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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.
21

Snabb automatiserad benämning som screeninginstrument vid kognitiva störningar : En klinisk studie baserad på AQT

Backlund, Josefine, Lindqvist, Anna January 2009 (has links)
A Quick Test (AQT) Färg och Form är ett test av snabb automatiserad benämning avsett att detektera kognitiva störningar. Det består av tre delar som var och en utgörs av 40 visuella stimuli som skall benämnas så snabbt som möjligt. Tidigare studier har indikerat att AQT skiljer personer med Alzheimers sjukdom från friska kontroller med högre precision än det ofta använda Mini-Mental-Testet (MMT). I denna studie undersöktes för första gången om AQT-resultat kunde predicera diagnosen hos en konsekutiv serie patienter vid en minnesklinik samt relationen mellan AQT-resultat och biomarkörer (likvorproteiner) för neurodegenerativ sjukdom. 492 svarsblanketter från AQT Färg och Form analyserades och diagnostisk prediktion samt korrelation med nivån av likvorproteiner fastställdes för de 374 första patienterna i serien. Resultaten tyder på att AQT Färg och Form kan vara känsligt för vissa lindriga kognitiva sviktsymptom som förekommer hos personer remitterade för minnesbesvär men inte alltid känsligt för lindriga grader av demens. AQT-data korrelerade måttligt med nivån av patologiska likvorproteiner, troligen avspeglande förhöjda nivåer i Alzheimergruppen. Ytterligare forskning på konsekutiva fallserier behövs för att fastställa testets diagnostiska diskriminationsförmåga i klinisk praxis. / A Quick Test (AQT) Color-Form is a test that uses rapid automatized naming in order to identify cognitive impairment. It is divided into three parts, each of which consists of 40 stimuli that are to be named as quickly as possible. Previous studies have indicated that AQT separates patients with Alzheimer’s disease from normal controls with higher accuracy than the commonly used Mini-Mental State Examination (MMSE). The purpose of this study was to investigate, for the first time, whether AQT results collected from a consecutive series of patients at a Memory Clinic would be able to predict the diagnosis. Another aim was to study the possible relation between AQT results and Cerebrospinal Fluid (CSF) biomarkers for neurodegenerative diseases. 492 forms from AQT Color-Form tests were analyzed and diagnostic prediction and correlation with level of CSF biomarkers were determined for the first 374 patients. The results imply that AQT Color-Form may be sensitive to some symptoms of benign memory impairment that is found in patients admitted to a Memory Clinic, but that it is not always sensitive to mild degrees of dementia. Further research consecutive series of patients is needed in order to determine the diagnostic abilities of discrimination in clinical practice.
22

Arbetsterapeuters användning av Mini Mental Test (MMT) inom kommunal rehabilitering / (Occupational Therapists use of the Mini Mental State Examination (MMSE) in community based rehabilitation)

Gren, Karin January 2011 (has links)
Sammanfattning Inom den kommunala rehabiliteringen möter arbetsterapeuten personer med vitt skilda slag av sjukdomar och funktionsnedsättningar. En av de vanligare grupperna är personer, som av olika skäl drabbas av kognitiva nedsättningar. Arbetsterapeuten bedömer personer med kognitiva funktionsnedsättningar bl.a. med hjälp av olika bedömningsinstrument. Screening -instrumentet Mini Mental Test (MMT) är ett av de mest använda. Det finns forskning där MMT använts för att diagnostisera eller utvärdera interventioner, däremot behövs mer kunskap om hur arbetsterapeuter använder och uppfattar MMT. Syftet med denna studie var att beskriva arbetsterapeuters användning av Mini Mental Test (MMT) inom kommunal rehabilitering. Data samlades in med hjälp av ett frågeformulär, som sändes till samtliga arbetsterapeuter anställda inom Örebro kommun. Svaren analyserades med hjälp av beskrivande statistik. Resultatet visade att 79 % av arbetsterapeuterna använde MMT för att bedöma en klients kognitiva nedsättning. Den vanligaste orsaken till att ett MMT initierades var remiss från läkare (85 %). Sjuttiotre procent angav att de inte tolkade resultatet, innan remissvaren sändes åter. Sextiosju procent använde resultatet från MMT till att skriva remissvar medan 15 % angav att resultatet användes som underlag, för att planera vilka åtgärder de skulle välja.
23

Mode Matching Analysis and Design of Substrate Integrated Waveguide Components

Kordiboroujeni, Zamzam 14 November 2014 (has links)
The advent of Substrate Integrated Circuit (SIC) technology, and specifically Substrate Integrated Waveguide (SIW) technology has made it feasible to design and fabricate low loss and high quality factor (Q-factor) microwave and millimeter wave structures on a compact and integrable layout and at a low cost. The SIW structure is the planar realization of the conventional rectangular waveguide (RWG). In this technology, the side walls of the waveguide are replaced with two rows of metallic vias, which are connecting two conductor sheets, located at the top and bottom of a dielectric slab. The motivation for this thesis has been to develop an analytical method to efficiently analyze SIW structures, and also design different types of passive microwave components based on this technology. As SIW structures are imitating waveguide structures in a planar format, the field distributions inside these structures are very close to those in waveguides. However, due to the very small substrate height in conventional planar technologies, and also the existence of a row of vias, instead of a solid metallic wall, there is a reduced set of modes in SIW compared to regular waveguide. This fact has given us an opportunity to deploy efficient modal analysis techniques to analyze these structures. In this thesis, we present a Mode Matching Techniques (MMT) approach for the analysis of H-plane SIW structures. One of the areas of application, which can significantly benefit from having an efficient analytical method, is designing and optimizing new circuits. Having such an analytical tool, which is faster than commercially available field solvers by an order of magnitude, new components can be designed, analyzed and optimized in a fast and inexpensive manner. Based on this technique, various types of passive microwave components including filters, diplexers, power dividers and couplers, some of which are among the first to be reported in SIW technology, are designed and analyzed in this thesis. Also based on this technique, the most accurate formula for the effective waveguide width of the SIW is presented in this thesis. In order to provide means to excite and measure SIW components, transitions between these structures and other planar topologies like microstrip and coplanar waveguide (CPW) are needed. More importantly, low-reflection transitions to microstrip are required to integrate SIW circuits with active components, and therefore it is vital to provide low-reflection transitions so that the component design is independent of the influences of the transitions. In this thesis, a new wideband microstrip-to-SIW transition, with the lowest reported reflection coefficient, is also introduced. / Graduate / 0544 / zkordi@ece.uvic.ca
24

Métrologie fonctionnelle par Calibre virtuel sur Machine à mesurer tridimensionnelle

Eric, Pairel 20 December 1995 (has links) (PDF)
Le tolérancement géométrique défini par la normalisation est étudié de façon détaillée suivant une présentation structurée. Cette étude fait apparaître l'importance de la notion de surface théorique composée dans les spécifications géométriques fonctionnelles telles que les systèmes de références ou certains types de tolérancement tel que l'exigence du maximum de matière. Ces spécifications peuvent être vérifiées par les méthodes traditionnelles de contrôle au marbre et de contrôle par calibre. Les logiciels des machines à mesurer tridimensionnelles (MMT), ne permettent pas de construire, de façon conforme à la norme, les systèmes de références sur les surfaces palpées de la pièce, ni de reproduire les contrôles par calibre. Une nouvelle approche de la métrologie est proposée pour les logiciels de ces machines dont le premier objectif est de palier à ces limites. Suivant cette approche les spécifications sont contrôlées par le résultat de l'assemblage d'un "calibre virtuel" avec les surfaces palpées de la pièce. Ceci permet de contrôler directement les conditions fonctionnelles que doit remplir la pièce. Le calibre virtuel, défini par le métrologue grâce aux menus du logiciel, est une construction parfaite de plusieurs surfaces théoriques élémentaires, telles que des plans ou des cylindres, qui sont appelées "calibres élémentaires". Différentes propriétés peuvent être données aux calibres élémentaires leur permettant, par exemple, de "s'ajuster" aux surfaces palpées. Ces propriétés permettent d'effectuer une multitude de contrôles et de mesures fonctionnels. Une maquette informatique implémentant ce modèle a été développée. L'utilisation de cette maquette est illustrée sur un exemple industriel et permet de montrer la simplicité et l'efficacité de l'approche proposée
25

Anti-Fascist Aesthetics from Weimar to MoMA: Siegfried Kracauer & the Promise of Abstraction for Critical Theory

Seijo, Maxximilian 21 March 2019 (has links)
This thesis re-examines the life's work of German-American critical theorist, Siegfried Kracauer, to recover abstraction from tacit historical associations with modern fascism. Evoked in critical theory more generally, the abstraction-to-fascism-teleology imagines 20th century fascism as the dialectical fulfillment of modern alienation. Rooting such alienation in the flawed Liberal and Marxist conceptions of monetary relations, critical theorists conduct their aesthetic analyses via ambivalent condemnations of abstraction’s assumed primordial alienation. In the thesis, I critique the abstraction-to-fascism-teleology through an affirmation of neochartalist political economy’s conception of money’s essential publicness and abundance. Drawing from this abstract legal mediation, I trace Kracauer’s various condemnations of abstraction along the terms of his embodied contradiction among the WWII and Cold War fiscal mobilizations to illuminate repressed pleas for abstract mediation within his work and midcentury aesthetic realism broadly. Further, I move from the midcentury moment to the Weimar moment in order to locate potential in Kracauer’s early affirmation of abstraction as a communal medium. I find such affirmations neglected in the Liberal and Marxist responses to the unemployment crises of the Great Depression in Germany. By looking to Kracauer’s Weimar essays on architecture and photography, as well as a reading of Fritz Lang’s Metropolis (1927), I pinpoint historical and contemporary promise in their commitment to the inclusive potential of abstraction’s (no)thing- ness, a commitment that was mirrored in the proposed monetary issuance of the WTB public works plan of 1932, which was ultimately rejected by the Social Democratic Party of Germany in the lead up to their defeat in the parliamentary elections of 1933 and the Nazis’ rise to power.
26

Preparation and Characterization of Polyethylene Terephthalate/Montmorillonite Nanocomposites by In-situ Polymerization Method

Labde, Rohan Khushal 14 June 2010 (has links)
No description available.
27

Study and Development of Nonwovens made of Electrospun Composite Nanofibers / Etude et développement de non-tissés fait en nanofibres composites obtenues par électrofilage

Almuhamed, Sliman 14 December 2015 (has links)
L’électrofilage est actuellement la méthode la plus utilisée pour la production de nanofibres grâce à sa simplicité, sa reproductibilité et la possibilité d’être industrialisée. Grâce à leurs propriétés particulières telles qu’un grand rapport surface-volume, une porosité inter-fibre élevée et une grande capacité d’adsorption, les nanofibres électrofilées sont de bons candidats pour de nombreuses applications telles que la filtration, les masques respiratoires, les matériaux composites, etc. Cependant, certaines applications particulières, telles que les capteurs, les systèmes d'administration contrôlée de médicaments ou les super condensateurs, exigent que les nanofibres doivent présenter des propriétés complémentaires telles que la conductivité électrique, la porosité de surface de nanofibres, l’hydrophobicité, ou d’autres propriétés particulières. Certains nanomatériaux comme les nanotubes de carbone, la silice mésoporeuse ordonnée, les argiles, ont des propriétés particulières comme la conductivité électriques élevée des nanotubes de carbone, la porosité des matériaux de silice mésoporeuse ordonnée ou de l’argile. Ces propriétés des nanomatériaux peuvent être les fonctions complémentaires cherchées. Dans notre étude, des non-tissés composés de nanofibres de polyacrylonitrile chargées par nanotubes de carbone à multi-parois (MWNT), de la montmorillonite sodique (MMT-Na) ou de la silice mésoporeuse ordonnée (de type SBA-15), sont produits par électrofilage. Les résultats montrent que l’insertion de MWNT rend le non-tissé conducteur en augmentant la conductivité électrique volumique par six ordres de grandeur (de ~ 2×10-12 à ~ 3×10-6 S/m) avec un très faible seuil de percolation de 0.5 % massique. Lorsque le non-tissé est soumis à une compression, la conductivité électrique volumique augmente en augmentant la pression (jusqu’à ~ 2 kPa). Ces non-tissés conducteurs sont très intéressants pour le développement des capteurs à faible amplitude. Les résultats montrent aussi que l’accessibilité des pores des particules inorganiques (c’est-à-dire, les mésopores de SBA-15 et l’espace interfoliaire de MMT-Na) insérées dans la structure nano fibreuse est encore possible. Il a été trouvé que plus de 50% des mésopores de SBA-15 insérées sont encore accessibles quelles que soit les conditions de l’électrofilage et la fraction massique de SBA-15. En outre, l’insertion de ces particules inorganiques apporte plus de stabilité thermique aux nanofibres composites. / Electrospinning is the most common method for the production of nanofibres due to its simplicity, repeatability, and the ability to be scaled up. Owing to their advanced properties like the high surface-to-volume ratio, high interfibrous porosity, high adsorption capacity, etc. electrospun nanofibers are good candidates for many applications such as filtration, respiratory masks, composite materials and others. However, some specific applications including sensors, controlled drug delivery systems, supercapacitors, etc. still require complimentary functions that do not exist in pristine nanofibers in their basic structure like the electrical conductivity, surface porosity of the nanofibers, hydrophobicity, and others.Nanomaterials like carbon nanotubes, ordered mesoporous silica, layered silicate, etc. are characterized by particular properties like the high electrical conductivity of carbon nanotubes, the porosity of ordered mesoporous silica or layered silicate. These particular properties of nanomaterials can fulfill of the targeted functions.In our study, nonwovens made from nanofibers of polyacrylonitrile incorporated with multiwalled carbon nanotubes (MWNT), layered silicate type Na-montmorillonite (Na-MMT) or ordered mesoporous silica type SBA-15 are successfully produced by electrospinning.Results reveal that the incorporation of MWNT altered the electrical state of the nonwoven from insolent to conductor where the volume electrical conductivity increased by six order of magnitude (from ~ 2×10-12 to ~ 3×10-6 S/m) with a very low percolation threshold of about 0.5 wt%. The application of mechanical pressure to the conductive nonwoven causes an increase in the volume electrical conductivity with the increase of the applied pressure (up to ~ 2 kPa). Such conductive nonwoven is very interesting for the development of sensor with low amplitude.Results also show that accessibility of the pores of the inorganic particles (i.e. mesopores of SBA-15 and interlayer space of Na-MMT) incorporated into the nanofibers is still possible. It is found that at least 50% of SBA-15 mesopores are still accessible whatever is the electrospinning conditions and SBA-15 mass fraction. In addition, the incorporation of the studied inorganic particles yields higher thermal stability for the composite nanofibers.
28

Conception du système de fabrication de pièces mécaniques en grand série : formalisation de la configuration géométrique (enveloppe) et cinématique de Machine-Outil Reconfigurable (MOR)

Aladad, Hasan 09 July 2009 (has links) (PDF)
Tous les secteurs industriels sont aujourd'hui soumis à une pression économique importante et à une concurrence internationale accrue de part la globalisation des marchés. Pour répondre à cet état de fait, les entreprises sont contraintes d'innover et d'améliorer le cycle d'élaboration des produits et/ou processus depuis l'idée jusqu'au la mise sur le marché des produits. L'évolutivité rapide des produits et de la concurrence ont conduit les entreprises industrielles à faire un pas supplémentaire en imaginant de nouveaux systèmes de fabrication pour assurer simultanément une haute productivité et une haute flexibilité avec la contrainte nouvelle de changements rapides de famille de pièces. Le principe de « reconfigurabilité » de système de fabrication répond à ces contraintes. Or, il faut aujourd'hui faire preuve d'une très grande réactivité, pouvoir répondre rapidement à l'apparition d'un nouveau produit (évolution du design) et/ou une nouvelle demande (fluctuation de volume) afin de rester compétitif. L'objectif de notre travail est de proposer une méthodologie de conception concernant les « Machines-Outils Reconfigurable » (MORs). Ces nouvelles machines-outils disposant de multibroches sont une réponse face aux fluctuations (changements fréquents) de la demande, de manière rapide et rentable en tenant compte du nombre croissant de variantes (variabilité en fonctionnalités et en volumes). La particularité de ce type de machine par rapport aux autres types conventionnels réside dans la possibilité d'évolution au niveau de la capacité et/ou de la flexibilité et d'exécuter simultanément plusieurs opérations à l'aide de broches actionnant de façon simultanée. Le domaine concerné porte sur la fabrication de famille de pièces mécaniques essentiellement prismatiques utilisant les techniques d'usinage (fraisage, opérations axiales
29

Use of Supercritical Propylene to Produce Polypropylene/Clay Nanocomposites via in situ Polymerization

Lisboa da Silva Neto, Manoel January 2014 (has links)
Nanocomposites have been receiving a lot the attention in the last decade from both industry and academia, since a small amount of nanofiller can significantly improve the materials properties. In the field of thermoplastics, polypropylene (PP) is one of the most used materials , due its easy processability, good balance of mechanical properties, and low cost. However, PP has certain shortcomings such as poor gas barrier and low thermal stability which limit its application. In order to be classified as nanocomposite the material needs to have at least one phase with one dimension less than 100nm. The properties achieved by nanocomposites will depend on the type of polymer, type of dispersed phase (filler), surface interaction between filler and polymer, and the production method. Nanofillers present many shapes and sizes, but they can be grouped in nanoparticles, nanotubes and nanoplates. Montmorillonite (MMT) is a clay that has been extensively studied to produce PP nanocomposites, due to its availability, high aspect ratio, high modulus and high cation exchange capacity, characteristics that result in composite with improved properties. Three different morphologies can be observed in PP/MMT nanocomposites: agglomerates (similar to the conventional composites); intercalated; or exfoliated. Among these morphologies, exfoliation is the most desirable and the hardest to be achieved in PP/MMT nanocomposites. Several methods have been used to produce PP nanocomposites. They can be grouped in three main groups: solution blending; melt processing; and in situ polymerization. In order to produce an exfoliated nanocomposite, some methods have assisted the exfoliation using supercritical fluids. Supercritical carbon dioxide is by far the most explored one. Polypropylene is a semi-crystalline polymer and its properties rely on amount of its crystallinity, which is related to its stereochemical configurations. Isotactic PP and syndiotactic PP result in a semi-crystalline polymer while atactic results in an amorphous polymer. Two catalyst systems can be used to produce isotactic PP: Metallocene and Ziegler-Natta (ZN). This research study was carried out in order to develop an appropriated process to produce PP/MMT nanocomposites with a high level of exfoliation using in situ polymerization assisted by supercritical propylene. The main idea is to use supercritical propylene to treat the montmorillonite before polymerization. In this process, the small molecules of propylene diffuse inside the clay galleries under supercritical conditions (high pressure and temperature) until reaching complete saturation. Once this saturation is reached the mixture of polypropylene and clay is catastrophically decompressed and fed into an autoclave reactor. The propylene polymerization reaction is them catalyzed by ZN catalyst. The pressure of the mixture of propylene-montmorillonite from the supercritical condition to the reactor autoclave decreased significantly, allowing propylene to expand and exfoliate the clay as it was fed in the reactor. Propylene in supercritical conditions was used in this works because it is the monomer for the subsequently polymerization and because its good properties at supercritical conditions. In order to evaluate the results the following methods were used: transmission electron microscopy (TEM) to investigate the nanoscale sample morphology and evaluate the clay exfoliation, X-ray diffraction (XRD) to determine interlamellar distance, d001, of the clay, differential scanning calorimetry (DSC) to determine the amount of crystallization of polymer and composite, thermogravimetric analysis (TGA) to determine composite clay content, scanning electron microscopy (SEM) to evaluate the morphology, and clay swelling test to evaluate the compatibility among various pairs clays-solvent. The first part of this work evaluated the interaction and swelling effects of different pairs of clay-solvent with or without sonication. This was necessary in order to choose the best clay to carry out the study. Four solvents with different polarity (chlorobenzene, toluene, cyclohexane and hexane) and eight clays (seven organically modified and one unmodified) were evaluated with or without sonication. Closite 15A and 93A presented the best results with different solvents and they were selected for further experiments. The experiments also showed that sonication improves the swelling of the clay. Initial screening of the polymerization reaction was carried out using two conditions: feeding supercritical propylene without clay and adding clay without the addition of supercritical fluid. The addition of supercritical propylene did not modify the morphology and properties of PP in comparison to the normal polymerization. The addition of Cloisite 15A or Cloisite 93A (pre-treated with toluene, not with supercritical propylene) produced nanocomposites. Although Cloisite 15A showed better results on the swelling tests, Cloisite 93A presented much better polymerization yield, therefore it was selected for further investigation using treatment with supercritical propylene. Cloisite93A was submitted to a treatment under four different supercritical propylene conditions (temperature and pressure) for thirty minutes. Each mixture was subsequently fed to the reactor through a catastrophic expansion inside an autoclave reactor running a propylene polymerization reaction. The results from XRD and TEM show a significant improvement on the exfoliation when treating the clay under supercritical propylene conditions followed by in situ polymerization, as compared to the in situ polymerization without treating the clay with supercritical propylene. In conclusion, the utilization of supercritical propylene has improved the dispersion of the clay at the nanoscale during the preparation of these nanocomposites by in situ polymerization.
30

STUDI DI TERMINOLOGIA CINESE: APPROCCI DIACRONICI E SVILUPPI APPLICATIVI CONTEMPORANEI / STUDIES OF CHINESE TERMINOLOGY: DIACHRONIC APPROACHES AND CONTEMPORARY APPLICATION DEVELOPMENT

LU, HUIZHONG 28 April 2014 (has links)
La ricerca intende illustrare le modalità applicative attraverso le quali si possono esprimere in lingua cinese le terminologie specialistiche dei campi tecnici e scientifici del XXI secolo. Un percorso che attraversa la storia delle scienze in Cina dal terzo secolo a.C. fino ai nostri giorni, ricostruisce le regole che passo dopo passo, non senza deviazioni e ripensamenti, gli studiosi cinesi hanno stabilito per creare e gestire le loro “parole” composte con innumerevoli caratteri, gli hanzi, simbolo della cultura e della civiltà cinese, icone che ancora oggi “parlano” ai lettori, espressioni grafiche di oggetti e di concetti. La presentazione dell'opera di Feng Zhiwei, uno tra i maggiori esponenti della terminologia cinese contemporanea, ci accompagna nell'approfondimento degli orientamenti degli studi terminologici cinesi e nel confronto con quelli euro americani, a partire dagli studi svolti da Eugen Wüster all'inizio del XX secolo. L'analisi della terminologia cinese nella tecnologia del fotovoltaico e nel mondo economico-finanziario, costituisce il terreno di verifica delle pratiche terminologiche in essere nella lingua cinese e delle tendenze nella costruzione neologica e neonimica. / This research aims to illustrate the methodes used for creation of the specialized terminologies in the technical and scientific fields in the XXI century’s Chinese language. A pathway crossing the history of sciences in China from the III century B.C. until our days, reconstructs the rules that step after step the Chinese scholars have established in order to create and manage their “words” with the lot of characters, the hanzi, symbol of the Chinese culture and civilization, icons that still today “speak” to the readers, graphical expressions of objects and concepts. The presentation of the work of Feng Zhiwei, one among the greatest exponents of the contemporary Chinese terminology, is our guideline in a close examination of the Chinese terminological studies’ orientations, in comparison with the euro-americans ones, starting from the studies developed by Eugen Wüster at the beginning of the XX century. The analysis of the Chinese terminology in the photovoltaic technology and in the economic-financial world, constitutes the ground of verification of the actual terminological practices in the Chinese language and the tendencies in the neological and neonymical construction.

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