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An enhanced method in optimization rooted in direct collocation is formulated to treat the finite set optimal control problem. This is motivated by applications in which a hybrid dynamical system is subject to ordinary differential continuity constraints, but control variables are contained within finite spaces. Resulting solutions display control discontinuities as variables switch between one feasible value to another. Solutions derived are characterized as optimal switching schedules between feasible control values. The methodology allows control switches to be determined over a continuous spectrum, overcoming many of the limitations associated with discretized solutions. Implementation details are presented and several applications demonstrate the method’s utility and capability. Simple applications highlight the effectiveness of the methodology, while complicated dynamic systems showcase its relevance. A key example considers the challenges associated with libration point formations. Extensions are proposed for broader classes of hybrid systems. / text

Abstract Increasing efficiency is a necessary target for an industrial roaster nowadays. This thesis presents some studies on efficiency improvement in the zinc roasting process - process characterisation, control design, implementation and testing. The thesis focuses on the roaster, i.e. on research regarding the phenomena in the roaster furnace. By learning more about the roasting mechanism, particle size growth and dynamics of the furnace, new control implementations have been developed. More measurements, analyses and calculated variables have been added to give more information on the state of the furnace. New control variables have been introduced to give the operators more opportunities to set the conditions so that they are more suitable for the actual concentrate feed mixture. Equipment modifications have also been done. In this research, both laboratory and plant experiments have been performed together with thermodynamic evaluations and calculations. It has been necessary to make plant trials in order to obtain information about the impacts of different variables on the process. Only full-scale experiments give reliable results of the behaviour of an industrial furnace. The experiments with the roaster furnace have emphasised the study of both the metallurgy and the dynamics of the roasting process. The on-line calculated oxygen coefficient and its active control have proved important. The particle size distribution analysis of the furnace calcine has been shown to be a significant source of information for evaluating the state of the roasting furnace. The main target is to improve the economic performance. The key is to be able to be flexible in using different kinds of raw materials, because the main income is the treatment charge. The trend is that concentrates are becoming finer, which increases the challenges for roaster furnace control. The capability to use low-grade concentrates is also a major challenge and improves the economic result. Research and development on the boiler and mercury removal has also been part of this work for many reasons. Improved boiler performance and mercury removal gives more freedom in choosing concentrates and operating the roaster furnace. The approach has been the same as in the roaster furnace research and development work. Control improvements based on existing knowledge, such as fuzzy control systems for controlling the furnace temperature and mercury removal, did stabilize the process, but they did not solve all the problems regarding process stability. The research and development concept of this thesis has provided the extra knowledge needed for further improvement of process control. The results of the process characterisation have led to the implementation of a new and effective control strategy. The research and development carried out has improved performance in a number of ways: increased running time of the furnace and boiler, in-depth knowledge of roasting phenomena which led to new control methods and instructions for the operators, improved quality of sulphuric acid and a method to control its quality, measurements and analyses that give valuable information of the state of the process – all of which are now in use. In the future, the emphasis will be placed on the research and development of roaster furnace performance, which will be a great challenge. Control of the roaster furnace is the key to the economic success of the roasting process and more information about these phenomena is needed for improving and optimising control.

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International Telemetering Conference Proceedings / October 22-25, 1984 / Riviera Hotel, Las Vegas, Nevada / Software for real-time (time critical) control applications has been shown in military and industry studies to be a very expensive type of software effort. This type of software is not typically addressed in discussions of software architecture design methods and techniques, therefore the software engineer is usually left with a sparse design “tool kit” when confronted with overall system design involving time critical and/or control problems. This paper outlines the successful application of data flow and transaction analysis design methods to achieve a structured yet flexible software architecture for a fairly complex antenna controller used in automatic tracking antenna systems. Interesting adaptations of, and variations on, techniques described in the literature are discussed; as are issues of modularity, coupling, morphology, global data handling, and evolution (maintenance). Both positive and negative aspects of this choice of design method are outlined, and the importance of a capable real-time executive and conditional compilation and assembly is stressed.

New technological advances and the requirements to increasingly abide by new safety laws in engineering design projects highly affects industrial products in areas such as automotive, aerospace and railway industries. The necessity arises to design reduced-cost hi-tech products with minimal complexity, optimal performance, effective parameter robustness properties, and high reliability with fault tolerance. In this context the control system design plays an important role and the impact is crucial relative to the level of cost efficiency of a product. Measurement of required information for the operation of the design control system in any product is a vital issue, and in such cases a number of sensors can be available to select from in order to achieve the desired system properties. However, for a complex engineering system a manual procedure to select the best sensor set subject to the desired system properties can be very complicated, time consuming or even impossible to achieve. This is more evident in the case of large number of sensors and the requirement to comply with optimum performance. The thesis describes a comprehensive study of sensor selection for control and fault tolerance with the particular application of an ElectroMagnetic Levitation system (being an unstable, nonlinear, safety-critical system with non-trivial control performance requirements). The particular aim of the presented work is to identify effective sensor selection frameworks subject to given system properties for controlling (with a level of fault tolerance) the MagLev suspension system. A particular objective of the work is to identify the minimum possible sensors that can be used to cover multiple sensor faults, while maintaining optimum performance with the remaining sensors. The tools employed combine modern control strategies and multiobjective constraint optimisation (for tuning purposes) methods. An important part of the work is the design and construction of a 25kg MagLev suspension to be used for experimental verification of the proposed sensor selection frameworks.

Nonrigid image registration has received much attention in the medical imaging and computer vision research communities, because it enables a wide variety of applications. Feature tracking, segmentation, classification, temporal image differencing, tumour growth estimation, and pharmacokinetic modeling are examples of the many tasks that are enhanced by the use of aligned imagery. Over the years, the medical imaging and computer vision communties have developed and refined image registration techniques in parallel, often based on similar assumptions or underlying paradigms. This thesis focuses on variational registration, which comprises a subset of nonrigid image registration. It is divided into chapters that are based on fundamental aspects of the variational registration problem: image dissimilarity measures, changing overlap regions, regularizers, and computational solution strategies. Key contributions include the development of local versions of standard dissimilarity measures, the handling of changing overlap regions in a manner that is insensitive to the amount of non-interesting background information, the combination of two standard taxonomies of regularizers, and the generalization of solution techniques based on Fourier methods and the Demons algorithm for use with many regularizers. To illustrate and validate the various contributions, two sets of example imagery are used: 3D CT, MR, and PET images of the brain as well as 3D CT images of lung cancer patients.

Parental control applications were introduced to regulate and avoid the negative effects of adolescents’ technology usage. However, parental control apps lack focus on promoting adolescents' autonomy and parent-adolescent collaboration. Therefore, the aim of this paper is to research how parental control apps can be designed to support adolescents’ development towards adulthood and to enhance the active participation from both parties. The research was conducted by interviewing parents (N=7) in which a provocative prototype was used to prime discussions around the topic. This study generated five design implications which are parent-adolescent collaboration, communication support for parental understanding, communication support customized for different cultures, incentivizing healthier habits, and adapting the design for different literacy levels. These implications were extracted from the results which show that parents respect their adolescent’s digital privacy and autonomy. However, there are indications that although parents value insight into their adolescent’s online activities, they are concerned about the infringement of their privacy. Our results suggest that parent-adolescent collaboration is essential for meeting the requirements of parents and adolescents. We conclude that parental control apps could be designed in alternative ways with less focus on surveillance functionality and instead strive for aspects of collaboration, communication, and autonomy.

Este trabalho propõe investigar, desenvolver e validar uma metodologia de projeto para sistemas de diagnóstico para detecção de falhas e anomalias em aplicações de acionamento de motores elétricos, comumente utilizados na indústria de manufatura. A metodologia proposta é baseada na coleta e interpretação de dados de processo de redes PROFINET, perfil PROFIdrive, e ferramentas de aprendizagem de máquinas. Técnicas de extração e redução de atributos são aplicadas nos dados de processo coletados. Estes atributos são utilizados em algoritmos para reconhecimento de padrões, os algoritmos investigados são o k-Nearest Neighbor, Redes Neurais Artificiais, Support Vector Machines, e adicionalmente uma adaptação da metodologia é feita utilizando um algoritmo para detecção de novidades. A avaliação da metodologia considerou quatro cenários para estudos de caso, para falhas comuns em aplicações de máquinas rotativas. Os resultados alcançados demonstram a eficácia da metodologia, que foi capaz de detectar as falhas e anomalias investigadas de maneira satisfatória, similares a trabalhos correlatos, com o diferencial de não exigirem sensores adicionais dedicados na coleta de dados. Desta maneira, o trabalho contribui para área de redes de comunicação industrial, mais especificamente o protocolo PROFINET, diagnósticos de anomalias em máquinas acionadas por motores elétricos, e ferramentas de aprendizagem de máquinas. / This work proposes to investigate, develop and validate a methodology to design diagnostic systems to detect faults and anomalies in motion control applications, commonly used in manufacturing industry. The proposed methodology is based on collection and interpretation of process data from PROFINET networks, PROFIdrive profile, and machine learning tools. Feature extraction and selection techniques are applied to the collected process data. These features are used in algorithms for pattern recognition problems. Investigated algorithms are k-Nearest Neighbor, Artificial Neural Networks, Support Vector Machines and in addition, an adaptation of the methodology is held for novelty detection. Four scenarios were considered as case of studies for methodology evaluation, based on common faults in rotating machine applications. The results proved the methodology effectiveness for diagnostic system design, which were able to detect satisfactorily the investigated faults and anomalies, similar to related work, with the differential of not requiring additional dedicated sensors for data collection. In this way, the work contributes to the area of industrial communication networks, more specifically in PROFINET protocol, diagnostic systems for fault detection in motion control applications, and machine learning tools.

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.