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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.
421

Advanced Real-Time Battery State Estimation for a Hybrid Aircraft

Hosseininejad, Reza January 2025 (has links)
Canada's aviation industry aims to reduce its carbon footprint while maintaining safety and operational standards. Hybrid and electric aircraft offer a promising solution to reducing the environmental impact of conventional aviation. However, current limitations in battery technology and the robustness of battery management systems in monitoring and estimating battery states cause significant challenges for their adoption in aviation applications. This research focuses on developing an advanced state of charge (SoC) estimation method for Li-ion batteries used in hybrid aircraft. A new approach is proposed that integrates a merged set of equivalent circuit models capable of simulating battery dynamics at both the cell and module levels. In addition, an innovative dual filter involved in interactive multiple model (IMM) frameworks is introduced, equipped with advanced filtering approaches such as smooth variable structure filter (SVSF). This framework ensures accurate SoC estimation even under varying and harsh operating conditions by testing all developed algorithms in real-time. The developed model is much more accurate than the existing SoC estimation algorithms in the aircraft battery management system. These findings increase the understanding of battery performance in specific aviation conditions and help develop safer and more advanced condition monitoring and estimation methods for hybrid and electric aircrafts. / Thesis / Master of Applied Science (MASc)
422

Simulation of a Wireless Communication System in GNU Radio vs Matlab Simulink : Simulating IEEE 802.11 and 4G

Levin, Bashar January 2024 (has links)
Denna studie genomför en detaljerad undersökning av två olika plattformar för programvarudefinierad radio (SDR), GNU Radio och Simulink, för att avgöra vilken som är mest lämpad för integration i en specifik kurs inom läroplanen vid mittuniversitet. Utvärderingen fokuserar på nyckelprestandamått såsom beräkningskapacitet, simuleringens hastighet och visualiseringsförmåga, vilket ger en omfattande jämförelse mellan dessa två plattformar. Undersökningen inleds med att simulera det fysiska lagret av WiFi, vilket är ett grundläggande krav för kursens laboratoriearbete. Studiens omfattning utvidgas sedan för att inkludera simuleringar av andra nätverkstekniker som 4G. Denna expansion syftar till att samla in omfattande data för en mer noggrann jämförelse och för att grundligt utvärdera varje plattforms förmåga att hantera olika nätverkssimuleringar. Dessutom fördjupar studien sig i olika simuleringstekniker genom att diskutera två distinkta angreppssätt till SDR-simuleringar, vilket belyser deras respektive styrkor och tillämpbarhet i ett utbildningssammanhang. Det slutgiltiga målet med denna forskning är att avgöra om GNU Radio erbjuder betydande fördelar jämfört med MATLABs Simulink och om det bör ersätta Simulink som det primära verktyget som används i denna kurs. I förväntan på potentiella förändringar har nya alternativa laborationsinstruktioner för GNU Radio också utvecklats och presenterats. Dessa instruktioner är utformade för att underlätta en smidig övergång om universitetet beslutar att anta GNU Radio, för att säkerställa att utbildningsmålen fortsätter att uppnås på ett effektivt och effektivt sätt. Även om studien visar att GNU Radio erbjuder bättre beräkningskapacitet var själva simuleringsprocessen något svårare. De två plattformarna uppnådde nästan samma resultat, men GNU Radio krävde extra arbete. Med tanke på att inlärningsresultaten var liknande men inlärningsprocessen med GNU Radio var mer komplicerad bedömdes GNU Radio som olämplig för denna kurs. / This study conducts a detailed examination of two distinct Software Defined Radio (SDR) platforms, GNU Radio and Simulink, to ascertain which is more suited for integration into a specific course within the curriculum at Mid University. The evaluation focuses on key performance metrics such as computing efficiency, simulation speed, and visualization capabilities, providing a comprehensive comparison between these two platforms. The investigation begins by simulating the physical layer of WiFi, which is a fundamental requirement of the course laboratory work. The scope of the study is then broadened to include simulations of other network technologies like 4G. This expansion aims to collect extensive data for a more accurate comparison and to thoroughly evaluate the capabilities of each platform in handling various network simulations. Moreover, the study delves into different simulation methodologies by discussing two distinct approaches to SDR simulations, highlighting their respective strengths and applicabilities in an educational context. The ultimate objective of this study is to determine whether GNU Radio offers a significant advantage over MATLAB’s Simulink and if it should replace Simulink as the primary tool used in this course. In anticipation of potential changes, new alternative laboratory instructions for GNU Radio are also developed and presented. These instructions are designed to facilitate a smooth transition should the university decide to adopt GNU Radio, ensuring that educational goals continue to be met efficiently and effectively. While the study shows that GNU Radio offers better computing efficiency, the process of simulating was somewhat more challenging. The two platforms accomplished almost the same tasks, but GNU Radio required extra effort. Considering that the learning outcomes were similar but the learning process with GNU Radio was more difficult, GNU Radio was deemed unsuitable for this course.
423

Resilience of Microgrid during Catastrophic Events

Black, Travis Glenn 05 1900 (has links)
Today, there is a growing number of buildings in a neighborhood and business parks that are utilizing renewable energy generation, to reduce their electric bill and carbon footprint. The most current way of implementing a renewable energy generation is to use solar panels or a windmill to generate power; then use a charge controller connected to a battery bank to store power. Once stored, the user can then access a clean source of power from these batteries instead of the main power grid. This type of power structure is utilizing a single module system in respect of one building. As the industry of renewable power generation continues to increase, we start to see a new way of implementing the infrastructure of the power system. Instead of having just individual buildings generating power, storing power, using power, and selling power there is a fifth step that can be added, sharing power. The idea of multiple buildings connected to each other to share power has been named a microgrid by the power community. With this ability to share power in a microgrid system, a catastrophic event which cause shutdowns of power production can be better managed. This paper then discusses the data from simulations and a built physical model of a resilient microgrid utilizing these principles.
424

Simulink Erweiterungsblockbibliothek, Funktionsplan

Geitner, Gert-Helge 06 August 2013 (has links) (PDF)
Das Softwarewerkzeug FUP Blockbibliothek wurde für Entwurf, Simulation, Echtzeitkodegenerierung und Dokumentation von ereignisgesteuerten Systemen, speziell in Maschinenbau, Mechatronik und Elektrotechnik entwickelt. Es stellt eine Erweiterung zu MATLAB /Simulink dar und bietet eine umfangreiche Entwurfsunterstützung einschließlich Werkzeugen zur Erkennung von Eingabe- und Strukturfehlern. Die graphische Darstellung (Blockikonen) lehnt sich an die VDI / VDE - Richtlinie 3684 "Beschreibung ereignisgesteuerter Bewegungsabläufe mit Funktionsplänen" an.
425

Modelagem e implementação de um sistema de processamento digital de sinais baseado em FPGA para geração de imagens por ultrassom usando Simulink / Modeling and implementation of a FPGA-based digital signal processing for ultrasound imaging using Simulink

Ferreira, Breno Mendes 04 April 2017 (has links)
O ultrassom (US) é uma técnica bem consolidada que vem sendo amplamente utilizada para teste, caracterização e visualização de estruturas internas de materiais biológicos e não biológicos. Na Universidade Tecnológica Federal do Paraná, o grupo de pesquisa do US desenvolveu o sistema ULTRA-ORS que, apesar de adequado para pesquisa relacionada à excitação e recepção multicanal, possui tempo de computação muito elevado, devido a processamento em computador pessoal. Este trabalho apresenta a modelagem, implementação e validação de um sistema de processamento digital de sinais baseado em dispositivo FPGA (Field-Programmable Gate Array) de alto desempenho para reconstrução de imagens por US através da técnica beamforming. O software Simulink e a ferramenta DSP Builder foram empregados para simulação e transformação dos seguintes modelos em linguagem de descrição de hardware: filtro digital FIR (Finite Impulse Response), filtro de interpolação CIC (Cascaded Integrator-Comb), atraso variável, apodização, somatório coerente, decimação, demodulação com detecção de envoltória e compressão logarítmica. Após validação no Simulink, o projeto foi sintetizado para uma FPGA Stratix IV e implementado na placa Terasic DE4-230. A ferramenta SignalTap II do software Quartus II foi utilizada para aquisição dos sinais processados pela FPGA. Para avaliação gráfica e quantitativa da acurácia deste método, foram empregados dados brutos reais de US, adquiridos do ULTRA-ORS com frequência de amostragem de 40 MHz e resolução de 12 bits, e a função de custo da raiz quadrada do erro quadrático médio normalizado (NRMSE) em comparação com as mesmas funções implementadas através de scripts no Matlab. Como resultado principal do modelamento, além das respostas individuais de cada bloco implementado, são apresentadas as comparações entre as imagens reconstruídas pelo ULTRA-ORS e pelo processamento em FPGA para quatro janelas de apodização. A excelente concordância entre os resultados simulados e experimentais com valores de NRMSE inferiores à 6,2% e latência total de processamento de 0,83 µs corroboram a simplicidade, modularidade e efetividade do modelamento proposto para utilização em pesquisas sobre o processamento de sinais de US para reconstrução de imagens em tempo real. / Ultrasound (US) is a well-established technique that has been widely used for testing, characterizing and visualizing internal structures of biological and non-biological material. The US research group of the Federal University of Technology - Paraná developed the ULTRA-ORS system, which, although suitable for research related to multichannel excitation and reception, uses a large computing time, due to the personal computer processing. This research presents the modeling, implementation and validation of a digital processing system of signals based on a FPGA (Field-Programmable Gate Array) device of high performance for the reconstruction of images through US, using the beamforming technique. The software Simulink and the tool DSP Builder were used for simulation and transformation of the following models in hardware description language: digital filter FIR (Finite Impulse Response), CIC (Cascaded Integrator-Comb) Interpolation filter, variable delay, apodization, coherent summation, decimation, demodulation with envelope detection and logarithmic compression. After the Simulink validation, the design was synthesized for a Stratix IV FPGA and implemented on the Terasic DE4-230 board. The tool SignalTap II in the software Quartus II was used to acquire the processed signals from the FPGA. For the graphic and quantitative evaluation of the accuracy of this method, we used real raw US data, acquired from the ULTRA-ORS with sampling frequency of 40 MHz and 12-bit resolution, and the normalized root mean squared error (NRMSE) in comparison with the same functions implemented through scripts in Matlab. As a main result of the modeling, in addition to the individual responses of each implemented block, comparisons between the reconstructed images by ULTRA-ORS and FPGA processing for four apodization windows are presented. The excellent agreement between the simulated and experimental results with NRMSE values lower than 6.2% and total processing latency of 0.83 µs corroborates the simplicity, modularity and effectiveness of the proposed modeling for use in US signal processing research for real-time image reconstruction.
426

Modelagem e implementação de um sistema de processamento digital de sinais baseado em FPGA para geração de imagens por ultrassom usando Simulink / Modeling and implementation of a FPGA-based digital signal processing for ultrasound imaging using Simulink

Ferreira, Breno Mendes 04 April 2017 (has links)
O ultrassom (US) é uma técnica bem consolidada que vem sendo amplamente utilizada para teste, caracterização e visualização de estruturas internas de materiais biológicos e não biológicos. Na Universidade Tecnológica Federal do Paraná, o grupo de pesquisa do US desenvolveu o sistema ULTRA-ORS que, apesar de adequado para pesquisa relacionada à excitação e recepção multicanal, possui tempo de computação muito elevado, devido a processamento em computador pessoal. Este trabalho apresenta a modelagem, implementação e validação de um sistema de processamento digital de sinais baseado em dispositivo FPGA (Field-Programmable Gate Array) de alto desempenho para reconstrução de imagens por US através da técnica beamforming. O software Simulink e a ferramenta DSP Builder foram empregados para simulação e transformação dos seguintes modelos em linguagem de descrição de hardware: filtro digital FIR (Finite Impulse Response), filtro de interpolação CIC (Cascaded Integrator-Comb), atraso variável, apodização, somatório coerente, decimação, demodulação com detecção de envoltória e compressão logarítmica. Após validação no Simulink, o projeto foi sintetizado para uma FPGA Stratix IV e implementado na placa Terasic DE4-230. A ferramenta SignalTap II do software Quartus II foi utilizada para aquisição dos sinais processados pela FPGA. Para avaliação gráfica e quantitativa da acurácia deste método, foram empregados dados brutos reais de US, adquiridos do ULTRA-ORS com frequência de amostragem de 40 MHz e resolução de 12 bits, e a função de custo da raiz quadrada do erro quadrático médio normalizado (NRMSE) em comparação com as mesmas funções implementadas através de scripts no Matlab. Como resultado principal do modelamento, além das respostas individuais de cada bloco implementado, são apresentadas as comparações entre as imagens reconstruídas pelo ULTRA-ORS e pelo processamento em FPGA para quatro janelas de apodização. A excelente concordância entre os resultados simulados e experimentais com valores de NRMSE inferiores à 6,2% e latência total de processamento de 0,83 µs corroboram a simplicidade, modularidade e efetividade do modelamento proposto para utilização em pesquisas sobre o processamento de sinais de US para reconstrução de imagens em tempo real. / Ultrasound (US) is a well-established technique that has been widely used for testing, characterizing and visualizing internal structures of biological and non-biological material. The US research group of the Federal University of Technology - Paraná developed the ULTRA-ORS system, which, although suitable for research related to multichannel excitation and reception, uses a large computing time, due to the personal computer processing. This research presents the modeling, implementation and validation of a digital processing system of signals based on a FPGA (Field-Programmable Gate Array) device of high performance for the reconstruction of images through US, using the beamforming technique. The software Simulink and the tool DSP Builder were used for simulation and transformation of the following models in hardware description language: digital filter FIR (Finite Impulse Response), CIC (Cascaded Integrator-Comb) Interpolation filter, variable delay, apodization, coherent summation, decimation, demodulation with envelope detection and logarithmic compression. After the Simulink validation, the design was synthesized for a Stratix IV FPGA and implemented on the Terasic DE4-230 board. The tool SignalTap II in the software Quartus II was used to acquire the processed signals from the FPGA. For the graphic and quantitative evaluation of the accuracy of this method, we used real raw US data, acquired from the ULTRA-ORS with sampling frequency of 40 MHz and 12-bit resolution, and the normalized root mean squared error (NRMSE) in comparison with the same functions implemented through scripts in Matlab. As a main result of the modeling, in addition to the individual responses of each implemented block, comparisons between the reconstructed images by ULTRA-ORS and FPGA processing for four apodization windows are presented. The excellent agreement between the simulated and experimental results with NRMSE values lower than 6.2% and total processing latency of 0.83 µs corroborates the simplicity, modularity and effectiveness of the proposed modeling for use in US signal processing research for real-time image reconstruction.
427

Modelling and Design of a Test Rig to investigate the dynamic behaviour of a Servo driven Powertrain / Modellierung und Entwurf eines Versuchsstandes zur Untersuchung des dynamischen Verhaltens eines servogetriebenen Antriebsstranges

Wittwer, Max 26 March 2018 (has links) (PDF)
In the present work a simulation model for examining the fundamental dynamic behaviour of a servo driven powertrain is developed. This powertrain consists of a permanent magnet synchronous motor, a cycloidal gearbox and a torque motor to apply a load. On basis of this model the selection of components for the design of a test rig is possible. This leads to the constructive draft of the test rig. In order to model the system, the fundamentals give a brief overview of the components incorporated in the test rig system. With ais of the specified task the simulation purpose is defined and the modelling process enabled. The subsequent system analysis is performed intensively to decompose the system into subsystems, which are then investigated to find the optimal modelling approach for the given simulation task. Particular emphasis is put on the investigation of the cycloidal gearbox subsystem and it shows, that approaches for modelling the dynamic behaviour of the gearbox as a whole have only been published partially. Therefore, the available modelling approaches are analysed and suitable models are developed as conceptual models. Those will be formalised and implemented in Matlab/Simulink. The model is verified and simulation experiments are performed, that help in the selection of suitable test rig components. On basis of a flexible test rig, finally the constructive draft is presented.
428

Modelling and Design of a Test Rig to investigate the dynamic behaviour of a Servo driven Powertrain

Wittwer, Max 14 December 2017 (has links)
In the present work a simulation model for examining the fundamental dynamic behaviour of a servo driven powertrain is developed. This powertrain consists of a permanent magnet synchronous motor, a cycloidal gearbox and a torque motor to apply a load. On basis of this model the selection of components for the design of a test rig is possible. This leads to the constructive draft of the test rig. In order to model the system, the fundamentals give a brief overview of the components incorporated in the test rig system. With ais of the specified task the simulation purpose is defined and the modelling process enabled. The subsequent system analysis is performed intensively to decompose the system into subsystems, which are then investigated to find the optimal modelling approach for the given simulation task. Particular emphasis is put on the investigation of the cycloidal gearbox subsystem and it shows, that approaches for modelling the dynamic behaviour of the gearbox as a whole have only been published partially. Therefore, the available modelling approaches are analysed and suitable models are developed as conceptual models. Those will be formalised and implemented in Matlab/Simulink. The model is verified and simulation experiments are performed, that help in the selection of suitable test rig components. On basis of a flexible test rig, finally the constructive draft is presented.:1 Introduction 1.1 Motivation 1.2 Procedure 2 Fundamentals 2.1 Definitions 2.2 Modelling 2.3 Servo Drive 2.3.1 Introduction 2.3.2 Permanent Magnet Synchronous Motor 2.3.3 Servo Inverter 2.3.4 Control System 2.4 Torque Motor 2.5 Gearbox 3 Specified Task 4 System Analysis 4.1 Introduction 4.2 Servo Inverter 4.3 Control System 4.4 Servo Motor 4.5 Transmission Elements 4.6 Cycloidal Gearbox 5 Model Formalisation 5.1 Introduction 5.2 Servo Inverter 5.3 Control System 5.4 Servo Motor 5.5 Transmission Elements 5.6 Cycloidal Gearbox 6 Model Implementation 6.1 Introduction 6.2 Servo Inverter 6.3 Control System 6.4 Servo Motor 6.5 Transmission Elements 6.6 Cycloidal Gearbox 7 Simulation 7.1 Introduction 7.2 Solver 7.3 Verification 7.4 System Evaluation 7.4.1 Sensitivity Analysis 7.4.2 Stability Analysis 8 Design of the Test Rig 8.1 Selection of the components 8.2 Constructive Draft 9 Summary and Outlook
429

Simulink Erweiterungsblockbibliothek, Funktionsplan: FUP Blockbibliothek V. 2.3

Geitner, Gert-Helge January 2004 (has links)
Das Softwarewerkzeug FUP Blockbibliothek wurde für Entwurf, Simulation, Echtzeitkodegenerierung und Dokumentation von ereignisgesteuerten Systemen, speziell in Maschinenbau, Mechatronik und Elektrotechnik entwickelt. Es stellt eine Erweiterung zu MATLAB /Simulink dar und bietet eine umfangreiche Entwurfsunterstützung einschließlich Werkzeugen zur Erkennung von Eingabe- und Strukturfehlern. Die graphische Darstellung (Blockikonen) lehnt sich an die VDI / VDE - Richtlinie 3684 "Beschreibung ereignisgesteuerter Bewegungsabläufe mit Funktionsplänen" an.:Einführung S. 3 Wesentliche Eigenschaften S. 4 Anwendungshinweise S. 6 Blockbibliothek S. 11 Beispiele S. 12 Blockbeschreibungen S. 33
430

Способы обеспечения надежности современных динамических микросхем памяти : магистерская диссертация / Ways to ensure the reliability of today's dynamic memory chips

Хомутов, К. И., Khomutov, K. I. January 2016 (has links)
Discusses the structure and topology of dynamic memory chips, the impact of the environment on the information storage process, ways to control and correct errors that occur during storage of data; in Matlab / Simulink, a model is constructed of dynamic memory cells in conditions close to the natural background radiation; a comparative analysis of noise immunity in the absence of storage and use of the Hamming code. / Рассматриваются структура и топология микросхем динамической памяти, влияние внешней среды на процесс хранения информации, способы контроля и исправления ошибок, возникающие при хранении данных; в среде Matlab/Simulink построена модель ячейки динамической памяти в условиях приближенных к естественному радиационному фону; проведен сравнительный анализ помехоустойчивости хранения данных при отсутствии и использовании кода Хемминга.

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