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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.
21

Diagnóstico da camada física de redes Profibus DP baseado em redes neurais artificiais / Physical diagnostic for Profibus DP networks based on artificial neural networks

Souza, Rafaela Castelhano de 12 April 2012 (has links)
A rede PROFIBUS DP é o barramento de campo mais utilizado na indústria mundial atualmente. Com o uso cada vez maior desta rede de \"chão de fábrica\" nas plantas industriais, o diagnóstico rápido de falhas tornou-se extremamente necessário e importante, o que permite minimizar os tempos de parada da instalação e consequentes prejuízos no processo produtivo. Este trabalho apresenta o estudo de técnicas baseadas em Redes Neurais Artificiais (RNA) que serão utilizadas em um trabalho futuro para se fazer um diagnóstico rápido de uma rede PROFIBUS em caso de falha, permitindo através dos conceitos básicos apresentados, uma análise criteriosa do seu desempenho. Inicialmente são apresentados conceitos básicos sobre as redes PROFIBUS DP, tais como arquitetura e versões do protocolo, a descrição da Camada Física, dentre outros assuntos relevantes. Nas etapas seguintes, serão apresentados outros tópicos importantes para entendimento do projeto como, conceitos sobre RNA e métodos de pré-processamento do sinal colhido no osciloscópio. / The PROFIBUS (Process Field Bus) DP is the most popular fieldbus communication used in the worldwide industry. With the increasing use of this network fieldbus in industrial plants, the rapid faults diagnosis has become extremely necessary and important, which minimizes the lodgments time and consequent losses in the production process. This work is based into a Artificial Neural Networks (ANN) tool that will be used to make a rapidly diagnosis of a PROFIBUS network in case of failure, allowing through basic concepts, a careful review of their performance. First the basics of PROFIBUS DP networks are presented, such as architecture and protocol versions, a description of the Physical Layer, among other relevant issues. In the following steps, others important topics to understand the project will be shown, such as, concepts of ANN and pre-processing methods from collected signal.
22

Diagnóstico da camada física de redes Profibus DP baseado em redes neurais artificiais / Physical diagnostic for Profibus DP networks based on artificial neural networks

Rafaela Castelhano de Souza 12 April 2012 (has links)
A rede PROFIBUS DP é o barramento de campo mais utilizado na indústria mundial atualmente. Com o uso cada vez maior desta rede de \"chão de fábrica\" nas plantas industriais, o diagnóstico rápido de falhas tornou-se extremamente necessário e importante, o que permite minimizar os tempos de parada da instalação e consequentes prejuízos no processo produtivo. Este trabalho apresenta o estudo de técnicas baseadas em Redes Neurais Artificiais (RNA) que serão utilizadas em um trabalho futuro para se fazer um diagnóstico rápido de uma rede PROFIBUS em caso de falha, permitindo através dos conceitos básicos apresentados, uma análise criteriosa do seu desempenho. Inicialmente são apresentados conceitos básicos sobre as redes PROFIBUS DP, tais como arquitetura e versões do protocolo, a descrição da Camada Física, dentre outros assuntos relevantes. Nas etapas seguintes, serão apresentados outros tópicos importantes para entendimento do projeto como, conceitos sobre RNA e métodos de pré-processamento do sinal colhido no osciloscópio. / The PROFIBUS (Process Field Bus) DP is the most popular fieldbus communication used in the worldwide industry. With the increasing use of this network fieldbus in industrial plants, the rapid faults diagnosis has become extremely necessary and important, which minimizes the lodgments time and consequent losses in the production process. This work is based into a Artificial Neural Networks (ANN) tool that will be used to make a rapidly diagnosis of a PROFIBUS network in case of failure, allowing through basic concepts, a careful review of their performance. First the basics of PROFIBUS DP networks are presented, such as architecture and protocol versions, a description of the Physical Layer, among other relevant issues. In the following steps, others important topics to understand the project will be shown, such as, concepts of ANN and pre-processing methods from collected signal.
23

Diagnóstico automático de redes Profibus / Automatic diagnosis for Profibus networks

Eduardo André Mossin 19 September 2012 (has links)
Esta tese propõe a utilização de sistemas inteligentes para, automaticamente, realizar diagnósticos e localizar falhas na instalação e na operação de redes de comunicação industrial que utilizam o protocolo Profibus DP. Para tais tarefas, uma série de análises é realizada a partir dos sinais transmitidos pela camada física, de telegramas transmitidos pela camada de enlace e de funções da camada de usuário do protocolo Profibus DP. Para a análise da camada física, amostras dos sinais elétricos transmitidos são processadas e apresentadas a algumas Redes Neurais Artificiais para que sejam classificadas de acordo com a sua forma de onda. Caso estes sinais apresentem alguma deformação, o sistema indica uma provável causa para o problema, afinal, os problemas das redes Profibus originam padrões específicos e característicos impressos nas formas de onda do sinal digital. Ainda através da análise das amostras dos sinais oriundos da camada física, algumas fontes de problemas são detectadas a partir da análise do nível médio de tensão do sinal que um determinado dispositivo está transmitindo. Tal análise é realizada a partir de um Sistema Especialista. Também utilizando Sistemas Especialistas, os telegramas transmitidos pela camada de enlace deste protocolo são analisados e a partir destes, falhas de configuração são detectadas. Por fim, é proposto um sistema nebuloso responsável por indicar ao usuário um valor próximo ao ideal para a variável de tempo denominada target rotation time. A proposta foi testada e validada a partir de dados obtidos de redes Profibus estabelecidas em laboratório e de alguns dados sintéticos originados por software. Os resultados obtidos foram suficientes para a comprovação da tese de que sistemas computacionais inteligentes podem contribuir de maneira efetiva no diagnóstico de problemas em redes Profibus DP e até mesmo em outros tipos de rede. / This thesis proposes the use of intelligent systems to automatically perform diagnostics and locate faults during the installation and operation of industrial communication networks that use the Profibus DP protocol. For such tasks, some analyzes are performed from the signals transmitted by the physical layer, from telegrams transmitted by the data link layer and from some user layer functions of the Profibus DP protocol. For physical layer analysis, the transmitted electrical signals samples are processed and submitted for some artificial neural networks that classifies each signal according to its waveshape. If these signals have some deformation, the system indicates a probable cause for the problem, after all, the Profibus problems originate specific and characteristic patterns printed on the digital signal waveform. Still analyzing the physical layer signal samples, some problems sources are detected from the signal voltage analysis. Such analysis is performed from an Expert System. Also using expert systems, the data link layer telegrams are analyzed and configuration faults are detected. Finally, it is proposed a fuzzy system responsible for specify a value close to ideal for the target rotation time variable. The proposal has been tested and validated with data from Profibus networks established in laboratory. Besides, some synthetic data were generated by software. The results were sufficient to prove the thesis that intelligent computational systems can contribute effectively to diagnose problems in Profibus DP networks and even in other types of networks.
24

Gerenciamento de ativos aplicado a instrumentos de campo de protocolos abertos: uma abordagem a partir de dispositivos móveis / Asset management tools applied to the field of open protocols: an approach from mobile devices.

Carrijo, Renato Santos 31 January 2012 (has links)
A tecnologia emergente dos dispositivos móveis como telefones celulares, handhelds e smartphones trouxe um novo paradigma para o uso desses equipamentos, que, além das convencionais chamadas de áudio, hoje suportam vídeo, internet e redes sem fio. Várias aplicações têm sido desenvolvidas para esse ambiente. Por outro lado, na área da automação industrial, os instrumentos de campo modernos contêm embutidos, internamente, conjuntos de informações que proporcionam grande oportunidade para a gestão de ativos. A necessidade do gerenciamento de ativos ocorre na fase de operação da planta industrial e é realizada por meio de ajustes finos, calibrações, alteração de configurações e manutenções, com o objetivo de se evitar paradas indesejadas. Esse trabalho insere-se no contexto de interface entre esses dois mundos: a computação móvel e o gerenciamento de ativos. Nesse sentido, é desenvolvida uma análise dos padrões abertos PROFIBUS PA, HART e Foundation Fieldbus e o uso das suas características aplicado ao gerenciamento de ativos. É apresentada, ainda, uma proposta e verificação de viabilidade técnica de uma arquitetura aplicada ao gerenciamento de ativos a partir de um dispositivo móvel usando-se um canal de comunicação seguro baseado no padrão CyberOPC para acesso à planta industrial / The emerging technology of mobile devices like cell phones, hand helds and smartphones has brought a new paradigm for the use of such equipment, witch, in addition to conventional audio calls, now supports video, internet and wireless networks. Several applications have been developed for this environment. On the other hand, in the industrial automation area, the modern field devices contain embedded information sets that provide great opportunity for asset management. The need for asset management occurs during the operation of the plant and is performed by means of fine tuning, calibration, changes of configuration and maintenance, in order to avoid undesired downtime. This work fits into the context of interface between these two worlds: mobile computing and asset management. In this sense, is made an analysis of open standards PROFIBUS PA, HART and Foundation Fieldbus and use its features applied to asset management. It also presented a proposal and verification of technical feasibility of an architecture applied to asset management from a mobile device using a secure communication channel based on the standard CyberOPC to access the industrial plant
25

Σχεδιασμός και υλοποίηση συστήματος αυτοματισμού συγκροτήματος φαρίνας ΠΚ4 και ΠΚ5 με χρήση PLC, ανάπτυξη μιμητικών διαγραμμάτων (SCADA) και αντικατάσταση ηλεκτρολογικών διανομών στο εργοστάσιο «Όλυμπος» της ΑΓΕΤ Ηρακλής

Ανέστης, Κυριάκος 16 June 2011 (has links)
Η παρακάτω διπλωματική εργασία περιλαμβάνει την περιγραφή των εργασιών που πραγματοποιήθηκαν κατά τον εκσυγχρονισμό του συστήματος αυτοματισμού των σιλό φαρίνας Δ και Ε. Αρχικά περιγράφεται περιληπτικά η διαδικασία παραγωγής του τσιμέντου και ο ρόλος των σιλό φαρίνας Δ και Ε στη γραμμή παραγωγής. Στη συνέχεια αναλύεται η μετάβαση από τον κλασσικό αυτοματισμό στη χρήση Προγραμματιζόμενου Λογικού Ελεγκτή (PLC) και αναφέρονται οι σημαντικότερες αλλαγές που συνέβησαν. Το επόμενο κομμάτι της εργασίας αναφέρεται στο διάγραμμα ροής του συγκροτήματος φαρίνας ΠΚ4 και ΠΚ5 όπου παρατίθεται σχετικό σχεδιάγραμμα με τη ροή του υλικού ενώ επιπροσθέτως περιγράφεται η λειτουργία όλων των μηχανών που περιλαμβάνονται σ’ αυτό. Έπειτα γίνεται μετάβαση στη λογική αυτοματισμού που αναπτύχθηκε από τους μηχανικούς αυτοματισμού του εργοστασίου όπου περιγράφονται όλες οι είσοδοι και οι έξοδοι του PLC, το πρόγραμμα που χρησιμοποιήθηκε και ο κώδικας προγράμματος που δημιουργήθηκε. Αμέσως μετά γίνεται ξεχωριστή αναφορά στο μιμητικό διάγραμμα (SCADA) με παράθεση των εικόνων που το αποτελούν και επεξήγηση όλων των ενδείξεων και επιλογών που περιλαμβάνει. Στη συνέχεια αναφέρονται τα δίκτυα που χρησιμοποιήθηκαν για τον έλεγχο της μονάδας των σιλό Δ και Ε, δηλαδή το βιομηχανικό δίκτυο Profibus και το δίκτυο Ethernet, όπου περιγράφεται ο τρόπος επικοινωνίας των χειριστών της μονάδας με τις μηχανές της διεργασίας. Το τελευταίο τμήμα της εργασίας περιλαμβάνει την βήμα προς βήμα περιγραφή των εργασιών ως την ολοκλήρωση του έργου, τη διαδικασία του τελικού ελέγχου του έργου καθώς και μια σύντομη αναφορά στη συμμετοχή του φοιτητή σε τμήμα των παραπάνω εργασιών. Η διπλωματική εργασία κλείνει με την παράθεση των πηγών καθώς και ορισμένων συμπληρωματικών παραρτημάτων. / The following thesis includes a description of the work carried out during the modernization of the automation system of raw meal silo D and E. Firstly it is described briefly the production process of cement and the role of raw meal silo D and E on the production line. Afterwards the transition from classical automation to the use of a Programmable Logic Controller (PLC) and some of the most significant changes occurred are analyzed. In the next chapter it is reported the complex flow of raw meal PK4 and PK5 citing a diagram with the flow of material and furthermore the operation of all machinery therein is described. Following there is a shift in the automation logic developed by automation engineers of the factory describing all inputs and outputs of the PLC, the program used and the program code created. A separate reference to mimetic diagram (SCADA) follows including the images that constitute it and an explanation of all the indications and options included. The next chapter includes the networks used for the control unit of the silo D and E, which are the Profibus industrial network and the network Ethernet, where it is described the way in which the operator of the plant contacts with the machinery of the process. The last part of the thesis includes step-by-step the description of the works as the project is completed, the process of final verification of the project and a brief reference to the student’s involvement. The thesis concludes with a statement of sources and some additional annexes.
26

Gerenciamento de ativos aplicado a instrumentos de campo de protocolos abertos: uma abordagem a partir de dispositivos móveis / Asset management tools applied to the field of open protocols: an approach from mobile devices.

Renato Santos Carrijo 31 January 2012 (has links)
A tecnologia emergente dos dispositivos móveis como telefones celulares, handhelds e smartphones trouxe um novo paradigma para o uso desses equipamentos, que, além das convencionais chamadas de áudio, hoje suportam vídeo, internet e redes sem fio. Várias aplicações têm sido desenvolvidas para esse ambiente. Por outro lado, na área da automação industrial, os instrumentos de campo modernos contêm embutidos, internamente, conjuntos de informações que proporcionam grande oportunidade para a gestão de ativos. A necessidade do gerenciamento de ativos ocorre na fase de operação da planta industrial e é realizada por meio de ajustes finos, calibrações, alteração de configurações e manutenções, com o objetivo de se evitar paradas indesejadas. Esse trabalho insere-se no contexto de interface entre esses dois mundos: a computação móvel e o gerenciamento de ativos. Nesse sentido, é desenvolvida uma análise dos padrões abertos PROFIBUS PA, HART e Foundation Fieldbus e o uso das suas características aplicado ao gerenciamento de ativos. É apresentada, ainda, uma proposta e verificação de viabilidade técnica de uma arquitetura aplicada ao gerenciamento de ativos a partir de um dispositivo móvel usando-se um canal de comunicação seguro baseado no padrão CyberOPC para acesso à planta industrial / The emerging technology of mobile devices like cell phones, hand helds and smartphones has brought a new paradigm for the use of such equipment, witch, in addition to conventional audio calls, now supports video, internet and wireless networks. Several applications have been developed for this environment. On the other hand, in the industrial automation area, the modern field devices contain embedded information sets that provide great opportunity for asset management. The need for asset management occurs during the operation of the plant and is performed by means of fine tuning, calibration, changes of configuration and maintenance, in order to avoid undesired downtime. This work fits into the context of interface between these two worlds: mobile computing and asset management. In this sense, is made an analysis of open standards PROFIBUS PA, HART and Foundation Fieldbus and use its features applied to asset management. It also presented a proposal and verification of technical feasibility of an architecture applied to asset management from a mobile device using a secure communication channel based on the standard CyberOPC to access the industrial plant
27

Reducera stopptiden för en lutanalysator : Kan detta göras med ett användarvänligt gränssnitt?

Johansson, David January 2021 (has links)
The Smurfit Kappa Piteå is Europe's largest paper mill for Kraftliner. [1] The factory contains of both a sulphate mill and a paper mill including two paper machines. In a sulphate mill, pulp is produced by boiling wood chips with liquor that contains active chemicals such as Na2S and NaOH. There is a cost saving in chemical recycling instead of replacing used chemicals with new ones. In order for boiling pulp and have the process of recycling of chemicals to work optimally, the various liquids must maintain certain values and concentrations. It takes a lot of time and resources when the operators have to do it manually, and therefore the process owner has invested in a process analyzer that is physically connected to the pipes where the chemicals pass to automatically take out samples and analyze them. However, the analyzer has very big problems with crystallization of transportation pipes, valves that get stuck, and the only unit that provides information about the problems is a HMI-display located next to the factory's soda boiler. This place next to the soda boiler is an unpleasant area to stay at. That is one of the reasons that it often takes a long time from the analyzer encounters a problem until someone discovers the problem and contacts the accurate service department to fix the problem. The availability of the analyzer thus needs to be developed. The analyzer had its own PLC with control signals for valves and sensors. Those signals were picked out and sent through a PROFIbus DP to the operators ordinary control system ABB 800Xa. Also, a process image of the analyzer was designed and a number of functions for detecting and reporting problems were implemented. Each valve and sensor received its own faceplate with associated alarms. Now the operators could, with this user-friendly system, more quickly detect problems and address them to the right maintenance department. By interviewing the operators who work with the analyzer, it was made possible to measure the use of creating a new process image as a tool for troubleshooting. Many operators say in the interviews that they feel that the new process image makes them more aware of operational malfunctions of the analyzer that require action. However, some of the mechanical weaknesses in the design that cause these problems still remains, and must be fixed. / Smurfit Kappa Piteå är Europas största pappersbruk för Kraftliner. [1] De har både ett sulfatbruk och ett pappersbruk med två egna pappersmaskiner. I ett sulfatbruk tillverkas pappersmassa genom att koka träflis med vitlut som innehåller aktiva kokkemikalier såsom Na2S och NaOH. Det finns en kostnadsbesparing i kemikalieåtervinning istället för att ersätta förbrukade kokkemikalier. För att kokning av pappersmassa och återvinning av kemikalier ska fungera optimalt måste de olika vätskorna hålla vissa styrkor och koncentrationer. Det kostar tid och resurser när operatörerna gör det manuellt, därför har processägaren investerat i en processanalysator som är fysiskt ansluten till de ledningar där de viktiga kemikalierna transporteras för att automatiskt ta ut prov och analysera dessa. Analysatorn har dock problem med kristallisering av ledningar, ventiler som fastnar samtidigt som den tillhörande HMI-displayen ger knapphändig information om problemen. Därtill är HMI-displayen placerad i anslutning till fabrikens sodalutpanna, och är besvärlig att komma åt. Det tar ofta lång tid från det att analysatorn stöter på problem tills dess att någon upptäckt det, samt adresserat rätt avdelning för att avhjälpa felet. Tillgängligheten för analysatorn behövde förbättras. Analysatorns styrsignaler för dess ventiler och sensorer plockades ut och skickades via en PROFIbus DP till operatörernas ordinarie styrsystem. Därefter designades en processbild som visualiserade hur analysatorn ser ut, och ett antal funktioner för att upptäcka och rapportera problem implementerades. Varje ventil och sensor fick sin egen faceplate med tillhörande larm. Detta för att möjliggöra att operatörerna med ett användarvänligt system, snabbare upptäcka problem och adressera dem till rätt underhållsavdelning. Genom att intervjua operatörer som jobbar på det processavsnitt där analysatorn står placerad kan det konstateras att målet att designa en ny processbild, samt använda den och dess funktioner som ett verktyg för att snabbare upptäcka och adressera problem fungerar. Många operatörer säger i intervjuerna att de upplever att den nya processbilden gör dem mer uppmärksamma på driftstörningar av analysatorn som kräver åtgärder. Däremot så kvarstår en del av de mekaniska svagheter i konstruktionen som orsakar dessa problem.
28

Development of a Bioreactor Simulator for supporting automation software test and verification

Liljequist, Viktor January 2017 (has links)
The GE Healthcare Life sciences organization develop and manufacture bioreactors, mixers, filtration skids and chromatography systems used together in a biomanufacturing platform. The platform is monitored and controlled by a distributed control system through a Programmable Logic Controller (PLC). The automation software controlling the platform is today tested and verified together with the physical units. The software use PROFIBUS, an industry standard for industrial automation, for communication and control of the units. Limited access to the physical units is usually a bottleneck and it's difficult to test abnormal situations to make sure the correct alarms are triggered. To reduce the hardware dependency and to provide support during test and verification, a virtual environment is developed to simulate the behavior of a bioreactor during execution. A .NET application has been developed together with a mathematical framework to simulate a cell culture and to return relevant process parameters such as pH, dissolved oxygen, temperature and weight. The results show that it's possible to simulate a bioreactor and to communicate with the control system. The software can be a valuable tool when developing and testing automation software but should not be used for process optimization or tuning of control parameters.
29

Förstudie : n+D821ytt kranlager för hjulmontering på Exel

Pettersson, Erik January 2005 (has links)
No description available.
30

Förstudie : n+D821ytt kranlager för hjulmontering på Exel

Pettersson, Erik January 2005 (has links)
No description available.

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