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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.
241

La monnaie en droit : nature d'une abstraction outre fondée : essai dialectique et logique sur la dualité dans la catégoricité juridique et sur l'abstraction d'hérédité monétaire

Leclerc, Normand 11 1900 (has links)
"Thèse présentée à la Faculté des études supérieures en vue de l'obtention du grade de Docteur en droit (LL.D.)" / Cette suite d'essais analyse la conception de la monnaie en droit, cherchant à isoler l'originalité de sa nature abstraite. La tradition juridique caractérise la monnaie à la fois comme un fait et comme un droit parce qu'elle présuppose un sens substantif au nom commun 'monnaie', étant ainsi incapable d'admettre que la monnaie, par sa place unique dans les catégories du droit, est le mécanisme qui suppose l'avenir indéterminé en y enchâssant le présent. La difficulté de la monnaie est que, comme catégorie, elle n'est pas incluse aux catégories usuelles de droit privé. Son caractère abstrait l'empêche d'ailleurs d'être incluse parmi les objets qui ont une extension. La monnaie se définit plutôt par négation relativement aux catégories usuelles. Elle est donc reconnaissable entre toutes. Dans la relation sujet-objet, la monnaie versée n'est évidemment pas un sujet. Dans son sens strict, la monnaie réfère aujourd'hui au papier-monnaie. Il est vrai que ce dernier existe matériellement puisqu'il est tangible. Mais paradoxalement, en tant qu'objet, la monnaie est ni une somme, ni une obligation en nature, ni un bien, ni une représentation de dette, ni une mesure, ni consomptible, ni fongible au sens pertinent de ces mots. Comment saisir la substance d'une notion qui se soustrait aux catégories usuelles de la doctrine? Voilà la difficulté fondamentale de la thèse. Répétons son mode original de définition: la monnaie n'est pas identique à une somme due, mais - en étant payée - elle en éteint une; conversement, la somme due n'est pas identique à la monnaie perçue, mais -lorsque payée en trop - cette dernière est déclarée indue et sujette à répétition (l'indu devient dû). La définition de la monnaie procède par 'corécurrence' : elle définit quelque chose d'indéterminé puisqu'un membre de la définition réfère à l'autre et viceversa. Sa nature s'exprime par sa fonction dans la structure des prestations. Mais la doctrine la traite d'abord comme une somme due, sans distinguer outre mesure ce type de dette des autres prestations. Or, à titre d'exécution d'une obligation, une somme d'argent non seulement éteint d'autant les montants, dus à une époque ou l'autre, mais, puisque ces derniers sont appariés aux obligations en nature en tant que prix dû en contrepartie des prestations caractérisées à être effectuées, la perception des sommes d'argent conduit encore à la mobilité des biens parmi les personnes. D'où le paradoxe: une somme d'argent est destinée à circuler précisément pour être la fin des sommes dues. La doctrine enseigne la thèse unitaire du paiement des obligations (en son acception large du droit civil) : sont mis dans un même sac les faits exécutés pour satisfaire à des obligations en nature et les paiements de sommes d'argent dues. Or, elles sont en premier dues, puis payées. Ils sont dits former un ensemble. Ce sac est le temps lui-même. Il s'agit d'une interprétation de l'univers des prestations, précisément une interprétation de la notion d'univers où l'actualité homogène d'un ensemble exclut de faire une place à l'éventualité de valeurs futures par contraste aux valeurs passées. Pour réduire la notion d'univers à celle d'ensemble actuel, l'astuce est de fermer la dualité 'ensemble/membre' en substituant au membre l'ensemble: l'un des objets inclus à l'ensemble doit être à la fois un élément existant de l'ensemble et la collection de tous ses éléments, constituant ainsi la jonction substantive sous-jacente à cette dualité. IV Cet objet fondateur est d'habitude nommé le zéro de l'ensemble. Traitant ainsi l'ensemble des exécutions des obligations, il doit y avoir un élément qui ait à la fois la nature d'une promesse et celle d'un fait. Cet élément est la monnaie. Ainsi, la monnaie a une nature double, à la fois concept et référent du concept. La somme due est exécutée en monnaie et, conversement, la monnaie est la somme transférée à titre de paiement: substituant une définition dans l'autre, l'exécution de la somme due est la somme transférée, une formule conduisant à la régression infinie. Qui donc est le débiteur de cette somme transférée depuis aussi longtemps que la monnaie a circulé et circulera? La difficulté conceptuelle de la monnaie est de comprendre cette métamorphose, où l'exécution d'un fait en satisfaction d'une obligation se révèle elle même être une promesse. Pourquoi alors distinguer une obligation et son exécution? La monnaie cumule la nature catégorique d'une chose matérielle délivrée - autrefois l'or, aujourd'hui le papier-monnaie - et la nature d'une somme due; cette façon de penser mène à réifier les dettes, à leur conférer une existence matérielle. Mais devoir l'argent est fondamentalement la durée du terme d'une relation entre deux personnes. Et payer la monnaie est l'extinction de ce terme. Alors paradoxalement, l'exprimant dans une dualité catégorique, la monnaie a une durée et en même temps n'en a pas. Cette postulation d'une union des termes opposés d'une dualité n'est pas sans précédent. Pour aider le lecteur à s'en rendre compte, je documente que le thème de la migration de la valeur pécuniaire des choses par la médiation de la monnaie dans le paiement des sommes dues rappelle celui de la métempsycose (migration de l'âme) utilisée pour conceptualiser le fondement de la Couronne médiévale, le don de Dieu qui sacrait la continuité des règnes successifs d'une lignée héréditaire de régents. À cette époque, on conceptualisait la continuité historique d'un peuple par les deux corps du roi; sa nature cumulait à la fois celle d'un individu et celle de l'ensemble des individus soumis à son règne. Unique entre tous, on considérait que l'un des individus était un ensemble d'un. Cette attitude platonique était crue nécessaire en droit public pour résoudre la difficulté conceptuelle de la continuité historique d'une communauté en dépit de la nature temporelle de ses membres; elle recevait son écho en droit privé. La thèse unitaire du paiement d'obligations - où, tout comme en économique, la capacité de permutation de biens est elle-même considérée être un bien ordinaire - semble reposer sur cette même conception d'une nécessaire nature double. Dans l'univers des prestations, selon la doctrine, un ensemble infini de valeurs successives formées sur une période de temps indéfinie est considéré être fondé sur un objet transcendant qui cumule les faces opposées d'une dualité: à la fois somme (d'argent) et chose, à la fois droit et fait accompli en exécution d'une obligation, à la fois fait et valeur future. Ce paradigme traditionnel est indifférent à la dualité des prestations: non pécuniaire et pécuniaire. TI y arrive en substantivant la non-existence d'une somme. L'explication proposée ici en est une de structure. L'univers des prestations serait plutôt une dichotomie de deux dualités distinctes: 10 une dualité catégorique, celle de l'exécution de prestations particulières - où avoir fait quelque chose et ne pas l'avoir fait sont des action et abstention caractérisées, et 20 une dualité modale (circulaire), devoir un montant libellé en iv-a devise ou (exclusivement) ne pas le devoir, l'avoir payé ou non. L'obligation de livrer une prestation caractérisée à quelqu'un est appariée à la somme d'argent due par ce dernier en contrepartie de cela; on alterne d'une obligation non pécuniaire à la promesse de payer un montant d'argent sans que quiconque puisse cumuler le beurre et l'argent du beurre à un instant donné. Mais encore, une somme due en suit une autre au travers de la monnaie, cette dernière étant toujours le revers de la somme due. Il n'est pas nécessaire de dire que la monnaie existe, ni de dire qu'elle n'existe pas; il suffit de dire qu'elle éteint la somme due. Non seulement la somme due - versée (renversée) en monnaie - est éteinte, mais encore par le nominalisme elle peut toujours acquitter de nouveau une somme d'autant; il suffit qu'un créancier accepte qu'on la lui doive plutôt que de s'en remettre au troc de choses existantes. Cette nouvelle perspective du paiement des obligations distingue deux types de raisonnements. La vérification catégorique rétrospective d'une exécution en nature survenue se démarque de la modalité où la conséquence juridique de l'extinction d'une somme due se retourne en la possibilité a priori de réitérer cette conséquence encore contre une somme pouvant pourtant n'être pas encore déterminée. La possibilité d'une continuité historique n'a pas la nature finie d'un fait. L'objet qu'est la monnaie déborde de la notion ordinaire d'objet puisqu'il est circulaire: la 'monnaie' est "éteindre une somme (due) puis (est encore) monnaie". Dans la lignée héréditaire des sommes, constituées pour être éteintes, éteintes pour être constituées, la monnaie est ni le prédécesseur, ni un successeur particulier; elle est la fonction qui ouvre continuellement l'éventualité d'autres successeurs. La monnaie est une abstraction et sa nature unique est confirmée au Canada depuis 1967. Une fois la convertibilité du papier-monnaie abandonnée, la monnaie n'est plus une promesse de payer: la banque centrale n'est plus tenue de délivrer l'or à la demande du porteur, ni d'échanger le billet de banque en billets du Dominion. Le papiermonnaie est, depuis, trivialement remplacé seulement par du papier-monnaie. Enfin, l'abstraction monétaire donne à la banque centrale une personnalité morale inédite. Si la Couronne est créancière des uns et débitrice aux autres, alors en contraste la banque centrale qui n'est pas une banque - est ni créancière, ni débitrice du papier-monnaie. La problématique de l'inclusion de la monnaie dans les catégories traditionnelles du droit a une solution inédite. La monnaie s'offre en complément des concepts du discours juridique. L'encaissement d'une somme due emporte comme conséquence la fin de son terme, mais encore il en appelle à nouveau une autre, éventuellement. Ainsi, la monnaie est le bain de renouvellement des sommes. Sa qualification ni ... ni... louvoie entre les deux termes en les niant alternativement. / This series of essays analyses the concept of money in the law, seeking to isolate its unique and highly abstract nature. Traditionallaw teaching characterizes money both as a fact and as a right premised as it is on the idea that common nouns like 'money' must have substantive meaning; it is thereby unable to accept that money, by virtue of its unique place amongst the categories of private law, is the mechanism supposing the indeterminate future by embedding the present into it. The difficulty with money is that, as a category, it is not included amongst the usual categories ofprivate law. Its abstract character prevents it from being included amongst objects that have extension. Rather money is defined by negation with respect to the usuallegal categories. It is thereby uniquely recognizable. In the subject-object relationship, paid money is obviously not a subject. In its strict meaning, money refers today to paper-money. It is true that the latter does exist physically because it is tangible. But paradoxicalIy, as an object, money is neither a sum owed, nor an obligation in kind, nor a good, nor representing a debt, nor a measurement, nor consumable, nor fungible in the relevant sense ofthose terms. How does one capture the substance of a notion that defies the usual categories of legal discourse? That is the fundamental difficulty of the thesis. The entirely unique way of defining money bears repeating: Cash money is not identical to a sum owed but extinguishes one as it is being paid; conversely, a sum owed is not identical with money received, since when money is paid without obligation, the sum can be recovered as undue (the undue becomes due). The definition ofmoney proceeds by 'corecurrence': it defines something indeterminate, in that one definition refers to the other and vice versa. Its nature stems from its function in the structure of prestations. But the legal scholarship treats it principally as a sum owed, without further distinguishing this type of debt from other prestations. Now, as the performance of an obligation, a sum ofmoney not only as much pays off any amount, due at one time or another, but, because those are paired to obligations in kind as the price owed in consideration ofparticular performances to be accomplished; the cashing of sums of money still conducts the movement of goods among persons. Whence a paradox: A sum of money is destined to circulate precise1y to extinguish sums (due). Legal scholarship generally teaches the thesis of unity of performance of obligations (payment in its broad civillaw meaning): AlI acts accomplished in the performance of obligations in kind and all payments of sums of money are put in the same bag. Now, they are first owed, then received. These operations are said to form a single set. This bag is time itself. 1t is an interpretation of the universe of prestations, more precise1y an interpretation of the notion of universe where the homogeneous actuality of a set excludes to give place to the possibility of future values by contrast to past values. To close the notion of a universe to that of an actual vi set, the trick is to close the duality 'set/member' by replacing the member by the set: one of the objects included in the set must be at once an existing element of the set and be the collection of aIl its elements, constituting thereby the substantive junction underlying this duality. This foundational object is usually called the zero of the set. In the set of performances of obligations (prestations) with which we are dealing here, there must similarly be an element in the nature of both a promise and a fact. That element is money. So money has a dual nature, both concept and referent of the concept. The sum owed is performed in money and, conversely, money is the sum transferred as payment: substituting one definition in the other, the performance of the sum owed is the sum transferred, a formula leading to infinite regression. Who then is the debtor of this sum transferred for as long as money did and will circulate? The conceptual difficulty with money is to understand this metamorphosis, where the performance of a fact in satisfaction of an obligation reveals itselfto be a promise. Why then bother to distinguish a promise from the performance of it? Money cumulates the categorical nature of a physical thing being delivered - in olden days gold, today paper-money - and the nature of a sum owed; this way of thinking would tend to reify debts, to confer them physical existence. Yet to owe money is fundamentally the duration of the term of a relationship between two persons. And to pay money is to put an end to this term. So paradoxically, to express it in a categorical duality, money has duration and at the same time it has none. Such a union of the polar opposites of a duality is not unprecedented. To help the reader realise this, l document how the theme of migration ofpecuniary value ofthings by means ofmoney being given in payment of amounts owed is reminiscent of metempsychosis (migration of the soul) used to conceptualise the foundation of the medieval Crown, the gift ofGod that consecrated the continuity of successive reigns of an hereditary line of regents. At that time, the historical continuity of the people was conceptualised by the King's two bodies: both that of an individual and that of the set of individuals subject to his reign. Unique amongst aIl, one foundational individual was considered to constitute a set of one. This platonic attitude was believed necessary in public law to resolve the conceptual difficulty of the historical continuity of a community despite the temporal nature of its individuals; it was put to similar use in private law with respect to money. The thesis of unity of performance of obligations - where, like in economics, the capacity to exchange goods is considered an ordinary good itself - appears to rely on the same conception of a necessary dual nature. In the universe of prestations, according to traditionallegal scholarship, an infinite set of successive values taking shape over an indefinite period of time is viewed as founded on a transcendental object which cumulates the opposite faces ofa duality: both sum (of money) and thing, both right and act accomplished in the performance of an obligation, both fact and future value. This traditional paradigm disregard the duality of prestations: pecuniary and non-pecuniary. It does so by giving a substantive value to the non vi-a existence of a sumo The explanation proposed here is one of structure. The universe of prestations is rather a dichotomy of two distinct dualities: 10 a categorieal duality, that of the performance of specifie prestations - where to have done something and not to have done it are characterised action and abstention, and 20 a modal (circular) duality: to owe an amount in currency or (exclusively) not to owe it, to have paid it or not. The obligation to deliver a particular performance to someone is paired to the sum of money owed by him in consideration of it; we altemate from nonpecuniary obligation to promises to pay an amount of money without one being able to have his cake and eat it too at any time. But still, one amount owed follow another thru money, money always being the tuming over of the sum owed. We are not obliged to state that money exists, or that it does not; it suffiees to say that it extinguishes the sum owed. Not only is the sum owed extinguished upon money being tumed (paid) in, but by virtue of nominalism it still can extinguish anew a further sum of same amount; it is sufficient that a creditor accept to be owed a sum ofmoney rather than to revert to the barter ofphysical things. This new reading of the payment of obligations draw apart two types of reasoning. The categorieal proof of a past specifie performance is different from the modality where the legal consequence of the extinction of a sum due is tumed over into the a priori possibility to still reiterate that same consequence against a sum that now may not yet be determined. The possibility of an historieal continuity does not have the finite nature of a fact. Money as an object transcends the concept of an ordinary object because it is circular: 'money' is "the end of a sum (owed) and (is still) money". In the hereditary line of sums, created to be extinguished or extinguished to be created, money is neither the predecessor nor a particular successor; it is the function of continuously opening up the possibility of further successors. Money is an abstraction and its unique character is confirmed in Canada since 1967. Once the convertibility of paper-money is dropped, money is no longer a promissory note: no longer does the central bank undertakes to exchange a bank note for gold or Dominion bonds. Paper-money is now trivially replaced only by paper-money. Finally, the abstract character ofmoney gives the central bank an most unusual status as a legal person. If the Crown is creditor of sorne persons and debtor to others, then by contrast the central bank - who is not a bank - is neither creditor, nor debtor ofpaper-money. The problem of fitting money within the traditional categories of the law does have an unexpected ending. Money presents itself as the complement of the concepts oflegal discourse. The cashing in of a sum triggers the end of its term, but still it calls one anew, eventually. So money is the bath of renewal of sums. In being characterised as neither... nor... it hops between the two terms by altematively negating them.
242

Étude du nombre de polynômes irréductibles dans les corps finis avec certaines contraintes imposées aux coefficients

Beauchamp Houde, Gabriel 08 1900 (has links)
L'objectif de ce mémoire est de dénombrer les polynômes irréductibles unitaires sur un corps fini en prescrivant des contraintes sur les coefficients. Dans les prochaines pages, il sera question de fixer simplement des coefficients, ou simplement de fixer leur signe, leur cubicité ou leur quarticité. / The objective of this thesis is to count monic irreducible polnomials over a finite field under some conditions on the coefficients of the polynomial. These conditions will be simply to fix some coefficients, or to fix their sign, cubicity or quarticity.
243

Estudo da adsorção de monocamadas de água em gipsita(010) através de óptica não linear / Water monolayer adsorption on Gypsum (010) investigated by nonlinear optics

Santos, Jaciara Cássia de Carvalho 23 August 2017 (has links)
Filmes de água cobrem a maior parte das superfícies em condições ambientes. O estudo dessas interfaces é crucial em biologia e em ciência dos materiais. No entanto, o completo entendimento da adsorção da água e de suas complexas redes de ligações de hidrogênio ainda não foi alcançado. Somente recentemente possuímos técnicas com a sensibilidade e seletividade para estudar estas superfícies até a última camada atômica. A espectroscopia por geração de soma de frequências (SFG) é uma técnica óptica não linear que fornece o espectro vibracional de moléculas em interfaces, sem contribuição do volume do material. A técnica SFG foi utilizada para estudar a estrutura interfacial das moléculas de água estrutural na face livre (010) do cristal natural gipsita (CaSO4 2H2O) e a adsorção de água na mesma à temperatura ambiente. Os espectros SFG na face livre (010), em atmosfera inerte, apresentaram um arranjo com anisotropia azimutal das moléculas de água estrutural com a presença de grupos OH ligados à superfície e grupos OH livre sem formar ligação de hidrogênio, apontando para fora da superfície. O arranjo anisotrópico das moléculas na face (010) é diferente daquele para as moléculas de água no volume do cristal. A adsorção de água foi estudada em equilíbrio com vapor de água em vários valores de umidade relativa. A água adsorvida na gipsita (010) também apresenta um arranjo anisotrópico, porém, diferentemente da água estrutural na superfície livre do cristal, esta apresenta um menor grau de ordenamento e suprime consideravelmente a presença de grupos OH livre. Os resultados experimentais são analisados em conjunto com simulações por dinâmica molecular ab initio realizadas por colaboradores. As simulações apresentaram boa concordância qualitativa e quantitativa com os resultados experimentais, permitindo fazer a atribuição dos espectros vibracionais experimentais, e fornecendo informações difíceis de se obter dos experimentos, como a distribuição orientacional das moléculas de água na interface e sua dinâmica de difusão espacial. / Water films cover most of surfaces under ambient conditions. The study of these interfaces is crucial in biology and materials science. However, a complete understanding of water adsorption and its complex hydrogen bonding networks has not yet been achieved. Only recently we have techniques with the sensitivity and selectivity to study these surfaces to the last atomic layer. Sum-frequency generation (SFG) is a non-linear optical technique that provides the vibrational spectrum of molecules at interfaces, without contribution from the bulk. This technique was used to study the interfacial structure of neat (010) face of Gypsum (CaSO4 2H2O) single crystals and water adsorption on the (010) face at room temperature. The SFG spectra for the neat Gypsum face (010), in inert atmosphere, presented azimuthally anisotropy arrangement of the structural water molecules with the presence of OH groups bound to the surface and free OH groups pointing out of the surface. The arrangement of water molecules on the face (010) is anisotropic but different from that of the water molecules in the bulk crystal. Water adsorption was studied in equilibrium with water vapor at several values of relative humidity. The adsorbed water also exhibited an anisotropic arrangement, however, unlike the structural water, it presents a lower ordering and the free OH groups are strongly suppressed. The experimental results are analyzed together with ab initio molecular dynamics simulations performed by collaborators. The simulations presented good qualitative and quantitative agreement with the experimental results, elucidating the assignment of the experimental vibrational spectra and yielding information that would be difficult to get from the experiments, such as the orientational distribution of interfacial water molecules and their spatial diffusion dynamics.
244

Estudo da adsorção de polieletrólitos e do ordenamento molecular de filmes poliméricos automontados através da óptica não-linear / Study of the polyelectrolyte adsorption and of the molecular ordering of polymeric self-assembled films trough nonlinear optics

Silva, Heurison de Sousa e 21 February 2011 (has links)
Neste trabalho, aplicamos técnicas de óptica não-linear de segunda ordem, em particular a Espectroscopia por Geração de Soma de Freqüências (SFG) e a Geração de Segundo Harmônico (SHG), para investigar a adsorção e o ordenamento molecular de filmes automontados de polieletrólitos variando-se os parâmetros que influenciam a adsorção (pH, força iônica, densidade de carga), além de investigar a estabilidade térmica e possíveis transições de fases nesses filmes multicamadas como função do pH das soluções e o do número de camadas. A espectroscopia SFG de filmes dos polieletrólitos poly(allylamine hydrochloride) (PAH) e poly(styrene sulfonate) (PSS) permitiu acompanhar a adsorção das camadas pelo monitoramento do campo elétrico na interface (substrato+filme adsorvido)/solução. As medidas de fase do sinal SFG confirmaram a supercompensação de cargas em todos os valores de pH estudados, exceto a pH 12, onde a adsorção foi possível devido a interações eletrostáticas locais. Os filmes secos mostraram grande ordenamento e homogeneidade quando a secagem era espontânea (sem a ação de jato de N2), independentemente do pH. Nestes filmes, observou-se pela primeira vez que as camadas adsorvidas podem alterar o ordenamento e a conformação das cadeias previamente adsorvidas. A espectroscopia SFG também apontou para a redução da densidade de carga e do ordenamento molecular quando a força iônica era aumentada, devido ao efeito de blindagem eletrostática. Os filmes tornaram-se mais inomogêneos e desordenados em virtude da compensação extrínseca. O efeito da força iônica foi o de reduzir a densidade de carga e assim o ordenamento molecular, mesmo se a secagem fosse espontânea. A técnica de SHG foi aplicada a filmes automontados de PAH e PS-119 para confirmar sua estabilidade térmica em função do pH e do número de camadas, além de verificar o ordenamento molecular antes e após o tratamento térmico. Os resultados mostraram que os filmes não são termicamente estáveis: o sinal é completamente destruído à temperatura de 150oC aproximadamente, ao contrário do que relata a literatura. As medidas SHG também confirmaram a isotropia dos filmes no plano das amostras, independente do pH ou do número de camadas. Comparando-se o sinal SHG antes e depois do aquecimento, comprovou-se que após o resfriamento lento, o sinal era restituído a quase o mesmo valor que antes, mostrando que o processo de desordem térmica é reversível. Entretanto, nenhuma transição de fase foi observada, pois a redução do sinal SHG foi lenta e gradual, sem nenhuma variação brusca que caracterizasse uma transição vítrea. Enfim, nossas medidas do sinal SHG em função do número de camadas também discordaram dos resultados da literatura, pois a susceptibilidade de segunda ordem não cresceu linearmente com o número de bicamadas. Isso indica que as moléculas não adsorvem com mesmo ordenamento em cada bicamada. Desse modo, podemos concluir que as técnicas SFG e SHG fornecem informação a nível microscópico que podem levar ao aprimoramento das aplicações dos filmes automontados, e que seriam difíceis de obter com técnicas tradicionais. / In this study, we have applied second-order nonlinear optical techniques, in particular Sum-Frequency Generation (SFG) and Second-Harmonic Generation (SHG), to investigate the adsorption and the molecular ordering of self-assembled polyelectrolyte films varying the parameters which are relevant to polyelectrolyte adsorption (pH, ionic strength, charge density), besides investigating the thermal stability and possible phase transistions in these multilayer films as function of pH of the solutions and of the number of layers. SFG spectroscopy of films fabricated with the polyelectrolytes PAH and PSS allowed us to monitor the adsorption of each layer by the electric field at the (substrate+adsorbed film)/solution interface. Phase-measurements of the SFG signal confirmed that charge supercompensation occurred at all pH values investigated, except at pH 12, where the adsorption was possible by local electrostatic interactions. Dry films have shown great order and homogeneity if the drying was spontaneous (without blow-drying with N2), independently of pH. In these films, it was observed for the first time that layer adsorption can modify the order and the conformation of previously adsorbed chains. SFG spectroscopy also pointed to the reduction of the charge density and of the molecular order if the ionic strength was increased, due to the electrostatic screening effect. The films were more inhomogeneous and disordered due to extrinsic charge compensation. The effect of the ionic strength was to reduce the charge density and the molecular order, even if the drying were slow (spontaneous). The SHG technique was applied to LBL films of PAH and PS-119 to confirm their thermal stability as a function of pH of the solutions and the number of layers, besides comparing the molecular order before and after the thermal treatment. The results have shown that the films are not thermally stable, with the SHG signal nearly vanished if the temperature of 150 oC is reached, in contrast of what is reported in the literature. SHG measurements have also confirmed that the films are isotropic in the plan of the samples, independent of pH or the number of layers. Comparing the SHG signal before and after heating, it was found that the SHG signal was considerably reduced at high temperatures, but after slow cooling it was recovered to almost the same value as before heating, showing that the thermal disorder is reversible. However, no phase transistion was observed, since the SHG signal reduction was slow and gradual, without any sudden change that would characterize a glass transition. At last, our SHG measurements as a function of the number of layers also disagreed with results in the literature, therefore the second order susceptibility did not grow linearly with the number of bilayers. This indicates that the molecules do not adsorb with same order in each bilayer. Therefore, we can conclude that SFG and SHG techniques provide information on the film arrangement at the microscopic level which could be difficult to get with traditional techniques and could also lead to the improvement of applications of LBL films.
245

Multi-label classification based on sum-product networks / Classificação multi-rótulo baseada em redes soma-produto

Llerena, Julissa Giuliana Villanueva 06 September 2017 (has links)
Multi-label classification consists of learning a function that is capable of mapping an object to a set of relevant labels. It has applications such as the association of genes with biological functions, semantic classification of scenes and text categorization. Traditional classification (i.e., single-label) is therefore a particular case of multi-label classification in which each object is associated with exactly one label. A successful approach to constructing classifiers is to obtain a probabilistic model of the relation between object attributes and labels. This model can then be used to classify objects, finding the most likely prediction by computing the marginal probability or the most probable explanation (MPE) of the labels given the attributes. Depending on the probabilistic models family chosen, such inferences may be intractable when the number of labels is large. Sum-Product Networks (SPN) are deep probabilistic models, that allow tractable marginal inference. Nevertheless, as with many other probabilistic models, performing MPE inference is NP- hard. Although, SPNs have already been used successfully for traditional classification tasks (i.e. single-label), there is no in-depth investigation on the use of SPNs for Multi-Label classification. In this work we investigate the use of SPNs for Multi-Label classification. We compare several algorithms for learning SPNs combined with different proposed approaches for classification. We show that SPN-based multi-label classifiers are competitive against state-of-the-art classifiers, such as Random k-Labelsets with Support Vector Machine and MPE inference on CutNets, in a collection of benchmark datasets. / A classificação Multi-Rótulo consiste em aprender uma função que seja capaz de mapear um objeto para um conjunto de rótulos relevantes. Ela possui aplicações como associação de genes com funções biológicas, classificação semântica de cenas e categorização de texto. A classificação tradicional, de rótulo único é, portanto, um caso particular da Classificação Multi-Rótulo, onde cada objeto está associado com exatamente um rótulo. Uma abordagem bem sucedida para classificação é obter um modelo probabilístico da relação entre atributos do objeto e rótulos. Esse modelo pode então ser usado para classificar objetos, encon- trando a predição mais provável por meio da probabilidade marginal ou a explicação mais provavél dos rótulos dados os atributos. Dependendo da família de modelos probabilísticos escolhidos, tais inferências podem ser intratáveis quando o número de rótulos é grande. As redes Soma-Produto (SPN, do inglês Sum Product Network) são modelos probabilísticos profundos, que permitem inferência marginal tratável. No entanto, como em muitos outros modelos probabilísticos, a inferência da explicação mais provavél é NP-difícil. Embora SPNs já tenham sido usadas com sucesso para tarefas de classificação tradicionais, não existe investigação aprofundada no uso de SPNs para classificação Multi-Rótulo. Neste trabalho, investigamos o uso de SPNs para classificação Multi-Rótulo. Comparamos vários algoritmos de aprendizado de SPNs combinados com diferentes abordagens propostos para classi- ficação. Mostramos que os classificadores Multi-Rótulos baseados em SPN são competitivos contra classificadores estado-da-arte, como Random k-Labelsets usando Máquinas de Suporte Vetorial e inferência exata da explicação mais provavél em CutNets, em uma coleção de conjuntos de dados de referência.
246

Estudo da largura de estados exóticos do Charmonium usando as regras de soma da QCD / Study of the Exotic Charmonium States Width using the QCD Sum Rules

Dias, Jorgivan Morais 22 September 2015 (has links)
Nesta tese, discutimos em detalhes a técnica das Regras de Soma da QCD (RSQCD) e suas aplicações em sistemas hadrônicos situados na região de massa do charmônio. Em particular, calculamos a massa, as constantes de decaimento e acoplamento, bem como a largura de decaimento dos estados $Y(4260)$,$Y(3940)$ e $Z_c^+(3900)$. Além disso, consideramos a existência do parceiro estranho deste último, o $Z^+_{cs}(3970)$, e calculamos sua largura de decaimento de modo a prever seu valor em futuros experimentos. Usamos modelos ditos exóticos para descrever tais estados. Para o $Y(4260)$ e o $Y(3940)$ usamos correntes de mistura charmônio - tetraquarks. Para os estados carregados usamos uma corrente de tetraquarks. Como resultado das aplicações das RSQCD nesses sistemas, obtivemos valores de massa e largura compatíveis com os valores experimentais medidos pelas colaborações BESIII, Belle, Babar e CLEO-c. Dessa forma, podemos afirmar que os modelos utilizados fornecem uma boa interpretação para esses estados. Investigamos também, aplicando técnicas de teorias efetivas, os estados carregados $Z^+_c(4025)$ e novamente o $Z_c^+(3900)$, além dos estados no setor do bottom $Z^+_b(10610)$ e $Z_b^+(10650)$. Usamos as Lagrangianas da Simetria Oculta de Calibre Local (HGS) e também as regras da Simetria de Spin do Quark Pesado (HQSS) para determinarmos as interações $D\\bar{D}^*$, $D^*\\bar{D}^*$, $B\\bar{B}^*$ e $B^*\\bar{B}^*$ via troca de mésons vetoriais pesados e devido à troca de dois píons correlacionados e não correlacionados entre si. Determinamos o potencial para cada interação e, com isso, procuramos por pólos na solução da matriz $T$ na equação de Bethe-Salpeter, cujo kernel é dado pelo potencial. Como resultado desses estudos, obtivemos para as interações no setor do charme, estados ligados cuja massa e largura estão em razoável acordo com os estados carregados $Z^+_c(4025)$ e $Z_c^+(3900)$. Para as interações no setor do bottom, obtemos um estado fracamente ligado próximo do limiar de massa $B\\bar{B}^*$ cuja largura e massa são compatíveis com a estrutura $Z_b^+(10610)$ observada pela Colaboração Belle. Obtivemos um cusp no limiar de massa $B^*\\bar{B}^*$ próximo do valor da estrutura $Z_b^ (10650)$ / In this thesis, we discuss in details the QCD Sum Rules (QCDSR) technique and its application to the study of hadronic systems situated in the charmonium mass region. In particular, we applied QCDSR to calculate hadronic properties such as the mass, the coupling contants as well as the total decay width of the $Y(4260)$, $Y(3940)$ and $Z_c^+(3900)$ charmoniumlike states. We have also predicted the decay width of the strange partner of the $Z_c^+(3900)$, called $Z_{cs}^+(3970)$, to be searched in future experiments. In order to describe these states, we used exotic models. For $Y(4260)$ and $Y(3940)$ states we used mixed charmonium-tetraquarks interpolating currents. For the charged states we used tetraquark currents. As a result of the application of QCDSR to these systems, we obtained masses and decay widths in good agreement with the experimental values measured by BESIII, Babar, and CLEO-c collaborations. Therefore, the currents we used within QCDSR approach provide a good interpretation for these states. Furthermore, applying effective field theories techniques, we also investigated the charged states $Z_c^+(4025)$ and $Z_c^+(3900)$, in addition to $Z^+_b(10610)$ and $Z_b^+(10650)$ in the bottom sector. Specifically, we used hidden local symmetry Lagrangians (HGS) together with heavy quark spin symmetry rules (HQSS) in order to study the interactions $D\\bar{D}^*$, $D^*\\bar{D}^*$, $B\\bar{B}^*$ and $B^*\\bar{B}^*$ by means of the heavy vector exchange and also from the exchange of two pions, interacting and noninteracting among themselves. We obtained the potencial for each interaction, then we used them as a kernel of the Bethe-Salpeter equation in order to look for poles in the $T$-matrix. Our aim was to relate these poles with the charmoniumlike states of interest. As a result, in the charm sector, we obtained bound states whoses masses and widths are in a good agreement with the charged states we have studied. With respect to the bottom sector, we have found a loosely bound state very close to the $B\\bar{B}^*$ threshold with mass and width compatible with the structure $Z_b(10610)$ observed by Belle colaboration. We have obtained a cusp in the $B^*\\bar{B}^*$ threshold very close to the mass of the $Z_b^+(10650)$ state.
247

Espectroscopia vibracional de filmes automontados de polieletrólitos através da geração de soma de frequências / Vibrational spectroscopy of self-assembled polyelectrolytes films by sum-frequency generation

Silva, Heurison de Sousa e 14 February 2007 (has links)
Neste trabalho foi utilizada Espectroscopia Vibracional por Geração de Soma de Freqüências, uma técnica óptica não-linear que é sensível à conformação molecular em interfaces e superfícies, para caracterizar o ordenamento molecular de filmes poliméricos automontados de polieletrólitos durante todos os passos do processo de fabricação, tendo como modelo o par de polieletrólitos PAH (poli(cloreto de alilamina)) / PSS (poli(estireno sulfonato de sódio)). Os espectros SFG permitiram verificar que durante o mergulho (in situ) do substrato na solução de polieletrólitos, estes adsorvem, mas se encontram numa configuração desordenada. Observou-se também que a secagem dos filmes pela ação de jato de nitrogênio produz filmes menos homogêneos do que por secagem espontânea, e às vezes até destruindo completamente o ordenamento molecular. Além disso, verificou-se também que camadas de polieletrólitos adsorvidas influenciam o ordenamento das camadas previamente adsorvidas. Com base nos resultados, modelos para a representação das estruturas desses filmes de polieletrólitos in situ e ex situ foram propostos. / In this work, Sum-Frequency Vibrational Spectroscopy, a nonlinear optical technique that is sensitive to molecular conformation at interfaces and surfaces, was used to characterize the molecular ordering of self-assembled films during all steps of self-assembly, having as model poly(allylamine hydrochloride) (PAH) / poly(styrene sulfonate) (PSS) polyelectrolyte assemble. SFG spectra showed that during immersion (in situ) of substrate in polyelectrolytes solutions, adsorption occurs but the molecules are in a disordered configuration. It was observed that the films drying by nitrogen flow are more inhomogeneous than those dried by spontaneous water evaporation. In some cases, dried films by nitrogen flow are quite disordered. Furthermore, it was observed that polyelectrolytes layers affect the ordering of the previously adsorbed layers. Based on our results, models were proposed to represent the structure of polyelectrolytes films in both: in situ and ex situ.
248

Barganha e justi?a criminal negocial : an?lise das tend?ncias de expans?o dos espa?os de consenso no processo penal brasileiro

Vasconcellos, Vinicius Gomes de 10 November 2014 (has links)
Made available in DSpace on 2015-04-14T14:48:26Z (GMT). No. of bitstreams: 1 462996.pdf: 576369 bytes, checksum: 32b2960268c15e7b5e43332bcc8b7497 (MD5) Previous issue date: 2014-11-10 / Involved in the concentration area Criminal System and Violence and in the research line Contemporary Criminal Systems, this paper aims to develop a critical analysis of the trends of expanding consensual opportunities in the Brazilian criminal justice, primarily within the introduction of negotiation mechanisms, such as plea bargaining, which, in broad terms, allows the early imposition of the punitive power in the basis of a guilty plea, in exchange of a benefit, a reduction in the punishment. As seen, it represents a strong inclination on the international criminal procedure scene, which is progressively more guided by the goal of procedural acceleration, which actually is going beyond that claim and is leading to justify the imposition of criminal sanctions with no attention to the due process of law rules. After the introductory definition of the guidelines ideas of opportunity and consensus, the main features of plea bargain will be drawn-up, fundamentally from the United States example. Then it will ask the adherence of such mechanisms to the fundaments of criminal procedural systems, besides suggesting some relevant aspects of the international scene in order to demonstrate the extend of the studied trends. On the other hand, considering the current Brazilian scenario, the consensus possibilities, which are allowed within the Juizados Especiais Criminais (Brazilian minor courts) and by the whistleblower award, will be studied. Subsequently we will analyze the legislative proposals currently under discussion at the Brazilian national level (PLS 156/2009 and 236/2012), which have regulations projecting an expansion of the possibilities of agreements between prosecution and defense to immediate imposition of a criminal sanction. Finally, critics will be systematically structured in face of the bargained justice and plea bargaining, revealing their undeniable troubles and inconsistencies that lead to violations of the fundamental premises of criminal procedure in a democratic state. Consequently, it will enforce the importance of a critic viewpoint toward trends of expanding consensual opportunities in criminal justice. / Neste trabalho, inserido na ?rea de concentra??o Sistema Penal e Viol?ncia e na linha de pesquisa Sistemas Jur?dico-Penais Contempor?neos, objetiva-se desenvolver uma an?lise cr?tica das tend?ncias de expans?o dos espa?os de consenso na justi?a criminal brasileira, fundamentalmente a partir da introdu??o de mecanismos negociais, como o instituto da barganha, que, em termos amplos, possibilita a concretiza??o antecipada do poder punitivo por meio do reconhecimento de culpabilidade consentido do acusado em troca, geralmente, do benef?cio de redu??o em sua puni??o. Trata-se de forte inclina??o no cen?rio internacional, que se pauta cada vez mais pelo debatido objetivo de acelera??o procedimental, o qual, atualmente, avan?a al?m de tais pretens?es e chega a justificar a imposi??o de san??es penais sem aten??o ?s regras do devido processo. Ap?s a defini??o introdut?ria dos contornos das ideias de oportunidade e consenso, desenhar-se-?o as principais caracter?sticas da barganha, especialmente a partir do marcante exemplo estadunidense. Em seguida, questionar-se-? a ader?ncia de tais mecanismos ?s premissas dos sistemas processuais penais e apresentar-se-?o aspectos relevantes do panorama internacional com o objetivo de demonstrar a amplitude das tend?ncias aqui estudadas. Por outro lado, considerando o cen?rio brasileiro atual, estudar-se?o as possibilidades de consenso, que se autorizam no ?mbito dos Juizados Especiais Criminais e por meio do instituto da dela??o premiada. Em seguida, analisar-se-?o as propostas legislativas atualmente em discuss?o em ?mbito nacional (PLS 156/2009 e 236/2012), as quais apresentam regula??es com a amplia??o das possibilidades de acordos entre acusa??o e defesa para imposi??o imediata de uma san??o penal. Por fim, estruturar-se?o sistematicamente cr?ticas ? justi?a negocial e ao instituto da barganha, desvelando suas incontorn?veis aporias e inconsist?ncias que acarretam viola??es a premissas fundamentais do processo penal de um Estado Democr?tico de Direito. Assim, apontar-se-? a import?ncia da postura questionadora frente ?s tend?ncias de expans?o dos espa?os de consenso na justi?a criminal.
249

Aplicação do modelo da soma-ponderada-de-gases-cinza a sistemas com superfícies não cinzas

Fonseca, Roberta Juliana Collet da January 2017 (has links)
A radiação térmica é o principal mecanismo de transferência de calor em fenômenos que envolvem meios participantes em temperaturas elevadas, tais como em processos de combustão. A dependência fortemente irregular do coeficiente de absorção em relação ao número de onda torna desafiador o estudo de situações em que a radiação é apenas parte de um problema mais complexo. A exatidão do cálculo da radiação fica condicionada à solução da equação da transferência radiativa (RTE) por meio da integração linha-por-linha (LBL), sendo, muitas vezes, impraticável, em virtude do esforço computacional requerido para contabilizar as centenas de milhares ou milhões de linhas espectrais do coeficiente de absorção. Alternativamente, modelos espectrais, como a soma-ponderada-de-gases-cinza (WSGG), têm sido empregados de maneira eficaz na obtenção de resultados em substituição à integração LBL. Nessa dissertação, o modelo WSGG é aplicado na solução da transferência de calor radiativa em um sistema unidimensional, formado por duas placas planas paralelas infinitas e preenchido por uma mistura homogênea de dióxido de carbono e vapor de água, considerando-se perfis distintos de temperatura. Diferentemente da maioria dos estudos da literatura que empregam a mesma geometria, mas com paredes negras, o presente trabalho supõe superfícies cinzas e não cinzas. O objetivo central é, portanto, avaliar o erro em se assumir fronteiras negras quando estas não apresentam esse comportamento. Os resultados para o modelo WSGG aplicado a superfícies não cinzas, cinzas e negras são comparados com a solução linha-por-linha para paredes não cinzas. As análises dos desvios entre as soluções pelo modelo da soma-ponderada-de-gases-cinza e pela integração LBL mostram que a suposição de paredes negras, para casos em que as superfícies deveriam ser consideradas não cinzas, pode levar a erros de até 50% nos resultados para o fluxo de calor e para o termo fonte radiativo. / Thermal radiation is the main heat transfer mechanism in phenomena that involves high temperatures, such as in combustion processes. The strongly irregular dependence of the absorption coefficient on the wavenumber makes challenger the study of situations in which the radiation is only part of a more complex problem. The accuracy of the calculation of the radiation is conditioned to the solution of the radiative transfer equation (RTE) by line-by-line (LBL) integration, being frequently impracticable, due to the computational effort required to account for the hundreds of thousands or millions spectral lines of the absorption coefficient. Alternatively, spectral models, such as the weighted-sum-of-gray-gases (WSGG) model, have been used with success to obtain results in comparison to LBL integration. In this study, the WSGG model is applied to solve the radiative heat transfer in a one-dimensional system, formed by two infinite flat parallel plates and filled by a homogeneous mixture of carbon dioxide and water vapor, for different temperature profiles. Unlike most studies of the literature that employ the same geometry, but with black walls, the present work supposes gray and non-gray surfaces. The central objective is, therefore, to evaluate the error in assuming black boundaries when they do not present this behavior. The results for the WSGG model applied to non-gray, gray and black surfaces are compared with the line-by-line solution for non-gray walls. Analyzes of the deviations between the solutions by the weighted-sum-of-gray-gases model and the LBL integration show that the assumption of black walls, for cases where the surfaces should be considered as non-gray, may lead to errors of up to 50% in results for the heat flux and the radiative source term.
250

Avaliação do valor diagnóstico da escala de avaliação clínica da demência (CDR) utilizando o sistema de escore de soma das caixas para detecção de comprometimento cognitivo e demência

Lima, Andrea Pontes Vasconcelos January 2016 (has links)
Base teórica: Apesar de o escore da soma das caixas da escala de avaliação clínica da demência (CDR-SB) ser amplamente utilizado, sua aplicabilidade na avaliação do estadiamento da gravidade da demência e sua acurária para detectar as categorias diagnósticas não foram normatizadas em várias partes do mundo, inclusive no Brasil. Objetivo: O objetivo deste estudo foi avaliar a validade diagnóstica de CDR-SB na detecção e no estadiamento do comprometimento cognitivo e da demência em uma amostra de pacientes brasileiros com comprometimento cognitivo leve amnéstico (CCL amnéstico), doença de Alzheimer (DA) e demência vascular (DV). Métodos: Os dados foram obtidos a partir do banco de dados do ambulatório de demência do Hospital de Clínicas de Porto Alegre (HCPA) e incluíram 407 participantes com idade superior a 50 anos (115 controles saudáveis, 41 pacientes com CCL amnéstico, 165 pacientes com DA e 86 pacientes com DV ou demência mista). Curvas ROC foram geradas para detectar os melhores pontos de cortes de CDR-SB. A escolaridade média foi 4 anos. Resultados: Um ponto de corte de CDR-SB ≥0,5 permite identificar corretamente indivíduos com CCL amnéstico de controles normais (sensibilidade de 100% e especificidade de 98,3%). Um ponto de corte ≥4,5 identifica corretamente os pacientes com CCL amnéstico dos pacientes com demência, todos juntos ou separadamente (DA e DV) (sensibilidade de 96,4% e especificidade de 100%) em 96,9% dos indivíduos. Os melhores intervalos de CDR-SB correspondentes aos escores globais de CDR foram de 0,5 a 4,0 para um escore global de 0,5; 4,5 a 8,0 para um escore global de 1,0; 8,5 a 14,0 para um escore global de 2,0; e 14,5 a 18,0 para um escore global de 3,0. Quando aplicados à amostra de validação, os escores variaram de 0,87 a 0,97. Conclusão: O escore CDR-SB apresentou boa validade clínica para detectar e classificar a gravidade de prejuízos cognitivos na população brasileira. / Background: The Clinical Dementia Rating Scale sum of the boxes (CDR-SB) score has been widely used its utility in staging dementia severity and accuracy to detect diagnostic categories in sociodemographic and cultural diverse regions of the world remains untested. Objective: The aim of this study was to evaluate the CDR-SB diagnostic validity in detecting and staging cognitive impairment/dementia in a sample of Brazilian patients with amnestic mild cognitive impairment (aMCI), Alzheimer’s disease (AD), and vascular dementia (VD). Methods: Data were obtained from the Dementia Clinic of Hospital de Clínicas de Porto Alegre (HCPA) database and included 407 participants (115 healthy controls, 41 aMCI, 165 AD and, 86 VD). Receiver operating characteristic curves were generated to detect best CDR-SB cutoffs. Average education was 4 years. Results: A CDR-SB cutoff ≥0.5 was obtained to correctly identify aMCI from normal controls (sensitivity of 100% and specificity of 98.3%). The cutoff ≥4.5 correctly identified aMCI from dementia patients altogether or separately (AD and VD) (sensitivity of 96.4% and specificity of 100%) in 96.9% of the individuals. Optimal ranges of CDR-SB scores corresponding to the global CDR scores were 0.5 to 4.0 for a global score of 0.5, 4.5 to 8.0 for a global score of 1.0, 8.5 to 14.0 for a global score of 2.0, and 14.5 to 18.0 for a global score of 3.0. When applied to the validation sample, scores ranged from 0.87 to 0.97. Conclusion: The CDR-SB showed good clinical validity to detect and classify severity of cognitive impairment a Brazilian population.

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