9,359 research outputs found
Verifying service continuity in a satellite reconfiguration procedure: application to a satellite
The paper discusses the use of the TURTLE UML profile to model and verify service continuity during dynamic reconfiguration of embedded software, and space-based telecommunication software in particular. TURTLE extends UML class diagrams with composition operators, and activity diagrams with temporal operators. Translating TURTLE to the formal description technique RT-LOTOS gives the profile a formal semantics and makes it possible to reuse verification techniques implemented by the RTL, the RT-LOTOS toolkit developed at LAAS-CNRS. The paper proposes a modeling and formal validation methodology based on TURTLE and RTL, and discusses its application to a payload software application in charge of an embedded packet switch. The paper demonstrates the benefits of using TURTLE to prove service continuity for dynamic reconfiguration of embedded software
Development of Reconfigurable Distributed Embedded Systems with a Model-Driven Approach
International audienceIn this paper, we propose a model-driven approach allowing to build reconfigurable distributed real-time embedded (DRE) systems. The constant growth of the complexity and the required autonomy of embedded software systems management give the dynamic reconfiguration a big importance. New challenges to apply the dynamic reconfiguration at model level as well as runtime support level are required. In this direction, the development of reconfigurable DRE systems according to traditional processes is not applicable. New methods are required to build and to supply reconfigurable embedded software architectures. In this context, we propose an model-driven engineering based approach that enables to design reconfigurable DRE systems with execution framework support. This approach leads the designer to specify step by step his/her system from a model to another one more refined until the targeted model is reached. This targeted model is related to a specific platform leading to the generation of the most part of the system implementation. We also develop a new middleware that supports reconfigurable DRE systems
Component Substitution through Dynamic Reconfigurations
Component substitution has numerous practical applications and constitutes an
active research topic. This paper proposes to enrich an existing
component-based framework--a model with dynamic reconfigurations making the
system evolve--with a new reconfiguration operation which "substitutes"
components by other components, and to study its impact on sequences of dynamic
reconfigurations.
Firstly, we define substitutability constraints which ensure the component
encapsulation while performing reconfigurations by component substitutions.
Then, we integrate them into a substitutability-based simulation to take these
substituting reconfigurations into account on sequences of dynamic
reconfigurations. Thirdly, as this new relation being in general undecidable
for infinite-state systems, we propose a semi-algorithm to check it on the fly.
Finally, we report on experimentations using the B tools to show the
feasibility of the developed approach, and to illustrate the paper's proposals
on an example of the HTTP server.Comment: In Proceedings FESCA 2014, arXiv:1404.043
Smart technologies for effective reconfiguration: the FASTER approach
Current and future computing systems increasingly require that their functionality stays flexible after the system is operational, in order to cope with changing user requirements and improvements in system features, i.e. changing protocols and data-coding standards, evolving demands for support of different user applications, and newly emerging applications in communication, computing and consumer electronics. Therefore, extending the functionality and the lifetime of products requires the addition of new functionality to track and satisfy the customers needs and market and technology trends. Many contemporary products along with the software part incorporate hardware accelerators for reasons of performance and power efficiency. While adaptivity of software is straightforward, adaptation of the hardware to changing requirements constitutes a challenging problem requiring delicate solutions. The FASTER (Facilitating Analysis and Synthesis Technologies for Effective Reconfiguration) project aims at introducing a complete methodology to allow designers to easily implement a system specification on a platform which includes a general purpose processor combined with multiple accelerators running on an FPGA, taking as input a high-level description and fully exploiting, both at design time and at run time, the capabilities of partial dynamic reconfiguration. The goal is that for selected application domains, the FASTER toolchain will be able to reduce the design and verification time of complex reconfigurable systems providing additional novel verification features that are not available in existing tool flows
Contradiction, intervention and urban low carbon transitions
This paper presents an analysis of contradictions in urban low carbon transitions as engines of change. Following Kojéve’s reading of contradiction in Hegel's oeuvre, I argue that contradiction is a constitutive feature of low carbon interventions. This is an alternative to conventional readings of contradiction as a provisional encounter of opposites in which one will eventually cancel the other. I unpack the concept of contradiction in three ways: first, by displaying a Hegelian-inspired understanding of contradiction in relationship with change, time and desire; second, by explaining how inherent contradictions can be read in relation to the excesses that characterise the deployment of methods of calculation in low carbon interventions; and third, by situating these contradictions within the overall dynamics of carbon governance and purposive attempts to bring about a low carbon transition. The paper explores the practical implications of this analysis in a case of low carbon interventions in social housing in Ljubljana, Slovenia. The case study shows that contradictions are at the heart of low carbon interventions. In this context, contradiction analysis may provide a direction towards broader reconfigurations of social and technological practices and generate a desire to change
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