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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.
341

Analogie et saisie discursive de l'expérience sonore : du sensible à l'intelligible / Analogy experience of sound and speech : from perception to meaning

Pinard, Dominique 08 December 2018 (has links)
Comme toute expérience humaine, la relation au sonore appelle le langage, qui contribue à l‟inscrire dans la vie des individus et des communautés. Récurrente cependant chez les locuteurs, l‟expression d‟une difficulté particulière à parler des phénomènes acoustiques doit-elle être attribuée à l‟irréductibilité essentielle du perçu au dire, à d‟éventuelles lacunes de la langue dans la saisie de l‟expérience auditive, ou encore à la spécificité d‟une situation dans laquelle le discours, attaché au sonore par le double lien du signans et du signatum, réactive à sa source le procès sémiotique ? Mettant en évidence le fait que parler des sons est toujours parler de notre relation aux phénomènes acoustiques, l‟étude, basée sur une analyse de corpus, s‟intéresse à la façon dont le discours témoigne - et participe - de l‟inscription de l‟expérience sonore au coeur de l‟être au monde. Utilisant les ressources de l‟approche cognitive de l‟analogie (Hofstadter, Sander, 2013), elle s‟attache aux relations unissant, du sonore au musical, les processus de catégorisation auditive aux diverses modalités de saisie discursive du perçu. Si, comme en témoigne l‟analyse, ce sont bien les mêmes analogies qui participent de la relation aux phénomènes auditifs et de l‟usage signifiant du sonore en langue, le discours sur le son permet-il de mieux comprendre les enjeux du lien originaire unissant, dans et par l‟expérience acoustique, l‟exploration du sensible à l‟engagement de l‟aventure du sens? / Like any human experience, the relationship to sound calls for language, which contributes to engaging it in the lives of individuals and communities. Speakers, though, often claim to encounter special difficulties when talking about acoustic phenomena. Should this situation be attributed to the essential irreductibility of percept to speech, to possible deficiencies of language in the field of auditory experience or to the specificity of a situation in which speech, bound both by signans and signatum to sound, has to reactivate the semiotic process at its source? Highlighting the fact that talking about soundsalways means talking about our relation to acoustic phenomena, this study is based on a corpus analysis and focuses on the way speech bears witness to and takes part in the central contribution of acoustic experience to “being in the world“. Based on the cognitive approach of analogy (Hofstadter, Sander, 2013), it focuses - from acoustic to musical points of view - on the links between auditory categorization processes and the different modalities of “speech on sound“. If, as the analysis suggests, analogies which play a part in auditory perception are the same as those which contribute to the significant useof sound in language, can speech on sound enable us to better understand what is at stake in the original link binding, in and by acoustic experience, the exploration of the sensitive universe to the adventure of meaning ?
342

Quelle rationalité pour les esprits animaux ? : étude sur le comportement d'investissement des entrepreneurs en incertitude non probabilisable / What rationality to the animal spirits ? : study on the investment behavior of entrepreneurs in non probabilistic uncertainty

Lainé, Michaël 15 September 2014 (has links)
Sur fond d’incertitude radicale, les entrepreneurs ne peuvent s’en remettre à un calcul précis de rentabilité. Pour les anticipations d’investissement, ils ont recours à leurs esprits animaux, c’est-à-dire un jugement analogique instinctif sur le futur associé à une décision émotionnelle automatique par rapport à lui en fonction de motivations. La notion remonte à l’Antiquité. Elle était synonyme d’influx nerveux. Si l’on interroge les neurosciences d’aujourd’hui, ce sont les marqueurs somatiques qui l’éclairent. Nos émotions servent à arrêter la réflexion, restreindre l’espace des possibles et valoriser certaines options. Elles contribuent à l’intelligence de nos décisions. C’est l’excès, de cognition ou d’émotion, qui est à éviter. Les émotions servent également à réviser ou renforcer nos croyances. Par leur mouvement propre, elles peuvent créer des cycles, ce que nous proposons d’appeler « le paradoxe de la confiance ». Une confiance élevée prépare le terrain de la chute future. À l’inverse, une confiance basse met peu à peu en place les conditions du retournement de conjoncture. Notre travail propose une analyse du raisonnement inductif en économie, à l’origine de l’élaboration de scénarios anticipatifs. Le capital culturel et symbolique semble également orienter les esprits animaux. Notre enquête empirique établit l’existence d’un lien entre capital culturel et prise de risque. Elle dessine aussi une typologie des esprits animaux à même de saisir l’hétérogénéité des entrepreneurs. 11 familles sont dégagées, en fonction de leurs motivations, émotions, capitaux culturels, comportements d’investissement et scénarios anticipatifs privilégiés. / In a background of fundamental uncertainty, entrepreneurs cannot rely on a precise calculus of profitability. For their investment expectations, they have to lean on their animal spirits, that is an analogical, instinctive judgment about the future associated with an automatic emotional decision under the guidance of motivations. The notion traces back to the Ancient times. She was then synonymous with “nerve impulse”. Nowadays, if one probes neuroscience, it appears that somatic markers could shed some light on them. Emotions are useful to stop thoughts, restrict the states of nature and value certain options. They contribute to the intelligence of decisions. It is the excess, be it of cognition or emotion, that is detrimental. Emotions also serve to update or strengthen our beliefs. By their own momentum, they can create cycles, which I propose to dub “the confidence paradox”. When confidence is high, the terrain for the future fall is being prepared. Conversely, when it is low, little by little the conditions for a reversal are being staged. Our work proposes an analysis of inductive reasoning responsible for the elaboration of anticipative scripts. Cultural and symbolic capital also appears to come into play. Our empirical inquiry establishes a link between cultural capital and risk-taking. It outlines as well a clustering of animal spirits so as to grasp the heterogeneity of entrepreneurs. 11 different sorts are outlined and sorted by their motivations, emotions, cultural capital, investment behaviors and preferred anticipative scripts.
343

La Critique de la raison pure, une œuvre inachevée

Westra, Adam 08 1900 (has links)
RÉSUMÉ: Selon Kant, il faut rendre la Critique plus compréhensible. Cela revient à doter son exposition d’un plus haut degré de lucidité (Helligkeit), c’est-à-dire combiner la clarté discursive avec une clarté intuitive. Pour ce faire, nous représentons les grandes lignes de la structure discursive de la Critique sous la forme d’un modèle emprunté à la description de la formation du caractère moral esquissé dans l’Anthropologie. Ainsi, la raison est d’abord régie par son « instinct de connaissance » (Wißbegierde, Erkenntnistrieb), qui la plonge dans un état de vacillement (Schwankender Zustand). Ensuite, elle réagit par du dégoût (Überdruß), ce rejet ouvrant la voie à l’introspection (Selbsterkenntnis) proprement critique. La raison entreprend alors une révolution de son mode de pensée spéculatif (Revolution der Denkungsart) consistant à passer, sous l’égide du devoir moral (Pflicht), de la malhonnêteté à l’honnêteté, envers soi-même ainsi qu’envers autrui. Il s’agit, en un mot, d’une « renaissance » (Wiedergeburt) morale. / ABSTRACT: According to Kant, the Critique must be made more comprehensible. This entails increasing the degree of lucidity (Helligkeit) of the exposition, i.e., by combining discursive clarity with intuitive clarity. In order to accomplish this task, the lines of force of the discursive structure of the Critique are represented here in the form of a model borrowed from Kant’s description of the formation of moral character in the Anthropology. Thus, reason is at first ruled by its “knowledge-instinct” (Wißbegierde, Erkenntnistrieb), which, however, plunges it into a state of vacillation (Schwankender Zustand). Reason eventually reacts with disgust (Überdruß), and this rejection opens the way to a properly critical introspection (Selbsterkenntnis). Finally, reason undergoes a revolution of its speculative mode of thinking (Revolution der Denkungsart), i.e., a transition, under the aegis of moral duty (Pflicht), from dishonesty to honesty, towards itself and towards others: in a word, a moral “rebirth” (Wiedergeburt).
344

Truth and Tradition in Plato and the Cambridge Platonists

Koffman, Jordan 01 October 2009 (has links)
Both Plato and the Cambridge Platonists hold the view that moral knowledge depends primarily on cognitive resources which are innate to the mind. There is, nevertheless, a need for our minds to be prompted through experience in order for knowledge to occur. The following study is an attempt to reconstruct and compare the accounts in Plato and the Cambridge Platonists of the empirical conditions that are required for knowledge. For Plato, these conditions are a result of a decline in political and psychological constitutions, through which the intellect is increasingly developed. Dialectical analysis of received customs, laws, opinions, and language may then reveal the moral ideas upon which the polity was initially based and which remain implicit in common sense throughout the historical decline. Philosophical knowledge consists of a recollection of the ancient wisdom which was revealed to the original lawgiver by the gods. In the Cambridge Platonists, philosophical knowledge likewise consists of a recollection of revealed knowledge that stood at the foundation of a form of life, namely, Judaism. The revival of ancient Greek and Jewish philosophical theories in modern times heralds the end of history, in which the complete system of knowledge is both attainable and necessary for salvation. From the perspective of humanity as a whole, knowledge is initially granted through revelation, then generally forgotten, and finally recollected in a highly intellectual age of deteriorating morality and stability. The esoteric traditions of knowledge, coupled with recent developments in science and philosophy, act as the prompts for knowledge, given an intuitive basis that has been formed through the spread of Christianity. This intuitive basis serves as the concrete way in which the natural anticipations of the mind are gradually shaped in order to recognize the truth when it appears in a shrouded manner in modern philosophy. Both Plato and the Cambridge Platonists are critics of the similar intellectual trends in their times and they respond with similar arguments; however, unlike Plato, the Cambridge Platonists are unable to connect their rational critique with their genetic critique of modern ideas, rendering the latter ineffective. / Thesis (Ph.D, Philosophy) -- Queen's University, 2009-09-24 16:19:49.145
345

Moranapho : apprentissage non supervisé de la morphologie d'une langue par généralisation de relations analogiques

Lavallée, Jean-François 08 1900 (has links)
Récemment, nous avons pu observer un intérêt grandissant pour l'application de l'analogie formelle à l'analyse morphologique. L'intérêt premier de ce concept repose sur ses parallèles avec le processus mental impliqué dans la création de nouveaux termes basée sur les relations morphologiques préexistantes de la langue. Toutefois, l'utilisation de ce concept reste tout de même marginale due notamment à son coût de calcul élevé.Dans ce document, nous présenterons le système à base de graphe Moranapho fondé sur l'analogie formelle. Nous démontrerons par notre participation au Morpho Challenge 2009 (Kurimo:10) et nos expériences subséquentes, que la qualité des analyses obtenues par ce système rivalise avec l'état de l'art. Nous analyserons aussi l'influence de certaines de ses composantes sur la qualité des analyses morphologiques produites. Nous appuierons les conclusions tirées de nos analyses sur des théories bien établies dans le domaine de la linguistique. Ceci nous permet donc de fournir certaines prédictions sur les succès et les échecs de notre système, lorsqu'appliqué à d'autres langues que celles testées au cours de nos expériences. / Recently, we have witnessed a growing interest in applying the concept of formal analogy to unsupervised morphology acquisition. The attractiveness of this concept lies in its parallels with the mental process involved in the creation of new words based on morphological relations existing in the language. However, the use of formal analogy remain marginal partly due to their high computational cost. In this document, we present Moranapho, a graph-based system founded on the concept of formal analogy. Our participation in the 2009 Morpho Challenge (Kurimo:10) and our subsequent experiments demonstrate that the performance of Moranapho are favorably comparable to the state-of-the-art. We studied the influence of some of its components on the quality of the morphological analysis produced as well. Finally, we will discuss our findings based on well-established theories in the field of linguistics. This allows us to provide some predictions on the successes and failures of our system when applied to languages other than those tested in our experiments.
346

Numerical simulations of supersonic turbulent wall-bounded flows

Ben Nasr, Ouissem 16 May 2012 (has links) (PDF)
This work deals with spatially-evolving supersonic turbulent boundary layers over adiabatic and cold walls at M∞ = 2 and up to Re0 ≈ 2600 using 3 different SGS models. The numerical methodology is based on high-order split-centered scheme to discretize the convective fluxes of the Navier-Stokes equations . For the adiabatic case, it is demonstrated that all SGS models require a comparable minimum grid-refinement in order to capture accurately the near-wall-turbulence. Overall, the models exhibit correct behavior when predictiong the dynamic properties, but show different performances for the temperature distribution in the near-wall region. For the isothermal case, it is found that the compressibility effects are not enhanced due to the wall cooling. As expected, the total temperature fluctuations are not negligible in the near-wall region. The study shows that the anti-correlation linking both velocity and temperature fields, derived from the Morkovin's hypothesis, is not satisfied.
347

Metaphor and First Peter: the essential role of the minds of father- God’s children in spiritual conflict with a special focus on 1:13

McMillen, Melvin 24 October 2011 (has links)
Section 1 of this thesis develops an eclectic meta-model of metaphor analysis that is subsequently applied to the paraenetic metaphors in First Peter. This comprehensive and broadly-based theory provides for the integration of First Peter‟s metaphors in the analysis of the epistle‟s persuasive, knowledge-change rhetoric. The bulk of this thesis is a largely suggestive and primarily inductive study of the major paraenetic metaphors within the conceptual and rhetorical world of First Peter, especially “gird up the loins of your mind” and “be sober,” which are crucially bound up with the epistle‟s first grammatical imperative: “hope on the grace to come …” (1:13). I argue that 1:13 is central to all of First Peter‟s paraenetic statements through a sequential survey of these injunctions in the order provided by the text. While “girding the loins” is capable of a more generic or other specific interpretations, I argue for a conflict connotation. First Peter presupposes a situation of spiritual peril, with the danger especially related to the “mind.” The greatest threat is not from persecution but from ignorance, an irrational fear of humans rather than a rational fear of God, along with other sinful “passions”–forces strengthened by the menacing Devil. By means of courageous faith believers must “stand firm” with a disciplined and focused mind oriented vertically towards and hoping fully upon God‟s present and future grace (5:12) to the exclusion of sin, ready for spiritual battle–just as Christ was (4:1). In addition, I maintain that honouring/glorifying God is the ultimate goal of First Peter‟s paraenesis. Consistent with this, the metaphorical organization of “space” in the letter gives evidence of the prioritizing of the vertical axis over the horizontal. In this connection, I challenge Troy Martin‟s view of the Christian life as a journey, finding First Peter to image it as essentially a stationary waiting for final salvation to come to them. Finally, I seek to demonstrate that the Fatherhood of God is the dominant metaphor for First Peter as a whole, a complex image that unites its metaphors, paraenesis, and overall message. / New Testament / D.Th. (New Testament)
348

A "influência" do mito babilônico da criação, enuma elish, em Gênesis, 1,1 -2,4a.

Antonio Ivemar da Silva Pontes 26 July 2010 (has links)
Dentre os vários campos de interesse das Ciências da Religião, o sagrado e seu impacto nas culturas dos diversos povos e épocas, tem sido objeto de estudo para muitos que enveredam nesse campo tão vasto. Através de pesquisa bibliográfica, o presente trabalho, à luz das Ciências da Religião, se presta a fazer uma análise hermenêutica comparativa sobre a relação entre o poema babilônico da criação, Enuma Elish, e o relato bíblico da criação em Gênesis 1,12,4a. Esse estudo, que tem como base a Teologia Comparada, busca fazer uma análise sobre a influência que uma cultura exerce quando interage com outra. Pretende sinalizar algumas semelhanças e diferenças entre esses dois textos de culturas e épocas diferentes. Procura ainda ajudar o leitor a perceber de que maneira o mito pode ser entendido e de que forma ele pode ser empregado no campo científico. Após a análise do levantamento de dados, percebemos que há alguns elementos em comum entre os dois poemas. Dentre eles destacamos: a criação do universo, do firmamento, dos astros e do homem. Percebemos, portanto, que de fato, quando um povo interage com outro de cultura diferente da sua, acaba havendo uma influência mútua de um povo em relação ao outro. / Among the various fields of interest of the Religion Sciences, the sacred and its impact over the cultures of different peoples and ages, has been studied by many who go through that vast field. Through bibliographic studies, this project, under the lights of the Religion Sciences, intends to make an hermeneutics comparative analysis about the relationship between the Babylonian poem of Creation, Enuma Elish, and the biblical account of creation in Genesis 1. This study, which is based on Comparative Theology, seeks to analyze the influence that a culture has when interacting with others. It aims to identify some similarities and differences between these two texts from different cultures and times. It also seeks to help the reader to understand how the myth can be understood and how it can be employed in the scientific field. After analyzing the survey data, we realize that there are some elements in common between the two poems. Among them we highlight: the creation of the universe, the firmament, the stars and man. We see, therefore, that in fact, when people interact with another culture than theirs, it comes to happen a mutual influence of one people over the other.
349

Analogie microonde appliquée à l'étude de la diffraction par des arbres, par des particules atmosphériques et des micro-organismes / Application of the microwave analogy to study the scattering properties of trees, atmospheric particles and microorganisms

Saleh, Hassan 09 November 2017 (has links)
Cette thèse élargie le champ des applications de l’analogie microonde en adaptant les techniques de fabrication permettant de contrôler les analogues et en développant un outil versatile et précis pour réaliser les mesures. L’analogie microonde consiste à transposer à l’échelle microonde les objets dont nous souhaitons étudier la diffraction en créant un analogue respectant le même rapport dimension sur longueur d’onde, et les mêmes propriétés morphologiques électromagnétiques. Une attention particulière a été portée aux objets faiblement diffractant ayant des niveaux SER aussi faibles que -60 dBm2. A la suite de la caractérisation des réflexions parasites et de celle du bruit aléatoire perturbant les mesures, une nouvelle technique d’optimisation du paramétrage des appareils de mesure a été proposée. Elle comporte notamment un réglage des puissances de source en fonction des angles de bistatisme et un filtrage temporel, par switch, qui a été mis en place et paramétré pour filtrer les signaux parasites mesurés. Les bénéfices de ces diverses optimisations des paramètres de mesures ont été démontrés et ils ont permis de mesurer précisément des niveaux de SER très faibles. De plus, la mise en œuvre de la fabrication additive a permis de réaliser des analogues de géométrie maîtrisée avec des permittivités relatives locales à la carte ayant des parties réelles dans la gamme de 1 à 3 ; la permittivité étant ajustée par contrôle de la porosité. Les trois principales études présentées concernent : des sphéroïdes de faible permittivité, analogues de micro-algues, des agrégats de suies de forme complexes, et des scènes forestières composées d’analogues d’arbres et de véhicules. / This thesis widens the application of the microwave analogy by adopting the appropriate techniques to create objects of controlled shapes and electromagnetic properties using novel manufacturing technologies, as well as by developing a versatile setup providing accurate measurements. Microwave analogy is a useful approach to investigate a scattering problem when the targets have nanometric or metric sizes. The experiment is scaled to the microwave range and the target is mimicked by a centimeter-sized analog, while maintaining the same initial wavelength over target’s dimension ratio and conserving the same geometric and electromagnetic properties. A special attention is given to low scattering targets with RCS levels down to -60 dBm2. The random noise of the measurement setup was characterized and a novel optimization technique was proposed which consists of an angular decomposition of the bistatic region with different power profiles. The undesired reflections within the anechoic chamber were identified and a Hardgating system was installed, allowing to filter out the stray signals. In addition, additive manufacturing technologies were involved in the fabrication of analogs and a novel technique was proposed to obtain targets with “on-demand” shapes and local values of their complex permittivity. We can manufacture low scattering analogs of the real part of permittivity for any value between 1 and 3 by creating well controlled porous structures. The three main targets are studied: low permittivity spheroids, analogs of microalgae, soot aggregates analogs with complex shape, and scaled forest scene composed of tree analogs with some metal vehicle analogs.
350

Novas estratégias para seleção de variáveis por intervalos em problemas de classificação

Fernandes, David Douglas de Sousa 26 August 2016 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2017-06-20T13:50:43Z No. of bitstreams: 1 arquivototal.pdf: 7102668 bytes, checksum: abe19d798ad952073affbf4950f62d29 (MD5) / Made available in DSpace on 2017-06-20T13:50:43Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 7102668 bytes, checksum: abe19d798ad952073affbf4950f62d29 (MD5) Previous issue date: 2016-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In Analytical Chemistry it has been recurring in the literature the use of analytical signals recorded on multiple sensors combined with subsequent chemometric modeling for developing new analytical methodologies. For this purpose, it uses generally multivariate instrumental techniques as spectrometry ultraviolet-visible or near infrared, voltammetry, etc. In this scenario, the analyst is faced with the option of selecting individual variables or variable intervals so to avoid or reduce multicollinearity problems. A well-known strategy for selection of variable intervals is to divide the set of instrumental responses into equal width intervals and select the best interval based on the performance of the prediction of a unique range in the regression by Partial Least Squares (iPLS). On the other hand, the use of interval selection for classification purposes has received relatively little attention. A common practice is to use the iPLS regression method with the coded class indices as response variables to be predicted; that is the basic idea behind the release of the Discriminant Analysis by Partial Least Squares (PLS-DA) for classification. In other words, interval selection for classification purposes has no development of native functions (algorithms). Thus, in this work it is proposed two new strategies in classification problems using interval selection by the Successive Projections Algorithm. The first strategy is named Successive Projections Algorithm for selecting intervals in Discriminant Analysis Partial Least Squares (iSPA-PLS-DA), while the second strategy is called Successive Projections Algorithm for selecting intervals in Soft and Independent Modeling by Class Analogy (iSPA-SIMCA). The performance of the proposed algorithms was evaluated in three case studies: classification of vegetable oils according to the type of raw material and the expiration date using data obtained by square wave voltammetry; classification of unadulterated biodiesel/diesel blends (B5) and adulterated with soybean oil (OB5) using spectral data obtained in the ultraviolet-visible region; and classification of vegetable oils with respect to the expiration date using spectral data obtained in the near infrared region. The proposed iSPA-PLS-DA and iSPA-SIMCA algorithms provided good results in the three case studies, with correct classification rates always greater than or equal to those obtained by PLS-DA and SIMCA models using all variables, iPLS-DA and iSIMCA with a single selected interval, as well as SPA-LDA and GA-LDA with selection of individual variables. Therefore, the proposed iSPA-PLS-DA and iSPA-SIMCA algorithms can be considered as promising approaches for use in classification problems employing interval selection. In a more general point of view, the possibility of using interval selection without loss of the classification accuracy can be considered a very useful tool for the construction of dedicated instruments (e.g. LED-based photometers) for use in routine and in situ analysis. / Em Química Analítica tem sido recorrente na literatura o uso de sinais analíticos registrados em múltiplos sensores combinados com posterior modelagem quimiométrica para desenvolvimento de novas metodologias analíticas. Para esta finalidade, geralmente se faz uso de técnicas instrumentais multivariadas como a espectrometrias no ultravioleta-visível ou no infravermelho próximo, voltametria, etc. Neste cenário, o analista se depara com a opção de selecionar variáveis individuais ou intervalos de variáveis de modo de evitar ou diminuir problemas de multicolinearidade. Uma estratégia bem conhecida para seleção de intervalos de variáveis consiste em dividir o conjunto de respostas instrumentais em intervalos de igual largura e selecionar o melhor intervalo com base no critério de desempenho de predição de um único intervalo em regressão por Mínimos Quadrados Parciais (iPLS). Por outro lado, o uso da seleção de intervalo para fins de classificação tem recebido relativamente pouca atenção. Uma prática comum consiste em utilizar o método de regressão iPLS com os índices de classe codificados como variáveis de resposta a serem preditos, que é a idéia básica por trás da versão da Análise Discriminante por Mínimos Quadrados Parciais (PLS-DA) para a classificação. Em outras palavras, a seleção de intervalos para fins de classificação não possui o desenvolvimento de funções nativas (algoritmos). Assim, neste trabalho são propostas duas novas estratégias em problemas de classificação que usam seleção de intervalos de variáveis empregando o Algoritmo das Projeções Sucessivas. A primeira estratégia é denominada de Algoritmo das Projeções Sucessivas para seleção intervalos em Análise Discriminante por Mínimos Quadrados Parciais (iSPA-PLS-DA), enquanto a segunda estratégia é denominada de Algoritmo das Projeções Sucessivas para a seleção de intervalos em Modelagem Independente e Flexível por Analogia de Classe (iSPA-SIMCA). O desempenho dos algoritmos propostos foi avaliado em três estudos de casos: classificação de óleos vegetais com relação ao tipo de matéria-prima e ao prazo de validade utilizando dados obtidos por voltametria de onda quadrada; classificação de misturas biodiesel/diesel não adulteradas (B5) e adulteradas com óleo de soja (OB5) empregando dados espectrais obtidos na região do ultravioleta-visível; e classificação de óleos vegetais com relação ao prazo de validade usando dados espectrais obtidos na região do infravermelho próximo. Os algoritmos iSPA-PLS-DA e iSPA-SIMCA propostos forneceram bons resultados nos três estudos de caso, com taxas de classificação corretas sempre iguais ou superiores àquelas obtidas pelos modelos PLS-DA e SIMCA utilizando todas as variáveis, iPLS-DA e iSIMCA com um único intervalo selecionado, bem como SPA-LDA e GA-LDA com seleção de variáveis individuais. Portanto, os algoritmos iSPA-PLS-DA e iSPA-SIMCA propostos podem ser consideradas abordagens promissoras para uso em problemas de classificação empregando seleção de intervalos de variáveis. Num contexto mais geral, a possibilidade de utilização de seleção de intervalos de variáveis sem perda da precisão da classificação pode ser considerada uma ferramenta bastante útil para a construção de instrumentos dedicados (por exemplo, fotômetros a base de LED) para uso em análise de rotina e de campo.

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