l’extérieurThe use of robots as a therapeutic mediator for peolple with Autism Spectrum Disorder (ASD) is a topic which tends to develop. Indeed, it is a promising method to promote the development of social skills. Many experiments are carried out currently. But in all existing approaches, the companion robot paradigm is used : the robot is programmed to present some pre-established behaviors. Rob’Autism Project propose an alternative approach : the robot is used as an extension for doing or talking things. The autistic subjects program it and therefore act on the social environment freely. This project includes ideas that they will be able to interact with the others without the robot. This thesis aims to understand the interest of this approach and asses the effects of participation on the social interactions. During two years, groups have been set up and analyzed with quantitative and qualitative methods. These analysis show that this approach favors the tendency to go towards the others and interact with them. This result is generalized outside the group
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Husk, Kerryn Michael. "Ethnic group affiliation and social exclusion in Cornwall : analysis, adjustment and extension of the 2001 England and Wales Census data." Thesis, University of Plymouth, 2012. http://hdl.handle.net/10026.1/906.
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This thesis provides a critical understanding of the size and relative position of the Cornish in Cornwall, a county in the south-west of the UK. Cornwall is a region which has experienced increased levels of disadvantage for a prolonged period of time. The indigenous people, whilst seeing a rise in their inclusion in ethnicity variables in the region, have remained under-researched in terms of their socio-economic position relative to the non-Cornish in the same geographic area. This thesis addresses this gap in the literature and represents the first in-depth examination of the group. The 2001 Census included an option to ‘write-in’ a Cornish ethnic identity, however whilst accurate in the responses it recorded the result was almost certainly an under-enumeration due to the lack of a dedicated tick-box selection. This thesis is a rigorous examination of the Cornish, starting with these data, estimating their size and socio-economic position (in terms of social exclusion) relative to non-Cornish individuals. Three stages of primary analysis sought to; analyse, adjust and extend the 2001 Census result to broadly estimate the size, links with exclusion and the causal processes behind these links. Firstly, an accurate picture of the size of the Cornish population was estimated using an innovative weighting strategy, developed to collate all other data referring to the Cornish and to derive weights for application to the raw Census data. Secondly, a stage of primary survey research examined this group more directly for links with social exclusion factors; and thirdly, a stage of qualitative interviews with knowledgeable individuals in the region lent depth to the findings and provided a more coherent explanatory framework. The results indicate that the Cornish are certainly more numerous than the 2001 Census had indicated. The proportion of individuals self-identifying as Cornish is likely to be closer to a quarter of the population rather than the 6.7% indicated in the 2001 ii data. There was some discrepancy in the data between the belief amongst the group of social exclusion and the reality. In order to explain the discrepancy, a model was used which explores the difference between personal-level experience and group level discrimination (Taylor et al 1990). The results of this thesis highlight the complex and multi-dimensional processes inherent in, firstly, the methodological and practical process of ethnicity measurement and, secondly, its use as an explanatory variable for social exclusion experience. Overall, this thesis represents the first and most comprehensive examination of the indigenous people of Cornwall and their relative lived experience compared to non-Cornish in the same area.
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Gomes, Neila Mara. "Sequências espectrais de Lyndon-Hochschild-Serre e de Cartan-Leray, e algumas aplicações /." São José do Rio Preto : [s.n.], 2009. http://hdl.handle.net/11449/94254.
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Orientador: Ermínia de Lourdes Campello FantiBanca: Luiz Queiroz Pegher
Banca: João Peres Vieira
Resumo: Neste trabalho apresentamos um estudo da sequência espectral associada à uma filtração (finita) de um complexo de cadeias de módulos sobre um anel arbitrário R. Em especial, destacamos as sequências espectrais de Lyndon-Hochschild-Serre e de Cartan-Leray, e algumas aplicações na teoria de homologia.
Abstract: In this work we present a study of the spectral sequence associated to the filltration (finite) of a chain complex of modules on an arbitrary ring R. In special, we emphasize the spectral sequences of Lyndon-Hochschild-Serre and Cartan-Leray and some applications in the homology theory.
Mestre
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Jaber, Mona. "Extension of the predictive GC-PPC-SAFT Equation of State to multifunctional molecules." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS476.
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Le but de cette thèse est de développer un modèle prédictif pour les calculs d'équilibres de phases en présence de molécules multifonctionnelles: c’est-à-dire des composés purs ramifiés avec plusieurs groupes polaires et des mélanges de ces composés avec l'eau et les alcanes. Deux défis sont identifiés:(1) Le branchement : un modèle GC-PPC-SAFT hétérosegmenté capable de prendre en compte la connectivité entre segments par rapport à l’homosegmenté disponible à ce jour a été codé dans le serveur IFPEN en collaboration avec l'Université de Stuttgart. Le paramétrage est ensuite basé sur une préalable analyse des données expérimentales afin de prédire correctement la pression de vapeur des alcanes linéaires, des alcanes ramifiés, des alcools linéaires et des diols. Une correction des paramètres en fonction de la distance entre différents groupes fonctionnels s’avère nécessaire. Aussi, une correction du terme chaîne dans l'approche hétérosegmentée afin de pouvoir réduire l'approche hétérosegmentée à l'approche homosegmentée pour des molécules de segments équivalents est proposée.(2) La multifonctionnalité: certains isomères contenant deux groupes associatifs se comportent différemment selon leur environnement. Ce phénomène est interprété en remarquant que la distance entre les groupes fonctionnels leur permet de se lier à l'hydrogène au sein de la molécule, désactivant ainsi l'association intermoléculaire. Les paramètres de certains groupes sont ensuite adaptés pour prendre en compte leur position dans la molécule. La correction permet d'étendre la prévisibilité du modèle à des mélanges eau + molécule fonctionnelle ramifiée ou alcane + molécules fonctionnelles ramifiéesThe purpose of this thesis is to develop a predictive model for phase equilibrium calculations of multifunctional molecules: branched pure compounds with several polar groups and mixtures of these compounds with water and alkanes. Two challenges have been identified:(1) Branching: a heterosegmented GC-PPC-SAFT model able to take into account the connectivity between segments as compared to the homosegmented GC-PPC-SAFT available so far has been coded in IFPEN server in collaboration with the University of Stuttgart. It is then parameterized using data analysis so as to fit the vapor pressure of linear alkanes, branched alkanes, linear alcohols and diols. A correction of some parameters that is function of the distance between functional groups was needed. Also, a correction of the chain term in the heterosegmented approach so as to be able to reduce the heterosegmented approach to the homosegmented one for molecules with equivalent segments is proposed. (2) Multifunctional molecules: some isomers containing two associating groups behave differently depending on their surroundings. This phenomenon is interpreted by noticing that the distance between functional groups makes it possible for them to hydrogen-bond within the molecule, thus deactivating the intermolecular association. The parameter of some functional groups is then adapted so as to take into consideration their position in the molecule. The correction makes it possible to extend the model predictability to mixtures of water + branched functional molecule or alkane + branched functional molecules
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Baynes, Samuel. "On generators, relations and D-simplicity of direct products, Byleen extensions, and other semigroup constructions." Thesis, University of St Andrews, 2015. http://hdl.handle.net/10023/7629.
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In this thesis we study two different topics, both in the context of semigroup constructions. The first is the investigation of an embedding problem, specifically the problem of whether it is possible to embed any given finitely presentable semigroup into a D-simple finitely presentable semigroup. We consider some well-known semigroup constructions, investigating their properties to determine whether they might prove useful for finding a solution to our problem. We carry out a more detailed study into a more complicated semigroup construction, the Byleen extension, which has been used to solve several other embedding problems. We prove several results regarding the structure of this extension, finding necessary and sufficient conditions for an extension to be D-simple and a very strong necessary condition for an extension to be finitely presentable. The second topic covered in this thesis is relative rank, specifically the sequence obtained by taking the rank of incremental direct powers of a given semigroup modulo the diagonal subsemigroup. We investigate the relative rank sequences of infinite Cartesian products of groups and of semigroups. We characterise all semigroups for which the relative rank sequence of an infinite Cartesian product is finite, and show that if the sequence is finite then it is bounded above by a logarithmic function. We will find sufficient conditions for the relative rank sequence of an infinite Cartesian product to be logarithmic, and sufficient conditions for it to be constant. Chapter 4 ends with the introduction of a new topic, relative presentability, which follows naturally from the topic of relative rank.
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Ross, Ruth O., and n/a. ""The extension group" - a part-time, withdrawal, enrichment program for gifted and talented children at Holt Primary School, A.C.T. : an action research study." University of Canberra. Education, 1985. http://erl.canberra.edu.au./public/adt-AUC20061107.160754.
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Over the past six years, a part-time withdrawal-from-mainstream-class enrichment program for gifted and talented
children has been operating at the Holt Primary School in the
Australian Capital Territory.
In keeping with the neighbourhood school policy of the ACT
Schools Authority, the program caters only for children within
the school and has included those from grades three to six.
Based on Renzulli's Enrichment Triad Model, the program has
a thematic approach which provides opportunities for participants
to pursue both group and individual research on topics of
interest to them.
Identified children remain in the program for as long as
possible and some have continued for as long as three years when
resources have been available.
This Action Research Study by the Co-ordinator of the
program describes the setting up, objectives, identification
methods, resources and evaluation.
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Docherty, Pamela Jane. "Central extensions of Current Groups and the Jacobi Group." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7838.
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A current group GX is an infinite-dimensional Lie group of smooth maps from a smooth manifold X to a finite-dimensional Lie group G, endowed with pointwise multiplication. This thesis concerns current groups G§ for compact Riemann surfaces §. We extend some results in the literature to discuss the topology of G§ where G has non-trivial fundamental group, and use these results to discuss the theory of central extensions of G§. The second object of interest in the thesis is the Jacobi group, which we think of as being associated to a compact Riemann surface of genus one. A connection is made between the Jacobi group and a certain central extension of G§. Finally, we define a generalisation of the Jacobi group that may be thought of as being associated to a compact Riemann surface of genus g ≥ 1.
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Tongchai, Nilubon. "Enhancing learning through opening the group model in a synchronous computer-based environment." Thesis, Connect to e-thesis, 2008. http://theses.gla.ac.uk/195/.
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Thesis (Ph.D.) - University of Glasgow, 2008.Ph.D. thesis submitted to the Faculty of Education, Centre for the Support for Learning, University of Glasgow, 2008. Includes bibliographical references. Print version also available.
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Darr, Dietrich. "Effective even when neglected: Farmer groups and the diffusion of agroforestry innovations in rural communities of Eastern Africa." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1227250287917-45148.
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The purpose of the current dissertation is to explore the contribution of development-oriented farmer groups to the diffusion of innovations in rural communities of Kenya and Ethiopia, to identify the key factors that determine the effectiveness of diffusion, and to derive recommendations that aim at better utilizing the potential of groups for rural extension work. A profound review of four theoretical frameworks served to derive a multiple-pathway model of innovation diffusion that amalgamates major concepts of the social network and functional group theory. By accommodating multiplex social relationships and by facilitating analyses at multiple levels the model alleviates major conceptual shortcomings of previous research. The research employs a multiple case study design. Four peasant communities have been investigated that are largely comparable in respect with bio-physical conditions. The case studies aim to cover the maximum diversity with regard to the role of farmer groups in the prevailing extension approach, as well as the mode of group organization. Data collection tools comprise reconnaissance surveys, standardized household interviews (N=841), qualitative key informant and in-depth interviews, participant observation, and the review of secondary sources. Group and non-group social networks constitute the units of analysis. Inferential statistical analyses mainly used multivariate linear regression techniques. The findings illustrate that farmers, through their group and non-group networks and under group-oriented and individual extension alike, exchange information, knowledge, social pressures and other forms of influence that shape their individual adoption decisions. Yet, innovations tend to disseminate more effectively in farmer groups vis-à-vis non-group networks, and the groups tend to be more effective when addressed by extension agents. Lack of access to extension services represents a crucial limitation to innovation adoption in the study villages. Yet, increased extension intensity has proved to foster innovation diffusion only in situations of group extension, whereas intensified individual extension services do not considerably increase horizontal farmer-to-farmer knowledge exchange. The research reveals that the advantage of farmer groups can be attributed to their dimorphic character combining the bridging and bonding effects of ‘weak’ and ‘strong’ ties. By facilitating the emergence of cohesive relationships among the group members and by simultaneously enhancing the members’ exposure to external information sources group-oriented extension work considerably contributes to foster the diffusion of innovations among farmers. Intermediate absolute levels of group homogeneity best facilitate the diffusion of innovations among the group members. The findings suggest that increased group activity can overcome diffusion barriers that arise from too heterogeneous or too homogeneous configurations alike. Member commitment is the group climate dimension most consistently related to diffusion effectiveness in farmer groups. The results suggest that group-oriented extension services can alleviate obstructions of the diffusion process that result from less favorable group climate. Thus, this research work proposes that the effectiveness of innovation diffusion among farmers is under the managerial control of the extension agencies in group-oriented extension approaches through at least one of the following mechanisms: (a) promoting the emergence of cohesive member relationships, which in turn foster effective innovation spread; (b) stimulating the activity of farmer groups, which in turn compensates for less effective diffusion under unfavorable group composition; and (c) compensating for diffusion barriers that result from a less favorable group climate. Recommendations refer to the improvement of extension practice and directions for future research.
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Oliveira, Everton Luiz de [UNESP]. "Construções de reticulados via extensões cíclicas de grau ímpar." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/86491.
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Made available in DSpace on 2014-06-11T19:22:18Z (GMT). No. of bitstreams: 0
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oliveira_el_me_sjrp.pdf: 531004 bytes, checksum: 26290057a6f49446476e6e8192925843 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Neste trabalho, descrevemos cíclicas de reticulados algébricos Zn-rotacionados de dimensão ímpar. Essas construções são obtidas através da imersão Rn, via homomorfismo canônico, de determinados Z-módulos livres de posto finito contidos em subcorpos de extensões ciclotômicas do tipo Q(ζp), Q(ζp2), Q(ζpq)e Q(ζpq2), com p e q primos ímpares. Caracterizamos os reticulados e apresentamos propriedades e aplicações na Teoria da Informação.
In this work we describe cyclic constructions of odd dimension. These constructions are obtained by immersion in Rn via the canonical homomorphism, of certain Z-free modules of finite rank contained in subfield cyclotomic extensions of type Q(ζp), Q(ζp2), Q(ζpq)e Q(ζpq2), com p e q odd prime. Featuring the obtained lattices and presenting properties and applications in Information Theory.
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King, Christine Anne. "Systemic processes for facilitating social learning : challenging the legacy /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5776-9.pdf.
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McHardy, Robert David. "Building a mutually-desirable relationship between a higher education institution's academic schools and its adult/continuing education unit : a case study analysis of Abu Dhabi University and its knowledge group (Abu Dhabi, United Arab Emirates)." Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.563994.
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Historically, many higher education institutions have been structurally and culturally compartmentalised and subunits such as continuing education have been marginalised, merged or divested. In response to a variety of external phenomena, some higher education institutions are re-examining their internal and external relationships, including the relationship between their academic and continuing education units. This research examines the efforts of a higher education institution in the United Arab Emirates to improve its overall effectiveness by changing the nature of the relationship between its academic and continuing education units. A review of theory- and practice-based higher education, organisational culture and inter-/intra-organisational relationship literature revealed significant support for each partner's goals for the new relationship and was used to provide the parties with a series of recommendations for successful formulation, actualisation and governance. These results add to the literature and practice of higher education and continuing higher education, particularly in the area of relationship-building among organisational subunits and subcultures.
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Xu, Binbin. "L'identité de Pleijel hyperbolique, la métrique de pression et l'extension centrale du groupe modulaire via quantification de Chekhov-Fock." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENM068/document.
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Cette thèse consiste en trois parties que j'ai faites pendant ces trois ans.La première partie va être constituée de l'étude de la distribution de la longueur de corde sur le plan hyperbolique. Nous montrons l'identité de Pleijel pour le plan hyperbolique. En utilisant cette identité, nous remontrons l'identité de formule de Crofton et l'inégalité isopérimétrique pour le plan hyperbolique, et puis nous calculons la distribution de la longueur de corde associée à un triangle idéal et celle associée à un quadrilatère idéal. Ensuit, nous montons les résultats analogues pour les surfaces riemannienne simplement connexes avec la courbure constante. La seconde partie va contribuer aux études de la métrique de pression sur l'espace de Teichmüller d'un tore privé d'un disque. En étudiant la dégénération du tore quand la longueur du bord va à l'infini, nous trouvons la relation de cette métrique avec la métrique de pression sur l'espace modulaires des graphes métriques. Nous montrons ensuite que la fonction de l'entropie n'est pas constante sur les feuilles symplectique de l'espace Teichmüller d'une surface à bord.Finalement, la troisième partie concerne la quantification de l'espace de Teichmüller d'une surface avec les piqûres. nous montrons. Dans ce chapitre, nous étudions l'extension centrale du groupe modulaire via la quantification de Chekhov-Fock et calculons sa classe de cohomologie qui est 12 fois la classe de Meyer plus les classes d'Euler associées aux piqûresThis thesis consists of three parts corresponding to the three subjects that I have studied during the last three years.The first part contains the study of the chord length distribution associated to a compact (or non-compact) domain in the hyperbolic plane. We prove the hyperbolic Pleijel identity. By using this identity, we find new approaches to the Crofton's formula and the isoperimetric inequality, and then compute the chord length distribution associated to an ideal triangle and that associated to an ideal quadrilateral. Then we prove the analogue results for the simply connected Riemannian surface with constant curvature.The second part of this thesis (Chapter 5) consists of the study of the pressuremetric on the Teichmüller space of one-holed torus. By studying the degeneration of the torus when the boundary length goes to infinity, we find the relation of this metric to the pressure metric on the moduli space of metric graphs. Then we study the entropy function and prove that it is not constant on the symplectic leaf of the Teichmüller space of a bordered surface.Finally, the third part concerns the quantization of the Teichmüller space of a punctured surface. In this chapter, we study the central extension of the mapping class group coming from the quantization and compute its cohomology class which is 12 times the Meyer class plus the Euler classes associated to punctures
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Hauseux, Julien. "Extensions entre séries principales p-adiques et modulo p d'un groupe réductif p-adique déployé." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112411/document.
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Cette thèse est une contribution à l'étude des représentations p-adiques (c'est-à-dire continues unitaires sur des espaces de Banach p-adiques) et modulo p (c'est-à-dire lisses sur un corps fini de caractéristique p) d'un groupe réductif p-adique déployé G.Nous déterminons les extensions entre séries principales p-adiques et modulo p de G Pour cela, nous calculons le delta-foncteur H•OrdB des parties ordinaires dérivées d'Emerton relatif à un sous-groupe de Borel sur une série principale en utilisant une filtration de Bruhat.Nous déterminons également les extensions d'une série principale par une représentation ordinaire (c'est-à-dire obtenue par induction parabolique à partir d'une représentation spéciale du Levi tordue par un caractère), ainsi que les extensions de Yoneda de longueur supérieure entre séries principales modulo p sous une conjecture d'Emerton vraie pour GL2.Nous montrons de plus qu'il n'existe pas de « chaîne » de trois séries principales p-adiques ou modulo p distinctes de G. Pour cela, nous calculons partiellement le delta-foncteur H•OrdP relatif à un sous-groupe parabolique quelconque sur une série principale. En exploitant ce résultat, nous prouvons une conjecture de Breuil et Herzig sur l'unicité de certaines représentations p-adiques de G dont les constituants sont des séries principales, ainsi que son analogue modulo p.Enfin, nous énonçons une nouvelle conjecture sur les extensions entre représentations modulo p irréductibles de G obtenues par induction parabolique à partir d'une représentations supersingulière du Levi. Nous prouvons cette conjecture pour les extensions par une série principaleThis thesis is a contribution to the study of p-adic (i.e. unitary continuous on p-adic Banach spaces) and mod p (i.e. smooth over a finite field of characteristic p) representations of a split p-adic reductive group G.We determine the extensions between p-adic and mod p principal series of G. In order to do so, we compute Emerton's delta-functor H•OrdB of derived ordinary parts with respect to a Borel subgroup on a principal series using a Bruhat filtration.We also determine the extensions of a principal series by an ordinary representation (i.e. parabolically induced from a special representation of the Levi twisted by a character), as well as the Yoneda extensions of higher length between mod p principal series under a conjecture of Emerton true for GL2.Moreover, we show that there exists no “chain” of three distinct p-adic or mod p principal series of G. In order to do so, we partially compute the delta-functor H•OrdP with respect to any parabolic subgroup on a principal series. Exploiting this result, we prove a conjecture of Breuil and Herzig on the uniqueness of certain p-adic representations of G whose constituents are principal series, as well as its mod p analogue.Finally, we formulate a new conjecture on the extensions between irreducible mod p representations of G parabolically induced from a supersingular representation of the Levi. We prove this conjecture for extensions by a principal series
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Archer, Claude. "Classification of group extensions." Doctoral thesis, Universite Libre de Bruxelles, 2002. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211419.
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Mkiva, Soga Loyiso Tiyo. "The non-cancellation groups of certain groups which are split extensions of a finite abelian group by a finite rank free abelian group." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8520_1262644840.
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The groups we consider in this study belong to the class X0 of all finitely generated groups with finite commutator subgroups.
34
Kremer, Stefan [Verfasser], P. [Akademischer Betreuer] Wölfle, and R. [Akademischer Betreuer] Frésard. "Thermal and Electric Properties of the Delafossites : The Apparent Fermi Liquid Scenario and the Extension of the Density Matrix Renormalization Group Method to Finite Temperatures / Stefan Kremer. Betreuer: P. Wölfle ; R. Frésard." Karlsruhe : KIT-Bibliothek, 2011. http://d-nb.info/101481779X/34.
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Oliveira, Everton Luiz de. "Construções de reticulados via extensões cíclicas de grau ímpar /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/86491.
Full textAbstract:
Orientador: Antonio Aparecido de AndradeBanca: Edson Donizete de Carvalho
Banca: Clotilzio Moreira dos Santos
Resumo: Neste trabalho, descrevemos cíclicas de reticulados algébricos Zn-rotacionados de dimensão ímpar. Essas construções são obtidas através da imersão Rn, via homomorfismo canônico, de determinados Z-módulos livres de posto finito contidos em subcorpos de extensões ciclotômicas do tipo Q(ζp), Q(ζp2), Q(ζpq)e Q(ζpq2), com p e q primos ímpares. Caracterizamos os reticulados e apresentamos propriedades e aplicações na Teoria da Informação.
Abstract: In this work we describe cyclic constructions of odd dimension. These constructions are obtained by immersion in Rn via the canonical homomorphism, of certain Z-free modules of finite rank contained in subfield cyclotomic extensions of type Q(ζp), Q(ζp2), Q(ζpq)e Q(ζpq2), com p e q odd prime. Featuring the obtained lattices and presenting properties and applications in Information Theory.
Mestre
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Haubold, Niko. "Compressed Decision Problems in Groups." Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-85413.
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Wir beschäftigen uns mit Problemen der algorithmischen Gruppentheorie und untersuchen dabei die Komplexität von komprimierten Versionen des Wortproblems und des Konjugationsproblems für endlich erzeugte Gruppen.
Das Wortproblem fragt für eine feste, endlich erzeugte Gruppe ob ein gegebenes Wort über der Erzeugermenge das neutrale Element der Gruppe repräsentiert. Wir betrachten das gegebene Wort jedoch in einer komprimierten Form, als Straight-line Program (SLP) und untersuchen die Komplexität dieses Problems, das wir \'komprimiertes Wortproblem\' nennen. SLPs sind kontextfreie Grammatiken, die genau einen String erzeugen. Die Eingabegröße ist dabei stets die Größe des gegebenen SLPs. Eine Hauptmotivation ist dabei, dass für eine feste endlich erzeugte Gruppe das Wortproblem ihrer Automorphismengruppe durch eine Turingmaschine in Polynomialzeit auf das komprimierte Wortproblem der Gruppe selbst reduzierbar ist.
Wir untersuchen das komprimierte Wortproblem für die verbreiteten Gruppenerweiterungen HNN-Erweiterungen (amalgamierte Produkte und Graphprodukte) und können zeigen, dass sich Instanzen des komprimierten Wortproblems von einer Turingmaschine in Polynomialzeit auf Instanzen des komprimierten Wortproblems der Basisgruppe (respektive Basisgruppen und Knotengruppen) reduzieren lassen. Weiterhin zeigen wir, dass das komprimierte Wortproblem für endlich erzeugte nilpotente Gruppen von einer Turingmaschine in Polynomialzeit entscheidbar ist.
Wir betrachten außerdem eine komprimierte Variante des Konjugationsproblems. Das unkomprimierte Konjugationsproblem fragt für zwei gegebene Wörter über den Erzeugern einer festen endlich erzeugten Gruppe, ob sie in dieser Gruppe konjugiert sind. Beim komprimierten Konjugationsproblem besteht die Eingabe aus zwei SLPs und es wird gefragt, ob die beiden Wörter die von den SLPs erzeugt werden in der Gruppe konjugierte Elemente präsentieren. Wir konnten zeigen, dass sich das komprimierte Konjugationsproblem für Graphgruppen in Polynomialzeit entscheiden lässt.
Weiterhin haben wir das Wortproblem der äußeren Automorphismengruppen von Graphprodukten endlich erzeugter Gruppen untersucht. Durch den engen Zusammenhang des komprimierten Konjugationsproblems einer Gruppe mit dem Wortproblem der äußeren Automorphismengruppe konnten wir zeigen, dass sich das Wortproblem der äußeren Automorphismengruppe eines Graphprodukts von endlich erzeugten Gruppen durch eine Turingmaschine in Polynomialzeit auf Instanzen von simultanen komprimierten Konjugationsproblemen der Knotengruppen und Instanzen von komprimierten Wortproblemen der Knotengruppen reduzieren lässt.
Als Anwendung gelten obige Resultate auch für right-angled Coxetergruppen und Graphgruppen, da beide spezielle Graphprodukte sind. So folgt beispielsweise, dass das komprimierte Wortproblem einer right-angled Coxetergruppe in Polynomialzeit entscheidbar ist.
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Zainuddin, Hishamuddin. "Group-theoretic quantisation and central extensions." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6053/.
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This work is concerned with the applications of Isham's group-theoretic quantisation programme to simple systems which involve central extensions of some symmetry group. Of particular interest are those systems with a 'Wess-Zumino'-like term in their actions where other nontrivial modifications are necessary. In Chapters 1 and 2, a review of the necessary tools used in this work as well as outlines of the group-theoretic quantisation programme are given to facilitate a smooth discussion in the latter chapters. The programme is first exemplified by the normal quantum mechanics on R". This example also involves central extensions but of a slightly different nature from those which arise from systems with a 'Wess-Zumino'-like term. Chapter 3 forms the core of the whole work. The discussions there provide the basis for further examples. It is concerned with the group-theoretic quantisation of the system of a particle moving on the two-torus in a constant magnetic field with quantised flux. The case without the magnetic field is also given for comparison. The canonical group for the case with the magnetic field is required to be the central extension of the universal cover of the canonical group for the case without the magnetic field. These results are then generalised to the corresponding systems on the n-torus. Chapter 4 is a digression from the main topic of quantisation and central extensions to the discussions of a-models with Wess-Zumino term. The main purpose of this chapter is to provide a parallel between these σ-models and the systems of a particle moving in a magnetic field (as in Chapter 3). The general construction of a Wess-Zumino term is given along with the discussion of an Abelian gauge symmetry that the term provides for the σ-models. The a-models can be interpreted as systems of a 'particle' moving on an infinite-dimensional configuration space in a background 'functional magnetic field'. This interpretation is further reinforced by the discussions of Noether's theorem and topological effects.
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Hekmati, Pedram. "Group Extensions, Gerbes and Twisted K-theory." Licentiate thesis, Stockholm : Teoretisk fysik, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4654.
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Green, Shawn Jeffrey. "Extensions of the Power Group Enumeration Theorem." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7526.
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The goal of this paper is to develop extensions of Polya enumeration methods which count orbits of functions. De Bruijn, Harary, and Palmer all worked on this problem and created generalizations which involve permuting the codomain and domain of functions simultaneously. We cover their results and specifically extend them to the case where the group of permutations need not be a direct product of groups. In this situation, we develop a way of breaking the orbits into subclasses based on a characteristic of the functions involved. Additionally, we develop a formula for the number of orbits made up of bijective functions. As a final extension, we also expand the set we are acting on to be the set of all relations between finite sets. Then we show how to count the orbits of relations.
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Martin, Cody Michael. "Knot Groups and Bi-Orderable HNN Extensions of Free Groups." Diss., North Dakota State University, 2020. https://hdl.handle.net/10365/31814.
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Suppose K is a fibered knot with bi-orderable knot group. We perform a topological winding operation to half-twist bands in a free incompressible Seifert surface Σ of K. This results in a Seifert surface Σ' with boundary that is a non-fibered knot K'. We call K a fibered base of K'. A fibered base exists for a large class of non-fibered knots.
We prove K' has a bi-orderable knot group if Σ' is obtained from applying the winding operation to only one half-twist band of Σ. Utilizing a Seifert surface gluing technique, we obtain HNN extension group presentations for both knot groups that differ by only one relation. To show the knot group of K' is bi-orderable, we apply the following:
Let G be a bi-ordered free group with order preserving automorphism ɑ. It is well known that the semidirect product ℤ ×ɑG is a bi-orderable group. If X is a basis of G, a presentation of ℤ ×ɑG is ⟨ t,X | R ⟩, where the relations are R = {txt-1}ɑ(x)-1 : x ∈ X}. If R' is any subset of R, we prove that the group H =⟨ t,X | R' ⟩ is bi-orderable. H is a special case of an HNN extension of G. Finally, we add new relations to the group presentation of H such that bi-orderability is preserved.
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Ruzziconi, Romain. "On the Various Extensions of the BMS Group." Doctoral thesis, Universite Libre de Bruxelles, 2020. https://dipot.ulb.ac.be/dspace/bitstream/2013/307600/4/Contents.pdf.
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The Bondi-Metzner-Sachs-van der Burg (BMS) group is the asymptotic symmetry group of radiating asymptotically flat spacetimes. It has recently received renewed interest in the context of the flat holography and the infrared structure of gravity. In this thesis, we investigate the consequences of considering extensions of the BMS group in four dimensions with superrotations. In particular, we apply the covariant phase space methods on a class of first order gauge theories that includes the Cartan formulation of general relativity and specify this analysis to gravity in asymptotically flat spacetime. Furthermore, we renormalize the symplectic structure at null infinity to obtain the generalized BMS charge algebra associated with smooth superrotations. We then study the vacuum structure of the gravitational field, which allows us to relate the so-called superboost transformations to the velocity kick/refraction memory effect. Afterward, we propose a new set of boundary conditions in asymptotically locally (A)dS spacetime that leads to a version of the BMS group in the presence of a non-vanishing cosmological constant, called the Λ-BMS asymptotic symmetry group. Using the holographic renormalization procedure and a diffeomorphism between Bondi and Fefferman-Graham gauges, we construct the phase space of Λ-BMS and show that it reduces to the one of the generalized BMS group in the flat limit.Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Gandolfi, Guillaume. "Résultats sur les extensions singulières des groupes d'Artin et de tresses virtuelles." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMC215.
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Cette thèse se propose d’étudier deux objets liés aux monoïdes de tresses singulières, le morphisme de désingularisation et la famille des invariants de Vassiliev, transposés dans les cadres respectifs des monoïdes d’Artin singuliers et des monoïdes de tresses virtuelles singulières. Dans le premier chapitre, on rappelle les définitions de ces deux objets dans leur contexte d'origine, celui des monoïdes de tresses singulières qui sont des extensions des groupes de tresses, puis celles des principales problématiques s'y rapportant, qui sont la déterminations de l'injectivité du morphisme de désingularisation et de la séparabilité des tresses (classiques ou singulières) par les invariants de Vassiliev, ainsi que les résultats qui répondent à ces problématiques. Dans le second chapitre, on redonne les fondamentaux de la théorie des groupes d'Artin et les définitions des principales familles de groupes d'Artin avant de rappeler la définition d'extension singulière associée à un groupe d'Artin. On démontre alors l'analogue singulier du résultat de Van der Lek sur les sous-groupes paraboliques d'un groupe d'Artin pour les monoïdes singuliers d'Artin de type FC et de type affine. On rappelle qu'il est également possible dans ce nouveau contexte de définir un morphisme de désingularisation, des invariants de Vassiliev ainsi que de reformuler les mêmes problématiques que dans le cades des tresses, et après avoir redonné les résultats connus sur ces problématiques pour les groupes d'Artin angle droit et les groupes d'Artin de type I, on démontre l'injectivité du morphisme de désingularisation pour les groupes d'Artin de type A affine ainsi que la séparabilité des éléments des groupes de type A affine et de type B par leurs invariants de Vassiliev respectifs. Dans les troisième et quatrièmes chapitres, on rappelle les définitions des groupes de tresses virtuelles, qui sont d'autres extensions des groupes de tresses, et des monoïdes de tresses virtuelles singulières qui leur sont associés. On démontre que les monoïdes de tresses virtuelles singulières sont bien des extensions communes aux groupes de tresses virtuelles et aux monoïdes de tresses singulières. On étend ensuite aux tresses virtuelles singulières les interprétations combinatoires (en termes de diagrammes de Gauss) et topologiques (en termes de classes stables de tresses abstraites) déjà connues pour les tresses virtuelles. Enfin, après avoir redéfini le morphisme de désingularisation et les invariants de Vassiliev pour les tresses virtuelles, on montre que la résolution des problématiques qui y sont liées est équivalente à la résolution de ces mêmes problématiques pour une famille de groupes d'Artin particuliers qui sont des sous-groupes des groupes de tresses virtuelles. On conclut la thèse par une étude sur le problème de la plongeabilité d'un monoïde dans sa monoïde dans son groupe enveloppant sur laquelle on s'appuie pour démontrer certains résultats de la thèseThis thesis offers to study two objects related to singular braid monoids, the desingularization map and the family of Vassiliev invariants, in the respective framework of the singular Artin monoids and the singular virtual braid monoids. In the first chapter, we recall the definitions of these two objects in their original setting, namely the setting of the singular braid monoids which are extensions of the braid groups, before stating the problems which are related to these objects, i.e. deciding whether the desingularization map is one-to-one and whether the Vassilev invariants separate the (classical or singular) braids, as well as the results that answer them. In the second chapter, we give the basics of the theory of Artin groups and the definition of the main families of Artin groups before recalling the definition of the singular extension of an Artin group. We prove a singular version of Van der Lek's theorem on parabolic subgroups of an Artin group for singular Artin monoids of FC type and of affine type. We recall that it is still possible to define in this new framework a desingularization map, Vassiliev invariants and to state the same problems as in the framework of braids, and after giving the results already known about these problems for right angle Artin groups and Artin groups of type I, we prove that the desingularization maps for Artin groups of type A affine are one-to-one and that the Vassiliev invariants respectively of Artin groups of type A affine and of type B separate the elements of these groups. In the third and furth chapter, we recall the definitions of the virtual braid groups, which are other extensions of braid groups, and the singular virtual braid monoids related to them. We show that the singular virtual braid monoids are indeed common extensions of the virtual braid groups and of the singular braid monoids. We then extend to singular virtual braids the combinatorial and topological interpretation (respectively in terms of Gauss diagrams and in terms of stable classes of abstract braids) which was already known for virtual braids. Finally, after defining the desingularization map and the Vassilev invariants for virtual braids, we show that the resolution of the problems related to these objects is equivalent to the resolution of the same problems for a family of Artin groups which appears to be subgroups of the virtual braid groups. We end the thesis with a study on the embeddability of a monoid in its enveloping group, on which several results of the thesis are based on
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Lindell, Jonatan. "Profinite Groups and Infinite Galois Extensions." Thesis, Uppsala universitet, Algebra och geometri, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-398139.
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Blue, Meredith Patricia. "Generic Galois extensions for groups or order p³ /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Jabardo, Cristina Saiz. "Extensão da cláusula compromissória na arbitragem comercial internacional: o caso dos grupos societários." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/2/2135/tde-06102010-130941/.
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O objeto de estudo desta dissertação é a abrangência subjetiva da cláusula compromissória, especificamente daquela celebrada por sociedades pertencentes a grupos societários. O problema, ainda novo no Brasil devido ao desenvolvimento recente da arbitragem em nosso país, já foi objeto de muito debate na Europa e nos Estados Unidos, onde a arbitragem é usada há muitos anos como método alternativo de resolução de conflitos. No âmbito da arbitragem comercial internacional, consolidou-se, tanto na jurisprudência como na doutrina, a teoria da unidade econômica dos grupos societários. Ela reconhece a especificidade do problema que a presença de agrupamentos de sociedades suscita na arbitragem, devido, essencialmente, à dupla realidade que eles representam unidade diretiva e econômica e diversidade jurídica. Nesta dissertação, procuramos expor as bases sobre as quais essa teoria, consolidada na prática comercial internacional, se assenta. Se no Brasil o tema não foi suficientemente discutido, podemos aprender as lições daqueles que não só já debateram exaustivamente a questão como, também, parecem já ter encontrado uma solução, ainda que ela não seja indene de críticas e ainda mereça ser aperfeiçoada. De início, tentamos conceituar e caracterizar os grupos societários. Em seguida, fizemos um apanhado de casos emblemáticos da jurisprudência arbitral e estatal, de diversos países, que recorreram à teoria da unidade econômica do grupo. Nosso intuito foi verificar a solução conferida ao problema por aqueles que se depararam com ele no caso concreto. Depois, procuramos expor a visão da doutrina sobre a teoria da unidade econômica do grupo, para podermos concluir onde reside o problema central da questão. Ao fim, discutimos o possível obstáculo, apontado por alguns autores, à aplicação da teoria no Direito brasileiro.The purpose of this paper is to discuss who are the parties to the arbitration agreement, especially regarding the convention executed by companies that form part of a group. The issue, still topical in Brazil due to the recent development of the arbitration in our country, has already been subject to much debate in Europe and in the United States, where arbitration has been used for years as an alternative dispute resolution method. In international arbitration, the group of companies theory has been restated, both within the legal authorities and in case law. Such theory acknowledges the specificity of the issue raised by the presence of groups of companies in arbitration, especially due to their dual characteristics managerial and economical unit and legal diversity. In this paper, we have sought to settle the basis over which such theory, already settled in the international commercial arbitration practice, is construed. Since in Brazil the subject hás been scarcely discussed, we may learn lessons from those who have not only exhaustively debated it but who also seem to have found a way to solve it, even if it is not immune to criticism and still ought to be improved. We have initially tried to clarify the notion and the characteristics of the groups of companies. We have subsequently gathered a number of illustrative arbitral and state case law, from different countries, which have made use of the group of companies theory. Our aim was to verify the solution given to the issue by those who have actually been faced with the problem. Then, we have tried to present the legal authoritys view on the group of companies theory in order to conclude where the issue is in fact centered. In the end, we have discussed a possible obstacle, which certain authors have raised, as to the application of the theory in the Brazilian Law.
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Zerbes, Sarah. "Selmer groups over p-adic Lie extensions." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613792.
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Barrera, Mora Jose Felix Fernando. "On radical extensions and radical towers." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184833.
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Let K/F be a separable extension. (i) If K = F(α) with αⁿ ∈ F for some n, K/F is said to be a radical extension. (ii) If there exists a sequence of fields F = F₀ ⊆ F₁ ⊆ ... ⊆ F(s) = K so that Fᵢ₊₁ = Fᵢ(αᵢ) with αᵢⁿ⁽ⁱ⁾ ∈ Fᵢ for some nᵢ ∈ N, charF ∧nᵢ for every i, and [Fᵢ₊₁ : Fᵢ] = nᵢ, K/F is said to be a radical tower. In the first part of this work, we present two theorems which give sufficient conditions for a field extension K/F to be radical. In the second part, we present results which provide conditions under which every subfield of a radical tower is also a radical tower.
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Blondeau, Julien. "Déformation des extensions peu ramifiées en P." Phd thesis, Université de Franche-Comté, 2011. http://tel.archives-ouvertes.fr/tel-00936135.
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Santos, Pereira Tiago Tavares. "Changing places? : the extension of research groups through European research collaborations." Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324155.
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Touzé, Antoine. "Cohomologie rationnelle du groupe linéaire et extensions de bifoncteurs." Phd thesis, Université de Nantes, 2008. http://tel.archives-ouvertes.fr/tel-00289942.
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Le but de cette thèse est d'obtenir des résultats sur la cohomologie rationnelle du groupe linéaire. Nous attaquons ce problème en le transposant dans la catégorie des bifoncteurs polynomiaux, dans laquelle les calculs sont plus aisés. Nous rappelons dans un premier temps la structure de la catégorie des bifoncteurs polynomiaux sur un anneau commutatif quelconque. Nous démontrons que la cohomologie des bifoncteurs calcule la cohomologie rationnelle du groupe linéaire sur un anneau quelconque (ce résultat n'était auparavant connu que sur un corps). Puis nous développons des techniques générales pour le calcul de la cohomologie des bifoncteurs. Nous introduisons notamment de nouveaux outils efficaces pour étudier la torsion de Frobenius en caractéristique p. Enfin, nous appliquons ces méthodes à des familles explicites de bifoncteurs. Nous obtenons ainsi de nouveaux résultats (par exemple des séries de Poincaré) sur la cohomologie rationnelle à valeur dans des représentations classiques, telles que les puissances symétriques et divisées des twists de l'algèbre de Lie du groupe linéaire.