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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Programovatelná osvětlovací soustava pro optický mikroskop / Programmable illuminating system for an optical microscope

Lošťák, Martin January 2008 (has links)
A programmable illuminating system (PIS) uses a commercial multimedia projector together with a suitable optical relay system in order to illuminate specimens under microscope with transmitted light. The theoretical part of the diploma thesis describes some methods used in the optical transmission microscopy. All of these methods employ physical masks placed in the condenser front focal plane. In the case of the traditional methods the masks are used to enhance contrast (e.g. dark-field illumination) and resolution (oblique illumination). One of the methods (a condenser with rotating aperture) provides the information about the three-dimensionality of the specimen. The next part of the thesis contains the theory and the basic classification of the illuminating systems used in the optical transmission microscopy. An optical and mechanical design of the optical relay system used for PIS is introduced. The experimental part shows the results made with two different PIS arrangements. It was shown on two different specimens that the PIS provides the same illumination as the classical methods. It was also proved that the PIS can simulate the rotating aperture in the condenser front focal plane and thus to give the information about the three-dimensionality of the specimen. Some new static and dynamic illuminating methods were introduced.
142

«Por no echar la soga tras el caldero» : Un análisis de la traducción al sueco de la novela Lazarillo de Tormes / «Por no echar la soga tras el caldero» An analysis of the translation to Swedish of the novel Lazarillo de Tormes

Arciniegas, Sara January 2020 (has links)
Traducir textos antiguos es un desafío para un traductor, porque además de ser competente en las lenguas tratadas, hay que poder interpretar el contexto cultural del texto original y reproducirlo para los lectores del texto meta. En esta tesina se ha analizado una traducción al sueco de la novela antigua La vida de Lazarillo de Tormes y de sus fortunas y adversidades, de los traductores Lars Axelsson y Margareta Marin. El objetivo fue analizar cómo los traductores han superado los problemas y dificultades que se pueden encontrar al traducir un texto antiguo, y qué fue el resultado de una traducción así. Se ha usado una metodología para la traducción de Vinay y Darbelnet y la teoría de skopos de Vermeer, para llevar a cabo el análisis. En el resultado se ha visto que la traducción oblicua fue el método más usado, y el texto meta se diferencia del texto original en varias maneras. A pesar de esto, los traductores han logrado conservar la esencia del texto original en el texto meta. / Translating ancient texts is a challenge for the translator. It is not enough to be competent in the languages in question, it is also necessary to be able to interpret the cultural context and reproduce it for the readers of the target text. In this thesis, the Swedish translation of La vida de Lazarillo de Tormes y de sus fortunas y adversidades by the translators Lars Axelsson y Margareta Marin has been analyzed. The purpose was to analyze how the translators have overcome the problems and difficulties that can be encountered whilst translating an ancient text, and what was the result of such translation. A methodology for translation by Vinay and Darbelnet and the skopos theory by Vermeer have been used to carry out the analysis. As a result, it was seen that oblique translation was the most common method, and the target text is different than the original text in many ways. Despite this, the translators have succeeded with conserving the essence of the original text in the target text.
143

Exploring Surface Silanization and Characterization of Thin Films: From Surface Passivation to Microstructural Characterization of Porous Silicon/Silica, and Exploratory Data Analysis of X-Ray Photoelectron Spectroscopy Images

Moeini, Behnam 21 June 2023 (has links) (PDF)
Surface chemistry plays a key role in science and technology because materials interact with their environments through their surfaces. Understanding surface chemistry can help alter/improve the properties of materials. However, surface characterization and modification often require multiple characterization and synthesis techniques. Silicon/silica-based materials are technologically important, so studying their surface properties can enable future advancements. In this dissertation, I explore surface modification and characterization of different types of Si/SiO2 thin films, including silicon wafers, fused silica capillary columns, and oblique angle sputtered Si/SiO2 thin films. In Chapters 2-5, I first present a method to rapidly silanize silica surfaces using a gas-phase synthesis that employs a small aminosilane that passivates/deactivates silicon wafers and the inner surfaces of capillary columns. This deposition takes place in a flow-through, atmospheric pressure, gas-phase reactor. This surface modification results in a significant decrease in the number of free surface silanols, which was confirmed by high-sensitivity low energy ion scattering (HS-LEIS), X-ray photoelectron spectroscopy (XPS), and spectroscopic ellipsometry (SE). I then show that this silanization inhibits atomic layer deposition (ALD) of zinc oxide (ZnO), which is an important optical thin film material. Finally, I performed in-depth characterization of thin films of oblique angle deposited porous Si/SiO2. These films have been used as the active coatings in solid phase microextraction (SPME) devices. The characterization and analysis in this study were mainly by scanning transmission electron microscopy (STEM) and various computational microstructural characterization techniques, e.g., two-point statistics. The rest of my dissertation focuses on XPS data analysis and interpretation. I first show box plots as a simple graphical tool for determining overfitting in XPS peak fitting. I next present a series of chemometrics/informatics analyses of an XPS image dataset from a patterned silicon surface with different oxide thicknesses. This dataset was probed via an initial, graphical analysis of the data, summary statistics with a focus on pattern recognition entropy (PRE), principal component analysis (PCA), multivariate curve resolution (MCR), and cluster analysis (CA).
144

The Use of Self Survey Instrument (UoS-SI): An Exploratory Factor Analysis and Reliability Analysis

Traxler, Jennifer L. 30 August 2022 (has links)
No description available.
145

The Growth of Columnar Thin Films and Their Characterization Within the Visible and Near Infrared Spectral Bands

Booso, Benjamin David 05 May 2010 (has links)
No description available.
146

Authentic Leadership can be Measured Within Organizations Through the use of Leadership Assessment Centers: A Factor Analytic Study of the Authentic Leadership Construct

Smith, Nicole K. 19 December 2016 (has links)
No description available.
147

Transmission problems for Dirac's and Maxwell's equations with Lipschitz interfaces

Axelsson, Andreas, kax74@yahoo.se January 2002 (has links)
The aim of this thesis is to give a mathematical framework for scattering of electromagnetic waves by rough surfaces. We prove that the Maxwell transmission problem with a weakly Lipschitz interface,in finite energy norms, is well posed in Fredholm sense for real frequencies. Furthermore, we give precise conditions on the material constants ε, μ and σ and the frequency ω when this transmission problem is well posed. To solve the Maxwell transmission problem, we embed Maxwell’s equations in an elliptic Dirac equation. We develop a new boundary integral method to solve the Dirac transmission problem. This method uses a boundary integral operator, the rotation operator, which factorises the double layer potential operator. We prove spectral estimates for this rotation operator in finite energy norms using Hodge decompositions on weakly Lipschitz domains. To ensure that solutions to the Dirac transmission problem indeed solve Maxwell’s equations, we introduce an exterior/interior derivative operator acting in the trace space. By showing that this operator commutes with the two basic reflection operators, we are able to prove that the Maxwell transmission problem is well posed. We also prove well-posedness for a class of oblique Dirac transmission problems with a strongly Lipschitz interface, in the L_2 space on the interface. This is shown by employing the Rellich technique, which gives angular spectral estimates on the rotation operator.
148

Contribution à létude du peptide de fusion et du domaine transmembranaire des glycoprotéines de fusion virales de classe 1 / Contribution to the study of the fusion peptide and the transmembrane domain of class 1 viral fusion glycoproteins

Lorin, Aurélien 09 October 2007 (has links)
Les glycoprotéines de fusion virales de classe 1 contrôlent la fusion entre lenveloppe virale et la membrane cellulaire. Ces glycoprotéines présentent une extrémité N-terminale indispensable à la fusion, le peptide de fusion. Les peptides de fusion sont capables dinduire à eux seuls la fusion de membranes in vitro. Dans cette étude, nous avons dabord analysé les peptides de fusion de gp41 du HIV et de gp30 du BLV. Ces deux peptides de fusion sont des peptides obliques : ils sinsèrent obliquement dans la membrane sous forme hélicoïdale. Nos études ont montré une relation entre la capacité de ces deux peptides de fusion à sinsérer obliquement dans la membrane et la capacité de leurs glycoprotéines de fusion à induire la fusion. Dans le cas du BLV, nous avons également montré une relation entre lobliquité du peptide de fusion et sa fusogénicité. Cette relation obliquité-fusogénicité a été utilisée pour prédire avec succès la région minimale des deux peptides de fusion suffisante pour induire une fusion significative in vitro, qui correspond respectivement aux douze et aux quinze premiers acides aminés de gp41 et gp30. Nos résultats montrent également que le peptide caméléon, un peptide de novo avec une structure labile, sinsère obliquement dans la membrane et induit la fusion in vitro. Le fait que ce peptide fasse partie des peptides obliques, comme les peptides de fusion du HIV et BLV, renforce lhypothèse dun lien entre la fusogénicité des peptides de fusion et leur flexibilité structurale. De nombreuses études réalisées sur les glycoprotéines de fusion de classe 1 indiquent que le domaine transmembranaire intervient également dans la fusion virale. Ce domaine doit être suffisamment long pour que la fusion soit complète. Dans ce travail, nous avons montré quun peptide transmembranaire modèle, le peptide KALR, est capable de sinsérer et dinduire la fusion de liposomes in vitro. En comparant les résultats de modélisation moléculaire avec ceux de FTIR et ceux de la fusion de phase lipidique/perméabilisation de liposomes, nous avons également montré que le taux dinsertion membranaire et la fusogénicité de KALR dépendent de la longueur de son cur hydrophobe. En effet, le taux dinsertion de KALR dans la membrane est beaucoup plus important lorsquil contient un cur hydrophobe lui permettant de traverser entièrement la membrane. Dans cette situation, KALR est capable dinduire la déstabilisation et la fusion de membranes alors que lorsque son cur hydrophobe est trop court pour lui permettre de traverser la membrane, il en est incapable. Ces résultats ont permis dapporter des éléments de compréhension des mécanismes intervenant lors de la fusion induite par les glycoprotéines de fusion virales. / Abstract: Class 1 fusion glycoproteins of viruses are involved in the fusion between viral envelope and cell membrane. The N-terminal extremity of these glycoproteins, called fusion peptide, is essential for fusion. Fusion peptides are able to induce by themselves in vitro membrane fusion. Firstly, we analysed fusion peptides of HIV-1 gp41 and BLV gp30. These two peptides are tilted peptides: they insert obliquely in the membrane when helical. Our studies showed a correlation between the ability of these two fusion peptides to insert obliquely in the membrane and the ability of whole glycoproteins to induce fusion. For BLV, a relationship between the obliquity of the fusion peptide and its fusogenicity was also observed. This obliquity/fusogenicity relationship was used to successfully predict the minimal region of the two fusion peptides sufficient to induce significant in vitro fusion. The minimal fusion peptide corresponds respectively to the twelve and to the fifteen first residues of gp41 and gp30. Our results also showed that the chameleon peptide, a de novo peptide with structural flexibility, inserts obliquely into the membrane and induces in vitro fusion. The fact that this peptide is a tilted peptide, like fusion peptides of HIV-1 and BLV, confirms the hypothesis of a relationship between the fusion peptides fusogenicity and their structural flexibility. A lot of studies on class 1 fusion glycoproteins of viruses indicate that the transmembrane domain is also directly involved in the viral fusion. Glycoproteins must have a domain long enough to induce complete fusion. In this study, we showed that a model transmembrane peptide, KALR peptide, is able to insert into membranes and to induce their fusion. By comparing molecular modelling results with those of FTIR, of liposomes lipid-mixing and of liposomes leakage, we also showed that the insertion rate into the membranes and the fusogenicity of KALR depend on the length of its hydrophobic core. Indeed, the insertion rate of KALR into the membrane is greatly larger when it contains a hydrophobic core long enough to allow the peptide to traverse the membrane. In this situation, KALR is able to destabilize membranes and to induce their fusion, while when it is too short to match the membrane, it is unable to induce fusion. These results allow to better understanding mechanisms involved in the fusion induced by viral fusion glycoproteins.
149

The use of Inverse Neural Networks in the Fast Design of Printed Lens Antennas

Gosal, Gurpreet Singh January 2015 (has links)
In this thesis the major objective is the implementation of the inverse neural network concept in the design of printed lens (transmitarray) antenna. As it is computationally extensive to perform full-wave simulations for entire transmitarray structure and thereafter perform optimization, the idea is to generate a design database assuming that a unit cell of the transmitarray is situated inside a 2D infinite periodic structure. This way we generate a design database of transmission coefficient by varying the unit cell parameters. Since, for the actual design, we need dimensions for each cell on the transmitarray aperture and to do this we need to invert the design database. The major contribution of this thesis is the proposal and the implementation of database inversion methodology namely inverse neural network modelling. We provide the algorithms for carrying out the inversion process as well as provide check results to demonstrate the reliability of the proposed methodology. Finally, we apply this approach to design a transmitarray antenna, and measure its performance.
150

Návrh optimálního průběhu montáže strojů "Multinip" ve vybraném podniku / Proposal for Optimizations the Process Machine Bulding Conditions in Company

Valouch, Jiří January 2008 (has links)
Making of an analysis of the assembly process. Presentation of safe and efficient assembly with the help of platforms or scaffolding for all types of machines according to the working width. Choosing the most suitable alternative of machine assembly. Suggestion about the assembly workstation's placement in a hall. Storage and logistics. Advantages of the chosen solution. Summary of the conclusions.

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