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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Desafios no fortalecimento do processo da auto-organização comunitária na perspectiva da economia solidária: o caso da comunidade Quilombola da Tapera Melão

Santos, Andréa Marques 30 May 2014 (has links)
Submitted by Tatiana Lima (tatianasl@ufba.br) on 2015-03-19T18:41:46Z No. of bitstreams: 1 PDF.pdf: 3062228 bytes, checksum: 30095e62ba6a03f41c0212ea514923cf (MD5) / Approved for entry into archive by Tatiana Lima (tatianasl@ufba.br) on 2015-03-20T19:20:37Z (GMT) No. of bitstreams: 1 PDF.pdf: 3062228 bytes, checksum: 30095e62ba6a03f41c0212ea514923cf (MD5) / Made available in DSpace on 2015-03-20T19:20:37Z (GMT). No. of bitstreams: 1 PDF.pdf: 3062228 bytes, checksum: 30095e62ba6a03f41c0212ea514923cf (MD5) / Este trabalho apresenta resultados de uma pesquisa que teve como objetivo identifi-car os desafios enfrentados pelos quilombolas da comunidade da Tapera Melão, em Irará-BA no processo de fortalecimento de sua auto-organização comunitária. A pes-quisa foi desenvolvida em 2013 e 2014 e envolveu moradores da comunidade . Ini-cialmente foi realizada uma pesquisa bibliográfica com o objetivo de conhecer a his-tória do município de Irará e da comunidade Tapera Melão, para a partir daí proce-dermos uma investigação in loco sobre os aspectos físico, econômico, cultural e so-cial desta comunidade. Essa investigação ocorreu através de observações diretas, realização de entrevista semiestruturada e registro fotográfico. Este material serviu como suporte para a reflexão sobre elementos/ aspectos da comunidade fundamen-tais para a trajetória da mesma. Como resultados da investigação destacamos a atuação do grupo de Economia Solidária Beijuzeiras da Tapera que demonstra um crescente processo de auto-organização comunitária e uma sociabilidade que con-verge para a construção de Redes de Economia Solidária. São apresentados tam-bém alguns dos desafios que a comunidade enfrenta para o seu processo de forta-lecimento, como o acesso ás incubadoras universitárias, o desafio da articulação para a construção de Rede local de E.S e por fim, a necessidade de maior articula-ção com organizações sociais e de fomento. This paper presents results of a survey that aimed to identify the challenges faced by the Maroons Tapera Melão community in Irará - BA in the process of strengthening its community self-organization . The research was conducted in 2013 and 2014 and involved community residents Tapera Melão . Initially a search in order to know the history of the municipality of Irará and the community of Tapera Melão, from there an investigation about the physical, economic, cultural and social aspects of the community was held. This research occurred through direct observation, conducting semi-structured interviews and photographic record. This material served as support for reflection on elements / fundamental aspects for the community's history. As a result of the investigation, we can highlight the actions of the group of Economia Sol-ídária Beijuzeira da Tapera (Solidarity Economy Beijuzeiras of Tapera), that is demonstrating an increasing process of self-organization within the community and sociability, which converges to one possible construction of the Solidarity Economy Network. It is also presented few of the challenges that the community is presenting for its process of strengthening, as access to university incubators, the challenge of integration for building local networks of E.S and finally, the need for greater coordi-nation with social organizations and funding.
22

Auto-organização interfacial durante a eletrodeposição de ligas Cu-Sn em regime oscilatório / Interfacial self-organization during electrodeposition of Cu-Sn alloys under oscillatory condition

Edson Joanni 10 January 2007 (has links)
A emergência de estruturas espaço-temporais auto-organizadas em sistemas químicos abertos e afastados do estado de equilíbrio termodinâmico resulta da cooperação entre os processos de reação e transporte de espécies ativas e tem se tornado uma área de intensa atividade nos últimos anos. Auto-organização dinâmica na interface sólido/líquido durante a eletrodeposição de Cu-Sn em regime oscilatório é o tema central do presente trabalho. O sistema estudado consistiu da co-eletrodeposição de cobre e estanho sobre eletrodo de ouro policristalino na presença do surfactante Triton X-100. Instabilidades temporais na forma de oscilações de corrente sob controle potenciostático resultantes da presença de uma região de resistência diferencial negativa no perfil voltamétrico têm sido experimentalmente observadas nesse sistema. Acompanhando essas oscilações de corrente há uma deposição intercalada em multicamadas de diferentes composições (basicamente Cu e CuSn), espessuras e morfologias. Especificamente foram estudadas neste trabalho a variedade dinâmica (i.e., o formato e escala de tempo das oscilações de corrente) e a estrutura e composição dos eletrodepósitos formados. Esse estudo tomou como base o mapeamento das regiões de instabilidade no plano (resistência externa, Rext) x (voltagem aplicada, U) sob diferentes concentrações das espécies eletroativas. Curvas de polarização foram obtidas por meio de experimentos quasi-estacionários de varredura catódica a baixas velocidades. De posse do conhecimento da localização das regiões nas quais oscilações de corrente foram observadas, experimentos estacionários foram realizados, e a morfologia e composição dos depósitos foram investigadas ex-situ por meio de microscopia eletrônica de varredura (MEV) e EDX, respectivamente. / The study of the dynamics self-organization on the solid/liquid interface during the co-electro deposition of copper and tin in the presence of adsorbed surfactant was carried out. Temporal instabilities in form of current oscillations under potentiostatic control resulted from the presence of a negative differential resistance in the voltametric profile has been reported in this system. The electro deposits obtained by this oscillatory regimen exhibit layer-by-layer structure with different compositions of Cu-Sn alloys. In the present work current density (j) versus potential(U) curves and j versus time (t) curves were recorded for the co-electro depositions under a series of external resistances (Rext) and polarization potentials. The characterization of the films were carried out by scanning electron microscope (SEM) and energy dispersive x-ray (EDX) analysis. The results confirm that for different values of external resistance and polarization potentials different compositions of the electro deposited Cu-Sn alloys were obtained.
23

A auto-organização feminista como processo de aprendizagem coletiva: a experiência da Rede Xique-Xique / Feminist self-organization as a collective learning process: experiences from Xique-Xique Network, 2014

Mariana Pereira de Castro 13 March 2014 (has links)
Esta pesquisa apresenta um estudo de caso cujo objetivo é descrever os saberes produzidos no processo de auto-organização de grupos de mulheres da Rede Xique-Xique de Comercialização Solidária, nos municípios de Mossoró, Upanema, Governador Dix-Sept Rosado, Baraúna, Grossos, Tibau e Apodi, no estado do Rio Grande do Norte. Trata-se de uma análise sócio histórica e econômica das categorias discursivas de termos como \'mulheres\', \'trabalho, \'família\' e \'história\', assim como da capacidade de transformação social que estes saberes apresentam. A pesquisa de campo foi guiada essencialmente pelo método da observação participante, com procedimentos aplicados pelo método biográfico, mais especificamente pela história de vida. Sobre a coleta dos dados, foram realizadas 11 entrevistas individuais com as mulheres dos grupos auto-organizados; uma entrevista com a coordenadora do CF8 e uma entrevista coletiva, na qual estavam presentes mulheres participantes de seis grupos da região. Além das entrevistas, foram realizadas visitas aos grupos produtivos, participação em reuniões e seminários promovidos pela Rede Xique-Xique ou instituições parceiras. Para analisar todos os dados registrados, as entrevistas foram transcritas e categorizadas. A análise foi realizada a partir do objetivo apresentado e da referenciação das categorias supracitadas, com o auxílio do Software NVivo10. Nesse sentido, foi possível descrever e apreender que o processo de auto-organização dessas mulheres permite a construção de um ato comunicativo entre estas, que por sua vez possibilita a produção de saberes. Esse ato comunicativo torna-se emancipatório na medida em que se caracteriza como uma prática constante de autorreflexão a respeito dos efeitos da organização produtiva autogerida e contribui assim com a transformação de vida dessas mulheres. Sobre a estrutura textual do presente trabalho, a dissertação está dividida em três capítulos. O primeiro capítulo trata da descrição dos aspectos sócio históricos do estado do Rio Grande do Norte e sua relação constitutiva com a ação atual da Rede Xique-Xique. O capítulo dois descreve a estrutura de princípios ou pilares que sustentam a prática da Rede: agroecologia, economia solidária e feminismo. No capítulo três, com base nas categorias discursivas propostas, analiso as histórias de vidas das mulheres entrevistadas durante o trabalho de campo. Por fim, as considerações finais são apresentadas. / This research presents a case study which aims to describe the knowledge produced in the process of self-organizing groups of women Xique-Xique Network Marketing Partnership located in Mossoró, Upanema, Governador Dix-Sept Rosado, Baraúna, Grossos, Tibau e Apodi in the state of Rio Grande do Norte. It is a historical and socioeconomic analysis of the discursive categories of terms such as \'women\', \'work\', \'family\' and \'history\', as well as the ability to social transformation this knowledge presents. The field research was guided essentially by the method of participant observation with procedures applied by the biographical method, more specifically the history of life. On data collection, 11 individual interviews with women of self-organized groups were conducted; interview with the coordinator of the CF8 and a press conference, in which women from six groups in the region were present. Besides the interviews, visits to productive groups, participation in meetings and seminars sponsored by Xique-Xique Network or partner institutions were conducted. To analyze all the recorded data, the interviews were transcribed and using NVivo10, categorized. The analysis was based on the discursive and historical referencing of the above categories. Thus, it was possible to describe and understand that the process of self-organization of these women allows the construction of a communicative act between them, which in turn enables the production of knowledge. This communicative act becomes emancipatory in that it is characterized as a constant practice of self-reflection about the effects of self-managed productive organization and thus contributes to the transformation of these women\'s lives. On the textual structure of the present paper, it is divided into three chapters. The first chapter presents the description of the historical and social aspects of the state of Rio Grande do Norte and its constitutive relationship with the Xique-Xique Network current action. Chapter two describes the structure of principles that support the practice of the group: agroecology, economic solidarity and feminism. In chapter three, based on the discursive categories proposed, I analyze the life histories of the women interviewed during the field work. Finally, the concluding remarks are presented.
24

Films minces auto-organisés à base de copolymères à blocs de type PS-PLA / Self-organized thin films based on PS-PLA block copolymers

Dirany, Mohammed 17 December 2009 (has links)
Les films minces de copolymères à bloc PS-b-PLA peuvent servir de gabarits pour la fabrication de nano-objets sur une surface. Ce copolymère à bloc doit dans ce cas être organisé sous forme de cylindres de PLA orientés perpendiculairement et arrangés en hexagone dans une matrice de PS sur plusieurs micromètres. Le PLA extrait par hydrolyse conduit alors à un film mince poreux. Dans cette perspective, des films minces ont été préparés par spin-coating d’une solution d’un PS-PLA, de fraction volumique en PLA 0,35. Les analyses en AFM, MEB montrent que les films ainsi préparés présente un état métastable avec une structure nanoséparée avec des cylindres de PLA orientés perpendiculairement et arrangés en hexagone très localement. Il est nécessaire de réorganiser les films pour obtenir une organisation à longue distance. Les recuits thermiques sous vide s’avèrent peu efficace. L’exposition des films à des vapeurs de solvant (THF, acétone et chlorobenzène) entraîne la réorganisation des films. La nature du solvant, le temps d’exposition conditionnent la morphologie observée. Une étude détaillée de ces paramètres permet d’obtenir une organisation optimale pour les applications visées. Une irradiation UV permet d’immobiliser le film sur la surface rendant possible l’extraction du PLA par hydrolyse. Des films de PS à nanoporosité organisés sur plusieurs micromètres peuvent donc être produits. En parallèle, une stratégie de synthèse originale de copolymères diblocs PS-PLA fondée sur la combinaison d’ATRP et du ROP en utilisant le tribromoéthanol comme amorceur commercial a été essayé. Après purification des copolymères synthétisés sur une colonne de silice afin d’éliminer les homopolymères PLA, les différentes morphologies obtenues après dépôt par spin-coating ont été étudiées et des expositions à des vapeurs de solvants ont été réalisées afin d’améliorer l’ordre à grande échelle des films préparés. / Block copolymers thin films (PS-PLA) can be used as templates to fabricate nano-objects on a surface. This block copolymer must be organized in the form of cylinders of PLA oriented perpendicularly and arranged in a hexagonal array in PS matrix over several micrometers. PLA extracted by hydrolysis leads to a porous thin film. In this perspective, thin films were prepared by spin-coating from a solution of PS-PLA, the PLA volume fraction was 0,35. Analysis by AFM, SEM showed that the films prepared after spin-coating has a metastable state with a nanoseparated structure with PLA cylinders oriented perpendicularly and arranged in hexagon very locally. It is necessary to reorganize the films to obtain a long range order. The thermal annealing have been shown to be ineffective. The exposition of films to solvent vapours (THF, acetone and chlorobenzene) improves the reorganization of block copolymers thin films. The solvent nature and exposure time determine the film morphology. With a detailed experimental study of these parameters we determine the experimental conditions to obtain thin films with cylinders of PLA oriented perpendicularly and arranged in hexagonal array over several micrometers (exposure to THF for 4H). UV irradiation immobilizes the film on the surface and therefore the extraction of PLA is possible by hydrolysis. Nanoporous polystyrene thin film organized over several micrometers can be produced. In parallel, original synthesis of PS-PLA based on the combination of ATRP and ROP using commercial dualinitiator tribromoethanol has been tried. After purification of copolymers synthesized on a silica column to remove the PLA homopolymer, the morphologies obtained after spin-coating have been studied and exposition to solvent vapours were performed to improve the film order-scale.
25

Energy-Efficient Self-Organization of Wireless Acoustic Sensor Networks for Ground Target Tracking

Walpola, Malaka J 12 November 2009 (has links)
With the developments in computing and communication technologies, wireless sensor networks have become popular in wide range of application areas such as health, military, environment and habitant monitoring. Moreover, wireless acoustic sensor networks have been widely used for target tracking applications due to their passive nature, reliability and low cost. Traditionally, acoustic sensor arrays built in linear, circular or other regular shapes are used for tracking acoustic sources. The maintaining of relative geometry of the acoustic sensors in the array is vital for accurate target tracking, which greatly reduces the flexibility of the sensor network. To overcome this limitation, we propose using only a single acoustic sensor at each sensor node. This design greatly improves the flexibility of the sensor network and makes it possible to deploy the sensor network in remote or hostile regions through air-drop or other stealth approaches. Acoustic arrays are capable of performing the target localization or generating the bearing estimations on their own. However, with only a single acoustic sensor, the sensor nodes will not be able to generate such measurements. Thus, self-organization of sensor nodes into virtual arrays to perform the target localization is essential. We developed an energy-efficient and distributed self-organization algorithm for target tracking using wireless acoustic sensor networks. The major error sources of the localization process were studied, and an energy-aware node selection criterion was developed to minimize the target localization errors. Using this node selection criterion, the self-organization algorithm selects a near-optimal localization sensor group to minimize the target tracking errors. In addition, a message passing protocol was developed to implement the self-organization algorithm in a distributed manner. In order to achieve extended sensor network lifetime, energy conservation was incorporated into the self-organization algorithm by incorporating a sleep-wakeup management mechanism with a novel cross layer adaptive wakeup probability adjustment scheme. The simulation results confirm that the developed self-organization algorithm provides satisfactory target tracking performance. Moreover, the energy saving analysis confirms the effectiveness of the cross layer power management scheme in achieving extended sensor network lifetime without degrading the target tracking performance.
26

SELF-ORGANIZED STRUCTURES: MODELING POLISTES DOMINULA NEST CONSTRUCTION WITH SIMPLE RULES

Harrison, Matthew, Karsai, Istvan, Wallace, Christopher 04 April 2018 (has links)
The self-organized nest construction behaviors of European paper wasps (Polistes dominula) show potential for adoption in artificial intelligence and robotic systems where centralized control proves challenging. However, P. dominula nest construction mechanisms are not fully understood. The goal of this research was to investigate how P. dominula nest structures stimulate worker actions. Simulation utilities were constructed in C++, C#, and Python. Two models from previous work, a three-dimensional model with weighted actions and a two-dimensional model with simple rule-based actions, were combined in a three-dimensional model with simple rules. Nest construction was simulated with a random selection rule, an age-based rule, a height requirement rule, and a height difference rule. Real and idealized nest data were used to evaluate simulated nests. Structures generated with age- and height-based rules showed more correlation with real and idealized nest structures than randomly-generated structures.
27

Generation of thalamic neurons from mouse embryonic stem cells / マウス胚性幹細胞からの視床神経の分化誘導

Shiraishi, Atsushi 23 January 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20790号 / 医博第4290号 / 新制||医||1025(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 高橋 淳, 教授 井上 治久, 教授 林 康紀 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
28

Organism-Environment Codetermination: The Biological Roots of Enactivism

Corris, Amanda B. 27 September 2020 (has links)
No description available.
29

Semi-formal + Semi-informal City: Looking into a semi-formal approach toward urbanism

Dhingra, Anshumi 25 May 2023 (has links)
No description available.
30

DISTRIBUTED HEBBIAN INFERENCE OF ENVIRONMENT STRUCTURE IN SELF-ORGANIZED SENSOR NETWORKS

SHAH, PAYAL D. 03 July 2007 (has links)
No description available.

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