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Hung, Ling-chun. "The radioisotope unit radon analysis laboratory and its application to radon mitigation studies /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20897480.
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Gaskin, Janet. "Radon and Lung Cancer." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39003.
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Background: Lung cancer was the fifth leading cause of mortality globally in 2010, and the leading cause of cancer mortality in Canada, representing 26% of all cancer deaths for both men and women in 2017. Radon is a very modifiable environmental exposure that is the second most important cause of lung cancer.
Objectives: The objectives of this thesis are to quantify the lung cancer burden associated with residential radon and to identify the most cost effective mitigation options to reduce residential radon in Canada.
Methods: The global burden of lung cancer mortality attributable to radon in 2012 was estimated from the 66 countries for which a representative national radon survey was available, using several different models for excess relative risk (ERR) of lung cancer from radon studies. Cost-utility analyses are conducted for 20 practical radon interventions scenarios to reduce residential radon exposures in new and existing housing in Canada, each province/territory and 17 census metropolitan areas. A societal perspective and a lifetime horizon are adopted. A Markov cohort model and a discrete event simulation are used to model residents by household, based on a period-life table analysis, at a discount rate of 1.5%.
Results: The estimates of the global median PAR were consistent, ranging from 16.5% to 13.6% for the three ERR models based on miners, and the mean estimates of PAR for Canada ranged from 16.3% to 14.6%. It is very cost effective to install radon preventive measures in new construction compared to no radon control in all regions across Canada. At a radon mitigation threshold of 100 Bq/m3, the sequential analysis recommends the combination of the activation of preventive measures in new housing with the mitigation of existing housing at current testing and mitigation rates for cost effectiveness thresholds between 51,889 and 92,072 $/QALY for Canada, between 27,558 and 85,965 $/QALY for Manitoba, and between 15,801 and 36,547 $/QALY for the Yukon. The discounted ICER for screening and mitigation of existing housing at current rates relative to no radon control measures is 62,451 (66,421) $/QALY using a Markov cohort model (discrete event simulation model) for mitigation of housing above a threshold of 200 Bq/m3, and is 58,866 (59,556) $/QALY using a Markov cohort model (discrete event simulation model) for mitigation of housing above a threshold of 100 Bq/m3.
Conclusions: Cost effective residential radon interventions should be implemented across Canada to reduce exposures to this very modifiable cause of lung cancer and to help reduce the increasing lung cancer burden in an ageing Canadian population.
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Goncharov, Fedor. "Transformations de Radon pondérées et leurs applications." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLX029/document.
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Cette thèse est consacrée à l'étude des problèmes inverses des transformations de Radon pondérées dans les espaces euclidiens. D'une part, nos études sont motivées par l'application des transformations de Radon pondérées pour différentes tomographies, par exemple en tomographie d'émission (PET, SPECT), en tomographie de fluorescence et en tomographie optique. En particulier, nous développons une nouvelle approche de reconstruction pour les tomographies en 3D, où les données sont modélisées par des transformations des rayons pondérées le long des rayons parallèles à un plan fixe. À cet égard, nos résultats contiennent : des formules pour la réduction des transformées des rayons pondérés en transformées de Radon le long de plans en 3D ; un analogue de la formule d'inversion approximative de Chang et un analogue de l'algorithme d'inversion itératif de type Kunyansky pour les transformations de Radon pondérées en multidimension ; des reconstructions numériques à partir de données simulées et réelles. D'autre part, nos études sont motivées par des problèmes mathématiques liés aux transformations susmentionnées. Plus précisément, nous poursuivons l'étude de l'injectivité et de la non-injectivité des transformations de Radon et des transformations des rayons pondérées en multidimension et construisons une série de contre-exemples à l'injectivité de ces dernières. Ces contre exemples sont intéressants et, dans un certain sens, inattendus parce qu'ils sont proches des cas où ces transformations deviennent injectives. En particulier, par l'une de nos constructions, nous donnons des contre-exemples à des théorèmes d'injectivité bien connus pour les transformations des rayons pondérées (Quinto (1983), Markoe, Quinto (1985), Finch (1986), Ilmavirta (2016)) lorsque les hypothèses de régularité des poids sont légèrement relaxées. Par ce résultat, nous montrons en particulier que les hypothèses de régularité sur les poids sont cruciales pour l'injectivité et qu'il y a une "brisure" de cette dernière si les hypothèses sont légèrement affaibliesThis thesis is devoted to studies of inverse problems for weighted Radon tranforms in euclidean spaces. On one hand, our studies are motivated by applications of weighted Radon transforms in different tomographies, for example, in emission tomographies (PET, SPECT), flourescence tomography and optical tomography. In particular, we develop a new reconstruction approach for tomographies in 3D, where data are modelized by weighted ray transforms along rays parallel to some fixed plane. In this connection our results include: formulas for reduction of the aforementioned weighted ray transforms to weghted Radon transforms along planes in 3D; an analog of Chang approximate inversion formula and an analog of Kunyansky-type iterative inversion algorithm for weighted Radon transforms in multidimensions; numercal reconstructions from simulated and real data. On the other hand, our studies are motivated by mathematical problems related to the aforementioned transforms. More precisely, we continue studies of injectivity and non-injectivity of weighted ray and Radon transforms in multidimensions and we construct a series of counterexamples to injectivity for the latter. These counterexamples are interesting and in some sense unexpected because they are close to the setting when the corresponding weighted ray and Radon transforms become injective. In particular, by one ofour constructions we give counterexamples to well-known injectivity theorems for weighted ray transforms (Quinto (1983), Markoe, Quinto (1985), Finch (1986), Ilmavirta (2016)) when the regularity assumptions on weights are slightly relaxed. By this result we show that, in particular, the regularity assumptions on weights are crucial for the injectivity and there is a breakdown of the latter if the assumptions are slightly relaxed
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Webber, James. "Radon transforms and microlocal analysis in Compton scattering tomography." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/radon-transforms-and-microlocal-analysis-in-compton-scattering-tomography(c1ad3583-01ce-4147-8576-2e635090cb15).html.
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In this thesis we present new ideas and mathematical insights in the field of Compton Scattering Tomography (CST), an X-ray and gamma ray imaging technique which uses Compton scattered data to reconstruct an electron density of the target. This is an area not considered extensively in the literature, with only two dimensional gamma ray (monochromatic source) CST problems being analysed thus far. The analytic treatment of the polychromatic source case is left untouched and while there are three dimensional acquisition geometries in CST which consider the reconstruction of gamma ray source intensities, an explicit three dimensional electron density reconstruction from Compton scatter data is yet to be obtained. Noting this gap in the literature, we aim to make new and significant advancements in CST, in particular in answering the questions of the three dimensional density reconstruction and polychromatic source problem. Specifically we provide novel and conclusive results on the stability and uniqueness properties of two and three dimensional inverse problems in CST through an analysis of a disc transform and a generalized spindle torus transform. In the final chapter of the thesis we give a novel analysis of the stability of a spindle torus transform from a microlocal perspective. The practical application of our inversion methods to fields in X-ray and gamma ray imaging are also assessed through simulation work.
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Hung, Ling-chun, and 孔令臻. "The radioisotope unit radon analysis laboratory and its application toradon mitigation studies." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31220927.
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Breton, Daniel James. "Radionuclide Fluxes in Glaciers and Seasonal Snowpack." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/BretonDJ2004.pdf.
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Johnstone, Maria Magdalena. "Radon remediation : an analysis of dose-reduction, durability and effectiveness." Thesis, University of Northampton, 2002. http://nectar.northampton.ac.uk/2813/.
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Radon is a colourless, odourless, inert, radioactive gas found in Group 8 of the Periodic Table; it is formed by the decay of uranium in soils and rocks. The half-life of radon is 3.8 days. Radon, in the built environment, is the second largest cause of lung cancer after cigarette smoking and is responsible for 3-5% of the UK cancer deaths. Radon can accumulate in workplaces to levels (400 Bq.m3), above which action is required under UK legislation by employers to remediate so as to reduce levels and lower the risk to human health. The remediation and post-remediation research programme in the NI-IS properties in Northamptonshire is perhaps the most mature in the UK, commencing in 1993. This thesis includes a review of the main remediation projects in National Health Service (NHS) properties in Northamptonshire. Data has been obtained from a range of sources, post-remediation, to enable a cost-effectiveness assessment. Using direct radon measurements and questionnaires, to determine occupancy, dose reduction has been calculated for all members of staff in the remediated venues. The reduction in dose is lower than the reduction in radon. The trends in radon levels post-remediation have been investigated night-time levels are reduced more than daytime levels and this has a clear implication for dose to staff The effective lifetime of the remediation systems has been investigated. Remediation systems, operated through a clear management system, have been found to remain effective up to eight years after installation. A Decision Support System to support radon management in the workplace is proposed as well as suggestions for future research
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Kuchling, Peter [Verfasser]. "Analysis and Dynamics on the Cone of Discrete Radon Measures / Peter Kuchling." Bielefeld : Universitätsbibliothek Bielefeld, 2019. http://d-nb.info/1199005193/34.
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Sajja, Mounika. "Correlation between Indoor Radon Concentrations and Hydraulic Fracturing in Ohio." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1494633736877779.
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Hielscher, Ralf. "The Radon transform on the rotation group inversion and application to texture analysis /." Doctoral thesis, [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=985235330.
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Černý, Petr. "Ekonomické hodnocení ozdravného protiradonového opatření u rodinných domů." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-86036.
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The aim of the thesis is to valuate economic effectivity of radon mitigation countermeasures co-financed by the state applied in family houses which display high radon level. Feasibility of the mitigation is analysed without concering financing source. Furthermore, the project is valuated from the point of view of the house owner and from the state's point of view. Presence of residental radon is increasing lung cancer probability, radon has notable healt effects. Costs and benefit of the hypothetic project are vauated in CBA analysis. The author finds the project unfeasible. CBA is discussed as a suitable economic tool for fiding alternative technological method aiming to social effectivity. Providing feasible change of remediation parametres caused positive social value of the project, socioeconomic flow in the state point of view would remain negative. Therefore, state participation on the radon mitigation countermeasures of private family houses is not reccomended.
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Wade, Jeremy. "Summability of Fourier orthogonal expansions and a discretized Fourier orthogonal expansion involving Radon projections for functions on the cylinder /." Connect to title online (Scholars' Bank) Connect to title online (ProQuest), 2009. http://hdl.handle.net/1794/10245.
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Salih, Isam M. Musa. "Radon in natural waters : Analytical Methods; Correlation to Environmental Parameters; Radiation Dose Estimation; and GIS Applications." Doctoral thesis, Linköpings universitet, Medicinsk radiofysik, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5221.
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Investigations of radon in natural water and its relation to physical and chemical parameters are outlined in this thesis. In particular, a method for measuring 222Rn in water at low concentrations (~20 mBq.l-1) is described, followed by discussions concerning the design and its application to study both radon and parameters influencing radon levels in natural waters. A topic considered is the impact of fluoride and other aquatic parameters on radon in water. Moreover, variables such as uranium series radionuclides and stable elements in water, bedrock and sediment radioactivity and geology are investigated in two case studies. This was performed by employing radiometric-, chemical-, statistical- and GIS & geostatistical- analyses. The general water chemistry and presence of some elements such as fluoride was observed to influence radon levels in water. Health aspects of radon in drinking water are discussed based on radiation dose assessments. The radiation doses are compared with and added to doses incurred from ingestion of uranium, radium and polonium isotopes in drinking water and inhalation of radon in air in order to estimate total exposures for different age categories. The results may have a potential for future epidemiological studies.
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Galigekere, Ramesh R. "New algorithms for image analysis, compression and 2-D spectrum estimation in the Radon space." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0002/NQ39785.pdf.
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Killip, Ian Richmond. "Radon levels in dwellings in chalk terrain : development and analysis of distributional and causal models." Thesis, University of Brighton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246824.
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This thesis investigates the range, distribution and causes of high radon levels in dwellings in the Brighton area of Southeast England. Indoor radon levels were measured in more than 1000 homes. The results show that high radon levels can arise in an area previously considered to offer low radon potential from local geological sources. Climate and building-related factors were found to affect significantly the radon levels in dwellings. Multiple regression was used to determine the influence of the various factors on indoor radon levels and an empirical model developed to predict indoor radon levels. The radon hazard, independent of building-related effects, was determined for each surveyed location by adjusting the radon measurement to that expected on the ground floor of a 'model' dwelling. This standardised set of radon levels was entered into a geographical information system (GIS) and related to surface geology. The geometric mean radon level for each lithological unit was plotted to produce a radon hazard map for the area. The highest radon levels were found to be associated with the youngest Chalk Formations, particularly where they meet overlying Tertiary deposits, and with Clay-with-Flints Quaternary deposits in the area. The results were also converted to the radon activity equivalent to that expected from the NRPB's standard dual-detector dwelling survey method and analysed by lognormal modelling to estimate the proportion of dwellings likely to exceed the UK Action Level of 200 Bq/m3 for each lithological unit. The likely percentages of dwellings affected by radon thus obtained were mapped to lithological boundaries to produce a radon potential map. The radon hazard map and the empirical radon model facilitate the prediction of radon levels in dwellings of comparable construction and above similar geology and should further the understanding of the behaviour of radon gas in buildings to allow indoor radon concentrations to be controlled. The radon potential map is directly comparable with those produced by NRPB and BGS and can be used to assist in environmental planning and development control.
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Kennedy, Christine. "Evaluating health interventions : a comparison of cost-benefit analysis and cost-effectiveness analysis employing radon-induced lung cancer prevention." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365808.
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Petraki, Ermioni. "Electromagnetic radiation and Radon-222 gas emissions as precursors of seismic activity." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/12872.
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Earthquakes are amongst the most destructive of natural phenomena and have been the subject of significant research effort over many decades, to predict the onset of seismic events. Electromagnetic emissions detected prior to earthquakes provide a potential data source for seismic predictions and research suggests that specific pre-seismic electromagnetic activity can be directly related to specific earthquakes although it is still an open issue as to the precise links between these electromagnetic emissions and subsequent earthquakes. In this research, findings of the long memory or the self-organization of several pre-earthquake MHz electromagnetic time-series provide significant outcomes regarding the earthquake prediction. It is also recognised that enhanced radon gas emission has an equally long history as being associated with seismic activity. In general, several anomalous soil radon emissions have been observed prior to earthquakes and this has been recorded all over the world. The abnormal soil radon exhalation from the interior of the earth has been associated with earthquakes and is considered as an important field of research. The research reported in this thesis compared and contrasted the merits of combining electromagnetic emission data and radon exhalation data as precursors of earthquakes with the aim of enhancing earthquake prediction methodology. The findings from the long-memory analysis of radon disturbances in the soil indicated a very significant issue: the radon disturbances in the soil prior to earthquakes exhibit similar behaviour as the MHz RF disturbances of general failure. So, the radon precursors and the MHz electromagnetic correspond to the same pre-earthquake phase. Geological explanations were proposed in view of the asperity model. Persistent and anti-persistent MHz anomalies were due to the micro-cracking of the heterogeneous medium of the earth's crust which may have led the system's evolution towards the global failure. Fractal methods have been used on historical data, to investigate MHz electromagnetic time-series spectra on emissions preceding major earthquakes over the period 2007 to 2014 and the characteristics of enhanced radon emissions have been studied over the period 2008 to 2015 for seismic events occurring in the Aegean Region. It has been found that both the electromagnetic emissions and the radon exhalation data exhibit similar fractal behaviour and are associated with impending seismic activity. Hence both phenomena are relevant to earthquake predictions and should both be employed in any systematic approach to this problem as the varying geological and geographic conditions under which earthquakes can occur, might preclude one or other data from being measurable. According to the several techniques applied in this thesis, all should be employed in sequential steps, albeit the power-law spectral fractal analysis is the most significant to trace long-memory patterns of 1/f processes as those of the processes of earthquakes.
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Donelan, Jack E. "Groundwater-Surface Water Interaction in the Kern River| Estimates of Baseflow from Dissolved Radon Analysis and Hydrograph Separation Techniques." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10841176.
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Geochemical mixing methods utilizing 222Rn and chloride and statistical hydrograph separation techniques were carried out in an attempt to understand baseflow dynamics in a section of the Kern River in the Sierra Nevada of Southern California. 222Rn has become a valuable tool for evaluating groundwater inflow to a river, particularly when groundwater and surface water have similar major ion geochemistry. When using geochemical methods it is important to minimize uncertainty through comparison with separate tracers and techniques, though this is complicated in this setting. Snow melt discharge and regulation of natural river flow cause hydrograph-based techniques to suffer from inaccuracies. Geochemical mixing using major ions and stable isotopes are complicated by the chemical similarity between surface water and groundwater. 222Rn is a powerful tool to elucidate this relationship in this setting if major uncertainties, like rate of radon degassing and parafluvial and hyporheic radon production can be constrained.
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K, C. Santosh. "Graphics Recognition using Spatial Relations and Shape Analysis." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL096N/document.
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Dans l’état de l’art actuel, la reconnaissance de symboles signifie généralement la reconnaissance des symboles isolés. Cependant, ces méthodes de reconnaissance de symboles isolés ne sont pas toujours adaptés pour résoudre les problèmes du monde réel. Dans le cas des documents composites qui contiennent des éléments textuels et graphiques, on doit être capable d’extraire et de formaliser les liens qui existent entre les images et le texte environnant, afin d’exploiter les informations incorporées dans ces documents.Liés à ce contexte, nous avons d’abord introduit une méthode de reconnaissance graphique basée sur la programmation dynamique et la mise en correspondance de caractéristiques issues de la transformée de Radon. Cette méthode permet d’exploiter la propriété de cette transformée pour inclure à la fois le contour et la structure interne des formes sans utiliser de techniques de compression de la représentation du motif dans un seul vecteur et qui pourrait passer à côté d’informations importantes. La méthode surpasse en performances les descripteurs de forme de l’état de l’art, mais reste principalement adapté pour la reconnaissance de symboles isolés seulement. Nous l’avons donc intégrée dans une approche complètement nouvelle pour la reconnaissance de symboles basé sur la description spatio-structurelle d’un «vocabulaire» de primitives visuelles extraites. La méthode est basée sur les relations spatiales entre des paires de types étiquetés de ce vocabulaire (dont certains peuvent être caractérisés avec le descripteur mentionné précédemment), qui sont ensuite utilisées comme base pour construire un graphe relationnel attribué (ARG) qui décrit des symboles. Grâce à notre étiquetage des types d’attribut, nous évitons le problème classique NP-difficile d’appariement de graphes. Nous effectuons une comparaison exhaustive avec d’autres modèles de relations spatiales ainsi qu’avec l’état de l’art des approches pour la reconnaissance des graphismes afin de prouver que notre approche combine efficacement les descripteurs statistiques structurels et globaux et les surpasse de manière significative.Dans la dernière partie de cette thèse, nous présentons une approche de type sac de caractéristiques utilisant les relations spatiales, où chaque paire possible primitives visuelles est indexée par sa configuration topologique et les types visuels de ses composants. Ceci fournit un moyen de récupérer les symboles isolés ainsi que d’importantes parties connues de symboles en appliquant soit un symbole isolée comme une requête soit une collection de relations entre les primitives visuelles. Finalement, ceci ouvre des perspectives vers des processus de reconnaissance de symboles fondés sur le langage naturelIn the current state-of-the-art, symbol recognition usually means recognising isolated symbols. However, isolated symbol recognition methods are not always suitable for solving real-world problems. In case of composite documents that contain textual and graphical elements, one needs to be able to extract and formalise the links that exist between the images and the surrounding text, in order to exploit the information embedded in those documents.Related to this context, we first introduce a method for graphics recognition based on dynamic programming matching of the Radon features. This method allows to exploit the Radon Transform property to include both boundary and internal structure of shapes without compressing the pattern representation into a single vector that may miss information. The method outperforms all major set of state-of-the-art of shape descriptors but remains mainly suited for isolated symbol recognition only. We therefore integrate it in a completely new approach for symbol recognition based on the spatio-structural description of a ‘vocabulary’ of extracted visual primitives. The method is based on spatial relations between pairs of labelled vocabulary types (some of which can be characterised with the previously mentioned descriptor), which are further used as a basis for building an attributed relational graph (ARG) to describe symbols. Thanks to our labelling of attribute types, we avoid the general NP-hard graph matching problem. We provide a comprehensive comparison with other spatial relation models as well as state-of-the-art approaches for graphics recognition and prove that our approach effectively combines structural and statistical descriptors together and outperforms them significantly.In the final part of this thesis, we present a Bag-Of-Features (BOFs) approach using spatial relations where every possible pair of individual visual primitives is indexed by its topological configuration and the visual type of its components. This provides a way to retrieve isolated symbols as well as significant known parts of symbols by applying either an isolated symbol as a query or a collection of relations between the important visual primitives. Eventually, it opens perspectives towards natural language based symbol recognition process
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Catalan, Vanessa Spurll. "Analysis of the combined primary data from case-control studies of residential radon and lung cancer : a pilot study of three North-American sites." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0003/NQ44380.pdf.
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Kappke, Jaqueline. "Medidas das concentrações de rádio em águas minerais disponíveis à venda no Brasil." Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/524.
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CAPESEste trabalho apresenta os resultados da pesquisa sobre medidas da atividade de 226Ra em águas minerais engarrafadas compradas em estabelecimentos comerciais do Brasil. As medidas foram realizadas no Laboratório de Física Nuclear Aplicada da Universidade Tecnológica Federal do Paraná em cooperação com o Centro de Desenvolvimento e Tecnologia Nuclear (CDTN) da Comissão Nacional de Energia Nuclear (CNEN). O trabalho avalia a possibilidade do uso do equipamento RAD7 (Durridge Company) para medir a atividade de 226Ra em equilíbrio com 222Rn presente nas amostras de águas em nível compatível com 0,1Bq/L, o que significa uma precisão superior à prática usual do equipamento. Além disso, a pesquisa fornece o erro mínimo de medida da concentração de atividade do rádio possível de ser atingida com o uso do equipamento RAD7. A principal dificuldade encontrada na técnica desenvolvida foi diminuir os erros associados às medidas. Para desenvolver a metodologia otimizada foram realizados diversos testes que propiciaram a diminuição dos erros e asseguraram uma técnica inovadora para medidas de baixas concentrações de 226Ra em água, com o uso do detector eletrônico de radônio RAD7. O arranjo experimental foi baseado no detector eletrônico de radônio RAD7 e as medidas foram realizadas utilizando o kit RAD H2O que permite identificar a atividade de concentração do 222Rn em pequenas amostras de 40mL e 250mL. Os resultados mostraram que o erro mínimo ficou entre 0,02 a 0,07 Bq/L o que configura uma diminuição considerável e importante nos erros associados às amostras de baixas concentrações. Quando aplicada a metodologia otimizada e proposta, foi possível concluir que todas as amostras analisadas apresentaram valores abaixo que os estabelecidos pelas normas e recomendações e que os valores encontrados para as amostras possuem ordem de grandeza semelhante às encontradas na literatura. Desta forma, foi possível concluir que o detector eletrônico de radônio RAD7 pode ser utilizado nas medidas de 226Ra em águas para concentrações menores que 0,1 Bq/L, mas que para isto deve ser utilizada uma técnica como esta desenvolvida para otimizar o procedimento.
This thesis presents the survey results of measuring the activity of 226Ra in bottled mineral waters purchased in Brazilian market. The measurements were performed at the Laboratory of Applied Nuclear Physics at Federal Technological University of Paraná in cooperation with the Centre for Development and Nuclear Technology (CDTN) of the National Nuclear Energy Commission (CNEN). The study evaluates the possibility of using RAD7 equipament (Durridge Company) in order to measure 226Ra activity in equilibrium with 222Rn present in water samples at a level compatible with 0.1 Bq/L, which means greater accuracy than the usual practice of the equipment. Furthermore, the search provides the minimum error of radio activity concentration that can be achieved using the RAD7 equipament. The main difficulty of this work was to reduce the associated errors to the measure. To develop the optimized methodology were performed several tests that enabled the reduction of errors and ensure an innovative technique for measuring low concentrations of 226Ra in water, using the RAD7 radon electronic¬ detector. The experimental setup was based on the RAD7 and measurements were performed using the RAD H2O kit that identifies the activity concentration of 222Rn in small samples of 250mL. The results showed that the minimum error ranged from 0.02 to 0.07 Bq/L which constitutes a considerable and significant reduction in errors associated with low concentrations samples. When applied the optimized methodology proposed, it was concluded that all the samples had values below the established standards and recommendations and that the values found for the samples have similar order of magnitude to those found in the literature. Thus, the RAD7 radon detector electronics can be used in measurements of 226Ra in water at concentrations below 0,1 Bq/L, but for that, the technique developed in order optimize the procedure should be used.
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Sanja, Kostadinova. "Some classes of integral transforms on distribution spaces and generalized asymptotics." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2014. https://www.cris.uns.ac.rs/record.jsf?recordId=87772&source=NDLTD&language=en.
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In this doctoral dissertation several integral transforms are discussed.The first one is the Short time Fourier transform (STFT). We present continuity theorems for the STFT and its adjoint on the test function space K1(ℝn) and the topological tensor product K1(ℝn) ⊗ U(ℂn), where U(ℂn) is the space of entirerapidly decreasing functions in any horizontal band of ℂn. We then use such continuity results to develop a framework for the STFT on K'1(ℝn). Also, we devote one section to the characterization of K’1(ℝn) and related spaces via modulation spaces. We also obtain various Tauberian theorems for the short-time Fourier transform.Part of the thesis is dedicated to the ridgelet and the Radon transform. We define and study the ridgelet transform of (Lizorkin) distributions and we show that the ridgelet transform and the ridgelet synthesis operator can be extended as continuous mappings Rψ : S’0(ℝn) → S’(Yn+1) and Rtψ: S’(Yn+1) → S’0(ℝn). We then use our results to develop a distributional framework for the ridgelet transform that is, we treat the ridgelet transform on S’0(ℝn) via a duality approach. Then, the continuity theorems for the ridgelet transform are applied to discuss the continuity of the Radon transform on these spaces and their duals. Finally, we deal with some Abelian and Tauberian theorems relating the quasiasymptotic behavior of distributions with the quasiasymptotics of the its Radon and ridgelet transform.The last chapter is dedicated to the MRA of M-exponential distributions. We study the convergence of multiresolution expansions in various test function and distribution spaces and we discuss the pointwise convergence of multiresolution expansions to the distributional point values of a distribution. We also provide a characterization of the quasiasymptotic behavior in terms of multiresolution expansions and give an MRA sufficient condition for the existence of α-density points of positive measures.U ovoj doktorskoj disertaciji razmotreno je nekoliko integralnih transformacija. Prva je short time Fourier transform (STFT). Date su i dokazane teoreme o neprekidnosti STFT i njena sinteza na prostoru test funkcije K1(ℝn) i na prostoru K1(ℝn) ⊗ U(ℂn), gde je U(ℂn) prostor od celih brzo opadajućih funkcija u proizvoljnom horizontalnom opsegu na ℂn. Onda, ovi rezultati neprekidnosti su iskorišteni za razvijanje teorije STFT na prostoru K’1(ℝn). Jedno poglavlje je posvećeno karakterizaciji K’1(ℝn) sa srodnih modulaciskih prostora. Dokazani su i različiti Tauberovi rezultata za STFT. Deo teze je posvećen na ridglet i Radon transformacije. Ridgelet transformacija je definisana na (Lizorkin) distribucije i pokazano je da ridgelet transformacija i njen operator sinteze mogu da se prošire kako neprekidna preslikava Rψ : S’0(ℝn) → S’(Yn+1) and RtΨ: S’(Yn+1) → S’0(ℝn). Ridgelet transformacija na S’0(ℝn) je data preko dualnog pristupa. Naše teoreme neprekidnosti ridgelet transformacije su primenjene u dokazivanju neprekidnosti Radonove transformacije na Lizorkin test prostorima i njihovim dualima. Na kraju, dajemo Abelovih i Tauberovih teorema koji daju veze izmedju kvaziasimptotike distribucija i kvaziasimptotike rigdelet i Radonovog transfomaciju.Zadnje poglavje je posveceno multirezolucijskog analizu M - eksponencijalnih distrubucije. Proucavamo konvergenciju multirezolucijkog razvoja u razlicitih prostori test funkcije i distribucije i razmotrena je tackasta konvergencija multirezolucijkog razvoju u tacku u distributivnog smislu. Obezbedjena je i karakterizacija kvaziasimptotike u pogled multirezolucijskog razvoju i dat dovoljni uslov za postojanje α-tacka gustine za pozitivne mere.
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Mafra, Karina Cristina. "Medidas da concentração de Radônio-222 em água de poço e solo da região do Pinheirinho em Curitiba e proposta de mitigação da água." Universidade Tecnológica Federal do Paraná, 2011. http://repositorio.utfpr.edu.br/jspui/handle/1/362.
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Mais de 50% da dose de radiação efetiva anual recebida por um ser humano está relacionada com o Radônio e seus produtos. Os principasis mecanismos que levam o Radônio no interior das residências são a emanação do solo e a liberação do Radônio na água. Esse trabalho apresenta uma proposta de mitigação, método para redução de Radônio-222 em níveis de água de poço, utilizando o processo de aeração da água e medidas da concentração de Radônio -222 nas águas e solo. As amostras foram coletadas em poço e solo na região do Pinheirinho em Curitiba, Brasil. As medidas foram realizadas durante o período de Fevereiro a Junho de 2011, sendo analisadas em média dez amostras de cada coleta de água, entre elas oito sob o processo de aeração. As medidas foram obtidas com a câmara de ionização Radon Professional Monitor (AlfaGUARD), aparelho que verifica a concentração de Radônio na faixa de 2 - 2x106 Bq/L, ajustado em um fluxo de 0,5L/min, em um tempo aproximado de 60 minutos, no Laboratório de Radiações Ionizantes da Universidade Tecnológica Federal do Paraná (UTFPR). Os níveis de concentração de Radônio-222 foram medidos através do software AlfaEXPERT, e formulações adequadas caracterizaram a concentração desse gás em água corrigindo o tempo de decaimento devido ao atraso da coleta das amostras em relação às medições. O método de mitigação utilizado foi o de aeração, chamado Aeração Difusora, na qual ocorre a gaseificação da água em um processo de injeção de ar por um aerador conectado em uma placa porosa durante um período de 24 horas em 4 dias, já que a meia-vida do Radônio é cerca de 3,82 dias, para a diminuição da concentração de Radônio-222 nas amostras. Inicialmente as amostras apresentaram concentrações de Radônio-222
de aproximadamente 20 Bq/L, nível acima de 11,11 Bq/L recomendado pela USEPA (Agência de Proteção Ambiental dos Estados Unidos). Após aplicar a medida de mitigação nessas amostras de água, as concentrações de Radônio-222 diminuíram satisfatoriamente e ficaram abaixo do valor esperado pelo decaimento natural do gás.More than 50% of the effective annual radiation dose received by a human being is related to the Radon and its progeny. Among main mechanisms that bring Radon inside the dwelling are the soil emanation and radon release from the water. This present work represents a proposal of mitigation, method to reduce Radon-222 levels in well water, using the process of water aeration and measurements of Radon-222 in the water and soil. Samples were collected in a pit and soil in the region of "Pinheirinho" in the city of "Curitiba" Brazil. The Measurements were taken during the period of February till June of 2011, being analyzed by an average of ten samples of each water collected, among them eight were under the process of aeration. The measurements were obtained with ionization chamber Randon Professional Monitor (AlfaGUARD), a device that checks concentrations of Radon in the range of 2-2x106 Bq/L, adjusted in a flow of 0.5L/min, with approximate time of 60 minutes, in the laboratory for Ionizing Radiation of the Univeristy " Federal do Parana" (UTFPR). The levels of concentration of Radon-222 were measured by the software called AlfaEXPERT, and suitable formulations characterized the concentration of this gas in the water by correcting the time decay due to the delay in the collection of samples for measurements. The method of mitigation used was aeration, called Diffusing Aeration, in which there is the gasification of water in a process that injects air by an aerator connected in a porous plate during a period of 24 hours in 4 days, since the half life of Radon is approximately 3,82 days, for the reduction of the concentration of Radon-222 on samples. Initially samples had concentrations of Radon-222 aproximately from 20 Bq/L, a level above 11.11 Bq/L recomended by USEPA (United States Enviromental Protection Agency). After Applying the measurements to mitigate these samples of water, the concentration of Radono-222 decreased satisfactorily and remained below the expected value by the natural decaying of the water.
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Corrêa, Janine Nicolosi. "Avaliação dos níveis de concentração de radônio em ambientes e águas de poços no estado do Paraná." Universidade Tecnológica Federal do Paraná, 2011. http://repositorio.utfpr.edu.br/jspui/handle/1/1297.
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CNENTendo em vista o crescente interesse dos organismos internacionais e nacionais em se conhecer os níveis de radônio no ar, em águas, principalmente em poços, e a escassez destes dados em esfera nacional, o grupo de pesquisa em radiações da UTFPR, em colaboração com o Centro de Desenvolvimento da Tecnologia Nuclear (CDTN / CNEN) e com o Instituto de Radioproteção e Dosimetria (IRD / CNEN) tem mantido uma parceria onde se realizam medidas de radônio no ar, solos e águas. Estas medidas têm sido feitas pelo grupo desde 2003 e o laboratório especializou-se em medidas no ar, por meio de detectores do estado sólido e em solo e água, por meio de equipamento eletrônico de medidas instantâneas. O objetivo desta tese é avaliar a os níveis de concentração de radônio 222Rn em residências e postos de trabalho (indoor) no estado do Paraná, mais especificamente na região metropolitana de Curitiba e verificar os níveis de concentração de 222Rn em águas de poços desta região. O trabalho apresenta os resultados das concentrações de 222Rn em ambientes residenciais, postos de trabalho e em águas de poços da região. As medidas indoor foram feitas por meio de detectores do estado sólido CR-39. A densidade de traços por cm2 para cada detector foi determinada. Os cálculos das concentrações de 222Rn nos ambientes foram feitos a partir de metodologia de calibração do sistema detector, desenvolvida especificamente para estas medidas. O trabalho de calibração foi desenvolvido em conjunto com o CDTN a partir de irradiações feitas no National Institute of Radiological Sciences (NIRS). As concentrações de 222Rn nas residências ficaram, na sua maioria, abaixo de 100 Bq/m3, com apenas um caso onde a concentração ficou entre 200 e 400 Bq/m3. Com relação aos postos de trabalho, todas as medidas de concentração de 222Rn ficaram abaixo de 100 Bq/m3. As concentrações de 222 Rn nas amostras das águas de poços foram medidas, em intervalos de cerca de quatro dias, por meio do monitor de radônio AlphaGUARD PQ2000 PRO. Os cálculos das concentrações de atividade iniciais de radônio na água foram feitos a partir da curva de decaimento do 222Rn e do equilíbrio secular entre o 222Rn e o 226Ra, observados depois de 30 dias. Os resultados indicaram que cerca de 70% dos valores das concentrações de 222Rn ficaram acima do valor recomendado pela USEPA, de 11,1 Bq/L, representando risco radiológico causado por este radionuclídeo.
Considering the growing interest of International Agencies and national Governmental organs in studies and measurements of radon activity in air, soil gas and ground water (mainly from artesian wells) as well as scarceness of such measurements at Brazilian territory, present studies were initiated by the Laboratory of Applied Nuclear Physics of Federal University of Technology – Paraná (UTFPR) in collaboration with the Institute of Radiation Protection and Dosimetry (IRD) and the Center of Nuclear Technology Development (CDTN) of Brazilian Commission on Nuclear Energy (CNEN). This Collaboration started in 2003. Radon monitoring program is based mainly on use of Solid State Nuclear Track Detectors for radon activity measurements in air. Continuous electronic radon detectors are used for radon measurements in soil gas and water. Current work presents the results of indoor 222Rn activity of dwellings and working places of Curitiba-PR and radon concentration in ground water samples from artesian wells from aquifers of the same area. The indoor measurements of radon activity were performed using Solid State Nuclear Track Detectors CR-39. After the exposition, CR-39 detectors were submitted to chemical development which permitted to make alpha particle tracks counting. The results of calibration of CR-39 together with efficiency of used exhalation chambers as well as alpha particle tracks chemical development procedure were erformed in cooperation with CDTN and collaboration with the National Institute of Radiological Sciences (NIRS). The major part of indoor 222Rn concentration in residences was found below 100 Bq/m3. In the case of working places, all measurements present 222Rn concentration bellow 100 Bq/m3. The studies of radon activity in water were performed using the samples of water from artesian wells submitted to recursive measurements by instant radon detector AlphaGUARD PQ2000 PRO during few weeks with intervals of about 4 days between each measurement approximately. The calculations of initial radon activity in water were done considering the 222Rn decay correction as well as equilibrium level of 222Rn and 226Ra observed after 30 days of measurements. Obtained results show that about 70% measured activity levels of 222Rn are higher than recommended value of 11.1 Bq/L which represent the risk for the human health associated with this radionuclide.
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OLIVEIRA, JOSELENE de. "Determinacao dos niveis de radioatividade natural em aguas utilizadas para abastecimento publico no Estado de Sao Paulo .Vol. 2." reponame:Repositório Institucional do IPEN, 1998. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10699.
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Narloch, Danielle Cristine. "Medidas de concentração de radônio proveniente de argamassas de cimento portland, gesso e fosfogesso." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1711.
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CAPESO cimento Portland é bastante empregado na construção civil e apresenta em sua composição o gesso natural. Para minimizar custos é possível substituir parte do gesso desta composição pelo fosfogesso. O fosfogesso é um resíduo gerado a partir da produção dos fertilizantes e é constituído, essencialmente, por cálcio dihidratado e algumas impurezas, como fluoretos, metais em geral e radionuclídeos. Atualmente, toneladas de fosfogesso são armazenadas à céu aberto próximo das indústrias de fertilizantes, causando a contaminação do meio ambiente. O elemento 226Ra, presente nesses materiais, ao passar pela série de decaimento radioativo, transforma-se em gás 222Rn. Esse gás, ao ser inalado pode decair dentro dos pulmões e neste caso, os seus produtos depositam-se nas paredes pulmonares ocasionando exposição à radiação, podendo ser um potencial causador de câncer pulmonar. Dessa forma, o objetivo desta pesquisa foi medir os níveis de concentração de 222Rn em corpos de prova de argamassa de cimento Portland, de gesso e de fosfogesso provenientes do Estado do Paraná, além de caracterizar o material e estimar a concentração de radônio em um ambiente de convívio humano hipotético construído com paredes destes materiais. Para as medidas de atividade do 222Rn foi utilizado o monitor AlphaGUARD (Saphymo GmbH). A análise qualitativa e quantitativa foi realizada por meio da espectrometria gama e da EDXRF com tubos de alvos de Au e Ag (AMPTEK), e com alvo de Mo (ARTAX) e os ensaios mecânicos com equipamento de raios X (Gilardoni) e com a prensa mecânica (EMIC). Os valores médios da atividade do radônio no ar obtidos pelo estudo dos materiais armazenados no recipiente foram de 854 ± 23 Bq/m3, 60,0 ± 7,2 Bq/m3 e 52,9 ± 5,4 Bq/m3 para argamassas de cimento Portland, de gesso e de fosfogesso, respectivamente. Estes resultados extrapolados para o ambiente hipotético de 36 m3 com paredes revestidas com os materiais foram de 3366 ± 91 Bq/m3, 237 ± 28 Bq/m3 e 208 ± 21 Bq/m3 para argamassas de cimento Portland, gesso e fosfogesso. Considerando o limite de 300 Bq/m3 estabelecido pela ICRP, observa-se que, para o revestimento de cimento Portland a exposição não é segura e requer alguns procedimentos de mitigação específicos. A partir da espectrometria gama foi calculado o valor do rádio equivalente (Raeq) para as argamassas de cimento Portland, gesso e fosfogesso que resultou em 78,2 ± 0,9 Bq/kg; 58,2 ± 0,9 Bq/kg e 68,2 ± 0,9 Bq/kg, respectivamente. Os valores do Raeq das amostras encontram-se inferiores ao limite máximo de 370 Bq/kg. Em relação a análise qualitativa e quantitativa das amostras por EDXRF, os resultados permitiram identificar e quantificar os elementos que compõe as amostras como o Ca, S, Fe, entre outros.
Portland cement being very common construction material has in its composition the natural gypsum. To decrease the costs of manufacturing, the cement industry is substituting the gypsum in its composition by small quantities of phosphogypsum, which is the residue generated by the production of fertilizers and consists essentially of calcium dihydrate and some impurities, such as fluoride, metals in general, and radionuclides. Currently, tons of phosphogypsum are stored in the open air near the fertilizer industries, causing contamination of the environment. The 226 Ra present in these materials, when undergoes radioactive decay, produces the 222Rn gas. This radioactive gas, when inhaled together with its decay products deposited in the lungs, produces the exposure to radiation and can be a potential cause of lung cancer. Thus, the objective of this study was to measure the concentration levels of 222Rn from cylindrical samples of Portland cement, gypsum and phosphogypsum mortar from the state of Paraná, as well as characterizer the material and estimate the radon concentration in an environment of hypothetical dwelling with walls covered by such materials. Experimental setup of 222Rn activity measurements was based on AlphaGUARD detector (Saphymo GmbH). The qualitative and quantitative analysis was performed by gamma spectrometry and EDXRF with Au and Ag targets tubes (AMPTEK), and Mo target (ARTAX) and mechanical testing with x- ray equipment (Gilardoni) and the mechanical press (EMIC). Obtained average values of radon activity from studied materials in the air of containers were of 854 ± 23 Bq/m3, 60,0 ± 7,2 Bq/m3 e 52,9 ± 5,4 Bq/m3 for Portland cement, gypsum and phosphogypsum mortar, respectively. These results extrapolated into the volume of hypothetical dwelling of 36 m3 with the walls covered by such materials were of 3366 ± 91 Bq/m3, 237 ± 28 Bq/m3 e 208 ± 21 Bq/m3for Portland cement, gypsum and phosphogypsum mortar, respectively. Considering the limit of 300 Bq/m3 established by the ICRP, it could be concluded that the use of Portland cement plaster in dwellings is not secure and requires some specific mitigation procedure. Using the results of gamma spectrometry there were calculated the values of radium equivalent activity concentrations (Raeq) for Portland cement, gypsum and phosphogypsum mortar, which were obtained equal to 78,2 ± 0,9 Bq/kg; 58,2 ± 0,9 Bq/kg e 68,2 ± 0,9 Bq/kg, respectively. All values of radium equivalent activity concentrations for studied samples are below the maximum level of 370 Bq/kg. The qualitative and quantitative analysis of EDXRF spectra obtained with studied mortar samples allowed to evaluate quantitate and the elements that constitute the material such as Ca, S, Fe, and others.
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OLIVEIRA, JOSELENE de. "Determinacao dos niveis de radioatividade natural em aguas utilizadas para abastecimento publico no Estado de Sao Paulo .Vol 1." reponame:Repositório Institucional do IPEN, 1998. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10698.
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David, Anne. "Influence des paramètres hydroclimatologiques sur les déplacements verticaux du radon-222 en zone non-saturée." Paris 6, 1992. http://www.theses.fr/1992PA066109.
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La prospection des anomalies de radon-222 dans les gaz du sol a pour but de recherche les sites favorables a l'implantation de forage d'eau en milieu fissure. L'etude classique de la variabilite spatiale du gaz est maintenant consideree comme insuffisante, au regard des fluctuations temporelles non negligeables mises en evidence dans la litterature et au cours de nos investigations: il s'avere que certaines perturbations atmospheriques influencent sensiblement l'equilibre de la masse gazeuse du sol. Un suivi des concentrations rn dans les gaz du sol a ete entrepris pendant un mois sur une parcelle experimentale de 1818 m, en vingt points prospectes chacun a 15, 30, 55 et 115 cm de profondeur. Les resultats montrent l'existence notable de fluctuations diurnes (20-30%) et journalieres (40%) a la profondeur standard (55 cm) d'echantillonnage, correlees principalement au gradient de pression atmospherique. Un modele numerique monodimensionnel a ete developpe aux differences finies pour simuler en transitoire le role effectif de la pression barometrique sur les concentrations rn d'un milieu poreux materialisant la zone non-saturee. Des processus dynamiques simples, consistant a engendrer des vitesses de darcy a partir des variations de pression atmospherique, et a les integrer sous le terme advectif dans l'equation classique du transport du radon, ont ete appliques au milieu. En supposant que le radon se deplace avec l'air dans le milieu poreux, il convient de considerer deux porosites differentes pour que le callage des donnees experimentales soit concluant; en d'autres termes, le radon semble profiter, sur notre site, d'une porosite nettement plus faible que l'air lors de son deplacement. Le modele a ete utilise pour apporter les corrections temporelles aux concentrations rn mesurees lors d'une prospection
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Bhatia, Rachit. "Revolution in Autonomous Orbital Navigation (RAON)." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7676.
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Spacecraft navigation is a critical component of any space mission. Space navigation uses on-board sensors and other techniques to determine the spacecraft’s current position and velocity, with permissible accuracy. It also provides requisite information to navigate to a desired position, while following the desired trajectory. Developments in technology have resulted in new techniques of space navigation. However, inertial navigation systems have consistently been the bedrock for space navigation.
Recently, the successful space mission GOCE used on-board gravity gradiometer for mapping Earth’s gravitational field. This has motivated the development of new techniques like cold atom accelerometers, to create ultra-sensitive gravity gradiometers, specifically suited for space applications, including autonomous orbital navigation.
This research aims to highlight the existing developments in the field of gravity gradiometry and its potential space navigation applications. The study aims to use the Linear Covariance Theory to determine specific sensor requirements to enable autonomous space navigation for different flight regimes.
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Sadiq, Kamran. "On the range of the Attenuated Radon Transform in strictly convex sets." Doctoral diss., University of Central Florida, 2014. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6349.
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In the present dissertation, we characterize the range of the attenuated Radon transform of zero, one, and two tensor fields, supported in strictly convex set. The approach is based on a Hilbert transform associated with A-analytic functions of A. Bukhgeim.
We first present new necessary and sufficient conditions for a function to be in the range of the attenuated Radon transform of a sufficiently smooth function supported in the convex set. The approach is based on an explicit Hilbert transform associated with traces of the boundary of A-analytic functions in the sense of A. Bukhgeim. We then uses the range characterization of the Radon transform of functions to characterize the range of the attenuated Radon transform of vector fields as they appear in the medical diagnostic techniques of Doppler tomography. As an application we determine necessary and sufficient conditions for the Doppler and X-ray data to be mistaken for each other.
We also characterize the range of real symmetric second order tensor field using the range characterization of the Radon transform of zero tensor field.Ph.D.
Doctorate
Mathematics
Sciences
Mathematics
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Otto, Andreas [Verfasser], Günter [Akademischer Betreuer] Radons, Günter [Gutachter] Radons, and Karl Heinz [Gutachter] Hoffmann. "Frequency domain methods for the analysis of time delay systems / Andreas Otto ; Gutachter: Günter Radons, Karl Heinz Hoffmann ; Betreuer: Günter Radons." Chemnitz : Universitätsbibliothek Chemnitz, 2016. http://d-nb.info/1214648630/34.
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McCulloch, John. "Experiment and continuity in the narrative fiction of Ramon Gomez de la Serna in 1920s Spain." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370083.
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Aubert, Pierre. "Calcul haute performance pour la détection de rayon Gamma." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLV058/document.
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La nouvelle génération d'expériences de physique produira une quantité de données sans précédent. Cette augmentation du flux de données cause des bouleversements techniques à tous les niveaux, comme le stockage des données, leur analyse, leur dissémination et leur préservation.Le projet CTA sera le plus grand observatoire d'astronomie gamma au sol à partir de 2021. Il produira plusieurs centaines de Péta-octets de données jusqu'en 2030 qui devront être analysées, stockée, compressées, et réanalysées tous les ans.Ce travail montre comment optimiser de telles analyses de physique avec les techniques de l'informatique hautes performances par le biais d'un générateur de format de données efficace, d'optimisation bas niveau de l'utilisation du pipeline CPU et de la vectorisation des algorithmes existants, un algorithme de compression rapide d'entiers et finalement une nouvelle analyse de données basée sur une méthode de comparaison d'image optimiséeThe new generation research experiments will introduce huge data surge to a continuously increasing data production by current experiments. This increasing data rate causes upheavals at many levels, such as data storage, analysis, diffusion and conservation.The CTA project will become the utmost observatory of gamma astronomy on the ground from 2021. It will generate hundreds Peta-Bytes of data by 2030 and will have to be stored, compressed and analyzed each year.This work address the problems of data analysis optimization using high performance computing techniques via an efficient data format generator, very low level programming to optimize the CPU pipeline and vectorization of existing algorithms, introduces a fast compression algorithm for integers and finally exposes a new analysis algorithm based on efficient pictures comparison
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Nguyen, Phuoc Tai. "Trace au bord de solutions d'équations de Hamilton-Jacobi elliptiques et trace initiale de solutions d'équations de la chaleur avec absorption sur-linéaire." Phd thesis, Université François Rabelais - Tours, 2012. http://tel.archives-ouvertes.fr/tel-00710410.
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Cette thèse est constituée de trois parties. Dans la première partie, on s'intéresse au problème de trace au bord d'une solution positive de l'équation de Hamilton-Jacobi (E1) $-\Delta u+g(|\nabla u|)=0$ dans un domaine borné $\Omega$ de ${\mathbb R}^N$, satisfaisant (E2) $u = \mu$ sur $\partial \Omega$. Si $g(r) \geq r^q$ avec $q > 1$, on prouve que toute solution positive de (E1) admet une trace au bord considérée comme une mesure de Borel régulière, pas nécessairement localement bornée. Si $g(r) = r^q$ avec $1 < q < q_c = \frac{N+1}{N}$ , on montre l'existence d'une solution positive dont la trace au bord est une mesure de Borel régulière $\nu \not \equiv \infty$ et on caractérise les singularités frontières isolées de solutions positives. Si $g(r) = r^q$ avec $q_c \leq q < 2$, on établit une condition nécessaire de résolution en terme de capacité de Bessel $C_{\frac{2-q}{q},q'} . On étudie aussi des ensembles éliminables au bord pour des solutions modérées. La deuxième partie est consacrée à étudier la limite, lorsque $k \to \infty$, de solutions d'équation $\partial_t u - \Delta u + f(u) =0$ dans ${\mathbb R}^N \times (0;\infty)$ avec donnée initiale $k\delta_0$ où $0$ est la masse de Dirac concentrée à l'origine et f est une fonction positive, continue, croissante et satisfaisant $f(0) = f^{-1}(0) = 0$. On prouve, sous certaines hypothèses portant sur f, qu'il existe essentiellement trois types de comportement possible en fonction des valeurs finies ou infinies des intégrales $\int_1^\infty f^{-1}(s)ds$ et $\int_1^\infty F^{-1/2}(s)ds$, où $F(s)=\int_0^s f(r)dr$. Grâce à ces résultats, on donne une nouvelle construction de la trace initiale et quelques résultats d'unicité et de non-unicité de solutions dont la donnée initiale n'est pas bornée. Dans la troisième partie, on élargit le cadre de nos investigations et généralise les résultats obtenus dans la deuxième partie au cas où l'opérateur est non-linéaire. En particulier, on s'intéresse à des propriétés qualitatives de solutions positives de l'équation $ \partial_t u-\Delta_p u+f(u)=0$ où $p > 1, \Delta_p u = div(\abs{\nabla u}^{p-2}\nabla u)$ et $f$ est une fonction continue, croissante, positive et satisfaisant $f(0) = 0 = f^{-1}(0)$. Si $p > \frac{2N}{N+1}$, on fournit une condition suffisante portant sur f pour l'existence et l'unicité des solutions fondamentales de données initiales $k\delta_0$ et on étudie la limite, lorsque $k \to \infty$, qui dépend du fait que $f^{-1}$ et $F^{-1/p}$ soient intégrables à l'infini ou pas, où $F(s) =\int_0^s f(r)dr. On donne aussi de nouveaux résultats de non-unicité de solutions avec donnée initiale non bornée. Si $p \geq 2$, on prouve que toute solution positive admet une trace initiale dans la classe de mesures de Borel régulières positives. Finalement on applique les résultats ci-dessus au cas modèle $f(u)=u^\alpha \ln^\beta(u+1)$ avec $\alpha>0$ et $\beta>0$.
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Higueret, Stéphane. "Développement d’un dosimètre électronique compact à base de capteurs CMOS pour la mesure du radon." Université Louis Pasteur (Strasbourg) (1971-2008), 2007. https://publication-theses.unistra.fr/public/theses_doctorat/2007/HIGUERET_Stephane_2007.pdf.
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L’exposition du public au gaz radon 222Rn fait l’objet d’une attention croissante. Les méthodes traditionnelles de détection de radon étant soit peu flexibles, soit très chères, cette thèse présente le développement d’un dispositif électronique compact et autonome qui s’appuie sur les progrès récents en microélectronique pour la physique des particules. Le coeur du dispositif est un circuit intégré CMOS original (basse tension, faible consommation) qui assure à la fois les fonctions de capteur et de traitement. Les premiers tests, d’efficacité et en sources de particules alpha, s’appuient sur des simulations détaillées (TRIM, GEANT IV). Différents prototypes de cartes électroniques ont été développés pour d’une part la détection passive de radon à différentes concentrations et d’autre part la détection supplémentaire des descendants sur aérosols 218Po et 214Po qui contribuent de façon importante à l’irradiation α interne". Le système final est une carte miniaturisée au format CB, qui comprend quatre circuits pour la détection simultanée de radon et de ses descendants solides. Une excellente linéarité a été obtenue jusqu’à 80 kBq. M-3 sur le banc de test BACCARA au Laboratoire de Mesure des Aérosols de l‘IRSN à Saclay. Un circuit de deuxième génération est également proposéRadon detection is a long-standing challenge in the field of radioprotection, and the IPHC Institute of Strasbourg has pushed for the development of a fully electronic device, portable and really standalone. Our first prototype of CMOS system-on-chip is presented, together with efficiency tests and the corresponding physics simulations (TRIM, GEANT IV). We describe several electronic boards which have been developed for various kinds of tests, firstly passive detection of -particles from gaseous 222Rn in a large spectrum of activity concentrations. In a second stage, active collection of the daughter isotopes 218Po and 214Po was performed: these elements, appearing as attached on the aerosols present in air, are an important contribution to internal -irradiation. The final electronic system, of only 10 cm size, includes four independent chips to ensure simultaneous detection of radon gas and its aerosols. An excellent linearity has been measured up to 80 kBq. M-3 on the BACCARA bench of the IRSN at Saclay. A new generation chip is also studied
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Kummrow, Fabio. "Blue rayon como alternativa para extração de compostos orgânicos genotóxicos presentes em amostras de águas." Universidade de São Paulo, 2001. http://www.teses.usp.br/teses/disponiveis/9/9137/tde-09082017-145026/.
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A combinação do teste de Ames e métodos seletivos de extração para os principais grupos de compostos responsáveis pela atividade genotóxica em amostras ambientais tem sido muito utilizada. O objetivo foi validar o uso do Blue rayon como alternativa para extração de compostos presentes em águas brutas e tratadas. Foram realizados experimentos comparativos entre o Blue rayon e XAD-4 com amostras fortificadas e amostras reais. Dois mananciais, um contaminado com compostos policíclicos e outro não, foram estudados. As amostras foram extraídas com resina XAD4, e com Blue rayon, este último seletivo para compostos policíclicos. Os extratos foram testados com as linhagens de Salmonella typhimurium TA98 e TA100 na presença e ausência de mistura S9. O Blue rayon foi menos eficiente na detecção da mutagenicidade total das amostras quando comparado com a XAD-4. Porém foi capaz de distinguir a mutagenicidade já presente na água bruta daquela gerada durante o tratamento.The combination of the Ames test and selective extraction methodologies has been successfully used to indicate the possible classes of organic contaminants in environmental samples. The aim of this study was to validate the use of Blue rayon as an alternative extraction method to detect compounds in raw and treated waters. Two different water bodies were evaluated and in one of the sites, raw waters were known to be contaminated with polycyclic compounds. Experiments comparing the Blue rayon technique with XAD-4 resin were done in environmental and spiked samples. The extracts were tested for mutagenicity with Salmonella typhimurium strains TA98 and TA100, with and without metabolic activation. Blue rayon was less efficient in detecting the overall mutagenicity of the samples analyzed in comparison with XAD-4. It was able though to distinguish the mutagenicity due to the contaminants in raw from the ones generated by water treatment.
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Bin, Radin Nasirudin Radin Adi Aizudin [Verfasser], Ernst J. [Akademischer Betreuer] Rummeny, Sibylle [Akademischer Betreuer] Ziegler, and Franz [Akademischer Betreuer] Pfeiffer. "Analysis of multi-energy spectral CT for advanced clinical, pre-clinical, and industrial applications / Radin Adi Aizudin Bin Radin Nasirudin. Gutachter: Sibylle Ziegler ; Franz Pfeiffer. Betreuer: Ernst J. Rummeny." München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1069986151/34.
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Hurst, Stephanie. "Radium- und Radon-Isotopen-Untersuchungen als Hilfsmittel für die Aquiferdiagnose unter besonderer Berücksichtigung der geochemischen und hydrochemischen Verhältnisse im Grundwasserleiter." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-163988.
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Zielsetzung der Arbeit war vorrangig die Entwicklung bzw. Weiterentwicklung von Methoden zur verbesserten Interpretation der hydraulischen Gegebenheiten in einem Grundwasserleiter mit Hilfe der Bestimmung von Radiumisotopenverhältnissen im Verlauf von Pumpversuchen. Daneben wurden 222Rn/226Ra-Verhältnisse betrachtet und interpretiert. Des Weiteren wurden Gesteinsuntersuchungen durchgeführt sowie Untersuchungen an Gesteinsoberflächen (Sekundärminerale) um Aussagen über das Löslichkeitsverhalten bzw. die Mobilität von Radium im Grundwasser zu erhalten. Die Grundwasser- und Gesteinsproben stammten vor allem aus dem Umfeld der kontinentalen Tiefbohrung (KTB Oberpfalz) sowie aus der Vorbohrung zur KTB, aber auch aus benachbarten Bundesländern und der Tschechischen Republik (Egergraben). Im Ergebnis zeigte sich, dass sich die Untersuchung der Isotopenverhältnisse zur vertiefenden Aquiferdiagnose gut eignet. Die geochemischen Untersuchungen erlaubten einen Einblick in das Löslichkeitsverhalten der untersuchten Radionuklide.
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Radin, Ivan [Verfasser], Gerhard [Akademischer Betreuer] Rödel, and Daniel [Akademischer Betreuer] González. "Functional analysis of the putative mitochondrial copper chaperone AtCox11 / Ivan Radin. Gutachter: Gerhard Rödel ; Daniel Gonzalez. Betreuer: Gerhard Rödel." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://d-nb.info/1069096474/34.
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Hanegan, Brian Scott. "A Performer's Analysis and Improvisational Guide to Jazz Sonata for Soprano Saxophone and Piano (1994), by Ramon Ricker (b. 1943)." Diss., North Dakota State University, 2017. https://hdl.handle.net/10365/26668.
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In the twentieth century, saxophonists are encountering compositions in the repertoire that contain musical elements from both the classical and the jazz idioms. As a result, saxophonists need more technical and improvisational skills to perform these works. Ramon Ricker?s (b. 1943) Jazz Sonata for Soprano Saxophone and Piano (1994) is an example from this repertoire that draws on both of these traditions. This disquisition presents a comprehensive performer?s analysis and improvisational guide to each of the three movements of Ricker?s Jazz Sonata. In chapters 2, 4, and 6, the analysis chapters, I discuss the specific technically challenging elements within each movement. These elements pertain to altered scales, articulations, accents, and polychord harmonies in the first movement (chapter 2); to tuning, interpretation of the melody, subtone, rapid note passages, and swing style in the second movement (chapter 4); and to pitch, technical passages, accents, syncopated melodies, and interpretation of the melody in the third movement (chapter 6). In addition, musical examples and performance suggestions are provided to elaborate on these specific areas of focus. In chapters 3, 5, and 7, the improvisational guide chapters, I address two improvisational techniques for each chapter that can be used in the solo sections of each movement. These improvisational techniques refer to pentatonic patterns and intervallic or triadpair patterns in the first movement (chapter 3); to the ii?V?I harmonic progression and rhythmicbased method of improvisation in the second movement (chapter 5); and to altered dominant chords and quartal patterns in the third movement (chapter 7). In addition, I have composed a solo for each movement using the two jazz concepts addressed in each chapter. I consulted recent literature by jazz scholars and performers to provide a new perspective on how to develop both the technical prowess and the jazz conceptual prowess needed to perform Ricker?s sonata. This study has also been informed by two interviews I conducted with the composer about this piece. This disquisition is intended as a guide for saxophonists to help them create their own improvised solos in Ricker?s sonata, and, by extension, in other jazzinfluenced works in the saxophone repertoire.
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Ford, Wesley. "The Advancement of Stable, Efficient and Parallel Acceleration Methods for the Neutron Transport Equation." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLX105/document.
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Dans cet article, nous proposons une nouvelle bibliothèque de techniques non linéaires pour accélérer l’équation de transport en ordonnées discrètes. Deux nouveaux types de méthodes d'accélération non linéaire appelées méthode de rééquilibrage spatialement variable (SVRM) et accélération de matrice de réponse (RMA), respectivement, sont proposées et étudiées. La première méthode, SVRM, est basée sur le calcul de la variation spatiale de premier ordre de l'équation de la balance des neutrons. RMA, est une méthode DP0 qui utilise la connaissance de l'opérateur de transport pour former une relation cohérente. Deux variantes distinctes de RMA, appelées respectivement Explicit-RMA (E-RMA) et Balance (B-RMA), sont dérivées. Les propriétés de convergence des deux méthodes d'accélération sont étudiées pour deux schémas d'itération différents de l'opérateur de transport de la méthode des caractéristiques (MOC) pour une dalle 1D, en utilisant une analyse spectrale et une analyse de Fourier. Sur la base des résultats de la comparaison 1D, seuls les outils RMA et CMFD ont été implémentés dans la bibliothèque. Les performances de RMA sont comparées à celles de CMFD en utilisant les tests 3D C5G7, ZPPR et UH12. Les schémas de résolution parallèles et séquentiels sont considérés. L'analyse des résultats indique que les deux variantes de RMA ont une efficacité et une stabilité améliorées par rapport au CMFD, pour les matériaux à diffusion optique. De plus, le RMA montre une amélioration importante de la stabilité et de l'efficacité lorsque la géométrie est décomposée spatialement. Pour obtenir des performances numériques optimales, une combinaison de RMA et de CMFD est suggérée. Une enquête plus approfondie sur l'utilisation et l'amélioration de la RMA est proposée. De plus, de nombreuses idées pour étendre les fonctionnalités de la bibliothèque sont présentéesIn this paper we propose a new library of non-linear techniques for accelerating the discrete-ordinates transport equation. Two new types of nonlinear acceleration methods called Spatially Variant Rebalancing Method (SVRM) and Response Matrix Acceleration (RMA), respectively, are proposed and investigated. The first method, SVRM, is based on the computation of the zeroth and first order spatial variation of the neutron balance equation. RMA, is a DP0 method that uses knowledge of the transport operator to form a consistent relationship. Two distinct variants of RMA, called Explicit-RMA (E-RMA) and Balance (B-RMA), respectively, are derived. The convergence properties of both acceleration methods are investigated for two different iteration schemes of the method of characteristics (MOC) transport operator for a 1D slab, using spectral and Fourier analysis. Based off the results of the 1D comparison, only RMA and CMFD were implemented in the library. The performance of RMA is compared to CMFD using the C5G7, ZPPR, and UH12 3D benchmarks. Both parallel and sequential solving schemes are considered. Analysis of the results indicates that both variants of RMA have improved effectiveness and stability relative to CMFD, for optically diffusive materials. Moreover, RMA shows great improvement in stability and effectiveness when the geometry is spatially decomposed. To achieve optimal numerical performance, a combination of RMA and CMFD is suggested. Further investigation into the use and improvement of RMA is proposed. As well, many ideas for extending the features of the library are presented
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Ahumada, Bustamante Guido. "Analyse harmonique sur l'espace des chemins d'un arbre." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37611090m.
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Andersson, Emmy, and Darko Draskovic. "Dreaming of Beating the Market : A Fundamental Analysis Study on the Stockholm Stock Exchange." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-155705.
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The aim of this paper is to test and further improve fundamental analysis models developed by Piotroski (2000) and Rados and Lovric (2009). The improvement seeks to reverse the information in the previous models by taking relative importance and strength of both positive and negative fundamental signals into consideration. The theoretical framework used includes the efficient market hypothesis, fundamental analysis and investing in high book-to-market companies. The Piotroski model, two Rados’s and Lovric’s models and two variations of our model were tested on a portfolio consisting of high book-to-market companies from the Stockholm Stock Exchange during the period 1999-2008. The results show that our EDA Model was the most successful at identifying short selling candidates, as EDA Low portfolio rendered market adjusted returns of -19% on average. Moreover, our EDC model was the best performing at identifying buy-and-hold candidates, with an average annual market adjusted return of 31,5%. The success of our models implies that the market is not using the information captured by them fully and in a timely manner.
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Ansari, Homa [Verfasser], Richard [Akademischer Betreuer] Bamler, Richard [Gutachter] Bamler, Ramon F. [Gutachter] Hanssen, and Michael [Gutachter] Eineder. "Efficient High-Precision Time Series Analysis for Synthetic Aperture Radar Interferometry / Homa Ansari ; Gutachter: Richard Bamler, Ramon F. Hanssen, Michael Eineder ; Betreuer: Richard Bamler." München : Universitätsbibliothek der TU München, 2018. http://d-nb.info/1179360710/34.
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Viennot, Guillaume. "Utilisation de techniques d'imagerie de synthèse pour le calcul de la propagation des champs électromagnétiques." Limoges, 2012. http://aurore.unilim.fr/theses/nxfile/default/20c5b13d-dddf-4016-b0ac-fcb56fddb6d3/blobholder:0/2012LIMO4038.pdf.
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Dans ce mémoire de thèse nous présentons une adaptation des algorithmes de synthèse d’image réaliste afin de réaliser des calculs de propagation électromagnétique. Après avoir présenté les fondements des principales méthodes de calculs numériques des deux domaines, nous avons cherché un moyen d’utiliser les méthodes stochastiques de lancer de rayons. Celui-ci repose sur l’utilisation du théorème d’induction et de la théorie des images afin de calculer les courants équivalents sur les surfaces. Le fonctionnement général d’un moteur de rendu est explicité ainsi que l’ensemble des adaptions qui lui ont été apportées. Ensuite les résultats de deux implémentations différentes sont exposés et comparés à une méthode de calcul classique. La première implémentation est basée sur l’utilisation de particules d’amplitude de probabilité. La seconde implémentation est basée directement sur l’utilisation de particules de champs. Cette étude souligne également l’importance des fonctions de répartitions des variables aléatoires sur les résultats. Les différentes pistes dégagées sont ensuite évoquéesIn this thesis report we are presenting an adaptation of realistic image synthesis algorithms to perform calculations of electromagnetic wave propagation. After presenting the basis of the main methods of numerical calculations in the two domains, we find a way to use stochastic ray tracing for wave propagation. This is based on using the induction theorem and image theory to calculate the equivalent currents on the surfaces. The overall functioning of a rendering engine is explained and all the adaptations that were made. Then the results of two different implementations are presented and compared to a conventional method of calculation. The first implementation is based on amplitude of probability particles. The second implementation is based directly on field particles. This study also highlights the importance of the probability density functions on results. The possible evolutions are then presented
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Aydin, Ümit [Verfasser], Jens [Akademischer Betreuer] Haueisen, Ceon [Akademischer Betreuer] Ramon, and Carsten H. [Akademischer Betreuer] Wolters. "Combined EEG and MEG source analysis of epileptiform activity using calibrated realistic finite element head models / Ümit Aydin. Gutachter: Ceon Ramon ; Carsten H. Wolters. Betreuer: Jens Haueisen." Ilmenau : Universitätsbibliothek Ilmenau, 2015. http://d-nb.info/1072072939/34.
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Aydin, Ümit [Verfasser], Jens [Akademischer Betreuer] Haueisen, Ceon Akademischer Betreuer] Ramon, and Carsten H. [Akademischer Betreuer] [Wolters. "Combined EEG and MEG source analysis of epileptiform activity using calibrated realistic finite element head models / Ümit Aydin. Gutachter: Ceon Ramon ; Carsten H. Wolters. Betreuer: Jens Haueisen." Ilmenau : Universitätsbibliothek Ilmenau, 2015. http://nbn-resolving.de/urn:nbn:de:gbv:ilm1-2015000040.
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Brunk, Fiona. "Intersection problems in combinatorics." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/765.
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Fraysse, Joël. "Etude des facteurs de variation de la composition chimique du lait des troupeaux de brebis laitières dans le Rayon de Roquefort et les Pyrénées Atlantiques." Toulouse, INPT, 1996. http://www.theses.fr/1996INPT011A.
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Pour les troupeaux ovins laitiers, il n'existe pas de controle systematique de la composition chimique du lait de chaque brebis traite sur l'ensemble de la lactation. L'etude des facteurs non genetiques de variation de la composition chimique du lait necessite d'analyser la production laitiere au niveau du troupeau. En effet, les seules donnees systematiques de composition chimique sont etablies dans le cadre du paiement du lait a sa qualite, au moyen d'analyses decadaires realisees dans chaque troupeau. La methode d'analyse presentee exploite ces informations provenant des laiteries, conjointement a des informations provenant des fichiers du controle laitier officiel. Ces dernieres permettent de reconstituer l'inventaire quotidien des brebis traites dans chaque troupeau, avec une marge d'erreur acceptable. La description de ces inventaires quotidiens permet de definir la notion de structure du troupeau, caracterisant l'effectif des brebis traites, conditionnee par les flux d'entree a la traite et de sortie des femelles. Ces flux sont susceptibles de modifier l'avancement du stade moyen de lactation des brebis traites dans chaque troupeau. Ainsi, a l'echelle du troupeau, la notion de structure permet de tenir compte de l'effet du stade de lactation, principal facteur individuel de variation de la composition chimique du lait de brebis. Un modele d'analyse de la production laitiere du troupeau a ete defini par analogie au modele d'analyse des performances des brebis, utilise pour l'evaluation genetique. Il tient compte du niveau genetique moyen du troupeau, de facteurs de structure du troupeau et de facteurs specifiques (annee, utilisation d'ensilage) et permet d'en mesurer les effets respectifs. Parallelement, des simulations de structures de troupeau ont ete menees pour aider a l'interpretation des analyses de donnees reelles
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Gurevsky, Evgeny. "Conception de lignes de fabrication sous incertitudes : analyse de sensibilité et approche robuste." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2011. http://tel.archives-ouvertes.fr/tel-00820619.
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Les travaux présentés dans cette thèse portent sur la conception de systèmes de fabrication en contexte incertain. La conception d'un tel système peut être vue comme un problème d'optimisation qui consiste à trouver une configuration qui permet d'optimiser certains objectifs tout en respectant des contraintes technologiques et économiques connues. Les systèmes de fabrication étudiés dans ce mémoire sont des lignes d'assemblage et d'usinage. La première est une ligne qui se présente comme une chaîne de postes de travail où, dans chaque poste, les opérations d'assemblage s'exécutent de manière séquentielle. La deuxième, quant à elle, est une ligne particulière qui se compose de machines de transfert comportant plusieurs boîtiers multibroches où les opérations s'exécutent simultanément. Dans un premier temps, nous décrivons de différentes approches permettant de modéliser l'incertitude des données en optimisation. Une attention particulière est portée sur les deux approches suivantes : l'approche robuste et l'analyse de sensibilité. Puis, nous présentons trois applications : la conception d'une ligne d'assemblage et d'une ligne d'usinage soumises aux variations de temps opératoires et la conception d'une ligne d'assemblage avec les temps opératoires connus sous la forme d'intervalles des valeurs possibles. Pour chaque application, nous identifions les performances attendues ainsi que la complexité de la prise en compte de l'incertitude. Ensuite, nous proposons de nouveaux critères d'optimisation en adéquation avec la problématique introduite. Enfin des méthodes de résolution sont développées pour appréhender les différents problèmes mis en évidence par ces critères.