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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.
91

Most na dálnici / Bridge on a highway

Juřicová, Markéta January 2016 (has links)
Diploma thesis deals with design of oblique highway bridge over the valley brook Pustějovského. Two-joist girder of three spans is selected from the three proposed variants. Static calculation is drafted according to European norem- Eurocode. The structure is designed and assessed for limit states temporary and permanent load conditions. And a further is elaborated detailed and well-arranged drawing documentation, visualization of bridge and construction procedure.
92

Oblique Angle Deposition of Thin Films – Theory, Modelling, and Application

Grüner, Christoph 24 July 2019 (has links)
With the aim to gain a deeper understanding of the role of the angle of incidence in physical vapor deposition, experimental, and computer-based studies were conducted. Electron beam evaporation and ion beam sputtering were used as deposition methods. The materials germanium, silicon, and molybdenum were deposited at different incidence angle, different temperatures and varied residual gas atmospheres. Established models could not be used to adequately explain the obtained relations between morphological parameters, as the tilt angle, with the incidence angle. To investigate the interplay of self-shadowing and competitive growth, an on-lattice simulation was developed. Care was taken to avoid any artificial anisotropy. Comparison with an, additionally developed, off-lattice simulation was used to verify this. Based on the made observations, an analytical model was deduced that combines the material properties and the deposition conditions into a single parameter. The predictions of this model were verified for the experimental observations, the results of the computer simulations, and on literature data. In the last part of the thesis, methods are shown that facilitate to modify the properties of the obliquely deposited thin films to fit requirements of various applications. This includes in situ doping of silicon nanostructures, creation of core-shell structures, as well as biochemical surface functionalization of silver nanostructures. On the example of the latter, various bio-sensing applications are presented.:1 MOTIVATION 7 2 BASIC CONCEPTS 9 2.1 Physical vapor deposition (PVD) 9 2.2 Deposition at oblique angles 14 2.3 Controlling the thin film morphology 16 3 EXPERIMENTAL METHODS 19 3.1 Sample preparation 19 3.2 Characterization techniques 32 4 EXPERIMENTAL RESULTS 37 4.1 Columnar structure and evolutionary selection 37 4.2 Tilt angles and density 42 4.3 Fan angles 45 4.4 Relevance of beam divergence 47 4.5 Summary 50 5 SIMULATION 53 5.1 Introduction 53 5.2 Off-lattice approach 54 5.3 On-lattice approach 59 5.4 Further applications of the on-lattice simulation 64 5.5 Other aspects 72 5.6 Summary 76 6 OBLIQUE ANGLE DEPOSITION MODEL 77 6.1 Semi-Empirical models 77 6.2 Tanto’s fan model 78 6.3 Development of the Competition Model 80 6.4 Verification of the model 84 6.5 Summary 89 7 FILM OPTIMIZATION FOR APPLICATIONS 91 7.1 Boron doped Si nanostructures 91 7.2 Surface functionalization for biosensors 95 7.3 Core-shell structures by pulsed electrodeposition 101 7.4 Summary 105 8 SUMMARY 107 9 BIBLIOGRAPHY 109 10 LIST OF ABBREVIATIONS 121 11 ACKNOWLEDGEMENTS 123 APPENDIX 125 PUBLICATION LIST 131 SELBSTSTÄNDIGKEITSERKLÄRUNG 133 / Mit dem Ziel ein besseres Verständnis des Einflusses des Einfallswinkels in der physikalischen Gasphasenabscheidung zu erreichen, wurden experimentell realisierte und am Computer simulierte Dünnschichten untersucht. Als Abscheidetechniken kamen sowohl Elektronenstrahl-Verdampfen als auch Ionenstrahl-Zerstäubung zum Einsatz. Es wurden die Materialien Germanium, Silicium und Molybdän verwendet, die bei verschiedenen Einfallswinkeln, verschiedenen Substrattemperaturen und variiertem Restgas abgeschieden wurden. Die beobachteten Zusammenhänge, von bspw. kolumnarer Verkippung und Einfallswinkel, konnten nicht mit den etablierten Modellen in Einklang gebracht werden. Um das genaue Zusammenspiel von Abschattung und Konkurrenz-Wachstum zu verstehen, wurde eine „on-lattice“ Computersimulation entwickelt, mit dem besonderen Augenmerk auf die Vermeidung von gitterbasierten Anisotropien. Dies wurde durch Vergleich mit einer, ebenfalls entwickelten, „off-lattice“ Simulation sichergestellt. Ausgehend von den beobachteten Effekten konnte ein analytisches Modell entwickelt werden, welches die Materialeigenschaften und Abscheidebedingungen in einen einzigen Parameter vereint. Die Vorhersagen des Modells wurden an den hergestellten Schichten, den Computersimulationen und an Literaturdaten verifiziert. Abschließend werden Methoden aufgezeigt, die schräg abgeschiedenen nanostrukturierten Schichten verschiedenen Anwendungen anzupassen. Dies umfasst die in situ Dotierung von Siliciumnanostrukturen, die Erzeugung von Kern-Schale-Strukturen, sowie die biochemische Oberflächenfunktionalisierung von Silbernanostrukturen. Am Beispiel der letztgenannten werden verschiedene Anwendungen in der Biosensorik detaillierter vorgestellt.:1 MOTIVATION 7 2 BASIC CONCEPTS 9 2.1 Physical vapor deposition (PVD) 9 2.2 Deposition at oblique angles 14 2.3 Controlling the thin film morphology 16 3 EXPERIMENTAL METHODS 19 3.1 Sample preparation 19 3.2 Characterization techniques 32 4 EXPERIMENTAL RESULTS 37 4.1 Columnar structure and evolutionary selection 37 4.2 Tilt angles and density 42 4.3 Fan angles 45 4.4 Relevance of beam divergence 47 4.5 Summary 50 5 SIMULATION 53 5.1 Introduction 53 5.2 Off-lattice approach 54 5.3 On-lattice approach 59 5.4 Further applications of the on-lattice simulation 64 5.5 Other aspects 72 5.6 Summary 76 6 OBLIQUE ANGLE DEPOSITION MODEL 77 6.1 Semi-Empirical models 77 6.2 Tanto’s fan model 78 6.3 Development of the Competition Model 80 6.4 Verification of the model 84 6.5 Summary 89 7 FILM OPTIMIZATION FOR APPLICATIONS 91 7.1 Boron doped Si nanostructures 91 7.2 Surface functionalization for biosensors 95 7.3 Core-shell structures by pulsed electrodeposition 101 7.4 Summary 105 8 SUMMARY 107 9 BIBLIOGRAPHY 109 10 LIST OF ABBREVIATIONS 121 11 ACKNOWLEDGEMENTS 123 APPENDIX 125 PUBLICATION LIST 131 SELBSTSTÄNDIGKEITSERKLÄRUNG 133
93

Width of maxillary lateral incisors and its role in the perception of esthetics amongst patients and clinicians

Allred, Chad 01 January 2013 (has links)
A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry. Objective: This study aimed to determine and compare the esthetic preference of the general public, dentists, orthodontists and prosthodontists in relation to the width of the most anatomically variable tooth in the mouth, the maxillary lateral incisor. Background: The general public today places more importance on facial esthetics than they have in the past and their esthetic preferences are evolving. The smile is a main feature of facial esthetics and its attractiveness is based in part on the size and proportion of the anterior teeth. The lateral incisors are the most variable in size and there is a continuing debate in the literature with conflicting reports about how wide they should be in proportion to their neighboring teeth. Methods: Two sets of seven images of frontal and oblique (three-quarter) smile views were created with Adobe Photoshop Elements 10 by morphing two "Master Smile" images. The seven images within each set had different width proportions of lateral incisors. However, they were identical in every other aspect such as differences in lip thickness or tooth shape to diminish the impact of compounding variables between photographs. A link to an online survey was distributed by email to four groups: laypeople, general dentists, orthodontists and prosthodontists. Subjects taking the survey ranked the seven photographs in each set from the most to the least esthetic based on their personal preference. The results were studied to ascertain whether the general public has an esthetic preference in the width of lateral incisors and, if that preference exists, whether it is different from that of trained dental professionals. Results: In a frontal view of a smile, the global preference for the width of a lateral incisor falls into the range of 62.5-72.5% of the width of the central incisor. The probability that the most preferred choice is 67.5% or greater is 66%. In the frontal view there was no statistically significant difference between professions. Non-Hispanic white respondents preferred slightly more narrow laterals than other ethnicities in the frontal view. Respondents older than forty preferred slightly wider laterals than respondents under forty in the frontal view. In the oblique view, there was a 69% probability that the most preferred choice was the largest option: a lateral incisor 91.5% of the width of the visible width of the central incisor. In the oblique view, the three groups of dental professionals were more likely than the general public to select a wider incisor as the most esthetic option. Conclusion: Preference for smile attractiveness can be significantly influenced by the width of lateral incisors in a frontal and oblique view. Orthodontist, general dentists, and prosthodontists were shown to be in general agreement with the public in preferring a wider lateral incisor viewed from a frontal smile. In an oblique view, their professions had a statistically significant impact on the difference between their choices compared to laypeople in that they preferred a slightly wider lateral incisor. All groups preferred significantly wider laterals than is proscribed by the Golden Proportion.
94

Využití obecně orientovaných snímků v geoinformatice / Generally oriented images in geoinformatics

Káňa, David January 2013 (has links)
This thesis deals with methods and algorithms used in computer vision for fully automatic reconstruction of exterior orientation in ordered and unordered sets of images captured by digital calibrated cameras without prior informations about camera positions or scene structure. Existing methods for key points detection, matching and relative orientation of images are described. Methods and strategies for merging submodels into global reconstruction including complex bundle adjustment are proposed. This thesis also adresses issues of direct and indirect georeferencing of images and orthophoto production problems. An outline related to technology of the capturing images by multiple camera systems is given and possible usage of oblique images is described, especially technology of the automatic 3D models texturing and measurements in one image using restrictive geometric conditions.
95

Study on Nonlinear Acceleration of Electrons by Oblique Whistler Mode Waves / 斜め伝搬ホイッスラーモード波による非線形電子加速に関する研究

Hsieh, Yikai 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21071号 / 工博第4435号 / 新制||工||1689(附属図書館) / 京都大学大学院工学研究科電気工学専攻 / (主査)教授 大村 善治, 教授 松尾 哲司, 准教授 小嶋 浩嗣 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
96

Automated mapping of oblique imagery collected with unmanned vehicles in coastal and marine environments

Freeman, Jacob B. 12 May 2023 (has links) (PDF)
Recent technological advances in unmanned observational platforms, including remotely operated vehicles (ROVs) and small unmanned aerial systems (sUAS), have made them highly effective tools for research and monitoring within marine and coastal environments. One of the primary types of data collected by these systems is video imagery, which is often captured at an angle oblique to the Earth’s surface, rather than normal to it (e.g., downward looking). This thesis presents a newly developed suite of tools designed to digitally map oblique imagery data collected with ROV and sUAS in coastal and marine environments and quantitatively evaluates the accuracy of the resultant maps. Results indicate that maps generated from oblique imagery collected with unmanned vehicles have highly variable accuracy relative to maps generated with imagery data collected with conventional mapping platforms. These results suggest that resultant maps have the potential to match or even surpass the accuracy of maps generated with imagery data collected with conventional mapping platforms but realizing that potential is largely dependent upon careful survey design.
97

Faktorer som kan påverka den optimala bildkvaliteten vid mammografiundersökningar : En allmän litteraturöversikt / Factors that can affect the optimal image quality in mammography examinations : A general literature review

Mikko, Linnéa, AI-Hasani, Amna January 2022 (has links)
Abstrakt Inledning: I Sverige erbjuds alla kvinnor mellan 40-74 år möjlighet till att genomgå en hälsokontroll (screening) av sina bröst. Syftet med mammografiscreening är att hitta patologi så tidigt som möjligt för att kunna tillgodose en gynnsam behandling och för att förhindra dödlig utgång. Röntgensjuksköterskan har en viktig roll i den bilddiagnostiska utredningen. En av röntgensjuksköterskans uppgifter är att framställa röntgenbilder med optimal bildkvalitet samtidigt som patientsäkerheten måste beaktas. Syfte: Syftet var att beskriva faktorer som kan påverka den optimala bildkvaliteten vid mammografiundersökningar. Metod: För att få svar på syftet genomfördes en allmän litteraturöversikt. Vetenskapliga artiklar letades i databaserna PubMed och Cinahl. 15 artiklar sammanställdes och analyserades sedn i tre kategorier. Resultat: Analysen av artiklarna visade på att det finns flera faktorer som kan inverka på den optimala bildkvaliteten vid mammografiundersökningar. Analysen presenterade tre kategorier såsom patientrelaterade aspekter, tekniska parametrar och röntgensjuksköterskans betydelse. Slutsats: Röntgensjuksköterskans kunskaper och kännedom om vilka faktorer som kan inverka på bildkvaliteten är viktig för att minimera brister i bildkvaliteten. För att kvalitetsförbättra mammografiundersökningarna samt bibehålla kunskap krävs kontinuerlig träning och utbildning.
98

Saccadic eye movement measurements in the normal eye: Investigating the clinical value of a non-invasive eye movement monitoring apparatus.

Kavasakali, Maria January 2005 (has links)
Clinicians are becoming increasingly aware of the effect of various pathologieso n the characteristicso f saccadice ye movements.A s such, an efficient and non-invasivem eano f measuringe ye-movementisn a clinical environmenti s of interest to many. The aim of this thesis is to investigate the clinical application of a non-invasive eye movement recording technique as a part of a clinical examination. Eye movements were measured using an IRIS 6500 infrared limbal eye tracker, which we customized for the direct recording of oblique eye movements as well as horizontal and vertical. Firstly, the eye-tracker itself was assessed. Visually normal observers made saccadic eye movements to a 10' stimulus in eight directions of gaze. Primary (ANOVA) and secondary analyses (mean error less than 5%) resulted in acceptance that averaging four measurements would give a representative measurement of saccadic latency, peak velocity, amplitude and duration. Test-retest results indicated that this technique gives statistically (± 1.96*STDEVDifference) repeatable responses. Severalf actors that could potentially influence clinically basedm easureso f eye-movementsw ere examined. These included, the effect of ageing, viewing distances, dioptric blur and cataract. The results showed that saccadic latency and durationa re significantly (p< 0.05) longer in older (60-89 years)o bserversc ompared to younger (20-39 years). Peak velocity and amplitude were not significantly affectedb y the age of the observer.A ll saccadicp arameters( SP) were significantly affected by direction (Chapter 5). The compact nature of this eye movement methodology is obtainable since there is no significant effect on viewing distance (300 cm vs. 49 cm) (Chapter 6). There is also no significant effect of dioptric blur (up to +LOODS) on any of the four SP. In contrast, a higher level of defocus (+3.O ODS)h as a larger probability of interfering with the measurementso f peak velocity and duration (Chapter 7). Saccadice ye-movementsw ere also recorded whilst normally sighted subjects wore cataract simulation goggles. The results suggested that the presence of dense cataract introduces significant increases in saccadic latencies and durations. No effect was found on the peak velocities and amplitudes.T he effect of amblyopiao n SP was also investigatedin order to examine if this methodologyi s able to detectn ormal from abnormalr esponses(i . e. increased saccadicla tencies).T his set of data (Chapter9 ) showedt hat using IRIS 6500, longer than normal latencies may be recorded from the amblyopic eye but no consistent effect was found for the other SP (peak velocity, amplitude, duration). overall, the results of this thesis demonstrateth at the IRIS 6500 eye-tracker has many desirable elements (it is non-invasive; comfortable for the observers and gives repeatable and precise results in an acceptable time) that would potentially make it a useful clinical tool as a part of a routine examination.
99

[en] MODE-MATCHING TECHNIQUE ALONG OBLIQUE SURFACES AND APPLICATIONS TO THE MODELING OF CURVED WAVEGUIDES / [pt] MÉTODO DE CASAMENTO DE MODOS AO LONGO DE SUPERFÍCIES OBLÍQUAS E APLICAÇÕES PARA A MODELAGEM DE GUIAS DE ONDAS CURVADOS

MARCELLO ALVES REIS 24 November 2023 (has links)
[pt] Guias de onda são amplamente utilizados na engenharia de telecomunicações para a transmissão de sinais e construção de filtros e outros dispositivos de micro-ondas. Neste trabalho, apresentamos uma formulação baseada na técnica de casamento de modos (MMT) para a análise de descontinuidades em guias de ondas cilíndricos causadas por curvaturas no eixo longitudinal da linha de transmissão. Apresentamos e validamos uma técnica para análise modal de guias de ondas curvos através da aproximação da curvatura por uma sucessão de superfícies oblíquas por meio de suas matrizes de espalhamento generalizadas (GSMs) extraídas do MMT. A presente abordagem é uma alternativa computacionalmente eficiente para modelar curvaturas em guias de ondas cilíndricos quando comparada às técnicas usuais de força bruta numérica (tais como soluções baseadas em elementos, volumes, ou diferenças finitas). Um algoritmo é apresentado para calcular os elementos da matriz GSM para diferentes configurações de junções de guias de onda. A novidade do presente método consiste em considerar a projeção dos campos eletromagnéticos em superfícies oblíquas para a aplicação do MMT. Apresentamos uma série de resultados numéricos que mostram que a técnica apresentada neste estudo pode garantir resultados com boa acurácia e precisão ao realizar a análise do comportamento modal dos campos eletromagnéticos em descontinuidades provocados por curvaturas. / [en] Waveguides are widely used in telecommunications engineering for transmitting signals and manufacturing filters and other devices in the microwave applications. In this work, we present a formulation based on the mode-matching technique (MMT) for the analysis of discontinuities in cylindrical waveguides caused by curvatures in the longitudinal axis of the transmission line. We present and validate a technique for modal analysis of curved waveguides by approximating the curvature in a succession of oblique surfaces by means of their generalized scattering matrices (GSMs) extracted from the MMT. The present approach is a computationally efficient alternative for modeling curvature in cylindrical waveguides when compared to usual numerical brute force techniques (such as element-based, volumebased, or finite difference solutions). An algorithm is presented to compute the GSM matrix elements for different configurations of waveguide junctions. The novelty of the present method consists in considering the projection of electromagnetic fields onto oblique surfaces for the application of MMT. We present a series of numerical results that show that the technique presented in this study can guarantee results with good accuracy and precision when performing the analysis of the modal behavior of electromagnetic fields at discontinuities caused by curvatures.
100

PMHS Shoulder Stiffness Determined by Lateral and Oblique Impacts

Caupp, Sarah N. 05 September 2014 (has links)
No description available.

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