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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

Διαδικασία ανάπτυξης βιομηχανικών εφαρμογών ελέγχου και εργαλείο υποστήριξής της

Τρανώρης, Χρήστος Σ. 13 February 2009 (has links)
Η αναβάθμιση της διαδικασίας ανάπτυξης εφαρμογών λογισμικού που αφορούν τον έλεγχο βιομηχανικών συστημάτων, είναι ένα θέμα που απασχολεί για δεκαετίες του μηχανικούς ελέγχου αλλά και τους μηχανικούς λογισμικού. Κατά την ανάπτυξη των βιομηχανικών εφαρμογών, οι μηχανικοί καλούνται να ικανοποιήσουν πληθώρα απαιτήσεων μεταξύ των οποίων: συμβατότητα με το υπάρχον εγκατεστημένο υλικό, συμβατότητα με τις ήδη εγκατεστημένες παλαιότερες εφαρμογές και επαναχρησιμοποίηση τμημάτων λογισμικού. Για τους παραπάνω λόγους, αναζητούνται συνεχώς λύσεις οι οποίες: θα προσφέρουν μια περισσότερο φιλική προς το μηχανικό ελέγχου διαδικασία ανάπτυξης η οποία θα υποστηρίζει επεκτασιμότητα των εφαρμογών, θα διευκολύνει την επαναχρησιμοποίηση τμημάτων του λογισμικού, θα ενισχύει την συντήρηση του λογισμικού και θα είναι ανεξάρτητη από το υλικό εκτέλεσης των βιομηχανικών συστημάτων. Η International Electrotechnical Commission (IEC) για να αντιμετωπίσει τις απαιτήσεις των σύγχρονων συστημάτων δημιούργησε το πρότυπο IEC61499 το οποίο έρχεται να επεκτείνει το Function Block του IEC61131. Το IEC61499, καθορίζει μια μεθοδολογία σχεδιασμού, όπου το Function Block είναι το βασικό δομικό συστατικό για την ανάπτυξη διαλειτουργικών κατανεμημένων εφαρμογών αυτοματισμού και ελέγχου. Οι εφαρμογές ελέγχου μπορούν να υλοποιηθούν από Function Block δίκτυα διασυνδέοντας τις εισόδους και εξόδους τους. Το IEC61499 προτείνει επίσης τον σχεδιασμό εργαλείων λογισμικού για την υποστήριξη (εν μέρει αυτοματοποίηση) της διαδικασίας ανάπτυξης. Στην παρούσα διατριβή, παρουσιάζεται μια νέα προσέγγιση για τον σχεδιασμό κατανεμημένων βιομηχανικών εφαρμογών και πιο συγκεκριμένα Συστημάτων Μέτρησης και Ελέγχου Βιομηχανικών Διεργασιών1 (IPMCSs) όπως τα ορίζει το πρότυπο IEC. Η προσέγγιση εστιάζει στον ορισμό μιας μεθοδολογίας για την φάση της ανάλυσης και κύρια την τεκμηρίωση των απαιτήσεων και τον μετέπειτα μετασχηματισμό του μοντέλου ανάλυσης σε μοντέλο σχεδιασμού. Η προτεινόμενη προσέγγιση βασίζεται σε κατάλληλα οριζόμενες έννοιες και τεχνικές και αξιοποιεί τελευταίες τάσεις από το χώρο της Μηχανιστικής Λογισμικού (Software Engineering), όπως είναι η έννοια της μετα-μοντελοποίησης (Meta-modeling) όπως αυτή ορίζεται στα πλαίσια της βασισμένης σε μοντέλα ανάπτυξης (Model Driven Development) και της Unified Modeling Language (UML) και των επεκτάσεων της (UML Profiles) και εφαρμογή αυτών στο σχεδιασμό βιομηχανικών εφαρμογών. Για την ομαλή μετάβαση από τις καταγεγραμμένες απαιτήσεις σε μοντέλα σχεδιασμού τεκμηριώθηκε και παρουσιάζεται ένα σύνολο κανόνων μετασχηματισμού το οποίο περιγράφηκε αυστηρά με χρήση της Object Constraint Language. Για να αξιοποιηθεί η προτεινόμενη προσέγγιση από μηχανικούς ελέγχου, σχεδιάστηκε και υλοποιήθηκε ένα εργαλείο λογισμικού συμβατό με το πρότυπο IEC61499. Το εργαλείο που έχει το όνομα CORFU ESS έρχεται να υποστηρίξει: α) την φάση της ανάλυσης, β) τον μετασχηματισμό του μοντέλου ανάλυσης σε μοντέλο σχεδιασμού, γ) τον σχεδιασμό εφαρμογών με Function Blocks όπως ορίζει το IEC61499, δ) την κατανομή των Function Block στις συσκευές των βιομηχανικών δικτύων και ε) τον έλεγχο των τελικών Function Block δικτύων. Η προσέγγιση εφαρμόσθηκε σε μελέτες περίπτωσης για να επιδείξει την εφαρμοσιμότητα της προτεινόμενης διαδικασίας, την αποτελεσματικότητα του εργαλείου που αναπτύχθηκε και την δυνατότητα της διαδικασίας και του εργαλείου να καλύψουν απαιτήσεις μικρής ή μεγάλης κλίμακας εφαρμογών. / Following technology’s trends, engineers in the industrial and control sector continuously face problems on developing distributed industrial control applications that should meet various functional, interface, operational and performance requirements by conforming on engineering concerns such as maintainability and reliability. During the development of industrial applications, engineers deal with aspects on device compatibility, software compatibility and software reusability. To deal with these challenges, control engineers are underway in applying Software Engineering practices in the development process of distributed industrial control applications that will enhance reusability, maintainability and will be independent of the underlying platform. A proof of this motion is the standard 61499 of the International Electrotechnical Commission (IEC) which is affected from practices and current trends in Software Engineering. The IEC 61499 standard extends the FB concept of IEC1131 to share many of the well defined and already widely acknowledged benefits of concepts introduced by object technology. This standard describes also a methodology that defines the FB as the main building block and specifies the way that FBs can be used to define robust, re-usable software components that constitute complex IPMCSs. Complete control applications, can be built from networks of FBs that are formed by interconnecting their inputs and outputs. IEC 61499 proposes also that, Engineering Support Systems (ESSs) are highly required to support the whole development process. This dissertation presents a new approach for the design of distributed industrial control applications or Industrial Process Measurement and Control Systems (IPMCSs) as defined in the IEC 61499. The approach defines a methodology for the analysis phase, based on object-oriented concepts, and mainly focuses in the requirements specification and the transformation from the analysis model to the design model. The approach is based on properly defined concepts and adopts modern techniques and latest trends from Software Engineering such as the concept of metamodeling, Model Driven Development (MDL), the Unified Modeling language (UML), UML extensions as defined in UML profiles and applies them to the design of distributed industrial control applications. For the transition from requirements specification to design models a set of transformation rules is presented, formally specified by means of the Object Constraint Language, that are used to later to automate the transition process. Towards the automation and the exploitation from control engineers of the proposed approach, a prototype ESS that supports the development process and is compatible with IEC61499 was implemented. The ESS named CORFU ESS comes to support all the phases of the proposed process: the object-oriented analysis, the automated transformation process from the analysis to the design model, the design with Function Blocks as proposed from the IEC 61499 standard, the verification of Function Block diagrams and the distribution of Function Blocks to industrial field devices. In order to verify the development process, several case studies have been designed and are presented in the context of this dissertation in order to prove: the applicability of the proposed approach, the effectiveness of the implemented prototype ESS and the ability of the approach to cover small and large scale applications.
42

Identificação parcial da resposta em freqüência de sistemas multivariáveis e sintonia de controladores descentralizados

Stevanatto Filho, Luiz Carlos January 2008 (has links)
Utilização de experimentos com relés para identificação de pontos da resposta em freqüência de sistemas multivariáveis quadrados e sintonia de controladores PID descentralizados. / It use relay experiments for square multivariable system frequency response and decentralized PID controller tunning.
43

Identificação parcial da resposta em freqüência de sistemas multivariáveis e sintonia de controladores descentralizados

Stevanatto Filho, Luiz Carlos January 2008 (has links)
Utilização de experimentos com relés para identificação de pontos da resposta em freqüência de sistemas multivariáveis quadrados e sintonia de controladores PID descentralizados. / It use relay experiments for square multivariable system frequency response and decentralized PID controller tunning.
44

Controle preditivo aplicado à planta piloto de neutralização de pH. / Predictive control applied to a pH neutralization pilot plant.

Juliana Favaro 27 September 2012 (has links)
Uma das técnicas de controle avançado que vem ganhando destaque no cenário econômico e ecológico, focando maior sustentabilidade e a otimização dos processos, é o controle preditivo, o qual já vem sendo aplicado em indústrias químicas e petroquímicas. Esta dissertação trata do desenvolvimento de um controle preditivo aplicado a uma planta piloto de neutralização de pH, presente no Laboratório de Controle de Processos Industriais da Escola Politécnica da Universidade de São Paulo. O desenvolvimento do projeto pode ser dividido em quatro etapas: implementação das malhas de controle regulatório, identificação dos sistemas, construção do controlador preditivo, aplicações e análises experimentais. Na primeira etapa foi necessário estudar o sistema em questão e implementar algumas malhas internas usando controladores PID. Na segunda etapa foi realizada a identificação do modelo da planta, ressaltando que pontos de operação e ajuste de parâmetros internos são determinantes para a modelagem. Já na terceira etapa desenvolveu-se um controlador preditivo, através de softwares auxiliares como o MATLAB e o IIT 800xA da ABB, que foram utilizados para o desenvolvimento e implementação do algoritmo de controle. Por fim, na última etapa, foi feita a análise e comparação dos resultados, quando se submete à planta a um controlador PID, quando aplicado um controlador preditivo em cascata com controladores PID e quando se utiliza apenas o controlador preditivo com ação direta nos atuadores. / The predictive control is an advanced control technique which has gained evidence in the economic and ecological context because the search for sustainability and process optimization. This control has already been applied by the chemical and petrochemical industries. The purpose of this project is to develop a predictive controller which will be applied in a pH neutralization plant located in the Industrial Processes Control Laboratory at Polytechnic School of the University of São Paulo. The development of this project can be divided into four stages: implementation of regulatory control loops, identification of the system, construction of the predictive controller, applications and experimental analysis. The first step is necessary in order to study the plant and to implement some internal loops using PID controllers. In the second step, the identification process of the plant model will be done. It is important to note that operating points and internal parameter settings are very important for modeling. In the third stage, using the model obtained from the identification process, a predictive controller is built from auxiliary software such as MATLAB and IIT 800xA (by ABB), which will be used for the development and implementation of the control algorithm. Finally, the last step consists in collecting and analyzing the results of the pH neutralization plant. At this stage the responses of each controller will be compared: PID controller, MPC controller in cascade mode with PID and MPC controller acting directly on actuators.
45

Identificação parcial da resposta em freqüência de sistemas multivariáveis e sintonia de controladores descentralizados

Stevanatto Filho, Luiz Carlos January 2008 (has links)
Utilização de experimentos com relés para identificação de pontos da resposta em freqüência de sistemas multivariáveis quadrados e sintonia de controladores PID descentralizados. / It use relay experiments for square multivariable system frequency response and decentralized PID controller tunning.
46

Network security monitoring and anomaly detection in industrial control system networks

Mantere, M. (Matti) 19 May 2015 (has links)
Abstract Industrial control system (ICS) networks used to be isolated environments, typically separated by physical air gaps from the wider area networks. This situation has been changing and the change has brought with it new cybersecurity issues. The process has also exacerbated existing problems that were previously less exposed due to the systems’ relative isolation. This process of increasing connectivity between devices, systems and persons can be seen as part of a paradigm shift called the Internet of Things (IoT). This change is progressing and the industry actors need to take it into account when working to improve the cybersecurity of ICS environments and thus their reliability. Ensuring that proper security processes and mechanisms are being implemented and enforced on the ICS network level is an important part of the general security posture of any given industrial actor. Network security and the detection of intrusions and anomalies in the context of ICS networks are the main high-level research foci of this thesis. These issues are investigated through work on machine learning (ML) based anomaly detection (AD). Potentially suitable features, approaches and algorithms for implementing a network anomaly detection system for use in ICS environments are investigated. After investigating the challenges, different approaches and methods, a proof-ofconcept (PoC) was implemented. The PoC implementation is built on top of the Bro network security monitoring framework (Bro) for testing the selected approach and tools. In the PoC, a Self-Organizing Map (SOM) algorithm is implemented using Bro scripting language to demonstrate the feasibility of using Bro as a base system. The implemented approach also represents a minimal case of event-driven machine learning anomaly detection (EMLAD) concept conceived during the research. The contributions of this thesis are as follows: a set of potential features for use in machine learning anomaly detection, proof of the feasibility of the machine learning approach in ICS network setting, a concept for event-driven machine learning anomaly detection, a design and initial implementation of user configurable and extendable machine learning anomaly detection framework for ICS networks. / Tiivistelmä Kehittyneet yhteiskunnat käyttävät teollisuuslaitoksissaan ja infrastruktuuriensa operoinnissa monimuotoisia automaatiojärjestelmiä. Näiden automaatiojärjestelmien tieto- ja kyberturvallisuuden tila on hyvin vaihtelevaa. Laitokset ja niiden hyödyntämät järjestelmät voivat edustaa usean eri aikakauden tekniikkaa ja sisältää useiden eri aikakauden heikkouksia ja haavoittuvaisuuksia. Järjestelmät olivat aiemmin suhteellisen eristyksissä muista tietoverkoista kuin omista kommunikaatioväylistään. Tämä automaatiojärjestelmien eristyneisyyden heikkeneminen on luonut uuden joukon uhkia paljastamalla niiden kommunikaatiorajapintoja ympäröivälle maailmalle. Nämä verkkoympäristöt ovat kuitenkin edelleen verrattaen eristyneitä ja tätä ominaisuutta voidaan hyödyntää niiden valvonnassa. Tässä työssä esitetään tutkimustuloksia näiden verkkojen turvallisuuden valvomisesta erityisesti poikkeamien havainnoinnilla käyttäen hyväksi koneoppimismenetelmiä. Alkuvaiheen haasteiden ja erityispiirteiden tutkimuksen jälkeen työssä käytetään itsejärjestyvien karttojen (Self-Organizing Map, SOM) algoritmia esimerkkiratkaisun toteutuksessa uuden konseptin havainnollistamiseksi. Tämä uusi konsepti on tapahtumapohjainen koneoppiva poikkeamien havainnointi (Event-Driven Machine Learning Anomaly Detection, EMLAD). Työn kontribuutiot ovat seuraavat, kaikki teollisuusautomaatioverkkojen kontekstissa: ehdotus yhdeksi anomalioiden havainnoinnissa käytettävien ominaisuuksien ryhmäksi, koneoppivan poikkeamien havainnoinnin käyttökelpoisuuden toteaminen, laajennettava ja joustava esimerkkitoteutus uudesta EMLAD-konseptista toteutettuna Bro NSM työkalun ohjelmointikielellä.
47

Návrh na zavedení průmyslového řešení ISMS ve výrobní společnosti / A Proposal for Industrial ISMS Implementation in Manufacturing Company

Kulhánek, Radek January 2016 (has links)
This diploma thesis deals with industrial ISMS implementation in manufacturing company. The theoretical part of thesis summarizes the theoretical knowledge in the field of information security and industrial security. In the following section company AB Komponenty s.r.o. is analysed. Then is performed analysis of risks based on selected assets and potential threats. Followed by design of the countermeasure to minimalize potential threats.
48

Improving quality control in automation projects using simulation systems

Lönnroth, Viktor January 2021 (has links)
Automation systems are becoming more and more integrated in today’s society. The complexities of these systems are increasing and with this, the demand for high quality during the developmental phases. This poses a challenge for companies developing systems. One solution emerging form this issue is the use of simulations and virtual commissioning.  In the thesis, the process of quality control and the effective use of simulations in automation system development projects are studied. The focus lies on the software part of the systems. The study was conducted as an interview study of personnel at an automation systems development company. After conducting the interviews, the information was analyzed. This was combined with general theory regarding quality control and testing methods in software development. The test methods of the quality control process were then combined with what was required by a simulator in order to preform them.  The results of the thesis is a detailed picture of the quality control process. Systems are tested twice with the same testing hierarchy, first during development and then during commissioning. The difference is that during development, the final physical hardware and process system are not conceded to the software. This impacts the software system functionality and limiting its testability. Using simulations during development can reduce the disparity between the systems before and after deployment, improving quality. Considerations regarding the extent of simulation need to be made in order for the value of the simulators’ error removing potential to be higher than the cost of developing the simulator. / Automationssystem blir mer och mer integrerade i dagens samhälle. Systemens komplexitet ökar och med det karven på hög kvalitet under utvecklingen. Detta blir en utmaning för de företag som utvecklar systemen. En lösning som är på uppgång för detta är användningen av simulering och virtuell driftsättning.  I denna rapport studeras processen för kvalitetskontroll och effektiv användning av simulering i utvecklingsprojekt av automationssystem. Fokus ligger på mjukvarudelen av systemen. Studien är gjord som en intervjustudie av personal från ett automationsutvecklings företag. Efter intervjuerna analyserades materialet och kombinerades med generella teorier om kvalitetskontroll och testning i mjukvaruutveckling. Processens tester kombinerades sedan med vad som krävs av en simulator för att utföra dessa. Resultatet av detta arbete är för det första en detaljerad bild av kvalitetskontrolls processen. Detta visar att systemen tests två gånger med samma testhierarki, först under utvecklingen och sedan under driftsättningen. Skillnaden är att under utvecklingen saknas den riktiga hårdvaran och process systemet vilket påverkar mjukvarans funktionalitet och begränsar testbarheten. Genom att använda simulering under utvecklingen kan skillnaden mellan systemen före och efter distribution vilket ökar kvaliteten. Överväganden gällande vilken nivå av simulering som behövs för att värdet av simulerings potentiella förmåga att ta bort fel skall bli göre en kostande för att utveckla simuleringen.
49

Anomaly Detection in the EtherCAT Network of a Power Station : Improving a Graph Convolutional Neural Network Framework

Barth, Niklas January 2023 (has links)
In this thesis, an anomaly detection framework is assessed and fine-tuned to detect and explain anomalies in a power station, where EtherCAT, an Industrial Control System, is employed for monitoring. The chosen framework is based on a previously published Graph Neural Network (GNN) model, utilizing attention mechanisms to capture complex relationships between diverse measurements within the EtherCAT system. To address the challenges in graph learning and improve model performance and computational efficiency, the study introduces a novel similarity thresholding approach. This approach dynamically selects the number of neighbors for each node based on their similarity instead of adhering to a fixed 'k' value, thus making the learning process more adaptive and efficient. Further in the exploration, the study integrates Extreme Value Theory (EVT) into the framework to set the anomaly detection threshold and assess its effectiveness. The effect of temporal features on model performance is examined, and the role of seconds of the day as a temporal feature is notably highlighted. These various methodological innovations aim to refine the application of the attention based GNN framework to the EtherCAT system. The results obtained in this study illustrate that the similarity thresholding approach significantly improves the model's F1 score compared to the standard TopK approach. The inclusion of seconds of the day as a temporal feature led to modest improvements in model performance, and the application of EVT as a thresholding technique was explored, although it did not yield significant benefits in this context. Despite the limitations, including the utilization of a single-day dataset for training, the thesis provides valuable insights for the detection of anomalies in EtherCAT systems, contributing both to the literature and the practitioners in the field. It lays the groundwork for future research in this domain, highlighting key areas for further exploration such as larger datasets, alternative anomaly detection techniques, and the application of the framework in streaming data environments. / I denna avhandling utvärderas och finslipas ett ramverk för att detektera och förklara anomalier på ett kraftverk, där EtherCAT, ett industriellt styrsystem, används för övervakning. Det valda ramverket är baserat på en tidigare publicerad graf neurala nätverksmodell (GNN) som använder uppmärksamhetsmekanismer för att fånga komplexa samband mellan olika mätningar inom EtherCAT-systemet. För att hantera utmaningar inom grafiskt lärande och förbättra modellens prestanda och beräkningseffektivitet introducerar studien en ny metod för likhetsgränsdragning. Denna metod väljer dynamiskt antalet grannar för varje nod baserat på deras likhet istället för att hålla sig till ett fast 'k'-värde, vilket gör inlärningsprocessen mer anpassningsbar och effektiv. I en vidare undersökning integrerar studien extremvärdesteori (EVT) i ramverket för att sätta tröskeln för detektering av anomalier och utvärdera dess effektivitet. Effekten av tidsberoende egenskaper på modellens prestanda undersöks, och sekunder av dagen som en tidsberoende egenskap framhävs särskilt. Dessa olika metodologiska innovationer syftar till att förädla användningen av det uppmärksamhetsbaserade GNN-ramverket på EtherCAT-systemet. Resultaten som erhållits i denna studie illustrerar att likhetsgränsdragning väsentligt förbättrar modellens F1-poäng jämfört med den standardiserade TopK-metoden. Inkluderingen av sekunder av dagen som en tidsberoende egenskap ledde till blygsamma förbättringar i modellens prestanda, och användningen av EVT som en tröskelmetod undersöktes, även om den inte gav några betydande fördelar i detta sammanhang. Trots begränsningarna, inklusive användningen av ett dataset för endast en dag för träning, ger avhandlingen värdefulla insikter för detektering av anomalier i EtherCAT-system, och bidrar både till litteraturen och praktiker inom området. Den lägger grunden för framtida forskning inom detta område, och belyser nyckelområden för ytterligare utforskning såsom större dataset, alternativa tekniker för detektering av anomalier och tillämpningen av ramverket i strömmande data-miljöer.
50

Diseño conceptual de un sistema automático para limpieza de ventanas en edificios de altura

Rubio Amoretti, Sergio Enrique 30 November 2020 (has links)
En este trabajo de investigación, se presenta el diseño conceptual de un sistema para limpieza de ventanas en edificios de altura. Esta propuesta nace con la idea de convertirse en una solución de bajo costo, para enfrentar la problemática sobre accidentes por caída en este tipo de actividades. Por ello, el objetivo general del presente trabajo es diseñar un sistema automático para la limpieza de ventanas sin perfiles en edificios altos, cuyo funcionamiento puede ser automático o controlado por un operario desde un dispositivo móvil. El concepto de solución óptimo está conformado por un robot, encargado de realizar la limpieza por medio de un cepillo giratorio que remueve el polvo y la suciedad gracias a una solución líquida que es asperjada sobre las ventanas; y un sistema de acceso a fachadas o BMU (Building Maintenance Unit) portátil, encargado tanto de sujetar al robot desde la parte superior del edificio, como de su desplazamiento. Finalmente, mediante esta investigación se ha logrado demostrar que es posible elaborar un equipo automático de bajo costo para la limpieza de ventanas en edificios de altura, ya que las tecnologías a emplearse presentan una disponibilidad amplia y son de uso común en el desarrollo de proyectos.

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