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81.
The relaxation method is used to calculate mole fractions and temperature profiles in a rectification column where a chemical reaction takes place. The method is general and the non-ideal vapor-liquid equilibria can be easily incorporated. The computer time is very low and the danger of divergence can be alleviated by an appropriate guess of relaxation factor. Calculated problems involving esterification reactions are presented. 相似文献
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Most studies that have investigated the use of coarsely grained scales have indicated that the accuracy of statistics calculated on such scales is not compromised as long as the scales have about 5 or more points. Gregoire and Driver (1987), however, found serious perturbances of the Type I and Type II error rates using a 5-point scale. They carried out three computer simulation experiments in which continuous data were transformed to Likert-scale values. Two of the three experiments are shown to be flawed because the authors incorrectly specified the population mean in their simulation. This article corrects the flaw and demonstrates that the Type I and Type II error rates are not seriously compromised by the use of ordinal-scale data. Furthermore, Gregoire and Driver's results are reinterpreted to show that in most cases, the parametric test of location equality shows a power superiority to the nonparametric tests. Only in their most nonnormal simulation does a nonparametric test show a power superiority. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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EK Lang 《Canadian Metallurgical Quarterly》1997,204(3):63A-65A; discussion 66A
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McHale James P.; Kuersten-Hogan Regina; Lauretti Allison; Rasmussen Jeffrey L. 《Canadian Metallurgical Quarterly》2000,14(2):220
Fifty-two married partners played with their 30-mo-olds in both dyadic (parent–child) and whole family contexts and reported on their own coparenting activities (family integrity-promoting behavior, conflict, disparagement, and reprimand). Coparenting behavior observed in the whole family context was evaluated for antagonism, warmth and cooperation, child–adult centeredness, balance of positive involvement, and management of toddler behavior. Parallel balance and management scores were also formed using dyadic session data. Men's reported family integrity-promoting activities and women's reported conflict and reprimand activities were reliable correlates of family group process in both bivariate and discriminant analyses, with links enduring even after controlling for marital quality. Whole family- and dyad-based estimates of coparenting were altogether unrelated, and reported coparenting was tied only to behavior in family context, not to family measures created from dyad-based data. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The method of determination of the gamma-radiation absorption distribution in microstructures of a biosystem is proposed. The absorption capacity and energy absorption distribution of some biomolecules, mass coefficients and optical density of blood and thyroid gland are calculated. Influence of the pollution of biosystem microstructures (liver, blood, thyroid, gland) by hard elements on the energy absorption distribution is demonstrated. 相似文献