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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.
51

Regulátor horkých vtoků pro vstřikovací formy plastu / Controller of hot runner for injection molds

Chrenka, Eduard January 2016 (has links)
The thesis focuses on implementation of a hot runner controller for injection molds for plastic materials with a maximum number of 56 regulated zones. The first part of the thesis deals with already existing and used solutions of the given subject. The following part of the thesis describes the principles of temperature measurement by means of thermoelectric sensors, including their linearization as well as communication protocols MODBUS, EUROMAP 17. The identification of a regulated system ( heating zone) has been carried out before the hardware design. The development process is divided into some parts : system conception, hardware design, software development. The controller consists of measuring modules designed to collect data and handle power controllers for management of performance of heating elements. The necessary calculation power is integrated into the controllling computer. All parts of a hot runner controller are implemented taking into account the costs.
52

Honeypot study of threats targeting critical infrastructure / Honeypot studie av cyberhot riktade mot kritisk infrastruktur

Alberto Scola, Carlo January 2023 (has links)
Honeypots are systems with the intent of gathering information about potential threats and, at the same time, shifting part of the attention away from the real targets. In industrial control system environments, honeypots play a significant role and can lead to further threat study while distracting potential attackers away from critical physical systems. Low-interaction honeypots are emulated systems that try to recreate a real environment by simulating applications and protocols. These types of honeypots still need improvements to be efficient, and during this thesis work the focus has been on the Conpot open-source ICS honeypot. Due to their nature, low-interaction honeypots are less appealing to potential attackers than high-interaction honeypots since they do not provide the same level of realism and can be easier discovered. Earlier works showed ways to increase the ability to attract more visitors and an improved setup of Conpot has been evaluated. Its results have been analyzed and compared with the default installation. Several advancements have been implemented as well as custom features and working functionalities, such as a customized industrial system design, improved logging, and a web API proxy. The goal of this work is to answer the investigated hypothesis which consists in finding out if an improved version of the low-interaction honeypot can yield more significant results. By evaluating the network traffic received, the outcome has been insightful and showcased a distinguished improvement over the original version of the honeypot. The ICS protocols displayed a more considerable number of interactions along with an increased amount of attacks. In conclusion, further development for the Conpot honeypot is desirable which would largely improve its performance and practicality in real-world deployments. / Honeypots är ett system med avsikten att samla information om potentiella hot och samtidigt avleda uppmärksamheten från de verkliga målen. I industriella kontrollsystemsmiljöer spelar honungskrukor en viktig roll och kan leda till ytterligare hotstudier samtidigt som potentiella angripare distraheras från viktiga fysiska system. Honeypots med låg interaktion är emulerade system som försöker återskapa verkliga miljöer genom att simulera applikationer och protokoll. Dessa typer av honeypots behöver fortfarande förbättringar för att vara effektiva, och under detta examensarbete har fokus legat på Conpot open source ICS honeypots. På grund av designbegränsningar är honeypots med låg interaktion mindre tilltalande för potentiella angripare än honeypots med hög interaktion. Tidigare arbeten har visat sätt att öka möjligheten att locka fler besökare och en förbättrad installation av Conpot har utvärderats och dess resultat har analyserats och jämförts med standardinstallationen. Flera framsteg har implementerats samt anpassade funktioner och fungerande funktioner, såsom en anpassad industriell systemdesign, förbättrad loggning och en webb-API-proxy. Målet med detta arbete är att svara på den undersökta hypotesen som går ut på att ta reda på om en förbättrad version av honungskrukan med låg interaktion kan ge mer signifikanta resultat. Genom att utvärdera den mottagna nätverkstrafiken har resultatet varit insiktsfullt och visat upp en stor förbättring jämfört med den ursprungliga versionen av honeypot. ICS-protokollen visade ett större antal interaktioner tillsammans med en ökad mängd attacker. Sammanfattningsvis är det önskvärt med en vidareutveckling av Conpot honeypot som avsevärt skulle förbättra dess prestanda och praktiska användning i den verkliga världen.
53

Internet das coisas aplicada à indústria: dispositivo para interoperabilidade de redes industriais

Keller, Armando Leopoldo 13 January 2017 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2017-04-20T13:56:57Z No. of bitstreams: 1 Armando Leopoldo Keller_.pdf: 2124143 bytes, checksum: ba23113da63873463958e38c05ddbd88 (MD5) / Made available in DSpace on 2017-04-20T13:56:57Z (GMT). No. of bitstreams: 1 Armando Leopoldo Keller_.pdf: 2124143 bytes, checksum: ba23113da63873463958e38c05ddbd88 (MD5) Previous issue date: 2017-01-13 / Nenhuma / O objetivo deste trabalho, é realizar um estudo de forma mais abrangente sobre o conceito de Internet das Coisas e seus principais protocolos. Explora-se especificamente o conceito de IoT (Internet of Things) aplicado em sistemas de automação. Para tanto é apresentada uma revisão bibliográfica sobre o assunto, explorando os diversos protocolos desenvolvidos para aplicações de IoT, caracterizando-os quanto a taxa de transmissão, eficiência, segurança e confiabilidade. Também é realizado um levantamento do cenário atual, quanto a aplicação de protocolos de IoT em sistemas de automação, sempre tendo em mente a confiabilidade do sistema. Percebe-se que um grande dificultador do uso destes tipos de protocolo em ambientes industriais é justamente a heterogeneidade das redes existentes. Diante deste problema, a proposta do trabalho é desenvolver um dispositivo que atue como middleware para a interligação de redes de automação distribuídas, no caso especificamente a rede Modbus RTU, fazendo com que esta interligação seja de forma transparente utilizando o protocolo de Internet das Coisas MQTT (Message Queuing Telemetry Transport). Este dispositivo é testado com equipamentos em um cenário real através de um estudo de caso, onde duas redes Modbus RTU de um sistema geograficamente distribuído de geração de energia solar fotovoltaica, são interligadas, permitindo a criação de uma planta virtual de geração de energia do inglês virtual power plant (VPP). Com isso é possível tratar e gerenciar os sistemas distribuídos de geração como sendo uma única unidade geradora, facilitando o despacho. Para comprovar a eficiência e a confiabilidade do sistema, foram realizados testes onde o tempo entre as requisições e respostas foi medido, e através da sua distribuição foi obtido um tempo de 2,5 segundos para obter uma comunicação com baixa taxa de perda de mensagens. Estes testes comprovam o correto funcionamento do sistema proposto. / The objective of this work is to develop a more comprehensive study on the concept of Internet of Things (IoT) and its main protocols, specifically exploring the concept of IoT applied in automation systems. A bibliographic review explores the diverse protocols developed for IoT applications, characterizing them as transmission rate, efficiency, safety and confiability. A survey of the current scenario about the application of IoT protocols in automation systems is presented, always having the system confiability in mind. The heterogenity of the existent networks makes the use of this protocols a harder task. The proposal of this work is develop a device that acts as middleware for interlink distributed automation networks, in this case the Modbus RTU networks, in a transparent way using the internet of things procol MQTT (Message Queuing Telemetry Transport). This device is tested with equipments in a real scenario trough a case study, where two Modbus RTU networks of a geographically distributed solar photovoltaic power plant, is interlinked, allowing the criation of a VPP (Virtual Power Plant). This makes possible to manage the distributed power generator systems as a single generator unit, improving the electric energy dispatch. To prove the efficiency and confiability of the system, tests were made where the time between request and response was mensured, and based on his distribution the time of 2.5 seconds was determined to have a low message loss communication. Those tests validate the proposed system and the achievement of the goals of the present work.
54

Jednoduchý průmyslový Ethernet / Industrial low complexity Ethernet system

Šustek, Vladimír January 2019 (has links)
The diploma thesis is focused on the building embedded demonstration application of the proprietary Low Complexity Ethernet module for industrial usage further called the LEN/LES 2. At the first, main used technologies such as MCU, or the lightweight IP stack is discussed, Consequently, there is detailed view on system hardware architecture proposed by hardware and software requirements. Then though part describes blocks of embedded system are in term of specific parts and hardware requirements to create universal board. Following chapters expresses first startup and known hardware bugs, LWIP implementation and MODBUS system implementation. The core of the system is the new released microcontroller an ADuCM4050 and the Low Complexity Ethernet MAC-PHY prototype block and much more dependent convenient peripherals of the MCU based application.
55

Aplikace pro obsluhu měřicích zařízení v energetice / Application for operation of measuring devices in power engineering

Ševčík, Radek January 2019 (has links)
This thesis is focused on application development with ARM processor architecture and Linux operating system. It uses cloud hosting services to build, test and deploy applications with container-based virtualization. The application communicates with smart meters on serial buses. It stores measurements in a database. It provides access to devices and measurements in internet network.
56

Analýza řídících protokolů využívaných v průmyslových aplikacích / Analysis of distributed control protocols for indistrial applications

Horych, Vladimír January 2009 (has links)
This master's thesis deals with distributed control protocols for industrial applications. It explains term distributed control system, control protocol and it is dealing with properties, frame structures and ways of communication within CAN, Modbus, IEC60870-5-101 and DLMS protocols. This thesis includes informations, which are in most cases difficult to find. Second part of the thesis is dedicated to education system. This part is contained by information about protocols and their layers based on ISO/OSI model, pictures of structure of messages, knowledge test and an application based on JavaScript language. This JavaScript application emulates behavior of workstations, which are using communication based on IEC 60870-5-101 protocol. This application can set various conditions for influence of message transfer. These conditions are setting way of message transfer, data availability, filling of workstation’s buffer or intentional damage of message's content. It also contains a large amount of context help, activated after moving mouse cursor over most of application's elements. Even visitor without great knowledge of distributed control systems should understand how this protocol works, thanks to these context help and messages printed in lower part of the application. The conclusion of this work is aimed to positive and negative features and comparison of mentioned control protocols.
57

Inteligentní převodník 0-20mA s rozhraním Ethernet / Analog 0-20mA to Ethernet convertor

Štreit, Zdeněk January 2010 (has links)
The dissertation deals with a design of an intelligent transmitter of a standard current signal with an Ethernet output port, an implementation of a web interface and Modbus TCP protocol for providing data protection. The introductory part describes standardized analogue technical signals with their possibilities, and characteristics of industrial Ethernet. The subsequent part provides an overview of alternatives to connect analogue signals to Ethernet while using various modules. The thesis continues with a suggestion of an analogue input side of the transmitter in connection with a digital module of Ethernet based on the Rabbit processor in connection with the RCM3200 module. The key part of the dissertation puts forward a proposal of the firmware transmitter and control web interface, shows ways of providing figures measured by the current loop via Ethernet interface for further processing. The final part is devoted to a description of current transmitter ultimate measurement.
58

Terminál pro testování datových přenosů vozidel MHD / Terminal for testing of data communication of public transport vehicles

Fiala, Michal January 2014 (has links)
This term paper deals with subject of wireless communication of city rail transport cars. In this paper are described individual modules for transmission and receiving of data containing communication between city rail transport cars and measures of siding switches. Then there are discussed possibilities of design of system for testing functionality of transmitting and receiving modules and the system is consequently designed. There are also described communication principles and protocol used for wireless communication and MODBUS protocol used for communication over RS-485 serial line. In the end was the system manufactured, completed and equipped with necessary software.
59

Communication and Control in Power Electronics Systems

Mitrovic, Vladimir 17 December 2021 (has links)
The demands of a modern way of life have changed the way power electronics systems work. For instance, the grid has to provide not only the service of delivering electrical energy but also the communication to enable interactions between customers and enable them to be producers of electrical energy, too. Thus, the smart grid has come into existence. The consequence of the smart grid is that consumers could be “smart.” The most obvious consumers are households, so the houses have to also be smart and must be equipped with various power electronics devices for producing and managing electrical energy. Again, all those devices have to communicate somehow and provide data for managing electrical energy in the house. Zoomed in further, novel, state-of-the-art measurement equipment could have been built from different power electronics devices, and communication among them would be necessary for good operation. Zoomed further in, communication among different pieces of power electronics devices (such as converters) could offer benefits such as flexibility, abstraction, and modularity. This thesis provides insight into different communication techniques and protocols used in power electronics systems. A top-down approach presents three different levels of communication used in real-life projects with all the challenges they bring, starting with the smart house, followed by the state-of-the-art impedance measurement unit, and finalizing with internal power electronics building block (PEBB) communication. In the case of a smart house, where the house is equipped with solar panels, charge controllers, batteries, and inverters, communication allows interoperation between different elements of the power electronics system, enabling energy management. Results show the operation of the system and energy management algorithm. A house of this type won first prize at an international competition where energy management was one of the disciplines. The impedance measurement unit consists of different power electronics devices. In this case, too, communication between devices enables the operation of the impedance measurement unit. Communication techniques used here are shown together with measurement results. Finally, inter-PEBB communication has been shown as an approach for interaction among the different elements inside the PEBB, such as controller, GDs, sensors, and actuators. Real-time communication protocol, including all challenges, is described and developed. This approach is shown to enable communication and synchronization among different nodes inside the PEBB. Communication enables all internal elements of the PEBB to be transparent outside the PEBB in the sense that data gathered from them could be reused anywhere else in the system. Also, this approach enables the development of distributed event (time) driven control, hardware and software, abstraction, high modularity, and flexibility. A very important aspect of inter-PEBB communication is synchronization. A simple technique of sharing a clock among the parts of a 6 kV PEBB has been shown. / M.S. / This thesis provides insight into different communication techniques and protocols used in power electronics systems. A top-down approach presents three different levels of communication used in real-life projects with all the challenges they bring, starting with the smart house and a custom device designed and developed to be a communication interface among different power electronics devices from different vendors, such as charge controllers or inverters, but with capabilities not only to communicate but to also provide a platform for the development of energy management algorithms used to make houses grid zero if not grid positive. Aside from the smart house, this thesis describes communication protocols and techniques used in the impedance measurement unit (IMU). This complex measurement device provides valuable and accurate impedance measurements and consists of different power electronics devices that need to communicate. Finally, at the power electronics building block (PEBB) level, real-time communication protocol with all challenges is described. Developed communication protocol provides communication and synchronization among different nodes such as GDs, sensors, and actuators inside the PEBB. This intra-PEBB communication and synchronization combined with inter-PEBB communication and synchronization provide the foundation for the development of truly distributed event- (time-) driven control as well as hardware and software abstraction.
60

Analýza provozu trakční napájecí stanice / Hybrid AC/DC,AC/AC substation operation analysis

Lakomý, Marek January 2014 (has links)
The work analyzes the operation of hybrid substations. The first chapter provides an analysis of domestic traction systems and describes in detail specific station. The next chapter follows the first in a way in which obtained parameters are converted to parameters suitable for the simulation program and presents its results. The third chapter discusses the serial communication used in one switchgear and about voltage regulator that controls one high voltage field. The last chapter verifies the simulation results obtained from the second chapter with real measurement and direct comparison is also included.

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