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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.
121

Návrh měřicího pracoviště v LabView pro účely měření spektra a světelného toku / Design of measuring workspace in LabView for purpose of spectrum and luminous flux measurement

Sláma, Pavel January 2017 (has links)
This thesis deals with luminance parameters measurement and ways to accomplish this using LabView software. The first part focuses on luminance parameters measurable by spectroradiometer and their meaning. Following part introduces reader to hardware equipment that is used in the measurement. Third part contains description of LabView software and explains what is required to make a communication between equipment and PC work. Next part explains how the communication with peripherals was achieved. Following up is the part where it is described how programs controlling AC and DC power supplies work. In this part the user interface is described.
122

Sistema de processamento de sinais e geração de imagens químicas para sensores LAPS, FMOS e TAOS baseado em dispositivos lógicos programáveis FPGA. / Signal processing system and generation of chemical imaging to LAPS, FMOS and TAOS sensors based on FPGA programmable logic devices.

Santos, Daniela de Souza 18 March 2014 (has links)
Os crescentes problemas relacionados à poluição do meio ambiente colocam desafios para o desenvolvimento de sistemas de sensores integrados e portáteis que permitam o monitoramento do ambiente em tempo real. Nesse sentido, no presente trabalho foi projetado e implementado um sistema de aquisição, processamento de sinais e geração de imagens químicas aplicado para a medição do nível de pH e detecção de metais pesados e elementos patogênicos totalmente integrado e construído na placa sbRIO-9631. O sistema foi desenvolvido e integrado um amplificador Lock-in digital para leitura de valores de mudança de fase e intensidade dos sinais provenientes de sensores optoeletrônicos LAPS, TAOS e FMOS. Foi também desenvolvido e integrado a um sistema automatizado de controle de mistura de gases para realizar ensaios de calibração do sensor e medições de tempo de resposta dos sensores. Também foi integrado um sistema automatizado de escaneamento XY de fonte de luz de excitação para os sensores ópticos utilizando um display OLED-128-G1. Este sistema ainda pode ser integrado a dispositivos móveis via Internet para transferência de dados a centros de pesquisa e monitoramento. O sistema integrado com todas as unidades acima descritas mostrou ser um sistema portátil, reconfigurável e eficiente para a aquisição e processamento de sinais de resposta de diversos tipos de sensores tais com LAPS, TAOS e FMOS. / The problems of environment pollution increasingly growing and pose challenges for the development of integrated and portable sensor systems that allow the monitoring of the environment in real time. In that sense in the present work was designed and implemented an acquisition system, signal processing and chemical Imaging generation to apply in the pH level measurement and the detection of heavy metals and pathogenic elements fully integrated and built on the sbRIO-9631 board. In the system was developed and integrated a digital Lock-in amplifier for reading values of phase shift and intensity of the signals coming from optoelectronic sensors LAPS, TAOS and FMOS. It was also developed and integrated on the sbRIO-9636 an automated gas mixture control system to perform tests for calibration of the sensor and measure the sensor response time. It was developed and integrated an automated XY scan system for light source to excited optical sensors using a OLED-128-G1 display. This system can be integrated into mobile devices via Internet for transferring data to research and monitoring centers. The integrated system with all the units described above proved to be a portable, reconfigurable and efficient system for data acquisition and signal processing from many types of sensors such as LAPS, TAOS and FMOS.
123

Muspel and Surtr : CVD system and control program for WF6 chemistry

Gerdin Hulkko, Johan January 2019 (has links)
CVD (Chemical Vapour Deposition) is an advanced technique for depositing a coating on a substrate. CVD implies that a solid phase is deposited on a normally heated substrate surface using a reactive, gaseous mixture. The reaction gas mixture must be carefully chosen to prevent homogeneous nucleation in the gas phase. As the solid phase is formed, gaseous by-products are formed and they must be removed from the CVD system. The thermally activated CVD process requires a deposition system which can regulate the total pressure and mass flows of the separate gas components as well as maintain a sufficiently high temperature to initiate a chemical reaction on the substrate surface. In this thesis a new CVD system was constructed to meet these challenges. Initially it will be used to deposit hard, wear resistant coatings but by changing the gases, it is possible to explore other chemical systems. The CVD system functions well up to a deposition temperature of 1100 ºC as long as the CVD processes are thermally activated. Apart from manual operation, a LabView control interface was implemented that can automate process steps by reading recipe files as csv (comma-separated variables). In this way complex coating architectures can be deposited. The aim of this thesis is to give a detailed description of the hardware set-up and of the software developed for it. Provided in this work are also a few examples of W and WN (tungsten nitride) coatings, including a multi-layered structure to show the potential of complex structures. Since the system also contains a titanium precursor, a TiN (titanium nitride) coating is presented to conceptually show the flexibility of the equipment. / CVD är en avancerad teknik för att lägga en tunn film runt ett substrat. CVD innebär att en fast fas bildas på den normalt uppvärmda substratytan från en reaktiv gasblandning. Gasblandningen är väl vald att inte förorsaka homogen kärnbildning i gasfasen. När den fasta fasen bildas så bildas också gasformiga biprodukter som måste pumpas ut ur systemet. Den termiskt aktiverade CVD processen kräver ett system som kan styra total trycket och massflödet av de individuella gaskomponenterna samt hålla en tillräcklig temperatur för att initiera kemiska reaktioner på substratytan. I denna avhandling presenteras ett CVD-system byggt för att möta dessa utmaningar. Initialt kommer systemet att deponera hårda, slittåliga skikt men genom gasbyte byte av gas kan andra materialsystem utforskas. CVD-systemet kan deponera andra typer av filmer upp till en deponeringstemperatur på 1100°C så länge som CVD-processerna är termiskt aktiverade. Utöver manuell styrning har ett styrprogram i LabView implementerats för att medge automatisering av processtegen genom att läsa av receptfiler i csv-format. På det här sättet kan mer komplicerade skiktarkitekturer deponeras. Målet med detta arbete är att ge en detaljerad beskrivning av uppställningen samt mjukvaran som framställts. Ett antal exempel på W- (volfram) och WN-skikt (volframnitrid) presenteras tillsammans med en multiskiktslösning för att visa potentialen för komplicerade strukturer. Eftersom systemet även har tillgång till en titankälla presenteras ett TiN-skikt (titannitrid) för att konceptuellt demonstrera utrustningens flexibilitet.
124

Sistema de processamento de sinais e geração de imagens químicas para sensores LAPS, FMOS e TAOS baseado em dispositivos lógicos programáveis FPGA. / Signal processing system and generation of chemical imaging to LAPS, FMOS and TAOS sensors based on FPGA programmable logic devices.

Daniela de Souza Santos 18 March 2014 (has links)
Os crescentes problemas relacionados à poluição do meio ambiente colocam desafios para o desenvolvimento de sistemas de sensores integrados e portáteis que permitam o monitoramento do ambiente em tempo real. Nesse sentido, no presente trabalho foi projetado e implementado um sistema de aquisição, processamento de sinais e geração de imagens químicas aplicado para a medição do nível de pH e detecção de metais pesados e elementos patogênicos totalmente integrado e construído na placa sbRIO-9631. O sistema foi desenvolvido e integrado um amplificador Lock-in digital para leitura de valores de mudança de fase e intensidade dos sinais provenientes de sensores optoeletrônicos LAPS, TAOS e FMOS. Foi também desenvolvido e integrado a um sistema automatizado de controle de mistura de gases para realizar ensaios de calibração do sensor e medições de tempo de resposta dos sensores. Também foi integrado um sistema automatizado de escaneamento XY de fonte de luz de excitação para os sensores ópticos utilizando um display OLED-128-G1. Este sistema ainda pode ser integrado a dispositivos móveis via Internet para transferência de dados a centros de pesquisa e monitoramento. O sistema integrado com todas as unidades acima descritas mostrou ser um sistema portátil, reconfigurável e eficiente para a aquisição e processamento de sinais de resposta de diversos tipos de sensores tais com LAPS, TAOS e FMOS. / The problems of environment pollution increasingly growing and pose challenges for the development of integrated and portable sensor systems that allow the monitoring of the environment in real time. In that sense in the present work was designed and implemented an acquisition system, signal processing and chemical Imaging generation to apply in the pH level measurement and the detection of heavy metals and pathogenic elements fully integrated and built on the sbRIO-9631 board. In the system was developed and integrated a digital Lock-in amplifier for reading values of phase shift and intensity of the signals coming from optoelectronic sensors LAPS, TAOS and FMOS. It was also developed and integrated on the sbRIO-9636 an automated gas mixture control system to perform tests for calibration of the sensor and measure the sensor response time. It was developed and integrated an automated XY scan system for light source to excited optical sensors using a OLED-128-G1 display. This system can be integrated into mobile devices via Internet for transferring data to research and monitoring centers. The integrated system with all the units described above proved to be a portable, reconfigurable and efficient system for data acquisition and signal processing from many types of sensors such as LAPS, TAOS and FMOS.
125

Sistemas computacionais de apoio à monitoração de estruturas de engenharia civil. / Computational systems to support monitoring of civil engineering structures.

Assis, Wayne Santos de 24 May 2007 (has links)
Este trabalho apresenta o desenvolvimento de sistemas computacionais de apoio à aquisição, visualização e tratamento de dados provenientes de monitoração de estruturas de Engenharia Civil. Por meio dos sistemas construídos, torna-se possível adquirir, visualizar e filtrar informações com facilidade, ao mesmo tempo em que se permite avaliar a influência da temperatura, da retração e da fluência nos elementos estruturais monitorados. Buscando desenvolver as ferramentas computacionais em uma perspectiva alinhada com necessidades reais do setor, foram monitoradas duas pontes rodoviárias e uma estação metroviária, sendo utilizada instrumentação avançada baseada em sensores e equipamentos ópticos e elétricos, permitindo a medição de grandezas como deformação, temperatura, deslocamento e rotações. A experiência adquirida em campo encontra-se descrita, apresentando-se a estrutura e componentes dos modernos sistemas de monitoração e os principais resultados decorrentes da sua aplicação nas obras monitoradas. Nesse contexto, os sistemas computacionais construídos demonstraram ser úteis ferramentas, auxiliando nas diversas fases da monitoração estrutural, desde a aquisição até a interpretação dos resultados. / This work presents the development of computational systems to support acquisition, visualization, and treatment of data from health monitoring systems of civil structures. With these systems, it is possible to acquire, to visualize, and to filter monitored data. It is also possible to evaluate the influence of temperature, shrinkage and creep in structural elements. The goal is the development of tools to fulfill real needs. For that, two bridges and a subway station were monitored using advanced instrumentation based on optical and electrical sensors. The acquired experience in field is described, presenting the structure and the various components of modern structural health monitoring systems, as well as the main results of application in the monitored structures. In that context, the built computational systems demonstrated to be very useful, aiding in the several phases of the structural monitoring from the acquisition to the interpretation of the results.
126

Styrning av stegmotor för robot med NICompactRIO

Augustsson, Joacim, Larsson, Gustaf January 2009 (has links)
Arbetet handlar om styrning och reglering av stegmotorer och permanentmagnetmotorer, genom attanvända det grafiska programmeringsspråket Labview från National Instruments (NI) tillsammansmed hårdvara i form av NI CompactRIO och NI USB datainsamlingskort. Implementeringen har sketti form av en robot med ett för uppgiften specialbyggt styrsystem, PWM – styrning av enpermanentmagnetmotor och en egenkonstruerad manöverdosa. / This report deals about controlling and regulating stepping motors and PM-motors by using thegraphical programming language NI Labview, with hardware NI CompactRIO and NI DAQ-USB.The implementation has been done by controlling a robot with a for the task built system, controllinga PM-motor by PWM and a own created controller.
127

Verification techniques in the context of event-trigged soft real-time systems / Verifikationstekniker för event-triggade mjuka realtidssystem

Norberg, Johan January 2007 (has links)
<p>When exploring a verification approach for Komatsu Forest's control system regarding their forest machines (Valmet), the context of soft real-time systems is illuminated. Because of the nature of such context, the verification process is based on empirical corroboration of requirements fulfillment rather than being a formal proving process.</p><p>After analysis of the literature with respect to the software testing field, two paradigms have been defined in order to highlight important concepts for soft real-time systems. The paradigms are based on an abstract stimuli/response model, which conceptualize a system with inputs and output. Since the system is perceived as a black box, its internal details are hidden and thus focus is placed on a more abstract level.</p><p>The first paradigm, the “input data paradigm”, is concerned about what data to input to the system. The second paradigm, the “input data mechanism paradigm” is concerned about how the data is sent, i.e. the actual input mechanism is focused. By specifying different dimensions associated with each paradigm, it is possible to define their unique characteristics. The advantage of this kind of theoretical construction is that each paradigm creates an unique sub-field with its own problems and techniques.</p><p>The problems defined for this thesis is primarily focused on the input data mechanism paradigm, where devised dimensions are applied. New verification techniques are deduced and analyzed based on general software testing principles. Based on the constructed theory, a test system architecture for the control system is developed. Finally, an implementation is constructed based on the architecture and a practical scenario. Its automation capability is then assessed.</p><p>The practical context for the thesis is a new simulator under development. It is based upon LabVIEW and PXI technology and handles over 200 I/O. Real machine components are connected to the environment, together with artificial components that simulate the engine, hydraulic systems and a forest. Additionally, physical control sticks and buttons are connected to the simulator to enable user testing of the machine being simulated.</p><p>The results associated with the thesis is first of all that usable verification techniques were deduced. Generally speaking, some of these techniques are scalable and are possible to apply for an entire system, while other techniques may be appropriate for selected subsets that needs extra attention. Secondly, an architecture for an automated test system based on a selection of techniques has been constructed for the control system.</p><p>Last but not least, as a result of this, an implementation of a general test system has been possible and successful. The implemented test system is based on both C# and LabVIEW. What remains regarding the implementation is primarily to extend the system to include the full scope of features described in the architecture and to enable result analysis.</p> / <p>Då verifikationstekniker för Komatu Forests styrsystem utreds angående Valmet skogsmaskiner, hamnar det mjuka realtidssystemkontextet i fokus. Ett sådant kontext antyder en process där empirisk styrkning av kravuppfyllande står i centrum framför formella bevisföringsprocesser.</p><p>Efter en genomgång och analys av litteratur för mjukvarutestområdet har två paradigmer definierats med avsikten att belysa viktiga concept för mjuka realtidssystem. Paradigmerna är baserade på en abstrakt stimuli/responsmodell, som beskriver ett system med in- och utdata. Eftersom detta system betraktas som en svart låda är inre detaljer gömda, vilket medför att fokus hamnar på ett mer abstrakt plan.</p><p>Det första paradigmet benämns som “indata-paradigmet” och inriktar sig på vilket data som skickas in i systemet. Det andra paradigmet går under namnet “indatamekanism-paradigmet” och behandlar hur datat skickas in i systemet, dvs fokus placeras på själva inskickarmekanismen. Genom att definiera olika</p><p>dimensioner för de två paradigmen, är det möjligt att beskriva deras utmärkande drag. Fördelen med att använda denna teoretiska konstruktion är att ett paradigm skapar ett eget teoriområde med sina egna frågeställningar och tekniker.</p><p>De problem som definierats för detta arbete är främst fokuserade på indatamekanism-paradigmet, där framtagna dimensioner tillämpas. Nya verifikationstekniker deduceras och analyseras baserat på generella mjukvarutestprinciper. Utifrån den skapade teorin skapas en testsystemarkitektur för kontrollsystemet. Sedan utvecklas ett testsystem baserat på arkitekturen samt ett praktiskt scenario med syftet att utreda systemets automationsgrad.</p><p>Den praktiska miljön för detta arbete kretsar kring en ny simulator under utveckling. Den är baserad på LabVIEW och PXI-teknik och hanterar över 200 I/O. Verkliga maskinkomponenter ansluts till denna miljö tillsammans med konstgjorda komponenter som simulerar motorn, hydralik samt en skog. Utöver detta, ansluts styrspakar och knappar för att möjliggöra användarstyrning av maskinen som simuleras.</p><p>Resultatet förknippat med detta arbete är för det första användbara verifikationstekniker. Man kan generellt säga att några av dessa tekniker är skalbara och därmed möjliga att tillämpa för ett helt system. Andra tekniker är ej skalbara, men lämpliga att applicera på en systemdelmängd som behöver testas mer utförligt.</p><p>För det andra, en arkitektur har konstruerats för kontrollsystemet baserat på ett urval av tekniker. Sist men inte minst, som en följd av ovanstående har en lyckad implementation av ett generellt testsystem utförts. Detta system implementerades med hjälp av C# och LabVIEW. Det som återstår beträffande implementationen är att utöka systemet så att alla funktioner som arkitekturen beskriver är inkluderade samt att införa resultatanalys.</p>
128

Styrning av stegmotor för robot med NICompactRIO

Augustsson, Joacim, Larsson, Gustaf January 2009 (has links)
<p>Arbetet handlar om styrning och reglering av stegmotorer och permanentmagnetmotorer, genom attanvända det grafiska programmeringsspråket Labview från National Instruments (NI) tillsammansmed hårdvara i form av NI CompactRIO och NI USB datainsamlingskort. Implementeringen har sketti form av en robot med ett för uppgiften specialbyggt styrsystem, PWM – styrning av enpermanentmagnetmotor och en egenkonstruerad manöverdosa.</p> / <p>This report deals about controlling and regulating stepping motors and PM-motors by using thegraphical programming language NI Labview, with hardware NI CompactRIO and NI DAQ-USB.The implementation has been done by controlling a robot with a for the task built system, controllinga PM-motor by PWM and a own created controller.</p>
129

Controle térmico de alta exatidão e sua aplicação na determinação de propriedades térmicas de materiais

Nascimento, Leonaldo José Lyra do 14 December 2012 (has links)
Made available in DSpace on 2015-05-08T14:59:50Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5685009 bytes, checksum: 7c7cec127c61d91393979e6be4ef4ab5 (MD5) Previous issue date: 2012-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper presents a theoretical and experimental study of a PID control-Proportional, Integral and Derivative using PELTIER module that achieves precision of about 0.01oC. It is developed to study the integrated instrumentation and control heat transfer. Based on this we developed a heat signal generator on a flat surface and applied to the measurement of thermal properties, in a system similar to electrical circuit. After several experiments, the results indicates the validity of the proposal. / Neste trabalho apresenta-se um estudo teórico e experimental de um controle P.I.D.- Proporcional, Integral e Derivativo, utilizando módulos Peltier s que alcançam precisão de cerca de 0.01oC. É desenvolvido o estudo da instrumentação e controle integrado à transferência de calor. Baseado neste controle foi desenvolvido um gerador de sinais térmicos em uma superfície plana e aplicado na medida de propriedades térmicas, em um sistema semelhante ao circuito elétrico. Após vários ensaios experimentais usando amostras sólidas, os resultados indicam a validade da proposta.
130

Sistemas computacionais de apoio à monitoração de estruturas de engenharia civil. / Computational systems to support monitoring of civil engineering structures.

Wayne Santos de Assis 24 May 2007 (has links)
Este trabalho apresenta o desenvolvimento de sistemas computacionais de apoio à aquisição, visualização e tratamento de dados provenientes de monitoração de estruturas de Engenharia Civil. Por meio dos sistemas construídos, torna-se possível adquirir, visualizar e filtrar informações com facilidade, ao mesmo tempo em que se permite avaliar a influência da temperatura, da retração e da fluência nos elementos estruturais monitorados. Buscando desenvolver as ferramentas computacionais em uma perspectiva alinhada com necessidades reais do setor, foram monitoradas duas pontes rodoviárias e uma estação metroviária, sendo utilizada instrumentação avançada baseada em sensores e equipamentos ópticos e elétricos, permitindo a medição de grandezas como deformação, temperatura, deslocamento e rotações. A experiência adquirida em campo encontra-se descrita, apresentando-se a estrutura e componentes dos modernos sistemas de monitoração e os principais resultados decorrentes da sua aplicação nas obras monitoradas. Nesse contexto, os sistemas computacionais construídos demonstraram ser úteis ferramentas, auxiliando nas diversas fases da monitoração estrutural, desde a aquisição até a interpretação dos resultados. / This work presents the development of computational systems to support acquisition, visualization, and treatment of data from health monitoring systems of civil structures. With these systems, it is possible to acquire, to visualize, and to filter monitored data. It is also possible to evaluate the influence of temperature, shrinkage and creep in structural elements. The goal is the development of tools to fulfill real needs. For that, two bridges and a subway station were monitored using advanced instrumentation based on optical and electrical sensors. The acquired experience in field is described, presenting the structure and the various components of modern structural health monitoring systems, as well as the main results of application in the monitored structures. In that context, the built computational systems demonstrated to be very useful, aiding in the several phases of the structural monitoring from the acquisition to the interpretation of the results.

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