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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.
171

Přestavba letounu Z 142 s pohonnou jednotkou LYCOMING / Rebuilding an airplane Z 142 with a LYCOMING power unit

Šurkala, Martin January 2017 (has links)
The aim of this master´s thesis is to replace the current engine M 337AK of the aeroplane Zlin 142 for the engine of Lycoming type with an appropriate propeller. Another purpose of the study is the installation of a nose undercarriage of VUT 100 type. The first part of the thesis examines the alternatives of replacement engines. Here the individual engines are compared with regard to their flight characteristics (climbing etc.). The next part presents the calculation of new CG positions, flight envelopes and the load affecting the engine mount. Finally, the last part focuses on the constructional plan for the engine installation and the structural analysis.
172

Pevnostní kontrola a topologická optimalizace dílu podvozku letounu / Strength Analysis and Topology optimization of the aircraft landing gear

Baláš, Martin January 2020 (has links)
This master thesis is about stress analysis of landing gear for accomplishment CS-23 regulation. The first part examines all alternatives of landing gear regarding for accomplishment of regulation. Next part is stress analysis of main and nose landing gear using FEM analysis in MSC Nastran software. Last part of master thesis describes topology optimization of two parts of landing gear.
173

Modifikace přistávacího zařízení letounu Irbis / Modification of the landing gear of the Irbis aircraft

Forman, Tomáš January 2021 (has links)
This master thesis deals with the landing gear rebuild from tail gear to nose gear of the M-4 Irbis aircraft. The first chapter presents the aircraft in its current state and includes some technical data, too. The theoretical information about types of landing gears, its characteristics, pros and cons and the typical representatives for each type of landing gear are mentioned in the second chapter. The third chapter is about landing gear loads that occur during landing and about the load calculation according to UL 2 regulation. The following chapter shows the construction of the new landing gear, including some of the suggested, but not realised, designs. In the fifth chapter, there is a landing gear strength calculation of some of the gear components. The calculation is analytical and then uses FEM. The very last chapter then shows the effect of new landing gear on the centre of gravity in its extreme positions. The chapter also compares aircraft masses with both landing gears.
174

Volba a optimalizace řezných podmínek pro progresivní výrobní technologie / Data selection and optimisation of cutting conditions for progressive production technologies

Krupka, Ondřej January 2014 (has links)
This thesis contains theoretical analysis of optimization methods of cutting conditions for current machining processes with focus on finishing turning. Further focus was put on influences of cutting conditions and other effects on requested quality and roughness of machined surface. The effect of part of these conditions was verified in experimental part. The influence of feed rate and depth of cut on surface roughness and geometrical accuracy was experimentally verified.
175

Návrh podvozku VUT200 TwinCobra / Design of VUT200 TwinCobra landing gear

Novák, Josef January 2015 (has links)
The goal of following master thesis is to design variety of configuration and retraction options of VUT200 TwinCobra landing gear. For each option are a wheel base and a gauge set up by possibility of main landing gear retraction. Next, CS 23 demands and stress analysis are followed. There is a view of twin engine aircraft landing gear disclosed as well.
176

Nasologie: Versuch über eine Wissenschaft des 18. Jahrhunderts

Schneider, Ulrich Johannes 18 February 2015 (has links)
Was war die Nase im 18. Jahrhundert? Wie sah die 'Nasologie' des Zeitalters aus, die der Hannoveraner Arzt Johann Georg Zimmermann (1728-1795) als neue Wissenschaft konzipieren wollte?
177

Evaluating energy-based trait shifts and population level impacts of big brown bats (Eptesicus fuscus) with long-term exposure to Pseudogymnoascus destructans

Simonis, Molly C. 12 May 2022 (has links)
No description available.
178

Automated Multidisciplinary Optimizations of Conceptual Rocket Fairings

Smart, Ronald S. 13 July 2011 (has links) (PDF)
The purpose of this research is to develop and architect a preliminary multidisciplinary design optimization (MDO) tool that creates multiple types of generalized rocket fairing models. These models are sized relative to input geometric models and are analyzed and optimized, taking into account the primary objectives, namely the structural, thermal, and aerodynamic aspects of standard rocket flights. A variety of standard nose cone shapes is used as optimization proof of concept examples, being sized and compared to determine optimal choices based on the input specifications, such as the rocket body geometry and the specified trajectory paths. Any input models can be optimized to their respective best nose cone style or optimized to each of the cone styles individually, depending on the desired constraints. Two proof of concept example rocket model studies are included with varying sizes and speeds. Both have been optimized using the processes described to provide delineative instances into how results are improved and time saved. This is done by optimizing shape and thickness of the fairings while ascertaining if the remaining length downstream on the designated rocket model remains within specified stress and temperature ranges. The first optimized example exhibits a region of high stress downstream on the rocket body model that champions how these tools can be used to catch weaknesses and improve the overall integrity of a rocket design. The second example demonstrates how more established rocket designs can decrease their weight and drag through optimization of the fairing design.
179

Development of an Artificial Nose for the Study of Nanomaterials Deposition in Nasal Olfactory Region

Yerich, Andrew J. 29 November 2017 (has links)
No description available.
180

Acoustic sampling considerations for bats in the post-white-nose syndrome landscape

Barr, Elaine Lewis 27 January 2020 (has links)
Bat populations across North America are either facing new threats from white-nose syndrome (WNS) and wind energy development or have already experienced precipitous declines. Accordingly, researchers and managers need to know how to best monitor bats to document population and distribution changes, as well as where to look for persisting populations. Landscape-scale WNS impacts to summer bat populations are not well understood, and although acoustic monitoring is commonly used to monitor these populations, there is limited information about differences among acoustic detectors and the implications to managers thereof. My objectives were to model the relationship between WNS impact, influence of available hibernacula, and environmental factors for summer nightly presence of three WNS-affected bats and to compare how multiple models of acoustic detectors perform in terms of detection probability and nightly recorded bat activity. I collected acoustic data from 10 study areas across Virginia, West Virginia, Ohio and Kentucky to describe changes in nightly presence of WNS-affected bat species during summer 2017. During the same period of time, I compared five types of acoustic detectors at Fort Knox, Kentucky. My results show the potential efficacy of using a WNS impact-year metric to predict summer bat presence, and highlight which environmental variables are relevant for large-scale acoustic monitoring. Additionally, my findings suggest that each of the detector types tested would suffice for most research and monitoring activities, but standardization of detector type within the scope of a project or study should be encouraged. / Master of Science / Bat populations across North America are either facing new threats from white-nose syndrome (WNS) and wind energy development or have already experienced devastating declines. Accordingly, wildlife biologists need to know how to best monitor bats to document population and distribution changes, as well as where to look for remaining populations. Landscape-scale WNS impacts to summer bat populations are not well understood, and although acoustic technology is commonly used to monitor these populations, there is limited information about differences among acoustic detectors and the implications to managers thereof. My objectives were to model the relationship between WNS impact, influence of available bat hibernation caves, and environmental factors for summer nightly presence of three WNS-affected bats and to compare how multiple models of acoustic detectors perform in terms of detection probability and nightly recorded bat activity. I collected acoustic data from 10 study areas across Virginia, West Virginia, Ohio and Kentucky to describe changes in nightly presence of WNS-affected bat species during summer 2017. During the same period of time, I compared five types of acoustic detectors at Fort Knox, Kentucky. My results show potential viability of a WNS impact-year metric to predict summer bat presence, and highlight which environmental variables are relevant for large-scale acoustic monitoring. Additionally, my findings suggest that each of the detector types tested would suit most research and monitoring activities, but standardization of detector type within the scope of a project or study should be encouraged.

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