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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.
201

La matière organique dissoute issue de sols contaminés par des goudrons de houille : vers une meilleure compréhension de sa nature et de sa réactivité / Dissolved organic matter from coal-tar contaminated soils : to a better understanding of its nature, its properties and its evolution

Hanser, Ogier 03 March 2015 (has links)
De nombreuses friches héritées d’activités industrielles révolues présentent des pollutions organiques persistantes (charbon, goudron…). Alors que la réglementation impose un une évaluation du degré de contamination de ces sites, elle ne prend pas en compte les sous-produits de transformation tels que les composés polaires, peu considérés. Pourtant ils se solubilisent dans la phase aqueuse par percolation des eaux météoriques à travers ces surfaces contaminées. Bien que la littérature ciblant la matière organique dissoute (MOD) d’origine naturelle soit abondante, elle n’est pas directement transposable à la MOD issues des friches contaminées, qui reste à définir pour une meilleure compréhension du devenir de la pollution dans ces sites anthropisés. Une approche multi-techniques a été appliquée pour appréhender le plus précisément possible la MOD issue de terres d’anciennes cokeries et usines à gaz, par le biais d’expériences en laboratoire et des dispositifs de terrain (lysimètres). L’étude de ces derniers montre qu’ils contiennent une forte teneur en MOD aromatique, dont les composés aromatiques polycycliques ne représentent qu’une faible proportion de la MOD totale. Des expériences complémentaires ciblant l’influence de certains paramètres (pH et hydrophobicité) suggèrent un lien fort entre le pH et l’organisation spatiale de la MOD, ainsi qu’une diminution de la masse moléculaire apparente avec l’augmentation de l’hydrophobicité. Des expériences de vieillissement artificiel ont montré un enrichissement en produits polaires condensés entraînant leur forte mobilisation par l’eau / A large amount of wastelands inherited from former industrial activities contains persistent organic contamination (coal, coal tar…). While the regulation requires an evaluation of the contamination degree of these soils, it doesn’t take into account the transformation by-products such as polar compounds, poorly studied. Yet they solubilize in aqueous phase by percolation of meteoric waters through these contaminated sites. Despite the fact that literature targeting the fresh DOM is abundant, it is not directly transposable to the anthropogenic DOM coming from wastelands, which still need to be more precisely defined to improve our knowledge of this specific DOM and its evolution over time. A multi-technical approach was developed to comprehend the anthropogenic DOM coming from former coking and gas plant soils, thanks to a combination of laboratory experiments (under controlled conditions) and on field devices (lysimeters). Their study show that they contained high polycyclic aromatic compound (PAC) contents, whose proportions in polar PACs exceed the ones in soil measurements. However, these PACs only consist of a low proportion of the total DOM. Complementary experiences targeting the influence of some parameters (pH, hydrophobicity) show a major hydrophobic characteristic and suggest a strong link between the pH and the spatial DOM organization. Artificial aging experiences show an enrichment in polar compounds leading to their water mobilization
202

Generalization bounds for random samples in Hilbert spaces / Estimation statistique dans les espaces de Hilbert

Giulini, Ilaria 24 September 2015 (has links)
Ce travail de thèse porte sur l'obtention de bornes de généralisation pour des échantillons statistiques à valeur dans des espaces de Hilbert définis par des noyaux reproduisants. L'approche consiste à obtenir des bornes non asymptotiques indépendantes de la dimension dans des espaces de dimension finie, en utilisant des inégalités PAC-Bayesiennes liées à une perturbation Gaussienne du paramètre et à les étendre ensuite aux espaces de Hilbert séparables. On se pose dans un premier temps la question de l'estimation de l'opérateur de Gram à partir d'un échantillon i. i. d. par un estimateur robuste et on propose des bornes uniformes, sous des hypothèses faibles de moments. Ces résultats permettent de caractériser l'analyse en composantes principales indépendamment de la dimension et d'en proposer des variantes robustes. On propose ensuite un nouvel algorithme de clustering spectral. Au lieu de ne garder que la projection sur les premiers vecteurs propres, on calcule une itérée du Laplacian normalisé. Cette itération, justifiée par l'analyse du clustering en termes de chaînes de Markov, opère comme une version régularisée de la projection sur les premiers vecteurs propres et permet d'obtenir un algorithme dans lequel le nombre de clusters est déterminé automatiquement. On présente des bornes non asymptotiques concernant la convergence de cet algorithme, lorsque les points à classer forment un échantillon i. i. d. d'une loi à support compact dans un espace de Hilbert. Ces bornes sont déduites des bornes obtenues pour l'estimation d'un opérateur de Gram dans un espace de Hilbert. On termine par un aperçu de l'intérêt du clustering spectral dans le cadre de l'analyse d'images. / This thesis focuses on obtaining generalization bounds for random samples in reproducing kernel Hilbert spaces. The approach consists in first obtaining non-asymptotic dimension-free bounds in finite-dimensional spaces using some PAC-Bayesian inequalities related to Gaussian perturbations and then in generalizing the results in a separable Hilbert space. We first investigate the question of estimating the Gram operator by a robust estimator from an i. i. d. sample and we present uniform bounds that hold under weak moment assumptions. These results allow us to qualify principal component analysis independently of the dimension of the ambient space and to propose stable versions of it. In the last part of the thesis we present a new algorithm for spectral clustering. It consists in replacing the projection on the eigenvectors associated with the largest eigenvalues of the Laplacian matrix by a power of the normalized Laplacian. This iteration, justified by the analysis of clustering in terms of Markov chains, performs a smooth truncation. We prove nonasymptotic bounds for the convergence of our spectral clustering algorithm applied to a random sample of points in a Hilbert space that are deduced from the bounds for the Gram operator in a Hilbert space. Experiments are done in the context of image analysis.
203

Locating 'home': Strategies of settlement, identity-formation and social change among African women in Cape Town, 1948-2000

Lee, Rebekah January 2002 (has links)
Philosophiae Doctor - PhD / This dissertation constructs a social history of African women in Cape Town from the vantage point of their varied attempts over the last five decades to map 'home' in the urban setting: in the physical structures of their homes; the character of their social and kinship networks; and in the ways a notion of 'place' was re-worked. An historiographical examination of existing research has shown that, especially in the South African context, much scope remains for a regionally specific historical analysis of the urbanisation process, and African women's unique role in it. The use of oral histories and the adoption of a trans-generational interviewing strategy have helped fashion a textured account of African women's settlement strategies, and the underlying social and personal transformations that their design and use suggested. 'First-generational' women, who entered Cape Town at mid-century, led an uncertain and highly regulated urban existence, by virtue of their enforced marginalisation under apartheid. Until the late-1980s, Cape Town retained a distinctive demographic composition, and an historical association as the 'home' of the Coloured population. This made state and local efforts to control the entry and residence of the minority African populace more coercive and successful, at least in the first two decades of apartheid rule. Despite these restrictions, African women constructed and managed a dense set of strategies which affirmed their material livelihoods in the city and increasingly enmeshed their identities in the workings of a modern and commoditised world. However, first-generational women also actively contested these developments to some extent, evident particularly in their efforts to regulate the movement of and compel financial support from their increasingly mobile daughters and granddaughters. Evidence from second and third-generational respondents show a growing reluctance to utilise first-generational women's settlement strategies and the conceptual frameworks which underpinned them. For instance, associational links were increasingly organised along non-racialised lines. Third-generational women's desire to establish residence in other areas of the city, or in other cities entirely, was indicative of a similar dynamic. This was also reflective of their embrace of mobility as an expression of greater economic and social freedoms possible in a post-apartheid world. This dissertation constructs a social history of African women in Cape Town from the vantage point of their varied attempts over the last five decades to locate 'home' in the urban setting. It charts the experiences of a group of women who first moved to Cape Town in the 1940s and 50s, and their children and grandchildren. My focus is on the way in which succeeding generations of women developed differing strategies of settlement, in the context of sometimes dramatic social and political change. The social as well as the physical elements of locating home are key elements in the analysis, including the redefinition of kinship and associational networks, as well as the re-casting of identities and a sense of place. Until the late 1980s, Cape Town retained a distinctive demographic composition, and an historical association as the 'home' of the Coloured- population. This made state and local efforts to control the entry and residence of the minority African populace more coercive and successful, at least in the first two decades of apartheid rule. Rather than painting a comprehensive portrait of urban African life in the apartheid era (1948- 1994), this dissertation hopes to map a few significant dynamics which were manifest in the encounters between a select group of African women and the distinctive terrain of this city during the apartheid years.
204

Understanding Dementia Caregiver Experiences of Burden and Positive Aspects of Caregiving: A Cluster Analytic Approach

Cousins-Whitus, Elizabeth Andrea 04 April 2023 (has links)
No description available.
205

Removal of Saxitoxin and Microcystin when present alone or simultaneously in drinking water plants with different PAC sources

WALKE, DIVYANI 17 May 2023 (has links)
No description available.
206

Etude des non-linéarité photoréfractives dans les composés semi-isolants III-V et II-VI : influence d'une irradiation électronique

Delaye, Philippe 06 April 1993 (has links) (PDF)
Ce manuscrit présente l'étude de l'effet photorefractif dans le proche infrarouge et, plus particulièrement, l'étude des matériaux sensibles dans cette gamme de longueurs d'onde. la première partie du travail a consiste a étudier les matériaux existants, provenant de la microélectronique, le GaAs et l'InP. Les études réalisées, tant expérimentales que théoriques, ont permis de comprendre leurs propriétés et de mettre en évidence leurs limitations, notamment pour les applications dans la gamme de longueurs d'onde autour de 1,3 m. au vu de ces résultats, nous avons propose une technique d'optimisation des performances de gaas utilisant l'irradiation électronique. L'irradiation induit une légère variation du niveau de fermi, qui doit favoriser l'effet photorefractif a 1,3 m. Les résultats obtenus ont montre que l'effet attendu était fortement contrebalance par la création au milieu de la bande interdite, d'un défaut d'irradiation. L'influence directe de ce défaut a été établie grâce au développement d'un modèle théorique de l'effet photorefractif prenant en compte deux niveaux de pièges profonds. En parallèle a cette étude de l'effet d'irradiation, nous avons travaille sur les composes ii-vi, comme le CdTe. Les premiers cristaux étudiés présentent des gains photorefractifs intéressants avec des faisceaux de faible puissance. Ces résultats confirment les promesses de ces cristaux pour une extension de l'effet photorefractif vers 1,5 m. Pour finir, nous présentons une technique d'amplification du gain photorefractif qui utilise l'application d'un champ alternatif carre. une augmentation du gain d'un ordre de grandeur est obtenue.
207

Faculty Senate Minutes March 7, 2016

University of Arizona Faculty Senate 05 April 2016 (has links)
This item contains the agenda, minutes, and attachments for the Faculty Senate meeting on this date. There may be additional materials from the meeting available at the Faculty Center.
208

Faculty Senate Minutes April 2, 2012

University of Arizona Faculty Senate 02 April 2012 (has links)
This item contains the agenda, minutes, and attachments for the Faculty Senate meeting on this date. There may be additional materials from the meeting available at the Faculty Center.
209

O PAC social e urbano na Comunidade Fé em Deus – Belém/PA: a participação como premissa para a execução do trabalho social

BORGES, Odália Lima 07 November 2016 (has links)
Submitted by Hellen Luz (hellencrisluz@gmail.com) on 2018-03-27T17:14:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_PACSocialUrbano.pdf: 3677936 bytes, checksum: b58468d2b6d7422a37262ecbe1a3c44a (MD5) / Approved for entry into archive by Aline Borges (aline@ufpa.br) on 2018-04-10T16:02:40Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_PACSocialUrbano.pdf: 3677936 bytes, checksum: b58468d2b6d7422a37262ecbe1a3c44a (MD5) / Made available in DSpace on 2018-04-10T16:02:41Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_PACSocialUrbano.pdf: 3677936 bytes, checksum: b58468d2b6d7422a37262ecbe1a3c44a (MD5) Previous issue date: 2016-11-07 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho teve por objeto a intervenção urbanística do PAC Social e Urbano na Comunidade Fé em Deus, cujo objetivo foi verificar se o programa garantiu a participação efetiva dos moradores nas ações planejadas, uma vez que o PAC apresentava como diferencial a proposta de participação popular na sua execução, o que o diferenciaria das políticas urbanas centralizadoras e burocráticas historicamente implementadas no país. O estudo se dá a partir da observação in loco, registro fotográfico, consultas a sites oficiais, pesquisa documental e bibliográfica e entrevista, tendo por aporte teórico-metodológico autoras e autores que discutem as políticas de desenvolvimento urbano. A análise realizada nesse estudo aponta que o PAC Urbanização de Assentamentos Precários na Comunidade Fé em Deus reproduziu as políticas de caráter centralizador e burocrático, com o formato de participação institucionalizada e individualizada da população local. / This researh aims to discuss the urban intervention of the Social and Urban PAC in the community "Fé em Deus" and also verify if the program guaranteed the effective participation of the residents in the planned actions, whereas the PAC program has presented as differential the proposal of popular participation in its execution, which would differentiate it from the centralizing and bureaucratic urban policies historically implemented in the country. This study is based on local observation, photographic record, consultations at official websites, documentary and bibliographical research and interviews, with the theoretical-methodological contribution of authors that discuss urban development policies. The results points that PAC Urbanization of Precarious Settlements in the "Fé em Deus" Community used to reproduce a centralized and bureaucratic policie with a institutionalized participation of the local population.
210

O papel dos grupos de interesse no "trade policy making" brasileiro: o caso das negociações Brasil-Argentina para o setor automotivo / The role of interest groups in the brazilian trade policy making: the case of Brazil-Argentina automotive negotiations

Roberta Sayuri Monteiro Sakaguchi 13 April 2011 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Desde a redemocratização do país em 1985 o MRE já vinha se posicionando à favor do diálogo com os mais diversos grupos e entidades sociais. Neste sentido, observou-se ao longo dos últimos anos um aprofundamento da interação com parlamentares, governos estaduais e municipais, empresários, sindicalistas, ONGs e imprensa. A construção de vínculos entre as organizações da sociedade civil críticas das negociações comerciais ao longo da década de 1990 permite falar na criação de um novo campo de ação coletiva transnacional, definido como um espaço de ação política formado por indivíduos e organizações da sociedade civil que participam do processo de elaboração de um conjunto comum de práticas, objetivos e crenças. O que se pode concluir é que diante de um contexto mais competitivo e globalizado, após processo de abertura comercial e intensificação da participação brasileira nas negociações internacionais, a representação dos interesses da classe empresarial teve que se adaptar criando uma nova forma de organização. Desse modo, o presente trabalho visa analisar a crescente interferência de grupos de interesse no processo de tomada de decisão, no que tange aos assuntos de política externa comercial brasileira, tais como as negociações comerciais internacionais por se tratar de um ambiente cujos interesses da classe empresarial mais podem ser afetados. As negociações comerciais internacionais é o ambiente em que a atuação empresarial mais pode ser percebida. As negociações do Mercosul e da ALCA possibilitam observar a participação ativa destes novos atores. Sendo assim, o trabalho apresenta a nova dinâmica de relacionamento entre Estado e grupos da sociedade civil (classe empresarial) para temas ligados a comércio exterior. / Since the democratization of the country in 1985 the Ministry of Foreign Affairs was already positioning itself to promote a dialogue with the various groups and charities. In this sense, it was observed over the past year a further interaction with lawmakers, state and local governments, businessmen, trade unionists, NGOs and media. The building of links between civil society organizations critical of trade negotiations throughout the 1990s allows us to speak on creating a new field of transnational collective action, defined as a space for political action made up of individuals and civil society organizations that participate the process of developing a common set of practices, beliefs and goals. What can be concluded is that before a more competitive and globalized, after opening up of trade and intensification of the Brazilian participation in international negotiations, representing the interests of the business class had to adapt by creating a new form of organization. Thus, this study aims to examine the growing interference of interest groups in decision-making process, with respect to matters of Brazilian foreign trade policy, such as international trade negotiations because it is an environment whose interests the business class more may be affected. International trade negotiations are the environment in which business activity can be more noticeable. Negotiations of the Mercosur and the FTAA allow you to observe the active participation of new actors. Thus, the paper presents a new dynamic relationship between state and civil society groups (business class) for issues related to foreign trade.

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