133 research outputs found

    Engineering framework for service-oriented automation systems

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    Tese de doutoramento. Engenharia InformĂĄtica. Universidade do Porto. Faculdade de Engenharia. 201

    The DS-Pnet modeling formalism for cyber-physical system development

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    This work presents the DS-Pnet modeling formalism (Dataflow, Signals and Petri nets), designed for the development of cyber-physical systems, combining the characteristics of Petri nets and dataflows to support the modeling of mixed systems containing both reactive parts and data processing operations. Inheriting the features of the parent IOPT Petri net class, including an external interface composed of input and output signals and events, the addition of dataflow operations brings enhanced modeling capabilities to specify mathematical data transformations and graphically express the dependencies between signals. Data-centric systems, that do not require reactive controllers, are designed using pure dataflow models. Component based model composition enables reusing existing components, create libraries of previously tested components and hierarchically decompose complex systems into smaller sub-systems. A precise execution semantics was defined, considering the relationship between dataflow and Petri net nodes, providing an abstraction to define the interface between reactive controllers and input and output signals, including analog sensors and actuators. The new formalism is supported by the IOPT-Flow Web based tool framework, offering tools to design and edit models, simulate model execution on the Web browser, plus model-checking and software/hardware automatic code generation tools to implement controllers running on embedded devices (C,VHDL and JavaScript). A new communication protocol was created to permit the automatic implementation of distributed cyber-physical systems composed of networks of remote components communicating over the Internet. The editor tool connects directly to remote embedded devices running DS-Pnet models and may import remote components into new models, contributing to simplify the creation of distributed cyber-physical applications, where the communication between distributed components is specified just by drawing arcs. Several application examples were designed to validate the proposed formalism and the associated framework, ranging from hardware solutions, industrial applications to distributed software applications

    Computing multi-scale organizations built through assembly

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    The ability to generate and control assembling structures built over many orders of magnitude is an unsolved challenge of engineering and science. Many of the presumed transformational benefits of nanotechnology and robotics are based directly on this capability. There are still significant theoretical difficulties associated with building such systems, though technology is rapidly ensuring that the tools needed are becoming available in chemical, electronic, and robotic domains. In this thesis a simulated, general-purpose computational prototype is developed which is capable of unlimited assembly and controlled by external input, as well as an additional prototype which, in structures, can emulate any other computing device. These devices are entirely finite-state and distributed in operation. Because of these properties and the unique ability to form unlimited size structures of unlimited computational power, the prototypes represent a novel and useful blueprint on which to base scalable assembly in other domains. A new assembling model of Computational Organization and Regulation over Assembly Levels (CORAL) is also introduced, providing the necessary framework for this investigation. The strict constraints of the CORAL model allow only an assembling unit of a single type, distributed control, and ensure that units cannot be reprogrammed - all reprogramming is done via assembly. Multiple units are instead structured into aggregate computational devices using a procedural or developmental approach. Well-defined comparison of computational power between levels of organization is ensured by the structure of the model. By eliminating ambiguity, the CORAL model provides a pragmatic answer to open questions regarding a framework for hierarchical organization. Finally, a comparison between the designed prototypes and units evolved using evolutionary algorithms is presented as a platform for further research into novel scalable assembly. Evolved units are capable of recursive pairing ability under the control of a signal, a primitive form of unlimited assembly, and do so via symmetry-breaking operations at each step. Heuristic evidence for a required minimal threshold of complexity is provided by the results, and challenges and limitations of the approach are identified for future evolutionary studies

    Industrial Applications: New Solutions for the New Era

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    This book reprints articles from the Special Issue "Industrial Applications: New Solutions for the New Age" published online in the open-access journal Machines (ISSN 2075-1702). This book consists of twelve published articles. This special edition belongs to the "Mechatronic and Intelligent Machines" section

    Methoden und Beschreibungssprachen zur Modellierung und Verifikation vonSchaltungen und Systemen: MBMV 2015 - Tagungsband, Chemnitz, 03. - 04. MĂ€rz 2015

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    Der Workshop Methoden und Beschreibungssprachen zur Modellierung und Verifikation von Schaltungen und Systemen (MBMV 2015) findet nun schon zum 18. mal statt. Ausrichter sind in diesem Jahr die Professur Schaltkreis- und Systementwurf der Technischen UniversitĂ€t Chemnitz und das Steinbeis-Forschungszentrum Systementwurf und Test. Der Workshop hat es sich zum Ziel gesetzt, neueste Trends, Ergebnisse und aktuelle Probleme auf dem Gebiet der Methoden zur Modellierung und Verifikation sowie der Beschreibungssprachen digitaler, analoger und Mixed-Signal-Schaltungen zu diskutieren. Er soll somit ein Forum zum Ideenaustausch sein. Weiterhin bietet der Workshop eine Plattform fĂŒr den Austausch zwischen Forschung und Industrie sowie zur Pflege bestehender und zur KnĂŒpfung neuer Kontakte. Jungen Wissenschaftlern erlaubt er, ihre Ideen und AnsĂ€tze einem breiten Publikum aus Wissenschaft und Wirtschaft zu prĂ€sentieren und im Rahmen der Veranstaltung auch fundiert zu diskutieren. Sein langjĂ€hriges Bestehen hat ihn zu einer festen GrĂ¶ĂŸe in vielen Veranstaltungskalendern gemacht. Traditionell sind auch die Treffen der ITGFachgruppen an den Workshop angegliedert. In diesem Jahr nutzen zwei im Rahmen der InnoProfile-Transfer-Initiative durch das Bundesministerium fĂŒr Bildung und Forschung geförderte Projekte den Workshop, um in zwei eigenen Tracks ihre Forschungsergebnisse einem breiten Publikum zu prĂ€sentieren. Vertreter der Projekte Generische Plattform fĂŒr SystemzuverlĂ€ssigkeit und Verifikation (GPZV) und GINKO - Generische Infrastruktur zur nahtlosen energetischen Kopplung von Elektrofahrzeugen stellen Teile ihrer gegenwĂ€rtigen Arbeiten vor. Dies bereichert denWorkshop durch zusĂ€tzliche Themenschwerpunkte und bietet eine wertvolle ErgĂ€nzung zu den BeitrĂ€gen der Autoren. [... aus dem Vorwort

    Third CLIPS Conference Proceedings, volume 1

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    Expert systems are computed programs which emulate human expertise in well defined problem domains. The potential payoff from expert systems is high: valuable expertise can be captured and preserved, repetitive and/or mundane tasks requiring human expertise can be automated, and uniformity can be applied in decision making processes. The C Language Integrated Production Systems (CLIPS) is an expert system building tool, developed at the Johnson Space Center, which provides a complete environment for the development and delivery of rule and/or object based expert systems. CLIPS was specifically designed to provide a low cost option for developing and deploying expert system applications across a wide range of hardware platforms. The development of CLIPS has helped to improve the ability to deliver expert systems technology throughout the public and private sectors for a wide range of applications and diverse computing environments

    Fifth Conference on Artificial Intelligence for Space Applications

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    The Fifth Conference on Artificial Intelligence for Space Applications brings together diverse technical and scientific work in order to help those who employ AI methods in space applications to identify common goals and to address issues of general interest in the AI community. Topics include the following: automation for Space Station; intelligent control, testing, and fault diagnosis; robotics and vision; planning and scheduling; simulation, modeling, and tutoring; development tools and automatic programming; knowledge representation and acquisition; and knowledge base/data base integration

    Algorithmic composition of music in real-time with soft constraints

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    Music has been the subject of formal approaches for a long time, ranging from Pythagoras’ elementary research on tonal systems to J. S. Bach’s elaborate formal composition techniques. Especially in the 20th century, much music was composed based on formal techniques: Algorithmic approaches for composing music were developed by composers like A. Schoenberg as well as in the scientific area. So far, a variety of mathematical techniques have been employed for composing music, e.g. probability models, artificial neural networks or constraint-based reasoning. In the recent time, interactive music systems have become popular: existing songs can be replayed with musical video games and original music can be interactively composed with easy-to-use applications running e.g. on mobile devices. However, applications which algorithmically generate music in real-time based on user interaction are mostly experimental and limited in either interactivity or musicality. There are many enjoyable applications but there are also many opportunities for improvements and novel approaches. The goal of this work is to provide a general and systematic approach for specifying and implementing interactive music systems. We introduce an algebraic framework for interactively composing music in real-time with a reasoning-technique called ‘soft constraints’: this technique allows modeling and solving a large range of problems and is suited particularly well for problems with soft and concurrent optimization goals. Our framework is based on well-known theories for music and soft constraints and allows specifying interactive music systems by declaratively defining ‘how the music should sound’ with respect to both user interaction and musical rules. Based on this core framework, we introduce an approach for interactively generating music similar to existing melodic material. With this approach, musical rules can be defined by playing notes (instead of writing code) in order to make interactively generated melodies comply with a certain musical style. We introduce an implementation of the algebraic framework in .NET and present several concrete applications: ‘The Planets’ is an application controlled by a table-based tangible interface where music can be interactively composed by arranging planet constellations. ‘Fluxus’ is an application geared towards musicians which allows training melodic material that can be used to define musical styles for applications geared towards non-musicians. Based on musical styles trained by the Fluxus sequencer, we introduce a general approach for transforming spatial movements to music and present two concrete applications: the first one is controlled by a touch display, the second one by a motion tracking system. At last, we investigate how interactive music systems can be used in the area of pervasive advertising in general and how our approach can be used to realize ‘interactive advertising jingles’.Musik ist seit langem Gegenstand formaler Untersuchungen, von Phytagoras‘ grundlegender Forschung zu tonalen Systemen bis hin zu J. S. Bachs aufwĂ€ndigen formalen Kompositionstechniken. Vor allem im 20. Jahrhundert wurde vielfach Musik nach formalen Methoden komponiert: Algorithmische AnsĂ€tze zur Komposition von Musik wurden sowohl von Komponisten wie A. Schoenberg als auch im wissenschaftlichem Bereich entwickelt. Bislang wurde eine Vielzahl von mathematischen Methoden zur Komposition von Musik verwendet, z.B. statistische Modelle, kĂŒnstliche neuronale Netze oder Constraint-Probleme. In der letzten Zeit sind interaktive Musiksysteme populĂ€r geworden: Bekannte Songs können mit Musikspielen nachgespielt werden, und mit einfach zu bedienenden Anwendungen kann man neue Musik interaktiv komponieren (z.B. auf mobilen GerĂ€ten). Allerdings sind die meisten Anwendungen, die basierend auf Benutzerinteraktion in Echtzeit algorithmisch Musik generieren, eher experimentell und in InteraktivitĂ€t oder MusikalitĂ€t limitiert. Es gibt viele unterhaltsame Anwendungen, aber ebenso viele Möglichkeiten fĂŒr Verbesserungen und neue AnsĂ€tze. Das Ziel dieser Arbeit ist es, einen allgemeinen und systematischen Ansatz zur Spezifikation und Implementierung von interaktiven Musiksystemen zu entwickeln. Wir stellen ein algebraisches Framework zur interaktiven Komposition von Musik in Echtzeit vor welches auf sog. ‚Soft Constraints‘ basiert, einer Methode aus dem Bereich der kĂŒnstlichen Intelligenz. Mit dieser Methode ist es möglich, eine große Anzahl von Problemen zu modellieren und zu lösen. Sie ist besonders gut geeignet fĂŒr Probleme mit unklaren und widersprĂŒchlichen Optimierungszielen. Unser Framework basiert auf gut erforschten Theorien zu Musik und Soft Constraints und ermöglicht es, interaktive Musiksysteme zu spezifizieren, indem man deklarativ angibt, ‚wie sich die Musik anhören soll‘ in Bezug auf sowohl Benutzerinteraktion als auch musikalische Regeln. Basierend auf diesem Framework stellen wir einen neuen Ansatz vor, um interaktiv Musik zu generieren, die Ă€hnlich zu existierendem melodischen Material ist. Dieser Ansatz ermöglicht es, durch das Spielen von Noten (nicht durch das Schreiben von Programmcode) musikalische Regeln zu definieren, nach denen interaktiv generierte Melodien an einen bestimmten Musikstil angepasst werden. Wir prĂ€sentieren eine Implementierung des algebraischen Frameworks in .NET sowie mehrere konkrete Anwendungen: ‚The Planets‘ ist eine Anwendung fĂŒr einen interaktiven Tisch mit der man Musik komponieren kann, indem man Planetenkonstellationen arrangiert. ‚Fluxus‘ ist eine Anwendung, die sich an Musiker richtet. Sie erlaubt es, melodisches Material zu trainieren, das wiederum als Musikstil in Anwendungen benutzt werden kann, die sich an Nicht-Musiker richten. Basierend auf diesen trainierten Musikstilen stellen wir einen generellen Ansatz vor, um rĂ€umliche Bewegungen in Musik umzusetzen und zwei konkrete Anwendungen basierend auf einem Touch-Display bzw. einem Motion-Tracking-System. Abschließend untersuchen wir, wie interaktive Musiksysteme im Bereich ‚Pervasive Advertising‘ eingesetzt werden können und wie unser Ansatz genutzt werden kann, um ‚interaktive Werbejingles‘ zu realisieren

    Self-adaptivity of applications on network on chip multiprocessors: the case of fault-tolerant Kahn process networks

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    Technology scaling accompanied with higher operating frequencies and the ability to integrate more functionality in the same chip has been the driving force behind delivering higher performance computing systems at lower costs. Embedded computing systems, which have been riding the same wave of success, have evolved into complex architectures encompassing a high number of cores interconnected by an on-chip network (usually identified as Multiprocessor System-on-Chip). However these trends are hindered by issues that arise as technology scaling continues towards deep submicron scales. Firstly, growing complexity of these systems and the variability introduced by process technologies make it ever harder to perform a thorough optimization of the system at design time. Secondly, designers are faced with a reliability wall that emerges as age-related degradation reduces the lifetime of transistors, and as the probability of defects escaping post-manufacturing testing is increased. In this thesis, we take on these challenges within the context of streaming applications running in network-on-chip based parallel (not necessarily homogeneous) systems-on-chip that adopt the no-remote memory access model. In particular, this thesis tackles two main problems: (1) fault-aware online task remapping, (2) application-level self-adaptation for quality management. For the former, by viewing fault tolerance as a self-adaptation aspect, we adopt a cross-layer approach that aims at graceful performance degradation by addressing permanent faults in processing elements mostly at system-level, in particular by exploiting redundancy available in multi-core platforms. We propose an optimal solution based on an integer linear programming formulation (suitable for design time adoption) as well as heuristic-based solutions to be used at run-time. We assess the impact of our approach on the lifetime reliability. We propose two recovery schemes based on a checkpoint-and-rollback and a rollforward technique. For the latter, we propose two variants of a monitor-controller- adapter loop that adapts application-level parameters to meet performance goals. We demonstrate not only that fault tolerance and self-adaptivity can be achieved in embedded platforms, but also that it can be done without incurring large overheads. In addressing these problems, we present techniques which have been realized (depending on their characteristics) in the form of a design tool, a run-time library or a hardware core to be added to the basic architecture
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