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1	On the three-state weather model of transmission line failures. Csenki, Attila January 2007 (has links) No / Recent work by Billinton et al. has highlighted the importance of employing more than one adverse weather state when modelling transmission line failures by Markov processes. In the present work the structure of the modelling Markov process is identified, allowing the rate matrix to be written in a closed form using Kronecker matrix operations. This approach allows larger models to be handled safely and with ease. The MAXIMA implementation of two asymptotic reliability indices for such systems is addressed, exemplifying the combination of symbolic and numerical steps, perhaps not seen in this context before. It is also indicated how the three-state weather model can be extended to a multi-state model, while retaining the scope of the proposed closed-form expression for the rate matrix. Some possible future work is discussed. Transmission line reliability Markov system Weather modelling Random environment Common mode failure Kronecker matrix operations MAXIMA
2	Improving the Single Event Effect Response of Triple Modular Redundancy on SRAM FPGAs Through Placement and Routing Cannon, Matthew Joel 01 August 2019 (has links) Triple modular redundancy (TMR) with repair is commonly used to improve the reliability of systems. TMR is often employed for circuits implemented on field programmable gate arrays (FPGAs) to mitigate the radiation effects of single event upsets (SEUs). This has proven to be an effective technique by improving a circuit's sensitive cross-section by up to 100x. However, testing has shown that the improvement offered by TMR is limited by upsets in single configuration bits that cause TMR to fail.This work proposes a variety of mitigation techniques that improve the effectiveness of TMR on FPGAs. These mitigation techniques can alter the circuit's netlist and how the circuit is placed and routed on the FPGA. TMR with repair showed a neutron cross-section improvement of 100x while the best mitigation technique proposed in this work showed an improvement of 700x.This work demonstrates both some causes behind single bit SEU failures for TMR circuits on FPGAs and mitigation techniques to address these failures. In addition to these findings, this work also shows that the majority of radiation failures in these circuits are caused by multiple cell upsets, laying the path for future work to further enhance the effectiveness of TMR on FPGAs. FPGA reliability SEE SEU radiation effects TMR MTTF fault injection radiation testing Markov chain single bit failure single point failure common mode failure common cause failure CAD incremental placement incremental routing Electrical and Computer Engineering Engineering

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On the three-state weather model of transmission line failures.

Improving the Single Event Effect Response of Triple Modular Redundancy on SRAM FPGAs Through Placement and Routing