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41.
Deepak Dhar  V. Sasidevan 《Physica A》2011,390(20):3477-3485
We study a variation of the minority game. There are N agents. Each has to choose between one of two alternatives every day, and there is a reward to each member of the smaller group. The agents cannot communicate with each other, but try to guess the choice others will make, based only on the past history of the number of people choosing the two alternatives. We describe a simple probabilistic strategy using which the agents, acting independently, and trying to maximize their individual expected payoff, still achieve a very efficient overall utilization of resources, and the average deviation of the number of happy agents per day from the maximum possible can be made O(N?), for any ?>0. We also show that a single agent does not expect to gain by not following the strategy.  相似文献   
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Distortion product otoacoustic emissions (DPOAE) measured in human newborns are not adult-like. More than a decade of work from various investigators has created a well-developed body of evidence describing these differences but the putative anatomy or physiology has only been partially explained. Recently, Abdala and Keefe [J. Acoust. Soc. Am. 120, 3832-3842 (2006)] have identified outer and middle ear immaturities that at least partially describe the differences observed between newborn and adult input-output functions and suppression tuning curves. DPOAE fine structure characteristics and their maturation have not been examined to any extent in the literature. Fine structure characteristics in two groups of ten newborns and young adults with normal hearing sensitivity are compared here. Consistent with previous reports, the newborns show higher DPOAE levels; greater fine structure depth and wider fine structure spacing is also observed in the newborns. Differences in fine structure morphology are also observed between the two age groups. While some of these findings are attributable to an immature outer and middle ear system in the newborns, it is argued that some observed differences in fine structure characteristics might be due to remnant immaturities in passive motion of the basilar membrane in the newborn cochlea.  相似文献   
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The first one-pot three-component coupling reaction of O,O-diethyl hydrogen phosphorodithioate, aldehydes, and aldimines affording 1,2,4-trisubstituted 1,3-thiazetidines is reported. The product is obtained in moderate to high yields (45-94%) and has excellent diastereoselectivity (90-96%) in favour of the cis isomer. Shorter reaction times, ambient temperature, operational simplicity, and high yields are the salient features of the present procedure.  相似文献   
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Wettability studies are of importance for electronic devices. Various methods are known to convert the hydrophobic substrates to hydrophilic substrates, but the studies on the relative dependence of wettability with varying concentrations of an aqueous system are meager. The wetting of different substrates with varying concentration of 1,4-dioxane in water is investigated and the results of concentration dependence of wetting are presented. The FTIR spectrum shows a blue shift of the OH peak--a feature typical of aqueous-1,4-dioxane systems. Concentration dependence of dielectric permittivity of this system also showed an anomaly.  相似文献   
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Annals of the Institute of Statistical Mathematics - This article studies the problem whether two convex (concave) regression functions modelling the relation between a response and covariate in...  相似文献   
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We study the efficiency of the incomplete enumeration algorithm for linear and branched polymers. There is a qualitative difference in the efficiency in these two cases. The average time to generate an independent sample of configuration of polymer with n monomers varies as n 2 for linear polymers for large n, but as exp(cn α) for branched (undirected and directed) polymers, where 0<α<1. On the binary tree, our numerical studies for n of order 104 gives α = 0.333±0.005. We argue that α =1/3 exactly in this case. An erratum to this article can be found at .  相似文献   
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Ohne Zusammenfassung Uebersetzt von Rudolf K?hler (Leipzig). Verbindlichsten Dank schulden wir Herrn Dr. P. B. Ganguly für seine Hilfe bei der Abfassung dieses Artikels.  相似文献   
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