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Let u∈C([0,T1[;Ln(Rn)n) be a maximal solution of the Navier–Stokes equations. We prove that u is C on ]0,T1Rn and there exists a constant ε1>0, which depends only on n, such that if T1 is finite then, for all ω∈S(Rn)n, we have limt→T16u(t)?ω6B?1,∞1.To cite this article: R. May, C. R. Acad. Sci. Paris, Ser. I 336 (2003).  相似文献   
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The blue organic dye, 2,6-dichloroindophenol (DCIP), was immobilized on PEGylated Merrifield resin after a chlorination step followed by a nucleophilic substitution reaction, using microwave-assisted methodology. The final product was a blue pigmented resin that can be reversibly reduced by ascorbic acid and changes color from blue to light yellow. Structural elucidation of this immobilized indicator was confirmed through FTIR and elemental analyses.  相似文献   
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Biorobotic research continually demonstrates that behavior and cognition can be the emergent products of (1) embodied agents that are (2) dynamically embedded within an environment and (3) equipped with simple sensorimotor rules. Thigmotaxis is an orientation response to contact manifested in infant rats by wall following, corner burrowing, and group aggregation. Orientation responses have been long thought to be mediated only by sensory or central processes. Here we show that a random control architecture in a morphologically similar robot embedded in a scaled environment can reproduce thigmotaxic behaviors seen in infant rats. We conclude that (1) and (2) may play a larger role than previously thought in the generation of complex behaviors. © 2006 Wiley Periodicals, Inc. Complexity 12: 53–66, 2006  相似文献   
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A TA Instruments Thermal Analysis System (TG) has been interfaced to the Hewlett Packard 5972 quadrupole mass spectrometer. An OSS-2 variable outlet splitter was plumbed between the TG and the mass spectrometer. This interface allows continuous monitoring of the ion intensities of mass peaksm/e=18 (water) andm/e=44 (carbon dioxide) used to elucidate the TG transitions attributable to residual moisture in freeze-dried biological products. Moisture specifications must be met in order to insure product stability throughout the approved shelf life. TG/MS results are discussed for BCG Vaccine, BCG Live (Intravesical) and U. S. Standard Antihemophilic Factor. Karl Fischer and TG/MS moisture results are compared.  相似文献   
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Bayesian networks model conditional dependencies among the domain variables, and provide a way to deduce their interrelationships as well as a method for the classification of new instances. One of the most challenging problems in using Bayesian networks, in the absence of a domain expert who can dictate the model, is inducing the structure of the network from a large, multivariate data set. We propose a new methodology for the design of the structure of a Bayesian network based on concepts of graph theory and nonlinear integer optimization techniques.  相似文献   
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An important class of problems in philosophy can be formulated as mathematical programming problems in an infinite-dimensional vector space. One such problem is that of probability kinematics: the study of how an individual ought to adjust his degree-of-belief function in response to new information. Much work has recently been done to establish maximum principles for these generalized programming problems (Refs. 3–4). Perhaps, the most general treatment of the problem presented to date is that by Neustadt (Ref. 1). In this paper, the problem of probability kinematics is formulated as a generalized mathematical programming problem and necessary conditions for the optimal revised degree-of-belief function are derived from an abstract maximum principle contained in Neustadt's paper.This work was supported by the National Research Council of Canada.The author is grateful to G. J. Lastman and J. A. Baker of the University of Waterloo for numerous suggestions made for improvement of this paper. The problem of probability kinematics was brought to the author's attention by W. L. Harper of the University of Western Ontario.  相似文献   
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