| 1. |
- Aysan, Hüseyin, et al.
(författare)
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A Cascading Redundancy Approach for Dependable Real-Time Systems
- 2009
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Ingår i: Proceedings - 15th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications, RTCSA 2009. - 9780769537870 ; , s. 467-476
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Konferensbidrag (refereegranskat)abstract
- Dependable real-time systems typically consist of tasks of multiple criticality levels and scheduling them in a fault-tolerantmanner is a challenging problem. Redundancy in the physical and temporal domains for achieving fault tolerance has been often dealt independently based on the types of errors one needs to tolerate. To our knowledge, there had been no work which tries to integrate fault tolerant scheduling and multiple redundancy mechanisms. In this paper we propose a novel cascading redundancy approach within a generic fault tolerant scheduling framework. The proposed approach is capable of tolerating errors with a wider coverage (with respect to error frequency and error types) than time and space redundancy in isolation, allows tasks with mixed criticality levels, is independent of the scheduling technique and, above all, ensures that every critical task instance can be feasibly replicated in both time and space.
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| 2. |
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| 3. |
- Bohlin, Markus, et al.
(författare)
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Simulation-Based Timing Analysis of Complex Real-Time Systems
- 2009
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Ingår i: 2009 15TH IEEE INTERNATIONAL CONFERENCE ON EMBEDDED AND REAL-TIME COMPUTING SYSTEMS AND APPLICATIONS, PROCEEDINGS. - 9780769537870 ; , s. 321-328
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Konferensbidrag (refereegranskat)abstract
- This paper presents an efficient best-effort approach for simulation-based timing analysis of complex real- time systems. The method can handle in principle any software design that can be simulated, and is based on controlling simulation input using a simple yet novel hill- climbing algorithm. Unlike previous approaches, the new algorithm directly manipulates simulation parameters such as execution times, arrival jitter and input. An evaluation is presented using six different simulation models, and two other simulation methods as reference: Monte Carlo simulation and MABERA. The new method proposed in this paper was 4-11% more accurate while at the same time 42 times faster, on average, than the reference methods.
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| 4. |
- Bygde, Stefan, et al.
(författare)
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An Efficient Algorithm for Parametric WCET Calculation
- 2009
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Ingår i: 2009 15TH IEEE INTERNATIONAL CONFERENCE ON EMBEDDED AND REAL-TIME COMPUTING SYSTEMS AND APPLICATIONS, PROCEEDINGS. - LOS ALAMITOS : IEEE COMPUTER SOC. - 9780769537870 ; , s. 13-21
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Konferensbidrag (refereegranskat)abstract
- Static WCET analysis is a process dedicated to derive a safe upper bound of the worst-case execution time of a program. In many real-time systems, however, a constant global WCET estimate is not always so useful since a program may behave very differently depending on its configuration or mode. A parametric WCET analysis derives the upper bound as formula rather than a constant. This paper presents a new efficient algorithm that can obtain a safe parametric estimate of the WCET of a program. This algorithm is evaluated on a large set of benchmarks and compared to a previous approach to parametric WCET calculation. The evaluation shows that the new algorithm, to the cost of some imprecision, scales much better and can handle more realistic programs than the previous approach.
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| 5. |
- Samii, Soheil, et al.
(författare)
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Immune Genetic Algorithms for Optimization of Task Priorities and FlexRay Frame Identifiers
- 2009
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Ingår i: <em>Intl. Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA), Beijing, China, August 24-26, 2009.</em>. - : IEEE COMPUTER SOC. - 9780769537870 ; , s. 486-493
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Konferensbidrag (refereegranskat)abstract
- FlexRay is an automotive communication protocol that combines the comprehensive time-triggered paradigm with an adaptive phase that is more suitable for event-based communication. We study optimization of average response times by assigning priorities and frame identifiers to tasks and messages. Our optimization approach is based on immune genetic algorithms, where in addition to the crossover and mutation operators, we use a vaccination operator that results in considerable improvements in optimization time and quality.
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