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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.
331

An interactive PC-based network management and control package using a database management system

Wilcox, Russ Mark, 1957- January 1988 (has links)
The growing widespread use of data communication networks has led to increased reliance on the availability of network resources. The network itself is a critical resource which must be managed in a timely and effective manner. In order to manage the network effectively, the network manager must have powerful tools that present network information in a fast and logical way. The work presented here is the design and development of a network management tool for Sytek broadband networks. The Sytek Network Management Package (SNMP) incorporates a commercial database management system, Rbase System V, and menu oriented management functions for the University of Arizona Sytek broadband networks. The SNMP is written in C and executes on a PC connected to the Sytek network. The SNMP allows a network manager to manage both the Sytek LocalNet 20 and System 2000 networks.
332

Astrometric telescope simulator for the design and development of telescope teleoperation

Lew, Alfie Katat, 1960- January 1988 (has links)
A real-time discrete-event simulation model is built to emulate the functional operations of the Thaw telescope of the Allegheny Observatory and its attached scientific instrument. The OASIS software system is used to communicate with the simulation model. This simulation model, written in Ada, consists of three major parts. The Command Receiver and the Data Transmitter are software written to service the incoming telecommands and outgoing telemetry, the Command Processor is the actual simulator itself consisting of a Command Retriever, a Scanner, a Parser, a Command Interpreter, and the actual Thaw telescope simulation. The motivation for our simulation model and discussion of design issues are presented in chapters 1 and 2. The details of the model are documented in chapters 3, 4, and 5. The final two chapters include examples, questions, thoughts for future work, and conclusions.
333

Neural networks approach to process control : the case of processes with long dead times

McLeod, Charles Meredith January 1999 (has links)
Thesis submitted in compliance with the requirements for the Doctor's Degree in Technology: Electrical Engineering, Technikon Natal, 1999. / This study relates to applications of static artificial neural networks (ANNs) to two basic problems of process control: (a) process model identification, and (b) optimal controller tuning. The emphasis is on model identification, where several novel techniques are introduced. A review of the use of ANNs for determining optimal controller settings is included as a logical adjunct which would make the complete system suitable for realisation as a portable or networked system. Three methods for obtaining good approximations for the parameters of first-order processes with long dead time using artificial neural networks (ANNs) are proposed and described. These are termed in this study: time-domain, frequency-domain and model-based methods. In each case the aim was to develop a brief one-shot test that could be applied with minimal disturbance to a closed loop control system. These methods build on existing techniques, but introduce the following novel aspects: 2. The frequency-domain method makes use of the first 81 components of the FFT without further selection as input to a static ANN to yield process parameter estimates. 3. The model-based method uses a simple single-neuron implementation of an ARX model and uses a static ANN to relate process parameter values to the weights of this neuron. In making the analysis, the process input and output are applied repetitively to the neuron model with delays getting progressively larger. Useful effects arising from this are explored. A technique in which ANN training sets are slightly distorted in a random way during training of a radial basis function is developed as part of the time- and frequencydomain methods. The benefits arising from this technique are demonstrated. These experimental ANN-based control methods are evaluated by means of simulations in which accuracy in the presence of measurement noise and performance with higher order processes is measured and analysed. Although the main theme of this study is first-order-plus-dead-time (FOPDT) processes, the full autotuning scheme is tested with some representative higher order processes. Finally, the composition of a complete autotuning scheme is proposed which includes the automatic generation of controller parameters by means of ANN s. / M
334

A Computer-Based Process Control System for a Target Station in a LINAC Facility

Al-Shantaf, Abdulraouf O. 05 1900 (has links)
An event-driven, sequential, process control system was designed for International Isotopes, Inc., to automate and remotely control a target station at the company's linear accelerator facility. The designed system consisted of two major sections: a software program (virtual instrument), which was developed by LabVIEW, and a hardware interface (FieldPoint Modular Distributed I/O System by National Instrument), which had to be a pre-developed system that did not require customization. The designed virtual instrument was tested on a simulation model that mimed the target station. The result was a valid design.
335

Stereo vision based target tracking for a gun turret utilizing low performance components

26 February 2009 (has links)
M.Ing.
336

Controle com Estrutura Variável e Modos Deslizantes Aplicado em Sistema de Suspensão Ativa /

Fernandes, Ueslei Barbosa. January 2013 (has links)
Orientador: José Paulo Fernandes Garcia / Banca: Marcelo Carvalho Minhoto Teixeira / Banca: Alfredo Del Sole Lordelo / Resumo: Utilizando as técnicas de Controle com Estrutura Variável e Modos Deslizantes (CEV/MD) é proposta aqui uma aplicação das mesmas em um sistema que representa 1/4 do modelo de Suspensão Ativa de um veículo. Teoria e projeto de preditores contínuo são apresentados com o intuito de obter bom desempenho na presença de atrasos no controle ou atrasos na aquisição de dados do sistema. Com a finalidade de verificar a robustez do CEV/MD é feita uma comparação com o controle LQR (Linear Quadratic Regulator) apresentando os resultados de simulações e implementações em bancada para algumas condições de operação, levando em consideração a presença de incertezas no sistema / Abstract: Using the techniques of Control with Variable Structure and Sliding Mode (VSC/SM) is proposed here an implementation in a system that represents 1/4 of the model of an Active Suspension of a vehicle. Theory and design of continuous predictors are presented in order to obtain good performance in the presence of control delays or delays in the data acquisition system. In order to verify the robustness of the VSC/SM a comparison with the LQR control (Linear Quadratic Regulator) in presented good results of simulations and implementations for some operating conditions, taking into account the presence of uncertainties in the system, illustrated the proposed method / Mestre
337

Detecção robusta de falhas através de filtros H 'infinito': implementação prática em um helicóptero 3-DOF de bancada e em um servosistema /

Soto Pereyra, Herbert. January 2013 (has links)
Orientador: Edvaldo Assunção / Co-orientador: Emerson Ravazzi Pires da Silva / Banca: Marcelo Carvalho Minhoto Teixeira / Banca: Cristiano Quevedo Andrea / Resumo: Neste trabalho foi aplicado um método para detecção de falhas utilizando-se filtros H'infinito', no helicóptero de bancada 3-DOF e no servomotor Shake table II, equipamentos da Quanser R . Para o helicóptero foram impostos dois tipos de falhas. No primeiro caso, foi projetado um filtro H'infinito' para a detecção de falha no motor traseiro da aeronave. No segundo caso, foi projetado um filtro H'infinito' para a detecção de falhas no sensor do ângulo de viagem, considera-se ainda que o modelo do helicóptero possui uma incerteza do tipo politópica. Nos dois casos, o helicóptero também está sujeito a uma perturbação exógena. Para o servomotor Shake table II foi projetado um filtro H'infinito' para a detecção de falha no atuador. A metodologia se mostra eficiente na prática para os tipos de falhas impostas. / Abstract: In this work, it was implemented a method for fault detection via H'infinit' filters in a 3-DOF helicopter model and a servomotor Shake table II, facilities from Quanser R . For the helicopter were imposed two types of faults. In the first case, an H'infinit' filter was designed for the fault detection in the back motor of the aircraft. In the second case, an H'infinit' filter was designed for the fault detection in the sensor travel angle, also considering that the helicopter model has a polytopic uncertainty. In both cases, the helicopter is also subjected to an exogenous disturbance. For the servomotor Shake table II an H'infinit' filter was designed for the fault detection in the actuator. The methodology was efficient for these faults imposed. / Mestre
338

Positioning and vibration control of a flexible structure in slewing motion by applying Shape Memory Alloys /

Janzen, Frederic Conrad. January 2016 (has links)
Orientador: José Manoel Balthazar / Banca: Angelo Marcelo Tusset / Banca: Vinicius Piccirillo / Banca: Airton Nabarrete / Banca: Atila Madureira Bueno / Abstract: Flexible structures with slewing motion has been found with increasing frequency in various types of applications, because they are more efficient than their rigid competitors. The study of these systems is important because of the vibrations coming from the mass reduction of structures. Many works have been published presenting control techniques applied in reducing the effects of these vibrations. Several studies demonstrate the application of intelligent materials as actuators for this application. This paper presents a proposal for controlling the angular positioning and vibration of a flexible structure in slewing motion. For such compounds an intelligent actuator materials known as Shape Memory Alloy is employed to control the vibration of the flexible structure. To control the system, the control technique known as State Dependent Ricatti Equation (SDRE), is applied to the control. In order to analyse the dynamics of the system with the proposed control the mathematical modelling of the system is considered and its validation by developed an experimental prototype. Numerical simulations are carried out to analyse the viability of the control and experimental tests are performed in order to validate the theoretical model and the proposed control / Resumo: Estruturas flexíveis com movimento de rastreamento tem sido encontradas com frequências cada vez maior em diversos tipos de aplicações, por serem mais eficientes do que suas concorrentes rígidas. O estudo desses sistemas é importante por conta das vibrações advindas da redução de massa das estruturas. Muitos trabalhos têm sido publicados apresentando técnicas de controle aplicadas na redução dos efeitos dessas vibrações. Vários trabalhos demonstram a aplicação de materiais inteligentes como atuadores para esse tipo de aplicação. Sendo assim, o presente trabalho apresenta uma proposta para o controle do posicionamento angualar e da vibração de uma estrutura flexível em movimento de rastreamento. Para tal, atuadores compostos de um material inteligente conhecido como Liga com Memória de Forma são empregados para o controle da vibração da estrutura flexível. Com relação ao controle, a técnica de controle conhecida como Equações de Ricatti Dpenedentes dos Estados (SDRE) é aplicada para o controle. Com o objetivo de analisar a dinâmica do sistema como controle proposto considera-se a modelagem matemática do sistema e sua validação através do desenvolvido de um protótipo experimental. Simulações numéricas são realizadas para analisar a viabilidade do controle proposto e testes experimentais são realizados com a finalidade de validar o modelo teórico e a proposta de controle / Doutor
339

Utveckling av Reglersystem för ett Labyrintspel : Modellbaserad design i praktiken / Development of an Automatic Control System for a Labyrinth Game

Nådin, Mikael, Ericsson, Kristian January 2019 (has links)
This thesis evaluates two automatic control systems, PID and LQ, for the purpose of controlling the steel marble in a Brio labyrinth game. The objective has been for these automatic control strategies to bring the marble through the labyrinth and examine how well they handle this problem. A mathematical model of the problem was derived and a detailed model of the labyrinth game was established in Mathworks software Simscape to streamline the development of the structural design and control system. Based on the Simscape model, the labyrinth game was modified with hardware necessary to perform the task. Before the development of the control system commenced, tests were carried out to study the marbles movement in the two models compared with the labyrinth game. This proved that the friction in the labyrinth game is non-linear compared to the models which both showed similar behavior. The control system was then implemented to be tested and evaluated in the Simscape model as well as the labyrinth game. In the Simscape model, they both perform equally well and the PID- and LQ-controller can easily bring the marble through the labyrinth. In the labyrinth game, the LQ controller succeeds in bringing the marble through the labyrinth in 45\% of cases, while the corresponding for the PID controller is 25\%. The LQ controller was the one that generally had the best performance and was able to handle the marbles movement despite the non-linearities. The PID controller's performance was poorer, which is largely due to said non-linearities but also noise in the system, which the LQ controller is not affected as much by. The study shows that non-linearities such as friction are difficult to model. The model-based design is a good method but can be time consuming and the end result can make it difficult to motivate in many cases.
340

Literature Survey and the Conceptual Design of an Unmanned Arctic Ocean Scientific Vessel

Unknown Date (has links)
In this paper, the possibility of using a Small Water-plane Area Twin Hull (SWATH) as an unmanned Arctic scientific research vessel is analyzed. Before carrying out the stability analysis of the SWATH ship, this paper briefly outlines the importance of the Arctic survey, which guides the importance of the new research ship for Arctic scientific exploration. In addition to being used as a long-tern monitoring and data collection platform, it is also used as a recovery mothership for autonomous equipment such as an AUV. After briefly introducing the basic background of a SWATH, it’s advantages and disadvantages are enumerated and analyzed, and a combination of theoretical and practical tests are used to conduct a brief analysis and summary of the reasons for the appearance of trim by head arising from SWATH navigation. Trim by head occurs when a vessel incline such that its plane of flotation is not coincident with its mean waterline plane. In terms of theory, hydrodynamic equations are used to theoretically deduce the SWATH state of navigation and get the corresponding characteristic equation. Finally, a new type USV be designed conceptionally and be created as a model by Solid-work software. Conceptual design combines the advantages of SWATH and remedy deficiency of its longitudinal stability. The theoretical calculation and analysis of the struts of the conceptual model proves that the oblique struts structure can effectively improves the transverse stability of the model, and with the help of the special slender ellipse structure which is installed on the model’s struts, the righting moment of the model is increased when it’s heeling during a large angle. The hydrodynamic analysis of the conceptual model is carried out by Star- CCM software. The simulation results also prove the effectiveness of stabilizer fins to the longitudinal stability of the conceptual design and reflects the data information of the model in terms of resistance and motion state. At last, we have a general understanding of the performance characteristics of the conceptual model by analysis the feedback data, which provides reliable support for future improvement and optimization. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

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