Research and Education in Computational Science and Engineering

Over the past two decades the field of computational science and engineering (CSE) has penetrated both basic and applied research in academia, industry, and laboratories to advance discovery, optimize systems, support decision-makers, and educate the scientific and engineering workforce. Informed by centuries of theory and experiment, CSE performs computational experiments to answer questions that neither theory nor experiment alone is equipped to answer. CSE provides scientists and engineers of all persuasions with algorithmic inventions and software systems that transcend disciplines and scales. Carried on a wave of digital technology, CSE brings the power of parallelism to bear on troves of data. Mathematics-based advanced computing has become a prevalent means of discovery and innovation in essentially all areas of science, engineering, technology, and society; and the CSE community is at the core of this transformation. However, a combination of disruptive developments---including the architectural complexity of extreme-scale computing, the data revolution that engulfs the planet, and the specialization required to follow the applications to new frontiers---is redefining the scope and reach of the CSE endeavor. This report describes the rapid expansion of CSE and the challenges to sustaining its bold advances. The report also presents strategies and directions for CSE research and education for the next decade.Comment: Major revision, to appear in SIAM Revie

Developing a distributed electronic health-record store for India

The DIGHT project is addressing the problem of building a scalable and highly available information store for the Electronic Health Records (EHRs) of the over one billion citizens of India

Zuverlässige und Energieeffiziente gemischt-kritische Echtzeit On-Chip Systeme

Multi- and many-core embedded systems are increasingly becoming the target for many applications that require high performance under varying conditions. A resulting challenge is the control, and reliable operation of such complex multiprocessing architectures under changes, e.g., high temperature and degradation. In mixed-criticality systems where many applications with varying criticalities are consolidated on the same execution platform, fundamental isolation requirements to guarantee non-interference of critical functions are crucially important. While Networks-on-Chip (NoCs) are the prevalent solution to provide scalable and efficient interconnects for the multiprocessing architectures, their associated energy consumption has immensely increased. Specifically, hard real-time NoCs must manifest limited energy consumption as thermal runaway in such a core shared resource jeopardizes the whole system guarantees. Thus, dynamic energy management of NoCs, as opposed to the related work static solutions, is highly necessary to save energy and decrease temperature, while preserving essential temporal requirements. In this thesis, we introduce a centralized management to provide energy-aware NoCs for hard real-time systems. The design relies on an energy control network, developed on top of an existing switch arbitration network to allow isolation between energy optimization and data transmission. The energy control layer includes local units called Power-Aware NoC controllers that dynamically optimize NoC energy depending on the global state and applications’ temporal requirements. Furthermore, to adapt to abnormal situations that might occur in the system due to degradation, we extend the concept of NoC energy control to include the entire system scope. That is, online resource management employing hierarchical control layers to treat system degradation (imminent core failures) is supported. The mechanism applies system reconfiguration that involves workload migration. For mixed-criticality systems, it allows flexible boundaries between safety-critical and non-critical subsystems to safely apply the reconfiguration, preserving fundamental safety requirements and temporal predictability. Simulation and formal analysis-based experiments on various realistic usecases and benchmarks are conducted showing significant improvements in NoC energy-savings and in treatment of system degradation for mixed-criticality systems improving dependability over the status quo.Eingebettete Many- und Multi-core-Systeme werden zunehmend das Ziel für Anwendungen, die hohe Anfordungen unter unterschiedlichen Bedinungen haben. Für solche hochkomplexed Multi-Prozessor-Systeme ist es eine grosse Herausforderung zuverlässigen Betrieb sicherzustellen, insbesondere wenn sich die Umgebungseinflüsse verändern. In Systeme mit gemischter Kritikalität, in denen viele Anwendungen mit unterschiedlicher Kritikalität auf derselben Ausführungsplattform bedient werden müssen, sind grundlegende Isolationsanforderungen zur Gewährleistung der Nichteinmischung kritischer Funktionen von entscheidender Bedeutung. Während On-Chip Netzwerke (NoCs) häufig als skalierbare Verbindung für die Multiprozessor-Architekturen eingesetzt werden, ist der damit verbundene Energieverbrauch immens gestiegen. Daher sind dynamische Plattformverwaltungen, im Gegensatz zu den statischen, zwingend notwendig, um ein System an die oben genannten Veränderungen anzupassen und gleichzeitig Timing zu gewährleisten. In dieser Arbeit entwickeln wir energieeffiziente NoCs für harte Echtzeitsysteme. Das Design basiert auf einem Energiekontrollnetzwerk, das auf einem bestehenden Switch-Arbitration-Netzwerk entwickelt wurde, um eine Isolierung zwischen Energieoptimierung und Datenübertragung zu ermöglichen. Die Energiesteuerungsschicht umfasst lokale Einheiten, die als Power-Aware NoC-Controllers bezeichnet werden und die die NoC-Energie in Abhängigkeit vom globalen Zustand und den zeitlichen Anforderungen der Anwendungen optimieren. Darüber hinaus wird das Konzept der NoC-Energiekontrolle zur Anpassung an Anomalien, die aufgrund von Abnutzung auftreten können, auf den gesamten Systemumfang ausgedehnt. Online- Ressourcenverwaltungen, die hierarchische Kontrollschichten zur Behandlung Abnutzung (drohender Kernausfälle) einsetzen, werden bereitgestellt. Bei Systemen mit gemischter Kritikalität erlaubt es flexible Grenzen zwischen sicherheitskritischen und unkritischen Subsystemen, um die Rekonfiguration sicher anzuwenden, wobei grundlegende Sicherheitsanforderungen erhalten bleiben und Timing Vorhersehbarkeit. Experimente werden auf der Basis von Simulationen und formalen Analysen zu verschiedenen realistischen Anwendungsfallen und Benchmarks durchgeführt, die signifikanten Verbesserungen bei On-Chip Netzwerke-Energieeinsparungen und bei der Behandlung von Abnutzung für Systeme mit gemischter Kritikalität zur Verbesserung die Systemstabilität gegenüber dem bisherigen Status quo zeigen

Innovation in manufacturing through digital technologies and applications: Thoughts and Reflections on Industry 4.0

The rapid pace of developments in digital technologies offers many opportunities to increase the efficiency, flexibility and sophistication of manufacturing processes; including the potential for easier customisation, lower volumes and rapid changeover of products within the same manufacturing cell or line. A number of initiatives on this theme have been proposed around the world to support national industries under names such as Industry 4.0 (Industrie 4.0 in Germany, Made-in-China in China and Made Smarter in the UK). This book presents an overview of the state of art and upcoming developments in digital technologies pertaining to manufacturing. The starting point is an introduction on Industry 4.0 and its potential for enhancing the manufacturing process. Later on moving to the design of smart (that is digitally driven) business processes which are going to rely on sensing of all relevant parameters, gathering, storing and processing the data from these sensors, using computing power and intelligence at the most appropriate points in the digital workflow including application of edge computing and parallel processing. A key component of this workflow is the application of Artificial Intelligence and particularly techniques in Machine Learning to derive actionable information from this data; be it real-time automated responses such as actuating transducers or informing human operators to follow specified standard operating procedures or providing management data for operational and strategic planning. Further consideration also needs to be given to the properties and behaviours of particular machines that are controlled and materials that are transformed during the manufacturing process and this is sometimes referred to as Operational Technology (OT) as opposed to IT. The digital capture of these properties and behaviours can then be used to define so-called Cyber Physical Systems. Given the power of these digital technologies it is of paramount importance that they operate safely and are not vulnerable to malicious interference. Industry 4.0 brings unprecedented cybersecurity challenges to manufacturing and the overall industrial sector and the case is made here that new codes of practice are needed for the combined Information Technology and Operational Technology worlds, but with a framework that should be native to Industry 4.0. Current computing technologies are also able to go in other directions than supporting the digital ‘sense to action’ process described above. One of these is to use digital technologies to enhance the ability of the human operators who are still essential within the manufacturing process. One such technology, that has recently become accessible for widespread adoption, is Augmented Reality, providing operators with real-time additional information in situ with the machines that they interact with in their workspace in a hands-free mode. Finally, two linked chapters discuss the specific application of digital technologies to High Pressure Die Casting (HDPC) of Magnesium components. Optimizing the HPDC process is a key task for increasing productivity and reducing defective parts and the first chapter provides an overview of the HPDC process with attention to the most common defects and their sources. It does this by first looking at real-time process control mechanisms, understanding the various process variables and assessing their impact on the end product quality. This understanding drives the choice of sensing methods and the associated smart digital workflow to allow real-time control and mitigation of variation in the identified variables. Also, data from this workflow can be captured and used for the design of optimised dies and associated processes

The design of organisations, products and processes for strategic flexibility : executive summary

Technological innovation and globalisation are driving profound economic, political and cultural changes. There is a widespread acknowledgement that organisations need to be more strategically flexible to cope with increased levels of competition and market change. The research reported here has two objectives. The first is that of identifying the causes of strategic flexibility in organisations, and the second being to implement methods of improving strategic flexibility. A model of decision-making behaviour has been developed, which identifies the areas of individual and group decision-making behaviour that affect strategic flexibility. The model has general applicability. A significant cause of strategic inflexibility is a behavioural. dysfunction in individuals that produces a much wider dysfunction in the organisation. The same model also provides the basis for the evaluation and improvement of such behaviours. This has led to the development of processes and tools to reduce the barriers to adopting high quality decision-making behaviour. However, individual behavioural. change, while being an essential foundation, is insufficient on its own to achieve high rates of organisational and technological adaptation at low levels of disruption. The second objective has been to implement a systematic process for integrating all players in a strategically flexible organisation. In the absence of a consistent, systematic process, particularly for organisational and technological innovation, a design model of the business has been originated and developed. This has been shown to be applicable to a wide range of organisational cultures and integrates recent trends in organisational thinking. Individual innovations in processes and tools, which have been central to the development and introduction of the design model, have been implemented in an organisation. These innovations are in the areas of innovation management, portfolio management, product targeting and target agreement, and are described to achieve wider application. The concept of the brand has been shown to be a powerful 'attractor' to develop an organisation's fundamental relationship with its environment in the long, medium and short term. Because the values of a brand represent basic human motivational values, they provide stability for long term planning and can align internal decision-making values, innovation and core competencies to the benefit of the organisation and their workers, their customers and the wider environment. The research work has shown that an organisation can meet the simultaneous requirements of design speed, knowledge reuse, semi-independent decision-making and creativity at the lowest possible level of the organisation. The concepts and tools are therefore valuable in supporting a step-change in the performance of conventional and virtual organisations. The modular partitioning of organisations, products and processes is compatible with the design model of the business, -and the strategies are synergistic. While modularity in a traditional organisation. could lead to decay and loss of strategic flexibility, its integration within the design model framework supports a dynamically unstable, but continuously innovative and long-lived organisation

Development and certification of mixed-criticality embedded systems based on probabilistic timing analysis

An increasing variety of emerging systems relentlessly replaces or augments the functionality of mechanical subsystems with embedded electronics. For quantity, complexity, and use, the safety of such subsystems is an increasingly important matter. Accordingly, those systems are subject to safety certification to demonstrate system's safety by rigorous development processes and hardware/software constraints. The massive augment in embedded processors' complexity renders the arduous certification task significantly harder to achieve. The focus of this thesis is to address the certification challenges in multicore architectures: despite their potential to integrate several applications on a single platform, their inherent complexity imperils their timing predictability and certification. Recently, the Measurement-Based Probabilistic Timing Analysis (MBPTA) technique emerged as an alternative to deal with hardware/software complexity. The innovation that MBPTA brings about is, however, a major step from current certification procedures and standards. The particular contributions of this Thesis include: (i) the definition of certification arguments for mixed-criticality integration upon multicore processors. In particular we propose a set of safety mechanisms and procedures as required to comply with functional safety standards. For timing predictability, (ii) we present a quantitative approach to assess the likelihood of execution-time exceedance events with respect to the risk reduction requirements on safety standards. To this end, we build upon the MBPTA approach and we present the design of a safety-related source of randomization (SoR), that plays a key role in the platform-level randomization needed by MBPTA. And (iii) we evaluate current certification guidance with respect to emerging high performance design trends like caches. Overall, this Thesis pushes the certification limits in the use of multicore and MBPTA technology in Critical Real-Time Embedded Systems (CRTES) and paves the way towards their adoption in industry.Una creciente variedad de sistemas emergentes reemplazan o aumentan la funcionalidad de subsistemas mecánicos con componentes electrónicos embebidos. El aumento en la cantidad y complejidad de dichos subsistemas electrónicos así como su cometido, hacen de su seguridad una cuestión de creciente importancia. Tanto es así que la comercialización de estos sistemas críticos está sujeta a rigurosos procesos de certificación donde se garantiza la seguridad del sistema mediante estrictas restricciones en el proceso de desarrollo y diseño de su hardware y software. Esta tesis trata de abordar los nuevos retos y dificultades dadas por la introducción de procesadores multi-núcleo en dichos sistemas críticos: aunque su mayor rendimiento despierta el interés de la industria para integrar múltiples aplicaciones en una sola plataforma, suponen una mayor complejidad. Su arquitectura desafía su análisis temporal mediante los métodos tradicionales y, asimismo, su certificación es cada vez más compleja y costosa. Con el fin de lidiar con estas limitaciones, recientemente se ha desarrollado una novedosa técnica de análisis temporal probabilístico basado en medidas (MBPTA). La innovación de esta técnica, sin embargo, supone un gran cambio cultural respecto a los estándares y procedimientos tradicionales de certificación. En esta línea, las contribuciones de esta tesis están agrupadas en tres ejes principales: (i) definición de argumentos de seguridad para la certificación de aplicaciones de criticidad-mixta sobre plataformas multi-núcleo. Se definen, en particular, mecanismos de seguridad, técnicas de diagnóstico y reacción de faltas acorde con el estándar IEC 61508 sobre una arquitectura multi-núcleo de referencia. Respecto al análisis temporal, (ii) presentamos la cuantificación de la probabilidad de exceder un límite temporal y su relación con los requisitos de reducción de riesgos derivados de los estándares de seguridad funcional. Con este fin, nos basamos en la técnica MBPTA y presentamos el diseño de una fuente de números aleatorios segura; un componente clave para conseguir las propiedades aleatorias requeridas por MBPTA a nivel de plataforma. Por último, (iii) extrapolamos las guías actuales para la certificación de arquitecturas multi-núcleo a una solución comercial de 8 núcleos y las evaluamos con respecto a las tendencias emergentes de diseño de alto rendimiento (caches). Con estas contribuciones, esta tesis trata de abordar los retos que el uso de procesadores multi-núcleo y MBPTA implican en el proceso de certificación de sistemas críticos de tiempo real y facilita, de esta forma, su adopción por la industria.Postprint (published version

Project BeARCAT : Baselining, Automation and Response for CAV Testbed Cyber Security : Connected Vehicle & Infrastructure Security Assessment

Connected, software-based systems are a driver in advancing the technology of transportation systems. Advanced automated and autonomous vehicles, together with electrification, will help reduce congestion, accidents and emissions. Meanwhile, vehicle manufacturers see advanced technology as enhancing their products in a competitive market. However, as many decades of using home and enterprise computer systems have shown, connectivity allows a system to become a target for criminal intentions. Cyber-based threats to any system are a problem; in transportation, there is the added safety implication of dealing with moving vehicles and the passengers within