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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.
61

Integration Of Real-Time Experiments With Internet Access

Talakala, Pavan 01 January 2005 (has links)
The revolution of Internet – enabled instrumentation is emerging as a revolution in Measurement and Automation. New standards are being developed for transmitting data and connecting instruments to the Internet. The main purpose of this thesis is to design and develop a system to Integrate various Real – time experiments and be able to monitor and control them over Internet using LabVIEW. LabVIEW is a graphical programming package capable of data acquisition, data analysis, data presentation and real time remote control. In this thesis a Real – time system is developed which integrates several real time experiments and remote control access over Internet is provided using LabVIEW. The latest remote panel technology is used to provide the remote control access. There are four Real – time instrument experiments developed in this thesis project. They are Automatic Mixing Controller, The Digital Storage Oscilloscope from Gould Instruments, Temperature Controller and an Electronic Recording Rain/Precipitation Gauge. These four instruments are connected and communicated from the main computer by external Data Acquisition Board (DAQ) for the Automatic Mixing Controller, By General Purpose Interface Board (GPIB) for the Oscilloscope, by Data Acquisition board (DAQ) for the Temperature controller and by Serial port for the Electronic Recording Rain/Precipitation Gauge. A system is developed to integrate all the applications listed above into one application and are monitored and controlled remotely over Internet using LabVIEW.
62

Carbon Fiber Leaf Springs for Adaptive Cross Country Skiing

Atkinson, William Drew 01 June 2009 (has links) (PDF)
This work describes the development of a custom sit ski for US Ski Team paralympian Greg Mallory from concept through prototype fabrication. The ski consists of a custom seat molded specifically for the athlete, carbon fiber leaf springs, and a custom binding attachment system compatible with NNN style cross country bindings. The sit ski is designed to maximize poling power through the use of an upright rather than reclined seating position, allowing for increased utilization of core muscle strength. The springs were designed based on information gathered by a custom National Instruments data acquisition system, and stiffness analysis was conducted using Castigliano’s theorem applied to classical laminate theory.
63

Design and Implementation of DC Magnetron Sputter Deposition System and Hall Effect System Via LabView

Wright, Jason 05 February 2015 (has links)
No description available.
64

Implementation of a Hardware-in-the-Loop System Using Scale Model Hardware for Hybrid Electric Vehicle Development

Janczak, John 27 July 2007 (has links)
Hardware-in-a-loop (HIL) testing and simulation for components and control strategies can reduce both time and cost of development. HIL testing focuses on one component or control system rather than the entire vehicle. The rest of the system is simulated by computer systems which use real time data acquisition systems to read outputs and respond like the systems in the actual vehicle would respond. The hardware for the system is on a scaled-down level to save both time and money during testing. The system designed to simulate the REVLSE Equinox split parallel hybrid consists of five direct current (DC) permanent magnet motors. These motors are used in the system to test the controller software of the vehicle. Two of the motors act as power plants simulating the spark ignited Ethanol engine and the rear traction motor. These two motors are controlled by DC variable speed controllers. The other motors are used as generators to simulate the load from the belted alternator starter (BAS) and the road load on each axle. The motors on each axle are joined together mechanically using a belt and pulley system. The front and rear axle of the system are not connected to simulate the actual vehicle where the power plants are gear-reduced before they make contact with the road and therefore do not actually spin at the same speeds. The computer software and hardware used to run the HIL hybrid system is National Instruments LabView and CompactRIO. LabView provides an easy interface through which programs for the RIO can be written. The RIO gives the user the ability to measure the power into and out of different components in the system to measure the efficiency of the system. The ability to measure system efficiencies using different powertrain inputs and loading schemes is what makes the HIL system a valuable tool in control modeling for the Equinox. LabView and the RIO allow the user to optimize the control strategy with the two power plant inputs and the BAS to make sure the high voltage system stays charged and improve the overall efficiency of the vehicle without the actual vehicle. The HIL system allows other work to be done of the vehicle during the control development. During a constant axle speed test at 730 RPM with constant generator resistance, the front engine efficiency was 33.8%, the BAS efficiency was 53.0%, the rear load generator efficiency was 51.2% and the overall efficiency of the front axle was 24.0%. These results show that the system can simulate the powertrain of a hybrid vehicle and help create and validate a control scheme. / Master of Science
65

Automated spacelift training for range operators (ASTRO)

Williams, Gerald R. 01 April 2001 (has links)
No description available.
66

MBE Growth and Instrumentation

Tarigopula, Sriteja 05 1900 (has links)
This thesis mainly aims at application of principles of engineering technology in the field of molecular beam epitaxy (MBE). MBE is a versatile technique for growing epitaxial thin films of semiconductors and metals by impinging molecular beams of atoms onto a heated substrate under ultra-high vacuum (UHV) conditions. Here, a LabVIEW® (laboratory virtual instrument engineering workbench) software (National Instruments Corp., http://www.ni.com/legal/termsofuse/unitedstates/usH) program is developed that would form the basis of a real-time control system that would transform MBE into a true-production technology. Growth conditions can be monitored in real-time with the help of reflection high energy electron diffraction (RHEED) technique. The period of one RHEED oscillation corresponds exactly to the growth of one monolayer of atoms of the semiconductor material. The PCI-1409 frame grabber card supplied by National Instruments is used in conjunction with the LabVIEW software to capture the RHEED images and capture the intensity of RHEED oscillations. The intensity values are written to a text file and plotted in the form of a graph. A fast Fourier transform of these oscillations gives the growth rate of the epi-wafer being grown. All the data being captured by the LabVIEW program can be saved to file forming a growth pedigree for future use. Unattended automation can be achieved by designing a control system that monitors the growth in real-time and compares it with the data recorded from the LabVIEW program from the previous growth and adjusts the growth parameters automatically thereby growing accurate device structures.
67

Syntetiska Instrument

Borg, Daniel, Mantling, Ulf January 2009 (has links)
<p>This thesis aims to investigate SAAB AB´s possibilities to use synthetic instruments in their test systems. The reason for this is reducing costs and the risk of obsolescence which is common when test systems operate for several decades.</p><p>The market around synthetic instruments has been explored in the search for suitable hardware and software. Software has been developed in LabVIEW and synthetic instruments have been created with the help of IVI-drivers. The hardware consisted of PXI-instruments (Waveform generator and Digitizer), connected to a computer using a fiber optic link and PXI-chassi. The created instruments was then compared to common instruments used today, and the comparison turned out well. Advantages, disadvantages and the theory surrounding synthetic instruments is also covered. This thesis is only an introduction and further work will be necessary to implement synthetic instruments at SAAB.</p><p>The thesis also purposes suitable hardware and further development based on the test systems used today, and how it is possible to solve the layer structure.</p> / <p>Detta examensarbete har som mål att undersöka möjligheterna för SAAB AB att börja använda sig av syntetiska mätinstrument i sina testsystem. Anledningen till detta är att SAAB AB vill minska kostnaderna och riskerna för obsolescens som finns när testsystem är i drift i flera decennier. Detta har inneburit att marknaden har sonderats efter lämplig hårdvara och mjukvara för tillämpningen. Förutom detta har mjukvara tagits fram i LabVIEW och syntetiska instrument skapats med hjälp av IVI-drivrutiner. Som hårdvara användes PXI-instrument (vågformsgenerator och digitizer) med tillhörande chassi och fiberoptisk länk från National Instruments. De framtagna instrumenten har jämförts med vanliga reella instrument och visat sig fungera väl, men även fördelar och nackdelar belyses samt teori kring hur syntetiska instrument fungerar. Examensarbetet är endast en introduktion i ämnet och kräver ytterligare arbete innan det är praktiskt genomförbart. Förutom detta ges även förslag på lämplig hårdvara och vidareutveckling baserat på hur testsystemen ser ut i dag, och förslag på hur lageruppbyggnaden skulle kunna lösas.</p>
68

Syntetiska Instrument

Borg, Daniel, Mantling, Ulf January 2009 (has links)
This thesis aims to investigate SAAB AB´s possibilities to use synthetic instruments in their test systems. The reason for this is reducing costs and the risk of obsolescence which is common when test systems operate for several decades. The market around synthetic instruments has been explored in the search for suitable hardware and software. Software has been developed in LabVIEW and synthetic instruments have been created with the help of IVI-drivers. The hardware consisted of PXI-instruments (Waveform generator and Digitizer), connected to a computer using a fiber optic link and PXI-chassi. The created instruments was then compared to common instruments used today, and the comparison turned out well. Advantages, disadvantages and the theory surrounding synthetic instruments is also covered. This thesis is only an introduction and further work will be necessary to implement synthetic instruments at SAAB. The thesis also purposes suitable hardware and further development based on the test systems used today, and how it is possible to solve the layer structure. / Detta examensarbete har som mål att undersöka möjligheterna för SAAB AB att börja använda sig av syntetiska mätinstrument i sina testsystem. Anledningen till detta är att SAAB AB vill minska kostnaderna och riskerna för obsolescens som finns när testsystem är i drift i flera decennier. Detta har inneburit att marknaden har sonderats efter lämplig hårdvara och mjukvara för tillämpningen. Förutom detta har mjukvara tagits fram i LabVIEW och syntetiska instrument skapats med hjälp av IVI-drivrutiner. Som hårdvara användes PXI-instrument (vågformsgenerator och digitizer) med tillhörande chassi och fiberoptisk länk från National Instruments. De framtagna instrumenten har jämförts med vanliga reella instrument och visat sig fungera väl, men även fördelar och nackdelar belyses samt teori kring hur syntetiska instrument fungerar. Examensarbetet är endast en introduktion i ämnet och kräver ytterligare arbete innan det är praktiskt genomförbart. Förutom detta ges även förslag på lämplig hårdvara och vidareutveckling baserat på hur testsystemen ser ut i dag, och förslag på hur lageruppbyggnaden skulle kunna lösas.
69

Desenvolvimento de heliostato para geração heliotermica em torres solares

Silvestre, Alysson Domingos 22 April 2016 (has links)
Submitted by Márcio Maia (marciokjmaia@gmail.com) on 2016-08-08T12:09:17Z No. of bitstreams: 1 arquivototal.pdf: 3228826 bytes, checksum: ddfaa133f9f8a9a5a4d1f5233fb205a5 (MD5) / Made available in DSpace on 2016-08-08T12:09:17Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3228826 bytes, checksum: ddfaa133f9f8a9a5a4d1f5233fb205a5 (MD5) Previous issue date: 2016-04-22 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / With the increase of global perspectives regarding renewable energy and the use of concentrated solar thermal energy, with the goal of increasing the flow of solar radiation incident on the thermal has been shown to be a viable solution for electric power generation. The heliostats devices have the ability to track the Sun and reflect the radiation in a pre-set fixed point, usually known as solar tracking Tower in the middle of the field of heliostats devices. The solar towers have been aim of studies because they have a great potential for electric generation. The higher the desired concentration values of the system, the higher the accuracy requirements tracking and reflection of the heliostats, and the quality of reflective surfaces will be. This study aims to design and construction of the heliostat of two degrees of freedom for power generation in solar Tower systems using control methods for tracing and reflection on LabView platform. Applying tracking algorithms based on the solar behavior equations and mechanical design, allowing a two degrees’ freedom dynamic, it was gain results with 0.201 degrees in precision in the tracking of radiation reflection. / Com o aumento das perspectivas mundiais a respeito das energias renováveis e a utilização da energia solar térmica concentrada, com o objetivo de aumentar o fluxo de radiação solar incidente em sistemas térmicos tem se mostrado uma solução viável para geração de energia elétrica. Os dispositivos heliostatos tem a capacidade de rastrear o sol e refletir a radiação em um ponto fixo pré – estabelecido, normalmente conhecido como torre solar localizando se ao meio de um campo de dispositivos heliostatos. As torres solares tem sido alvo de estudos por possuir um grande potencial para geração de energia elétrica. Quanto maior os valores de concentração pretendido do sistema, maiores serão os requisitos de precisão de rastreamento e reflexão do heliostato e da qualidade das superfícies refletoras. Este trabalho tem como objetivo de projeto e construção de um heliostato de dois graus de liberdade para geração de energia em sistemas de torres solares utilizando métodos de controle para rastreamento e reflexão ótima em plataforma LabView. Aplicando algoritmos de rastreamento baseado nas equações de comportamento solar e projeto mecânico permitindo uma dinâmica de dois graus de liberdade foi obtido resultados de 0,201 graus de precisão no rastreamento de reflexão da radiação.
70

Sistema para medição de impedância elétrica em transdutores piezelétricos / System for measuring electrical impedance in piezoelectric transducers

Ximenes, Rodrigo Luiz, 1981- 26 August 2018 (has links)
Orientadores: Francisco José Arnold, Rangel Arthur / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-26T20:53:37Z (GMT). No. of bitstreams: 1 Ximenes_RodrigoLuiz_M.pdf: 1709801 bytes, checksum: 3d8b8086551025bf630aa238baf7d7c8 (MD5) Previous issue date: 2015 / Resumo: A medição da impedância elétrica em transdutores piezelétricos é um procedimento fundamental para a caracterização desses dispositivos. A larga variação do módulo da impedância elétrica ao longo da frequência representa uma dificuldade para a realização dessas medições. Neste trabalho é apresentado o protótipo de um medidor de impedâncias elétricas de transdutores de ultrassom utilizados em aplicações de potência elevada. O sistema opera baseado na captação dos valores de pico de tensão e corrente sob uma faixa de frequência de utilização dos transdutores. O protótipo é controlado por um microcontrolador que se comunica com um computador no qual um software, desenvolvido em LabView, armazena e mostra resultados numa interface. A validação do medidor de impedâncias foi feita pela comparação de resultados experimentais com os medidos por um analisador de impedâncias comercial. Os resultados mostram que o sistema proposto pode medir impedâncias entre 100 W e 10 kW, aproximadamente, numa faixa de frequências de até 43 kHz / Abstract: The measurement of electrical impedance of piezoelectric transducers is a fundamental procedure for the characterization of these devices. The large variation in the electrical impedance module over frequency is a difficulty to carry out these measurements. This dissertation presents the prototype of a meter electrical impedance of ultrasound transducers used in high power applications. The system operates based on the capture of peak voltage and current values of the transducers in a usage frequency band. The prototype is controlled by a microcontroller that communicates with a computer on which a software, developed in LabView, stores and displays the results in an user interface. The validation of the impedance meter was made by comparison with the experimental results measured by a commercial impedance analyzer. The results show that the proposed system can measure impedances between 10 W and 10 kW at frequencies up to 43 kHz / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia

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