Execution platform modeling for system-level architecture performance analysis

Today's embedded systems are designed for more complex and more computationally-intensive applications than they were a decade ago. Most if not every embedded system designed today is a sort of parallel computing system - only called differently - a platform. A platform is essentially a heterogeneous system consisting of communicating processing units of different types and mostly distributed memory units. A platform can be anything: from multiprocessors comprising task-dedicated processors and a dedicated communication network, to a (semi-)programmable multiprocessor that can run parallel processes by means of both interleaving and overlapping. However, the specification, exploration and design of application multiprocessor system platforms from user requirements is still a painstaking process that takes too long and is too costly. Our answer to the above mentioned issues is the Archer approach. It embodies: Application representations (Symbolic Programs - SP), a platform-based library of the architecture components and their configurations (all-in-hardware, all-in-software, hybrid multiprocessor, with dedicated network, hared-bus, highway, burst-bus, or hybrid network), and a mapping methodology (managing the aforementioned representations while transforming application SPs to Archer architecture components), that we have been developing and experimenting with.UBL - phd migration 201

Automatic Design of Efficient Application-centric Architectures.

As the market for embedded devices continues to grow, the demand for high performance, low cost, and low power computation grows as well. Many embedded applications perform computationally intensive tasks such as processing streaming video or audio, wireless communication, or speech recognition and must be implemented within tight power budgets. Typically, general purpose processors are not able to meet these performance and power requirements. Custom hardware in the form of loop accelerators are often used to execute the compute-intensive portions of these applications because they can achieve significantly higher levels of performance and power efficiency. Automated hardware synthesis from high level specifications is a key technology used in designing these accelerators, because the resulting hardware is correct by construction, easing verification and greatly decreasing time-to-market in the quickly evolving embedded domain. In this dissertation, a compiler-directed approach is used to design a loop accelerator from a C specification and a throughput requirement. The compiler analyzes the loop and generates a virtual architecture containing sufficient resources to sustain the required throughput. Next, a software pipelining scheduler maps the operations in the loop to the virtual architecture. Finally, the accelerator datapath is derived from the resulting schedule. In this dissertation, synthesis of different types of loop accelerators is investigated. First, the system for synthesizing single loop accelerators is detailed. In particular, a scheduler is presented that is aware of the effects of its decisions on the resulting hardware, and attempts to minimize hardware cost. Second, synthesis of multifunction loop accelerators, or accelerators capable of executing multiple loops, is presented. Such accelerators exploit coarse-grained hardware sharing across loops in order to reduce overall cost. Finally, synthesis of post-programmable accelerators is presented, allowing changes to be made to the software after an accelerator has been created. The tradeoffs between the flexibility, cost, and energy efficiency of these different types of accelerators are investigated. Automatically synthesized loop accelerators are capable of achieving order-of-magnitude gains in performance, area efficiency, and power efficiency over processors, and programmable accelerators allow software changes while maintaining highly efficient levels of computation.Ph.D.Computer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/61644/1/fank_1.pd

A design for professional laboratory experiences in teacher education

It was the purpose of this study to devise a model or design for professional laboratory experiences for teacher education. The writer took the philosophical position that conventional one-to-one placement of a student teacher with one cooperating public school teacher frequently encourages modeling or blind emulation of that teacher. The study was an attempt to design a program which would make modeling less likely

PRESTK : situation-aware presentation of messages and infotainment content for drivers

The amount of in-car information systems has dramatically increased over the last few years. These potentially mutually independent information systems presenting information to the driver increase the risk of driver distraction. In a first step, orchestrating these information systems using techniques from scheduling and presentation planning avoid conflicts when competing for scarce resources such as screen space. In a second step, the cognitive capacity of the driver as another scarce resource has to be considered. For the first step, an algorithm fulfilling the requirements of this situation is presented and evaluated. For the second step, I define the concept of System Situation Awareness (SSA) as an extension of Endsley’s Situation Awareness (SA) model. I claim that not only the driver needs to know what is happening in his environment, but also the system, e.g., the car. In order to achieve SSA, two paths of research have to be followed: (1) Assessment of cognitive load of the driver in an unobtrusive way. I propose to estimate this value using a model based on environmental data. (2) Developing model of cognitive complexity induced by messages presented by the system. Three experiments support the claims I make in my conceptual contribution to this field. A prototypical implementation of the situation-aware presentation management toolkit PRESTK is presented and shown in two demonstrators.In den letzten Jahren hat die Menge der informationsanzeigenden Systeme im Auto drastisch zugenommen. Da sie potenziell unabhängig voneinander ablaufen, erhöhen sie die Gefahr, die Aufmerksamkeit des Fahrers abzulenken. Konflikte entstehen, wenn zwei oder mehr Systeme zeitgleich auf limitierte Ressourcen wie z. B. den Bildschirmplatz zugreifen. Ein erster Schritt, diese Konflikte zu vermeiden, ist die Orchestrierung dieser Systeme mittels Techniken aus dem Bereich Scheduling und Präsentationsplanung. In einem zweiten Schritt sollte die kognitive Kapazität des Fahrers als ebenfalls limitierte Ressource berücksichtigt werden. Der Algorithmus, den ich zu Schritt 1 vorstelle und evaluiere, erfüllt alle diese Anforderungen. Zu Schritt 2 definiere ich das Konzept System Situation Awareness (SSA), basierend auf Endsley’s Konzept der Situation Awareness (SA). Dadurch wird erreicht, dass nicht nur der Fahrer sich seiner Umgebung bewusst ist, sondern auch das System (d.h. das Auto). Zu diesem Zweck m¨ussen zwei Bereiche untersucht werden: (1) Die kognitive Belastbarkeit des Fahrers unaufdringlich ermitteln. Dazu schlage ich ein Modell vor, das auf Umgebungsinformationen basiert. (2) Ein weiteres Modell soll die Komplexität der präsentierten Informationen bestimmen. Drei Experimente stützen die Behauptungen in meinem konzeptuellen Beitrag. Ein Prototyp des situationsbewussten Präsentationsmanagement-Toolkits PresTK wird vorgestellt und in zwei Demonstratoren gezeigt

Designing Resilient Manufacturing Systems In the Presence of Change

Economic and technical changes force manufacturers to redesign and enhance their operational systems. The implications of such changes within a complex system such as manufacturing and the supply chain can be very challenging. In particular, where the number of system elements and their connections result in a high level of complexity, the potential effects of a change can be expensive concerning the delivery time and cost targets, as a change to one part or element of a design requires additional changes throughout the system. Companies need to understand the characteristics of their manufacturing systems that make them resilient to change. Considered from a system perspective, the structures of the system, and its elements and connections, contribute greatly to the characteristics and behavior of the system and hence potential resilience. A change prediction method can help to analyse the change properties and improve complex systems by focusing on the underlying structural elements and dependencies. This thesis proposes a novel system change method that can enable the review of the current manufacturing system and understand how to design a more robust or adaptable system that addresses resilience. This method is a combination of matrix-based approaches and methods to assess the interaction between elements of the product and its manufacturing process in order to understand the risk of changes propagating through the system. Risk assessment across layers of a system can give valuable insight into how an element change interacts within the system. The goal of this thesis is to contribute to gaining a fundamental understanding of manufacturing systems resilience by developing a method to evaluate capabilities of changes, performance robustness or adaptability, and achieving high resilience.Universal Oil Products (a Honeywell Company); Laing O’Rourk

Production planning process optimization

Produktionsautomationssysteme sind komplexe Systeme mit viele Entitäten (Roboter, Transportsysteme usw.) die mannigfaltig aufeinander einwirken und zusammenspielen um das Ziel einer Produktendfertigung zu ermöglichen. Multiagenten-Systeme basierend auf verteilter Kontrolle sind der praktikabelste Ansatz die ansteigende Kompliziertheit solcher Systeme in den Griff zu bekommen und gleichzeitig eine flexible Anpassung des Produktionsautomationssystems an variable Rahmenbedingungen zu gewährleisten (z.B. Änderung von Produktionsstrassen oder die Koordination von Transportelementen). Für solch kritische Produktionsautomationssysteme ist eine Überprüfung aller Schritte im Entwicklungsprozess erforderlich um ein sicher funktionierendes System zu gewährleisten. Qualitätsmessungen zur Sicherstellung der Korrektheit von Systemelemente stellen bei der Zielerreichung daher einen wichtigen Schritt dar. Die Softwaresimulation des Werkstatt-Systems erlaubt sowohl Leistungsmessung einer Systemkonfiguration als auch schnellere und preiswertere Reaktion auf sich ändernde Voraussetzungen. Hinzu kommt, dass die Softwaresimulation von Produktionsautomationssystemen immer mehr einen praktikable Möglichkeit darstellt, um Produktionsvorgänge zu planen und/oder zu optimieren.Production Automation Systems are complex systems. They typically have many entities like robots, transport systems, etc. that interact in complex ways to provide production automation functions like assembly of products. The increasing complexity of these systems makes central control more and more difficult. Therefore systems with distributed control are areas of intense research such as multi-agent systems. Moreover, changing requirements for production automation systems require better system and model flexibility for e.g. easy-to-change workshop layouts or coordination of transportation elements. Meeting all this tasks makes the design of a production automation system a challenge hard to solve for designers and system engineers. For safety-critical systems like production automation systems, verification is required for all steps in the development process. Testing aims at measuring the quality of executable system elements, especially the validity of a configuration and correctness of calculated results. A particular challenge is measurement of non-functional quality requirements such as system performance before the actual hardware system is built. Software simulation of the workshop system would allow both performance measurement of a configuration and faster, cheaper reaction to changing requirements, however the validity of the simulation has to be assured. On top of this, software simulation of production automation systems can get more and more a sufficient part during the production planning and optimization process

Robot Navigation in Human Environments

For the near future, we envision service robots that will help us with everyday chores in home, office, and urban environments. These robots need to work in environments that were designed for humans and they have to collaborate with humans to fulfill their tasks. In this thesis, we propose new methods for communicating, transferring knowledge, and collaborating between humans and robots in four different navigation tasks. In the first application, we investigate how automated services for giving wayfinding directions can be improved to better address the needs of the human recipients. We propose a novel method based on inverse reinforcement learning that learns from a corpus of human-written route descriptions what amount and type of information a route description should contain. By imitating the human teachers' description style, our algorithm produces new route descriptions that sound similarly natural and convey similar information content, as we show in a user study. In the second application, we investigate how robots can leverage background information provided by humans for exploring an unknown environment more efficiently. We propose an algorithm for exploiting user-provided information such as sketches or floor plans by combining a global exploration strategy based on the solution of a traveling salesman problem with a local nearest-frontier-first exploration scheme. Our experiments show that the exploration tours are significantly shorter and that our system allows the user to effectively select the areas that the robot should explore. In the second part of this thesis, we focus on humanoid robots in home and office environments. The human-like body plan allows humanoid robots to navigate in environments and operate tools that were designed for humans, making humanoid robots suitable for a wide range of applications. As localization and mapping are prerequisites for all navigation tasks, we first introduce a novel feature descriptor for RGB-D sensor data and integrate this building block into an appearance-based simultaneous localization and mapping system that we adapt and optimize for the usage on humanoid robots. Our optimized system is able to track a real Nao humanoid robot more accurately and more robustly than existing approaches. As the third application, we investigate how humanoid robots can cover known environments efficiently with their camera, for example for inspection or search tasks. We extend an existing next-best-view approach by integrating inverse reachability maps, allowing us to efficiently sample and check collision-free full-body poses. Our approach enables the robot to inspect as much of the environment as possible. In our fourth application, we extend the coverage scenario to environments that also include articulated objects that the robot has to actively manipulate to uncover obstructed regions. We introduce algorithms for navigation subtasks that run highly parallelized on graphics processing units for embedded devices. Together with a novel heuristic for estimating utility maps, our system allows to find high-utility camera poses for efficiently covering environments with articulated objects. All techniques presented in this thesis were implemented in software and thoroughly evaluated in user studies, simulations, and experiments in both artificial and real-world environments. Our approaches advance the state of the art towards universally usable robots in everyday environments.Roboternavigation in menschlichen Umgebungen In naher Zukunft erwarten wir Serviceroboter, die uns im Haushalt, im Büro und in der Stadt alltägliche Arbeiten abnehmen. Diese Roboter müssen in für Menschen gebauten Umgebungen zurechtkommen und sie müssen mit Menschen zusammenarbeiten um ihre Aufgaben zu erledigen. In dieser Arbeit schlagen wir neue Methoden für die Kommunikation, Wissenstransfer und Zusammenarbeit zwischen Menschen und Robotern bei Navigationsaufgaben in vier Anwendungen vor. In der ersten Anwendung untersuchen wir, wie automatisierte Dienste zur Generierung von Wegbeschreibungen verbessert werden können, um die Beschreibungen besser an die Bedürfnisse der Empfänger anzupassen. Wir schlagen eine neue Methode vor, die inverses bestärkendes Lernen nutzt, um aus einem Korpus von von Menschen geschriebenen Wegbeschreibungen zu lernen, wie viel und welche Art von Information eine Wegbeschreibung enthalten sollte. Indem unser Algorithmus den Stil der Wegbeschreibungen der menschlichen Lehrer imitiert, kann der Algorithmus neue Wegbeschreibungen erzeugen, die sich ähnlich natürlich anhören und einen ähnlichen Informationsgehalt vermitteln, was wir in einer Benutzerstudie zeigen. In der zweiten Anwendung untersuchen wir, wie Roboter von Menschen bereitgestellte Hintergrundinformationen nutzen können, um eine bisher unbekannte Umgebung schneller zu erkunden. Wir schlagen einen Algorithmus vor, der Hintergrundinformationen wie Gebäudegrundrisse oder Skizzen nutzt, indem er eine globale Explorationsstrategie basierend auf der Lösung eines Problems des Handlungsreisenden kombiniert mit einer lokalen Explorationsstrategie. Unsere Experimente zeigen, dass die Erkundungstouren signifikant kürzer werden und dass der Benutzer mit unserem System effektiv die zu erkundenden Regionen spezifizieren kann. Der zweite Teil dieser Arbeit konzentriert sich auf humanoide Roboter in Umgebungen zu Hause und im Büro. Der menschenähnliche Körperbau ermöglicht es humanoiden Robotern, in Umgebungen zu navigieren und Werkzeuge zu benutzen, die für Menschen gebaut wurden, wodurch humanoide Roboter für vielfältige Aufgaben einsetzbar sind. Da Lokalisierung und Kartierung Grundvoraussetzungen für alle Navigationsaufgaben sind, führen wir zunächst einen neuen Merkmalsdeskriptor für RGB-D-Sensordaten ein und integrieren diesen Baustein in ein erscheinungsbasiertes simultanes Lokalisierungs- und Kartierungsverfahren, das wir an die Besonderheiten von humanoiden Robotern anpassen und optimieren. Unser System kann die Position eines realen humanoiden Roboters genauer und robuster verfolgen, als es mit existierenden Ansätzen möglich ist. Als dritte Anwendung untersuchen wir, wie humanoide Roboter bekannte Umgebungen effizient mit ihrer Kamera abdecken können, beispielsweise zu Inspektionszwecken oder zum Suchen eines Gegenstands. Wir erweitern ein bestehendes Verfahren, das die nächstbeste Beobachtungsposition berechnet, durch inverse Erreichbarkeitskarten, wodurch wir kollisionsfreie Ganzkörperposen effizient generieren und prüfen können. Unser Ansatz ermöglicht es dem Roboter, so viel wie möglich von der Umgebung zu untersuchen. In unserer vierten Anwendung erweitern wir dieses Szenario um Umgebungen, die auch bewegbare Gegenstände enthalten, die der Roboter aktiv bewegen muss um verdeckte Regionen zu sehen. Wir führen Algorithmen für Teilprobleme ein, die hoch parallelisiert auf Grafikkarten von eingebetteten Systemen ausgeführt werden. Zusammen mit einer neuen Heuristik zur Schätzung von Nutzenkarten ermöglicht dies unserem System Beobachtungspunkte mit hohem Nutzen zu finden, um Umgebungen mit bewegbaren Objekten effizient zu inspizieren. Alle vorgestellten Techniken wurden in Software implementiert und sorgfältig evaluiert in Benutzerstudien, Simulationen und Experimenten in künstlichen und realen Umgebungen. Unsere Verfahren bringen den Stand der Forschung voran in Richtung universell einsetzbarer Roboter in alltäglichen Umgebungen

NBS monograph

From Introduction: "This is the second in a series of reports concerned with research and development requirements and areas of continuing concern in the computer and information sciences and technologies.

Special Libraries, September 1975

Volume 66, Issue 9https://scholarworks.sjsu.edu/sla_sl_1975/1007/thumbnail.jp