This paper considers the problem of maximizing the number of task allocations in a distributed multirobot system under strict time constraints, where other optimization objectives need also be considered. It builds upon existing distributed task allocation algorithms, extending them with a novel method for maximizing the number of task assignments. The fundamental idea is that a task assignment to a robot has a high cost if its reassignment to another robot creates a feasible time slot for unallocated tasks. Multiple reassignments among networked robots may be required to create a feasible time slot and an upper limit to this number of reassignments can be adjusted according to performance requirements. A simulated rescue scenario with task deadlines and fuel limits is used to demonstrate the performance of the proposed method compared with existing methods, the consensus-based bundle algorithm and the performance impact (PI) algorithm. Starting from existing (PI-generated) solutions, results show up to a 20% increase in task allocations using the proposed method.

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Citation: TURNER, J., MENG, Q. and SCHAEFER, G., 2015. Increasing allocated tasks with a time minimization algorithm for a search and rescue scenario.

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This article presents newly uncovered archival materials which necessitate a rewriting of the early life of Marie Corelli. The many biographies on her are focussed on rumours surrounding Corelli being illegitimate, her eccentricities, and the exposure of lies she told about her age. The most recent biographies, the latest of which was published in 1999, reformulated what had already been written about her and additionally employed analogue genealogical research methods to investigate Corelli’s parentage. They created an account of Corelli’s life which has been subsumed into twenty-first century scholarship. However, the digitisation of genealogical records, as well as of nineteenth and twentieth-century newspapers, has enabled research which renders the twentieth-century biographers’ findings inaccurate and incomplete. This article uncovers Corelli’s working-class origins; it reveals that she spent a lengthy period in America; it finds the likely location of the convent school she attended; and details that she had a fuller performing career than previously understood. It finds truth in the stories that Corelli told about herself, forcing a re-evaluation of her character and her motivation for the concealment of her early life, paving the way for future study.

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One-of the major efforts of our laboratory is the observation of hydrated whole cell mounts in the electron microscope. Efforts to date have shown superior resolution as compared to the light microscope only in the thin portions of spread cells (Parsons et al., 1972). The thicker portions suffer from severe chromatic aberration which limits contrast and resolution even at 800kV. Thus, an image mode capable of enhancing image contrast and eliminating chromatic aberration is necessary. Furthermore, it is presently unrealistic, for the thick portions of the cell, to rely on increasing the accelerating potential. Since the selection of an image mode is a complex function of the required contrast and resolution, and the specimen under observation, we have limited ourselves to a resolution of 20.0nm as an intermediate goal, and ask what image mode will maximize the contrast.

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