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A reconfigurable tactile display based on polymer MEMS technologyWu, Xiaosong 25 March 2008 (has links)
This research focuses on the development of polymer microfabrication technologies for the realization of two major components of a pneumatic tactile display: a microactuator array and a complementary microvalve (control) array. The concept, fabrication, and characterization of a kinematically-stabilized polymeric microbubble actuator (¡°endoskeletal microbubble actuator¡±) were presented. A systematic design and modeling procedure was carried out to generate an optimized geometry of the corrugated diaphragm to satisfy membrane deflection, force, and stability requirements set forth by the tactile display goals.
A refreshable Braille cell as a tactile display prototype has been developed based on a 2x3 endoskeletal microbubble array and an array of commercial valves. The prototype can provide both a static display (which meets the displacement and force requirement of a Braille display) and vibratory tactile sensations. Along with the above capabilities, the device was designed to meet the criteria of lightness and compactness to permit portable operation. The design is scalable with respect to the number of tactile actuators while still being simple to fabricate.
In order to further reduce the size and cost of the tactile display, a microvalve array can be integrated into the tactile display system to control the pneumatic fluid that actuates the microbubble actuator. A piezoelectrically-driven and hydraulically-amplified polymer microvalve has been designed, fabricated, and tested. An incompressible elastomer was used as a solid hydraulic medium to convert the small axial displacement of a piezoelectric actuator into a large valve head stroke while maintaining a large blocking force. The function of the microvalve as an on-off switch for a pneumatic microbubble tactile actuator was demonstrated. To further reduce the cost of the microvalve, a laterally-stacked multilayer PZT actuator has been fabricated using diced PZT multilayer, high aspect ratio SU-8 photolithography, and molding of electrically conductive polymer composite electrodes.
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Magnetic quartz crystal microbalanceYu, George Yang 08 July 2008 (has links)
In this thesis, a new technique for using quartz crystal microbalance (QCM) in magnetic field was explored. This technique would take advantage of the sensitive nature of QCM to vibration changes. The idea is to perturb the QCM vibrations with magnetic materials on it by applying magnetic field. A new instrument called magnetic QCM (MQCM) was constructed to explore this technique.
The thesis contains three bodies of work. The first body describes the development of the MQCM instrument and the demonstration of the technique. The resonance frequency of a QCM with conducting polymer (polyaniline) suspension in poly(ethylene glycol) was observed to increase with increasing applied DC magnetic field. The change in population of free spins through doping with HCl vapor is reflected in increased frequency-field curve magnitude.
The second body of work describes the study of QCM proximity phenomenon discovered during the MQCM instrument development process. When an object approaches a vibrating QCM, the resonant frequency changes. This proximity effect is seen at the distance of 10 mm in air and becomes more pronounced as the distance decreases. This effect depends on the value of quality factor, conductivity of the object, and electrical connection of the object to the QCM electrodes. A simple modified Butterworth van-Dyke model is used to describe this effect. It must be recognized that this effect may lead to experimental artifacts in a variety of analytical QCM applications.
The third body of work describes an improved version of MQCM. The complex geometry such as particle suspension were simplified to alternating stack of ferromagnetic and diamagnetic layers. When magnetic field was applied, changes in the QCM admittance magnitude and phase curves were observed. A mass-equivalent stack of continuous consecutive layers of nickel and gold was also exposed to magnetic field but no changes were observed. Butterworth-van-Dyke model attributed the effect to internal shear friction loss among other losses is modulated by the magnetic field. Quantum effect was considered. However, after examining SEM surface images, the source of acoustic response to magnetic field is more likely from interfacial stresses.
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Cross-Platform Post-Mortem Analysis in a Distributed Continuous Integration SystemKrantz, Karl Johan January 2015 (has links)
This thesis aims to improve the cross-platform reliability of software components tested on distributed CI systems. More specifically, it is centered on extracting crash information from cross-platform crashes. Crash information was generated and parsed on Mac, Linux and Windows. The crash information proved to be valuable for developers in their day-to-day job, especially the raw crash information. However, the graph visualizations that were created out of this information proved to be less than satisfactory for developers.
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UMA PROPOSTA DE ARQUITETURA DE PILHA DE COMUNICAÇÃO EM REDE COM UM NÚMERO REDUZIDO DE CAMADAS / A NOVELL NETWORK STACK ARCHITECTURE WITH REDUCED NUMBER OF LAYERSFreitas, Josué Paulo José de 22 August 2009 (has links)
This work presents a network stack architecture proposal with a reduced number of layers. The reduction in number of layers aim to provided a simpler and efficient communication method to embedded systems by allowing the microprocessor, where usually application is implemented, run just application code and not running code related to network communication. The architetucture was implemented on and FPGA board and show, in average, throughput
results around 27 times better in comparision with a network stack implemented in software and running over an embedded microprocessor. / Este trabalho apresenta uma proposta arquitetura de pilha de comunicação em rede com número reduzido de camadas. A redução do número de camadas visa fornecer um método de
comunicação simples e eficaz para sistemas embarcados permitindo que o microprocessador, onde geralmente a Camada de Aplicação é implementada, execute apenas código de aplicação isentando-se assim de tarefas de comunicação em rede. A arquitetura foi implementada em placa de desenvolvimento FPGA e apresentou, em média, vazão cerca de 27 vezes superior em comparação com uma pilha de comunicação implementada em software e executada sobre um
microprocessador embarcado.
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Réécriture d’arbres de piles et traces de systèmes à compteurs / Ground stack tree rewriting and traces of counter systemsPenelle, Vincent 20 November 2015 (has links)
Dans cette thèse, nous nous attachons à étudier des classes de graphes infinis et leurs propriétés, Notamment celles de vérification de modèles, d'accessibilité et de langages reconnus.Nous définissons une notion d'arbres de piles ainsi qu'une notion liée de réécriture suffixe, permettant d'étendre à la fois les automates à piles d'ordre supérieur et la réécriture suffixe d'arbres de manière minimale. Nous définissons également une notion de reconnaissabilité sur les ensembles d'opérations à l'aide d'automates qui induit une notion de reconnaissabilité sur les ensembles d'arbres de piles et une notion de normalisation des ensembles reconnaissables d'opérations analogues à celles existant sur les automates à pile d'ordre supérieur. Nous montrons que les graphes définis par ces systèmes de réécriture suffixe d'arbres de piles possèdent une FO-théorie décidable, en montrant que ces graphes peuvent être obtenu par une interprétation à ensembles finis depuis un graphe de la hiérarchie à piles.Nous nous intéressons également au problème d'algébricité des langages de traces des systèmes à compteurs et au problème lié de la stratifiabilité d'un ensemble semi-linéaire. Nous montrons que dans le cas des polyèdres d'entiers, le problème de stratifiabilité est décidable et possède une complexité coNP-complète. Ce résultat nous permet ensuite de montrer que le problème d'algébricité des traces de systèmes à compteurs plats est décidable et coNP-complet. Nous donnons également une nouvelle preuve de la décidabilité des langages de traces des systèmes d'addition de vecteurs, préalablement étudié par Schwer / In this thesis, we study classes of infinite graphs and their properties,especially the model-checking problem, the accessibility problem and therecognised languages.We define a notion of stack trees, and a related notionof ground rewriting, which is an extension of both higher-order pushdownautomata and ground tree rewriting systems. We also define a notion ofrecognisability on the sets of ground rewriting operations through operationautomata. This notion induces a notion of recognisability over sets of stacktrees and a normalisation of recognisable sets of operations, similar to theknown notions over higher-order pushdown automata. We show that the graphsdefined by these ground stack tree rewriting systems have a decidableFO-theory, by exhibiting a finite set interpretation from a graph defined bya higher-order automaton to a graph defined by a ground stack tree rewritingsystem.We also consider the context-freeness problem for counter systems, andthe related problem of stratifiability of semi-linear sets. We prove thedecidability of the stratifiability problem for integral polyhedra and that itis coNP-complete. We use this result to show that the context-freeness problemfor flat counter systems is as well coNP-complete. Finally, we give a new proofof the decidability of the context-freeness problem for vector additionsystems, previously studied by Schwer
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Jednoduchý průmyslový Ethernet / Industrial low complexity Ethernet systemŠustek, Vladimír January 2019 (has links)
The diploma thesis is focused on the building embedded demonstration application of the proprietary Low Complexity Ethernet module for industrial usage further called the LEN/LES 2. At the first, main used technologies such as MCU, or the lightweight IP stack is discussed, Consequently, there is detailed view on system hardware architecture proposed by hardware and software requirements. Then though part describes blocks of embedded system are in term of specific parts and hardware requirements to create universal board. Following chapters expresses first startup and known hardware bugs, LWIP implementation and MODBUS system implementation. The core of the system is the new released microcontroller an ADuCM4050 and the Low Complexity Ethernet MAC-PHY prototype block and much more dependent convenient peripherals of the MCU based application.
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Návrh robotického pracoviště pro automatickou montáž extruderů pro 3D tiskárny / Design of robotic workstation for automatic assembly of extruders for 3D printersPulicar, Roman January 2019 (has links)
Thesis is dealing with the creation of robotic worplace and its periphery. The paper is discrabing the robotic function and kinematics. The practical part of the paper shows several types of suggested robotic workplaces followed by solution processing of one selected type, where technical documentation and the calculation of production is made. The end of the paper shows economical and technological evaluation of the selected type of workplace including the price returns.
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Bezdrátová síť snímačů pro měření sacího potenciálu půdy / Wireless sensors network for measurement of soil water potentialRášo, Peter January 2011 (has links)
Cílem tohoto projektu je vytvoření bezdrátové senzorické sítě na měření sacího potenciálu půdy. Práce obsahuje výběr vhodné měřící metody obsahu vody v půdě, jejíž součástí je i tvorba kalibrač˘ní křivky. Dále se zabývá realizací hardwaru a firmwaru pro dva typy modulů. Stanice end station, obsahující snímač˘e, a základní stanice base station, která přijímá a přeposílá data. Celá aplikace je doplněna o uživatelský program, který umožňuje zálohování dat, zobrazování průběhů dat včetně dat předchozích, změnu nastavení systému spolu s možností žádosti o potřebné informace.
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Analyzátor rádiových kanálů IEEE 802.15.4 / Analyzer of IEEE 802.15.4 radio channelsPokorný, Jiří January 2012 (has links)
The master’s thesis deals with development of the radio channel analyser operating in the unlicensed 2.4 GHz band according to IEEE 802.15.4 standard. The analyzer will contain two basic functions, namely energy detection of channels and analysation of selected channel. Detection of energy will be solved by selection between simple graph and text list on display. Based on information about the occupancy of channels the user can decide which channel would be set up. During the receiving of valid frame the source address, signal strength and signal quality will be stored. At the end the processor will show these data on display. For controlling the device will be installed two LEDs and four buttons.
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Statické řešení betonového komínu / Static solution of concrete chimneyKašparů, Jakub January 2013 (has links)
The goal of this Master´s thesis is a review of a reinforced concrete chimney´s stack and a foundation design based on a combination of M+N load. Two bar models (by ČSN and EN) and one shall model were created to analyze internal forces. The fine element software SCIA ENGINEERING was used to create the models. The loads taken into consideration - for analysis include self weight, lining, temperature, wind, and Karman vortex. The stack was horizontally divided by several cuts which were investigated. The stack and foundation were designed by an algorithm created in the program MS EXCEL. The piles were designed in the program GEO 5. Drawings include - drawings of shapes and drawings of the reinforcement of specifics part of chimney.
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