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High-throughput screening: speeding up porous materials discoveryWollmann, Philipp, Leistner, Matthias, Stoeck, Ulrich, Grünker, Ronny, Gedrich, Kristina, Klein, Nicole, Throl, Oliver, Grählert, Wulf, Senkovska, Irena, Dreisbach, Frieder, Kaskel, Stefan 31 March 2014 (has links) (PDF)
A new tool (Infrasorb-12) for the screening of porosity is described, identifying high surface area materials in a very short time with high accuracy. Further, an example for the application of the tool in the discovery of new cobalt-based metal–organic frameworks is given. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Multi-criteria analysis in naval ship designAnil, Kivanc A. 03 1900 (has links)
Approved for public release, distribution is unlimited / Numerous optimization problems involve systems with multiple and often contradictory criteria. Such contradictory criteria have been an issue for marine/naval engineering design studies for many years. This problem becomes more important when one considers novel ship types with very limited or no operational record. A number of approaches have been proposed to overcome these multiple criteria design optimization problems. This Thesis follows the Parameter Space Investigation (PSI) technique to address these problems. The PSI method is implemented with a software package called MOVI (Multi-criteria Optimization and Vector Identification). Two marine/naval engineering design optimization models were investigated using the PSI technique along with the MOVI software. The first example was a bulk carrier design model which was previously studied with other optimization methods. This model, which was selected due to its relatively small dimensionality and the availability of existing studies, was utilized in order to demonstrate and validate the features of the proposed approach. A more realistic example was based on the "MIT Functional Ship Design Synthesis Model" with a greater number of parameters, criteria, and functional constraints. A series of optimization studies conducted for this model demonstrated that the proposed approach can be implemented in a naval ship design environment and can lead to a large design parameter space exploration with minimum computational effort. / Lieutenant Junior Grade, Turkish Navy
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Utilizing Solid Phase Cloning, Surface Display And Epitope Information for Antibody Generation and CharacterizationHu, Francis Jingxin January 2017 (has links)
Antibodies have become indispensable tools in diagnostics, research and as therapeutics. There are several strategies to generate monoclonal antibodies (mAbs) in order to avoid the drawbacks of polyclonal antibodies (pAbs) for therapeutic use. Moreover, the growing interest in precision medicine requires a well-characterized target and antibody to predict the responsiveness of a treatment. This thesis describes the use of epitope information and display technologies to generate and characterize antibodies. In Paper I, we evaluated if the epitope information of a well-characterized pAb could be used to generate mAbs with retained binding characteristics. In Paper II, the epitope on the complement protein C5 towards Eculizumab was mapped with surface display, the results of which explained the non-responsiveness of Eculizumab treatment among a patient group due to a mutated C5 gene. With this in mind, we showed efficacy in treatment of the mutated C5 variants using a drug binding to another site on C5, suggesting that our approach can be used to guide treatment in precision medicine. In Paper III, a Gram-positive bacterial display platform was evaluated to complement existing platforms for selection of human scFv libraries. When combined with phage display, a thorough library screening and isolation of nano-molar binders was possible. In Paper IV, a solid phase method for directed mutagenesis was developed to generate functional affinity maturation libraries by simultaneous targeting of all six CDRs. The method was also used to create numerous individual mutants to map the paratope of the parent scFv. The paratope information was used to create directed libraries and deep sequencing of the affinity maturation libraries confirmed the viability of the combination approach. Taken together, precise epitope/paratope information together with display technologies have the potential to generate attractive therapeutic antibodies and direct treatment in precision medicine. / <p>QC 20170418</p>
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Conception et optimisation d'allocation de ressources dans les lignes d'usinage reconfigurables / Design and optimisation of resources allocation in reconfigurable machining linesEssafi, Mohamed 08 December 2010 (has links)
Les travaux de cette thèse concernent la conception et l’optimisation de lignes de transfert reconfigurables. L’objectif principal est de concevoir une ligne d’usinage à moindre coût tout en respectant les contraintes techniques, technologiques et économiques du problème. Le problème d’optimisation correspondant est un problème d’équilibrage de lignes d’usinage sujet à des contraintes spécifiques. Il consiste à affecter les opérations aux stations de travail en minimisant les coûts d’installation. En plus des contraintes habituelles de ce type de problème, à savoir, les contraintes de précédence, d’inclusion et d’exclusion, nous avons dû considérer des contraintes d’accessibilité. De plus, la spécificité principale des lignes reconfigurables par rapport aux lignes de transfert dédiées, vient de la réalisation en série des opérations. Celle-ci rend souvent nécessaire la mise en place de stations équipées de plusieurs centres d’usinage travaillant en parallèle pour obtenir les volumes de production souhaités. Enfin, l’utilisation d’une tête d’usinage mono-broche induit la prise en compte de temps inter-opératoire de déplacements et de changement d’outils qui dépendent de la séquence d’opérations. Dans un premier temps, nous avons proposé une modélisation mathématique du problème à l’aide d’un programme linéaire en nombres mixtes. Nous avons aussi développé des méthodes de calcul de bornes inférieures ainsi qu’une procédure de prétraitement. Cependant, les contraintes additionnelles rendent la résolution du problème d’équilibrage plus difficile que dans le cas des lignes dédiées, et l’approche proposée ne permet généralement pas de résoudre des instances de taille industrielle. Pour répondre à ce besoin, nous avons donc développé plusieurs méthodes de résolution approchées du problème en nous inspirant de métaheuristiques efficaces sur des problèmes d’optimisation combinatoire. / This work concerns the design and the optimization of reconfigurable transfer lines. The principle objective is to design a machining line with less cost while respecting the technological and economic constraints of the problem. The corresponding optimization problem is a transfer lines balancing problem subject to specific constraints. It consists to affect operations to workstations minimizing the installations cost. In addition to the habitual constraints of the transfer balancing problem, i.e. precedence, inclusion and exclusion constraints, we consider accessibility constraints. In addition, the principal specificity of reconfigurable lines compared to the dedicated transfer lines, comes from the sequential execution of operations. This often makes it necessary to set up stations with several machining centers working in parallel to achieve desired production volumes. Finally, the utilization of mono-spindle head machining center induces the inclusion of setup times between operations. This setup time is due to the time of displacement and change of tools which it depends of the operational sequence. We proposed firstly a mathematical formalization of the problem using a mixed integer program. We developed also several methods to calculate lower bounds and a pretreatment procedure. However, the additional constraints make the resolution of the considered balancing problem very difficult and the proposed approach generally does not solve instances of industrial size. To meet this need, we have developed several approximate resolution methods of the problem taking inspiration from effective Metaheuristics on combinatorial optimization problems.
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Synthesis, Characterization, and Evaluation of Ag-based Electrical Contact MaterialsMao, Fang January 2017 (has links)
Ag is a widely used electrical contact material due to its excellent electrical properties. The problems with Ag are that it is soft and has poor tribological properties (high friction and wear in Ag/Ag sliding contacts). For smart grid applications, friction and wear became increasingly important issues to be improved, due to much higher sliding frequency in the harsh operation environment. The aim of this thesis is to explore several different concepts to improve the properties of Ag electrical contacts for smart grid applications. Bulk Ag-X (X=Al, Sn In) alloys were synthesized by melting of metals. An important result was that the presence of a hcp phase in the alloys significantly reduced friction coefficients and wear rates compared to Ag. This was explained by a sliding-induced reorientation of easy-shearing planes in the hexagonal structure. The Ag-In system showed the best combination of properties for potential use in future contact applications. This thesis has also demonstrated the strength of a combinatorial approach as a high-throughput method to rapidly screen Ag-based alloy coatings. It was also used for a rapid identification of optimal deposition parameters for reactive sputtering of a complex AgFeO2 oxide with narrow synthesis window. A new and rapid process was developed to grow low frictional AgI coatings and a novel designed microstructure of nanoporous Ag filled with AgI (n-porous Ag/AgI) using a solution chemical method was also explored. The AgI coatings exhibited low friction coefficient and acceptable contact resistance. However, under very harsh conditions, their lifetime is too short. The initial tribotests showed high friction coefficient of the n-porous Ag/AgI coating, indicating an issue regarding its mechanical integrity. The use of graphene as a solid lubricant in sliding electrical contacts was investigated as well. The results show that graphene is an excellent solid lubricant in Ag-based contacts. Furthermore, the lubricating effect was found to be dependent on chemical composition of the counter surface. As an alternative lubricant, graphene oxide is cheaper and easier to produce. Preliminary tests with graphene oxide showed a similar frictional behavior as graphene suggesting a potential use of this material as lubricant in Ag contacts.
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The Importance of Controlling Composition to Tailor the Properties of Magnetic Thin FilmsFrisk, Andreas January 2016 (has links)
Many physical properties, for example structural or magnetic, of a material are directly dependent on elemental composition. Tailoring of properties through highly accurate composition control is possible in thin films. This work exemplifies such tailoring. A short review is given of the current status for research in the area of permanent magnets, focusing on rare earth element free alternatives, where FeNi in the L10 phase is a possible candidate. Epitaxial FeNi L10 thin films were successfully synthesized by magnetron sputtering deposition of monoatomic layers of Fe and Ni on HF-etched Si(001) substrates with Cu or Cu100-xNix/Cu buffers. The in-plane lattice parameter aCuNi of the Cu100-xNix buffer layer was tuned by the Ni content. Through matching of aFeNi to aCuNi, the strain state (c/a)FeNi was controlled, where c is the out-of-plane lattice parameter. The 001 reflection indicative of chemical order, as measured by resonant x-ray diffraction, was in most cases split in two peaks due to a composition modulation of Fe and Ni. This chemical disorder contributed to that the uniaxial magnetocrystalline anisotropy energy, KU≈0.35 MJ/m3, was smaller than predicted. In later experiments the composition modulation could partly be compensated for. Remaining discrepancies with respect to predicted KU values were attributed to additional disorder induced by surface roughness of the buffer layer. The interface sharpness between Fe and Ni was explored by producing epitaxial symmetric multilayers with individual layer thicknesses n = 4-48 monolayers (ML). For n ≤ 8 ML the films had pure fcc structure, with antiferromagnetic Fe layers. For n ≥ 8 ML the Fe layers relaxed to bcc structure. A combinatorial sputter chamber, which has the capability to deposit samples with composition and thickness gradients, was assembled. A model for simulation of composition and thickness across large substrates, for the conditions in this chamber, is presented. The model is verified by comparison to experimental data. Some challenges inherent in combinatorial sputtering are discussed, and two experimental studies employing the technique are presented as examples. These investigated magnetic and structural properties of Tb-Co films, with 7-95 at.% Tb, and of amorphous and crystalline ternary gradient Co-Fe-Zr films, respectively.
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Partager le savoir du lexicographe: extraction et modélisation ontologique des savoirs lexicographiquesComeau, Sophie 12 1900 (has links)
Cette recherche porte sur la lexicologie, la lexicographie et l’enseignement/apprentissage du lexique. Elle s’inscrit dans le cadre du projet Modélisation ontologique des savoirs lexicographiques en vue de leur application en linguistique appliquée, surnommé Lexitation, qui est, à notre connaissance, la première tentative d’extraction des savoirs lexicographiques — i.e. connaissances déclaratives et procédurales utilisées par des lexicographes — utilisant une méthode expérimentale. Le projet repose sur le constat que les savoirs lexicographiques ont un rôle crucial à jouer en lexicologie, mais aussi en enseignement/apprentissage du lexique. Dans ce mémoire, nous décrirons les méthodes et les
résultats de nos premières expérimentations, effectuées à l’aide du Think Aloud Protocol (Ericsson et Simon, 1993). Nous expliquerons l’organisation générale des expérimentations et comment les savoirs lexicographiques extraits sont modélisés pour former une
ontologie. Finalement, nous discuterons des applications possibles de nos travaux en enseignement du lexique, plus particulièrement pour la formation des maîtres. / This research is about lexicology, lexicography and vocabulary teaching/learning. It is part of a project called Ontologization of lexicographic abilites for use in the fields of applied linguistics, nicknamed Lexitation, which is, to our knowledge, the first attempt at extracting lexicographic abilities using experimental techniques. The project relies on the assumption that lexicographic abilities play a role in teaching and acquisition
of lexical knowledge, and not only in lexicography per se. We will describe the methods and results of our initial set of experiments, that are based on the use of so-called
Think Aloud Protocol (Ericsson et Simon, 1993). We will explain how experiments have been set up and how we are currently proceeding with the extraction and modeling of various types of knowledge and strategies used by lexicographers while performing lexicographic tasks. Finally, we will present possible applications of our work in the field of language teaching, more specifically, teachers’ training.
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Évaluation de deux méthodes d’identification des liens lexicaux : méthode manuelle et méthode statistiquePoudrier, Caroline 05 1900 (has links)
Ce mémoire présente une évaluation des différentes méthodes utilisées en lexicographie afin d’identifier les liens lexicaux dans les dictionnaires où sont répertoriées des collocations.
Nous avons ici comparé le contenu de fiches du DiCo, un dictionnaire de dérivés sémantiques et de collocations créé selon les principes de la lexicologie explicative et combinatoire, avec les listes de cooccurrents générées automatiquement à partir du corpus Le Monde 2002. Notre objectif est ici de proposer des améliorations méthodologiques à la création de fiches de dictionnaire du type du DiCo, c’est-à-dire, des dictionnaires d’approche qualitative, où la collocation est définie comme une association récurrente et arbitraire entre deux items lexicaux et où les principaux outils méthodologiques utilisés sont la compétence linguistique de ses lexicographes et la consultation manuelle de corpus de textes. La consultation de listes de cooccurrents est une pratique associée habituellement à une approche lexicographique quantitative, qui définit la collocation comme une association entre deux items lexicaux qui est plus fréquente, dans un corpus, que ce qui pourrait être attendu si ces deux items lexicaux y étaient distribués de façon aléatoire. Nous voulons mesurer ici dans quelle mesure les outils utilisés traditionnellement dans une approche quantitative peuvent être utiles à la création de fiches lexicographiques d’approche qualitative, et de quelle façon leur utilisation peut être intégrée à la méthodologie actuelle de création de ces fiches. / This paper presents an evaluation of the various methods used in lexicography in order to identify the lexical bonds in dictionaries where collocations are indexed. We compared the contents of entries of the DiCo, a dictionary of semantic derivatives and collocations created according to the principles of explanatory and combinative lexicology, with the lists of cooccurrents generated automatically from the Le Monde 2002 corpus. Our objective here is to propose improvement in the methodology of creation of dictionary entry of DiCo-like dictionaries, i.e., dictionaries of a qualitative approach, where collocation is defined as the recurring and arbitrary associations between two lexical items and where the principal methodological tools used are the linguistic ability of its lexicographers and the manual consultation of corpus of text. The consultation of lists of cooccurrents is a practice associated traditionally with a quantitative lexicographical approach, which defines collocation as an association between two lexical items, which is more frequent, in a corpus, than what could be expected if these two lexical items were randomly distributed in corpus. We want to evaluate in what respect the tools used traditionally in a quantitative approach can be used for the creation of lexicographical entries of a qualitative approach, and how their use can be integrated into the current methology of creation of these entries.
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Représentations du sens lexical en lexicologie explicative et combinatoire : étude de trois formalisations spécifiquesSamson-Fauteux, Mélissa 08 1900 (has links)
Cette étude porte sur les différentes formalisations du sens linguistique dans le cadre de la théorie Sens-Texte (TST) ; elle s’intéresse notamment à la représentation sémantique, la représentation la plus importante dans la modélisation du sens d’énoncés et d’unités lexicales de la langue. Cette étude a trois objectifs : premièrement, décrire trois formalisations de la représentation sémantique existant dans la TST – les réseaux sémantiques, les définitions lexicographiques et les définitions de la BDéf (des définitions très formalisées) ; deuxièmement, identifier les disparités et les décalages entre les formalisations choisies ; troisièmement, proposer des modifications aux formalisations existantes pour réduire au maximum ces disparités. / This study explores the different formalisations of linguistic meaning as encountered in the Meaning-Text Theory (MST) framework. Its main interest is semantic representation, which is the most important representation in the modeling of the meaning of utterances and lexical units. This study has three objectives: first, describing three existing formalisations of semantic representation in the MST – semantic networks, lexicographical definitions, and BDéf definitions (definitions that are extremely formalized); second, identifying the discrepancies between these formalisations; finally, proposing modifications to these formalisations in order to reduce the disparities as much as possible.
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霍奇排名之理論分析 / Theoretic Aspect of HodgeRank陳名秀, Chen, Ming Hsiu Unknown Date (has links)
霍奇排名是在近幾年才運用在排名的一種方法。在大多數現在的資料庫 中,資料庫很龐大,有些甚至會需要網路連結,而且很多會有資料不完整或 是資料不平衡的狀況。我們選擇用霍奇排名這種排名方法來處理可能會遇到 的這些困擾。
這篇論文主要目的是想用運用基本的線性代數來研究霍奇排名和推導組合霍奇理論。 / HodgeRank is a method of ranking that is new in recent years. In most of modern datasets, the amount of data is very large, some also need the internet connection, and plenty of them have the feature that incomplete or imbalanced. We use the method of HodgeRank to deal with these difficulties.
This thesis is primary using elementary linear algebra to survey HodgeRank and deduce the combinatorial Hodge Theorem.
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