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61.
62.
Perception of a target voice in the presence of a competing talker, of same or different gender as the target, was investigated in cochlear implant users, in implant-alone and bimodal (acoustic hearing in the non-implanted ear) conditions. Recordings of two male and two female talkers acted as targets and maskers, to investigate whether bimodal benefit increased for different compared to same gender target/maskers due to increased ability to perceive and utilize fundamental frequency and spectral-shape differences. In both listening conditions participants showed benefit of target/masker gender difference. There was an overall bimodal benefit, which was independent of target/masker gender difference. 相似文献
63.
Hanson D.L. Cuneo M.E. McKay P.F. Coats R.S. Rosenthal S.E. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1991,19(5):831-839
Initial experiments to investigate coupling of the four-stage HELIA linear-induction accelerator to a uniformly insulated applied-B ion diode in planar extraction geometry are reported. Results describing the efficient operation of an applied-B extraction ion diode coupled to the HELIA linear induction accelerator operated in positive polarity are reported. Operation of a close-coupled, undermatched, applied-B diode on HELIA was consistent with magnetically insulated transmission line (MITL) electron flow intermediate between locally emitted flow and generalized flow, rather than with full-gap flow. Peak ion coupling efficiencies of 60-70% and peak ion power levels of 0.3-0.4 TW have been achieved 相似文献
64.
The Ramsey number R(3, 8) can be defined as the least number n such that every graph on n vertices contains either a triangle or an independent set of size 8. With the help of a substantial amount of computation, we prove that R(3, 8)=28. 相似文献
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We present the numbers of isotopy classes and main classes of Latin squares, and the numbers of isomorphism classes of quasigroups and loops, up to order 10. The best previous results were for Latin squares of order 8 (Kolesova, Lam, and Thiel, 28 ), quasigroups of order 6 (Bower, 7 ), and loops of order 7 (Brant and Mullen, 8 ). The loops of order 8 have been independently found by “QSCGZ” and Guérin (unpublished, 25 ). We also report on the most extensive search so far for a triple of mutually orthogonal Latin squares (MOLS) of order 10. Our computations show that any such triple must have only squares with trivial symmetry groups. © 2006 Wiley Periodicals, Inc. J Combin Designs 相似文献
67.
Conditions are found under which the expected number of automorphisms of a large random labelled graph with a given degree
sequence is close to 1. These conditions involve the probability that such a graph has a given subgraph. One implication is
that the probability that a random unlabelledk-regular simple graph onn vertices has only the trivial group of automorphisms is asymptotic to 1 asn → ∞ with 3≦k=O(n
1/2−c). In combination with previously known results, this produces an asymptotic formula for the number of unlabelledk-regular simple graphs onn vertices, as well as various asymptotic results on the probable connectivity and girth of such graphs. Corresponding results
for graphs with more arbitrary degree sequences are obtained. The main results apply equally well to graphs in which multiple
edges and loops are permitted, and also to bicoloured graphs.
Research of the second author supported by U. S. National Science Foundation Grant MCS-8101555, and by the Australian Department
of Science and Technology under the Queen Elizabeth II Fellowships Scheme. Current address: Mathematics Department, University
of Auckland, Auckland, New Zealand. 相似文献
68.
We determine the asymptotic number of labelled graphs with a given degree sequence for the case where the maximum degree iso(|E(G)|1/3). The previously best enumeration, by the first author, required maximum degreeo(|E(G)|1/4). In particular, ifk=o(n 1/2), the number of regular graphs of degreek and ordern is asymptotically $$\frac{{(nk)!}}{{(nk/2)!2^{nk/2} (k!)^n }}\exp \left( { - \frac{{k^2 - 1}}{4} - \frac{{k^3 }}{{12n}} + 0\left( {k^2 /n} \right)} \right).$$ Under slightly stronger conditions, we also determine the asymptotic number of unlabelled graphs with a given degree sequence. The method used is a switching argument recently used by us to uniformly generate random graphs with given degree sequences. 相似文献
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