955 resultados para pseudo-raiva


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Este estudio forma parte de una investigación más amplia que trata de la capacidad expresiva de los sistemas perspectivos1. Bajo esta premisa hemos reflexionado sobre los métodos utilizados por los artistas del trecento italiano para representar la tercera dimensión. Hemos analizado un amplio número de obras, con un doble objetivo: El primero, obtener datos que otorguen consistencia y fiabilidad a una clasificación que nos ayuda a tipificar el espacio perspectivo en esta etapa predecesora de la perspectiva «correcta» (lineal o cónica). El segundo, extrapolar sus características a la construcción de escenarios pseudo-perspectivos mediante la modificación y creación de gráficos tridimensionales por computadora. Este proceso se ha utilizado para extraer los esquemas que nos sirven como herramienta para explorar nuevos caminos en la representación perspectiva, alejados de la lógica euclidiana. Con este propósito se aportan esquemas formales de representaciones clasificadas en diferentes tipos, que posteriormente se transforman para efectuar la construcción volumétrica de los escenarios.

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Memristori on yksi elektroniikan peruskomponenteista vastuksen, kondensaattorin ja kelan lisäksi. Se on passiivinen komponentti, jonka teorian kehitti Leon Chua vuonna 1971. Kesti kuitenkin yli kolmekymmentä vuotta ennen kuin teoria pystyttiin yhdistämään kokeellisiin tuloksiin. Vuonna 2008 Hewlett Packard julkaisi artikkelin, jossa he väittivät valmistaneensa ensimmäisen toimivan memristorin. Memristori eli muistivastus on resistiivinen komponentti, jonka vastusarvoa pystytään muuttamaan. Nimens mukaisesti memristori kykenee myös säilyttämään vastusarvonsa ilman jatkuvaa virtaa ja jännitettä. Tyypillisesti memristorilla on vähintään kaksi vastusarvoa, joista kumpikin pystytään valitsemaan syöttämällä komponentille jännitettä tai virtaa. Tämän vuoksi memristoreita kutsutaankin usein resistiivisiksi kytkimiksi. Resistiivisiä kytkimiä tutkitaan nykyään paljon erityisesti niiden mahdollistaman muistiteknologian takia. Resistiivisistä kytkimistä rakennettua muistia kutsutaan ReRAM-muistiksi (lyhenne sanoista resistive random access memory). ReRAM-muisti on Flash-muistin tapaan haihtumaton muisti, jota voidaan sähköisesti ohjelmoida tai tyhjentää. Flash-muistia käytetään tällä hetkellä esimerkiksi muistitikuissa. ReRAM-muisti mahdollistaa kuitenkin nopeamman ja vähävirtaiseman toiminnan Flashiin verrattuna, joten se on tulevaisuudessa varteenotettava kilpailija markkinoilla. ReRAM-muisti mahdollistaa myös useammin bitin tallentamisen yhteen muistisoluun binäärisen (”0” tai ”1”) toiminnan sijaan. Tyypillisesti ReRAM-muistisolulla on kaksi rajoittavaa vastusarvoa, mutta näiden kahden tilan välille pystytään mahdollisesti ohjelmoimaan useampia tiloja. Muistisoluja voidaan kutsua analogisiksi, jos tilojen määrää ei ole rajoitettu. Analogisilla muistisoluilla olisi mahdollista rakentaa tehokkaasti esimerkiksi neuroverkkoja. Neuroverkoilla pyritään mallintamaan aivojen toimintaa ja suorittamaan tehtäviä, jotka ovat tyypillisesti vaikeita perinteisille tietokoneohjelmille. Neuroverkkoja käytetään esimerkiksi puheentunnistuksessa tai tekoälytoteutuksissa. Tässä diplomityössä tarkastellaan Ta2O5 -perustuvan ReRAM-muistisolun analogista toimintaa pitäen mielessä soveltuvuus neuroverkkoihin. ReRAM-muistisolun valmistus ja mittaustulokset käydään läpi. Muistisolun toiminta on harvoin täysin analogista, koska kahden rajoittavan vastusarvon välillä on usein rajattu määrä tiloja. Tämän vuoksi toimintaa kutsutaan pseudoanalogiseksi. Mittaustulokset osoittavat, että yksittäinen ReRAM-muistisolu kykenee binääriseen toimintaan hyvin. Joiltain osin yksittäinen solu kykenee tallentamaan useampia tiloja, mutta vastusarvoissa on peräkkäisten ohjelmointisyklien välillä suurta vaihtelevuutta, joka hankaloittaa tulkintaa. Valmistettu ReRAM-muistisolu ei sellaisenaan kykene toimimaan pseudoanalogisena muistina, vaan se vaati rinnalleen virtaa rajoittavan komponentin. Myös valmistusprosessin kehittäminen vähentäisi yksittäisen solun toiminnassa esiintyvää varianssia, jolloin sen toiminta muistuttaisi enemmän pseudoanalogista muistia.

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Let G be a semi-simple algebraic group over a field k. Projective G-homogeneous varieties are projective varieties over which G acts transitively. The stabilizer or the isotropy subgroup at a point on such a variety is a parabolic subgroup which is always smooth when the characteristic of k is zero. However, when k has positive characteristic, we encounter projective varieties with transitive G-action where the isotropy subgroup need not be smooth. We call these varieties projective pseudo-homogeneous varieties. To every such variety, we can associate a corresponding projective homogeneous variety. In this thesis, we extensively study the Chow motives (with coefficients from a finite connected ring) of projective pseudo-homogeneous varieties for G inner type over k and compare them to the Chow motives of the corresponding projective homogeneous varieties. This is done by proving a generic criterion for the motive of a variety to be isomorphic to the motive of a projective homogeneous variety which works for any characteristic of k. As a corollary, we give some applications and examples of Chow motives that exhibit an interesting phenomenon. We also show that the motives of projective pseudo-homogeneous varieties satisfy properties such as Rost Nilpotence and Krull-Schmidt.

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Efficient hill climbers have been recently proposed for single- and multi-objective pseudo-Boolean optimization problems. For $k$-bounded pseudo-Boolean functions where each variable appears in at most a constant number of subfunctions, it has been theoretically proven that the neighborhood of a solution can be explored in constant time. These hill climbers, combined with a high-level exploration strategy, have shown to improve state of the art methods in experimental studies and open the door to the so-called Gray Box Optimization, where part, but not all, of the details of the objective functions are used to better explore the search space. One important limitation of all the previous proposals is that they can only be applied to unconstrained pseudo-Boolean optimization problems. In this work, we address the constrained case for multi-objective $k$-bounded pseudo-Boolean optimization problems. We find that adding constraints to the pseudo-Boolean problem has a linear computational cost in the hill climber.

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"Para describir la vida política de las democracias antiguas nos vemos forzados a servirnos de términos que utilizamos para las democracias modernas. Pero hay que tener cuidado de no engañarse. Pues las mismas palabras contemplan a menudo las realidades más diversas" (Reverdin, 1945: 201). Esta afirmación nos autoriza a preguntarnos si hay o no una conexión entre los demagogou atenienses y lo que nosotros entendemos por "demagogos". El lexema ingresó a los idiomas modernos por una traducción al francés de una traducción latina de la Política de Aristóteles en el siglo XIV d.C. (Robert, 1954: s.v.), donde ya era patente el carácter peyorativo del lexema. Durante los últimos cincuenta años, los especialistas han analizado las ocurrencias del campo léxico de la demagogia desde una perspectiva histórico- sociológica y en ese sentido coinciden en que estos vocablos en su origen eran "neutros" (Connor, 1992; Lane, 2012). Ostwald, por su parte, opina que la connotación peyorativa del término probablemente se deba a Aristóteles, específicamente a un pasaje de la Política (4.4.1292a4-38) (1986: 201). Sin embargo, contamos con testimonios del lexema de fines del siglo V a.C. y principios del IV a.C. donde es posible entender cierta connotación negativa. Dentro del conjunto de testimonios se encuentra el Contra Alcibíades del Pseudo Andócides. El presente trabajo, complementario de análisis anteriores en el corpus del siglo V a.C., tiene como objetivo analizar el mencionado lexema en su cotexto a la luz de una perspectiva que concibe las palabras como piezas lingüísticas susceptibles de variación semántica incluso en un mismo estadio sincrónico, aplicando conceptos de las teorías de la Nueva Retórica y del Análisis del Discurso

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"Para describir la vida política de las democracias antiguas nos vemos forzados a servirnos de términos que utilizamos para las democracias modernas. Pero hay que tener cuidado de no engañarse. Pues las mismas palabras contemplan a menudo las realidades más diversas" (Reverdin, 1945: 201). Esta afirmación nos autoriza a preguntarnos si hay o no una conexión entre los demagogou atenienses y lo que nosotros entendemos por "demagogos". El lexema ingresó a los idiomas modernos por una traducción al francés de una traducción latina de la Política de Aristóteles en el siglo XIV d.C. (Robert, 1954: s.v.), donde ya era patente el carácter peyorativo del lexema. Durante los últimos cincuenta años, los especialistas han analizado las ocurrencias del campo léxico de la demagogia desde una perspectiva histórico- sociológica y en ese sentido coinciden en que estos vocablos en su origen eran "neutros" (Connor, 1992; Lane, 2012). Ostwald, por su parte, opina que la connotación peyorativa del término probablemente se deba a Aristóteles, específicamente a un pasaje de la Política (4.4.1292a4-38) (1986: 201). Sin embargo, contamos con testimonios del lexema de fines del siglo V a.C. y principios del IV a.C. donde es posible entender cierta connotación negativa. Dentro del conjunto de testimonios se encuentra el Contra Alcibíades del Pseudo Andócides. El presente trabajo, complementario de análisis anteriores en el corpus del siglo V a.C., tiene como objetivo analizar el mencionado lexema en su cotexto a la luz de una perspectiva que concibe las palabras como piezas lingüísticas susceptibles de variación semántica incluso en un mismo estadio sincrónico, aplicando conceptos de las teorías de la Nueva Retórica y del Análisis del Discurso

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Efficient numerical models facilitate the study and design of solid oxide fuel cells (SOFCs), stacks, and systems. Whilst the accuracy and reliability of the computed results are usually sought by researchers, the corresponding modelling complexities could result in practical difficulties regarding the implementation flexibility and computational costs. The main objective of this article is to adapt a simple but viable numerical tool for evaluation of our experimental rig. Accordingly, a model for a multi-layer SOFC surrounded by a constant temperature furnace is presented, trained and validated against experimental data. The model consists of a four-layer structure including stand, two interconnects, and PEN (Positive electrode-Electrolyte-Negative electrode); each being approximated by a lumped parameter model. The heating process through the surrounding chamber is also considered. We used a set of V-I characteristics data for parameter adjustment followed by model verification against two independent sets of data. The model results show a good agreement with practical data, offering a significant improvement compared to reduced models in which the impact of external heat loss is neglected. Furthermore, thermal analysis for adiabatic and non-adiabatic process is carried out to capture the thermal behaviour of a single cell followed by a polarisation loss assessment. Finally, model-based design of experiment is demonstrated for a case study.

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Les Homélies et les Reconnaissances du Pseudo-Clément, aussi appelées Pseudo-Clémentines, sont des témoins privilégiés du foisonnement intellectuel et théologique des premiers siècles chrétiens. Alors que la recherche moderne a longtemps tenté de déterminer les différentes étapes de leur constitution (ne posant pour seule conclusion certaine que l’existence d’un « Écrit de base » à leur origine), le présent mémoire offre une enquête littéraire qui permettra de situer l’état final des Pseudo-Clémentines dans leur contexte rédaction, en établissant comment elles dialoguent avec les principaux groupes religieux de leur milieu (chrétiens, judéo-chrétiens, juifs, gnostiques et païens). Dans ce cadre, cette étude définit le dualisme pseudo-clémentin selon ses quatre aspects : la règle de syzygies ou des couples antagonistes, qui veut que tout, dans la création, soit organisé par Dieu en couples opposés ; les prophéties masculine et féminine, dont la première apporte la vérité alors que la seconde apporte le mensonge ; la doctrine des deux rois, dont l’un, qui est bon, gouverne le royaume du monde à venir, alors que l’autre, qui est mauvais, règne sur le monde présent ; la doctrine des deux voies, dont l’une mène au salut et l’autre à la perdition. Après une analyse de ces thèmes au sein des Pseudo-Clémentines, qui révèle les différences qui existent entre les deux textes, ces mêmes motifs sont recherchés dans la littérature apparentée, en particulier dans les textes gnostiques de la bibliothèque de Nag Hammadi, les textes découverts à Qumrân et la littérature judéo-chrétienne. Les conclusions dégagées permettent de définir précisément le dualisme des Homélies et celui des Reconnaissances, d’identifier des fonctions polémiques et rhétoriques de ce dualisme et de cerner des groupes religieux possiblement alliés et ennemis des Pseudo-Clémentines.

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Nas últimas duas décadas a temática ambiental adquiriu corpo no Brasil e, ainda que em descompasso com relação aos Estados Unidos da América e Europa, trouxe a necessidade de análises intersetoriais e interdisciplinares dos problemas derivados da ação antrópica. Uma das facetas desta ascensão temática à agenda política do país foi a elaboração da Política Nacional de Defesa Civil (Resolução CONDEC n.º 2, de 12 de dezembro de 1994) e do Sistema Nacional de Defesa Civil, o SINDEC (através do Decreto Federal nº. 5.376 de 17 de fevereiro de 2005). Ao lado de determinados alarmismos, e em um cenário dominado por incertezas (ou certezas probabilísticas), as ações da Defesa Civil deveriam se pautar por um pragmatismo responsável. O vasto campo de sua atuação previu, através da Classificação e da Codificação de Desastres (CODAR), os desastres naturais ligados a sismologia e os desastres mistos ligados a sismicidade induzida. Tais eventos, e suas referências, sempre constituíram uma espécie de literatura cinzenta em se tratando de um país “isento de terremotos”. Para confrontar a percepção de risco dos estudantes de Geografia com as evidências dos principais centros de pesquisas sísmicas, aplicamos um questionário por correio eletrônico aos discentes das principais faculdades de Geografia do país.

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La classificazione di dati geometrici 3D come point cloud è un tema emergente nell'ambito della visione artificiale in quanto trova applicazione in molteplici contesti di guida autonoma, robotica e realtà aumentata. Sebbene nel mercato siano presenti una grande quantità di sensori in grado di ottenere scansioni reali, la loro annotazione costituisce un collo di bottiglia per la generazione di dataset. Per sopperire al problema si ricorre spesso alla domain adaptation sfruttando dati sintetici annotati. Questo elaborato si pone come obiettivo l'analisi e l'implementazione di metodi di domain adaptation per classificazione di point cloud mediante pseudo-labels. In particolare, sono stati condotti esperimenti all'interno del framework RefRec valutando la possibilità di sostituire nuove architetture di deep learning al modello preesistente. Tra queste, Transformer con mascheramento dell'input ha raggiunto risultati superiori allo stato dell'arte nell'adattamento da dati sintetici a reali (ModelNet->ScanNet) esaminato in questa tesi.

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The present paper describes the synthesis of molecularly imprinted polymer - poly(methacrylic acid)/silica and reports its performance feasibility with desired adsorption capacity and selectivity for cholesterol extraction. Two imprinted hybrid materials were synthesized at different methacrylic acid (MAA)/tetraethoxysilane (TEOS) molar ratios (6:1 and 1:5) and characterized by FT-IR, TGA, SEM and textural data. Cholesterol adsorption on hybrid materials took place preferably in apolar solvent medium, especially in chloroform. From the kinetic data, the equilibrium time was reached quickly, being 12 and 20 min for the polymers synthesized at MAA/TEOS molar ratio of 6:1 and 1:5, respectively. The pseudo-second-order model provided the best fit for cholesterol adsorption on polymers, confirming the chemical nature of the adsorption process, while the dual-site Langmuir-Freundlich equation presented the best fit to the experimental data, suggesting the existence of two kinds of adsorption sites on both polymers. The maximum adsorption capacities obtained for the polymers synthesized at MAA/TEOS molar ratios of 6:1 and 1:5 were found to be 214.8 and 166.4 mg g(-1), respectively. The results from isotherm data also indicated higher adsorption capacity for both imprinted polymers regarding to corresponding non-imprinted polymers. Nevertheless, taking into account the retention parameters and selectivity of cholesterol in the presence of structurally analogue compounds (5-α-cholestane and 7-dehydrocholesterol), it was observed that the polymer synthesized at the MAA/TEOS molar ratio of 6:1 was much more selective for cholesterol than the one prepared at the ratio of 1:5, thus suggesting that selective binding sites ascribed to the carboxyl group from MAA play a central role in the imprinting effect created on MIP.

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Enormous amounts of pesticides are manufactured and used worldwide, some of which reach soils and aquatic systems. Glyphosate is a non-selective herbicide that is effective against all types of weeds and has been used for many years. It can therefore be found as a contaminant in water, and procedures are required for its removal. This work investigates the use of biopolymeric membranes prepared with chitosan (CS), alginate (AG), and a chitosan/alginate combination (CS/AG) for the adsorption of glyphosate present in water samples. The adsorption of glyphosate by the different membranes was investigated using the pseudo-first order and pseudo-second order kinetic models, as well as the Langmuir and Freundlich isotherm models. The membranes were characterized regarding membrane solubility, swelling, mechanical, chemical and morphological properties. The results of kinetics experiments showed that adsorption equilibrium was reached within 4 h and that the CS membrane presented the best adsorption (10.88 mg of glyphosate/g of membrane), followed by the CS/AG bilayer (8.70 mg of glyphosate/g of membrane). The AG membrane did not show any adsorption capacity for this herbicide. The pseudo-second order model provided good fits to the glyphosate adsorption data on CS and CS/AG membranes, with high correlation coefficient values. Glyphosate adsorption by the membranes could be fitted by the Freundlich isotherm model. There was a high affinity between glyphosate and the CS membrane and moderate affinity in the case of the CS/AG membrane. Physico-chemical characterization of the membranes showed low values of solubility in water, indicating that the membranes are stable and not soluble in water. The SEM and AFM analysis showed evidence of the presence of glyphosate on CS membranes and on chitosan face on CS/AG membranes. The results showed that the glyphosate herbicide can be adsorbed by chitosan membranes and the proposed membrane-based methodology was successfully used to treat a water sample contaminated with glyphosate. Biopolymer membranes therefore potentially offer a versatile method to eliminate agricultural chemicals from water supplies.

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The establishment of the most stable structures of eight membered rings is a challenging task to the field of conformational analysis. In this work, a series of 2-halocyclooctanones were synthesized (including fluorine, chlorine, bromine and iodine derivatives) and submitted to conformational studies using a combination of theoretical calculation and infrared spectroscopy. For each compound, four conformations were identified as the most important ones. These conformations are derived from the chair-boat conformation of cyclooctanone. The pseudo-equatorial (with respect to the halogen) conformer is preferred in vacuum and in low polarity solvents for chlorine, bromine and iodine derivatives. For 2-fluorocyclooctanone, the preferred conformation in vacuum is pseudo-axial. In acetonitrile, the pseudo-axial conformer becomes the most stable for the chlorine derivative. According to NBO calculations, the conformational preference is not dictated by electron delocalization, but by classical electrostatic repulsions.

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PURPOSE: To evaluate the frequency of different types of glaucoma at the Hospital das Clínicas of Campinas State University. METHODS: Cross-sectional study of 329 patients followed at the Glaucoma Service of Campinas State University from October 1 to December 20, 2000. The frequency of each type of glaucoma and the treatment were analyzed. RESULTS: There were 329 patients examined at the Glaucoma Service: 132 (40.1%) were referred to the service as glaucoma suspects and 197 (59.9%) as glaucoma patients. Ninety of the 132 glaucoma suspects had glaucoma (68.2%) and 42 are still under investigation (31.8%). Among the 329 patients, 283 (86%) had glaucoma, 42 (12.8%) were glaucoma suspects, 2 (0.6%) had ocular hypertension and 2 (0.6%) did not have glaucoma. There were 530 eyes with glaucoma: 298 (56.2%) with primary open angle glaucoma, 108 (20.4%) with chronic angle closure glaucoma, 21 (4%) with glaucoma following cataract surgery, 19 (3.6%) congenital glaucoma and 16 (3%) with low-tension glaucoma. All patients received initial clinical treatment with IOP-lowering medication. After a mean follow up of 10.5 months, 89 (16.8%) underwent laser therapy: 72 (13.6%) iridotomy, 7 (1.3%) trabeculoplasty and 10 (1.9%) panphotocoagulation. A hundred and seventy nine (33%) eyes required surgical treatment. CONCLUSION: The most frequent types of glaucoma were primary open angle and angle closure glaucoma. Low tension glaucoma and glaucoma associated with exfoliation syndrome were uncommon in this population.

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We report the study of four children with bilateral basal ganglia calcifications (BGC) visualized on CT scan. Epilepsy was the clinical manifestation of three patients whose laboratory investigation revealed abnormal calcium metabolism. The first aim of this paper is to call attention to a treatable entity that can cause epileptic syndromes in infancy and childhood. The second purpose is to review the literature comparing with our fourth child who presented encephalopathy with BGC.