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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.
251

Evaluating the use of PXI modules in tests of a radio base station

Wang, Willy January 2014 (has links)
This thesis project was carried out at the electromagnetic compatibility (EMC) department at Ericsson AB. One of the department’s goals is to seek a possible replacement to the box test instruments by utilizing PCI extension for instrumentation (PXI) modules. The main objective of this project is to evaluate how different PXI modules work during testing of a radio base station (RBS), in terms of performance, test time, and cost. A downlink decoder was implemented in LabVIEW with an extension called MathScript and several software test solutions were examined to measure error vector magnitude (EVM), frequency error, and power, and to perform parallel measurements in a multiple radio access technology (multi-RAT) test configuration. Moreover, several uplink tests were performed to decide if PXI modules are a suitable substitute for the previous box based test instruments. The findings from this study show that PXI modules can replace the previous box based test instruments. However it was concluded that not all areas can be covered and not all discrete test instrument can (yet) be replaced. Future work should complete the downlink decoder implementation in the field programmable gate array (FPGA) level in order to further improve the performance further. Future work should also examine if it is possible to replace all of the discrete test instruments with PXI modules. / Detta examensarbete utfördes på elektromagnetisk kompatibilitet (EMC) avdelningen på Ericsson AB. Ett utav avdelningens mål är att hitta en möjlig ersättare till de tidigare boxbaserade testinstrumenten genom PCI extension for instrumentation (PXI) moduler. Huvudmålet i detta projekt är att utvärdera hur olika PXI-moduler fungerar i basstationstester med hänsyn till prestanda, testtid och kostnad. En avkodare i nerlänk har implementerats i LabVIEW med hjälp av MathScript och flera mjukvarutestlösningar har undersökts för att mäta error vector magnitude (EVM), frekvensfel och effekt, samt att utföra parallella mätningar i en multipel radioteknik (multi-RAT) testkonfiguration. Dessutom har flera upplänkstester utförts för att avgöra om PXI-moduler är en lämplig ersättare till de tidigare boxbaserade testinstrumenten. Resultaten från denna studie visar att PXI-moduler kan ersätta tidigare boxbaserade testinstrumenten, men dessa resultat visar även att inte alla områden kan täckas och inte alla diskreta testinstrument kan ersättas (ännu). Framtida arbete ska slutföra implementationen av avkodare i nerlänk i fältprogrammerbar grindmatris (FPGA)-nivå för att förbättra prestandan ytterligare. Framtida arbete bör även undersöka om det är möjligt att ersätta alla diskreta testinstrument med PXI-moduler.
252

Автоматизация процессов синтеза слоистых структур и исследование их электрофизических характеристик : магистерская диссертация / Automation of synthetic processes of layered structures and investigation of their electrophysical characteristics

Грязнов, А. О., Gryaznov, A. O. January 2017 (has links)
С помощью оборудования National Instruments реализованы две установки для нанесения органических покрытий. Установка термовакуумного нанесения с виртуальным прибором «ThermoVac» позволяет производить линейный нагрев испаряемого вещества с фиксированной скоростью до заданной температуры термостатирования в диапазоне от комнатной до 500 °C. Установка для нанесения методом центрифугирования с ВП «SC_organic» позволяет поддерживать заданную скорость вращения подложки в диапазоне от 500 до 9000 об/мин. На базе микрозондовой станции Cascade Microtech MPS150 разработан автоматизированный канал для тестирования мемристорных структур, в режиме многократного чтения и записи. ВП «RW MIM» формирует на выходе SMU источника последовательность импульсов заданной амплитуды и длительности в режимах запись/чтение. Выполнено нанесение и аттестация пленок 5,11-диметил-5,11-дигидроиндоло [3.2-b]карбазола и 5,11-дигексил-5,11-дигидроиндоло[3.2-b]карбазола. По измеренным вольтамперным характеристикам получено, что полупроводник в синтезированных структурах TiN/DMICZ/Au, Ti/DMICZ/Au обладает дырочной проводимостью с подвижностью μ = 4.9∙10-7 см2/(В∙с). Показано, что регистрируемая ВАХ характеризуется петлями гистерезиса, которые свидетельствуют о наличии мемристивного эффекта в образцах TiN/DHICZ/Au. Произведено тестирование исследуемых слоистых структур в режимах многократного чтения/записи. / An automated installation based on National Instruments equipment, two installations for applying organic coatings are implemented. The installation of a thermo vacuum evaporation with a virtual device "ThermoVac" allows linear heating of the evaporated substance at a fixed rate of up to 500 ° C. The centrifugal centrifugation unit with an VI “SC_organic” supports the specified rotation speed of the substrate in the range of 500 to 9000 rpm. Based on the microprobe station Cascade Microtech MPS150, an automated channel was developed for testing memristor structures, in the mode of multiple reading and writing. VI "RW MIM" forms a sequence of pulses of the specified amplitude and duration in the write / read modes at the SMU output of the source. The deposition and validation of 5,11-dimethyl-5,11-dihydroindolo [3.2-b] carbazole and 5,11-dihexyl-5,11-dihydroindolo [3.2-b] carbazole films was performed. From the measured volt-ampere characteristics, it was found that the semiconductor in the synthesized TiN / DMICZ / Au, Ti / DMICZ / Au structures has a hole conductivity with a mobility μ = 4.9 ∙ 10-7 cm2/(V∙s). It is shown that the recorded I-V characteristic is characterized by hysteresis loops that indicate the presence of a memorial effect in TiN / DHICZ / Au samples. The testing of layered structures under test in multiple read / write modes was performed.
253

Balkböjning och signalbehandling / Beam bending and signal processing

Forsling Ekblom, Albin, Ohlén, Rickard January 2021 (has links)
I laborationssalarna på KTH i Södertälje, som i huvudsak används till elektrorelaterade ämnen, har det funnits ett antal balkmodeller med monterade töjningsgivare. Dessa har inte använts på många år och det saknas vidare uppgifter om modellerna. Uppdraget bestod av att utarbeta en laboration till KTH:s undervisning. Laborationen skulle handla om balkböjning och signalbehandling, med tonvikt på̊ det senare. Som hjälpmedel skulle vi använda oss av balkmodellerna. I uppdraget ingick det också att undersöka balkmodellernas elektriska och mekaniska egenskaper. Med teknisk balkteori skulle en möjlig relation mellan nedböjning och töjning tas fram. Med balkmodellen i en bryggkoppling kunde dess signal via ett DAQ-kort överföras till en PC och LabVIEW för vidare behandling. I LabVIEW kan ett anpassat gränssnitt tas fram och för visning av valda parametrar. Bryggkopplingen balanseras med hjälp av en potentiometer. I gränssnittet kan spänningsförändringen i bryggan observeras när balken påverkas av nedböjning. Efter kalibrering av systemet kan töjning och nedböjning presenteras efter beräkningar i LabVIEW. För att erhålla en så stabil och brusfri signal som möjligt har gruppen använt sig avbåde ett hårdvarufilter av lågpass-typ och ett mjukvarufilter i LabVIEW. Signalen förstärks med hjälp av en OP-förstärkare innan den matas in i DAQ-kortet. Trots sin ålder kunde balkmodellerna fortfarande användas och ge stabila signaler för vidarebehandling. Modellerna kan med fördel användas i en laboration för studenter och färdigt underlag finns för detta. Laborationen bör öka förståelsen för hur en signal från en givare kan förstärkas, filtreras och behandlas vidare i detta fall för grundläggande hållfasthetsberäkningar. / In the laboratory at KTH in Södertälje, which are mainly used for electro-related subjects, there are a number of beam models with mounted strain gauges. These have not been used for many years and there is no further information about the models. The assignment consisted of preparing a laboratory task for KTH's teaching. The laboratory would consist of beam bending and signal processing, with emphasis on the latter. As an aid, the beam models will be used, these consisted of a fixed aluminum beam with mounted strain gauges. The assignment also includes examining the electrical and mechanical properties of the beam models. With technical beam theory, a possible relationship between deflection and strain would be developed. With the beam model connected in a bridge connection, its signal could be transferred via a DAQ card to a PC and LabVIEW for further processing. In LabVIEW, a custom interface can be created and for displaying selected parameters. The bridge coupling is balanced with the help of a potentiometer. In the interface, the voltage change in the bridge can be observed when the beam is affected by deflection. After calibration of the system in the interface, strain and deflection can be presented according to calculations in LabVIEW. To obtain as stable and noise-free a signal as possible, the group has used both a low-pass hardware filter and a LabVIEW software filter. The signal is amplified by an OP amplifier before being fed into the DAQ card. Despite their age, the beam models could still be used and give stable signals for further treatment. The models can be used to advantage in a laboratory for students and there is a ready basis for this. The laboratory should increase the understanding of how a signal from a sensor can be amplified, filtered and further processed in this case for basic strength calculations.
254

AUTOMATED SOLID-SUBSTRATE CULTIVATION OF THE ANAEROBIC BACTERIUM CLOSTRIDIUM THERMOCELLUM

Ruwaya, Mathew J. 01 January 2016 (has links)
The organism Clostridium thermocellum grows on cellulosic substrates and produces ethanol, acetate, lactate, formic acid, and CO2. The organic acids produced alter the growth environment in which the bacteria grows and ultimately inhibit bacterial growth. One method which has been used successfully to maintain the system at acceptable growth conditions is to intermittently flush out the spent media and metabolic products and replace with new fermentation media. Our goal was to design and build an automated system that will automatically flush the spent media from the growing culture and resupply new media without manual intervention. An automated control system was designed and built to control growth parameters. Heated water was pumped through the jacket of each culture vessel and used to regulate the reactor temperature. Sensors for pH and temperature were connected to a central data acquisition system and NI LabVIEW software was used to control each of the components through the signals provided by the data acquisition system. Peristaltic and vacuum pumps were used to supply growth media and acquire reproducible samples for HPLC analysis with limited contamination. In a series of trials, targeted temperature and moisture conditions were achieved and new media was passed through each reactor using a time trigger. More product was produced in manual and automatically flushed cultures than in batch.
255

DESIGN OF A RACE CAR TELEMETERING SYSTEM

Ameri, K. Al, Hanson, P., Newell, N., Welker, J., Yu, K, Zain, A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This student paper was produced as part of the team design competition in the University of Arizona course ECE 485, Radiowaves and Telemetry. It describes the design of a telemetering system for race cars. Auto Racing is an exciting sport where the winners are the ones able to optimize the balance between the driver’s skill and the racing teams technology. One of the main reasons for this excitement is that the main component, the race car, is traveling at extremely high speeds and constantly making quick maneuvers. To be able to do this continually, the car itself must be constantly monitored and possibly adjusted to insure proper maintenance and prevent damage. To allow for better monitoring of the car’s performance by the pit crew and other team members, a telemetering system has been designed, which facilitates the constant monitoring and evaluation of various aspects of the car. This telemetering system will provide a way for the speed, engine RPM, engine and engine compartment temperature, oil pressure, tire pressure, fuel level, and tire wear of the car to be measured, transmitted back to the pit, and presented in a way which it can be evaluated and utilized to increase the car’s performance and better its chances of winning the race. Furthermore, this system allows for the storing of the data for later reference and analysis.
256

Optical sorting and manipulation of microscopic particles

Milne, Graham January 2007 (has links)
Over the last few decades, the use of light to control and manipulate microscopic particles has become widespread. These methods are enabling new areas of research to flourish across the physical and biological sciences. This thesis describes investigations into both optical trapping and the closely related field of optical sorting. It documents the development of a variety of new techniques. The thesis begins with a short review of optical trapping and existing methods for sorting mixtures of microscopic particles. The first half of this chapter highlights some of the reasons behind optical trapping's rapid growth in popularity. By reviewing an array of methods for sorting particles and discussing the relative merits of each, the case for optical sorting is established. The second chapter describes research into using a spatial light modulator to create three-dimensional optically trapped colloidal structures using the time-sharing technique. Limiting factors inherent in the technology are discussed in detail. The third chapter reviews a sophisticated particle-tracking software package that has proved to be a considerable success. It was developed explicitly with colloidal microscopy in mind and experimental plots produced by the software are used throughout the thesis. Experimental studies have been performed into the behaviour of microscopic particles moving under the influence of two classes of propagation-invariant beams: Mathieu beams and Bessel beams. The Bessel beam studies have been complimented by a theoretical model and have led ultimately to a new method for the static optical sorting of both solid particles and biological cells, with particular emphasis on human blood. The fifth and final chapter describes how re-configurable optical devices can be implemented to spatially separate different colloidal species. A new method for creating arbitrary optical landscapes using an acousto-optic modulator is reported. This new technique is then used to optically sort four particle species simultaneously - the first experimental demonstration of polydisperse optical fractionation. Additionally, experiments are reported that demonstrate controlled, static optical sorting using a spatial light modulator.
257

Novel Apparatus to Control Electrospinning Fiber Orientation for the Production of Tissue Engineering Scaffolds

Boland, Eugene David 01 January 2004 (has links)
The conception of electrospinning can trace its roots back more than 400 years, when it was observed that rubbed amber can deform a droplet of water on a smooth surface, and is based upon simple concepts of charge separation and surface tension. Since that time, considerable effort has been directed at both the cause and utility of this phenomenon. The specific aim of this dissertation project was to develop an automated electrostatic processing apparatus that was capable of controlling the three-dimensional architecture of an electrospun scaffold to further improve its utility in tissue engineering. The efficacy of using this technique has been well documented and can be adapted to produce tissue engineering scaffolds for a variety of tissues and organs. This apparatus incorporates precise mandrel motion. The system is capable of 0 - 5000 revolution per minute rotation, 0 - 25 inch per second translation and ± 40° rotation about the electrospinning jet axis for repeatable scaffold production. Fiber alignment and scaffold density are precisely controlled by rotating a mandrel along one axis, translation along that same axis, and rotation around the second axis perpendicular to the electrospun fiber stream. The control is accomplished with a PC based "supervisory" control program written partially in the LabVIEW® programming language and partially in SI Programmer supplied by Applied Motion Products. Scaffold thickness and fiber diameters are determined by the syringe metering pump flow rate, material being electrospun and solution concentrations. Through extensive laboratory analysis (mechanical testing and both optical and electron microscopy), parameters such as fiber orientation, diameter and mechanics can be predictive from specific polymer setups. Our laboratory has demonstrated the ability to electrospin natural and synthetic polymers and this apparatus will be utilized to tailor scaffolds to meet specific tissue engineering needs by creating a truly biomimicking scaffold / extracellular matrix.
258

Instrumentação virtual aplicada ao ensino experimental de engenharia elétrica. / Virtual instrumentation applied to electrical engineering education.

Lopes, Vinícius José Santos 20 September 2007 (has links)
A proposta deste trabalho é apresentar algumas potenciais aplicações do software LabVIEW da National Instruments, associado a um hardware de aquisição de dados, aplicado em experiências ligadas à área de sistemas de energia elétrica como ferramenta de apoio ao ensino presencial. Esta dissertação mostra o desenvolvimento de uma experiência em um laboratório de sistemas de energia elétrica que utilizam sensores Hall de tensão e corrente, uma placa A/ D e o software LabVIEW para monitorar variáveis elétricas, calcular e analisar potência, energia e fator de potência de um minissistema de energia em baixa tensão, que contém geradores síncronos trifásicos de 2kVA-220 V, um modelo de uma linha de transmissão com reatores e capacitores, e uma caixa de resistência para representar uma carga passiva. Uma placa A/ D permite saídas digitais, que por sua vez podem controlar contatores que ligam ou desligam elementos do circuito em análise. Um programa foi desenvolvido para servir como ferramenta de apoio no processo ensino-aprendizagem. Este programa possibilita monitorar e atuar na montagem experimental, disponibilizando três instrumentos virtuais básicos para o desenvolvimento da experiência. Estes três instrumentos são: uma primeira tela que mostra o diagrama dos fasores de todos os sinais de tensão e corrente simultaneamente; uma segunda tela, que mostra a forma de onda dos sinais de tensão e corrente no minissistema com as suas respectivas defasagens; e a terceira e última tela que fornece um sincronoscópio virtual possibilitando analisar os ajustes de tensão e freqüência necessários na operação de paralelismo do minissistema com a concessionária de energia. Este programa possibilita o acesso à montagem experimental do minissistema de energia pelo computador instalado na bancada do laboratório, permitindo também aos alunos, o monitoramento e controle do experimento a partir de seus próprios computadores, visualizando e reforçando no laboratório, os conceitos vistos na teoria. / The proposal of this work is to present some potential applications of the software LabVIEW, from National Instruments, associated with data acquisition hardware, applied to experiments in the Electric Energy Systems area as a tool to support the presential education. This dissertation shows the developing of an experience in a electric energy system laboratory, which use Hall Effect sensors, A/D data acquisition board, connected to a PC, and the software LabVIEW (National Instruments) in order to monitor electrical parameters, calculate and analyze power, energy and power factor in a low-voltage power system, which contains synchronous three-phase generators of 2 kVA-220V, with a transmission line model provided with reactors and capacitors, and a resistance box representing a passive load. The A/D board allows controlling digital outputs that can control counters that switch on or off the circuit elements in the analysis. A program was developed in order to act a tool to support the process teaching-learning. This program allows to monitor and to act in the experimental assembly providing three basic virtual tools for the experiment development. These three tools are: one screen that simultaneously shows the phasor diagram with current and voltage; a second screen that shows voltage and current waveform of the mini-system with its respective imbalances; and the third and last screen, that provides a virtual synchronoscope which makes possible the analysis of the necessary adjustments of voltage and frequency in the operation of parallelism between the mini-system and the energy power supplier. This program allows the access to the experimental assembly of the energy mini-system through a computer installed in a bench of the laboratory. As a result, the students can also monitor and control the experiments through their own computers, allowing them to visualize and to reinforce in the laboratory, the concepts taught in theory.
259

Application of LabVIEW and myRIO to voice controlled home automation

Lindstål, Tim, Marklund, Daniel January 2019 (has links)
The aim of this project is to use NI myRIO and LabVIEW for voice controlled home automation. The NI myRIO is an embedded device which has a Xilinx FPGA and a dual-core ARM Cortex-A9processor as well as analog input/output and digital input/output, and is programmed with theLabVIEW, a graphical programming language. The voice control is implemented in two differentsystems. The first system is based on an Amazon Echo Dot for voice recognition, which is acommercial smart speaker developed by Amazon Lab126. The Echo Dot devices are connectedvia the Internet to the voice-controlled intelligent personal assistant service known as Alexa(developed by Amazon), which is capable of voice interaction, music playback, and controllingsmart devices for home automation. This system in the present thesis project is more focusingon myRIO used for the wireless control of smart home devices, where smart lamps, sensors,speakers and a LCD-display was implemented. The other system is more focusing on myRIO for speech recognition and was built on myRIOwith a microphone connected. The speech recognition was implemented using mel frequencycepstral coefficients and dynamic time warping. A few commands could be recognized, includinga wake word ”Bosse” as well as other four commands for controlling the colors of a smart lamp. The thesis project is shown to be successful, having demonstrated that the implementation ofhome automation using the NI myRIO with two voice-controlled systems can correctly controlhome devices such as smart lamps, sensors, speakers and a LCD-display.
260

Automatizovaný systém pro měření teplotních zkoušek senzorů / Measuring system for temperature test of sensors

Turanský, Luboš January 2012 (has links)
In this work is described design of measuring and evaluation system for temperature rise tests in cooperation with ABB company. As temperature sensors are used thermocouples type L and measuring hardware consists of chassis cRIO 9073 and measuring card NI 9213. In LabVIEW 2011 is created software for cRIO and as well for control PC and structure of both programs is described in detail. Thesis includes also practical estimation of metrological parameters of created system.

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