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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.
41

Integração de Sistemas de Identificação Automáticos

Mota, Nuno Miguel Silva January 2010 (has links)
Tese mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universiade do Porto. 2010
42

Évaluation des bornes des performances temporelles des Architectures d'Automatisation en Réseau par preuves itératives de propriétés logiques

Ruel, Silvain 09 July 2009 (has links) (PDF)
Ce mémoire de thèse propose une approche pour l'obtention des bornes des performances temporelles d'une Architecture d'Automatisation en Réseau par preuves itératives de propriétés d'atteignabilité sur un modèle formel de l'architecture. Ces propriétés d'atteignabilité sont définies grâce à un automate observateur temporisé et paramétré, dont les gardes de certaines transitions sont fonction d'un paramètre temporel. A chaque itération, les résultats de preuves permettent de déterminer la valeur de ce paramètre pour la prochaine itération ; un algorithme de recherche par dichotomie assure la convergence des itérations. La mise en œuvre de cette approche sur des architectures de taille non triviale a nécessité le développement d'une méthode d'abstraction qui comporte deux étapes : simplification de la structure et modification des modèles formels des composants figurant dans la structure simplifiée, ceci afin de prendre en compte les phénomènes de concurrence entre requêtes émises par différents composants. Ces contributions formelles et méthodologiques ont été validées expérimentalement par le traitement de plusieurs cas de taille et complexité croissantes, basés sur le protocole Modbus TCP/IP.
43

Porting Linux on ARM-Based Micro-controllers

Tsai, Ju-Chin 30 July 2006 (has links)
More and more embedded systems choose ARM-based micro-controllers as CPU. If no embedded OS built with the system, the application scope will be restricted. Therefore, the need of embedded OS is vital. There are many embedded OS¡¦s in the market, but the embedded Linux has many advantages and is widely accepted. Commercial embedded Linux takes less refund than other embedded OS¡¦s. The kernel and most applications are distributed in GPL open source copyright, and is highly portable to many machine platforms. Presently, the hardware key-technology is highly skilled. The margin of 3C industrial has gone down rapidly. Therefore, people focus on adapting integrated technology to practicality and innovation to make cost down. Developers choose appropriate ARM micro-controllers according to demanding functionality of their products. The microcontroller is not necessary running with Linux distribution. Two approaches can be used to resolve the embedded OS issue. The first approach is porting Linux to the platform without any refund. The second approach is to pay for commercial Linux. Embedded system peripheral devices aim at powerful functionalities and economy. For instance, UART interface is cheap and low data transfer rate. The target board communicates with host via RS-232. RS-232 acts as serial console to play dumb terminal under Linux. Industrial applications often make use of RS-xxx for UART physical transmission layer. For instance, RS-485 applies modbus protocol to build cheap monitor systems. Network transmission is a necessary function, and it generally achieves high data transfer rate application through Ethernet. The UNIX-like network socket has served network application very well. Embedded systems are usually diskless systems. In order to keep permanent data, using flash memory as block disk system is a widely adapted strategy and which operates flash memory through MTD subsystems¡][28]¡^. An MTD subsystem contains two different modules, ¡§user¡¨and ¡§driver¡¨. In the driver module, CFI¡][40]¡^ is applied to probe flash chip, partition it and provide operating function. Flash translation layer and file-system are applied in the user module. MTD BLOCK is used to emulate the flash partitions as block devices which are then mounted into Linux virtual file system¡]VFS¡^with JFFS2 type, designed according to the feature of flash devices. In this thesis, we will describe in detail the procedure of porting Linux to ARM micro-controllers. The motivation of the work is introduced in chapter 1. In chapter 2, we introduce development tools and the main flow of the porting procedure. In chapter 3, we describe the LH79525 platform and the main perepherals on the target board, then introduce the ARM programmer model. In chapter 4, we examine the required knowledge and the important issues for porting ARM Linux. In chapter 5, we describe the details of porting Linux to run with Sharp LH79525, including modifying the key source codes and adjusting kernel configuration for embedding the UART, ethernet MAC, and MTD subsystem. In chapter 6, we do step-by-step validation and apply an integrated application with the LF-314CP temperature controller¡][46]¡^ by law-chain technology for the LH79525 target board running with the ported ARM Linux. In chapter 7, we present some issues for future work and improvement, then make a conclusion for the thesis.
44

Ajuste baseado em dados de controladores : o método VRFT embarcado em um aplicativo móvel

Garcia, Cristiane Silva January 2017 (has links)
O método VRFT (Virtual Reference Feedback Tuning) é um método baseado em dados utilizado para ajustar os parâmetros de um controlador. Uma das vantagens deste método é que não é necessário um conhecimento detalhado do modelo do processo a ser controlado. Neste trabalho é apresentado o desenvolvimento de um aplicativo Android que utiliza o método VRFT, e uma versão recursiva do mesmo, para ajustar os parâmetros de um controlador PID com base nos dados de entrada e saída coletados de um experimento realizado no processo. O experimento pode ser configurado, inicializado, monitorado, e interrompido através da aplicação móvel. Para viabilizar a comunicação com o controlador também foram desenvolvidos um gateway Bluetooth-Modbus e um protocolo de comunicação simples, que opera sobre o serviço de comunicação serial do protocolo Bluetooth. A solução proposta foi validada através de experimentos realizados em processos simulados e em um processo real, mostrando bons resultados em ambos os casos. / The Virtual Reference Feedback Tuning (VRFT) method is a data-driven method employed to tune the parameters of a controller. An advantage of this method lies in the fact that it does not need a detailed knowledge of the process model. This work presents the development of an Android application which employs the VRFT method and a newly developed recursive version of it to tune a PID controller based upon the data collected from an experiment conducted on the process. The experiment can be set up, started, monitored, and stopped from inside the mobile application. To communicate with the controller a Bluetooth-Modbus gateway and an application layer protocol, designed over the Bluetooth serial communication service, are employed, both newly developed. Finally, the entire solution is verified in two steps: first some experiments were conducted on a simulated process, then another experiment was conducted to tune a real commercial controller, both showing good results.
45

Ajuste baseado em dados de controladores : o método VRFT embarcado em um aplicativo móvel

Garcia, Cristiane Silva January 2017 (has links)
O método VRFT (Virtual Reference Feedback Tuning) é um método baseado em dados utilizado para ajustar os parâmetros de um controlador. Uma das vantagens deste método é que não é necessário um conhecimento detalhado do modelo do processo a ser controlado. Neste trabalho é apresentado o desenvolvimento de um aplicativo Android que utiliza o método VRFT, e uma versão recursiva do mesmo, para ajustar os parâmetros de um controlador PID com base nos dados de entrada e saída coletados de um experimento realizado no processo. O experimento pode ser configurado, inicializado, monitorado, e interrompido através da aplicação móvel. Para viabilizar a comunicação com o controlador também foram desenvolvidos um gateway Bluetooth-Modbus e um protocolo de comunicação simples, que opera sobre o serviço de comunicação serial do protocolo Bluetooth. A solução proposta foi validada através de experimentos realizados em processos simulados e em um processo real, mostrando bons resultados em ambos os casos. / The Virtual Reference Feedback Tuning (VRFT) method is a data-driven method employed to tune the parameters of a controller. An advantage of this method lies in the fact that it does not need a detailed knowledge of the process model. This work presents the development of an Android application which employs the VRFT method and a newly developed recursive version of it to tune a PID controller based upon the data collected from an experiment conducted on the process. The experiment can be set up, started, monitored, and stopped from inside the mobile application. To communicate with the controller a Bluetooth-Modbus gateway and an application layer protocol, designed over the Bluetooth serial communication service, are employed, both newly developed. Finally, the entire solution is verified in two steps: first some experiments were conducted on a simulated process, then another experiment was conducted to tune a real commercial controller, both showing good results.
46

Kybernetické prostředí pro systémy typu ICS/SCADA / Cyber-environment for systems of ICS/SCADA type

Váňa, Martin January 2019 (has links)
The thesis explores the problematics of cyber environment for the ICS/SCADA systems. First, shorter section is mainly focused on general introduction into the ICS/SCADA systems and their inner workings. Communication model of a general SCADA system and its foundational elements are explained. It is mainly theoretical passage and it serves as an introduction. It is necessary for understanding the second part which is mainly practical. The appropriate system is chosen as a first thing in the practical part of the thesis for the implementation of the whole project. There are defined criteria on which the system itself is implemented. Following that the system itself is implemented under a framework called openMUC and it is tested with help of the simulators according to the objective of the thesis.
47

Komunikační hardware pro I4.0 Barman / Communication hardware for I4.0 Barman

Kubíček, Richard January 2020 (has links)
This thesis deals with description and implementation of AAS module. This thesis describes the selection of individual components of device. This module will be a part of the testbed Barman project. This project is implemented in accordance with Industry 4.0 trends. Device will be work as reader of information and ingredients from NFC tags placed on a glass. With this information, parent cell can make decision which action will be done with glass. In this thesis, software for hardware operation with AAS module will be created and described. This program will further communicate with the parent program controlling the functionality of the cell itself.
48

Distribuované řídící systémy a jejich využití v praxi / Distributed control systems and its utilization in practise

Otčenášek, Martin January 2008 (has links)
In control technique there is evident highly expressive trend of shifting from efficient central managing systems towards smaller systems which are distributed on technology and which are connected by communication bus. There is no need to link all signals to central management system, operation is then distributed and realized directly in individual parts of technology. That’s why these systems are called distributive managing systems. Distributive managing systems are widely used not only in industrial applications but also in buildings, cars, etc..
49

Systémy ochran a vzdáleného řízení vn rozvodny s použitím ochran s komunikací Profibus a IEC61850 / Systems of protection and remote control of medium voltage substation with using protection with communication Profibus and IEC61850

Tesařík, Jan January 2014 (has links)
This Diploma thesis deals with the system for protection and remote control for MV switchgear by using protection relays with communication protocols PROFIBUS and IEC61850. The first part represents a theoretical introduction to points at issue. In the first part, the reader will get conceived with the communication standard IEC61850 and its typical architecture for MV switchgear, and also with data model based on this standard. Second part discusses the PROFIBUS communication protocol. In this part, the reader can acquire information about transmit technology and communication protocol for PROFIBUS. Last part of this theoretical chapter contains an overview on the MODBUS communication. The second part deals with the description of protection relays, which were used for the purposes of this thesis. In the first subchapter, the reader can learn about the REM620 from ABB Company, its configuration and cooperation with IEC61850 standard. Second subchapter describes the HMS Anybus communication converter. The reader will get further knowledge about description of this device and how to configure the communication protocols. In last subchapter, a description of protection relay SIPROTEC 7SJ64 produced by Siemens company is explained. With the third part starts the practical work within this thesis with protection relays. This chapter is divided into two parts; each describes different system with using the protection relays. First system contains ABB REM620 relay and HMS Anybus converter. By converting MODBUS protocol with the Anybus converter, the REM620 can be connected to PROFIBUS network. This part includes the configuration of REM620 and Anybus converter, the engineering of MODBUS and PROFIBUS protocols and testing various signals in those networks. The second system contains Siemens SIPROTEC 7SJ64 and ethernet switch. This subchapter deals with the preparation of configuration for SIPROTEC 7SJ64 and the engineering for IEC61850 communication. This part finishes with the comparing of both systems on the engineering bases. The last part of this thesis is about working with the LabVIEW instrument. Within this part, the software emulation of protection relay was made. The program offers to the user the possibility of setting input parameters as the effective values of current and voltage, the frequency and the current phase shift. Also the user can set the thresholds for protection functions, such as the Overcurrent, the Voltage and the Frequency protection. As last one, the Phase unbalance protection for the current phases is present.
50

Inteligentní elektronické zařízení REF615 / Feeder Protection Relay REF615

Holomek, David January 2015 (has links)
The main objective of this thesis is to create a monitoring system for an asynchronous motor using IED REF615. For REF615 devices it is necessary to make the appropriate configuration and connection.The device communicate with the MVI69-MNET card by Modbus/TCP protocol. The thesis describes the operation of an asynchronous motor through the use of a PowerFlex 40 frequency changer. PowerFlex 40 sends data via an Ethernet/IP connection. The thesis also describes a program in PLC for monitoring the power status of an asynchronous motor. The next part of my work is a visualization created in the FactoryTalk View Studio. In conclusion, the thesis is tested by connecting all of the components as well as all of the proposed functions.

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