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991.
Using methods of mathematical statistics (cluster, dispersion, and correlation analyses), the impact strength of three types
of glass containers (bottles and jars) was analyzed. Three temperature regions in which molding results in very different
values of the strength of the articles are revealed. The boundaries of the molding temperature regions are critical regardless
of the type of article molded and are probably only determined by the chemical composition of the glass melt. The preferred
mold temperature range is 480–550°C. The results of the study are interpreted based on an analysis of the features of molding
glass at different temperatures.
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Translated from Steklo i Keramika, No. 2, pp. 3–7, February, 2007. 相似文献
992.
Kuzma-Kichta Yu. A. Ustinov A. K. Kholpanov L. P. 《Theoretical Foundations of Chemical Engineering》2002,36(6):524-530
Interface oscillations during boiling are studied experimentally and theoretically. The output-signal spectra of light and acoustic sensors indicate that the liquid-pressure and interface oscillations are interrelated. A model is suggested for the oscillations of a bubble growing on a heating surface, and the existence of an attractor is deduced for the first time from the solution of model equations. The data obtained enable one to determine the ranges of interface oscillation amplitude and frequency and can be used in the modeling of boiling. 相似文献
993.
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本文叙述过氧化钙的性质,并以实例说明过氧比钙在水产养殖、食品加上、果蔬保鲜。环境保护、农作物栽培、橡胶及化工等奋方面的应用。 相似文献
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999.
Informational Entropy: a Failure Tolerance and Reliability Surrogate for Water Distribution Networks
Tiku T. Tanyimboh 《Water Resources Management》2017,31(10):3189-3204
Evolutionary algorithms are used widely in optimization studies on water distribution networks. The optimization algorithms use simulation models that analyse the networks under various operating conditions. The solution process typically involves cost minimization along with reliability constraints that ensure reasonably satisfactory performance under abnormal operating conditions also. Flow entropy has been employed previously as a surrogate reliability measure. While a body of work exists for a single operating condition under steady state conditions, the effectiveness of flow entropy for systems with multiple operating conditions has received very little attention. This paper describes a multi-objective genetic algorithm that maximizes the flow entropy under multiple operating conditions for any given network. The new methodology proposed is consistent with the maximum entropy formalism that requires active consideration of all the relevant information. Furthermore, an alternative but equivalent flow entropy model that emphasizes the relative uniformity of the nodal demands is described. The flow entropy of water distribution networks under multiple operating conditions is discussed with reference to the joint entropy of multiple probability spaces, which provides the theoretical foundation for the optimization methodology proposed. Besides the rationale, results are included that show that the most robust or failure-tolerant solutions are achieved by maximizing the sum of the entropies. 相似文献
1000.