13 research outputs found

    Analysis as first-class citizens – an application to Architecture Description Languages

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    Architecture Description Languages (ADLs) support modeling and analysis of systems through models transformation and exploration. Various contributions made proposals to bring verification capabilities to designers through model-based frame- works and illustrated benefits to the overall system quality. Model-level analyses are usually performed as an exogenous, unidirectional and semantically weak transformation towards a third-party model. We claim such process can be incomplete and/or inefficient because gathered results lead to evolution of the primary model. This is particularly problematic for the design of Distributed Real-Time Embedded (DRE) systems that has to tackle many concerns like time, security or safety. In this paper, we argue why analysis should no longer be considered as a side step in the design process but, rather, should be embedded as a first-class citizen in the model itself. We review several standardized architecture description languages, which consider analysis as a goal. As an element of solution, we introduce current work on the definition of a language dedicated to the analysis of models within the scope of one particular ADL, namely the Architecture Analysis and Design Language (AADL)

    Performanzanalyse von Multiprozessor-Echtzeitsystemen mit gemeinsamen Ressourcen

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    Modular Avionics Software Integration on Multi-Core COTS : certification-Compliant Methodology and Timing Analysis Metrics for Legacy Software Reuse in Modern Aerospace Systems

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    Interference in multicores is undesirable for hard real-time systems and especially in the aerospace industry, for which it is mandatory to ensure beforehand timing predictability and deadlines enforcement in a system runtime behavior, in order to be granted acceptance by certification authorities. The goal of this thesis is to propose an approach for multi-core integration of legacy IMA software, without any hardware nor software modification, and which complies as much as possible to current, incremental certification and IMA key concepts such as robust time and space partitioning. The motivations of this thesis are to stick as much as possible to the current IMA software integration process in order to maximize the chances of acceptation by avionics industries of the contributions of this thesis, but also because the current process has long been proven efficient on aerospace systems currently in usage. Another motivation is to minimize the extra effort needed to provide certification authorities with timing-related verification information required when seeking approval. As a secondary goal depending on the possibilities, the contributions should offer design optimization features, and help reduce the time-to-market by automating some steps of the design and verification process. This thesis proposes two complete methodologies for IMA integration on multi-core COTS. Each of them offers different advantages and has different drawbacks, and therefore each of them may correspond to its own, complementary situations. One fits all avionics and certification requirements of incremental verification and robust partitioning and therefore fits up to DAL A applications, while the other offers maximum Size, Weight and Power (SWaP) optimization and fits either up to DAL C applications, multipartition applications or non-IMA applications. The methodologies are said to be "complete" because this thesis provides all necessary metrics to go through all steps of the software integration process. More specifically, this includes, for each strategy: - a static timing analysis for safely upper-bounding inter-core interference, and deriving the corresponding WCET upper-bounds for each task. - a Constraint Programming (CP) formulation for automated software/hardware allocation; the resulting allocation is correct by construction since the CP process embraces the proposed timing analysis mentioned earlier. - a CP formulation for automated schedule generation; the resulting schedule is correct by construction since the CP process embraces the proposed timing analysis mentioned earlier

    A REFERENCE ARCHITECTURE OF HUMAN CYBER PHYSICAL SYSTEMS PART I: CONCEPTUAL STRUCTURE

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    We propose a reference architecture of safety-critical or industry-critical human cyber-physical systems (CPSs) capable of expressing essential classes of system-level interactions between CPS and humans relevant for the societal acceptance of such systems. To reach this quality gate, the expressivity of the model must go beyond classical viewpoints such as operational, functional, architectural views and views used for safety and security analysis. The model does so by incorporating elements of such systems for mutual introspections in situational awareness, capabilities, and intentions in order to enable a synergetic, trusted relation in the interaction of humans and CPSs, which we see as a prerequisite for their societal acceptance. The reference architecture is represented as a metamodel incorporating conceptual and behavioral semantic aspects. We illustrate the key concepts of the metamodel with examples from smart grids, cooperative autonomous driving, and crisis manage

    IEEE/NASA Workshop on Leveraging Applications of Formal Methods, Verification, and Validation

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    This volume contains the Preliminary Proceedings of the 2005 IEEE ISoLA Workshop on Leveraging Applications of Formal Methods, Verification, and Validation, with a special track on the theme of Formal Methods in Human and Robotic Space Exploration. The workshop was held on 23-24 September 2005 at the Loyola College Graduate Center, Columbia, MD, USA. The idea behind the Workshop arose from the experience and feedback of ISoLA 2004, the 1st International Symposium on Leveraging Applications of Formal Methods held in Paphos (Cyprus) last October-November. ISoLA 2004 served the need of providing a forum for developers, users, and researchers to discuss issues related to the adoption and use of rigorous tools and methods for the specification, analysis, verification, certification, construction, test, and maintenance of systems from the point of view of their different application domains

    NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 35: The use of computer networks in aerospace engineering

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    This research used survey research to explore and describe the use of computer networks by aerospace engineers. The study population included 2000 randomly selected U.S. aerospace engineers and scientists who subscribed to Aerospace Engineering. A total of 950 usable questionnaires were received by the cutoff date of July 1994. Study results contribute to existing knowledge about both computer network use and the nature of engineering work and communication. We found that 74 percent of mail survey respondents personally used computer networks. Electronic mail, file transfer, and remote login were the most widely used applications. Networks were used less often than face-to-face interactions in performing work tasks, but about equally with reading and telephone conversations, and more often than mail or fax. Network use was associated with a range of technical, organizational, and personal factors: lack of compatibility across systems, cost, inadequate access and training, and unwillingness to embrace new technologies and modes of work appear to discourage network use. The greatest positive impacts from networking appear to be increases in the amount of accurate and timely information available, better exchange of ideas across organizational boundaries, and enhanced work flexibility, efficiency, and quality. Involvement with classified or proprietary data and type of organizational structure did not distinguish network users from nonusers. The findings can be used by people involved in the design and implementation of networks in engineering communities to inform the development of more effective networking systems, services, and policies

    Modeling Towards Incremental Early Analyzability of Networked Avionics Systems Using Virtual Integration

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    With the advance of hardware technology, more features are incrementally added to already existing networked systems. Avionics has a stronger tendency to use preexisting applications due to its complexity and scale. As resource sharing becomes intense among the network and the computing modules, it has become a difficult task for the system designer to make confident architectural decisions even for incremental changes. Providing a tailored environment to model and analyze incremental changes requires a combination of software tools and hardware support.We have built a virtual integration tool called ASIIST which can provide a worst-case end-to-end latency of data that is sent through a network and the internal bus architecture of the end-systems. Also, we have devised a new real-time switching algorithm which guarantees the worst-case network delay of preexisting network traffic under feasible conditions. With the real-time switch support, ASIIST can provide an early modularized analysis of the end-to-end latency to make architectural design choices and incremental changes easier for the user. © 2012 ACM.

    Modeling Towards Incremental Early Analyzability of Networked Avionics Systems Using Virtual Integration

    No full text
    With the advance of hardware technology, more features are incrementally added to already existing networked systems. Avionics has a stronger tendency to use preexisting applications due to its complexity and scale. As resource sharing becomes intense among the network and the computing modules, it has become a difficult task for the system designer to make confident architectural decisions even for incremental changes. Providing a tailored environment to model and analyze incremental changes requires a combination of software tools and hardware support. We have built a virtual integration tool called ASIIST which can provide a worst-case end-to-end latency of data that is sent through a network and the internal bus architecture of the end-systems. Also, we have devised a new real-time switching algorithm which guarantees the worst-case network delay of preexisting network traffic under feasible conditions. With the real-time switch support, ASIIST can provide an early modularized analysis of the end-to-end latency to make architectural design choices and incremental changes easier for the user.This work was supported in part by NSF CNS 06-49885 SGER, NSF CCR-3-25716, and by ONR N00014-05-0739. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of sponsors
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