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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.
371

Axiological Investigations

Olson, Jonas January 2005 (has links)
<p>The subject of this thesis is <i>formal axiology</i>, i.e., the discipline that deals with structural and conceptual questions about value. The main focus is on <i>intrinsic</i> or <i>final</i> value. The thesis consists of an introduction and six free-standing essays. The purpose of the introduction is to give a general background to the discussions in the essays. The introduction is divided into five sections. Section 1 outlines the subject matter and sketches the methodological framework. Section 2 discusses the supervenience of value, and how my use of that notion squares with the broader methodological framework. Section 3 defends the concept of intrinsic or final value. Section 4 discusses issues in value typology; particularly how intrinsic value relates to final value. Section 5 summarises the essays and provides some specific backgrounds to their respective themes.</p><p>The six essays are thematically divided into four categories: The first two deal with specific issues concerning analyses of value. Essay 1 is a comparative discussion of competing approaches in this area. Essay 2 discusses, and proposes a solution to, a significant problem for the so called ‘buck-passing’ analysis of value. Essay 3 discusses the ontological nature of the bearers of final value, and defends the view that they are particularised properties, or <i>tropes</i>. Essay 4 defends <i>conditionalism</i> about final value, i.e., the idea that final value may vary according to context. The last two essays focus on some implications of the formal axiological discussion for normative theory: Essay 5 discusses the charge that the buck-passing analysis prematurely resolves the debate between consequentialism and deontology; essay 6 suggests that conditionalism makes possible a reconciliation between consequentialism and moral particularism. </p>
372

Reconstruction des électrons et recherche de couplages anormaux dans le canal pp->ZZ->4l avec le détecteur CMS auprès du LHC

Sabes, David 19 October 2012 (has links) (PDF)
La thèse en physique des particules que j'ai effectuée au sein de l'équipe CMS (Compact Muon Solenoid) du Laboratoire Leprince-Ringuet de l'École Polytechnique porte sur l'analyse de la production de di-bosons pp→ZZ+X et la recherche de couplages anormaux et ce, dans le cadre de l'expérience CMS et des données accumulées à l'aide du grand collisionneur de hadrons du CERN, le LHC. Elle débute avec le démarrage du LHC en fin 2009 et l'étude et l'optimisation de la reconstruction des électrons via la combinaison de deux algorithmes afin d'améliorer les performances à bas moment transverse. Les critères de sélection des événements caractéristiques des désintégrations de bosons Z, assurant une sélection pure d'électrons, ont été étudiés. Les efficacités de reconstruction des électrons pour les données 2010 et 2011 ainsi que leurs erreurs statistiques et systématiques ont été mesurées et ces mesures ont ensuite été utilisées par la collaboration CMS pour les analyses 2010 et 2011. Une étude des caractéristiques des radiations dans l'état final (Final State Radiation) affectant les leptons issus de la désintégration du Z a été menée. Un algorithme en vue de récupérer les photons FSR et reconstruire pleinement la masse du Z a été développé et optimisé. Il corrige 4.2% des cas ZZ→4μ tout en assurant une pureté de sélection des photons FSR de 95.6%. L'analyse physique développée dans cette thèse porte sur la recherche et l'extraction de limites sur les couplages trilinéaires neutres. L'existence de ces couplages est interdite dans le formalisme du Modèle Standard mais peut cependant être introduite dans un Lagrangien effectif par l'ajout de deux termes de couplages f4Z et f5Z dans le cas du couplage ZZZ, en vue de la recherche d'une nouvelle physique. La présence de ces couplages anormaux se traduit généralement par une augmentation de la section efficace de production des di-bosons ZZ ainsi que par les déformations des distributions cinématiques des Z ou encore de la masse des 4 leptons par rapport à l'attendu Modèle Standard. Dans le cadre de l'analyse du canal pp→ZZ→4l, une sélection pure des événements a été établie et les distributions différentielles du moment transverse et de la rapidité des bosons Z sont également présentées. Une recherche des couplages anormaux est effectuée en utilisant une méthode de repondération des distributions simulées et des limites sont extraites par la technique CLs. Les limites obtenues avec un niveau de confiance de 95% sont: -0.0116< f4Z <0.0116 et -0.0119< f5Z <0.0119.
373

Late Effects After Autologous Bone Marrow Transplantation in Childhood

Frisk, Per January 2003 (has links)
Fifty children with hematologic malignancies have been treated with autologous BMT in Uppsala. The aim was to describe late effects in this group with special reference to cataracts, reduced final height, and to hepatic, renal, and pulmonary late effects. Cataracts: All patients who received TBI in their conditioning developed posterior subcapsular cataract after BMT. A few patients with visual impairment affecting daily life needed cataract surgery, whereas the visual acuity was well preserved in most of the other patients. Final height: There was a decrease in final height relative both to height at BMT and to target height. This decrease was significant both in those who had received TBI only and in those who had been given cranial irradiation. Cranial irradiation, young age at BMT, and short duration of GH treatment were predictors of height loss. Hepatic function: Hepatic function was well preserved over a period of 10 years after BMT. TBI did not appear to be a risk factor for hepatic impairment. Renal function: Six months after BMT there was a decrease in renal function in patients who had received TBI. It then recovered, albeit incompletely, and stabilized. After the first year there was little change over a period of 10 years after BMT. TBI appeared to be the most important risk factor for the development of chronic renal impairment in a number of patients. Nephrotoxic antibiotics may have contributed. Pulmonary function: Six months after BMT there was a decrease in pulmonary function in those who received TBI. It then recovered and stabilized at the pretransplant level. After the first year there was little change over a period of 10 years after BMT. TBI appeared to be the most important risk factor for restrictive pulmonary disease in a number of patients whereas chemotherapy might also have been of importance for impaired gas exchange.
374

Axiological Investigations

Olson, Jonas January 2005 (has links)
The subject of this thesis is formal axiology, i.e., the discipline that deals with structural and conceptual questions about value. The main focus is on intrinsic or final value. The thesis consists of an introduction and six free-standing essays. The purpose of the introduction is to give a general background to the discussions in the essays. The introduction is divided into five sections. Section 1 outlines the subject matter and sketches the methodological framework. Section 2 discusses the supervenience of value, and how my use of that notion squares with the broader methodological framework. Section 3 defends the concept of intrinsic or final value. Section 4 discusses issues in value typology; particularly how intrinsic value relates to final value. Section 5 summarises the essays and provides some specific backgrounds to their respective themes. The six essays are thematically divided into four categories: The first two deal with specific issues concerning analyses of value. Essay 1 is a comparative discussion of competing approaches in this area. Essay 2 discusses, and proposes a solution to, a significant problem for the so called ‘buck-passing’ analysis of value. Essay 3 discusses the ontological nature of the bearers of final value, and defends the view that they are particularised properties, or tropes. Essay 4 defends conditionalism about final value, i.e., the idea that final value may vary according to context. The last two essays focus on some implications of the formal axiological discussion for normative theory: Essay 5 discusses the charge that the buck-passing analysis prematurely resolves the debate between consequentialism and deontology; essay 6 suggests that conditionalism makes possible a reconciliation between consequentialism and moral particularism.
375

Arbetsrättsliga krav vid offentlig upphandling

Tingström, Lina January 2013 (has links)
Offentlig upphandling är inte endast ett sätt att tillförskaffa sig varor, utan kan också användas som ett samhällspolitiskt instrument för att verka för sociala mål som ställts upp. Hur de varor och tjänster som upphandlas produceras inverkar på de arbetsrättsliga och sociala förhållandena i leverantörskedjan, och genom att ställa sociala krav vid en offentlig upphandling kan den upphandlande myndigheten förstärka förtroendet hos invånarna. Trots en omfattande EU-rättslig reglering på området är det idag dock osäkert vilka möjligheter den upphandlande myndigheten ges att ställa arbetsrättsliga krav på leverantören av upphandlingsföremålet. Syftet med uppsatsen är att utreda i vilken omfattning en upphandlande myndighet kan ställa arbetsrättsliga krav vid en offentlig upphandling, samt utreda om förslaget till nytt klassiskt upphandlingsdirektiv kommer innebära några förändringar för den upphandlande myndigheten vad gäller möjligheten att ställa arbetsrättsliga krav.  Av uppsatsen framkommer att det inte finns någon klar gräns vilka arbetsrättsliga krav den upphandlande myndigheten får ställa på leverantören vid en offentlig upphandling. Den största möjligheten att ställa ett arbetsrättsligt krav torde föreligga om kravet ställs såsom ett tilldelningskriterium, då EU-domstolen har klargjort att sociala krav får ställas för att tillgodose behov hos personer samt att ett tilldelningskriterium inte behöver vara kopplat till upphandlingsföremålet, utan det kan vara kopplat till hur en vara eller tjänst produceras. Förändringarna i förslaget till nytt klassiskt upphandlingsdirektiv innebär inte att möjligheterna att ställa arbetsrättsliga krav vid en offentlig upphandling ökar, dock ges den upphandlande myndigheten genom förslaget mer stöd i valet av vilka arbetsrättsliga krav som är tillåtna att ställa. / Public procurement is not only a method to acquire goods, but can also be used as a sociopolitical device to gain social visions. The method that supplied goods and services are produced by affect the labor and social conditions in the supply chain. By acquiring social conditions in a public procurement the procuring authority may strengthen the reliance of the citizens. Despite a comprehensive EU legislation in the area, it is uncertain which labor requirements the procuring authority may impose the supplier. The purpose of this thesis is to investigate to what extent a procuring authority may impose labor requirements in a public procurement, and to investigate if the proposal to a new procurement directive will result in an opportunity to impose labor requirements on the supplier. This thesis has concluded that it is not clear what labor requirements the procuring authority may demand the supplier of a public procurement. The biggest opportunity to demand a labor requirement to a supplier is by using award criteria. The Court of Justice of the European Union have clarified that social requirements may be used to meet needs of individuals and that award criteria do not need to be connected to the object of the procurement, but can be connected to the production of the goods or services of the contract. The thesis has also shown that the changes in the proposal to a new procurement directive do not increase the possibilities to require labor requirements in a public procurement. However, it does give the procuring authority further support in the choice of which labor requirements it may require.
376

Pratiques funéraires du Bronze final IIIb au premier âge du Fer en Languedoc occidental et Midi-Pyrénées : approche archéo-anthropologique des nécropoles à incinération.

Lenorzer, Sandrine 14 April 2006 (has links) (PDF)
Les populations du Bronze final IIIb au premier âge du Fer (vers 900-475 avant J.-C.) en Languedoc occidental et Midi-Pyrénées, sont essentiellement connues par l'intermédiaire de leurs nécropoles. La crémation des défunts constitue une pratique quasi-exclusive pour toute la zone chrono-culturelle, ce qui limite grandement la caractérisation biologique de ces populations. Nous nous sommes fondée sur un corpus de plus de 2000 tombes secondaires à incinération essentiellement issues de onze nécropoles majeures de la période, qui ont été analysées à travers différents paramètres : modes de dépôt des restes osseux, modalités de recrutement à l'échelle de la nécropole, poids total d'ossements déposés dans la sépulture, indices pondéraux des différentes régions anatomiques et données sur l'aspect des ossements. Les résultats de ce premier niveau d'analyse ont ensuite été replacés dans les contextes chrono-culturels de chaque nécropole. Une évolution chronologique des gestes funéraires notamment en ce qui concerne le mode de dépôt des restes osseux et la quantité d'ossements placés dans la tombe a pu être mise en évidence. Cependant des particularités très locales, parfois à l'échelle d'une seule nécropole et donc vraisemblablement d'une communauté, semblent également se détacher. Un essai d'interprétation de l'évolution de la structuration sociale des populations vivantes et des modalités de recrutement des défunts est aussi proposée. Parallèlement, l'étude anthropologique personnelle de près de 400 amas osseux nous a permis de fonder une réflexion méthodologique sur le traitement des ossements incinérés en dépôt secondaire. Cette démarche a pour objectif d'optimiser la quantité et la qualité des observations, en minimisant le temps imparti à l'analyse.
377

LES ENCEINTES PRE- ET PROTOHISTORIQUES DE CORSE - ESSAI DE COMPARAISON AVEC QUELQUES SITES DE TOSCANE

Mazet, Sylvain 27 October 2006 (has links) (PDF)
Dès le Vème millénaire, la présence d'enceintes est attestée en Méditerranée occidentale. Destinée à ceinturer un espace dont la fonction a<br />pu changer entre le Néolithique moyen et l'Age du Fer, l'enceinte peut être un fossé, une levée de terre, une palissade ou un mur en pierre<br />sèche, comme c'est le cas en Corse. Cette recherche s'intéresse, de ce fait, à l'évolution des techniques constructives de ces structures en pierre<br />sèche. Des datations provenant de fouilles effectuées sur certains gisements ont permis d'élaborer une typo-chronologie, fournissant des<br />indices quant à l'occupation de sites se caractérisant par la seule présence d'enceintes. Afin d'appliquer la méthodologie de l'étude des<br />structures corses à celles de Toscane, le cadre géographique de notre recherche a été étendu à toute l'aire corso-toscane. La faible<br />représentation de ce type de structures dans la littérature archéologique de la Toscane a été confirmée par quelques campagnes de<br />prospection ciblées, notamment dans la vallée de l'Ombrone. Néanmoins quelques gisements ceinturés ont été inventoriés dans l'archipel<br />toscan. Dans le nord de la Corse, il semblerait que les enceintes enserrant l'habitat au Néolithique évolué et au Néolithique final, soient<br />issues de l'utilisation de techniques constructives développées localement. En revanche, à l'Age du Bronze, la proche Sardaigne pourrait<br />avoir diffusé la façon de construire des murs employant des blocs volumineux aux faces planes, utilisée dans le sud de la Corse pour ériger<br />des structures ceinturant, entre autres, des centres de transformation des produits alimentaires. L'utilisation d'outils en bronze, lors de<br />l'extraction et du débitage de la roche, expliquerait les différences entre les techniques constructives employées au Néolithique et à l'Age du<br />Bronze.
378

Implementation of match-making portal

Javar, Shima, Rafique, Faisal January 2009 (has links)
<p>In this project-collaboration between Växjö University and Sideum company- a matchmakingportal is designed. This portal’s purpose is to ease the communication betweenVäxjö university’s students who are interested in doing their final thesis/project in anenvironment outside the university and companies which have some appropriatethesis/projects for these students and would like their projects to be done by them.There are different kinds of users that have different roles on this portal. The majorusers are students and companies which take the most advantage of this website.Once a student registers her name and completes her profile, she will receive emailscontaining information about uploaded projects on the portal by companies, which aresuitable according to what she already has mentioned in her profile. She can also searchherself to find her desired project as soon as companies upload their projects on the portal.On the other hand companies can search to find students who meet their requirements.Administrators of the portal are able to do match-making between students andcompanies. They access to every part of the portal and have right to edit, delete, change,upload, making reports and supervise the system.Other groups are guests of system. Guests are users of the system who are not registeredyet, they will not receive any email about uploaded thesis/projects on the portal but theycan search for them, themselves.</p>
379

Comparing Approximations for Risk Measures Related to Sums of Correlated Lognormal Random Variables

Karniychuk, Maryna 09 January 2007 (has links) (PDF)
In this thesis the performances of different approximations are compared for a standard actuarial and financial problem: the estimation of quantiles and conditional tail expectations of the final value of a series of discrete cash flows. To calculate the risk measures such as quantiles and Conditional Tail Expectations, one needs the distribution function of the final wealth. The final value of a series of discrete payments in the considered model is the sum of dependent lognormal random variables. Unfortunately, its distribution function cannot be determined analytically. Thus usually one has to use time-consuming Monte Carlo simulations. Computational time still remains a serious drawback of Monte Carlo simulations, thus several analytical techniques for approximating the distribution function of final wealth are proposed in the frame of this thesis. These are the widely used moment-matching approximations and innovative comonotonic approximations. Moment-matching methods approximate the unknown distribution function by a given one in such a way that some characteristics (in the present case the first two moments) coincide. The ideas of two well-known approximations are described briefly. Analytical formulas for valuing quantiles and Conditional Tail Expectations are derived for both approximations. Recently, a large group of scientists from Catholic University Leuven in Belgium has derived comonotonic upper and comonotonic lower bounds for sums of dependent lognormal random variables. These bounds are bounds in the terms of "convex order". In order to provide the theoretical background for comonotonic approximations several fundamental ordering concepts such as stochastic dominance, stop-loss and convex order and some important relations between them are introduced. The last two concepts are closely related. Both stochastic orders express which of two random variables is the "less dangerous/more attractive" one. The central idea of comonotonic upper bound approximation is to replace the original sum, presenting final wealth, by a new sum, for which the components have the same marginal distributions as the components in the original sum, but with "more dangerous/less attractive" dependence structure. The upper bound, or saying mathematically, convex largest sum is obtained when the components of the sum are the components of comonotonic random vector. Therefore, fundamental concepts of comonotonicity theory which are important for the derivation of convex bounds are introduced. The most wide-spread examples of comonotonicity which emerge in financial context are described. In addition to the upper bound a lower bound can be derived as well. This provides one with a measure of the reliability of the upper bound. The lower bound approach is based on the technique of conditioning. It is obtained by applying Jensen's inequality for conditional expectations to the original sum of dependent random variables. Two slightly different version of conditioning random variable are considered in the context of this thesis. They give rise to two different approaches which are referred to as comonotonic lower bound and comonotonic "maximal variance" lower bound approaches. Special attention is given to the class of distortion risk measures. It is shown that the quantile risk measure as well as Conditional Tail Expectation (under some additional conditions) belong to this class. It is proved that both risk measures being under consideration are additive for a sum of comonotonic random variables, i.e. quantile and Conditional Tail Expectation for a comonotonic upper and lower bounds can easily be obtained by summing the corresponding risk measures of the marginals involved. A special subclass of distortion risk measures which is referred to as class of concave distortion risk measures is also under consideration. It is shown that quantile risk measure is not a concave distortion risk measure while Conditional Tail Expectation (under some additional conditions) is a concave distortion risk measure. A theoretical justification for the fact that "concave" Conditional Tail Expectation preserves convex order relation between random variables is given. It is shown that this property does not necessarily hold for the quantile risk measure, as it is not a concave risk measure. Finally, the accuracy and efficiency of two moment-matching, comonotonic upper bound, comonotonic lower bound and "maximal variance" lower bound approximations are examined for a wide range of parameters by comparing with the results obtained by Monte Carlo simulation. It is justified by numerical results that, generally, in the current situation lower bound approach outperforms other methods. Moreover, the preservation of convex order relation between the convex bounds for the final wealth by Conditional Tail Expectation is demonstrated by numerical results. It is justified numerically that this property does not necessarily hold true for the quantile.
380

High quality, high performance rendering using shadow ray acceleration and aggressive micropolygon tessellation rates

Djeu, Peter 15 June 2011 (has links)
Rendering in computer graphics is the process of converting a three dimensional scene description into a two dimensional image. In this work we focus on high quality rendering, which has numerous applications in entertainment and visualization. Many films today are created either entirely or in concert with computationally generated imagery and serve as a vivid example of the benefits of high quality rendering. This dissertation consists of two parts, each presenting novel work in the field of high quality, high performance rendering. The first part proposes the use of volumetric occluders, or a collection of axis-aligned boxes placed within a polygonal model, to accelerate the rendering of shadows cast by the model while producing images identical to the unaccelerated baseline. We show that our approach performs well on single object scenes and extend our approach for use with scenes from a professional open source movie. Although the technique has not yet proven itself on these multi-object scenes, we identify the scene characteristics which are hampering the approach and show that in some cases it is still possible to achieve an improvement in performance. The second part of the dissertation presents a new way to determine micropolygon tessellation rate within a Reyes style renderer. Our new scheme, called final approach tessellation, evaluates the tessellation rate close to a Reyes surface rather than upon entry into its bounding box. Our determination of the tessellation rate is more aggressive than previous approaches, producing a more compact tessellation which in turn is faster to compute and requires less memory. Our evaluation shows that although final approach tessellation is promising in theory, it ultimately fails to improve performance on actual test scenes. / text

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