SEMI

The digital humanities community lost a good friend and colleague with the death of Chuck Bush, long-time Treasurer of the Association for Computers and Humanities and an unfailingly warm presence at the annual digital humanities conference which he attended with his wife, Junola. Chuck was trained as a linguist and worked at Brigham Young University as a Senior Research Consultant in the Humanities Technology and Research Support Center, where he often explored his interests in both print and electronic publishing. He was one of the early advocates for Humanities Computing education, as he both administered and taught in the Computers and the Humanities Program. Humanities faculty at BYU will remember Chuck for his kind and dedicated assistance with arcane computer issues, as well as for his enthusiasm and unfailingly pleasant manner. Chuck served for more than 20 years on the ACH Executive Council, and for those of us who worked closely with him during that time he was a constant source of calm good sense, humor, and organizational memory. An absolutely trustworthy steward for the ACH during its slowly rising fortunes, Chuck played a crucial role in managing the ACH’s alliance with ADHO in 2005–06 and in helping the organization through a challenging transitional time. He could be counted on to suggest a helpful compromise, clarify a tricky point, or bring a discussion down to earth—he was never rattled or partisan.

In this paper we present an efficient general simulation strategy for computations designed for fully operational BSP machines of n ideal processors, on n-processor dynamic-fault-prone BSP machines. The fault occurrences are fail- stop and fully dynamic, i.e., they are allowed to happen on-line at any point of the computation, subject to the constraint that the total number of faulty processors may never exceed a known fraction. The computational paradigm can be exploited for robust computations over virtual parallel settings with a volatile underlying infrastructure, such as a NETWORK OF WORKSTATIONS(where workstations may be taken out of the virtual parallel machine by their owner). Our simulation strategy is Las Vegas (i.e., it may never fail, due to backtrack- ing operations to robustly stored instances of the computation, in case of locally unrecoverable situations). It adopts an adaptive balancing scheme of the workload among the currently live processors of the BSP machine. Our strategy is efficient in the sense that, compared with an optimal off-line adversarial computation under the same sequence of fault occurrences, it achieves