Abstract

Service-oriented computing is calling for novel computational models and languages with primitives for client-server interaction, orchestration and unexpected events handling. We present CaSPiS , a process calculus where the notions of session and pipelining play a central role. Sessions are two-sided and can be equipped with protocols executed by each side. Pipelining permits orchestrating the flow of data produced by different sessions. The calculus is also equipped with operators for handling (unexpected) termination of the partner's side of a session. Several examples are presented to provide evidence for the flexibility of the chosen set of primitives. Our main result shows that in CaSPiS it is possible to program a "graceful termination" of nested sessions, which guarantees that no session is forced to hang forever after the loss of its partner. Document type: Part of book or chapter of book

Abstract

Conference of 10th IEEE International Symposium on Industrial Embedded Systems, SIES 2015 ; Conference Date: 8 June 2015 Through 10 June 2015; Conference Code:116797; International audience; Many-core architectures are promising hardware to design hard real-time systems as they are based on simpler and thus more predictable processors than multi-core systems. However, the worst-case behavior of the Network-on-Chip (NoC) for both inter-core and core to external memories or peripherals communications must be established. Several NoCs targeting hard real-time systems, made of specific hardware extensions, have been designed. However, none of these extensions are currently available in commercially existing NoC-based many-core architectures, that instead rely on wormhole switching with round-robin arbitration. In this paper, we thus demonstrate three properties of such NoC-based wormhole networks to identify worst-case scenarios and reduce the pessimism when modeling flows in contentions. We then describe and evaluate an algorithm to compute Worst-Case Traversal Time (WCTT) of flows that uses these properties. In particular, our results show that the pessimism can be reduced up to 50% compared to current state-of-the-art real-time packet schedulability analysis.

Abstract

The loss of stability is critical regarding thin-walled composite structures which are widespread in weight critical applications. For the example of omega-stringer stiffened panels, the buckling and postbuckling behavior is investigated using closed-form analytical approximate solutions. They are derived based on energy methods and their focus lies on local stability behavior. Hereby, different load cases are included and the quality of the computational models is assessed in comparison to Levy solutions or finite element analyses.