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81.
Todd Eisworth 《Proceedings of the American Mathematical Society》1999,127(10):3067-3071
Mathias (Happy families, Ann. Math. Logic. 12 (1977), 59-111) proved that, assuming the existence of a Mahlo cardinal, it is consistent that CH holds and every set of reals in is -Ramsey with respect to every selective ultrafilter . In this paper, we show that the large cardinal assumption cannot be weakened.
82.
David J. Kennedy Paul Todd Sam Logan Matthew Becker Klearchos K. Papas Lee R. Moore 《Journal of magnetism and magnetic materials》2007
Quadrupole magnetic flow sorting (QMS) is being adapted from the separation of suspensions of single cells (<15 μm) to the isolation of pancreatic islets (150–350 μm) for transplant. To achieve this goal, the critical QMS components have been modeled and engineered to optimize the separation process. A flow channel has been designed, manufactured, and tested. The quadrupole magnet assembly has been designed and verified by finite element analysis. Pumps have been selected and verified by test. Test data generated from the pumps and flow channel demonstrate that the fabricated channel and peristaltic pumps fulfill the requirements of successful QMS separation. 相似文献
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M. J. Todd 《Journal of Optimization Theory and Applications》1976,20(4):397-416
Lemke's algorithm for the linear complementarity problem fails when a desired pivot is not blocked. A projective transformation overcomes this difficulty. The transformation is performed computationally by adjoining a new row to a schema of the problem and pivoting on the element in this row and the unit constant column. Two new algorithms result; some conditions for their success are discussed.This research was partially supported by National Science Foundation, Grant GK-42092. 相似文献
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The interference between Coulomb excitation and nuclear excitation has been observed for 54, 56Fe, 60Ni, 114Cd, 152Sm, and 192Os by measuring excitation functions of elastic and inelastic deuteron scattering at back angles. The interference is strongly constructive, indicating a predominantly imaginary nuclear form factor. DWBA calculations using the collective model, although predicting constructive interference, are unable to predict the magnitude of the observed effect. 相似文献
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J. A. Todd 《Annali di Matematica Pura ed Applicata》1966,71(1):199-238
Summary The Mathieu group M24 can be represented as a collineation group in space of 11 dimensions over the field of two elements. This paper discusses
the geometry associated with this representation.
In memory of Guido Castelnuovo, in the recurrence of the first centenary of his birth. 相似文献