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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.
81

Development and Validation of a Computational Musculoskeletal Model of the Elbow Joint

Fisk, Justin Paul 01 January 2007 (has links)
Musculoskeletal computational modeling is a versatile and effective tool which may be used to study joint mechanics, examine muscle and ligament function, and simulate surgical reconstructive procedures. While injury to the elbow joint can be significantly debilitating, questions still remain regarding its normal, pathologic, and repaired behavior. Biomechanical models of the elbow have been developed, but all have assumed fixed joint axes of rotation and ignored the effects of ligaments. Therefore, the objective of this thesis was to develop and validate a computational model of the elbow joint whereby joint kinematics are dictated by three-dimensional bony geometry contact, ligamentous constraints, and muscle loading.Accurate three-dimensional bone geometry was generated by acquiring CT scans, segmenting the images to isolate skeletal features, and fitting surfaces to the segmented data. Ligaments were modeled as tension-only linear springs, and muscle were represented as force vectors with discrete attachment points. Bone contact was modeled by a routine which applied a normal force at points of penetration, with a force magnitude being a function of penetration depth. A rigid body dynamics simulator was used to predict the model's behavior under particular external loading conditions.The computational model was validated by simulating past experimental investigations and comparing results. Passive flexion-extension range of motion predicted by the model correlated exceptionally well with reported values. Bony and ligamentous structures responsible for enforcing motion limits also agreed with past observations. The model's varus stability as a function of elbow flexion and coronoid process resection was also investigated. The trends predicted by the model matched those of the associated cadaver study.This thesis successfully developed an accurate musculoskeletal computational model of the elbow joint complex. While the model may now be used in a predictive manner, further refinements may expand its applicability. These include accounting for the interference between soft tissue and bone, and representing the dynamic behavior of muscles.
82

Framtagning av joystick för barn 0-3 år

Sandström, Evelina, Wiberg, Alexandra January 2018 (has links)
No description available.
83

High speed flywheel design : Using advanced composite materials

Kamf, Tobias January 2012 (has links)
This thesis is a part of a larger project that focuses on the development of a highspeed, high energy flywheel using both high-tech composites and levitating magneticbearings alongside a custom made, permanent magnetized generator built into theflywheel itself. The goal of the project is then to integrate this flywheel into anelectrical vehicle.The main focus of this thesis is the composite material. The composite is to be usedas a shell around the flywheel rotor. This composite shell fills two purposes. The firstis to act as the main energy carrying material, storing above 75% of the total energy inthe flywheel. The second purpose it to strengthen the machine, holding it together.This so that higher speeds than normally possible can be achieved, with the goal beingset to 30 000rpm.In order to be able to design the composite shell correctly a method of calculating theload stresses had to be developed. This was done by the creation of a Matlabprogram, named Spin2Win, capable of calculating the stresses inside a compositemetal hybrid flywheel. Using said Matlab code, combined with modelling andsimulations from SolidWorks, a fully-fledged flywheel was designed complete withdrawings and material specifications.The composite analysis surprisingly shows that the best combination of compositematerials is a mixture of both high strength carbon fibres alongside softer glass fibrescoupled with the weight of the central core. This allowed for control of the radialstresses which was shown to otherwise be the limiting factor when designing rotatingcomposite materials.One of the most interesting, and perhaps even unique, parts of the design is that theelectrical machine has been integrated into the flywheel’s composite shell. Having thetwo entities working together in order to control the radial stresses in thecomposite, by utilizing the weight of the permanent magnets.
84

Technické aspekty použití 3D tisku ve výuce na ZŠ / Technical aspects of the use of 3D printing in the education at elementary school

CVRČEK, Tomáš January 2016 (has links)
This thesis in the beginning deals with the history of 3D printing and its development. For better understanding the nature of 3D printing are the significant technologies that includes. Professional part includes work with the printer MakerBot Replicator 2X. Mechanical parts of the device are analyzed together with the operating software MakerBot DesktopThe following chapter is dealing with the limits and restrictions when it is printed on said 3D printer, except that describes important aspects when working on the printer. For the creation of electronic models are suggested appropriate programs for use in elementary school. A significant milestone is forming the problems of 3D printing, which can serve as a guide for the elimination of print quality problems, malfunctioning of 3D printers and others. Interesting models are designed for teaching physics and working activities that the students facilitate understanding of the substance of the response and act as activating element within lesson. It was created a list of important sites where you can find models suitable not only for teaching in elementary schools, but also for other purposes. The last chapter deals with the economic aspect of 3D printing.
85

Mezipředmětové vztahy na úrovni plánovaného kurikula ve vzdělávacích oblastech Matematika a její aplikace a Člověk a svět práce. / Interdisciplinary relationships at the level of the planned curriculum in the educational areas of Mathematics and its Applications and Man and the World of Work.

BARTOŇ, Petr January 2016 (has links)
The goal of my diploma thesisis to create a set of tasks for education at basic school. This thesis is especially focused on realization of tasks from practice.In theoretical part I deal with complex of inter-subject relations between described branches in this work, computer support, selection of 3D CAD programmes at basic school with regard to price availability and technical designing (drawing). The practical part is focused on working papers. This part allows the construction of product using the calculation of word task. This calculation makes theimage about that product easier and allows creation of model in the CAD programme and the final production. This thesis is checked up by pupils in ninth degree of basic school. The fundamental part of this work forms appendix of working papers, which are prepared for education. I consider the approachof solving the tasks for pupils at second degree of basic school to be innovative.
86

Analýza působení spínacího systému jističe nn na tepelnou spoušť / Analysis of effect of the switching system of low voltage breaker on the thermal tripping unit

Liščák, Jiří January 2018 (has links)
Main aims of this master’s thesis are executing measurements and simulations on low voltage circuit breaker and analyzing effect of the switching mechanism on the thermal tripping unit. There are two programs used for simulations in this thesis ANSYS and SolidWorks Flow Simulation. As another part of the thesis were done two types of tests. First was electrical durability test and second one was warming test. In this thesis were measured values of warming on whole current path not only on thermal tripping unit.
87

3D tiskárna typu Delta / Delta type of 3D printer

Němec, Radek January 2019 (has links)
This master thesis is about design and construction of FDM delta 3D printer which consists of 32-bit electronics, magnetics printer head and other necessary peripheries. Opening chapters of this thesis are about theory of 3D printing and its methods with description of FDM 3D printers and summarization of FDM plastic materials used for 3D printing. The next part is about used electronics and problematic of heat transfer. The main part of this thesis describes design and construction of 3D printer and its necessary peripheries, which includes creation of its 3D model and application for 32bit controller. 3D model of delta 3D printer and its heating components was created in CAD software SolidWorks. The last part includes description of commissioning and calibration of delta 3D printer with summarization of economic aspects of its creation.
88

Návrh domácí brány pro zařízení IoT využívající technologii Z-Wave / Home gate for IoT devices using Z-Wave technology

Resler, Tomáš January 2019 (has links)
This dissertation deals with the platform Z-Wave. This platform tries to create an universal system for smart home. The theoretical part of the work describes in details the platform itself as well as the applicable libraries for programming of applications and the available equipments. The practical part presents the new custom gateway. The hardware of this gateway is designed with utilization of the Z-Wave module, Raspberry Pi 3 microcomputer, touchscreen, powerbank and the body of the system. The body has been designed in the Solid Works CAD system and printed on a 3D printer. The needed firmware was loaded into the Z-Wave module ZM5304 and this module has been interconnected with the Raspberry Pi 3 through the printed circuit board of the custom design. The gateway drives OpenZWave network through the new own application written with help of Python wrapper of the library OpenZWave and other open source components. The part of the work is also the list and description of the alternative commercial gateways available on the Czech market.
89

Studie možností využití Teslovy turbíny jako zdroj energie / Study of the possibility of using Tesla's turbine as a source of energy

Šedina, Martin January 2020 (has links)
The master thesis deals with the currently used types of water turbines and next part of the thesis deals with the theory of Tesla turbine. The theoretical part discusses water wheels, water turbines with their types and models which are described in the work. The thesis also discusses the construction of the Tesla turbine, its possibilities of using, inside principles and information about Tesla´s patent. The practical part contains the design of the Tesla turbine with modifications for increasing efficiency. The thesis describes production and assembly of turbine and the technology used for production of the turbine. There is also described how the turbine was measured and there are results of measurements of the turbine.
90

Analýza nadproudové spouště pomocí MKP / FEM analysis of overcurrent trip unit

Makki, Zbyněk January 2010 (has links)
The aim of the project was to prepare the given model of the current path in the environment of the SolidWorks programme, in order to simulate the flow path in the environment of the Ansys programme, where there was calculated the distribution of current density,voltage drops and heat loss on the the specified current track according to specified conditions. The obtained results are analyzed at the conclusion of this work.

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