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Sanchez, Tani Dianca. "Race and the Matrix Movie Trilogy." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/215411.
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Using a close textual and contextual analysis, I trace themes of gender and race in the Matrix trilogy, arguing for the presence of a parallel, embedded filmic narrative, one that neatly aligns with African-American critical traditions affirming subjugated ideologies, knowledges, communities and forms. Decoding the films through the lenses of race, womanist, film studies and cultural studies theories, I explore this signified, covert storyline through phenotypes, casting choices, plot twists, and extra filmic events. In this dissertation project, I argue that their preponderance, consistency, and coherence are evidence of deliberate commentary. I further claim that that the trilogy can be reasonably understood as a historically motivated critique of Whiteness and White supremacy, offering references to American slavery and ideologies, as well as to cross-racial ideological domination and collective, coalitional and revolutionary change. Since long standing racial and gender understandings (along with their attendant domination and oppression) persist, examining popular films with transformed constructions is useful in supporting frameworks for conceptual change.
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Rainbow, Marc E. "Effects of systemic flunixin meglumine, topical oxytetracycline, and topical prednisolone acetate on tear film proteinases innormal horses." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/9896.
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The purpose of this study was to determine the effects of three medical treatments, topical oxytetracycline, topical prednisolone acetate, and systemic flunixin meglumine, on the activity of two proteinases, matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), in equine tear film. The study design consisted of twelve ophthalmically normal horses separated into three groups of four in a cross-over study design. Each group was treated for 5 days with flunixin meglumine (500mg IM bid), topical 1% prednisolone acetate (0.2ml tid), or topical oxytetracycline (0.2ml tid), followed by a 9-day washout period. All topical medications were applied to the left eye and the right eye was treated with a placebo. Tears were collected before the first treatment on day one and the morning following the last treatment on day 5. Tear film proteinase activity was measured using gelatin zymography and measurements of optical density. Statistical analysis of the difference between the treated and untreated eyes and the eyes before and after treatment was performed using mixed effects model for ANOVA. When eyes were compared after treatment, there was no significant difference between treated and placebo eyes for MMP-2 or MMP-9 for any of the treatments. When post-treated eyes were compared to pre-treated eyes, there was a significant decrease in MMP-2 activity in the left eye of horses treated with flunixin meglumine (P=0.0259). There were no differences in MMP-2 and MMP-9 activity for the other treatments. In conclusion, topical 1% prednisolone acetate and topical oxytetracycline did not significantly change MMP-2 or MMP-9 activity in normal equine tear film. Systemic flunixin meglumine had an inhibitory, but questionable, effect on MMP-2 activity in normal equine tear film. This project was funded by Patricia Bonsall Stuart Award for Equine Research.Master of Science
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Estrada, Cárdenas Alba Sovietina. "Ciencia ficción y representación del mundo posmoderno en la Trilogía de Matrix." Montpellier 3, 2008. http://www.theses.fr/2008MON30031.
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Dans la Trilogie de Matrix, je trouve des constantes qui fournissent le texte filmique d´un fil événementiel, ainsi que des signes et des symboles qui convergent en lui donnant une unité; entre ces derniers se distingue la Matrix identifiée à la mère, et notamment à la matrice; ce symbolisme se trouve dans les images filmiques qui renvoient à l´union entre cette machine et les hommes qui sont connectés à elle pour l´alimenter. Dans ce contexte, la machine se met en évidence comme une mère qui souhaite ne jamais accoucher, car inversement à la mère qui nourrit son fœtus à travers le cordon ombilical, la Matrix s´alimente de l´énergie humaine à travers des fils qui l´unissent aux hommes. De ce qui précède, j´ai pu conclure: 1) La machine se convertit en une allégorie du contrôle social qu´exerce l´État et de l´exploitation de la force de travail. 2) Le fait que les humains sont connectés à la machine nous renvoie aussi à une similitude de l´époque actuelle où l´homme contemporain est plongé dans un contexte social dans lequel prédomine la technologie comme moyen de contrôle de l´esprit humain; ou monde virtuel que l´homme contemporain prend pour réel, comme le “monde web” ou la “World Wide Web”. À partir de ces hypothèses, et avec l´aide de la théorie sociocritique, j´ai réussi à construire un cadre théorique qui m´a permis d´aborder les structures sociales contemporaines à travers l´analyse des structures du texte filmique, par exemple, en identifiant la machine avec l´État contemporain j´ai pu voir comment le fonctionnement des Appareils Idéologiques d´État affecte le contrôle social des individusIn the Trilogy of Matrix I find constants which provide the filmic text with an event-driven thread, as well as signs and symbols which converge into giving a unit to it; among these last ones, the Matrix stands out compared to the mother and particularly to the womb (matrice). This symbolism is found in the filmic images which refer to the union between this machine and the men connected to her to feed her. In such context, the machine is presented as a mother who has never wished to give birth because, unlike the mother who nourishes her fetus through the umbilical cord, the Matrix feeds on human energy through the cables that wires it up to men. Of what precedes, I could conclude: 1) The machine becomes an allegory of the social control that the State exerts and of the exploitation of the work force. 2) The fact that human beings are connected to the machine also sends to a similarity of the present time where the man is sunk into a social context in which prevails technology as a means to control the human mind. I am referring to the virtual world that the contemporary man has assumed like real, like the “world web” or the “World Wide Web”. By means of these hypotheses, and with the aid of the sociocritic theory, I have succeed to build a theoretical frame that allowed me to approach the social structures through the analysis of the structures of the filmic text, for example, when identifying the machine with the contemporary State I could see how the operation of the Ideological Apparatus of State affects the social control of the individuals
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Sechogela, Thulaganyo P. "Vanadium dioxide nanocomposite thin film embedded in zinc oxide matrix as tunable transparent conductive oxide." Thesis, University of the Western Cape, 2013. http://hdl.handle.net/11394/4529.
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Philosophiae Doctor - PhDThis project is aimed at fabricating a smart material. Zinc oxide and vanadium dioxide have received a great deal of attention in recent years because they are used in various applications. ZnO semiconductor in particular has a potential application in optoelectronic devices such as light emitting diodes (LED), sensors and in photovoltaic cell industry as a transparent electrode. VO2 also has found application in smart windows, solar technology and infrared smart devices. Hence the need to synthesis or fabricate a new smart material using VO2 and an active ZnO based nano-composites family in which ZnO matrix will be hosting thermally active VO2 nano-crystals is the basis of this study. Since VO2 behave as an MIT Mott’s type oxides and exhibits a thermally driven semiconductor-metal phase transition at about 68 oC and as a direct result ZnO:VO2 nano-composites would exhibit a reversible and modulated optical transmission in the infra-red (IR) while maintaining a constant optical transmission in the UV-Vis range. The synthesis is possible by pulsed laser deposition and ion implantation. Synthesis by pulsed laser deposition will involve thin films multilayer fabrication. ZnO buffer layer thin film will be deposited on the glass and ZnO single crystals and subsequent layer of VO2 and ZnO will be deposited on the substrate. X-ray diffraction (XRD) reveals that the series of ZnO thin films deposited by Pulsed Laser Deposition (PLD) on glass substrates has the hexagonal wurtzite structure with a c-axis preferential orientation. In addition the XRD results registered for VO2 samples indicate that all thin films exhibits a monoclinic VO2 (M) phase. UV-Vis NIR measurements of multilayered structures showed the optical tunability at the near-IR region and an enhanced transparency (>30 %) at the visible range.
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Baril-Gosselin, Simon. "Investigation of the Resin Film Infusion Process for Multi-scale Composites Based on the Study of Resin Flow, Void Formation and Carbon Nanotube Distribution." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37212.
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The aerospace industry is steadily increasing its use of polymer-matrix composites (PMCs) in airframe structures as it seeks to benefit from the high specific in-plane strength of laminated structural PMCs. However, PMC laminates suffer from low interlaminar shear strength due to their weaker polymer-matrix. Minimising risks of delamination is of paramount importance towards improving the safety of PMC structures. Multi-scale composites that are reinforced by both continuous fibres and nano-particles were identified as a potential solution for improving toughness and reducing risks of delamination in PMCs.
An important challenge in the fabrication of multi-scale PMCs is to ensure that nano-particles are dispersed uniformly within the matrix. This is only achieved through minimal filtration of nano-particles during processing. The short resin flow lengths enabled by the resin film infusion (RFI) process make this process a prime candidate for the fabrication of multi-scale PMCs.
The main objective of this thesis is to validate the possibility of using out-of-autoclave RFI for fabricating multi-scale carbon fibre composites featuring epoxy resins modified with carbon nanotubes (CNTs). The work is accomplished in 5 phases.
In phase 1, preliminary work investigates the fabrication of PMCs with and without CNTs, using out-of-autoclave RFI. Results show that the types of reinforcement and matrix have strong effects on the porosity and interlaminar strength of PMCs. These results ushered the need for more thorough investigation and understanding of the RFI process, beyond what is available in the literature.
Phases 2 to 4 focus on understanding how the choices of materials and types of stacking configuration can affect parts made using RFI. Phase 2, the in-situ characterisation of resin saturation during RFI is performed. Results enable a detailed analysis of the way in which resin flows around and inside yarns. Phase 3 consists in the characterisation of void formation during RFI. Two types of voids are observed: flow-induced voids resulting from either the merging of resin flow fronts or the drainage from capillary action; and gas-induced voids resulting from resin volatiles going out of solution and remaining in the resin matrix. In this work, the greatest source of porosity was caused by volatiles. In phase 4, the distribution and filtration of CNTs during RFI processing is characterised. Results show that processing choices can limit filtration and that clustering of CNTs prevents a uniform dispersion of CNTs in PMCs.
Finally, the possibility of using RFI for making a multi-scale PMC demonstrator part is investigated. The work culminated with the successful fabrication of a delta-stringer panel.
This thesis makes several important contributions to the knowledge pertaining to multi-scale PMC processing and performance, and to RFI. Firstly, it provides a robust description of RFI processing beyond was it available in literature, through in-situ observations of resin flow and void formation. Secondly, it assesses the viability of RFI for producing multi-scale PMCs featuring CNTs. In-situ observations of RFI processing enabled the identification of mechanisms leading to a loss of CNT dispersion during processing, partly explaining the minimal improvements in the interlaminar properties of composites observed when adding CNTs to the matrix. Thirdly, the fabrication of a delta-stringer panel made of a multi-scale PMC was successful, making it the first validation of the scalability of out-of-autoclave RFI processing for manufacturing multi-scale PMCs. The work presented herein contributed to the dissemination of knowledge; one conference paper was presented at ICCM20 (20th International Conference on Composite Materials), and another was presented at CANCOM2017 (10th Canadian-International Conference on Composites), and one journal article written in collaboration with project partners was submitted to Composites Science and Technology.
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Nagesh, Mahesh. "Rotordynamic Design Analysis of a Squeeze Film Damper Test Rig." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin14915608677634.
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Lu, Kuan. "Optimization Of Sublimation Conditions for Surface Layer Matrix-assisted Laser Desorption Ionization Time of Flight Mass Spectrometry Imaging (SL-MALDI- Tof MSI) of Polymer Surfaces." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1524846943404769.
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Ouellet, Josiane. "Spectre des intramondes à l'ère du numérique : la réalité postmoderne dans des films mettant en scène le motif de la réalité virtuelle, notamment la trilogie «The Matrix, eXistenZ et Abre los Ojos». Suivi de: L'Empire des sortilèges (scénario)." Doctoral thesis, Université Laval, 2013. http://hdl.handle.net/20.500.11794/25973.
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Cette thèse cherche à démontrer l’hypothèse selon laquelle la réalité virtuelle au cinéma renvoie à la réalité de notre société placée sous le signe des technologies numériques et que les films qui y ont recours tiennent sur notre monde un discours postmodemiste s'apparentant à celui de Jean Baudrillard. Ainsi, j’y avance qu'un certain nombre d’enjeux sont contenus en puissance dans les technologies numériques et que, alors qu’elles sous tendent désormais l'ensemble de la société occidentale, il est normal que ces questions se retrouvent, de manière directe ou indirecte, dans les discours dont notre réalité fait l’objet. Concrètement, j'aborde la réalité virtuelle en tant que motif au sein d’un corpus de films la mettant en scène. En tant qu'unité de contenu stable, le motif possède un noyau de sens permanent et indépendant, que je tente de cerner en identifiant les thèmes reliés à la nature même du virtuel technoscientifique. Cela dit, le motif comporte aussi un certain potentiel, qui se réalise de diverses manières selon le cas. Je m’intéresse donc également à la façon dont les thèmes sont développés à travers les fables et les discours des différents récits filmiques étudiés. Autrement dit, je tente de relever le potentiel thématique du virtuel technoscientifique, pour ensuite vérifier comment il s’actualise dans les discours postmodemistes et dans des films mettant en scène le motif de la réalité virtuelle. Pour ce faire, je m’applique d’abord à définir les concepts utilisés (réalité, virtuel et réalitévirtuelle) et à établir une typologie du virtuel et de la réalité virtuelle ou de l’image. Au terme de cet exercice, je propose divers modèles du virtuel et des réalités virtuelles, que je regroupe ultimement dans un modèle général du virtuel dans la société postmodeme. Ce modèle est à la fois typologique et dynamique, dans le sens où il expose divers types devirtualité, mais aussi les relations que les éléments présentés entretiennent entre eux. Il mepermet de mettre en relief le nouveau statut du virtuel dans le contexte d’un monde envahi par les technologies numériques et d’appréhender les enjeux qui y sont rattachés. Surtout, ce modèle me permet de formuler diverses questions (par exemple : « À quel type de programme avons-nous affaire ? », « Quelle forme concrète prennent les interfaces dusystème de réalité virtuelle ? », « Quelle forme prend l'espace virtuel ? ») afin d'appréhender efficacement le motif de la réalité virtuelle dans les films de mon corpus. De plus, je me sers de ce modèle pour étayer mon hypothèse quant aux thèmes dont ce motif est porteur (par exemple, celui des apparences trompeuses). Après quoi, j'essaie de définir la postmodemité et les thèmes qui la traversent. Pour ce faire, je me penche sur différents écrits et, plus précisément, sur ceux de Baudrillard, auteur que j'ai privilégié non seulement en raison de son importance dans le champ des sciences humaines, mais également, parce qu'il parle de notre société en termes de réalité virtuelle. Mon objectif est alors de dégager les grandes lignes de ces discours tentant de cerner l'époque actuelle. Puis, j’observe qu’effectivement, certains thèmes qui les parcourent se rapprochent de ceux contenus en puissance dans le virtuel technoscientifique (par exemple, les thèmes des apparences trompeuses, du pouvoir, du destin et du libre-arbitre, de l’identité, des désirs). Ensuite, je procède à une analyse de contenu des films de mon corpus, soit la trilogie cinématographique The Matrix (Andy et Lana Wachowski, 1999, 2003), eXistenZ (David Cronenberg, 1999) ainsi qu'Abre los Ojos (Alejandro Amenábar, 1997) et son remake Vanilla Sky (Cameron Crowe, 2001). Plus concrètement, j’en relève les récits, les thèmes et les discours en fonction du motif de la réalité virtuelle. Pourquoi ces films ? Parce qu’ils mettent en scène un cas limite : une réalité virtuelle idéale. Ils risquent donc d’explorer un plus large spectre de possibles, quant aux problèmes et aux questions soulevés par le virtuel technoscientifique, que des films mettant en scène d’autres cas de figure. Cela fait, je remarque que les thèmes abordés s’apparentent à ceux rattachés aux technologies numériques et que les discours mis de l’avant s’inscrivent dans la foulée du postmodemisme, voire de la pensée de Baudrillard. Enfin, une analyse comparative de ces oeuvres et d’un corpus élargi d’une trentaine de films me permet d’étendre mes conclusions au motif de la réalité virtuelle au cinéma en général. Au terme de cette étude, il m'est possible de confirmer mon hypothèse de départ, tout en la nuançant. Dans un monde où les technologies numériques sont devenues omniprésentes, la réalité n'est plus ce qu'elle était, ce qui ne signifie pas qu'elle ait disparu, pour peu qu'elle ait jamais existé. Une certaine idée de la réalité s'est estompée, celle qui nous la présentait comme substantielle, rationnelle, mais le phénomène demeure, tandis que de nouvelles réalités voient le jour. Ainsi, la réalité se fait dorénavant « méta-réalité ». où se multiplient des « intramondes » (des notions que j'introduirai au final en guise de synthèse des observations contenues dans cette étude), entre lesquels le sujet doit apprendre à naviguer sans se perdre. En fait, la réalité virtuelle entraîne une mise en abyme de la réalité, faisant en sorte que cette dernière se donne désormais pour ce qu'elle est : une fiction. Ce procédé de mise à distance nous ouvre de nouvelles perspectives. A condition que la réalité virtuelle ne cherche pas à remplacer la réalité, auquel cas elle perd sa fonction. Or, la seule chose qui puisse nous prémunir contre une telle éventualité est notre conscience, notre mémoire, l’inscription de nos expériences au sein d’un itinéraire, d’un récit, d’une histoire propre à nous orienter dans ce monde déspatialisé. En seconde partie, je propose un scénario de science-fiction mettant en scène le motif de la réalité virtuelle. Je présente d’abord le projet dans ses grandes lignes (résumé, personnages, synopsis, traitement cinématographique et lieux). Puis, je détaille le scénario en tant que tel. Enfin, je livre ma création à une analyse comparable à celle à laquelle j’ai soumis les film sde mon corpus pour pouvoir la situer par rapport à l’ensemble et approfondir encore davantage ma réflexion. En fait, ma recherche théorique et mon travail de création se sont continuellement nourri l’un l’autre tout au long de ma démarche. Mes découvertes sur le virtuel m’ont permis d’en exploiter différentes dimensions dans mon scénario, tandis que les aventures de mon personnage m ’ont amenée à mieux comprendre certaines notions en les ancrant dans le concret.
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Tang, Andrew John. "Design and fabrication of polycrystalline material thin-film transistors for active matrix liquid-crystal display and static random access memory applications." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36035.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (leaves 81-82).
by Andrew John Tang.
M.S.
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Li, Han. "Analysis and Applications of Novel Optical Single - and Multi - Layer Structures." University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1450393885.
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Kroely, Laurent. "Process and material challenges in the high rate deposition of microcrystalline silicon thin films and solar cells by Matrix Distributed Electron Cyclotron Resonance plasma." Phd thesis, Ecole Polytechnique X, 2010. http://pastel.archives-ouvertes.fr/pastel-00550241.
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High deposition rates on large areas are industrial needs for mass production of microcrystalline silicon (μc-Si:H) solar cells. This doctoral work aims at exploring the usefulness of Matrix Distributed Electron Cyclotron Resonance (MDECR) plasmas to process the intrinsic layer of μc-Si:H p-i-n solar cells at high rates. With the high dissociation of silane achieved in MDECR plasmas, deposition rates as high as 6nm/s and 2.8nm/s have been demonstrated in our lab for amorphous and microcrystalline silicon respectively, without hydrogen dilution. This technique is also promising because it can be easily scaled up on large areas, just by extending the matrix of elementary microwave applicators. This subject was a unique opportunity to cover the whole chain of this field of research : A new MDECR reactor has been specially designed and assembled during this project. Its maintenance and its improvement have been important technical challenges : for example, the addition of a load-lock enabled us to lower the oxygen concentration in our films by a factor of 10. The impact of the deposition parameters (e.g. the ion energy, the substrate temperature, different gas mixtures, the microwave power) has been explored in extensive parametric studies in order to optimize the material quality. Great efforts have been invested in the characterization of the films. Our strategy has been to develop a wide range of diagnostics (ellipsometry, Raman spectroscopy, SIMS, FTIR, XRD, electrical characterizations etc.). Finally, p-i-n cells have been processed with the selected interesting materials. The successive successful improvements in the material quality (e.g. diffusion lengths of holes parallel to the substrate as high as 250 nm) did unfortunately not result in high efficiency solar cells. Their limited performance is in particular due to a very poor response in the red part of the spectrum resulting in low current densities. Consequently, the potential sources of limitation of the reactor, the material and the device have been studied : e.g. the presence of “cracks” prone to post-oxidation in the highly crystallized materials and the risk of deterioration of the ZnO substrate or of the p-doped layer by a too high process temperature or by hydrogen diffusing from the plasma.
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Russo, Florence. "Matériaux multicaloriques : Application à de nouveaux systèmes de refroidissement." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0097/document.
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Le domaine du refroidissement est en constante expansion, le système actuel est basé sur la compression/décompression des fluides. Face aux problèmes environnementaux et économiques que ce système présente (natures des fluides frigorigènes et leurs recyclages, nuisances sonores et vibratoires, réglementations contraignantes), de nouvelles solutions techniques alternatives émergent. Ainsi ce travail de thèse porte sur de nouveaux systèmes de refroidissement basés sur les effets électrocalorique et magnétocalorique, respectivement présents dans des films minces de polymère fluoré et dans des composites à matrice polymère et à charges magnétocaloriques. A travers des caractérisations physico-chimiques, électriques, électrocaloriques et magnétocaloriques ces travaux se proposent d’identifier l’origine de l’effet électrocalorique dans des films minces de terpolymère P(VDF-TrFE-CTFE) ferroélectrique relaxeur, mais également d’étudier l’influence de la dispersion des particules magnétocaloriques La(Fe,Si)H dans une matrice polymère de poly(propylène) sur le phénomène magnétocalorique. De plus, dans le cadre de cette thèse, un appareil de mesure directe de l’effet électrocalorique a été développé avec le Dr. Basso de l’INRIM de Turin. La comparaison avec la méthode de mesure indirecte permet d’aborder ce phénomène d’un point de vue thermodynamique afin de faire le point sur la validité des hypothèses thermodynamiques utilisées dans le cas d’un polymère ferroélectrique relaxeurThe cooling sector is in constant expansion, the current system is based on the compression/decompression of fluids. In front of environmental and economic problems of this system (nature of frigorigen fluids and their recycling, noise and vibration issues, restrictive regulations), new alternative technological solutions emerge. Thus this thesis provides new cooling systems based on the magnetocaloric and electrocaloric effects respectively present in thin films of fluoropolymer and composites with polymer matrix and magnetocaloric loads. Through physicochemical, electrical, electrocaloric and magnetocaloric characterizations, this work intends to identify the origin of electrocaloric effect in thin terpolymer films P(VDF-TrFE-CTFE) which is a ferroelectric relaxor, but also to study the influence of the magnetocaloric particles La(Fe,Si)H dispersion in a polymer matrix of poly(propylene) on the magnetocaloric phenomenon. In addition, as part of this thesis, a direct measurement device of the electrocaloric effect was developed with Dr. Basso from the INRIM of Turin. The comparison with the indirect measurement method comes up with this phenomenon from a thermodynamic point of view to take stock of the validity of thermodynamic assumptions used in the case of a ferroelectric polymer relaxor
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Helán, Radek. "Modelování a optimalizace komplexních vláknových difrakčních struktur." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-233450.
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The thesis discusses the fiber Bragg gratings simulations, analysis and design. In the present time, there are several methods to simulate fiber gratings response based on the stated parameters that define their dimensions and material features. However, this work deals with a different issue, that is the synthesis of the input parameters for demanded spectral responses. The main aim of the work is to achieve a synthesis method that would help to discover parameters describing advanced grating structure, based on the required spectral reflectivity. The basic demand for the parameter synthesis is an achievement of the real values in terms of the consequent production of the suggested structure. The described synthesis method considers advanced fiber grating structure as a structure of several uniform grating sections. The input parameters are estimated in steps, using the well-known direct methods in order to obtain grating responses and feedback to establish the parameters changes. The principle methods involve establishment of initial input parameter values and necessary subsequent algorithm leading to optimize the required spectral response. The initial values are calculated by a simplified model based on the coupled theory equations that are handled for the periodic disturbances in cylindrical waveguide. The following optimization uses the multiple thin film stack and transfer matrix methods. The properties of grating structure spectral reflectivity are step by step calculated while using these direct methods. Input parameters are established in the next several steps. Establishment of input parameters is done subsequently, based on the demanded and calculated output spectral reflectivity properties. Optimizing process is limited by possibilities of the grating manufacture technology. It is possible to assemble arbitrary fiber grating structure taking in term the demanded spectral response. Nevertheless, the calculated input parameters are real for the following manufacture. This method could be used to design optical band stop filter, high-pass and low-pass filters or filters for special applications.
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Popel, Aleksej. "The effect of radiation damage by fission fragments on the structural stability and dissolution of the UO2 fuel matrix." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/265103.
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The aim of this work was to study the separate effect of fission fragment damage on the structural integrity and matrix dissolution of uranium dioxide in water. Radiation damage similar to fission damage was created by irradiating bulk undoped and doped ‘SIMFUEL’ disks of UO2, undoped bulk CeO2 and thin films of UO2 and CeO2 with high energy Xe and U ions. The UO2 thin films, with thicknesses in the range of 90 – 150 nm, were deposited onto (001), (110) and (111) orientations of single crystal LSAT (Al10La3O51Sr14Ta7) and YSZ (Yttria-Stabilised Zirconia) substrates. The CeO2 thin films were deposited onto single crystal silicon (001) substrates. Part of the bulk UO2 and CeO2 samples, the thin films of UO2 on the LSAT substrates and the thin films of CeO2 were irradiated with 92 MeV 129Xe23+ ions to a fluence of 4.8 × 1015 ions/cm2 to simulate the damage produced by fission fragments in uranium dioxide nuclear fuel. Part of the bulk UO2 and CeO2 samples and the thin films of UO2 on the YSZ substrates were irradiated with 110 MeV 238U31+ ions to a fluence of 5 × 1010, 5 × 1011 and 5 × 1012 ions/cm2 to study the accumulation of the damage induced. The irradiated and unirradiated samples were studied using scanning electron microscopy (SEM), focused ion beam (FIB), atomic force microscopy (AFM), energy dispersive X-ray (EDX) spectroscopy, electron probe microanalysis (EPMA), X-ray diffraction (XRD), electron backscatter diffraction (EBSD), secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) techniques to characterise the as-produced samples and assess the effects of the ion irradiations. Dissolution experiments were conducted to assess the effect of the Xe ion irradiation on the dissolution of the thin film UO2 samples on the LSAT substrates and the bulk and thin film CeO2 samples. The solutions obtained from the leaching of the irradiated and unirradiated samples were analysed using inductively coupled plasma mass spectrometry (ICP-MS). XRD studies of the bulk UO2 samples showed that the ion irradiations resulted in an increased lattice parameter, microstrain and decreased crystallite size, as expected. The irradiated UO2 thin films on the LSAT substrates underwent significant microstructural and crystallographic rearrangements. It was shown that by irradiating thin films of UO2 with high energy, high fluence ions, it is possible to produce a structure that is similar to a thin slice through the high burn-up structure. It is expected that the ion irradiation induced chemical mixing of the UO2 films with the substrate elements (La, Sr, Al, Ta). As a result, a material similar to a doped SIMFUEL with induced radiation damage was produced.
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Yang, Jing. "Phosphonium ionic liquids : Versatile nanostructuration and interfacial agents for poly(vinylidene fluoride-chlorotrifluoroethylene)." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI072/document.
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Ce travail de thèse porte sur la compréhension du rôle polyvalent des liquides ioniques (LIs) phosphonium comme agents de nanostructuration et interfaciaux pour la matrice polymère fluorée poly(fluorure de vinylidène-chlorotrifluoroéthylène) (P(VDF-CTFE)). Dans un premier temps, deux LIs phosphonium avec des fonctionnalités différentes générant un encombrement stérique et des fonctions dipolaire additionnelles sont tout d'abord incorporés dans la matrice P(VDF-CTFE) pour préparer des films de polymère additives. La structure de la phase cristalline, la morphologie issue de la dispersion et le comportement de cristallisation sont finement caractérisés dans le but de fournir une compréhension fuie et complète du rôle joué par le LI sur la nanostructuration. Dans un second temps, le rôle d’agent interfacial du LI est étudié avec un LI phosphonium fluoré comprenant un cation combinant trois phényles et une chaîne fluorée courte.Ce LI est utilise pour modifier la surface de l'oxyde de graphène (GO) et de l'oxyde de graphène réduit (rGO) afin de rendre ces nanocharges fonctionnelles et les incorporer dans la matrice P(VDF-CTFE). Ainsi, des films composites de P(VDF-CTFE)/graphène avec différentes teneurs en nanocharges sont préparés et une caractérisation fuie de la structure et des propriétés est entreprise afin de mieux comprendre les mécanisme d’interaction interfaciale et leurs influences sur les films composites, tels que la structure de la phase cristalline, le comportement de cristallisation, la relaxation des chaînes, la morphologie et les propriétés diélectriques finalesThis thesis work deals with an understanding of the versatile roles of phosphonium ionic liquids (ILs) as nanostructuration and interfacial agents for the fluorinated polymer matrix, i.e.,poly(vinylidene fluoride-chlorotrifluoroethylene) (P(VDF-CTFE)). In this context, two phosphonium ILs with different functionalities in steric hindrance and extra dipolar groups are firstly incorporated in P(VDF-CTFE) matrix to prepare polymer films. The crystalline phase structure, dispersion morphology and crystallization behavior are finely characterized with the goal of providing a full and deep understanding of the versatile and tunable nanostructuration effect of phosphonium ILs. Subsequently, in order to elucidate the mechanism of interfacial influence of IL, a fluorinated phosphonium IL with a cation structure combining three phenyls and a short fluorinated chain is added on the surface of graphene oxide (GO) and reduced graphene oxide (rGO), making them as functional nanofillers to be incorporated into P(VDF-CTFE) matrix. Thus,P(VDF-CTFE)/graphene composite films with different filler contents are prepared in order to investigate the mechanism of interfacial interaction and its influence on the composite films, such as crystalline phase structure, crystallization behavior, chain segmental relaxation behavior, dispersion morphology and the final dielectric properties
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Baronnier, Justine. "Encapsulation de nanocristaux II-VI dans une matrice semiconductrice de pérovskite hybride d’halogénure de plomb en vue de la création d’un dispositif de contrôle du clignotement." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1297.
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Dans le but de concevoir un dispositif de contrôle du clignotement des nanocristaux, il était nécessaire de créer un composite à l'état solide pouvant s'intégrer dans ce dispositif. Nous avons donc encapsulé des boites quantiques (BQs) à base de cadmium dans une matrice cristalline de pérovskite hybride de bromure de plomb. Ce manuscrit retrace l'ensemble des étapes qui ont été validé pour atteindre la création de ce nouveau composite. Nous avons développé avec succès une synthèse de BQs résistantes à l'encapsulation dans une matrice ionique mais également un échange de ligands inorganiques qui nous a permis d'intégrer de manière efficace les nanocristaux au sein de leur matrice en conservant leurs propriétés de luminescence. Après encapsulation, nous avons pu mettre en avant des preuves montrant une encapsulation efficace et un couplage entre les BQs et la matrice. Ces deux critères sont favorables à l'utilisation de ce composite dans le dispositif de contrôle. Ce dispositif consiste in fine à suivre optiquement la luminescence des BQs et à appliquer un champ électrique pour extraire et évacuer les charges en excès, qui sont à l'origine de l'état non émissif. Le développement de cette partie nous permettra dans le futur d'étudier le phénomène de clignotement mais surtout d'obtenir une source de photons uniques stable et à la demandeTo construct a device for controlling the blinking of nanocrystals, it was necessary to create a solid-state active material that can be integrated in such an apparatus. To this end, we have encapsulated cadmium-based quantum dots (QDs) in a crystalline matrix of a hybrid lead-bromide perovskite. This manuscript describes all the steps that have been undertaken to achieve the creation of this new composite. We have developed a synthesis of QDs that are resistant to encapsulation in an ionic matrix by means of an organic-inorganic ligand exchange that allowed us to integrate nanocrystals into the matrix while conserving their luminescence properties. We were thus able to document efficient encapsulation and a coupling between the QDs and the matrix. These two characteristics are favorable for using this composite in a control device which ultimately aims at optically following the luminescence of the BQs and applying an electric field to extract and evacuate the excess charges responsible for the nonemissive state. The successful completion of this step will enable us in the future to study the phenomenon of blinking and, more importantly, to construct a stable on-demand single-photon source
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El-Zein, Ahmad A. "Sparse matrix computations using the intelligent file store." Thesis, University of Essex, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305948.
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Canguçu, Cristiano. "A construção narrativa e plástica do filme Matrix." reponame:Repositório Institucional da UFBA, 2011. http://www.repositorio.ufba.br/ri/handle/ri/1162.
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Esta dissertação analisa as estratégias narrativas e a composição cinematográfica do filme de ficção científica Matrix, sob a perspectiva teórico-analítica Poética do Filme e os conceitos narratológicos do Neoformalismo. Investigam-se os recursos e as estratégias empregadas por esse filme para os seus efeitos próprios; especificamente, examinam-se a narrativa enigmática, a construção do universo ficcional e a poética do filme de ação que, juntos, caracterizam esse filme.
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Escorihuela, Roca Sara. "Novel gas-separation membranes for intensified catalytic reactors." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/121139.
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[ES] La presente tesis doctoral se centra en el desarrollo de nuevas membranas de separación de gases, así como su empleo in-situ en reactores catalíticos de membrana para la intensificación de procesos. Para este propósito, se han sintetizado varios materiales, como polímeros para la fabricación de membranas, catalizadores tanto para la metanación del CO2 como para la reacción de síntesis de Fischer-Tropsch, y diversas partículas inorgánicas nanométricas para su uso en membranas de matriz mixta. En lo referente a la fabricación de las membranas, la tesis aborda principalmente dos tipos: orgánicas e inorgánicas. Con respecto a las membranas orgánicas, se han considerado diferentes materiales poliméricos, tanto para la capa selectiva de la membrana, así como soporte de la misma. Se ha trabajado con poliimidas, puesto que son materiales con temperaturas de transición vítrea muy alta, para su posterior uso en reacciones industriales que tienen lugar entre 250-300 ºC. Para conseguir membranas muy permeables, manteniendo una buena selectividad, es necesario obtener capas selectivas de menos de una micra. Usando como material de soporte otro tipo de polímero, no es necesario estudiar la compatibilidad entre ellos, siendo menos compleja la obtención de capas finas. En cambio, si el soporte es de tipo inorgánico, un exhaustivo estudio de la relación entre la concentración y la viscosidad de la solución polimérica es altamente necesario. Diversas partículas inorgánicas nanométricas se estudiaron para favorecer la permeación de agua a través de los materiales poliméricos. En segundo lugar, en cuanto a membranas inorgánicas, se realizó la funcionalización de una membrana de paladio para favorecer la permeación de hidrógeno y evitar así la contaminación por monóxido de carbono. El motivo por el cual se dopó con otro metal la capa selectiva de la membrana metálica fue para poder emplearla en un reactor de Fischer-Tropsch. Con relación al diseño y fabricación de los reactores, durante esta tesis, se desarrolló el prototipo de un microreactor para la metanación de CO2, donde una membrana polimérica de capa fina selectiva al agua se integró para evitar la desactivación del catalizador, y a su vez desplazar el equilibrio y aumentar la conversión de CO2. Por otro lado, se rediseñó un reactor de Fischer-Tropsch para poder introducir una membrana metálica selectiva a hidrogeno y poder inyectarlo de manera controlada. De esta manera, y siguiendo estudios previos, el objetivo fue mejorar la selectividad a los productos deseados mediante el hidrocraqueo y la hidroisomerización de olefinas y parafinas con la ayuda de la alta presión parcial de hidrógeno.[CAT] La present tesi doctoral es centra en el desenvolupament de noves membranes de separació de gasos, així com el seu ús in-situ en reactors catalítics de membrana per a la intensificació de processos. Per a aquest propòsit, s'han sintetitzat diversos materials, com a polímers per a la fabricació de membranes, catalitzadors tant per a la metanació del CO2 com per a la reacció de síntesi de Fischer-Tropsch, i diverses partícules inorgàniques nanomètriques per al seu ús en membranes de matriu mixta. Referent a la fabricació de les membranes, la tesi aborda principalment dos tipus: orgàniques i inorgàniques. Respecte a les membranes orgàniques, diferents materials polimèrics s'ha considerat com a candidats prometedors, tant per a la capa selectiva de la membrana, així com com a suport d'aquesta. S'ha treballat amb poliimides, ja que són materials amb temperatures de transició vítria molt alta, per al seu posterior ús en reaccions industrials que tenen lloc entre 250-300 °C. Per a aconseguir membranes molt permeables, mantenint una bona selectivitat, és necessari obtindre capes selectives de menys d'una micra. Emprant com a material de suport altre tipus de polímer, no és necessari estudiar la compatibilitat entre ells, sent menys complexa l'obtenció de capes fines. En canvi, si el suport és de tipus inorgànic, un exhaustiu estudi de la relació entre la concentració i la viscositat de la solució polimèrica és altament necessari. Diverses partícules inorgàniques nanomètriques es van estudiar per a afavorir la permeació d'aigua a través dels materials polimèrics. En segon lloc, quant a membranes inorgàniques, es va realitzar la funcionalització d'una membrana de pal¿ladi per a afavorir la permeació d'hidrogen i evitar la contaminació per monòxid de carboni. El motiu pel qual es va dopar amb un altre metall la capa selectiva de la membrana metàl¿lica va ser per a poder emprar-la en un reactor de Fischer-Tropsch. En relació amb el disseny i fabricació dels reactors, durant aquesta tesi, es va desenvolupar el prototip d'un microreactor per a la metanació de CO2, on una membrana polimèrica de capa fina selectiva a l'aigua es va integrar per a així evitar la desactivació del catalitzador i al seu torn desplaçar l'equilibri i augmentar la conversió de CO2. D'altra banda, un reactor de Fischer-Tropsch va ser redissenyat per a poder introduir una membrana metàl¿lica selectiva a l'hidrogen i poder injectar-lo de manera controlada. D'aquesta manera, i seguint estudis previs, el objectiu va ser millorar la selectivitat als productes desitjats mitjançant el hidrocraqueix i la hidroisomerització d'olefines i parafines amb l'ajuda de l'alta pressió parcial d'hidrogen.
[EN] The present thesis is focused on the development of new gas-separation membranes, as well as their in-situ integration on catalytic membrane reactors for process intensification. For this purpose, several materials have been synthesized such as polymers for membrane manufacture, catalysts for CO2 methanation and Fischer-Tropsch synthesis reaction, and inorganic materials in form of nanometer-sized particles for their use in mixed matrix membranes. Regarding membranes manufacture, this thesis deals mainly with two types: organic and inorganic. With regards to the organic membranes, different polymeric materials have been considered as promising candidates, both for the selective layer of the membrane, as well as a support thereof. Polyimides have been selected since they are materials with very high glass transition temperatures, in order to be used in industrial reactions which take place at temperatures around 250-300 ºC. To obtain highly permeable membranes, while maintaining a good selectivity, it is necessary to develop selective layers of less than one micron. Using another type of polymer as support material, it is not necessary to study the compatibility between membrane and support. On the other hand, if the support is inorganic, an exhaustive study of the relation between the concentration and the viscosity of the polymer solution is highly necessary. In addition, various inorganic particles were studied to favor the permeation of water through polymeric materials. Secondly, as regards to inorganic membranes, the functionalization of a palladium membrane to favor the permeation of hydrogen and avoid carbon monoxide contamination was carried out. The membrane selective layer was doped with another metal in order to be used in a Fischer-Tropsch reactor. Regarding the design and manufacture of the reactors used during this thesis, a prototype of a microreactor for CO2 methanation was carried out, where a thin-film polymer membrane selective to water was integrated to avoid the deactivation of the catalyst and to displace the equilibrium and increase the CO2 conversion. On the other hand, a Fischer-Tropsch reactor was redesigned to introduce a hydrogen-selective metal membrane and to be able to inject it in a controlled manner. In this way, and following previous studies, the aim is to enhance the selectivity to the target products by hydrocracking and hydroisomerization the olefins and paraffins assisted by the presence of an elevated partial pressure of hydrogen.
I would like to acknowledge the Spanish Government, for funding my research with the Severo Ochoa scholarship.
Escorihuela Roca, S. (2019). Novel gas-separation membranes for intensified catalytic reactors [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/121139
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Sroan, Baninder Singh. "Mechanism of gas cell stability in bread making." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/338.
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MONTÓRIO, JÚNIOR Italo Alves. "Alteração da composição da Matriz Elétrica a fim de mitigar a emissão de gases de efeito estufa." Universidade do Oeste Paulista, 2018. http://bdtd.unoeste.br:8080/jspui/handle/jspui/1111.
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Humanity goes through a period of great transformations. Anthropic activity, mainly in recent years, has been substantially modified the terrestrial environment. Practices which damage the Earth system, such as Greenhouse Gas (GHG) emissions, can compromise the terrestrial life. The utilization of non-renewable sources has promoted a significant increase in air pollutant emissions. It supposes that the population, now estimated at more than seven billion, is expected to reach around 10 billion people by 2050 and the global economy to triple in this period, conditions that will lead to large increases in global demand for energy. Due to this continuous and progressive increase in energy consumption, it will be necessary to generate more electricity. Therefore, there is a need of an intense analysis of the anthropic practiced activities. The hypothesis of this work is presented as the alteration of the Electric Matrix composition in order to mitigate the Greenhouse Gas emission. The present work has as objectives to study the projection of GHG emission in the Brazilian Electrical Matrix by the year 2050 using the "Calculadora Brasil 2050" application, to perform a case study of the alteration in the Electric Matrix composition of energy consumed by Instituto Federal de São Paulo, Presidente Epitácio Campus, through a photovoltaic micro power plant and the an energy efficiency program, and finally, to study the global Electrical Matrix composition and its implications on environmental issues through qualitative and quantitative documentary research of applied nature. The Brazilian Electrical Matrix is expected to have an increment in the use of photovoltaic solar energy and in energy efficiency to maintain GHG emissions in the year of 2050 at the same current levels. There was an 8.30% reduction in the consumption of the Electrical Energy (EE) acquired from the distribution network with the installation of the photovoltaic micro power plant, and it occurred a reduction of 51% in the EE consumption for lighting with the implemented energy efficiency program. The institution stopped using 1,386.78 KWh per month from non-renewable sources, which is equivalent to a reduction of 31.8%, proving the alteration in the Electric Matrix consumed by the campus. In the world, countries have a distinct relation between the use of renewable and non-renewable sources for EE generation, implicating in a possibility of classification of these countries in relation to environmental issues by the Environmental Contribution Rate (ECR). The Environmental Balance Time (EBaT) of photovoltaic panels is related to the ECR and the Energy Pay Back Time (EPBT) of the system.
A humanidade passa por um período de grandes transformações. A atividade antrópica, principalmente nos últimos anos, tem modificado substancialmente o ambiente terrestre. Práticas que lesionam o sistema do planeta Terra, como as emissões de gases de efeito estufa, podem comprometer a vida terrestre. A utilização de fontes não renováveis promoveu um acréscimo significativo nas emissões de poluentes atmosféricos. Supõe-se que a população, hoje estimada em mais de sete bilhões, chegue ao redor de dez bilhões de indivíduos em 2050 e que a economia global triplique neste período, condições que levarão a grandes aumentos na demanda global por energia. Devido a este aumento contínuo e progressivo do consumo de energia, será necessário gerar mais eletricidade. Portanto, há a necessidade de uma profunda análise das atividades antrópicas praticadas. A hipótese deste trabalho apresenta-se como a alteração da composição da Matriz Elétrica a fim de mitigar a emissão de gases de efeito estufa. O presente trabalho tem como objetivos estudar a projeção da emissão de GEE na Matriz Elétrica brasileira até o ano de 2050 utilizando o aplicativo “Calculadora Brasil 2050”, realizar um estudo de caso da alteração da composição da Matriz Elétrica da energia consumida pelo Instituto Federal de São Paulo Câmpus Presidente Epitácio por meio de uma micro usina fotovoltaica e de um programa de eficiência energética e, finalmente, estudar a composição da Matriz Elétrica mundial e suas implicações nas questões ambientais por meio de uma pesquisa documental quali quantitativa e de natureza aplicada. A Matriz Elétrica brasileira deverá ter um incremento na utilização da energia solar fotovoltaica e em eficiência energética para manter as emissões de GEE no ano de 2050 nos mesmos níveis atuais. Com a instalação da micro usina fotovoltaica ocorreu uma redução 8,30% no consumo de Energia Elétrica (EE) adquirida da rede de distribuição e com o programa de eficiência energética implantado, ocorreu uma redução de 51% do consumo de EE para a iluminação. A instituição deixou de utilizar, mensalmente, 1.386,78 KWh provenientes de fontes não renováveis, o que equivale a uma redução de 31,8%, comprovando a alteração da Matriz Elétrica consumida pelo câmpus. No mundo, os países possuem uma relação distinta entre a utilização de fontes renováveis e não renováveis para a geração de EE, implicando em uma possibilidade de classificação destes países em relação às questões ambientais pela “Environmental Contribution Tax” (ECR). O “Environmental Balance Time” (EBaT) dos painéis fotovoltaicos está relacionado com o ECR e com o “Energy Pay Back Time” (EPBT) do sistema.
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Alwardt, Cory M. "Effects of Age and Immune Dysfunction on the Cardiac Extracellular Matrix and Diastolic Function." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1128%5F1%5Fm.pdf&type=application/pdf.
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Hays, Allison Marie. "Arsenic Exposure: Effects on Oxidative Stress, Gene Regulation and the Extracellular Matrix in the Lung." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1403%5F1%5Fm.pdf&type=application/pdf.
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Söderhäll, Marie. "Nygnosticism i Matrixtrilogin : en studie av vårt gnostiska arv i dagens mediala berättande." Thesis, University of Gävle, Ämnesavdelningen för religionsvetenskap, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-4379.
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Uppsatsen består framför allt av en jämförelse mellan de nygnostiska inslagen i filmerna Matrix, Matrix Reloaded, Matrix Revolutions samt Animatrix och den antika versionen av gnosticism. Jag har speciellt använt mig av Valentinus kosmogoni hämtad ur H. Jonas bok ”The Gnosic Religion”, för denna jämförelse. Hela arbetet sträcker sig dock över flera områden och ämnen som historia, genus, sociala och politiska förändringar, våra media och existentiella spörsmål i västvärlden idag mm.
Eftersom gnosticismen delvis uppstod och formades i nära förhållande till kristendomen, samt levde vidare under ytan av det etablerade fram till nyligen, finns det flera paralleller mellan dåtid och nutid. Idag är ett tydligt tecken på detta New Age, det samlingsbegrepp som rymmer så mycket men som likt gnosticismen delar på många föreställningar. T.ex. människans vilja till förmåga bortanför och utöver materien/kroppen, hennes eget inre gudomliggörande och behovet av en transcendent messias mm. Profana likheter kan vara pessimism, nihilism, känslan av en konstgjord och overklig verklighet, verklighetsflykt mm.
På ett annat plan handlar uppsatsen om människans mytologiserade/andliga psykologi, dels om Jungs arketypiska psykologi och dels om nyandlig mystik. Hur de kliver in och tar över tomrummet i den traditionellt vetenskapliga och rationella värld vi ”mytlösa” lever i. Den religiösa mystiken var en allmän realitet förr i tiden, men blev s.a.s. bortrationaliserad i upplysningens och senare protestantismens era. Människans belägenhet i den tekniskt avancerade världen har förändrat mycket, också hennes psyke. Bröderna Wachowskis filmverk visar också tydligt på den gnostiska versionen av uppdelningen mellan omedvetna, medvetna och upplysta. Att ”felet” med människan är hennes okunskap om den yttre verkligheten, och att räddningen ligger i ett introvert sökande efter sanningen. Uppsatsens helhet rör sig alltså både i det yttre och det inre, likt Matrixtrilogin och ny/gnosticismen, över tid och rum samt mellan olika tekniska mediala medel.
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Alshali, Ruwaida. "Characterization of bulk-fill and conventional light-cured resin-composites in terms of composition and polymer matrix properties." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/characterization-of-bulkfill-and-conventional-lightcured-resincomposites-in-terms-of-composition-and-polymer-matrix-properties(d85d7616-35e5-4a04-a5b3-20458de1e11d).html.
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Resin-composites have been used in dentistry as direct restorative materials for over fifty years ago, and meanwhile their properties have been substantially improved. Recently a new class of light-cured resin-composites known as 'bulk-fill' materials has been introduced, and has increased the practical application of resin-composites in comparison to conventional incrementally applied materials. The aim of the present research was to assess bulk-fill resin-composites in comparison to conventional materials with respect to their composition, polymeric structure properties and hygroscopic behaviour in oral and food simulating substances. A variety of bulk-fill and conventional resin-composites were tested in this study. Monomer composition of materials has been qualitatively and quantitatively determined using high performance liquid chromatography and mass spectroscopy, and their degree of conversion assessed using Fourier transform infrared spectroscopy. It was found that the degree of conversion of the bulk-fill resin-composites was generally comparable to that of conventional materials and appeared to be governed by the type and quantity of monomers comprising the resin matrix. To evaluate the cross-link density of the polymer matrix, the extent of post-irradiation hardness development, chemical softening, and thermal stability were assessed using microhardness and thermogravimetric analysis. Materials showed variable results and it was suggested that two networks were present in the polymerized resin matrix, a primary network forming immediately after curing followed by a secondary network. The secondary network seemed to have poor cross-link density with low resistance to the degradative effects of solvents. Monomer elution from cured materials was assessed using High performance liquid chromatography over three months' storage in three different media. Elution from bulk-fill resin-composites was found to be comparable to that of conventional materials, despite their increased incremental thickness, with remarkably minimal elution taking place from two bulk-fill materials examined. Monomer elution was shown to be highly dependent on the hydrophobicity of the base monomers and the network characteristics of the resin-matrix. UDMA-BisEMA based systems appeared to be more vulnerable in organic solutions than BisGMA and BisGMA-BisEMA based systems in terms of monomer elution. Sorption and solubility were assessed after one years' storage in water and artificial saliva. Water sorption and solubility of resin-composites were material-dependent and highly affected by the filler loading and initial degree of conversion of the polymeric matrix. BisEMA and UDMA-BisEMA based polymer networks appeared to be more hydrophobic and resistant to sorption and solubility than BisGMA based systems in water based media. The bulk-fill and conventional resin-composites tested were considered stable in the long-term water storage, with the exception of one conventional flowable material.
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Castiglioni, Andrea <1984>. "Effetti della viscoelasticità sulla misura dell’energia di adesione tra film di polietilene." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6766/.
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Lo stretch film è una diffusa applicazione per imballaggio dei film in polietilene (PE), utilizzato per proteggere diversi prodotti di vari dimensioni e pesi. Una caratteristica fondamentale del film è la sua proprietà adesiva in virtù della quale il film può essere facilmente chiuso su se stesso.
Tipicamente vengono scelti gradi lineari a bassa densità (LLDPE) con valori relativamente bassi di densità a causa delle loro buone prestazioni. Il mercato basa la scelta del materiale adesivo per tentativi piuttosto che in base alla conoscenza delle caratteristiche strutturali ottimali per l’applicazione.
Come per i pressure sensitive adhesives, le proprietà adesive di film stretch in PE possono essere misurati mediante "peel testing". Esistono molti metodi standard internazionali ma i risultati di tali prove sono fortemente dipendenti dalla geometria di prova, sulla possibile deformazione plastica che si verificano nel peel arm(s), e la velocità e temperatura.
Lo scopo del presente lavoro è quello di misurare l'energia di adesione Gc di film stretch di PE, su se stessi e su substrati diversi, sfruttando l'interpretazione della meccanica della frattura per tener conto dell'elevata flessibilità e deformabilità di tali film.
Quindi, la dipendenza velocità/temperatura di Gc sarà studiata con riferimento diretto al comportamento viscoelastico lineare dei materiali utilizzati negli strati adesivi, per esplorare le relazioni struttura-proprietà che possono mettere in luce i meccanismi molecolari coinvolti nei processi di adesione e distacco. Nella presente caso, l’adesivo non è direttamente disponibile come materiale separato che può essere messo tra due superfici di prova e misurato per la determinazione delle sue proprietà. Il presupposto principale è che una parte, o fase, della complessa struttura semi-cristallina del PE possa funzionare come adesivo, e un importante risultato di questo studio può essere una migliore identificazione e caratterizzazione di questo "fase adesiva".Stretch wrap is a widespread packaging application of Polyethylene (PE) films, used to held together and protect many possible products of varying number, sizes and weights. A key feature of stretch wrap films is their adhesive property, by virtue of which the wrap can be easily closed onto itself. Typically, Linear Low Density grades (LLDPEs) with comparatively low density values are chosen, because of their known good adhesive (“cling”) properties. The market relies on trial and error for the choice of the adhesive material rather than choose upon known optimal structure’s properties tailored for the application. As for pressure sensitive adhesives, the adhesive properties of PE stretch films can be measured by “peel testing”. Many international standard methods exist, and the results of such tests are strongly dependent on test geometry, on the possible plastic deformation occurring in the peel arm(s), and on peeling rate and temperature. The aim of the present work is to measure the adhesive energy Gc of PE stretch films onto themselves and on different substrates, by taking advantage of the fracture mechanics approach to account for the high flexibility and deformability of these films. The measured rate/temperature dependence of Gc will be studied with reference to the linear viscoelastic behaviour of the materials used in the adhesive layers, in order to explore the structure-property relationships which could enlighten the molecular mechanisms involved in the adhesion and detachment processes. In the present case, the “adhesive” is not available as a separate material which could be tested and sampled for determination of its properties. The main assumption is that some part, or phase, of the complex semi-crystalline polyethylene material works as an adhesive, and an important outcome of this study can be a better identification and characterization of this “adhesive phase”.
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Morales-Vidal, Marta. "High performance thin film organic lasers for sensing applications." Doctoral thesis, Universidad de Alicante, 2015. http://hdl.handle.net/10045/63751.
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Yousef, Yaser. "Routage pour la gestion de l'énergie dans les réseaux de capteurs sans fil." Phd thesis, Université de Haute Alsace - Mulhouse, 2010. http://tel.archives-ouvertes.fr/tel-00590407.
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Avec l'émergence des nouvelles technologies, les communications sans fil n'ont cessé de croître afin de permettre aux utilisateurs un accès à l'information et aux services électroniques, et ceci indépendamment de leur position géographique. Les réseaux sans fil ont aussi trouvé leur place pour des applications spécifiques telles que les transmissions radio utilisées pour l'interconnexion de capteurs. Ce type de réseau peut être considéré comme un sous-ensemble des réseaux ad hoc. Des contraintes spécifiques s'appliquent alors aux utilisateurs de ces réseaux, telles que la difficulté d'accès pour la maintenance, les problèmes liés à la miniaturisation et au nombre élevé de capteurs. L'objectif de cette thèse est d'étudier les contraintes énergétiques liées à l'utilisation des batteries à capacité limitée pour l'alimentation des capteurs. Pour atteindre cet objectif, nous avons proposé de représenter les réseaux de capteurs à travers une image à échelle de gris : les zones claires correspondant aux zones riches en énergie, alors que les zones sombres représentent des régions avec une capacité énergétique faible. Des filtres issus du monde de traitement d'image sont alors appliqués à cette image représentant l'énergie. Ainsi, nous proposons des filtres de convolution de type Sobel ou de type filtre moyen pour nos algorithmes de routage et nous construisons une matrice énergétique pour chaque capteur. Cette matrice est alors utilisée avec le produit de convolution pour guider le routage. Les différents algorithmes proposés font ensuite l'objet de simulations avec le simulateur de réseaux OMNeT++.
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Cheng, Lu. "Concentric layout, a new scientific data layout for matrix data set in Hadoop file system." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4545.
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The data generated by scientific simulation, sensor, monitor or optical telescope has increased with dramatic speed. In order to analyze the raw data speed and space efficiently, data pre-process operation is needed to achieve better performance in data analysis phase. Current research shows an increasing tread of adopting MapReduce framework for large scale data processing. However, the data access patterns which generally applied to scientific data set are not supported by current MapReduce framework directly. The gap between the requirement from analytics application and the property of MapReduce framework motivates us to provide support for these data access patterns in MapReduce framework. In our work, we studied the data access patterns in matrix files and proposed a new concentric data layout solution to facilitate matrix data access and analysis in MapReduce framework. Concentric data layout is a data layout which maintains the dimensional property in chunk level. Contrary to the continuous data layout which adopted in current Hadoop framework by default, concentric data layout stores the data from the same sub-matrix into one chunk. This matches well with the matrix operations like computation. The concentric data layout preprocesses the data beforehand, and optimizes the afterward run of MapReduce application. The experiments indicate that the concentric data layout improves the overall performance, reduces the execution time by 38% when the file size is 16 GB, also it relieves the data overhead phenomenon and increases the effective data retrieval rate by 32% on average.ID: 029051151; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.)--University of Central Florida, 2010.; Includes bibliographical references (p. 56-58).
M.S.
Masters
Department of Electrical Engineering and Computer Science
Engineering
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Lavoie, Jean-Michel. "Mammalian cell culture on poly (dimethyl siloxane) functionalized for covalent immobilization of extracellular matrix-derived proteins." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116017.
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In vitro cell culture is an essential part of many cell and tissue engineering approaches. In particular, monolayer culture of mammalian cells is a key tool for applications such as cell therapy. Novel bioreactors like the Cellerator(TM) allow for expansion of cell populations on mechanically stimulated surfaces coated with proteins. This thesis constitutes a preliminary study which focused on cell-matrix interactions in the absence of stretch. The aim was to establish standard protocols for protein coating on poly (dimethyl siloxane) (PDMS) and for measuring cell proliferation. Specifically, the proliferation of rat pulmonary artery vascular smooth muscle (PAC1) cells on type I collagen and soluble fibronectin was studied. Growth curves were obtained and the doubling time for subconfluent cultures was computed. Although cell-matrix interactions do not enhance proliferation of PAC1 cells, it was found that a preliminary sulphuric acid treatment is necessary to yield a well-behaved culture.
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Del, Campo Menoyo Javier. "Compatibilisation of polyimide-silica ceramers and interfacial interactions with carbon fibres in high-temperature matrix composites." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/27080.
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When the inorganic domain sizes in a composite are reduced to a level such that a "molecular composite" is formed, the hybrid materials are commonly referred to as "ceramers". Hybrid materials span from inorganically modified organic polymers to inorganic g1asses slightly modified by organic polymers. The incorporation of an inorganic phase into an organic polymer is done almost exclusively by the "sol-gel" process.
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Moroz, Pavel. "A Novel Approach for the Fabrication of All-Inorganic Nanocrystal Solids: Semiconductor Matrix Encapsulated Nanocrystal Arrays." Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1435324105.
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Perani, Martina <1987>. "Nanocrystalline Silicon Based Films for Renewable Energy Applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6770/.
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The present thesis is focused on the study of innovative Si-based materials for third generation photovoltaics. In particular, silicon oxi-nitride (SiOxNy) thin films and multilayer of Silicon Rich Carbide (SRC)/Si have been characterized in view of their application in photovoltaics. SiOxNy is a promising material for applications in thin-film solar cells as well as for wafer based silicon solar cells, like silicon heterojunction solar cells. However, many issues relevant to the material properties have not been studied yet, such as the role of the deposition condition and precursor gas concentrations on the optical and electronic properties of the films, the composition and structure of the nanocrystals. The results presented in the thesis aim to clarify the effects of annealing and oxygen incorporation within nc-SiOxNy films on its properties in view of the photovoltaic applications. Silicon nano-crystals (Si NCs) embedded in a dielectric matrix were proposed as absorbers in all-Si multi-junction solar cells due to the quantum confinement capability of Si NCs, that allows a better match to the solar spectrum thanks to the size induced tunability of the band gap. Despite the efficient solar radiation absorption capability of this structure, its charge collection and transport properties has still to be fully demonstrated. The results presented in the thesis aim to the understanding of the transport mechanisms at macroscopic and microscopic scale. Experimental results on SiOxNy thin films and SRC/Si multilayers have been obtained at macroscopical and microscopical level using different characterizations techniques, such as Atomic Force Microscopy, Reflection and Transmission measurements, High Resolution Transmission Electron Microscopy, Energy-Dispersive X-ray spectroscopy and Fourier Transform Infrared Spectroscopy. The deep knowledge and improved understanding of the basic physical properties of these quite complex, multi-phase and multi-component systems, made by nanocrystals and amorphous phases, will contribute to improve the efficiency of Si based solar cells.
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Levichkova, Marieta. "Influence of the Matrix Environment on the Optical Properties of Incorporated Dye Molecules." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1205766500301-30732.
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The present thesis is concerned with solid solutions of organic dyes. The organic molecules are incorporated in both optically inert or active and in rigid or flexible matrices, respectively. Exclusively thin films prepared by physical vapor deposition are studied. The optical response of the systems, in dependence on their structure and on the matrix nature, is investigated by means of absorption and luminescence spectroscopy. In the first part, perylene and 2,2-difluoro-1,3,2-dioxaborine derivatives, and Alq3 (tris(8-hydroxyquinoline) aluminium) embedded in the optically inactive SiO2 and polyimide hosts are studied. For the system dye molecules/SiO2 matrix, two sample preparation approaches, co-deposition and layer-by-layer, are compared. It is demonstrated that the luminescence properties of the mixed layers are affected by dye distribution and thin film composition. The photoluminescence quantum efficiency is strongly influenced by dye aggregation and Föster transfer. Therefore, effective separation and isolation of dye molecules in the matrix results in increased PL efficiency. Furthermore, it is established that layer-by-layer growth mode assures more homogeneous dye distribution. The spectroscopic studies also show that, since dye and matrix condense successively in time, luminescence losses due to thermal degradation of molecules are reduced. Hence, the film structure can be optimized with regard to high absorption and luminescence quantum efficiency. The experimental findings suggest that the luminescent properties of the embedded dyes are influenced by the nature of the host environment as well. In the rigid SiO2 matrix, it is possible to observe isolated facial Alq3 molecules with distinctive blue luminescence. In contrast, in the "soft" organic polyimide matrix Alq3 exhibits ordinary green luminescence. Thus, the structural properties of the host, rigidity and density, are found to be crucial for preservation of the facial Alq3 molecules. It is further demonstrated that the immobilization of molecules in the rigid SiO2 matrix in combination with layer-by-layer growth results in improved photostability. In polyimide matrix, the behavior of incorporated molecules is governed by the morphological changes of the host. These changes are defined by the curing procedure, needed for imidization, and give rise to a certain film structure. In the second part, special attention is paid on the luminescence response of dispersed DCM (4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyril)-4H-pyran) and rubrene (5,6,11,12-tetraphenyl-naphthacene) molecules in the optically active Alq3 matrix. The observed enhancement of luminescence intensity and alteration of emitted color are favorable for application of the doped Alq3 films as converter layers in combination with commercial blue light emitting diodes in luminescence conversion devices. It is demonstrated that by optimization of the conversion layer parameters white light generation can be achieved. The devices are characterized by high conversion efficiency and Lambertian distribution of the emitted light. However, they lack sufficient stability with regard to practical applications.
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Meier, Matthias. "Die Rolle der Global Reporting Initiative bei der Selektion nachhaltiger Kapitalanlagen am Beispiel der Bank Sarasin Sustainability Matrix." St. Gallen, 2008. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/01652403003/$FILE/01652403003.pdf.
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Perrier, Amélie. "Influence du vieillissement hydrique suer le comportement mécanique de l'interface fil/matrice dans les composites chanvre/époxy." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2016. http://www.theses.fr/2016ESMA0019/document.
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Cette étude porte sur l’analyse de l’influence de l’eau sur des composites chanvre/époxy. Deux résines ont été utilisées, l’une 100 % pétrochimique (Epolam) et l’autre partiellement bio-sourcée (Greenpoxy). L’absorption d’eau d’éprouvettes de composites tissés a d’abord été suivie par des mesures gravimétriques. Les résultats ont mis en évidence une cinétique d’absorption de type Langmuir dépendant de plusieurs paramètres (types de résine, de fibres et de tissu, fraction volumique de fibres et épaisseur). Des essais de DMA et DSC sur les résines ont montré un effet plastifiant de l’eau ainsi qu’une modification irréversible de leurs propriétés après le vieillissement hydrique. Des observations microscopiques réalisées sur le composite et à l’échelle du fil ont permis de détecter que des fissures entre les fibres de chanvre et la matrice époxy apparaissent et se développent dès le début de la désorption. De surcroît, des observations en photoélasticimétrie ont montré une réorganisation des contraintes internes irréversible due à ces endommagements. Des essais de traction quasi-statiques ont ensuite été réalisés sur des composites tissés et sur les résines seules. Le vieillissement hydrique modifie les grandeurs mécaniques ainsi que l’évolution des endommagements, suivie par émission acoustique et tomographie X.Pour mieux appréhender le comportement de l’interface fil/matrice, différents tests ont été développés sur des éprouvettes monofilamentaires spécifiques dans lesquelles le fil est orienté à 45° ou 90° par rapport à l’axe de sollicitation. Tout d’abord, des tests de nanoindentation ont été effectués de manière à mesurer in situ les propriétés de chaque constituant des composites avant et après vieillissement hydrique. Un second type de test basé sur le principe du choc laser a été utilisé pour déterminer la qualité de l’adhérence entre le fil et la résine. Enfin, des essais de traction sur micromachine sous microscope optique ont été mis au point dans le but de mesurer les champs de déformations par corrélation d’images. Les résultats ont démontré que les déformations locales sont plus importantes après un vieillissement hydrique et que ce phénomène est plus accentué dans le chanvre/Greenpoxy que dans le chanvre/Epolam. Le développement d’un modèle numérique simplifié a permis d’approcher la loi de comportement locale des différents constituants du composite et d’étudier l’évolution des modules après vieillissementThis study deals with the analysis of the influence of water on hemp/epoxy composites. Two resins have been used, one being 100 % petrochemical (Epolam) and the other one partially bio-based (Greenpoxy). The water absorption of the woven composites have been measured with gravimetric analyses. The results showed a Langmuir-type absorption, and depends on several parameters (type of resin, fibres and fabric, fibre ratio and thickness). DMA and DSC tests realised on resins showed the plasticizing effect of water and an irreversible modification of their properties after the water ageing. Microscopic observations of the composite at the yarn scale helped to detect that cracks between hemp fibres and epoxy matrix appear and develop right from the start of the desorption. Moreover, observations by photoelasticimetry showed an irreversible reorganisation of internal stresses due to this damage. Next, quasi-static tensile tests have been performed on woven composites and resins. The water ageing has modified the mechanical properties of the materials as well as the evolution of damage, which has been studied by acoustic emission and X-ray tomography.For a better understanding of the yarn/matrix interface behaviour, different tests have been developed with specific single yarn composites, in which the yarn is oriented at 45° or 90° in regard to the main axis of the specimen. First, nanoindentation tests have been performed, to measure the properties in situ of each component of the composites before and after water ageing. A second type of tests, based on the laser shock wave method, has been used to determine the quality of adhesion between the yarn and the resin. Finally, tensile tests on a micromachine under an optical microscope have been developed with the aim of measuring strain fields by digital image correlation. The results demonstrated that local strains are higher after a water ageing and that this phenomenon is more pronounced in the hemp/Greenpoxy than in the hemp/Epolam. The development of a finite element model led to estimate the local constitutive law of the different components of the composites and to study the evolution of the modulus after the ageing
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SPAGNOLI, SYLVIE. "Polydiacetylenes cristallins : de la chaine isolee 1d en matrice monomere au film mince de polymere." Paris 7, 1995. http://www.theses.fr/1995PA077086.
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Cette these s'inscrit dans le cadre general de la comprehension de l'influence mutuelle de la structure electronique d'une chaine de polymere conjugue (electrons p delocalises) et de la conformation geometrique de celle-ci. Les polymeres conjugues sont en general des solides desordonnes. La theorie decrit presque toujours les proprietes de la chaine isolee en la considerant comme un systeme periodique regulier a une dimension. Il est donc interessant de disposer d'un systeme se rapprochant du systeme theorique. Les polydiacetylenes (pda) cristallins permettent de realiser experimentalement un systeme ordonne de reference. En choisissant convenablement les pda etudies, deux problemes d'interet deviennent experimentalement accessibles: la structure electronique d'une chaine conjuguee unidimensionnelle isolee, objet periodique dans un potentiel periodique impose par son environnement, celui de la matrice cristalline du monomere correspondant. La correspondance entre structure electronique et degre d'ordre conformationnel de la chaine. En effet les pda choisis sont solubles et l'on peut etudier, outre l'etat ordonne de reference decrit ci-dessus, tous les degres d'ordre, du polymere massif cristallin considere comme une collection de telles chaines mais en interaction entre elles, a l'etat le plus desordonne constitue par la chaine isolee en solution diluee. Pour cela, nous avons etudie: des monocristaux de monomere ne contenant que quelques chaines de polymere (taux de polymere x en masse: x 10#-#4). Dans de tels cristaux l'interaction interchaine se trouve minimisee. On peut ainsi esperer connaitre les proprietes electroniques de l'etat ordonne de reference. Des echantillons totalement polymerises mais dans une geometrie specifique, celle de films minces monocristallins. On peut atteindre sur ces films deux structures electroniques differentes, dont l'une est proche de celle observee dans les films amorphes et les gels
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Homoro, Omayma. "Influence de la pré-imprégnation sur le comportement mécanique des composites verre-matrice ettringitique : étude expérimentale et numérique." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1239/document.
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Ces dernières années, les matériaux composites à matrices minérales ont suscité un grand intérêt dans le domaine du génie civil, en raison de leurs multiples avantages tels que la grande résistance en traction, le comportement pseudo-ductile, la facilité de mise en oeuvre, la nontoxicité et la compatibilité aux substrats. Toutefois, l’efficacité de ces composites est souvent limitée du fait de la faible adhérence du renfort avec la matrice. Cela est du à la faible pénétration des particules de la matrice entre les filaments internes du fil, ce qui entraine une rupture prématurée du matériau. Ce travail a pour but d’améliorer l’adhérence fil-matrice par pré-imprégnation du renfort, afin d’optimiser le comportement mécanique des composites. Deux méthodes de pré-imprégnation ont été utilisées : pré-imprégnation classique par voie humide et pré-imprégnation par voie sèche. Cette dernière se base sur l’application d’un champ électrostatique alternatif permettant la pénétration de la poudre au sein du renfort. La première méthode a déjà été utilisée dans la littérature et a permis d’améliorer les propriétés mécaniques du composite. Cependant, son utilisation reste limitée aux éléments préfabriqués simples contrairement à la deuxième méthode qui peut être appliquée pour réaliser des éléments de construction de grande taille, ou bien pour le renforcement et la réparation des structures in situ. La présente étude s’appuie sur une analyse multi-échelles permettant d’aborder le problème d’adhérence à l’échelle d’interface (fil-matrice) et à l’échelle du composite (fil-matrice et textile-matrice). Tout d’abord, des essais d’arrachement ont été conduits sur des fils de verre enrobés dans une matrice ettringitique. Huit configurations ont été étudiées afin d’évaluer l’effet du processus de pré-imprégnation et le type des matériaux de pré-imprégnation à sec. Il en sort que le comportement d’arrachement est amélioré par pré-imprégnation du fil par voie humide et sèche mais, précisons que par voie sèche, l’amélioration est significative seulement dans le cas d’utilisation de poudre de particules très fines. Une modélisation numérique de l’essai d’arrachement a été également réalisée afin d’identifier les propriétés d’interface fil-matrice. En se basant sur ces résultats, une étude expérimentale et numérique du comportement en traction des composites fil-matrice a été ensuite réalisée. Cinq configurations ont été retenues, après avoir écarté les prétraitements de fil ayant eu un effet néfaste sur l’adhérence fil-matrice. Il s’est avéré que les deux procédés contribuent à une augmentation significative des propriétés mécaniques du composite. De plus, un modèle numérique 3D a été développé pour simuler l’essai de traction d’un composite sec et pré-imprégné. Il a permis d’une part de prédire le comportement global du matériau et d’autre part d’apporter une meilleure compréhension de ce comportement grâce à l’analyse des états de déformation et de contrainte au niveau du fil, de la matrice et de l’interface. Enfin, une comparaison de l’effet des deux procédés de pré-imprégnation a été établie à l’échelle du composite textile-matrice au moyen d’essais de traction et d’analyse de corrélation d’image. Cinq différents types de tissu de verre unidirectionnel ont été utilisés. La pré-imprégnation par voie sèche a démontré la plus forte amélioration des performances du composite quel que soit le grammage du tissu, contrairement à la pré-imprégnation par voie humide qui trouve sa limite quand le textile devient denseIn recent years, mineral matrix composites have gained great interest in the field of civil engineering, thanks to their multiple advantages such as high tensile strength, pseudo-ductile behavior, ease of implementation, non-toxicity and substrate compatibility. However, the efficiency of these composites is often limited because of the low adhesion of the reinforcement to the matrix. This is due to the low penetrability of matrix particles into the space between the inner filaments of the yarn, which leads to premature failure of the material. The purpose of this work is to improve the yarn-matrix adhesion by pre-impregnating the reinforcement in order to optimize the mechanical behavior of composites. Two pre-impregnation methods were used : conventional pre-impregnation in a wet manner and pre-impregnation in a dry manner. This last is based on an alternating electrostatic field used to impregnate yarns with powder. The first method has already been used in the literature and has improved the mechanical properties of the composite. However, it is suited only for the manufacturing of simple prefabricated elements, unlike the second method, which can be applied for the construction of large elements, or for strengthening or repairing structures in site. This study is based on a multi-scale analysis to investigate the bond problem at the interface scale (yarn-matrix) and at the composite scale (yarn-matrix and textile-matrix). First, pull-out tests were conducted on glass yarns embedded in an ettringitic matrix. Eight configurations were studied to evaluate the effect of the pre-impregnation process and the type of dry pre-impregnation powders. It results that the pull-out behavior is improved by pre-impregnating the yarn in wet and dry manner but, it should be noted that in dry process, the improvement is significant only when using very fine particle powders. A numerical modeling of the pull-out test was also carried out in order to identify the yarn-matrix interface properties. Based on these results, an experimental and numerical study of the tensile behavior of yarn-matrix composites was then carried out. Five configurations were selected, after excluding the yarn pre-treatments that had a negative effect on the yarn-matrix bond. It was found that both processes contribute to a significant increase in the mechanical properties of the composite. In addition, a 3D numerical model has been developed to simulate the tensile test of a dry and pre-impregnated composite. It allowed on the one hand to predict the global behavior of the material and on the other hand to provide a better understanding of this behavior by analyzing the deformation and stress states at the level of the yarn, the matrix and the interface. Finally, a comparison of the effect of the two pre-impregnation processes was established at the textile-matrix composite scale by means of tensile tests and image correlation analysis. Five different types of unidirectional glass fabric were used. The dry pre-impregnation has shown the best improvement in composite performance regardless of fabric density, unlike the wet pre-impregnation, which has its limits when the textile becomes dense
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Scidà, Alessandra <1985>. "Ion implantation of organic thin films and electronic devices." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5205/.
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Organic semiconductors have great promise in the field of electronics due to their low cost in term of fabrication on large areas and their versatility to new devices, for these reasons they are becoming a great chance in the actual technologic scenery. Some of the most important open issues related to these materials are the effects of surfaces and interfaces between semiconductor and metals, the changes caused by different deposition methods and temperature, the difficulty related to the charge transport modeling and finally a fast aging with time, bias, air and light, that can change the properties very easily. In order to find out some important features of organic semiconductors I fabricated Organic Field Effect Transistors (OFETs), using them as characterization tools.
The focus of my research is to investigate the effects of ion implantation on organic semiconductors and on OFETs. Ion implantation is a technique widely used on inorganic semiconductors to modify their electrical properties through the controlled introduction of foreign atomic species in the semiconductor matrix. I pointed my attention on three major novel and interesting effects, that I observed for the first time following ion implantation of OFETs:
1) modification of the electrical conductivity;
2) introduction of stable charged species, electrically active with organic thin films;
3) stabilization of transport parameters (mobility and threshold voltage).
I examined 3 different semiconductors: Pentacene, a small molecule constituted by 5 aromatic rings, Pentacene-TIPS, a more complex by-product of the first one, and finally an organic material called Pedot PSS, that belongs to the branch of the conductive polymers. My research started with the analysis of ion implantation of Pentacene films and Pentacene OFETs. Then, I studied totally inkjet printed OFETs made of Pentacene-TIPS or PEDOT-PSS, and the research will continue with the ion implantation on these promising organic devices.
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Albuquerque, Jose Eduardo de. "Estudo por espectroscopia fotoacústica de processos fotoquímicos em uma matriz polimérica." Universidade de São Paulo, 1992. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-01092014-150503/.
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A transferência de elétrons tem sido objeto de um estudo intenso nos últimos anos, por causa da importância deste tipo de reação em processos naturais como a fotossíntese. Com isto, um progresso considerável foi conseguido na proposição de modelos para o centro de reação fotossintético, em particular utilizando o sistema-modelo porfirina-quinona. Nosso intuito e estudar o processo de transferência de elétrons da porfirina para a quinona, aleatoriamente distribuídas em uma matriz polimérica, utilizando a técnica de espectroscopia fotoacústica. A utilização de um filme de polímero como meio tem duas vantagens. A primeira e aproximar nosso sistema-modelo do processo fotossintético natural, no qual os doadores e os aceitadores de elétrons estão envoltos nas proteínas do centro de reação e, portanto, em um meio polimérico. A segunda e possibilitar a utilização desses filmes como possíveis componentes eletrônicos moleculares. Identificamos os estados eletrônicos da porfirina e da quinona e tentamos determinar o estado de cargas separadas, P+ e Q-. A partir dos espectros obtidos, determinamos a eficiência quântica de fluorescência da porfirina utilizada nos filmes. Estudamos, também, a degradação da porfirina nos filmes preparados. Por fim, verificamos o efeito da concentração crescente da quinona nos filmes preparados com a porfirinaThe electron transfer phenomenon has been the subject of intense study for the last years, due to the importance of this kind of reaction in natural processes as photosynthesis. A great improvement has been achieved in the proposition of models for the photosynthetic reaction center, in particular using the porphyrin-quinone model system. Our intention is to study the electron transfer process of the porphyrin to the quinone randomly distributed in a polymeric matrix, using the photo acoustic spectroscopy. The utilization of a polymeric film as an environment has two advantages. The first is to approximate our model system to the natural photosynthetic process, in which the electron donors and acceptors are surrounded by, the proteins of the reaction center, and thus in a polymeric environment. The second is to allow the utilization of these films as possible molecular electronic components. We identified the electronic states of the porphyrin and the quinone, and we attempted to determine the charge separated electronic state. We determined the fluorescence quantum efficiency of the porphyrin films, by their photo acoustic and absorption spectra. Also, we studied the degradation of the porphyrin in the prepared films. Finally, we checked the effect of the increasing concentration of the quinone in the films prepared with the porphyrin
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Carvalho, Flávio Luiz Silva de. "Efeito da matriz no comportamento fotocrômico de ormosils de fosfotungstato." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-25082009-081226/.
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Esta dissertação versa sobre o estudo de filmes híbridos orgânicos-inorgânicos do tipo ormosil com heteropoliânions do tipo Keggin. O heteropoliânion usado nesse trabalho foi: H3PW12O40 enquanto o ormosil foi obtido a partir do processo sol-gel usando tetraetilortossilicato (TEOS) como agente formador da rede 3D de silicatos e organossilanos contendo grupos oxirana e grupos básicos de Lewis nitrogenados. Realizaram-se testes do uso de Poli (dimetilsiloxano), bis (3-aminopropil) terminados (PDMSa) como agentes modificadores nos filmes. Foram obtidos filmes autossuportados e suportados em lâminas de vidro aluminossilicato. O PDMSa e o silano contendo o grupo oxirana levaram a uma queda na rugosidade média quadrática dos filmes como demonstrado nas micrografias obtidas por Microscopia Eletrônica de Varredura (MEV). Medidas de ângulos de contato estático da água sobre os filmes e de Espectroscopia de Fotoelétrons Excitados por Raios-X mostraram que há segregação do PDMSa ou do silano contendo o grupo oxirana na superfície dos filmes, entretanto os filmes com maior ângulo de contato são aqueles contendo PDMSa. Medidas de Espectroscopia de Absorção na Região do Infravermelho (IV) e Espectroscopia de Ressonância Magnética Nuclear com Rotação em Ângulo Mágico no Estado Sólido (RMN) mostraram que ormosis contendo silanos com grupo amino levam a parcial decomposição dos heteropoliânions, enquanto ormosis contendo silanos com o o grupo nitrila resultam em menor taxa de decomposição. Nos ormosis contendo igual proporção em número de moles destes dois silanos observou-se que estes dois grupos devem estar muito próximos e interagindo entre si via ligação de hidrogênio o que resultou numa queda ainda maior da taxa de decomposição. Os ormosis com silanos dotados de grupos oxirana e nitrila apresentaram maior sensibilidade a radiação UV, ou seja, a maior variação de absorbância e menor tempo de retorno à cor original. Estes filmes mostraram reprodutibilidade e não perderam sua atividade fotocrômica após serem submetidos a 10 ciclos sucessivos de irradiação com UV. Os filmes mostraram resposta linear da função de refletância com a dose de radiação UVB na faixa de 0,80 até 69 MED. Desta forma nós demonstramos a possibilidade de se obter filmes fotocrômicos reprodutíveis e estáveis e como controlar sua sensibilidade usando o processo sol-gel.This thesis aim to study the organic-inorganic hybrid films of the organosilanes with heteropolyanions of the Keggin type. The heteropolyanion used in this study was H3PW12O40 while the ormosil was obtained by the sol-gel process using tetraethylortossilicate (TEOS) to build the 3D silicate network and organosilanes bearing the oxirane and Basic Lewis nitrogenated groups. Poly (dimethylsiloxane), terminated with (3-aminopropyl) groups, (PDMSa) was essayed as modifiers agents in the film. The films were supported on aluminosilicate glass substrates and self-suported ones. PDMSa or oxirane bearing silanes addition results on smoother filmes reporting lower mean square root roughness based on electron micrographies obtained by Scanning Electron Microscopy (SEM). Water static contact angle measurements and X-ray Photoemission Spectroscopy (XPS) pointed out the surface segregation of the PDMSa and oxirane bearing silane, however higher contact angles were observed for the PDMSa based films. InfraRed Absorption Spectroscopy (IR) and Magic Angle Spinning Nuclear Magnetic Resonance spectroscopy (MAS NMR) results demonstrate that in ormosis with silanes bearing amino groups there was phosphotungstic acid decomposition while in ormosis with nitrile groups such decomposition is much less pronounced. For mixed ormosis with even proportion of amino and nitrile bearing silanes those functional groups are close enough to interact through hydrogen bonding resulting on even lower decomposition of the Phosphotungstate oxocluster. Those films with nitrile functional groups showed higher photochromic activity and faster bleaching time. The films showed high reproducibility and did not loose their photochromic activity after ten cycles of UV irradiation. The films bearing nitrile functionality showed linear response of the reflectance function as a function of the irradiation dose between 0,80 and 69 MED. Therefore, it was demonstrated the possibility to use sol-gel process to obtain photochromic ormosis.
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Levichkova, Marieta. "Influence of the Matrix Environment on the Optical Properties of Incorporated Dye Molecules." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A24056.
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The present thesis is concerned with solid solutions of organic dyes. The organic molecules are incorporated in both optically inert or active and in rigid or flexible matrices, respectively. Exclusively thin films prepared by physical vapor deposition are studied. The optical response of the systems, in dependence on their structure and on the matrix nature, is investigated by means of absorption and luminescence spectroscopy. In the first part, perylene and 2,2-difluoro-1,3,2-dioxaborine derivatives, and Alq3 (tris(8-hydroxyquinoline) aluminium) embedded in the optically inactive SiO2 and polyimide hosts are studied. For the system dye molecules/SiO2 matrix, two sample preparation approaches, co-deposition and layer-by-layer, are compared. It is demonstrated that the luminescence properties of the mixed layers are affected by dye distribution and thin film composition. The photoluminescence quantum efficiency is strongly influenced by dye aggregation and Föster transfer. Therefore, effective separation and isolation of dye molecules in the matrix results in increased PL efficiency. Furthermore, it is established that layer-by-layer growth mode assures more homogeneous dye distribution. The spectroscopic studies also show that, since dye and matrix condense successively in time, luminescence losses due to thermal degradation of molecules are reduced. Hence, the film structure can be optimized with regard to high absorption and luminescence quantum efficiency. The experimental findings suggest that the luminescent properties of the embedded dyes are influenced by the nature of the host environment as well. In the rigid SiO2 matrix, it is possible to observe isolated facial Alq3 molecules with distinctive blue luminescence. In contrast, in the "soft" organic polyimide matrix Alq3 exhibits ordinary green luminescence. Thus, the structural properties of the host, rigidity and density, are found to be crucial for preservation of the facial Alq3 molecules. It is further demonstrated that the immobilization of molecules in the rigid SiO2 matrix in combination with layer-by-layer growth results in improved photostability. In polyimide matrix, the behavior of incorporated molecules is governed by the morphological changes of the host. These changes are defined by the curing procedure, needed for imidization, and give rise to a certain film structure. In the second part, special attention is paid on the luminescence response of dispersed DCM (4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyril)-4H-pyran) and rubrene (5,6,11,12-tetraphenyl-naphthacene) molecules in the optically active Alq3 matrix. The observed enhancement of luminescence intensity and alteration of emitted color are favorable for application of the doped Alq3 films as converter layers in combination with commercial blue light emitting diodes in luminescence conversion devices. It is demonstrated that by optimization of the conversion layer parameters white light generation can be achieved. The devices are characterized by high conversion efficiency and Lambertian distribution of the emitted light. However, they lack sufficient stability with regard to practical applications.
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Sampaio, Cardoso Leonardo. "Orthogonal Precoder for Dynamic Spectrum Access in Wireless Networks." Thesis, Supélec, 2011. http://www.theses.fr/2011SUPL0018/document.
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Le déferlement mondial des services de télécommunications, impose, aux réseaux qui les supportent, d’augmenter de plus en plus leurs capacités afin de subvenir aux besoins de ses utilisateurs dont le nombre ne cesse de croître. Le spectre radio, ressource de base pour les communications sans fils, ne suit malheureusement pas cette croissance. Même si des marges réutilisables sont disponibles, leur accès est limité par des politiques strictes de gestion du spectre radio-fréquentiel. Pour remédier à cette situation, les organismes régulateurs des télécommunications se dirigent vers un paradigme de gestion plus flexible, en autorisant de nouvelles méthodes basées sur l’accès dynamique au spectre (DSA - dynamic spectrum access) et les radio cognitives (CR - cognitive radio). Dans ce travail doctoral, est proposée une nouvelle technique pour traiter la problématique de la disponibilité du spectre radio-fréquentiel. Appelée multiplexage fréquentiel par sous-espace de Vandermonde (VFDM -Vandermonde-subspace frequency division multiplexing), elle permet à deux technologies d’accès radio (RATs - radio access technologies) de fonctionner côte-a-côte dans un environnement de petites cellules CR. Ceci se fait en partageant la bande radio tout en protégeant des interférences les systèmes pour lesquels le spectre radio avait été originellement réservé. VFDM transmet les données pré-codées dans le noyau du canal interférant entre l’émetteur opportuniste et le récepteur originel en utilisant la sélectivité en fréquence des canaux et duplexage temporel (TDD - time division duplexing). Le travail de cette thèse propose une approche exhaustive du développement de la technologie VFDM, en allant des bases théoriques jusqu’à la démonstration de faisabilité. Ainsi, les bases théoriques proposées ont été en premier lieu analysées. Puis, en partant de ces bases théoriques, VFDM a été graduellement développé vers une chaîne émetteur-récepteur complète. Des résultats significatifs sont apparus à mi-chemin dans la phase de développement, comme par exemple, l’établissement de stratégies de précodage optimales ou la mise en évidence d‘aspects critiques lors de l’implémentation. Sous certaines conditions, VFDM permet aux réseaux secondaires opportunistes d’être utilisés en même temps que le réseau originel, aux seules contraintes de la connaissance des canaux et de l’accroissement de la complexité du système. Au travers des résultats obtenus en simulation, il a été démontré que des taux de transfert de données significatifs peuvent être atteints, et ce, malgré que les capacités de VFDM soient toujours limitées par la taille du sous-espace de Vandermonde du canal interfèrent primaire-secondaire. Finalement, la chaîne émetteur-récepteur développée démontre la faisabilité de cette méthodeThe global deployment of PCS is pushing for more and more network capacity to accommodate an exponentially growing user base. Radio spectrum, the basic resource in radio communications, unfortunately does not follow this growth. Even though the current spectrum usage leaves margins for re-use, it is limited by the current fixed spectrum management policies. To remediate this issue, spectrum regulators are switching to a flexible management paradigm, leveraging new DSA schemes based on CR. In this PhD work, a novel CR-DSA technology is introduced to address spectrum scarcity problem. Called VFDM, it allows two RAT to operate side-by-side in a small-cell CR setting, sharing the band while protecting the legacy system from interference. VFDM transmits data pre-coded on the null-space of the interfering cross channel (channel from the opportunistic transmitter to the legacy receiver), assuming frequency selectivity and TDD communications. This PhD work proposes a rather exhaustive approach to the development of VFDM: to go from the theoretical basis up to a proof-of-concept development. Initially the theoretical background, basis of the technique itself was introduced and analyzed. Then, VFDM was gradually developed from a pure mathematical concept up to a full transceiver. During this development, several important mid-way results were developed, such as the multi-user strategy for pre-coding and critical implementation aspects. VFDM, under certain constraints, has been shown to allow a secondary opportunistic network to successfully be installed along with a legacy primary one at merely the cost of channel knowledge and added complexity. By means of numerical examples, it has been shown that significative rates can be attained, even though VFDM's performance is constrained by the size of the Vandermonde-subspace of the interfering channel between the secondary transmitter and primary receiver. Finally, a working VFDM transceiver implementation is shown, providing a proof-of-concept of the technique
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Chauvin, Serge. "L'écran de la conscience : le film, modèle et matrice de la fiction chez Pynchon, Coover, DeLillo." Paris 4, 1996. http://www.theses.fr/1996PA040275.
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Pynchon,Coover et DeLillo appartiennent à la première génération littéraire américaine pour qui le cinéma est allé de soi,au point d'informer et de nourrir leur fiction. Le film représente pour eux à la fois une mythologie cohérente et vivace et un dispositif de perception du monde qui fait la part belle à l'expérience du spectateur. Ils mettent donc en scène des personnages cinéphiles voire comme Coover le programme exhaustif d'une séance de cinéma et les processus techniques du cinéma sont autant d'outils pour métamorphoser leur rapport au réel. Un réel qui notamment chez DeLillo tend à se réduire à une scène autoparodique. Le cinéma induit aussi une façon nouvelle de penser et de vivre le temps,sur le mode à la fois de la répétition et de l'irréversible,ne laissant que le spectacle rétrospectif d'une catastrophe. Cette face sombre du ballet d'images amène à chercher une issue : violence vouée à l'échec ou tentation du décalage chez DeLillo,célébration alanguie chez Coover,définition d'un espace interstitiel chez PynchonPynchon,Coover and DeLillo have been among the first novelists in American literature to take the moviegoing experience for granted. .
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Adhikari, Dipendra. "Optical and Microstructural Properties of Sputtered Thin Films for Photovoltaic Applications." University of Toledo / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1573118517150321.
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Liebenberg, J. G. (Johannes Gideon). "'n Ondersoek na die verbetering van matriksbestuur in GERATEC." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52364.
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Thesis (MBA)--Stellenbosch University, 2001.ENGLISH ABSTRACT: The increasing demands on modern day organisations in terms of profitability are based on enhanced effectiveness and productivity. Geratec is a specialist catering company with the elderly as target market. The operation of Geratec makes a framework for effective matrix organisation and improvement thereof a matter of utmost importance. The questionnaire that is used in this document is specifically designed according to the framework for an effective matrix organisation. The results of the questionnaire are used to compile a matrix profile for Geratec. Possible problem areas can be identified and addressed accordingly. The problem areas that were identified are as follows: • Performance management, • Remuneration and acknowledgement, • Shared goals, and • Empowerment. According to the results of the questionnaire, the latter is least present in the organisation. Empowerment must therefor be seen as a departure for the establishment of a framework for an effective matrix organisation. The recommendations and suggestions in this document strives to establish the roles of the principal shareholders, who are, • Top management, • Project managers, • Functional managers, • Team players. As concluding remark, this document created awareness at Geratec for the framework of the improvement of matrix management. The improvement of matrix management must be handled with utmost care because of inevitable resistance to change. Visible top management support is therefor of vital importance.
AFRIKAANSE OPSOMMING: Die toenemende eise wat aan moderne organisasies gestel word in terme van winsgewindheid word gebaseer op verhoogde effektiwiteit en produktiwiteit. Geratec is 'n spesialis spysenieringsmaatskappy met bejaardes as die teikenmark. Die funksionering van Geratec maak 'n raamwerk vir effektiewe matriks organisasie en die verbetering daarvan, onontbeerlik. Die vraelys wat in hierdie dokument gebruik word, is ontwerp volgens die raamwerk vir 'n effektiewe matriks organisasie. Die resultate van die vraelys word gebruik vir die samestelling van 'n matriks profiel vir Geratec. Identifikasie en regstelling van probleemareas word sodoende moontlik gemaak. Geïdentifiseerde probleemareas by Geratec is as volg: • Prestasiebestuur • Vergoeding en erkenning, • Gemeenskaplike doelwitte, en • Bemagtiging. Laasgenoemde verg volgens die resultate van die vraelys die meeste aandag. Bemagtiging moet dus as die vertrekpunt vir die daarstelling van 'n raamwerk vir 'n effektiewe matriks organisasie gesien word. Die aanbevelings en voorstelle in hierdie dokument strewe na die vestiging van die rolle van die hoof aandeelhouers, naamlik: • Topbestuur • Projekbestuurders • Funksionele bestuurders • Spanlede Ten slotte word daar deur hierdie dokument 'n bewustheid geskep by Geratec vir 'n raamwerk vir die verbetering van matriksbestuur. Die verbetering van matriksbestuur moet versigtig aangepak word as gevolg van die onvermydelike weerstand teen verandering. Waarneembare ondersteuning van Topbestuur is dus essensieel.
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Darby, Rene. "The development of a decision-making matrix to address the South African power crisis." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/4921.
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Thesis (MBA (Business Management))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: This research report discusses the development of a decision-making matrix during power crises. South Africa comes from a situation of excess supply and is currently in a situation where electricity demand exceeds supply. This report will provide the background of how the current electricity crisis came to be and what the future of the industry will look like. As electricity shortages is a worldwide issue, the study will explore international countries' experience of supply shortages and extract lessons learnt and best practices that can be applied in the South African context. The study reviews available solutions that exist to address the electricity crisis in South Africa and explores alternative energy sources that could be applied in South Africa. To establish an effective decision making tool for electricity shortage response mechanisms, the key decision making criteria are discussed and explained. A decision making matrix brings together all the available solutions and decision-making criteria based on the decision maker's relative importance placed on the considerations and the resultant impact on these considerations. The results of the decision-making matrix directs the decision maker to the least negative impact solution and provides a basis on which to make sound decisions during a time when quick and effective decisions will determine the success and sustainability of the power system.
AFRIKAANSE OPSOMMING: Hierdie navorsingsverslag bespreek die ontwikkeling van 'n besluitnemingsmodel wat aangewend kan word tydens kritiese tekorte in elekrisiteitsvoorsiening op 'n nasionale basis. Die elektrisiteits- ontwikkelingsvermoë in Suid-Afrika het beweeg vanaf 'n oorskot na 'n posisie waar daar nie in die aanvraag voorsien kan word nie. Hierdie navorsingsverslag skets die agtergrond van wat aanleiding gegee het tot die huidige elektrisiteitskrisis en wat die toekoms inhou vir elektrisiteitsvoorsiening in die algemeen. Die gebrek aan elektrisiteitsontwikkelingsvermoë is 'n wêreldwye tendens en die lesse wat ander lande geleer het tesame met hul beste praktyke word oorweeg binne die Suid-Afrikaanse konteks. Beskikbare oplossings wat op die manier geidentifiseer word, word ontleed, tesame met moontlike alternatiewe energiebronne wat in Suid-Afrika aangewend kan word. Die kern besluitnemingskriteria word bespreek en ontleed om sodoende 'n proses daar te stel waarvolgens die besluitnemingsmodel wat die mees effektiewe oplossing in tye van kritiese elektirsiteitstekorte sal voortbring te ontwikkel. Al die beskikbare en werkbare opsies tydens die periode van elektristeitstekorte word saamgevoeg binne die besluitnemingsmodel om die toepaslikheid daarvan op te weeg teenoor die relatiewe gewig wat die besluitnemer toeken aan al die onderliggende faktore. Die besluitnemingsmodel ondersteun die besluitnemer om, tydens 'n krisis in elektrisiteitsvoersiening, 'n vinnige en doeltreffende besluit te neem wat die minste negatiewe impak het op ekonomiese aktiwiteite en die sukses en stabiliteit van die elektrisiteitsvoorsieningsnetwerk waarborg.
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Hoydis, Jakob. "Random matrix theory for advanced communication systems." Phd thesis, Supélec, 2012. http://tel.archives-ouvertes.fr/tel-00765458.
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Advanced mobile communication systems are characterized by a dense deployment of different types of wireless access points. Since these systems are primarily limited by interference, multiple-input multiple-output (MIMO) techniques as well as coordinated transmission and detection schemes are necessary to mitigate this limitation. Thus, mobile communication systems become more complex which requires that also the mathematical tools for their theoretical analysis must evolve. These must be able to take the most important system characteristics into account, such as fading, path loss, and interference. The aim of this thesis is to develop such tools based on large random matrix theory and to demonstrate their usefulness with the help of several practical applications, such as the performance analysis of network MIMO and large-scale MIMO systems, the design of low-complexity polynomial expansion detectors, and the study of random beamforming techniques as well as multi-hop relay and double-scattering channels. The methods developed in this work provide deterministic approximations of the system performance which become arbitrarily tight in the large system regime with an unlimited number of transmitting and receiving devices. This leads in many cases to simple and close approximations of the finite-size system performance and allows one to draw relevant conclusions about the most significant parameters. One can think of these methods as a way to provide a deterministic abstraction of the physical layer which substantially reduces the system complexity. Due to this complexity reduction, it is possible to carry out a system optimization which would be otherwise intractable.
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Chang, Ku-Wei, and 張谷維. "Controlled release of narcotics using matrix and matrix-film coating systems." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/41465770946902294706.
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碩士嘉南藥理科技大學
生物科技系暨研究所
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The major purpose of this study was to compare the release kinetics of tramadol from various controlled release systems. Tramadol, a narcotics often used in treatment of chronic pain, was used as a water soluble model drug. The various systems studied including hydrophobic matrix, hydrophilic matrix and matrix-film coating systems. The drug release from hydrophobic matrix using various manufacture processes, including wet granulation method and fusion-granulation method, was also evaluated. The results indicate that prolonged tramadol release can be observed by incorporation of drug into both hydrophobic and hydrophilic matrix systems. Drug release from those systems followed a Higuchi release model, suggesting a diffusional release mechanism. The release rate of tramadol was further decreased by coating a rate controlling membrane on top of matrix and the results suggest both matrix as well as coating membrane controlled the release rate. Moreover, the fusion-granulation method provided a better sustaining effect compared to the wet granulation method. Those studies indicate that, by changing the manufacture process and adding rate controlling membrane, an in vitro prolonged release of tramadol up to 24 hours can be obtained.
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Hung, Li-jen, and 洪立仁. "Digital Philosophy exhibited in Film: The Matrix Trilogy." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/53091892581330636100.
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碩士南華大學
建築與景觀學系環境藝術碩士班
101
The purpose of this thesis is to analyze the movie trilogy "The Matrix" which includes contents of both Oriental and Western philosophy. As the object and scope for this thesis, The Matrix trilogy contains a total time in nearly seven hours of video and about thirty thousand words in dialogues. The comparative analysis conducted on the film is to demonstrate how philosophical connotations are realized in the digital world. The research conducted for this thesis was supported by the results to show a successful attempt to expand all digital philosophy covered in the movie "The Matrix". By studying the movie dialogue and the story scenes it was clear to see philosophers such as Nietzsche, Deleuze, Bergson, St. Augustine, Lyotard were used as primary reference. Analyzing the arguments set forward by philosophers to explore The Matrix trilogy for the film''s various digital and philosophical metaphors. And it was found that the implied meaning of the scene, text, symbol throughout the movie enticed an audience to create a post-modern cultural phenomenon like “The Matrix”.