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41.
Compared a new set of queen's norms (for responses to 100 words from the kent-rosanoff word association test) collected in kingston, canada with minnesota norms reported by D. S. Palermo and J. J. Jenkins (see pa, vol. 39:17) for the 1st 9 primaries plus a 10th category for all other responses. Out of the 20 words compared, 19 were significantly different. In the light of previous evidence, word associations seem to have both a time and a place specificity, but its degree does not appear to be attributable to environmental-cultural differences between canada and the united states. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Free-Sets: A Condensed Representation of Boolean Data for the Approximation of Frequency Queries 总被引:5,自引:4,他引:1
Jean-François Boulicaut Artur Bykowski Christophe Rigotti 《Data mining and knowledge discovery》2003,7(1):5-22
Given a large collection of transactions containing items, a basic common data mining problem is to extract the so-called frequent itemsets (i.e., sets of items appearing in at least a given number of transactions). In this paper, we propose a structure called free-sets, from which we can approximate any itemset support (i.e., the number of transactions containing the itemset) and we formalize this notion in the framework of -adequate representations (H. Mannila and H. Toivonen, 1996. In Proc. of the Second International Conference on Knowledge Discovery and Data Mining (KDD'96), pp. 189–194). We show that frequent free-sets can be efficiently extracted using pruning strategies developed for frequent itemset discovery, and that they can be used to approximate the support of any frequent itemset. Experiments on real dense data sets show a significant reduction of the size of the output when compared with standard frequent itemset extraction. Furthermore, the experiments show that the extraction of frequent free-sets is still possible when the extraction of frequent itemsets becomes intractable, and that the supports of the frequent free-sets can be used to approximate very closely the supports of the frequent itemsets. Finally, we consider the effect of this approximation on association rules (a popular kind of patterns that can be derived from frequent itemsets) and show that the corresponding errors remain very low in practice. 相似文献
43.
Andrzej Trybulec Artur Kornilowicz Adam Naumowicz Krystyna Kuperberg 《Journal of Automated Reasoning》2013,50(2):119-121
The collection of works for this special issue was inspired by the presentations given at the 2011 AMS Special Session on Formal Mathematics for Mathematicians: Developing Large Repositories of Advanced Mathematics. The issue features a collection of articles by practitioners of formalizing proofs who share a deep interest in making computerized mathematics widely available. 相似文献
44.
45.
The market success of a new product critically depends on the marketing strategy that is adopted during the introductory phase of its life cycle. The decision theoretic marketing literature provides useful insights to this problem through the application of new product diffusion models. While most of the diffusion models incorporate only marketing variables such as price or advertising into the adoption rates of the new product, we introduce the issue of financial decision making and argue that the success of a new product not only depends on an optimal marketing mix strategy but also on the financial decisions of a firm. We adopt a simple diffusion model and show that in case with demand uncertainty and limited liability more leverage (a higher debt equity ratio) causes the firm to be more aggressive in the product market, i.e., to reduce the price of the product. Our findings suggest that marketing decisions should not be taken in isolation but should be coordinated with financial variables. 相似文献
46.
Elastohydrodynamic lubrication and finite configuration changes in reciprocating elastomeric seals 总被引:1,自引:0,他引:1
A computational framework has been developed for a fully coupled analysis of elastohydrodynamic lubrication and finite deformations of elastomeric reciprocating seals in hydraulic actuators. The relevant formulation is provided, which consistently treats finite configuration changes of the seal modelled as a hyperelastic (Mooney-Rivlin) solid. The steady-state hydrodynamic lubrication is modelled using the classical Reynolds equation. Coupling of the solid and fluid parts is fully accounted for, including friction due to shear stresses in the lubricant film. Detailed results of finite element simulations are provided for two benchmark problems of O-ring and rectangular rod seals in a wide range of process parameters. 相似文献
47.
Carlos Sousa Nuno Mateus Artur M.S. Silva Ana M. González-Paramás Celestino Santos-Buelga Victor de Freitas 《Food chemistry》2007,102(4):1344-1351
A new pigment, resulting from the reaction between malvidin 3-glucoside and catechin in the presence of vanillin, was detected in a model solution. This newly formed anthocyanin-aryl-flavanol adduct was structurally characterized by 1D and 2D NMR and mass spectrometry, and its chromatic characteristics were studied by UV–Vis techniques. The new pigment was shown to have a wavelength of maximum absorption in the visible region (λmax) of 549 nm, conferring on it a purple colour, and a molar extinction coefficient value (ε) of 12,247 l · mol−1 · cm−1. 相似文献
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49.
Wojciech Polkowski Natalia Sobczak Rafał Nowak Artur Kudyba Grzegorz Bruzda Adelajda Polkowska Marta Homa Patrycja Turalska Merete Tangstad Jafar Safarian Elmira Moosavi-Khoonsari Alejandro Datas 《Journal of Materials Engineering and Performance》2018,27(10):5040-5053
For a successful implementation of newly proposed silicon-based latent heat thermal energy storage systems, proper ceramic materials that could withstand a contact heating with molten silicon at temperatures much higher than its melting point need to be developed. In this regard, a non-wetting behavior and low reactivity are the main criteria determining the applicability of ceramic as a potential crucible material for long-term ultrahigh temperature contact with molten silicon. In this work, the wetting of hexagonal boron nitride (h-BN) by molten silicon was examined for the first time at temperatures up to 1750 °C. For this purpose, the sessile drop technique combined with contact heating procedure under static argon was used. The reactivity in Si/h-BN system under proposed conditions was evaluated by SEM/EDS examinations of the solidified couple. It was demonstrated that increase in temperature improves wetting, and consequently, non-wetting-to-wetting transition takes place at around 1650 °C. The contact angle of 90° ± 5° is maintained at temperatures up to 1750 °C. The results of structural characterization supported by a thermodynamic modeling indicate that the wetting behavior of the Si/h-BN couple during heating to and cooling from ultrahigh temperature of 1750 °C is mainly controlled by the substrate dissolution/reprecipitation mechanism. 相似文献
50.
High concentration of phosphorus is a distinctive feature of myelin. An X‐Ray elemental microanalysis study using freeze‐fracture scanning electron microscopy of rat sciatic nerve
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We have used rat sciatic nerves submitted to freezing and freeze‐fracture to determine the elemental composition of small domains of the peripheral nerve studied at high resolution by scanning electron microscopy. We found that myelin of Schwann cells is unique in its high content in phosphorus (P) that was more than 10 times higher than P measured in any other cells. This high concentration in P makes myelin chemistry suitable of monitoring at the subcellular level using the herein described methodology. Microsc. Res. Tech. 78:537–539, 2015. © 2015 Wiley Periodicals, Inc. 相似文献