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61.
We exhibit a general class of interactive decision situations in which all the agents benefit from more information. This class includes as a special case the classical comparison of statistical experiments à la Blackwell. AMS 2000 Subject Classification:Primary 91A35.The work of Bruno Bassan and Marco Scarsini was partially supported by MIUR-COFIN. The authors express their thanks to Sylvain Sorin for enlightening comments.  相似文献   
62.
In a recent work (Int. J. Solids Struct. 37 (2000) 1561) by one of the authors, an extended system for calculating critical points of equilibrium paths in imperfect structures was presented. However, the extremum nature of these points was not analyzed explicitly in that paper. In this note, we will fill in the gap and establish a sufficient condition for determining the buckling strength of imperfect structures.  相似文献   
63.
Goldfarb and Hao (1990) have proposed a pivot rule for the primal network simplex algorithm that will solve a maximum flow problem on ann-vertex,m-arc network in at mostnm pivots and O(n 2 m) time. In this paper we describe how to extend the dynamic tree data structure of Sleator and Tarjan (1983, 1985) to reduce the running time of this algorithm to O(nm logn). This bound is less than a logarithmic factor larger than those of the fastest known algorithms for the problem. Our extension of dynamic trees is interesting in its own right and may well have additional applications.Research partially supported by a Presidential Young Investigator Award from the National Science Foundation, Grant No. CCR-8858097, an IBM Faculty Development Award, and AT&T Bell Laboratories.Research partially supported by the Office of Naval Research, Contract No. N00014-87-K-0467.Research partially supported by the National Science Foundation, Grant No. DCR-8605961, and the Office of Naval Research, Contract No. N00014-87-K-0467.  相似文献   
64.
A class of long-range predictive adaptive fuzzy relational controllers is presented. The plant behavior is described over an extended time horizon by a fuzzy relational model which is identified based on input-output closed-loop observations of the plant variables. In this class of adaptive controllers the control law attempts to minimize a quadratic cost over an extended control horizon. When used with linear models, this approach has revealed a significant potential for overcoming the limitations of one-step ahead schemes, such as the stabilization of non-minimum phase plants. Here, a uniform framework is adopted for implementing both the fuzzy model and the fuzzy controller, namely distributed fuzzy relational structures gaining from their massive parallel processing features and from the learning capabilities typical of the connectivist approaches. Issues such as maintenance during the adaptation process of the meaning of linguistic terms used at both fuzzy systems interfaces are addressed, namely by introducing a new design methodology for on-line fuzzy systems interface adaptation. The examples presented reinforce the claim of the usefulness of this new approach.  相似文献   
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本文给出了关系数据库模式中求解关键字的一个算法。算法很简洁并且对于[1]定义的一大类问题,执行时间是多项式级的。  相似文献   
67.
This text presents an English translation of the significant paper [6] on vortex dynamics published by the outstanding Russian scientist S. A. Chaplygin, which seems to have almost escaped the attention of later investigators in this field. Although it was published more than a century ago, in our opinion it is still interesting and valuable. __________ Originally published in: Trudy otdeleniya fizicheskikh nauk imperatorskogo Moskovskogo obshchestva lyubitelei estestvoznaniya, antropologii i etnografii (Transactions of the Physical Section of Moscow Society of Friends of Natural Sciences, Anthropology and Ethnography), 1903, Vol. 11, No. 2, pp. 11–14. Translated from Russian by S. Ramodanov; edited by D. Blackmore; commented by V. V. Meleshko (Department of Theoretical and Applied Mechanics, Faculty of Machanics and Mathematics, Kiev National Taras Shevchenko University, 01030 Kiev, Ukraine. E-mail: meleshko@univ.kiev.ua) and G.J.F. van Heijst (Fluid Dynamics Laboratory, Faculty of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands. E-mail: g.j.f.v.heijst@tue.nl).  相似文献   
68.
We study the initial growth stages of CdS thin films deposited by an ammonia-free chemical bath deposition process. This ammonia-free process is more environmentally benign because it reduces potential ammonia release to the environment due to its high volatility. Instead of ammonia, sodium citrate was used as the complexing agent. We used atomic force microscopy (AFM), Rutherford backscattering (RBS) and X-ray photoelectron spectroscopy (XPS) to investigate the morphological and chemical modifications at the substrate surface during the first initial stages of the CdS deposition process. Additionally, X-ray diffraction (XRD) and optical transmission spectroscopy measurements were carried out to compliment the study. XPS results show that the first nucleation centers are composed by Cd(OH)2 which agglomerate in patterns of bands, as demonstrated by AFM results. It is also observed that the conversion to CdS (by anionic exchange) of the first nucleus begins before the substrate surface is completely covered by a homogenous film.  相似文献   
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70.
Supramolecular nanotube hosts with precisely controlled inner or outer diameters have been synthesized by self-assembly of unsymmetrical bolaamphiphilic monomers or glucopyranosylamide lipids, respectively. Time-resolved fluorescent measurement using 8-anilinonaphthalene-1-sulfonate (ANS) as a probe revealed that the water confined in a cardanyl-β-D -glucopyranoside lipid nanotube has relatively lower solvent polarity corresponding to that of propanol than bulk water. Extensively developed hydrogen bond networks also characterize the confined water in comparison to the case in bulk water. Encapsulation ability of the glucopyranosylamide lipid nanotube has been examined by filling the lyophilized LNTs with gold or silver nanoparticles, ferritin, or magnetic crystals. Filling the unsymmetrical bolaamphiphile nanotube possessing positively charged inner surfaces with negatively charged polymer beads or ferritin proved to be successful without depending on capillary action. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5137–5152, 2006  相似文献   
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